Effects of shearing processing on the quality and magnetic properties of electric steel sheet

Mechanical manufacturing process of electric motor induces a residual stress, which increases the iron loss, and affects the efficiency and performance of machine. In this paper, a shear test was carried out on a non-oriented electrical steel sheet with a thickness of 0.50 mm and a relative clearance range of 2–12% of the thickness, and the shear force was detected during shearing process. The sheared surface morphology, microhardness distribution and magnetic properties after the shearing processing were also tested. The obtained experimental results indicate that: as the shear clearance increases, the shear force increases, the plastic deformation zone enlarges, and the flow of microstructure becomes intense. In addition, as the shear clearance increases, the depth and work-hardening degree of the work-hardened layer increase, resulting in degraded magnetic properties of the electrical steel. Moreover, when the lateral clearance is 5%, a complete and smooth shear section can be obtained.