Multiphysics Modeling And Experimental Validation Of High-strength Steel In Laser Powder Bed Fusion Process

Laser powder bed fusion (LPBF) is a subset of the additive manufacturing process in which a laser beam selectively joins the metal powder into a desired part in a sequential layer process. Owing to its complex nature of rapid heating and cooling of the melt pool, there is a need to understand the melt pool behavior and its effects on the final manufactured part. A densely packed powder bed is highly desirable for fabricating a superior part using the LPBF process. In this work, discrete element model was used to generate powder beds with realistic powder properties and various factors affecting the packing density were studied. The powder beds generated were then irradiated with a high-power laser source to selectively melt the powder particles to study the melt pool dynamics using volume of fluid method. The effect of laser parameters like laser power and scan speed on the melt pool was studied using single-track and multi-track simulations. Multi-layer simulations were performed to replicate the actual LPBF process. The simulations were in close agreement with actual experimental efforts.