Study of parametric effect on laser directed energy deposited Austenitic steel and Inconel functionally graded material

Abstract

In this paper, the effect of process parameter on functionally graded materials (FGMs) of Inconel 625 (IN625) and Austenitic steel (SS304L) deposited by laser directed energy deposition (LDED) are investigated. For this purpose, FGM walls of different gradient of mix of IN625 and SS304L at different layers are deposited on Austenitic steel (SS316L) substrate at different sets of process parameters. For this study, the process parameters considered are laser power ( PL): 1000, 1300 and 1600 W, and scanning speed ( v): 0.3, 0.5 and 0.7 m/min. Deposited samples are then subjected to different tests such as energy dispersive spectroscopy (EDS), microhardness, scanning electron microscopy (SEM), X-ray diffraction (XRD), optical microscopy (OM), and nanoindentation. Tests performed on the samples revealed different effects of parameters on the deposition of the FGM wall. Based on the comparison of results of mechanical and metallurgical tests, it is observed that either at PL = 1300 W and/or v = 0.5 m/min, among the considered process parameters, show comparatively better results than the others.