Dependence on peak induction and grain size of power losses in nonoriented SiFe steels

We report loss separation measurements performed on 1.8% SiFe nonoriented 0.2‐mm laminations of variable grain size 20 μm≤s≤130 μm, in the frequency range 1 Hz≤ f≤300 Hz and peak induction range 0.7 T≤B≤1.5 T. It is shown that the excess loss behavior is well reproduced by the equation Pe =k(Bf)3/2, in agreement with a theory recently proposed by one of the authors, and the microstructural interpretation of the parameter k is discussed. The results obtained suggest that a systematic investigation of the properties of k may represent a new, promising approach to the characterization of microstructure and texture properties of nonoriented electrical steels.