Research on deformation mechanism of AZ31 magnesium alloy sheet with non-basal texture during uniaxial tension at room temperature: A visco-plastic self-consistent analysis

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 < a > slip and prismatic < a > slip, { 10 1 over bar 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 over bar 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 over bar 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 over bar 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 < a > slip and pyramidal < c + a > 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 < a > slip and pyramidal < c + a > slip, the smaller separation is between these two tilted basal poles. Besides, VPSC modeling overestimates volume fractions of { 10 1 over bar 2} ET in samples with angle of 0 to 30 degrees 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 over bar 2} ET in samples with angle of 45 to 90 degrees between loading direction and RD of sheet are smaller than the correspondingly measured results. (c) 2021 Chongqing University. Publishing services provided by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )

Automated summary

The relationship between the activities of different deformation mechanisms and the evolution of microstructure and texture in the uniaxial tension of AZ31 magnesium alloy with a rare non-basal texture was investigated using electron backscattered diffraction (EBSD) measurement and visco-plastic self-consistent (VPSC) modeling. The results showed that both basal and prismatic slip, as well as extension twin, played significant roles in plastic deformation. The activity of the extension twin decreased with the increasing angle between the loading and rolling directions, and its role shifted from sustaining plastic strain to accommodating local strain between grains. The different roles of the extension twin resulted in the formation of different texture components. The competition between basal and pyramidal slip was responsible for the concentration of tilted basal poles towards the normal direction. VPSC modeling overestimated the volume fractions of the extension twin, and the predicted results were smaller when compatible deformation between grains was not considered.