CGO silicon steel and Hi-B silicon steel also have some differences in the production process: Hi-B steel uses single-stage cold rolling process; CGO silicon steel uses two-stage cold rolling process and added intermediate annealing treatment between the two-stage cold rolling process.
After that, the plate was cold rolled to a thickness of 0.68 mm and finally secondary cold rolled to a thickness of 0.27 mm after intermediate annealing; then, the primary recrystallization annealing was performed.
As shown in Figure 1, the average grain size of CGO silicon steel after primary recrystallization increases with the rising of intermediate annealing temperature.
Therefore, the higher annealing temperature induces coarser grain sizes after intermediate annealing. When the grains of intermediate annealing are larger, more shear bands will be formed in the deformed microstructure after secondary cold rolling.
Influence of Intermediate Annealing Temperature on the Primary Recrystallization Texture Distribution.
The current work investigated the effect of different intermediate annealing temperatures on the primary recrystallization textures under different primary recrystallization annealing temperatures which are 820[degrees]C and 850[degrees]C, respectively.
As presented in Figures 5(a) and 5(b), a higher primary recrystallization annealing temperature can reduce the content of low angle boundaries and increase the content of high angle boundaries at the same intermediate annealing temperature, which is conducive to the abnormal growth of Goss grains during the secondary recrystallization .
(1) CGO silicon steel went through intermediate annealing at 800[degrees]C, 840[degrees]C, and 860[degrees]C; then, primary recrystallization at 820[degrees]C and 850[degrees]C obtained equiaxed ferrite microstructure in the experimental specimens.
(2) The primary recrystallization texture of CGO silicon steel is affected by the intermediate annealing temperature.
(3) The content of high angle boundaries after primary recrystallization is influenced by the intermediate annealing temperature of CGO silicon steel, which is increased at first and then decreased with the rising of intermediate annealing temperature.