Advances in Computational Methods in Manufacturing

The characteristics of grains during the micro formingForming process are unpredictable. It reflects in the material behavior, interfacial friction and surface finish due to size effectsSize effect. This paper describes the numerical analysis of size effectsSize effect and frictional effects during the plastic deformation of magnesium AZ80 alloy in the micro extrusionExtrusion process. On the basis of true stress–strain curve, the material model is used for numerical investigation. The results reveal that the flow stress increases with decreasing grain size due to increasing interfacial friction. The results are then validated with the micro extrusionExtrusion experiments conducted. Further, the friction generation and load prediction can be achieved through numerical simulation is the primary criteria.

The goal of better fuel economy can be fulfilled by the use of technology like TWBs (Tailor Welded BlanksTailor Welded Blanks). TWB is a product of joining two or more than two materials before any forming operation. The limitations associated with TWBs are the weld line movement and reduced formability. The formability reduction of TWB is due to the thin/weak material involved in it and therefore the tensile study of the TWBs becomes an important aspect. In the present study, investigation of tensile testingTensile testing of Similar Material Dissimilar Gauge TWB and Dissimilar Material Similar Gauge TWB has been done numerically. For the simulationSimulation purpose, ABAQUS/ExplicitABAQUS/Explicit has been used. The results indicate that the thin/weak material governs the strength of the TWB because the failure or necking is observed in that particular side only. Also, it has been observed that the failure locations are found to be at the boundary of thin/weak base material and weld zone.

The current effort is intended to evaluate the forming behavior of the EN-10149-2 (S700mc) steel of 2.42 mm thickness under in-plane plane-stretching (IPPSIPPS) condition at ambient conditions. EN-10149-2 (S700mc) steel has good mechanical propertiesMechanical properties and lightweight that increase the application in automotive, aerospace, and industrial structural design compared to other metals. For which, the tensile and plain stretching test samples were prepared in three rolling directions 0°, 45°, and 90°. The mechanical propertiesMechanical properties such as the yield strength, tensile strength, uniform elongation, total elongation, hardening exponent (n-value), material strength coefficient (K) and plastic strain ratio (R-value) of EN-10149-2 (S700mc) steel are evaluated from the tensile testing. The microstructure and hardness of the material were also evaluated. IPPSIPPS evaluation test has been carried out by stamping circular grids at the middle of the specimen by which measured the manor and major strain using thickness gradient necking criterion (TGNCTGNC). The obtained results from experiments found that the maximum limit strain is appeared for the rolling direction of 45° and followed by 90° and 0°. This indicates that the maximum formability is in 45° rolling direction during the IPPSIPPS test.

Sheet metal forming is a process widely used in the manufacturing industry. There are several sheet metals forming processes are existing including stretch forming process. In the present work, stretch formabilityFormability of AA6023-T6 sheet of 2 mm thickness at room temperature and annealed sheet at 400 °C has been performed. For which mechanical propertiesMechanical properties were evaluated through tensile test for all the conditions. For stretching operations, simulations were performed using limit dome heightLimit dome height (LDH) test using PAM STAMP 2G software. During LDH test, the maximum value of LDH for annealed sheets of AA6023-T6 at 400 °C and minimum value for sheets at room temperature is observed. Uniform thickness distribution for annealed blanks at 400 °C is observed compared to room temperature. The room temperature stretch formabilityFormability of AA6023-T6 alloy sheet has 39.5 maximum dome height and annealed sheet at 400 °C has 43 maximum dome heights. By which, annealed AA6023-T6 sheet has good stretch formabilityFormability compared to room temperature stretch formabilityFormability.

Fuel economy along with cost reduction is the ultimate target of the automobile industries and in order to achieve that, reduction in weight of the automobile body parts should be done. The homogeneous blanks are replaced by Tailor Welded BlanksTailor Welded Blanks (TWBs) while manufacturing the components of an automobile vehicle in order to reduce the weight and cost of the components. TWB is the outcome of joining two or more than two materials having different properties. Despite of having extremely important advantages, technology of TWB is associated with the limitation of weld line shiftweld line shift and formabilityformability reduction during the forming process. During the conventional forming process, formabilityformability of the TWBs is found to be decreasing and weld line shiftweld line shift is observed to be on higher side. In order to improve the formabilityformability of homogeneous blanks, Single point incremental forming process (SPIF) is found to be the excellent solution. However, the combination of SPIF and TWBs technology is not much explored by the researchers. In this present work, simulation of SPIF process for TWBs has been attempted. Effect of different tool initial position on the responses like weld line shiftweld line shift, Plastic Equivalent strain (PEEQ) is investigated. It has been found that the tool dragging effect and deformation of weak material is responsible for the weld line shiftweld line shift during the SPIF process. Particularly for SPIF process, nature and magnitude of weld line shiftweld line shift is affected by the tool initial position.

Concentric tubes are used in heat exchangers, chemical and bioreactors, air conditioners, etc. for transmitting fluid from one location to another. Butt joining of tubes is generally performed and this is accomplished by welding and mechanical fastening. The joining of concentric tubes is mostly performed by fusion welding processes. In the present work, an alternative approach to join two concentric tubes using end formingEnd forming is proposed. A die groove is designed using finite element (FE)Finite element simulation analyses to optimize the process parameters for successful joining. FE code ABAQUS/CAE is used for the FE simulations. The tubes are joined by end forming within the die groove. Such FE simulations helped in practical demonstration of the joining process as well.

SpringbackSpringback is a crucial factor that influences the feature of sheet metal in the sheet metal forming (SMF). In SMF operations, springbackSpringback of the component during unloading mostly determines whether the component confirms to the design dimensions and tolerances. The aim of the current work is to analyze the importance of forming parameters on the responses: punch force and springbackSpringback in U-BendingU-bending of SS 304. Strip length, punch speed and lubricant with three levels each have been considered in the current work as the forming parameters. The effects of different process parameters on U-bendingU-bending of sheet metal have been investigated by conducting experiments on SS 304. Experiments have been conducted as per TaguchiTaguchi’s L9 orthogonal array. The optimum conditions have been determined based on their effect on punch force and springbackSpringback of the sheet metal.

JIS 3302 grade steelJIS 3302 grade steel sheet material has a wide range of applications in automotive industries. Any kind of sheet metal has to undergo different forming test before a real-time application. There are many forming processes are existed to check the formability of sheet materials. Among all the forming process, bending process is one of the formability tests had a drawback interms of springbackSpringback. The springbackSpringback behavior is a measurable quantity for any material after the test. Based on the springbackSpringback nature of sheet material end product shape finalization will be done. This has a dictum for the present work on springbackSpringback effect analysis of JIS 3302 steel sheet material is focused. And also, the effect of various heat treatmentHeat treatments on springbackSpringback characteristics of JIS 3302 steel sheet metal studied using experimental and numerical analysis. For the experimental work, sheet was cut with the dimensions of specimen 150 mm × 40 mm × 2 mm in three different rolling directions such as 0°, 45°, and 90° and bending test conducted on V-bendingV-bending die with 90°. For the tensile testing specimens were cut as per ASTM standard in three rolling directions. The results showed that before heat treatmentHeat treatment, the workpiece has taken more load for bending and recorded higher value of springbackSpringback, whereas, the annealed workpiece has the lowest load consumption to bend and lower springbackSpringback value.

Deep cold rollingDeep cold rolling is a mechanical method of surface treatment used to adapt the desired surface properties in machine components for aerospace industries. In this process, localized plastic deformation is rendered on the surface by rolling a form tool wheel on the specimen to condense high dislocation density which imparts high compressive residual stresses resulting in increased tensile and fatigue strength. The main focus of the present study is to characterize the distribution of residual stresses on the surface and subsurface of an 8-mm-thick plate made of an aluminium alloy AA6061AA6061-O, after deep cold rollingDeep cold rolling operation to different depths of 0.5, 1, 1.5 and 2.0 mm. The observed residual stresses are correlated with the microstructural features in the deformed depths of the specimens. The residual stressResidual stress and grain size in the deformed specimens are examined by using grazing incidence X-ray diffraction and electron backscatter diffraction technique, respectively. It is observed that deep cold rolling leads to significant grain refinement, resulting in high values of residual stresses through thickness. The compressive residual stresses are found to be higher on the surface of the specimen and reduce gradually with the penetration depth. The experimental results are compared with the results obtained by FE analysis using ABAQUS. A good agreement is observed between the experimental and the simulated values of residual stresses and the trends of stress distribution pattern.

Understanding deformation behavior and workabilityWorkability is key prerequisite to optimize process parameters to improve the material processing conditions and confirming safe performance during forming. The deformation characteristics of Inconel 718 and 625 alloys have been investigated using hot tensile tests at temperature range (room temperature to 973 K) at interval of 100 K and at quasi-static strain rate of 0.0001, 0.001, and 0.01 s−1. The experimental findings confirmed that tensile flow stresses are considerably subtle to strain deformation temperature and strain rate. From tensile flow stress behavior, processing mapsProcessing maps have been developed using dynamic material model approach at different value of strains. It was observed that the temperature range (T < 550 K) for Inconel 718 and 600–900 K for Inconel 625 for lower strain rate (0.0001 s−1) efficiency were maximum at different considered strain values. The optimum working parameters for both the alloys have been identified.

Electron beam weld quality is evaluated by careful selection of weld parameters and by control of the temporal distribution of electron beam on surface of work piece. Moreover, the integral effect of the electron beam current and weld velocity on weld joint is significant during electron beam weldingElectron beam welding (EBW) process. In the present work, bead-on-plate EBW of Ti6Al4V alloy plates of 5 mm thickness is carried out to examine the influences of various process parameters with respect to microstructure evolution and weld bead shapes and dimensions. Also, a relationship among input thermal energy, macro- and microstructural characteristics of electron beam Ti6Al4V alloy weldments is established. The experiments were carried out with beam current ranging from 15 to 30 mA and welding velocity from 1200 to 1400 mm min−1. Moreover, a constant focus current and accelerating voltage of 2030 mA and 60 kV are considered. Furthermore, welding modes such as melt-in and keyhole modes are examined with respect to the linear energy and welding process efficiency along with microstructure evolution. In addition, the magnitude of temperature in the heat-affected zone of electron beam welded Ti6Al4V alloy samples is determined using Rosenthal’s analytical model at distinct weld regimes. Furthermore, Marangoni and Fourier numbersFourier number are employed to investigate weld pool characteristics at distinct weld regimes. Based upon the results, it is observed that electron beam power has a significant influence on weldment profile and penetration level while the welding speed has a noteworthy impact on the solidified structure of fusion zone. Also, three weld regimes were identified under the specified welding conditions. Keyhole mode welding is achieved for linear energy above 77 J mm−1, and melt-in mode welding is attained when linear energy is below 45 J mm−1. Moreover, transition mode welding is identified when the linear energy is in between 56.57 and 75 J mm−1. Furthermore, the efficiency of welding process was assessed by relating electron beam power with fusion zone area. It was recognised that a higher linear energy promoted a higher process efficiency comparative to a lower linear energy. A lower linear energy promoted a rich domain of acicular $$\alpha^{1}$$ solidified structure in the fusion zone when compared with higher linear energy. Moreover, the integrity of bead-on-plate welds of Ti6Al4V alloy is of sound quality and without any internal weld defects.

Successful joining of aluminium alloys using friction stir weldingFriction stir welding (FSW) opens a new window research in extending this technique to join aluminium matrix composites (AMCs). Current research is focused on optimization of process variables for multiple responses simultaneously. Experiments were performed using tool pin profile, rotational speed (RS) and welding speed (WS) as ideal process variables for multi-objective optimization in FSW of AMCs. Tensile strengthTensile strength, macro-hardnessMacro-hardness and elongationElongation are considered as multi-response behaviour. Grey relational grade for the chosen multiple responses are obtained using grey analysis. Analysis of variance was utilized to understand the influence of process variables on the grey relational grade. Analysis reveals that RS and WS were the most influencing process variables on the output responses. Confirmation experiments were performed at optimized process variables to validate the present study. Predicted values were in good agreement with the experimental results.

Challenges that prevent broad industry adoption for friction stir welding of high-strength materials are (i) premature tool failure, (ii) selection of tool material and design, and (iii) weldability. To address these typical issues, a finite element-based study for laser-assisted friction stir welding process is carried out in ABAQUS, commercially available FE software. Experimentally, it has been shown that for welding of thick plate, laser assistance ahead of the tool is sought to be beneficial. However, the introduction of laser heating adds another complexity in modeling aspects. It is carried out in twofold. Firstly, the laser preheating is modeled to obtain the thermal map on the sample. Next, the regular FSW process is carried out on the already preheated sample. The important findings achieved are improving weld productivity and satisfactory tool life.

In the present paper, two recently developed intelligent swarm optimizationOptimization algorithms were used for optimizationOptimization of input variables in the electron beam weldingElectron beam welding process. The computational intelligence-based optimizationOptimization algorithms used in this study were bonobo optimizerBonobo optimizer (BO) and cricket algorithmCricket algorithm (CA), which are swarm-intelligence-based algorithms developed by mimicking self-organization, co-evolution, and learning of multiple agents in that particular swarm of the population. Bead-on-plate welding of CuCrZr alloy plate was carried out by electron beam. The welding runs were designed according to central composite design, and regression analysis was conducted to establish input–output dependency. Accelerating voltage, beam current, scanning speed, and focusing distance were considered as input variables of the process, whereas bead geometry parameters and microhardness of weld zone were regarded as the responses of the electron beam weldingElectron beam welding process. An optimizationOptimization problem was formulated with an aim to minimize the weldment area without sacrificing the bead penetration and microhardness of the fusion zone. Penalty function approach was also used in this study to optimize the unconstrained problem. Three optimizationOptimization algorithms were used in this study to solve the optimizationOptimization constrained problem designed to optimize the input variables of the process yielding proper responses of the weld region. The performances of proposed approaches were evaluated based on percent deviation from that of the experimental result. Bonobo optimizerBonobo optimizer outperformed cricket algorithmCricket algorithm and genetic algorithm for optimizing the process.

Dissimilar jointsDissimilar joint are characterized by microstructural change and compositional gradient which evolve large variation in physical and mechanical properties across the welded joints. The combination of dissimilar material is challenging goal for development of parts with locally optimized parameter especially for Ti-SS joints. Due to high cost (like Ti-alloy), joining of dissimilar material (Ti-SS) helps to reduce the cost incurred by eliminating the otherwise unavoidable usage of costly and rare metal. The present study includes the pulsed laser weldingLaser welding of dissimilar jointDissimilar joint of Ti-alloy and AISI 304. EDX analysisEDX analysis is performed on welded specimen for investigation of morphology attained by different zone. It is reported that fusion zone of dissimilar jointDissimilar joint contains very fine-grained morphology because grains are not allowed to grow more at high heat input for shorter time span (pulsation). EDX analysisEDX analysis conveys the presence of intermetallic compounds which is majorly composed of Fe, Ti, and Cr. Cooling rateCooling rate plays important role to determine microstructural variation. But it is difficult to measure it experimentally, so three-dimensional thermal model has been developed and validated with experimental result. Furthermore, average cooling rateCooling rate is estimated for Ti and SS at different locations across the weld zone. Significant difference in thermo-physical properties like specific heat capacity and conductivity are major parameter due to which large difference has been found in the estimated cooling rateCooling rate between Ti-alloy and stainless steel alloy at same location at same instant of time.

Tungsten inert gas (TIG) welding is the most common manufacturing process used to join materials like stainless steel, titanium and aluminium alloys due to their high-quality and inexpensive welds. Furthermore, the difficulty in welding plates having a thickness of 4 mm or more is overcome by employing activated TIG (A-TIG) welding process which uses an activating flux for high depth of penetration in a single pass. Uni-axial tensile testTensile test is conducted to assess the tensile strength of the material by experimentation. In this study, a uni-axial tensile test of base metal (BM) and weld metal (WM) samples are simulated using ABAQUS to evaluate the accuracy of finite elementFinite element modelling (FE) simulation results with the experimental results for predicting the tensile strength. The results show that the stress–strain values predicted by the FE analysis agree with experimental results. Also, the fracture behaviour of experimentation and FE simulation is identical with ductile mode of fracture. The fracture location of the sample in FE analysis is found very similar to experimental fractured samples. The results of ferrite measurement indicate that concentration of delta-ferrite in the WM (5.9 FN) is higher than BM (1.2 FN) content and show better mechanical behaviour in the A-TIG weldments. Also, scanning electron microscope (SEM) shows that the failure of BM and WM resembled to ductile mode-type fracture.

This paper presents a research work on optimization of input process parameters using response surface methodology (RSM) along with grey relational analysis to enhance the weldment quality responses in tungsten inert gas welding of 316L austenitic stainless steel316L austenitic stainless steels. The process control parameters selected for the investigation are welding current, welding speed, and gas flow rate. The experiments have been performed using Box–Behnken design of RSM with three factors, three levels each. Experiments have been performed and output responses: ultimate tensile strength (UTS) and weld width (WW) have also been measured. Grey relational analysis technique has been applied on experimental data to convert multi-output problem into single-response problem. Mathematical model has been developed correlating the process parameters with grey relational grade. The effects of welding input parameters on multi-performance characteristics have been studied graphical contour plots which made from the developed mathematical model. Optimal process parametric has been obtained at higher grey relational grade value. The results of ANOVA and contour plots indicating that output responses, UTS and WW, are significantly influenced by welding input parameters. The concluding remarks have been drawn from the study.

In choosing the right welding processWelding process for an application like welded tube manufacturing, the manufacturing engineers have to take into account a large number of selection criteria. Choosing the right welding processWelding process for any application is difficult not only due to multiple factors affecting the decision but also due to a number of emerging new welding techniques becoming available as alternatives. Some of the alternative welding processWelding processes for manufacturing tubes have been Fretz-Moon process (FM), low-frequency (LF) as well as high-frequency (HF) alternating current resistance welding, direct current (DC)-based resistance welding in addition to gas metal arc welding (GMAW), and submerged arc welding (SAW) in some specific applications. A systematic examination of the decision situation may lead us to an appropriate choice rather than basing the decision on one factor or the other in stand-alone manner. This paper presents an analytic hierarchy process (AHPAHP)- based decision analysisDecision analysis for the selection of welding processWelding process in a case of manufacturing small diameter steel tubesSteel tubes.

In this work, the welding investigation of AISI 201-grade stainless steelAISI 201-grade stainless steel (120 mm × 60 mm with 4 mm thickness) using gas metal arc welding (GMAWGMAW) has been carried out. Four weld parameters, viz. wire feed rate, welding voltage, nozzle-to-plate distance and welding speed, are used to investigate different weld beadWeld bead characteristics [i.e. penetration (P), bead width (W) and bead height (H)]. The welding experiments are performed using Taguchi L9 experimental design, and each run is completed in a single pass. The predictive models are developed to predict weld beadWeld bead geometry, and the performance of the model is validated. The increase in wire feed rate and voltage increases penetration and bead width, while an increase in nozzle-to-plate distance decreases the value of penetration and bead width. The welding parameters are optimized using genetic algorithmGenetic algorithm to determine the optimal combinations of welding parameters for better quality of component having maximum P with minimum W and H at which the maximum weld quality be achieved.

In the present research work, an attempt is made to successfully weld Inconel 718Inconel 718, a nickel-based superalloy with SS 316LSS 316L, an austenitic stainless steel in autogenous mode by using constant current micro-plasma welding process. A finite elementFinite element model method (FEM)-based, three-dimensional (3D) thermal model is developed for butt welding configuration between the selected bimetallic combinations by using a double-ellipsoidal volumetric heat source model. A good consistency is found between the numerically obtained and experimentally obtained weld bead measurements. The numerical model is further used to extract peak temperatures, time–temperature profiles along with average cooling rates of the welding processes. Obtained cooling rates are correlated with the weld micro-structures and mechanical properties. Micro-structural study by SEM analysis has shown coarse columnar dendritic structure in the weld interior for the higher heat input welding case, whereas lower heat input during welding leads to fine weld micro-structure due to high cooling rate. An improvement in the tensile strength and hardness value is observed with increase in weld cooling rate and low heat input during the joining process.

Localized heating and cooling during welding introduces residual stress in the weld joints due to the thermal gradients. The microstructure formation in 2.25Cr–1Mo steel2.25Cr–1Mo steel is very much sensitive to the rate of cooling and eventually, the austenite may transform to pearlite/bainite/martensite. A variant of Tungsten Inert Gas (TIG) welding called Activated-TIG (A-TIG) welding was made use of in this study. Here, we have tried to develop a numerical model based on the finite element method to predict the thermo-mechanical behavior of 6 mm thick 2.25Cr–1Mo steel2.25Cr–1Mo steel weld joints, with accounting solid-state phase transformation. The heat energy supplied to the workpiece is determined and calibrated in the heat source model. Simulated thermal cycle showed a peak temperature of 1377 °C at 8 mm distance away from the weld centerline, whereas, the experimental result showed 1371 °C. A k-type thermocouple was used to measure the temperature distribution during welding. The simulated thermal distributions were sequentially coupled to mechanical analysis. The evolution of stress and ultimately the locked-in residual stresses were determined. X-ray diffraction studies showed the peak residual stress near heat affected zone of 592 MPa and the vertical height gauge was used to measure the distortion before and after welding. The predicted residual stresses and distortion showed good agreement with the experimental measurements.

In the present study, thermomechanical analysis of autogenous hybrid laser-TIG welding of type 316L(N) austenitic stainless steelStainless steel has been carried out. It has been realized that the residual stress due to welding plays a vital role in the mechanical properties of the joint and its performance during service. Therefore, it is important to study the residual stress of type 316L(N) stainless steelStainless steel weld joint produced by hybrid weldingHybrid welding process. First, the thermal analysis was carried using a hybrid heat source consisting of conical and double ellipsoidal models. The heat source was calibrated by comparing the simulated weld bead profile with that of the experimentally obtained weld bead profile. Then, the obtained temperature distribution was sequentially coupled to the mechanical analysis. The simulated thermal cycle was validated by temperature measurements using noncontact real-time IR thermography. The simulated residual profile was validated by an ultrasonic technique employing critically refracted longitudinal waves. The ferrite content of the weld metal was measured using ferrite scope. Distortion in the weld joint is measured using digital vertical height gauge. Optical microscopy is employed for microstructural characterization of the weld joint. The weld metal exhibited a peak tensile residual stress value of 320 MPa. The predicted distortion values were very low. There was a good agreement found between the predicted and experimentally measured thermal cycles, residual stresses, and distortion.

Electromagnetic crimping (EMC)Electromagnetic crimping (EMC) is one of the advanced manufacturing technologies used to join lightweight material including metals with metallurgical and thermal property differences. This paper investigates EMC process numerically to deform aluminum tube (Al6061-T6) to the steel profiled rod using the electromagnetic (EM) module of LS-DYNATMLS-DYNATM. Electromagnetic crimping methods can join multiple material systems without melting. A longitudinal groove was designed on steel rod for mechanical interlocking to resist the torsional load. Groove geometrical parametersGroove geometrical parameters like groove length, depth, edge radius, and width were kept constant. Effects of voltage on an effective plastic strain, resultant impact velocity, resultant displacement, and temperature were studied in detail. Moreover, the simulation was carried out also to analyze the effect of capacitance on process parameters, and results are discussed in detail. The developed model is validated and found in a good agreement with experiment. Based on the results found, it is possible to predict essential process parameters for enhanced joint strength.

Nowadays, the automobile industries are more concerned about reducing automobile weight for improving fuel efficiency and reduced vehicle emission. Hence, there is a need for relatively lighter weight materials like aluminium alloy replacing steel parts for automobiles. However, joining of these lightweight materials is very difficult using conventional spot welding technique, which is a slow process also. In the present study, an alternative high-speed advanced mechanical fastening technique, namely self-pierce rivetingSelf-pierce riveting is used for joining of these lightweight sheets of different materials. In this process, a semi-tubular rivet is pressed by a punch into two or more sheets which are supported on a die. Due to the special design of die shape, the rivet flares inside bottom sheet to form a mechanical interlock. Experimental measurement of temperatureTemperature inside the sheets during the process is a difficult task, as the process takes place for a fraction of a second within a span of 10 mm. In the present study, the temperature rise during SPR process is predicted by finite element simulationFinite element simulation using Abaqus® for any combination of sheet materials, process conditions and tool dimensions to understand the process. In addition, an ANN model is developed to predict the temperature rise during joint formation in sheets for any combination of process parameters. The ANN model accurately predicted the temperatureTemperature evolution during the process. Hence, with the hybrid ANN-FEM strategy one can design and optimize the process, tool and material conditions, efficiently, which otherwise will be time and resource-intensive.

In the present work, AISI 52100 steel hard turning has been performed using PCBN tools. Cutting speed, feed, depth of cut, nose radius and negative rake angle are the input parameters, and the measured responses are surface roughness and workpiece surface temperature. Experiments are planned as per central composite rotatable design (CCD) of response surface methodology (RSM). The effect of input parameters and their interactions are discussed with main effects plot and response surface plots. Further, the multi-objective optimizationOptimization scheme is proposed by adopting grey relational analysis (GRA) coupled with the principal component analysis (PCA). Results demonstrated that responses considerably affected by speed followed by nose radius, feed, depth of cut and negative rake angle. Cutting speed 1000 rpm, feed 0.04 mm/rev, depth of cut 0.4 mm, nose radius 1 mm and negative rake angle 15° are the obtained optimum cutting parameters.

The cutting-edge radiusCutting-edge radius of the tool has significant effects on the machiningMachining process, as it influences the cutting forces, stresses, and temperature at the tool–chip interface. These parameters ultimately affect the tool life and surface integrity of the finished workpiece. The presence of cutting-edge radiusCutting-edge radius in the tools protects them from easily chipping off during the cutting process. A finite element based ABAQUS™ model is used to evaluate the effect of cutting-edge radiusCutting-edge radius for 20, 40, and 60 μm on the cutting forces for orthogonal cutting of Ti6Al4VTi6Al4V alloy at different cutting parameters. It was observed that the cutting-edge radiusCutting-edge radius influences both the cutting and thrust forces. An increase of 4–8% and 12–14% in the cutting force and thrust force was observed when the cutting-edge radiusCutting-edge radius changes from 20 to 60 μm. The temperature in the tool was increased with increasing cutting-edge radiusCutting-edge radius.

In recent decades, the noticeable amount of research has been carried out in the role of non-metallic inclusionsNon-metallic inclusions and their relationship to the machinabilityMachinability of various steels. This paper compares the performances of EN alloy steels for varied machinabilityMachinability aspects throughout the machining under dry cutting condition. Cutting speed, feed, and depth of cut were the major ruling parameters affecting the machinabilityMachinability of materials. The present works review the machining of different alloy steels and the role of non-metallic inclusionsNon-metallic inclusions in them. More precisely, the effects of composition and morphology of inclusions on machinabilityMachinability factors such as cutting force and chip size and shape are discussed and summarized. EN 1A Pb&Te alloy steelAlloy steel provides lower cutting force, and good curl or breakdown chips thus provides the better machinabilityMachinability.

This paper determines the optimum process parametersProcess parameter of the non-conventional electrical discharge machining. The performance of the EDMEDM machine depends upon the process parameter used. In this analysis, weight percentage, pulse current (Ip), discharge voltage (V), and pulse duration (Ton) are used as process parameters. The optimized output parameters are MRR, TWR, surface roughness, and radial overcut. By using face-centered composite design, nine trials were conducted on the workpiece which is made up of Al7075/SiC/WS2 hybrid composite. The trial results obtained were used in decision-making method correlation coefficient and standard deviation (CCSD) integrated approach. These results give useful information on how to control the machining parameters and accuracy of the components produced from EDM. Decision-making method used is simple, and results obtained are confirmed by conducting confirmation experiments.

This paper deals with the measurement of residual stress produced during turning operation. CNC turning is a machining process to remove unwanted material from the workpiece to produce desired rotational parts. Turning is a widely used cutting process in the manufacturing industry, and thus, continuous research is going on to optimize it because of cutting high-performance dynamics, workpiece materials, and cutting tools. Turning operation was performed on H13 tool steel workpiece dimensions 110 × Ø22 mm on CNC Lathe machine tools. H13 tool steel is used for manufacturing of friction stir welding and processing tool. The main aim of the current study is to determine the residual stress using PulsetecµX-360n portable stress analyzer setup, and Abaqus 6.14 software was used to simulate the turning process. Experimental tests were performed on H13 tool steel materials which are in form of FSW/FSP tool, which consists of different pin profiles. The experimental outcomes are then compared with the outcomes obtained from the simulation. Experimental results validate the simulation results for both the tool pin profiles which are lying within the acceptable range.

Molecular dynamicsMolecular dynamics (MD) and single-crystal plasticitycrystal plasticity finite-element method (CP FEM) are approaches used to simulate the micro-machining process. At such small-length scales, anisotropic behaviour of material becomes important; the two methods can essentially capture it. Therefore, it is important to understand the fundamental principle behind these methods as well as their capabilities and limitations in order to select the scheme to simulate the micro-machining process. In this paper, the fundamentals of MD and CP FEM are introduced in brief. The applicability of the respective method is further illustrated with the help of examples from the literature. Thereafter, the two methods are compared and discussed in terms of their various aspects and capabilities. This discussion should enrich the reader and assist their choice of an appropriate simulation method.

The main objective of this work is to study the effect of material hardness, workpiece speed and depth of cut on surface finish and material removal rate in cylindrical grinding process. For three process parameters at three different levels, L9 orthogonal array (OA) is selected. Experiments were conducted, and roughness values and material removal rates are calculated. S/N ratio is performed to get the optimal process parameters for surface roughness and material removal rate. ANOVA is carried out, and the percentage of contribution of each selected parameter was found.

In orthopedic surgeryOrthopedic surgery, sequential drillingSequential drilling is the process of making multiple holes to facilitate the implant fixation. During the bone drilling process, the generated heat will cause thermal damage that affects the implant fixation strength because of “osteonecrosisOsteonecrosis,” a permanent death of the tissues around the drilling site. In this work, an attempt was made to identify the effects of sequential drillingSequential drilling of cadaveric human femur boneFemur bone on the heat accumulation. To perform the sequential drilling process, the rotational speed of 1500 rpm and 80 mm/min feed rate was considered with the 4 mm deep holes. Thermal images were captured using Sonel® infrared thermography during the drilling process. It was identified that the accumulated heat increased as the number of sequential holes increased. It was also observed that the distance between the drilled holes influenced the amount of temperature rise. The number of sequential holes drilled and the distance between the holes greatly influenced the temperature rise. This study showed the accumulation of heat during sequential drillingSequential drilling and its consequences in the temperature rise. It is recommended to the surgeons to increase the field of a drilling site in such a way to increase the distance between the subsequent holes to avoid thermal damage to the bone to prevent from further complications.

A thorough understanding of laser-based additive manufacturing process and effect of various process variables such as scanning velocity and laser beam power on melt-pool dimensionsMelt-pool dimensions and temperature variation is a promising task in design and manufacture of an able product. The present work is focused on comprehending the thermal and melt-pool behavior of a high layer thickness five-layer laser additive manufacturingLaser additive manufacturing of Ti–6Al–4V alloyTi–6Al–4V alloy quantitatively. A three-dimensional (3D) nonlinear transient thermal model is developed based on a finite element procedure to simulate single- and multi-layer of Ti–6Al–4V alloy and to estimate melt-pool dimensionsMelt-pool dimensions and thermal cyclesThermal cycles. In this work, temperature-dependent material properties and Gaussian distributed ‘disk’ heat source model are implemented along with actual process boundary and initial conditions. Also, the influence of laser beam power and laser scanning velocity was examined with respect to melt-pool characteristics and thermal cyclesThermal cycles. The laser scanning velocity ranges from 200 to 500 mm s−1 and laser beam power from 100 to 400 W are examined. It is observed that the temperature rises for successive layers as the laser power supply continues on consecutive layers. Also, it is obvious that with the rise in temperature, melt-pool dimensionsMelt-pool dimensions also increase. Furthermore, the melt-pool dimensionsMelt-pool dimensions increase as the number of deposited layers increases. Time–temperature history and melt-pool evolution in different layers with respect to laser beam power and laser scanning velocity are presented. To verify the effectiveness of the developed model, simulated results are compared with experimentally measured melt-pool profiles and dimensions. A fair agreement between experimental results and computed values is achieved.

The cold gas dynamic spray is a solid powder deposition phenomenon of coating and repairing with a broad materials range. This deposition technology gained attention not only in institutions but also in industrial aspects. This coating technology is a surface engineering technology which is presently replacing electron, laser beam type of technologies for additive manufacturing. This study provides the pattern of deformation of both particle and substrate under the impact of high particle velocity. An ABAQUS/Explicit, a finite element methodology was used to forecast the coating behaviour of different engineering materials. A FEM approach was used for the simulation of the metallic impact of substrate and particle. A wide range of impact velocities was used to finding the threshold or critical velocity for the proper deposition, phenomenon of rebounding and also to divulge the mechanism of governance, i.e. adiabatic shear instability (ASI). This study focused and revealed how engineering materials that are commonly used in aerospace engineering behaved under different impact conditions using kinetic spray coating technology.

Amongst various futuristic manufacturing technologies, additive manufacturingAdditive manufacturing is fast emerging from the lap of laboratory-scale testing to full-scale commercial applications. StereolithographyStereolithography of polymeric materials has the potential to offer cost-effective and accurate solutions for many industrial sectors such as automotive, aerospace and electronics. However, the process of understanding and comprehending the underlying physics of the liquid additive manufacturingAdditive manufacturing process is still in its infantile stage. In the present work, an attempt was made to computationally model the laser beam and the photosensitive resin interaction in the stereolithographyStereolithography process. The laser source was considered as a Gaussian heat source, and the liquid vat was considered as a homogenous isotropic fluid domain. Finite element modellingFinite element modelling approach was utilized to evaluate the thermal changes occurring during the photo-initiated curing process. The resultant process quality indicators such as transient temperature distribution across the liquid vat, conductive and radiative heat flux, laser intensity on the liquid layer and its diminishing impact across the layer thickness were computed and compared. Maximum local temperature as high as 390 K was found on the irradiated location which cools down rapidly due to heat conduction and diffusion. However, the temperature reduces exponentially with the height of resin vat, and it takes around 4 s for the irradiated point to cool down to the ambient temperature and gets cured. Approximately $$1.1 \times 10^{6} \,{\text{W/m}}^{2}$$ of laser intensity is produced on the bottom surface of laser. Some selected results were validated with contemporary literature and found to be satisfactorily consistent.

Manufacturing and designing of various functional components in the fields of engineering, automobile and aerospace are being done by additive manufacturing (AM) technology. These activities must be supported by the knowledge of process parameters that may influence mechanical properties of industrial products. Fused deposition modelling (FDM) is one of the most popular AM technologies in which the quality of part depends on selection of process variables. The present work focuses on two input process parameters, i.e. raster orientation and infill density and its effect on the mechanical properties of 3D-printed samples. The PLA samples were prepared in XY and XZ orientation with infill density of 20, 40, 60, 80 and 100%. The tensile testing is conducted to evaluate the effects of these process parameters on tensile strength, ultimate strength, etc. Further, fractography was performed and it is concluded that dimple size and distribution on fractured surface were affected by the infill density. Printing time was also checked and compared for specimens printed for different parameters, which shows printing time is least for XY orientation and maximum for XZ orientation. Printing time increases as the infill density increases from 20 to 100%.

Pistons are the most important parts of an automobile engine. Pistons are manufactured by various die casting processes like sand casting, gravity die casting, pressure die casting and automatic die casting. Manufacturing assets and processes have different intelligent attributes based on embedded intelligent systems. Not much of work seems to be available for measurement and quantification of machine intelligent quotient (MIQMIQ) for metal casting manufacturing machines. To assess the intelligence of die casting machinesDie Casting Machine, three methods are developed. High MIQMIQ indicates the lower interaction between human and die casting machineDie Casting Machine, i.e., the machine can take comparatively higher percentage of decisions in machine operations. In the present work, an attempt has been made to develop a stepwise procedure for MIQMIQ measurement by three methods, i.e., human–machine cooperative systemHuman Machine Cooperative System, geometric polytope method and multiple perspective analysis methods. MIQ for three die casting machineDie Casting Machines is computed based on human–machine cooperative method, and it has been found that automatic die casting machineDie Casting Machine has the highest MIQ (109.31) followed by pressure die casting machine (59.69) and gravity die casting machine (26.44) the lowest.

Closed-cell ultra-light aluminium foamsAluminium foams are often used as structural materials in aerospace, railways and automobile sectors as they provide good strength to weight ratio with high impact strength and corrosion resistance. Melt -based metal foams can be casted using indirectIndirect processing foaming techniques, wherein gas bubbles are created inside the melt which has been pre-treated in a suitable way. The properties of these metal foams are directly affected by nature of porosityPorosity control, which is difficult to measure and control experimentally. Therefore, theoretical solutions have to be developed to control this porous structure. In the present work, a aluminium foam, prepared using foaming method using blowing agents with porosityPorosity control ~86%, is used, where the effect of melt viscosity and solidification time on gas bubble size and its rising velocity inside melt have been theoretically studied. The calculations showed that rising velocity of hydrogen gas bubbles, aluminium melt viscosity and solidification time are responsible for motion of bubbles in the aluminium melt. Control of this movement of bubbles can result in optimum porosityPorosity control in the solidified foam. A relationship has been established for viscosity enhancement due to the addition of additives like Ca, Al2O3, SiC, TiB2, SiO2, BN and their influence on bubble size and its rising velocity during solidification of this foam. Overall, the study suggested amount of additives that are required to be added in a given volume of aluminium melt, to increase melt viscosity and to maximize bubble entrapment. The results also showed that a cooling time of ~8 s leads to efficient bubble entrapment with uniform pore structure and hence properties of aluminium foam.

This research paper narrates a manually constructed Mamdani based on fuzzy algorithm model for envisaging surface roughnessSurface roughness and linear shrinkageLinear shrinkage of die castingDie casting, so that defects can be refrained from the casting in terms of surface finish and dimensions. A set of rules established by the help of mathematical model have been used to derive two fuzzy controllers which are being used in this process. With the help of this fuzzy algorithm, high production rate and high quality of products can be obtained by controlling process parameters. Confirmation experiments reveal that these fuzzy logicFuzzy logics are able to attain optimum grouping of the process parameters. Hence, the quality of casted products in die castingDie casting process can be improved to a greater extent by this approach. The predicted surface roughnessSurface roughness and linear shrinkageLinear shrinkage by this model had an error of only 3.55 and 6.02%, respectively, which was confirmed by checking the validity of the model developed by performing confirmation experiments. This proposed model can be reasonably utilized by the industries involved in die castingDie casting around the world to increase the overall effectiveness of the process and product.

The process of casting in foundry is complex and involves large process to get the required part, and such process needs simulationSimulation before manufacturing. Casting simulation may save material and gives optimal process of casting in foundry. The defect minimization or prevention is challenging and plays significantly in enhancing the productivity of the foundry. The aim of the present study is to compute hot spots and hot tearing in Al–Cu cast alloy. The originating points of the feed paths represent the hot spots that lead to a shrinkage defect. Some studies have been carried out on hot tearHot tear. It was observed that the location of hot tear is at inter-junction of mold cavity to the gate. The developed model is used as bench mark to predict the location of hot spotHot spot and hot tear of Al–Cu cast alloy by green sand casting method with casting simulationSimulation software.

The fluidityFluidity of molten metal plays a vital role in the casting process when we are confined in manufacturing thinner sections. The aim of the present study is to determine the effect of pouring temperaturePouring temperature on the fluidityFluidity of Al–Cu cast alloyAl–Cu cast alloy. The simulationSimulation was performed by AutoCAST-X software with altered pouring temperaturesPouring temperature of 700, 750, and 800 °C. It was observed that the fluidityFluidity was enhanced when the pouring temperaturePouring temperature at 800 °C for the aforesaid cast alloy. Similarly, it was found that the volume of fill increased with the increasing pouring temperaturePouring temperature and also strong agreement was observed with the solidification time and fill time.

This paper presents the optimization and analysis of machining parameters on machining of Al6061 alloyAl6061 alloy using magnetic field-assisted powder-mixed electrical discharge machining (MFAPM-EDMMFAPM-EDM) process. For performance analysis, peak current (IP), spark on time (SON), spark off time (SOFF), powder concentration (PC), and magnetic field (MF) are considered as machining parameters and tool wear rateTool wear rate (TWR) as performance measures. The experimental design based on Box Behnken Design is used for conducting the experiments and single objective optimization is performed using teaching–learning-based optimization (TLBOTLBO) algorithm. Peak current is observed as the most significant parameters followed by spark on time, magnetic field, and powder concentration. Model to predict TWR is developed in terms of machining parameters. The optimum set of machining parameters for minimum TWR using TLBOTLBO algorithm is obtained at IP-1 A, SON-30 µs, SOFF-51 µs, PC-10 g/l, and MF-0.45 T.

Wire electrode discharge machining (WEDM) is an accurate but an expensive and time-consuming process. In order to establish a stable connection between input and output variables, implementation of soft computing techniques can be useful. Therefore, the current study focuses on comparing adaptive neuro-fuzzy inference system (ANFIS)-based subtractive clustering algorithm with numerous input combinations as well as multivariate regression models in order to simulate and map the output variables with the process parameters used during experimentations, namely pulse-on time (Ton), servo voltage (Sv), wire feed (Wf), and wire tension (Wt). Results show that ANFIS models have the ability to estimate the edge roughness (Er) and kerf width (Kw) more accurately with 96.2 and 97.3% accuracy. ANFIS model is more reliable, accurate, and productive as it uses the learning of neural networks to predict. Also, the developed model has been used to study and explain the effect of various input variables upon the quality of machining. High pulse-on time directly decreases the quality increasing the edge roughness and kerf width which are both undesirable. Low wire feed has shown to decrease both the response parameters regardless of other input parameters. Wire tension has shown much less significant effect as compared to the other three variables.

Today, complex freeform surfaces are widely used on parts in automobile, aerospace, and die– mold industries. Multi-axis computer numerical control (CNC) machines are used to manufacture such parts as they need tighter tolerances and high surface finish to meet functional and aesthetic requirements. Scallop height is primarily used to measure and assess the surface quality of such products. The inspection methods used in practice are expensive and need experienced personnel. No simulation techniques exist, as of now, to estimate the part quality apriori. This paper reports the development of an algorithm to estimate the scallop heights for freeform surface machining from the CNC part programs. The developed system takes STL file of the simulated machined component from the VERICUT and slices it along the specified planes. Points so generated are analyzed to estimate scallop heights at various regions on the surface using numerical curve-fitting techniques. The developed system has been validated with the case studies. The system provides a robust and accurate estimation of the part quality.

This paper investigates the influence of guidesGuides on the critical speeds of circular saws. Guides constrain the out-of-plane lateral motion of these rotating saws and have a stabilizing effect by increasing the critical speeds, below which the rotating saw is stable. We present expanded analytical formulations in which guidesGuides are modelled as multiple discrete spring-damper elements approximating the distributed nature of the guide pad and saw interactions. We observe that for a given guide pad area, convergence analysis is necessary to understand how many discrete spring-damper elements are actually necessary to approximate the distributed nature of the guide pad and saw interactions. Curiously, we observe that damping in the guidesGuides has no significant influence on the critical speed and that it only changes the nature of frequency-speed characteristics of the rotating saw. We also find that critical speeds are sensitive to guidesGuides modelled with a distribution of discrete spring elements along the radial and/or circumferential directions. These observations suggest that more generalized formulations that model the guide pads as distributed spring-damper systems, rather than multiple discrete spring-damper elements, are necessary. We expect our findings to instruct and advise the placement of guidesGuides on rotating circular saws, such that a preferential increase in critical speeds can be obtained to make possible high speed and productivity circular sawing operations in the wood-working and metal-cutting industries concerned with circular sawing processes.

Serrated cuttersSerrated cutters with their complex local tool geometries result in continuously changing chip thicknessChip thickness and engagement conditions due to a change in local radius along the serration height. This change in geometry results in a reduction of cutting forcesCutting forces, and hence these cutters are favoured in the rough cutting of difficult-to-cut materials. The change in local radius of the cutter is also influenced by the radial run-outRun-out on the tool. Run-out, though undesirable, is inevitable. How this run-outRun-out influences the local radius, chip thicknessChip thickness, and forces is not entirely understood for serrated cutters. This paper fills that gap, by presenting a model that factors in the influence of radial run-outRun-out on cutting forces for serrated cuttersSerrated cutters. Investigations with different sets of cutting parameters show that for cutting with a low feed, and high axial and radial depths of cut, the influence of run-outRun-out on the cutting forcesCutting forces is negligible. For the case of cutting with high feeds however, we find that run-outRun-out adversely impacts cutting forces for any combination of axial and radial depths of cut. We also observe that with certain combinations of cutting parameters and run-outs, serrated cutters lose their advantage over regular end mills with similar levels of run-outs. Our findings suggest that serrated cuttersSerrated cutters may be used even with high levels of run-outs when the feed is low, and that their use should be avoided for any level of run-out when cutting with high feed rates.

In the current work, modeling and optimization of input parameters in wirecut electric discharge machine (WCEDM) of titanium [Ti-6A-4V] (Grade 5) were attempted. WCEDM working variables such as pulse-on-time (TON), pulse-off-time (TOFF), servo-voltage (SV), peak-current (IP), and wire feed were considered to study the responses of cutting speed or speed of cut (CS) and wire wear ratio (WWR). Each input parameter was set at three levels. Experiments were conducted as per central composite face (CCF)-centered design. Based upon the runs’ data, model equations for CS and WWR were developed using multiple linear regression. Optimization of practice parameters had been performed with the help of level mean analysis, response graphs, and model equations. From the analysis, it was observed that pulse-on-time was the substantial considerable input variable followed by servo-voltage, peak-current, and pulse-off-time.

Use of microwave energy at 2.45 GHz for micromachining offers promising nontraditional machining technique for brittle materials like glassGlass. However, process is yet to be analyzed for better understanding of the process mechanism to minimize the defects associated with the thermal damages in the machined materials. In the present paper, the process was studied using the finite element method, and a 3D model of the microwave drillingMicrowave drilling setup was developed using COMSOL Multiphysics v5.2 software. Simulation was carried out to study the thermal characteristics of the materials with time while irradiated during the process. The main affecting parameters were analyzed to find out the possible reasons for the defect associated with this process. Simulation of the microwave drilling process was carried out for a combination of graphite concentrator (diameter = 500 µm) and borosilicate glass (thickness = 1.2 mm) at 700 W. Simulation results revealed that the electric fieldElectric field intensity near the concentrator tip was higher (approximately $$8.99 \times 10^{6} \,{\text{V}}/{\text{m}}$$ ) enough to ionize the air dielectric media which causes the generation of plasma around the tip of concentrator. The maximum temperature in the machining zone was observed approximately 1100 °C in 6 s. The rapid rise in temperature in the specimen induces a very high thermal stressStress (approximately 85 MPa) which reaches beyond the fracture strength of the borosilicate glass. The experimental investigation of the same concentrator-specimen combination demonstrated the similar pattern of fracture while drilling in the air using the same processing parameters.

The study emphasizes on the effect of polarity change while conducting experiments using tungsten disulphide in powder-suspended micro-EDMMicro-EDM process on Ti6Al4V alloy workpiece with brass tool electrode. For design of experiment, Taguchi method with L9 orthogonal array has been adopted. For each set of experiments, three levels of factors such as voltage, duty factor and machining time are considered. The responses such as MRR (higher the better) and SR (lower the better) are calculated, and a grey fuzzyGrey fuzzy logic model is built for optimization of the parameters. ANOVAANOVA table shows that the voltage plays the most significant role when machining in straight polarity followed by machining time and duty factor, whereas for reverse polarity machining time is the most significant one followed by voltage and duty factor. In case of straight polarity, confirmatory tests were performed at V = 25, DF = 55 and T = 8 and in reverse polarity at V = 25, DF = 45 and T = 8 and GFRG in case of straight polarity was found to increase by 0.216 and increased by 0.182 for the reverse polarity.

This paper presents multi-output advancement for microplasma arc welding (MPAWMPAW) process using utility methodology. It is an advanced unconventional welding process in which very thin (usually less than 1 mm) metal surfaces are joined using plasma arc. A successful trial has been made to weld 0.5-mm-thick 316L stainless steel sheet. An attempt has been made to optimize the MPAWMPAW parameters for a desired equal-weighted multi-output such as ultimate tensile strength, yield strength, percentage elongation, Young’s modulus, and weld hardness at fusion zone and heat-affected zone. The design of experiments L27 orthogonal matrix was conducted using levels of several visually successful trials. An analytical tool analysis of variance and interaction has been clubbed with utility approach to get desired aim of experimentation. As per different work application, the different preferable weight can be incorporated into the output. The confirmation test correlated with the best-desired aim of the output parameter. It was observed that overall utilityOverall utility for all mechanical properties and corresponding S/N ratio is enhanced with 0.28 and 0.42 values, respectively. It was found that welding speed with 49.01% and pulse time with 13.21% are the most significant parameters. The enhancement in the responses confirmed the approach of the feasibility of utility analysis which can help to enhance the product reliability for an industrial application.

High-aspect-ratio high-quality microholesMicroholes are required in turbine blades to improve cooling performance. These cooling holes are drilled by pulsed laser and hence dimensional as well as geometrical tolerances like circularity and cylindricity are important. The measurement of geometrical features of the microholesMicroholes is a very challenging task without destroying the components. In the present work, the microholesMicroholes are produced on Ti6Al4V alloy by ultra-short pulse laserUltra-short pulse laser. The geometrical features of microholesMicroholes are then captured using a non-destructive technique, namely computed tomographyComputed tomography. CT-scanned 3D data is directly used for geometrical analysisGeometrical analysis using open-source software, GOM Inspect. Since algorithms used in the GOM Inspect are proprietary in nature, the extracted coordinate data are also analyzed using the computational methods developed by the authors based on least squares technique. The dimension, circularity, and cylindricity of microholesMicroholes are compared with the results obtained from GOM Inspect software and a close match is found.

In this analysis, an investigation and testing work were carried out on the spark EDM of EN-25 material using copper electrodes. Considering the machining parameters such as pulse on time, pulse off time, current, dielectric pressure for machining the effect of these following input parameters on output characteristics like metal removal rate (MRR), tool wear rate (EWR), wear ratio (WR), cylindricity (CYL), circularity (CIR), and perpendicularity (PER). The investigation was carried on with L9 orthogonal array. The effect of each machining parameters on response characteristics was studied independently using trend analysis. From results, circularity has been minimized to decrease of current and increase of dielectric pressure. Cylindricity has been minimized to decrease of current and increase of dielectric pressure. Perpendicularity has been minimized to increase of current and decrease of dielectric pressure.

This paper presents a simple and efficient method for computation of cutting-edge wearCutting-edge wear of a single-point cutting tool in a plain turning operation. It comprises development of an efficient and accurate image processing-based computer algorithm which compares two images of the cutting tool, i.e., before and after its use in the machining operation. The first image has been used as the reference image. Location of the tool in the image was found out using the developed image processingImage processing algorithm. Vertical and horizontal magnifications of the tool image were adjusted such that both the images of the tool have same tool width in terms of pixels. The portion of the images containing tools was extracted and used for the wear computation. The performance of the algorithm was tested by conducting systematic experiments and it was found to be efficient and stable. Only 28 s was noted for the computation of tool wearTool wear based on the images captured by a simple digital camera. The algorithm efficiently removes the noise present in the images of worn-out cutting tool used in real-life conditions.

Industrial Internet of Things (IIoT) is a digital platform to perform machine-to-machine communication, acquire sensor data, analyse, and deliver comprehensive information and also facilitate the manufacturing system to implement smart decisions faster. This paper presents modelling and analysis of an IoT-enabled autonomous manufacturing system based on the performance metrics. Multi-agent interaction has been defined through a generalised control architecture, considering as an autonomous manufacturing system. The number of jobs entering and leaving the machines computes time-dependent performance metrics such as cycle time and work in process using Little’s law. The mean arrival rate of each machine is calculated by evaluating the amount of work and a utilisation factor. The squared coefficient of inter-arrival rates based on successive substitution of job flow from machine x to machine y has also been obtained. This is preliminary work in the process of designing an IoT-enabled autonomous manufacturing system capable of self-learning and executing accurate decision faster.

Carbon fibre-reinforced polymer (CFRPCFRP) composites are broadly utilized in space applications due to their very high specific properties over typical metals and alloys. AutoclaveAutoclave curing is one of the finest composite producing techniques to achieve great dimensional accuracy of the advanced shaped component. The cure shrinkage, which is commonly referred to as warpage or spring-back distortionDistortion, is induced as a result of material thermo-elastic anisotropy during composite laminates manufacturing. In this paper, the distortionDistortion of CFRPCFRP reflectors is estimated using experimental and numerical approaches for autoclaveAutoclave processing. The antenna reflectorsAntenna reflector have been fabricated using HCU200/A45 prepreg and stainless steel AISI 430 as a part and tool material, respectively. The geometric modelling and finite element analysisFinite element analysis (FEA) have been performed for parabolic reflectors using ABAQUS software along with COMPRO plug-in. Thermochemical and stress-deformation analysis has been performed to obtain the deformed shape of the antenna reflectorsAntenna reflector. The laminate thickness has been considered as a process parameter. The experimental and numerical results have been compared and located in sensible agreement with one another.

HydroxyapatiteHydroxyapatite (Ca10(PO4)6(OH)2–HAp) conglomerate with various weight fractions (5, 10, 15, 20 and 25 wt%) is fabricated by reinforcing TiO2 and ZrO2 + TiO2 nanoparticles (20–40 nm). In order to obtain homogeneous mixing of HAp, particles are reinforced using high-energy ball milling (HEBM) at 300 rpm for 1 h, compacted at 100 bar with holding time of 150 s and sintered at 1200 ℃. X-ray diffraction (XRDXRD) analysis, energy-dispersive spectroscopy (EDX) and microstructural analysis using field emission scanning electron microscopy (FESEM) have been carried out on the obtained samples. The mechanical characterization of the composites has been evaluated through flexural strength, compression strength, hardness, young modulus and fracture toughness. The mechanical properties are found to be improved with increasing content of TiO2; however, with increasing content of TiO2 + ZrO2, mechanical properties are found to be improved significantly up to the addition of 20 wt% of reinforcement content. When 25 wt% of TiO2 + ZrO2 reinforcement is added to HAp, the mechanical properties are found to be decreased. The reduction could be due to the increase in dominant smaller particles of ZrO2 and grain size. The improved mechanical properties are correlated with the observed microstructural features.

This research paper investigates the effect of cobalt on the corrosion resistance of electroless Ni–P coating by forming a ternary alloy with Ni–P. The corrosion resistance offered by the ternary coating was measured for coating formed by varying the composition of the bath. The varying bath parameters were the concentration of cobalt source (cobalt sulphate) (A), concentration of reducing agent (sodium hypophosphite) (B) and the temperature (C) of the bath. The corrosion resistance was measured using electrochemical impedance spectroscopy (EIS). Taguchi’s method has been applied with corrosion resistance as response operator to find the optimum resistance to corrosion and the optimum bath parameters, and along with it, ANOVA is done to find significant interactions between factors. The scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDAX) were performed to find the surface morphology and surface composition of the optimized coating.

The carbon fibre reinforcement polymer (CFRP) is widely used in space applications, automobile industries, aerospace and sports equipment because of good specific properties over conventional metals and alloys. AutoclaveAutoclave processing is one of the best manufacturing techniques to achieve high-dimensional accuracy for complex-shaped component. But, due to high initial and processing cost, vacuum-assisted resin transfer moulding (VARTMVARTM) is the alternative manufacturing method. In this research paper, CFRP antenna reflectorAntenna reflectors have been manufactured using autoclaveAutoclave process and VARTMVARTM manufacturing process to evaluate dimensional accuracyDimensional accuracy. The part thickness of laminate and layup orientation has been considered as a processing parameter in reflector manufacturing. The dimensions of the inner surface of the manufactured reflectors have been measured using 3D scanning techniques at the different locations. The deviation between theoretical CAD model and reflector dimensions at each location provides dimensional inaccuracy for the fabricated reflectors. The investigation on the dimensional inaccuracy of cured reflectors manufactured using the autoclaveAutoclave and VARTMVARTM manufacturing techniques has been carried out and the percentage difference has been found within the acceptable limit.

Use of microwave energy for processing of materials is gaining vast popularity due to its inherent superior characteristics like reduced processing time, better control on microstructure and enhanced mechanical properties. In this paper, the interaction of the microwave with metallic powder is analyzed using COMSOL Multiphysics software. Further, the effect of particle size on microwave absorption is also been analyzed. Microwave hybrid heating (MHH) technique is used to heat the metallic powder. Initially, metallic powder gets heated conventionally, i.e., through the heat transfer with separator plate and susceptor material. Once the metallic powder reaches the critical temperature, metallic powder starts to absorb the microwave and volumetric heating takes place. Also, the effects of input power on electric field strength and melting time of charge were analyzed. Further, it was found that as the size of the metallic powder particle is reduced, the time required for melting and casting of metallic powder reduces.

Friction and wear are the main causes observed by manufacturing industries which lead to the replacement of components. The objective of the present work is to investigate the tribological behaviours of Nylon 6 and glass-filled (GF) Nylon 6 composites using a pin-on-disc configuration. Pin materials were fabricated by injection moulding machine and tested for friction and wear against 320 grit size silicon carbide (SiC) sandpaper. The effect of the different load (N), glass-filled content (wt%) and sliding distance (m) were studied for the coefficient of friction (COF) and specific wear rate (SWR). Analysis of variance (ANOVA) procedure was used to find out the percentage contribution of process parameters (load, sliding distance and varying glass-filled content) with the COF and SWR. Process parameters were optimized by hybrid Taguchi-grey relational analysis (GRA) and cuckoo search algorithmCuckoo search algorithm (CSA). There is a close relationship between COF and SWR with wear mechanisms.

Friction stir back extrusion (FSBE) is a novel and an efficient method of manufacturing sounded products by using specialized tool in one step (without melting of scrap). It can be saved about 40% of material, 26–31% of energy consumption, and 16–60% of labor costs compared with conventional extrusion. The main aim of this study is fabrication of hexagonal barHexagonal bar from aluminum alloy scrapAluminum alloy scrap by FSBE. The material used for this study is AA6063 as a scrap and H-13 tool steel as a die. Considered parameters were chamber rotational speed and vertical die transverse speed as major parameter on conventional milling machine. This work has proved the feasibility to extrude hexagonal-shaped bar by using FSBE by fixed die and rotates chamber. So far, none of the researchers carried out experiment by fixed die and rotate chamber in FSBE, and also no one applied FSBE to produce other than circular shape. Aluminum hexagonal-shaped bar is used as a supporter in medical and marine industry, as a raw material to the mass production of hexagonal head aluminum nut and bolt, Allen wrenches, etc. Extruded bar was defect-free, non-blurred grain boundary, and clear surface than the base material. The result showed that the compression strength of extruded sample was higher than the base material. The optimum rotational speed of chamber to produce hexagonal barHexagonal bar with the minimum twist angle is 250 rpm and transverse speed 6.25 mm/min. If the rotational speed increases, twist angle also increased.

The fabrication and mechanical performance of Al-Mg-Si alloy matrix composites reinforced with silicon carbide (SiCSiC) and bagasse fly-ashBagasse fly-ash has been explored in this work. The fabrication and experimental investigation of mechanical properties of aluminium matrix (Al/SiCAl/SiC) composite with and without addition of bagasse fly-ashBagasse fly-ash by varying wt% of reinforcements were investigated. Chemical composition of reinforcement, weighted required amount of matrix and reinforcements, powder mixing, stirring the slurry at 500 rpm speed and 5–10 min were the parameters used to develop the Al/SiCAl/SiC-bagasse fly-ash hybrid composite. Bagasse fly-ash particulates added with 7.5, 10, and 12 wt% SiC were utilized to prepare 10 and 12 wt% of the reinforcing phase with Al-Mg-Si alloy as matrix using stir castingStir casting method. The cast samples were machined for evaluating the properties by performing tensile testing, compression strength testing, and micro-hardness measurement. The results disclosed that the hardness of the hybrid composites increased with increase in bagasse fly-ashBagasse fly-ash content with a maximum increment of 17% observed for the Al6063-7.5% SiC-10% bagasse ash composition (in comparison with the Al-10 wt% SiC-7.5 fly-ash reinforced composition). Tensile strength reduced of maximum value of 90–68 MPa at 7.5 SiCSiC-7.5 bagasse ash compositions.

This present work proposes a novel fuzzy-based multi-criteria decision-making (MCDM) approach for addressing material selectionMaterial selection problem under uncertain environment. The integrated framework integrates fuzzy decision making with evaluation based on distance from average solution (EDAS) MCDM method. Proposed framework fulfills the gap of restricted exploration of fuzzy decision-making tools in the domain of material design. The applicability of the proposed framework has been evidenced through a case study of a material selection of the casting plate used in sand casting. The selection was done considering five material alternatives and seven criteria. The presented fuzzy-based approach considers the objective weights while calculating the weights of the considered criteria.

The compositesComposites developed from natural fibre have brought indisputable advantages over synthetic materials in terms of nontoxicity, efficient waste disposability, comparable strength, etc. Some automotive structures such as in aerospace and motor racing vehicles, strength-to-weight ratio is precisely imperative and fibre-reinforced composite materials are used to develop such structures with critical stiffness and weight sensitivities. The environmental effect and the subsequent failure of the fibre-reinforced polymersFRP (FRP) have led to the study of its different mechanical properties. In this work, the fibre-reinforced composite material was fabricated with hybrid jute–coir fibre and polyester resin matrix embedded with glass/carbon fibres. Tensile and flexural strengthFlexural strength of the developed natural fibre compositesComposites are tested using universal testing machine (UTM) as per the ASTM standards. The sample C2 [jute 75% + coir 25% and carbon 100% of 30% and 15% of total composite composition in weight percentage (wt%)] with yield, ultimate and flexural strengthFlexural strength of 118, 122 and 81.04 MPa in-errantly proved to possess an upper edge over jute–coir–glass compositesComposites upon testing.

In the present work, an attempt has been made to investigate the effect of varying wt% of short carbon fiber on the hybrid carbon–glass fiber/polypropylene (PP) composites. Composites of PP reinforced with short glass fibers and carbon fibers were prepared using two-roll milling machine and compression molding techniques with different vol. fraction and wt. percentage. The wt% and vol. fraction of glass fibers were kept constant, by varying the other two materials. Different mechanical propertiesMechanical properties such as tensile and impact properties were investigated by using suitable experimental setup. In tensile test, with the increase in carbon fiber wt% the strength (MPa) initially decreases but afterward it increases and is giving highest value for maximum wt% of carbon fiber. But for the impact test, the energy absorbed (J) gradually increases by increasing the carbon fiber wt%. From the test results, it shows that the material properties have been improved significantly compared to the polypropylene with only glass fiber, which encourages to use and opt for hybrid composite.

GrapheneGraphene is one of the carbon allotropes which have one atom thickness. It is a monolayer of carbon atoms, which are bonded in a two-dimensional hexagonal lattice. It is a unit layer of graphite; stacking the monolayer grapheneGraphene one over another forms the graphite. The exceptional electromechanical properties of grapheneGraphene attracted the researchers and scientists to explore the wide application areas so that the properties of grapheneGraphene could be harnessed. In this regard, the present paper analyses the perfect single-layer grapheneGraphene sheet (SLGS) and defective grapheneGraphene sheet by depicting the effect of temperature variations on the fracture strengthFracture strength of both of the sheets. To this end, the molecular dynamics (MD) simulations based on AIREBO interatomic potential field and Nose–Hoover thermostat technique are carried out. It is concluded by the study that with the increasing temperature, the fracture strengthFracture strength of the grapheneGraphene reduces remarkably. It is also evident that introducing random vacancy of 2.5% in perfect grapheneGraphene causes the yielding phenomenon at lower strains which remains absent in the perfect grapheneGraphene. Also, the defective grapheneGraphene shows the ductile fracture, confirming considerable yielding before complete fracture.

In this study, both experimental and numerical investigations were performed for plasma preheating of AISI 1018 low carbon steel plates. The finite element (FE)Finite element (FE) software package ABAQUS 6.14 was used to perform the transient thermal analysis using Gaussian distributionGaussian distribution as a heat source for plasma preheating. In this FE model, temperature-dependent thermal material properties of low carbon steel (AISI 1018) were used. The influence of different parameters, i.e., traverse speed, plasma arc power on thermal history was determined. Experimentally obtained transient temperature distribution and peak temperature compared fairly well with FE results with a maximum percentage error of around 6.8% and 7.53%, respectively.

This paper presents a reduced-order finite element analysisFinite element analysis of rough surfaceRough surface contact. Frictionless, elastic contactElastic contact between a rough deformable block with Gaussian roughness and a rigid flat plate is considered. An equivalent one-dimensional rough surfaceRough surface of a two-dimensional rough surfaceRough surface is generated using MATLAB. Generated rough surfaceRough surface is superimposed on ten layers of generated mesh of the block and analysis is done in commercial finite element software AbaqusAbaqus. Four-noded quadrilateral elements with reduced-order integration are used to decrease the computational time. The rigid plate is placed close to the largest asperity of the rough surfaceRough surface and is then displaced in small steps. Contact force and real area of the contact are calculated. Results are compared with the results of the full-scale finite element analysisFinite element analysis in the literature and are found to be in good agreement.

In fiber-reinforced plastics (FRP) laminate, different laminae are adhesively bonded to each other. The interfaces between plies are weak because these are resin rich; therefore, there is a low-resistance path for crack propagation. As a result of this, delamination is a frequent mode of failure in the FRP laminate. The drillingDrilling of laminated FRP is always associated with delaminationDelamination damage; therefore, delamination-free drillingDrilling is a major concern for aerospace industries. Experimental investigations of drilling-induced delamination have been widely studied in the literature, whereas very few studies are available related to its modeling. In this paper, the effect of the chisel-edge length of drill-bit on push-out delamination was studied. Finite element modeling (FEM) approach was used to model interfaces of laminae, and it was further extended to model delaminationDelamination in drillingDrilling of FRP laminate. Cohesive zone method (CZM) based on traction–separation law was used in FEM to model the interfaces of laminae. It was observed that load-carrying capacity of beam in double cantilever beam (DCB) test reduced by 50% for ‘1 mm’ initial crack length. Also, push-out delamination increased by around 10% with an increase in the chisel-edge length of drill bit from ‘0 mm’ to ‘0.35 mm.’ The FE models developed in this work were able to simulating delamination phenomenon with enough accuracy.

Electron-beam welding, one of the high-energy density welding processes, is preferred for welding of nuclear, aerospace, and automotive materials. However, the input–output modeling of the welding is a challenging problem faced by many of the welding experts because of addition of new alloys to the industries. Soft computing techniques have been evolved in recent days to address this issue efficiently. This paper discusses two potential approaches of fuzzy inference system (FIS)-based neuro-fuzzy system for modeling of electron-beam welding response parameter. The following adaptive neuro-fuzzy inference systems (ANFIS): grid partition-based fuzzy interference system (G-ANFIS) and subtractive clustering-based fuzzy inference system (S-ANFIS) have been incorporated for the determination of depth of penetration in electron-beam welded copper plate in bead-on-plate configuration. In this study, the performances of above networks are compared on the basis of accuracy and computation time. Coefficient of correlation for S-ANFIS and G-ANFIS are found to be 0.98 in both approaches. Prediction of S-ANFIS is found to be 4 and 6% more accurate than results of G-ANFIS and regression model, respectively. Grid ANFIS consumes around 42 min to complete the computation, while it takes only 9.819 s for S-ANFIS. Based on the comparison, it is observed that the S-ANFIS model has the better prediction capability and less computational complexity than G-ANFIS and nonlinear regression model.

This paper presents a numerical analysis of solid particle erosionErosion of a rough surfaceRough surface. A total of ten particles are modelled to impact the target surface. For validation, first a smooth surface is impacted with rigid particles and the erosion results are compared with experimental results in the literature. After validation, erosionErosion of rough surfaceRough surface is simulated using the finite element software ABAQUSAbaqus. Rough surfaces with different average surface roughness are generated using inbuilt fast Fourier transform and random distribution functions in MATLAB. The coordinates of the generated rough surfaces are then imported to and superimposed on the mesh of the target surface generated in ABAQUSAbaqus and finite element analysisFinite element analysis is performed. It is observed that surface roughness affects the erosionErosion rate significantly. For impact angles of 30° and 40° erosionErosion is found to be less than that of the smooth surface.

This paper reports finite element methodFinite Element Method-based numerical simulations of nanoindentation of SiliconSilicon to extract the mechanical propertiesMechanical Properties, viz. Young’s modulus and hardness. The simulations were carried out by using the Drucker–Prager constitutive model assuming a rigid spherical indenter of radius 300 nm to mimic the Hertzian contact which is typically observed underneath the Berkovich indenter. The dispalcement controlled boundary conditions comprising the depths of indentation as 45, 75, 95, 115, 130, and 140 nm were applied. Oliver–Pharr analytical method was used to obtain load-displacement plots. By using these plots, the values of Young’s modulus and hardness were estimated. The results from the developed finite element simulation have also been validated by using the published experimental results. The estimated results from our simulations were found to be fairly matching with the experimental results. It was noticed that the FEM-based simulations provide an economical and fast option to the physical experiments in the estimation of mechanical propertiesMechanical Properties of a material.

Three different patterns (rectangular-serpentine, U-serpentine and V-serpentine) of microchannels were modelled to investigate the fluid flow and heat transfer characteristics using the commercially available finite element analysis software—CFD Fluent. The microchannel models were based on 0.525-mm-thick silicon wafer substrate. The hydraulic diameter (0.4 mm) and channel length (114 mm) were kept constant in all the three different patterned microchannels to compare the performance of the microchannels. Three-dimensional (3D) simulations were performed to simulate near practical condition using the conjugate method in which heat transfer was considered in both solid and fluid zones. Reynolds number was varied in the range of 100–400, and uniform heat flux (30 kW/m2) was applied at the bottom wall of the microchannels to investigate the effect of microchannel pattern on pressure dropPressure drop, temperature, velocity profileVelocity profile and heat transfer coefficientHeat transfer coefficients. Results confirm that the higher heat transfer coefficientHeat transfer coefficient was obtained in U-serpentine microchannel, indicating better performance among the three.

In this paper, a comparison of GPU-based linear solverLinear solver libraries for the solution of sparse positive-definite matrices is presented. These large sparse matrices arise in a number of computational disciplines seeking a solution for partial differential equations. The solution of these matrices is often a time-consuming process that can be reduced by parallel computingParallel computing. Since the development of GPU for general-purpose computing, a number of numerical solver libraries have evolved that can accelerate the solution procedure. The performance of three solver libraries has been evaluated in this paper for five different test matrices. These test matrices have been taken from different application domains with different sparsity patterns. Results demonstrate a higher speedup from the iterative solver over the direct solver on GPU and also over a multithreaded CPU implementation.

Multi-Objective Evolutionary Algorithms (MOEAs) have been successful in solving mathematical and real-world multi-objective optimization problems by evolving a set of optimal solutions, which are known as Pareto-optimal solutions. However, there are certain limitations with those algorithms such as slow convergence, lack of effective terminating condition to name a few. To address such challenges, hybrid MOEAsHybrid multi-objective algorithm are being designed and studied where the global exploration power of MOEAs are combined with local exploitation modules of various numerical optimization techniques. However, hybridization itself brings new challenges in its implementation. In this work, a hybrid MOEAHybrid multi-objective algorithm is presented in which random mutationsMutation are performed on the initial population to start with a better and diverse set of solutions. Moreover, a local searchLocal search module is coupled to execute periodically on a least crowded non-dominated solution at a certain interval of generations. The proposed algorithm is tested on a set of benchmark multi-objective optimization problems and compared with the NSGA-IINSGA-II. The convergence plots demonstrate the superiority of the proposed algorithm over NSGA-IINSGA-II.

Vehicle routing problemVehicle routing problem (VRP) is an NP-hard problem, which looks for the optimal route for vehicles to deliver goods to the customers with minimum transportation cost. Since transportation and logistics incur a good percentage of cost on to the basic price of the products delivered, VRP has been an interest in many organizations and also for many researchers. Due to the limitations of exact algorithms, the heuristics/meta-heuristics have been a choice for evolving an optimal solution for VRP. In this paper, various local search heuristicsLocal search heuristics are coupled with genetic algorithmGenetic algorithm (GA), and two more intense local search heuristicsLocal search heuristics are proposed. GA is tested on six different capacitated VRP instances. Results demonstrate the efficacy of GA in obtaining the solutions close to the best-known solutions that too in less computation time.

The effect of adhesive properties on performance of spur gear made of adhesive system referred to as adhesive spur gear is investigated. In addition, the repair ability and reusability of adhesive spur gear towards sustainability are also investigated. Two-part epoxy adhesive system constituting resin and hardener was used to fabricate spur gear samples. In order to modify adhesive properties, the hardener to resin ratio was varied. The repair ability and reusability of spur gear made by the adhesive system were checked by breaking a few teeth of the adhesive spur gears and repaired by adhesive. The repaired gears were tested and compared with the performance of actual spur gears made of adhesive. The gears were tested by a gear test rig developed indigenously. The performance of the gears with different hardener to resin ratios was evaluated by monitoring the number of cycles. The results show that the number of cycles increases with decrease in hardener to resin ratio. This is due to the better strength of the adhesive system with the resin-rich formulation. There is not much difference in performance between repaired gear and the corresponding actual gear. This ensures the sustainability of adhesive gears over conventional polymer gears.

Wonji Shoa Sugar FactoryWonji Shoa Sugar Factory (WSSF) is one of the top sugar factories in Ethiopia which produces sugar and electricity from sugarcane using three critical plants: mill plants, sugar processing plant, and a cogenerating power plant. Among three plants, the mill plant is the most important plant used to crush the cane for separating sugar juice from bagasse. In this plant, Fibrizer hammerFibrizer hammer device is used for cruising sugarcane. The Fibrizer performs the major share in milling process for fibrizing the chopped cane after set of cane knives using rotating knives. Most of the times, WSSF is facing breakages of Fibrizer hammerFibrizer hammer by which losses incurring to the factory. The main aim of the paper is to analyze the failure causes of existing Fibrizer hammerFibrizer hammer with respect to design and modify the necessary changes in design for Fibrizer hammerFibrizer hammer at WSSF. By which, get high preparation index (PI)Preparation index (PI) and optimize in power consumption and cost. In addition, hardness of the existing Fibrizer hammerFibrizer hammer was tested to know the mechanical strength. For modification of existing Fibrizer hammerFibrizer hammer: comparison was made in terms of design, and load along with harmonic simulation analyses performed using finite element analysis. The results from finite element analysis revealed that the modified Fibrizer hammerFibrizer hammer having minimum deformation, minimum shear stress, and more centrifugal force has a relation to achieve better preparation index.

Laminated composite has gained popularity (despite of their higher cost) in high-performance products that need to have high corrosion resistance, good thermal stability, excellent fatigue resistance, lightweight and high specific strength to take harsh loading conditions such as aerospace components. Based on the literature survey, it is observed that Tsai–Wu criterion is widely used because of its accuracy. In the current study, finite element analysis is being carried out by using MSC Nastran and MSC Patran to identify the critical ply location and strength of first ply failureFirst ply failure within laminated composite material plates. Tsai–Wu failure criterion is used to predict the maximum failure indices on each ply of laminated composite material. The results obtained from FEA are validated by comparing with the experimental result.

Porous structures based on triply periodic minimal surfaces (TPMS) have occurred as appropriate candidates for scaffold design with high level of porosity and promising strength for bone replacement. This work describes a suitable procedure for design and modeling of 3D architecture of TPMS-based gyroidGyroid and primitive structures and identifying the optimal architecture for scaffold designing. Different models with varying porosity were reconstructed and analyzed to access the effective elastic moduli and compressive strength of each model. An optimal model that can be utilized in bone tissue replacement is identified eventually. Ti6Al4V which is considered as the best material for producing implants in conjunction with biocompatibility and strength is used in the study. The compression test performed by FEM revealed that the scaffold models with porosity level of 65 and 60% are best suited for cortical bone replacement and the model with 90% porosity can be used on the anatomical location, which are more inclined to cancellous bones.

The primary function of kidneys is to remove waste and other impurities from the blood of a human being on a daily basis. When the kidneys stop functioning properly, the toxins from the blood have to be removed through an external device, dialyser. The dialyser mimics the kidney and draws the blood out of the patient, purifies the blood and infuses them back into the patient’s body. When the blood is infused back to the human body, it has to be at 37.6 ℃ failing which would lead to hypothermia, a fatal condition. To avoid this fatal condition, the body is heated to human body blood temperature 37.6 ℃. The blood flow rateFlow rate and heat supply in the bloodline can vary over a wide range but still the blood has to be heated to 37.6 ℃ which is human body blood temperature. To raise the human body temperature to 37.6 ℃, a sub-component in the dialyser machine called blood warmerBlood warmer takes care of heating. Since it is a medical device which interacts with the patient, the precision of 0.5 ℃ is expected over a range of flow ratesFlow rate and heat supply based on patient’s medical condition. The scope of this work is the design of a precise blood warmerBlood warmer which is effective than existing. The multiphysicsMultiphysics simulations helped the engineers to visualize, observe and understand the physics involved during the design stage.

Axle-mounted disc brakes are generally employed in high-speed trains owing to the lesser weight and sustainable thermal properties. Most widely used material for manufacturing of the disc brake is grey cast iron (GCI), because of its availability. However, it being a brittle material has certain limitations. Hence, an aluminium composite material (AlSiC) is considered for analysis under different loading conditions. Three models of brake discs are developed on which both structural analysis and coupled analysis were done and results are compared.

This paper is concerned with the development of model for the finite element analysis of the conical space adapterConical space adapter which is subjected to axial compression. It also provides the information about the parameters required for generating the input for modelling the structure. Analysis is performed using Ansys, i.e. software for finite element analysisFinite element analysis. The results of analysis include the behaviour of the adapter under axial compression, e.g. stresses in the helical and circumferential ribs, displacement of the space adapter, critical buckling loadBuckling load and global buckling. Modal analysis has been carried out to study the modes of vibrations and obtain the frequency of vibration of the structure.

Rotational autofrettageRotational autofrettage is a potential strengthening technique for thick-walled circular disks/cylinders used in many engineering applications. In particular, the rotating disks used as a rotor in an aircraft engine, rotating impeller wheel of a compressor and fasteners in high pressure pipelines are the important application areas, where rotational autofrettageRotational autofrettage is useful in mitigating the detrimental tensile stresses during operation. The process induces compressive residual stressResidual stresses in the disk on unloading a previously applied plastically deforming centrifugal load. The amount of residual stressResidual stresses generated during the process depends upon different influencing parameters. The geometrical dimension of the disk, rotational speedRotational speed and material properties are the important parameters to be considered for assessing the effectiveness of rotational autofrettageRotational autofrettage of a disk. In this paper, a parametric study of the different influencing parameters during the rotational autofrettage of a thick-walled axisymmetric circular disk is carried out.

Modern aircrafts, automobiles, space crafts, etc., need light weight and high-performing structures or materials to reduce the total weight of the structure without compromising in strength which highly influences the efficiency of that structure and fuel cost associated with it. Thus, fiber-reinforced polymer (FRP) laminates are the most suitable materials for these kinds of applications due to their high specific strength to weight ratio which is better than many other conventional metal or alloy materials. But these materials are highly prone to catastrophic and sudden failure because of their unpredictable and undetectable crack growth and formation in the laminate structure. These undetectable cracks, also known as barely visible impact damage (BVID), which are induced into the laminate under low velocity impact. Example includes dropping of a tool in an assembly line. Low velocity impact (LVI) is a highly complex phenomenon as it consists of subsurface micro cracks (fiber and matrix cracking), debonding, delamination, and fiber breakage. Due to anisotropic nature of the material, prediction of damage induced becomes difficult. Hence, in this numerical analysis, LS-DYNA is used to carry out the LVI loading onto a bidirectional plain woven glass fiber-reinforced polymer (GFRP) laminate using a hemispherical striker of mass 20 kg with a nose radius of 5 mm impacted at a velocity of 2 m/s. During the analysis, fully constrained circular boundary condition (FCCBC) is used and the radius of the circular boundary condition (CBC) is varied from 15 to 35 mm with an increment of 10 mm. Effect of variation in boundary condition diameter on damage area is examined using von Mises stresses, energy versus time, force versus time, and displacement versus time graphs.

Process capability indices play a very important role in the control and the improvement of quality characteristicsQuality characteristics of products during the production process. Various process capability indices have been developed for quality characteristics which follow normal, Weibull, exponential and other distributions. Many researchers have also developed process capability indices for quality characteristics which follow bivariate normal and exponential distributions, respectively. Some of these indices are being used by industries for the quality improvement of products during the production process for competing in global markets. Some quality characteristics of the products should be treated as discrete random variables following distributions like geometric distributionGeometric distribution rather than widely known continuous distribution like normal. Such situations are encountered while dealing with quality characteristics like number of operations before the failure of electrical, electronic or mechanical switches and components. The control and the improvement of such quality characteristics of such products during the production process, in order to ensure the conformity to the specification (usually one-sided), are quite important. No much work has been done so far to develop process capability indexProcess capability index applicable to such quality characteristics following the geometric distribution. In this paper, the author proposes a process capability index for a number of successes or operations before the first failure of a component or product assumed to follow a geometric distribution and derives the expectation and variance of the estimated index. The optimal choice of process capability interval related to the said index has also been discussed. The said process capability index may be low for a highly capable process and for the minimum variation of the index, the percentage area lying outside natural tolerance limit may be low as 0.02, and the probability of successes or operations before the first failure may be high as 0.99.

The submerged arc weldingSubmerged arc welding (SAW) is an automated process that is capable to weld thick and thin plates of steel and non-ferrous materials due to its ease of operation, less spatter and high deposition rates. SAW is extensively used to fabricate bridges, pipe lines, pressure vessel construction, ship building and surface cladding. In present study numerical simulation on effect of welding speed on residual stressResidual stresses for SAW with square butt geometry of austenitic stainless steelAustenitic stainless steel is explored. A moving heat source model considering heat generation is used in this present study. The element birth and death technique is used to incorporate the effects of filler metal deposition. The peak temperatures observed in experimentation were correlated with that of numerical results and the variation was observed to be 4.77%. At higher welding speeds the low peak temperatures were observed which is due to less heat penetrating into the joint. It was observed in the present study at higher welding speeds the residual stressResidual stress and von Mises stress were in increasing trend whereas normal and transverse stresses are negligible along the weld line.

The present study deals with stochastic nonlocal non-dimensional natural frequencies of single walled carbon nanorodsCarbon Nanorods and rotating cantilever beam. In this study, the chordwise bending–vibration behavior of nanocantilever is analyzed. The nonlocal parameter focused on the small-size effects when dealing with nanosize structures such as single-walled carbon nanotubes (SWCNTs). The Eringen’s nonlocal elasticityNonlocal elasticity theory in conjunction to the governing differential equations are utilized to solve the problem. The stochastic nonlocal natural frequencies for rotating nano cantilever are observed by employing the differential quadrature method (DQM). The effects of the scale is computationally analyzed based on Monte Carlo simulation (MCS). In another case free longitudinal frequency of a nanorods considering two types of boundary condition is observed, namely, clamped-clamped and clamped-free. The longitudinal vibration of the system are described by a set of partial differential equations, derived by using D’Alembert’s principle and using by employing Fourier infinite series in conjunction to separation of variables. The nanoscale effects implement a important role on the frequency response of nanorods subjected to rotation. The statistical analysis are carried out based on stochastic input parameters such as material properties (elastic modulus, density) and geometric properties (length).

In today’s world, one of the major problems faced by the rice-milling industries is breakage of rice during processes like de-husking/de-hulling, whitening, and polishing. For designing of milling machinery and for reducing the breakage of different rice varieties while processing, it is important to understand the rupture force of rice kernels of different varieties under the three-point breaking testThree-point breaking test. In this study, the different varieties of rice grains with different fissure conditions were investigated. The rupture force investigated by using three-point breaking testThree-point breaking test which is conducted on Instron UTM with specially designed adjustable support fixture, in which span can be adjusted for different varieties of rice grains. Five brown riceBrown rice varieties—Rashi Poonam, Kolam, Komal, Basmati, and Daptari tested at a rate of 1 mm/min. The finite element analysisFinite Element Analysis has helped to validate the result of the flexural stresses in the rice grain induced during test and then the crack propagation is simulated in the analysis. It was seen that out of the five rice varieties under tests, Rashi Poonam has the highest average rupture force of value 32.29 N. The results obtained from this test and computational analysis can help for developing methods and types of equipment used for whitening and polishing processing of rice with different varieties.

Composite overwrapped pressure vessel (COPV) is widely used in aerospace industry to contain pressurized gases. The behaviour of pressure vessel components (liner and composite overwrap) at applied pressure and potential failures during its operation requires adequate study. The finite elementFinite element (FE) analysis is performed for potential failures occurring in a 420 mm diameter aluminium alloy (AA) 6061-T6 lined spherical pressure vesselSpherical pressure vessel. In the present study, the design of spherical liner with apt manufacturing techniques is presented. The liner contribution towards sustaining the minimum burst load is determined and liner burst test is conducted to check the location of failure. Further, typical liner failuresLiner failure like buckling and bond failure occurring due to inefficient contact between the liner and composite overwrap, which eventually forms a debond region are also studied. The liner burst pressurization results predicted the location of failure in liner at transition region as the liner is undergoing thickness changes in that particular region. The mode of liner buckling, buckling load is predicted when liner is subjected to compression during depressurization cycle. Further, at debond region, the liner is unable to transfer pressure load effectively to composite overwrap experiencing severe deformation.