Influence of Guillotine Clearance on Cut-Edge Damage to Nonoriented Electrical Steel

Abstract

Nonoriented electrical steel of 0.65 mm thickness was sheared to investigate the influence of guillotine clearance on cut-edge damage. The result shows that all the burr, work hardening, and magnetic property damage present an increasing trend initially, then a decrease, followed by an increase with increasing guillotine clearance. In particular, when the relative guillotine clearance (c/t) is within 4.6-6.2%, the burr is small and the cut edge is only slightly damaged. Damage to the burr, work hardening, and magnetic properties are influenced and inter-correlated. The plastic deformation of the microstructure at different c/t ratios is the decisive factor affecting burr forms and cut-edge damage. On the one hand, it leads to different degrees of work hardening and then results in a diversity of crack propagation patterns, forming burr and cross-sectional morphologies with different shapes. On the other hand, the stress distribution and grain orientation also change, which further influences the magnetic properties. Moreover, the relationship between microstructure deformation and grain orientation was established by analyzing texture occupancy and orientation distribution function diagrams. It is clarified that both nucleation position evolution and edge stresses generated by different clearances contribute to the evolution of grain orientation and texture.