Effect of rolling process on magnetic properties of Fe-3.3 wt% Si non-oriented electrical steel

In this study, the influence of the rolling process on magnetic properties of Fe-3.3 wt% Si non-oriented electrical steel was investigated. The strip samples were cast using a high solidification cooling rate vacuum sampling method to simulate the solidification conditions of the industrial twin roll thin strip casting (TRSC) process. As-cast samples were subjected to various thermo-mechanical processing routes with different levels of hot-rolling (HR) and cold-rolling (CR). The influence of carbon and sulfur (C&S) contents in the steel were also investigated. Core loss (P-1.5/50, P-1.5/60, P-1.0/50, P-1.0/60) and magnetic induction (B-25, B-50) of the final annealed strip samples were measured to investigate how the magnetic properties are influenced by the final grain-size and texture. It was observed that increased HR deformation increased average final grain size after processing. This larger grain size resulted in lower core loss and higher magnetic induction. For the same level of HR deformation, low C&S steel compositions had exhibited a larger average grain size after the recrystallization annealing than high C&S steels. Using texture measurements, it was observed that the intensity of Goss orientation decreased with an increase in HR deformation.