Effect of Hot Rolling Coiling Temperature on Microstructure, Texture, and Magnetic Properties of 1.5 wt.%Si Non-oriented Electrical Steel
摘要
In order to produce 1.5 wt.% Si steel without normalizing process, the effect of coil temperature on the microstructure evolution of non-oriented electrical steel was studied systematically. The results showed that as the coiling temperature increased from 660 to 740 °C, the deformed structure gradually disappeared, and the hot-rolled structure gradually became uniform. The number of λ-oriented grains in the hot-rolled plate increased, while the number of α-oriented grains and γ-oriented grains decreased. As the coiling temperature increases, the deformation band in the cold-rolled plate gradually decreases, the shear band gradually increases, the strength of the α and γ textures weakens, and the λ texture strengthens. With the increase in coiling temperature, the average grain size of the annealed plate increased from 38.6 to 87.3 μm, and the γ-oriented grains gradually decreased while the λ-oriented grains increased, effectively reducing unfavorable texture components and increasing favorable texture components. The magnetic induction B50 increased from 1.682 to 1.694 T, and the iron loss P15/50 decreased from 2.86 to 2.65 W/kg. The annealed plate, after being coiled at 740 °C, exhibits excellent magnetic properties through continuous rolling and recrystallization annealing. The 1.5 wt.%Si non-oriented electrical steel produced by this process is beneficial for improving motor efficiency, thereby reducing costs, increasing efficiency, saving energy, and reducing emissions. It also provides a strategic direction with broad development prospects for the development of non-oriented electrical steel.