Semi-processed non-oriented silicon steel and manufacturing method thereof

The invention provides semi-processed non-oriented silicon steel. The silicon steel comprises following chemical components by mass: not more than 0.005% and not less than 0 of C, not more than 0.8% and not less than 0.15% of Si, not more than 0.4% and not less than 0.2% of Mn, more than 0.02% and less than 0.1% of P, more than 0% and less than 0.01% of S and not more than 0.1% and not less than 0.03% of Al, with the balance being Fe. The thickness of the silicon steel is 0.35-0.65 mm, the width is 1000-1250 mm, and the surface roughness Ra is 0.4-1.0 [mu]m. Through a plurality of tests and trials, the silicon steel fully meets quality requirements on iron loss and magnetic induction for motors. After secondary annealing and blueing, the performance can be improved by two levels. The silicon steel is favored by users at present. As the development prospect of the motor industry is wide, the silicon steel is high in popularization and application value and has a wide prospect.