SiC Reinforced AISI 434L Stainless Steel Thin-Wall Structure Fabrication by TIG-Aided Powder Bed Fusion Arc Additive Manufacturing (TIG PBF-AAM) Method

The potential of tungsten inert gas-aided powder bed fusion-type arc additive manufacturing (TIG PBF-AAM) technique in the fabrication of thin-wall structure using SiC (0, 5, 7.5, 10 wt pct) blended AISI 434L steel powder has been demonstrated. The acceptance of the method can been justified through the strong interlayer bonding, between the deposited layers, and favourable mechanical properties of the fabricated part, despite the limitations like geometrical inaccuracy, discontinuity and cracks in the deposited layers. An outstanding deposition rate (1.3 kg/h) makes the process close contender to TIG-based wire arc additive manufacturing technique (1–2 kg/h). Depending on the SiC content, the formation of cellular and/or flower-like dendritic structure, or reinforced particle-like structure indicates the possibility of SiC particle dilution within the matrix phase. The XRD analysis shows the presence of α-ferrite and martensite phases for 0 wt pct SiC reinforcement. However, cubic-SiC in combination with some metallic carbides and intermetallic phases was detected for SiC incorporation with AISI 434L steel. The fabricated composite structure exhibited high microhardness (up to 626 HV_0.05) and more than two times improved wear resistance than the AISI 434L SS structure. Nevertheless, a marginal reduction in the corrosion resistance was noticed in the SiC-incorporated specimens.