Empirical-Statistical Modeling and Prediction of Geometric Characteristics for Laser-Aided Direct Metal Deposition of Inconel 718 Superalloy

It is requisite in laser-aided direct metal deposition (LADMD) to investigate the influence of three key process parameters (laser power, scanning speed, and powder feeding rate) on geometric characteristics of single-track deposits so as to acquire LADMD deposits with minimum defects and controlled geometric accuracy. In this study, LADMD of Inconel 718 superalloy was studied and the dependency of geometric characteristics on key process parameters was investigated as a combined parameter (P^αV^βF^γ). A simple empirical-statistical modeling was used employing linear regression method. The results showed that the geometric characteristics had a linear relationship with a combined parameter including three/two key process parameters together. The height and wetting angle of single-track deposits were dependent on P²V⁻¹F¹ and P^3/2V⁻¹F¹, respectively. The width of single-track deposits was dependent on P²V^−1/4 but it was independent of powder feeding rate. The dilution of single-track deposits depended on V¹F⁻¹ while laser power had no effect on it. A process map is developed to enable optimization of the process parameters in LADMD process of Inconel 718.