Effect of manganese and sulfur on the texture and magnetic properties of non-oriented steel

An investigation was made to examine the influence of Mn and S levels up to 0.65 and 0.02 wt%, respectively, on the magnetic properties and texture of non-oriented low carbon steels. The results indicate that at a particular sulfur level, the 15 kG core loss decreases linearly with Mn concentration at an estimated rate of about 2.40 watts/lb/wt% Mn. The reduction in this property is associated with increasing grain size, decreasing eddy current loss and changes in texture. Similarly, a significant improvement in permeability at 15, 17, and 18 kG is generally observed as a function of Mn content, which is explained in terms of texture and microstructure. In addition, it is noted that for a given Mn concentration, these magnetic properties are generally improved by lowering the sulfur level from 0.020 to 0.005 wt%. The improvements in these properties are also discussed in terms of texture, microstructure and the level of inclusion content. The above findings suggest that superior magnetic properties are obtained in non-oriented steels with the addition of higher manganese and lower sulfur levels.