The effects of recrystallization texture and grain size on magnetic properties of 6.5 wt% Si electrical steel

摘要

Cold rolled sheets of high silicon electrical steel (Fe-6.5 wt% Si alloy) with thicknesses of 0.2-0.4 mm were fabricated by directional solidification and rolling, and the microstructure, texture and magnetic properties of the sheets annealed at 700-1300 ℃ for 1 h were investigated. The roles of recrystallization texture and grain size in influencing the magnetic induction and core loss were clarified. All the samples had strong {100} recrystallization texture with volume fraction of 18.3-47.3% and exhibited high magnetic induction and low core loss. For the samples with a thickness of 0.2 mm after annealing at 800-1200 ℃, the magnetic induction B_8 and the core loss P_(10/50) reached 1.273-1.378 T and 0.49-0.84 W/kg, respectively. The grain size played a much more important role in the core loss than recrystallization texture. The average grain size to seek minimum core loss P_(10/50) was 536-615 μm in the high silicon electrical steel sheets with thicknesses of 0.2-0.4 mm, which was larger than 100-200 μm for the electrical steel with common silicon content. The magnetic induction B_8 of the samples improved with an enhancement of {100} recrystallization texture, but reduced with an increase of average grain size. The effect of recrystallization texture on the magnetic induction B_8 was much greater than that of grain size.