Physics-Based Modeling and Predictive Simulation of Powder Bed Fusion Additive Manufacturing Across Length Scales

Abstract

Powder bed fusion additive manufacturing (PBFAM) of metals has the potential to enable new paradigms of product design, manufacturing and supply chains while accelerating the realization of new technologies in the medical, aerospace, and other industries. Currently, wider adoption of PBFAM is held back by difficulty in part qualification, high production costs and low production rates, as extensive process tuning, postprocessing, and inspection are required before a final part can be produced and deployed. Physics-based modeling and predictive simulation of PBFAM offers the potential to advance fundamental understanding of physical mechanisms that initiate process instabilities and cause defects. In turn, these insights can help link process and feedstock parameters with resulting part and material properties, thereby predicting optimal processing conditions and inspiring the development of improved processing hardware, strategies and materials. This work presents recent developments of our research team in the modeling of metal PBFAM processes spanning length scales, namely mesoscale powder modeling, mesoscale melt pool modeling, macroscale thermo-solid-mechanical modeling and microstructure modeling. Ongoing work in experimental validation of these models is also summarized. In conclusion, we discuss the interplay of these individual submodels within an integrated overall modeling approach, along with future research directions.

An Application-Driven Method for Assembling Numerical Schemes for the Solution of Complex Multiphysics Problems

“…As a final remark, we note that similar models for resolving the melt pool dynamics in laser powder bed fusion have been developed using mixed formulations of the finite element method. For example, Meier et al developed a custom, high-performance finite element simulation code called MeltPoolDG based on the discontinuous Galerkin method as well as a mixed FEM to resolve the melt pool on the powder bed scale [102,103]. Other recent developments include a finite element model on multiple grids to capture the governing physics [104], and a space-time FEM code that is based on a Petrov Galerkin approximation [105].…”

A simple yet consistent constitutive law and mortar-based layer coupling schemes for thermomechanical macroscale simulations of metal additive manufacturing processes

“…Existing modeling approaches for PBFAM are often distinguished by the modeled length scales (see overview in [29,30]). Macroscale or part-scale models determine residual stresses or dimensional warping.…”