Modeling and Simulation of Microstructure Evolution for Additive Manufacturing of Metals: A Critical Review

Beam-based additive manufacturing (AM) of metallic components is characterized by extreme process conditions. The component forms in a line-by-line and layer-by-layer process over many hours. Locally, the microstructure evolves by rapid and directional solidification. Modeling and simulation is important to generate a better understanding of the resultant microstructure. Based on this knowledge, the AM process strategy can be adapted to adjust specific microstructures and in this way different mechanical properties. In this review, we explain the basic concepts behind different modeling approaches applied to simulate AM microstructure evolution of metals. After a critical discussion on the range of applicability and the predictive power of each model, we finally identify future tasks.