New SMC Materials for Small Electrical Machine With Very Good Mechanical Properties

A new technology may be proposed for the realization of the magnetic parts of electromechanical devices, mainly for small electric machines. Such a technology provides the substitution of the traditional magnetic sheets with parts obtained by molding special magnetic powders [soft magnetic composites (SMC)]. The advantages may be constituted not only by economical reasons, but mostly by the possibility to realize parts having shapes otherwise impossible with the traditional lamination. Some commercial products are available in the market as “ready to press” powders, but their mechanical properties are in general not sufficient. To investigate the possibility to obtain good mechanical properties maintaining the magnetic characteristics of a selected commercial insulated iron powder compound, the authors have conducted a research activity based on the use of special iron powders and a selected epoxy resin as binder. The paper describes the activity carried out for the realization of SMC by mixing iron powders and Epoxy resin with different binder percentages and molding pressures. The obtained results have to be considered very satisfactory and suggest to continue the research argument to explore the possibilities of further improvements.