Establishing Property-Performance Relationships through Efficient Thermal Simulation of the Laser-Powder Bed Fusion Process

In order to learn how to modify additive manufacturing designs and processes to ensure lab-scale specimens and final components have similar properties, it is important that process-property relationships be established through thermal simulations. In this study, two unique numerical methods for efficiently predicting the thermal history of additively manufactured parts via simulation are presented and validated. These numerical methods make use of an idealized, constant/uniform heat flux which is applied at each new layer and ‘bulk-layers’ which consist of several layers and allow the use of coarser meshes and longer time steps. To demonstrate and test the numerical methods, simulations are ran for the laser-powder bed fusion (L-PBF) of stainless steel (SS) 17-4 PH parts with different volumes. Simulation results indicate how to modify L-PBF process parameters, specifically time intervals, to better ensure a similar thermal history, temperature, temperature gradient and cooling rate, of different sized/shaped parts.