MIM-like additive manufacturing of Fe3%Si magnetic materials

Abstract

The performance and energy efficiency of electro-mechanical converters are strongly bound to the properties of their magnetic cores. The latter are mostly made from stacked laminations of soft magnetic materials, such as Fe3%Si, which limits the core geometry design. However, when complex geometries are required, usually forging processes may be employed but with very low silicon steels (<0.5%) to be able to forge the steel. In that case, the low silicon content yields to higher electrical conductivity and then to higher eddy current loss. In this work, an additive manufacturing technique allowing to build complex geometries is studied with Fe3%Si magnetic materials. The fabrication process allows to obtain green parts which are then densified through debinding and sintering steps. The magnetic characterization is performed on toroidal cores and allows to observe a high level of magnetic induction and relative permeability. Finally, the impact of the printing strategy on the magnetic performances is investigated.