Texture and magnetic property evolution of non-oriented Fe–Si steel due to mechanical cutting

Abstract

Microstructures and textures as well as magnetic properties of a non-oriented Fe–Si steel with thickness of 0.5mm and medium silicon content after mechanical cutting were investigated. The results from electron backscatter diffraction (EBSD) analysis indicated that in the cut edge zone, mechanical cutting resulted in a significant increase in low-angle boundaries (LAGBs, 2°≤θ≤15°) and dislocation densities from both the upper surface (in the shear zone) and the lower surface (in the fracture zone). Mechanical cutting also led to a visible change in textures, such as, intensity decrease of λ fiber (<001>∥normal direction [ND]) and γ fiber (<111>∥ND) components from the upper surface as well as Goss texture ({110}<001>texture) from the lower surface. Microstructure and texture changes from the upper surface seem to be more obvious than these from the lower surface. The results from single sheet testing showed mechanical cutting induced an evident deterioration in magnetic properties and a clear change in hysteresis loop of the steel, and these variations became more obvious with increasing cutting length per mass from 0.86m/kg to 2.57m/kg. The largest increment of iron loss reached to 18.45% and 21.76% when the flux density was at 1.0T and 1.5T, respectively. The possible main reasons for the changes in magnetic properties and hysteresis loops were discussed in terms of the texture factor TF or residual stress.