Non-oriented magnetic steel sheet having low iron loss and high magnetic flux density and manufacturing method therefor

摘要

Non-oriented magnetic steel sheets, which are mainly used as materials for iron cores for use in electric apparatuses, have a low iron loss and a high magnetic flux density at the same time. The non-oriented magnetic steel sheet comprises from 1.5 to 8.0 weight% Si, from 0.005 to 2.50 weight% Mn, and not more than 50 ppm each of C, S, N, O, and B, in which a crystal orientation parameter &lang& GAMMA &rang& is 0.200 or less. In addition, the average crystal grain diameter is preferably from 50 to 500 mu m, and an areal ratio of crystal grains on a surface of the steel sheet is preferably 20% and less, in which crystal plane orientations of the crystal grains are within 15 DEG from the &lang&111&rang& axis. In addition, the non-oriented magnetic steel sheet preferably contains small amounts of elements such as Al, Sb, Ni, Sn, Cu, P, and Cr. The manufacturing method for the non-oriented magnetic steel is also described.