Effect of boron content on the microstructure and magnetic properties of non-oriented electrical steels

Abstract

The effects of boron content in the range of 0–0.0082 wt%, on the inclusion type, microstructure, texture and magnetic properties of non-oriented electrical steels have been studied. After final annealing, the addition of excess boron(w(Bt)〉0.004 1 wt%) led to the formation of Fe₂B particles. As boron content increased, grain size increased and reached a maximum in steel with 0.004 1 wt% boron. Furthermore, steel containing 0.004 1 wt% boron had the strongest {100} fiber texture, Goss texture and the weakest {111} fiber texture among the five tested steels. Flux density firstly rapidly increased and then suddenly decreased with increasing boron content and reached a maximum in steel with 0.004 1 wt% boron. Conversely, core loss first sharply decreased and then abruptly increased with the increase of boron content and reached a minimum in steel containing 0.004 1 wt% boron. Steel containing 0.004 1 wt% boron obtained the best magnetic properties, predominantly through the development of optimum grain size and favorable texture.

Keywords

boron / non-oriented electrical steel / grain size / texture / magnetic property

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