Coordinate regulation mechanism of primary recrystallization texture and microstructure of grain-oriented silicon steel

Abstract

Texture control, which is affected by composition, hot rolling, cold rolling, and annealing, is the core element to improve the magnetic properties of grain-oriented silicon steel and is one of the key scientific problems in developing electrical steel technology. The research and control of first factors have been very mature, and the integrated regulation of upstream and downstream processes has become a breakthrough point for improving texture. For the common grain-oriented silicon steel based on the “two-stage cold rolling method”, primary recrystallization is the stage achievement of smelting, hot rolling, first cold rolling, and decarburization annealing. The grain size and texture characteristics of the primary recrystallization are the only standards to measure the pre-process technology and is the pointer of whether the secondary recrystallization can occur in the subsequent process or not, which are extremely important to improve the magnetic properties. This paper studied the hot rolling, the first cold rolling and decarburization annealing of grain-oriented silicon steel by using XRD, EBSD technologies. The results showed that the hot rolled plate is not as thinner as better, only the optimum ratio of the thickness of hot rolled plate and the first cold reduction rate can obtain optimal primary recrystallization. The minimum iron loss value and maximum magnetic induction intensity are obtained under the primary cold rolling reduction rate controlled at 77.27%, the average grain size of the primary recrystallization is 14 µm, the iron loss P1.7/50 is reduced to 1.02 W/Kg, and the magnetic induction intensity B8 can reach 1.910 T.