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In this study, quasi-in-situ electron backscatter diffraction was employed to investigate the microstructural evolution and deformation behaviour of ZK60 magnesium alloy with an initial 45° extruded state orientation under two high-speed impacts. The experimental results demonstrated that the deformation of the alloy mainly depended on slip and { 10 1 ¯ 2 } tension twinning. With the increase of deformation, the { 10 1 ¯ 2 } tension twins nucleated continuously, and there were stretching twin variants that were 60° away from the original stretching twins. In addition, compared with the conventional orientation (extrusion direction), 45° samples were easier to activate various slips under high-strain rate deformation conditions, especially ⟨c + a⟩ slips. [ABSTRACT FROM AUTHOR]

The Mg–6Zn–xCe–0.6Zr (x = 1, 2) alloys were subjected to a dynamic compression experiment, and the change in microstructure was noticed and studied. The primary components of two alloys are α-Mg matrix, Mg7Zn3 phase, and (Mg1−xZnx)11Ce phase. The two alloys have grain diameters of 2.8 and 3.2 μm, respectively. The dynamic compressive mechanical characteristics of the two alloys show a positive strain-strengthening effect, with Mg–6Zn–1Ce–0.6Zr alloy having somewhat higher values than Mg–6Zn–2Ce–0.6Zr alloy. At a strain rate of 500 s−1, {10 1 ¯ 2} tensile twin is the dominant deformation mechanism for two alloys, but the Mg–6Zn–2Ce–0.6Zr alloy is more prone to produce {10 1 ¯ 2} tensile twin. With the increase of the strain rate, the dominant deformation mechanism changes from {10 1 ¯ 2} tensile twin to pyramidal slip. [ABSTRACT FROM AUTHOR]

This article investigates the correlation between {10 1 ¯ 2} tensile twins and loading paths in extruded AZ31 magnesium alloy. By compressing along the extruded direction (ED) (perpendicular to the grain c-axis direction) and tension along the extruded radial direction (ERD) (parallel to the grain c-axis direction) to generate {10 1 ¯ 2} tensile twins. Observing the evolution of twins characteristics in two loading paths, and each path was chosen on three strains to detect by the electron backscatter diffraction (EBSD) technology. The results show that by compressing along ED, there is significant better mechanical properties, but has better ductility in tension along ERD. The feature of twins number, twins area, twins nucleation and growth preferences within the sample are disparity. The process of {10 1 ¯ 2} twins nucleation and growth during tension, which was shown that twins tend to nucleate at low orientation angle grain boundaries and grow towards them. The number and area of twins are related to the effective interaction area between the force axis and the grain during loading, resulting in a ratio of 4:1 difference in the twins area inside the tensile sample compared to the same strain under compression conditions. [ABSTRACT FROM AUTHOR]