Designing size-controlled air cavities to reduce iron losses of 3D printed ferromagnetic parts: Modelling and experimental results

Abstract

We studied the effect of cavity insertion to reduce iron losses into Fe-2.6wt.%Si ferromagnetic components fabricated by Laser Powder Bed Fusion (L-PBF) 3D printing process. Finite Element Method (FEM) simulation was used to understand the impact of various cavity configurations on eddy current losses and to identify design guidelines. Results highlight the dependence of losses on eddy current path length, which can be expressed by simple geometrical design parameters. Finally, L-PBF samples were magnetically characterized up to 500 Hz. A good correspondence between experimental data and modelling results is observed. A torus designed with six external cavities allowed the reduction of the losses by 60 % compared to a bulk specimen (0.5 T; 500 Hz).