Abstract: The effect of cold rolling thickness on microstructure and magnetic properties of  3.0 %  Si non oriented silicon steel was investigated in this paper. The results showed that, when the coldrolling thickness reduced from 0.35 mm to 0.27 mm, the grain size was decreased from 104 μm to 89 μm, and the iron losses of both  P1.5/50 and  P1.0/400 were respectively decreased from 2.186 W/kg to 2.139 W/kg and from 16.978 W/kg to 13.978 W/kg, and the magnetic induction of B50 was decreased from 1.684 T to  1.662 T. Meanwhile, as the decrease of cold rolling thickness, the proportion of eddy current loss was decreased, with the decrease of the texture orientation of {112}〈110〉 and the increase of {111}〈110〉.

Key words: non oriented silicon steel, coldrolling reduction ratio, microstructure,  , texture