Experimental Study on the Twin Roll Strip Casting and Warm Rolling Fe-6.5 wt. %Si Steel Sheet

Abstract

An Fe-6.5 wt. % Si steel sheet with a final thickness of 0.30 mm was produced by twin roll strip casting and warm rolling process. The effects of casting, warm rolling and annealing process on microstructure, texture and magnetic properties were investigated with optical microscopy, X-ray diffraction and magnetic measurement. The microstructure evolution during preparation was shown as follows: columnar grain and a small amount of fine grain in center (as casted) elongated grains and a small amount of the shear bands along the rolling direction (as rolled) a relatively uniform recrystallized microstructure (as annealed). The texture evolution during preparation was shown as follows: {001} λ fiber texture (as casted) the significant α fiber texture and the weak, inhomogenous γ fiber texture (as warm rolled) the strong {001} λ fiber texture and weak, inhomogenous γ fiber texture (as annealed). The excellent soft magnetic properties were obtained with a very small P1.0/400 of 10.751 W/kg and a very high B50 up to 1.438 T at optimum annealing condition (1150 °C for 1 h). The research work was useful to develop electrical steel by twin roll continuous casting process.