Investigation of microstructure and properties of strip-cast 4.5 wt% Si non-oriented electrical steel by different rolling processes

A 4.5 wt% Si as-cast strip with equiaxed grains microstructure fabricated by twin-roll caster was subjected to three different cold rolling and final recrystallization annealing processes. The results revealed that the rolling process has a significant effect on the evolution of microstructure and texture of the strip-cast 4.5 wt% Si non-oriented electrical steel. Moreover, both mechanical and magnetic properties of the steel exhibited various characteristics because of different rolling routes. After short-time annealing at high temperature, the steel sheet experienced one-step cold rolling exhibits the highest tensile strength. Regarding two-step cold rolling, better magnetic properties were obtained after a second cold rolling with a slight reduction. The excellent performance of mechanic and magnetic properties can be fabricated by two-step medium reduction cold rolling.