Numerical investigation of thermal loading on stainless steel during laser powder bed fusion

Abstract

The objective of this study is to establish a simulation approach based on finite element modeling (FEM) of the process for obtaining parts by additive manufacturing (AM). This approach makes it possible to evaluate the influence of different parameters such as inter-track, scanning speed and laser power of the "Laser Powder Bed Fusion L-PBF" process on the thermal characteristics of AISI 316L stainless steel parts. A thermal analysis is carried out taking into account the sequence of material deposition and scanning of the laser beam similar to the actual process. The simulation result, validated experimentally, made it possible to predict the distribution of the temperatures at the inter-layers and inter-tracks and the morphology of the molten pool. These results allowed us to provide physical explanations of material discontinuities, degrading the mechanical behavior and often encountered in additive manufacturing. This allows the identification of a range of volumetric density of energy (VED) leading to better continuity of matter.