Statistical Analysis of Clad Geometry in Direct Energy Deposition of Inconel 718 Single Tracks

The present study investigates and estimates the effect of process parameters on the clad geometry of Inconel 718 single tracks deposited using the direct energy deposition technique. Three major process parameters, i.e., laser power (P), scanning speed (V), and powder feed rate (F) are varied systematically at different levels and investigated their effect on clad geometry. The clad geometrical characteristics considered are clad width (w), clad height (h), penetration depth (b), and wetting angle (theta). Empirical models are developed with the help of multiple regression analysis based on the experimental results, to correlate the input parameters and output geometry. Analysis of variance is performed to check the influence of individual parameters and their interaction effects. The models are validated by the coefficient of determination value (R-2) which is above 0.87 in all the cases and residuals are distributed within +/- 10%. Further investigations revealed a linear relationship of the clad width with normalized surface enthalpy. The clad height and wetting angle have shown a linear variation with the line mass.