Effects of rolling temperature on microstructure, texture, formability and magnetic properties in strip casting Fe-6.5 wt% Si non-oriented electrical steel

Fe-65 wt% Si non oriented electrical steel sheets with a thickness of 0.50 mm were produced by using a new processing route: strip casting followed by hot rolling, intermediate temperature (150-850 degrees C) rolling and final annealing. The present study focused on exploring the effects of rolling temperature varying from 150 to 850 degrees C on the microstructure and texture evolution, the formability and final magnetic properties. The microstructure and texture evolution at the various processing steps were investigated in detail by using OM, XRD, EBSD and TEM. It was found that the formability during rolling, the microsTructure and Texture before and afTer annealing and final magnetic properties highly depended on rolling TernperaLure. The formability during rolling was gradually improved with increasing rolling Temperature due To the slipping of dislocaTion. In parricular, the rolling Temperature dominated the formation of in grain shear bands in the rolled microstructure, which played an important role in the development of final recrystallization rnicrostrucTure and Texture. in The case of lower Temperature (150-450 degrees C) rolling, an inhornogeneous microstrucLure with a large amount of in grain shear bands was formed in the rolled sheers, which finally resulted in a fine and inhomogencous annealing microstructure dominated by mild ? lambda-fiber texture composed of cube and {001}< 210 > components and alpha*-fiber texture concentrated on {115}< 5-10 1 > component. By contrast, in the case of higher temperature (650-850 degrees C) I olling, a relatively homogeneous microstructure without in-grain shear bands was formed instead in the rolled sheets, which finally led to a coarse and relatively homogeneous annealing microstructure characterized by strong alpha-fiber and gamma-fiber texture. Accordingly, on the whole, both the magnetic induction (B-8 and B-50) and iron loss (P-15/50 and P-10/400) decreased with raising rolling temperature. (C) 2015 Elsevier B.V. All rights reserved