Finite Element and Discrete Element Analyses of Anisotropic Powder Compaction for Axial Flux Motor Cores

This study investigates the compaction behavior of anisotropic, plate-like powders used in axial flux motor cores through a combined FEM–DEM approach. A porous continuum FEM model captures stress and density evolution during die pressing, revealing strong gradients along the compaction direction, with higher stress and densification near the upper punch and reduced compaction in the lower region. Guided by these results, DEM simulations examine particle packing, orientation, and contact pressure in representative zones. The DEM analysis shows that higher local pressure promotes denser packing and in-plane particle alignment near the upper punch, while the lower region exhibits more random orientations and lower contact forces. As a result, the multi-scale FEM–DEM framework clarifies how anisotropic particle behavior governs local densification and offers practical guidance for die design and process optimization to achieve more uniform density and controlled magnetic-property-relevant particle alignment in axial flux motor cores.