Finite element modeling of machining-induced microstructure evolution of IN625 superalloy fabricated by laser-based powder bed fusion

Abstract

The surface quality of components fabricated via laser-based powder bed fusion (L-PBF) is highly dependent on the post-machining technique. This study aims to investigate the microstructure evolution of the turning-affected subsurface layer of the IN625 superalloy manufactured by L-PBF with the assistance of the finite element analysis (FEA). A finite element model with integrated user-defined subroutine VUSDFLD was created for numerical modeling of the dislocation density and grain size evolution due to turning operation. The simulation results regarding grain size and the depth of the affected layer were validated against the experiments. This study shed some light on the metallurgical behavior evolution when turning of L-PBF of nickel-based superalloy based on the proposed material microstructure model.