Effect of Heat Treatment Process on Microstructure and Texture of Hot-Rolled Sheet of High-Silicon Steel

The influences of heat treatment process (annealing temperature and cooling methods) on the microstructure and mechanic properties of 6.5 wt%Si steel for hot-rolled sheet products were studied by optical microscopy (OM), electron backscattered diffraction (EBSD), and microhardness tester. The results show that when the annealing temperature increases, the average grain sizes become very large similar to abnormal grain growth, but the effects of cooling methods are relatively small. The {001}〈110〉 and {112}〈110〉 textures weakened and {111}〈112〉 texture enhanced with the increase of annealing temperature. γ fiber texture is relatively high. The microhardness strengthens with increasing annealing temperature or decreasing cooling rate, which means that the plasticity weakens. Therefore, annealing temperature and cooling methods were believed to be mainly responsible for the improvement of plasticity, which may have a significant effect on the production of high-silicon steel.