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Deformation behavior and texture evolution of an extruded Mg 3Li sheet with a weak transverse direction (TD)-split texture during tension along different directions were systematically examined. Prismatic 〈a〉 slip was the dominant deformation mode along the extrusion direction (ED), while basal 〈a〉 slip and {10−12} twinning played key roles at the initial stage of deformation and prismatic 〈a〉 slip was also activated at the middle stage of deformation along the TD. The activation of prismatic 〈a〉 slip contributed to the enhanced 〈10−10〉 // ED component along the ED. However, the {10−12} twinning and basal 〈a〉 slip led to the formation of a new ED-texture component and a gradual rotation of c-axes towards the normal direction (ND) along the TD, respectively. Additionally, the cooperative activation of the {10−12} twinning and prismatic 〈a〉 slip were responsible for the decreased 〈10−10〉 // ED component along the TD. Unlabelled Image • Extruded Mg 3Li sheet exhibited a weak TD-split texture. • The room-temperature deformation modes of Mg 3Li sheet were investigated. • Prismatic 〈a〉 slip played a dominant role during tension along the ED. • Li additions improved the activation of prismatic 〈a〉 slip, under a lower strain. [ABSTRACT FROM AUTHOR]

A remarkable yield asymmetry at room temperature (RT), all the time, severely influenced the wide industrial applications of Mg alloys. Here, we report a novel approach entitled as bimetal casting-co-extrusion to reduce the yield asymmetry of Mg–3Al–1Zn (wt.%) alloy. The results show that when casting temperature is set as 760 °C, Mg–3Al–1Zn/Mg–1Y (AZ31/W1, wt.%) alloy with the sleeve-core structure can achieve a well metallurgical bonding. While casting temperature is below 760 °C, the contact surface of AZ31 and W1 billets takes place massive cracks, and even two alloys are unable to well connect. After co-extrusion, the interface zone of AZ31/W1 rod never has any cracks and holes. By TEM observation, the interface zone of ~ 1 μm is composed of only α-Mg. With increasing the proportion of W1 core, the tensile and compressive elongation-to-failure values of AZ31/W1 rod apparently enhance, and the decrease in tensile strength and the consistence in compressive strength give rise to the improved yield asymmetry from 0.57 to 0.84 at RT. This is mainly attributed to the more activity of slip deformation in tension and the restriction of {10 1 ‾ 2 } extension twinning in compression. Therefore, this work offers an insightful opinion to improve the mechanical properties of Mg alloys, especially the yield asymmetry, by bimetal casting-co-extrusion method. [ABSTRACT FROM AUTHOR]