In the present work, the microstructure and texture of non-oriented 3.3% Si steel processed by asymmetric rolling (ASR) and subsequent annealing at different temperatures were compared with those obtained when using traditional symmetric rolling (SR). This work aims to reveal the effect of shear bands introduced by the ASR on the microstructure and texture evolution. The ASR sample reaches a recrystallization fraction of 62% at an annealing temperature of 650 °C, which is 32% higher than that of the SR sample annealed at the same temperature. This can be attributed to the abundant shear bands introduced by the ASR, which serve as the heterogeneous nucleation sites for the recrystallized grains. When increasing the annealing temperature to 750 °C, complete recrystallization could be observed in both asymmetric- and symmetric-rolled samples. When using an annealing temperature of 650 °C, the γ-oriented grains were dominant in the surface layer, while strong Goss-oriented grains could be observed in the center in the ASR sample. This is due to the fragmented small subgrains with different orientations in the surface layer inhibiting the nucleation of Goss- and cube-oriented grains during the annealing. In contrast, numerous Goss- and cube-oriented grains were formed in the surface layer after complete recrystallization when the ASR sample was annealed at a temperature of 750 °C. This may be related to the higher thermal energy, which benefits the nucleation of the Goss- and cube-oriented grains. In addition, ASR significantly increased the strength of η-fiber after complete recrystallization when compared with SR. This work might be helpful to design the rolling and the subsequent annealing processes.

The classic molecular dynamics (MD) simulation approach has been used to investigate the microstructure change in polycrystalline magnesium (Mg) during compressive deformation at various temperatures. At low temperatures, there exists a competition between the sliding of Shockley partial dislocation (SPD) and perfect dislocation. Abundant dislocation behaviors such as dislocation bundle and double cross slipping are observed. With a temperature increase, the dislocation sliding is hindered by the newly formed grain boundaries (GBs). The grain reorientation should be the compensatory mechanism for plastic deformation at high temperatures. Furthermore, dynamic recrystallization (DRX) is found at the highest temperature investigated. For all the temperature cases studied, twinning is unsensitive against applied compressive stress. The results of this work may help to understand the temperature effect on the mechanism in polycrystalline Mg under compressive deformation.