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The relationship between activities of involved deformation mechanisms and the evolution of microstructure and texture during uniaxial tension of AZ31 magnesium alloy with a rare non-basal texture has been thoroughly investigated in the present study by means of electron backscattered diffraction (EBSD) measurement and visco-plastic self-consistent (VPSC) modeling. These results show that except basal slip and prismatic slip, { 10 1 ¯ 2 } extension twin (ET) also plays a significant role during plastic deformation. With the increasing tilted angle between loading direction and rolling direction (RD) of sheet, the activity of { 10 1 ¯ 2 } ET possesses a decreasing tendency and its role in plastic deformation changes from the one mainly sustaining plastic strain to the one mainly accommodating local strain between individual grains. When { 10 1 ¯ 2 } ET serves as a carrier of plastic strain, it mainly results in the formation of basal texture component (c-axis//ND, normal direction). By comparison, when the role of { 10 1 ¯ 2 } ET is to accommodate local strain, it mainly brings about the formation of prismatic texture component (c-axis//TD, transverse direction). At large plastic deformation, the competition between basal slip and pyramidal slip is responsible for the concentration of tilted basal poles towards ND within all deformed samples. The larger difference is between the activities of basal slip and pyramidal slip, the smaller separation is between these two tilted basal poles. Besides, VPSC modeling overestimates volume fractions of { 10 1 ¯ 2 } ET in samples with angle of 0 to 30° between loading direction and RD of sheet because interactions between twin variants are not included in VPSC modeling procedure at the present form. In addition, as compatible deformation between individual grains cannot be considered in VPSC modeling, the predicted volume fractions of { 10 1 ¯ 2 } ET in samples with angle of 45 to 90° between loading direction and RD of sheet are smaller than the correspondingly measured results.

A novel and efficient deformation methodology, viz., hot-rolling–shearing–bending (HRSB), to introduce a large amount of $$\{ 10\bar {1}2\}$$ extension twins (ETs) and control the texture of the AZ31 magnesium alloy thin sheet was proposed. Microstructure and texture within various regions of the thin sheet fabricated by the HRSB method were investigated by means of electron back-scattered diffraction measurement. The experimental results indicated that using only single pass of HRSB, grains with c-axis//normal direction (ND) in as-received sheet are nearly twinned totally (about 91% volume fraction of $$\{ 10\bar {1}2\}$$ ET), leading to the formation of c-axis//rolling direction (RD) texture component and the disappearance of c-axis//ND texture component. As for the HRS sample which has suffered from rolling–shearing deformation, both a tensile stress component deriving from the shearing deformation and a compressive stress component resulting from the impediment effect of the mould structure are beneficial to activate $$\{ 10\bar {1}2\}$$ ET, the volume fraction of which is about 72%. With respect to the HRSB sample which has undergone rolling–shearing–bending deformation, the further increase in volume fraction of $$\{ 10\bar {1}2\}$$ ET might be mainly related to the resultant compressive stress of the tensile stress derived from the bending deformation and the compressive stress resulting from the impediment effect of mould structure. It would hinder the activation of $$\{ 10\bar {1}2\}$$ ET within twinned areas and promote the migration of existing boundaries of $$\{ 10\bar {1}2\}$$ ET into un-twinned areas.