薄带连铸取向硅钢的热轧孪生行为.

In strip casting grain-oriented silicon steels, the inheritance of coarse λ grains (〈100〉//ND, normal direction) can deteriorate their magnetic properties. To solve the problem, twinning behaviors in strip casting grain-oriented silicon steels during hot rolling were investigated in this work. It is found that after rolling at 650℃, a number of 112〈111〉deformation twins are formed in the coarse solidification microstructure of the steels, in contrast to the well-accepted view that it is difficult to trigger twinning at relatively high temperature in the grain-oriented silicon steels with high stacking-fault energy. The results indicate that the complex stress state during hot rolling may weaken the orientation dependence of deformation twinning. Due to higher stored energy, the intersections of twin/twin boundaries and twin/grain boundaries can act as the preferential nucleation sites for the recrystallized grains during normalizing annealing, leading to a significant increase of recrystallization rate. Because of the restriction from local strain partitioning and the limited size between the twins, the shape of new-formed recrystallized grains is mainly plate-shaped. Consequently, the fine grains with scattered orientations are formed in the normalized microstructure and the coarse λ grains in the solidification microstructure are eliminated. [ABSTRACT FROM AUTHOR]