Handbook of Magnetic Measurements

Magnetic Materials 127

of annealing and of cooling should be precisely con-

trolled. The optimal grain size is around 100–200 μm

(Figure3.27).

In NO SiFe, the presence of impurities is directly

related to the hysteresis loss, which constitutes almost

75% of the total loss. Hence it is a crucial for magnetic

performances is presence of impurities (Figure 3.28).

Therefore, the starting material and technology of

removing carbon (decarburization), oxide, sulfur, and

nitride are very important. In modern NO steel, these

impurities do not exceed 10 ppm. NO SiFe steel is manu-

factured with different contents of silicon ...