A new approach in the implementation of insulating layers in soft magnetic composite materials

Abstract

Soft Magnetic Composite (SMC) materials show a high potential for growth in the electrification of several industrial sectors for two main reasons: the reduced eddy current losses and the 3D magnetic path which allows to redesign magnetic circuits without geometrical constraints. On the other hand, some material limitations and process restrictions limit the use of SMC on a large scale; this contribution aims to overcome such constraints through a novel surface approach using a Layer-by-Layer (LbL) technique that allows to coat each particle with a nanostructured layer, providing electrical insulation enhanced mechanical strength and withstanding higher treatment temperatures. Four SMCs encompassing the developed innovative multi-functional layers have been prepared and deeply analyzed with a characterization campaign through the study of the surface morphology with a Scanning Electron Microscope (SEM), the magnetic properties with a Single Sheet Tester (SST) and the mechanical strength through the “Transverse Rupture Strength” (or TRS) test. The discussion on the results has to be considered a starting point for future investigations, as each of the four different systems represents a partial solution to a specific SMC problem. Also, some considerations on the possible application are proposed.