Numerical simulation and experimental study on austenitic stainless steel by laser assisted metal deposition (L-MD)

Abstract

The Laser assisted metal deposition (L-MD) is under the category of direct energy deposition (DED) process, and produce components with excellent metallurgical properties and full density. The temperature induced in the melt-pool, temperature gradients, solidification rate and laser interaction with powder material is very difficult to understand during L-MD process. Therefore, finite element analysis is done on L-MD to understand thermal behaviour which governs the microstructure characteristics (grain size and morphology). The input parameters of L-MD are scanning rate, powder feeding rate and laser power on the clad height and width and also investigated the variations of solidification rate and temperature gradient at each process parameter. The significant rise in clad width and height with laser power and powder feeding rate whereas descend with scanning rate are observed. The simulated clad width and height are well agreed with the experimental results. The scanning rate shows the significant impact on the magnitude and morphology of the microstructure.