Improved properties of soft magnetic composites with hollow microstructures

Abstract
Soft magnetic composites (SMCs) possess promising electromagnetic characteristics and attract intense research and application interest in the engineering community. Fabrication of composites with customized architecture is feasible due to the recent advances in additive manufacturing (AM) techniques. The systematic progress of computational optimization has opened up the possibility of devising such structures. This article presents newly structured SMCs which can recently be possible by AM. The effective permeability and eddy current losses are studied in comparison to those properties of traditionally fabricated SMCs. With this hollow inclusion arrangement, for the same iron volume fraction, the effective permeability can be greatly enhanced (more than tenfold) while the eddy current losses decrease considerably. For the same magnetic property, we save iron material, make the composite lighter, and benefit from a lower level of eddy current losses with the hollow configuration.