Effect of Asymmetric Rolling on the Microstructure, Mechanical Properties and Texture Evolution of Mg-8Li-3Al-1Y Alloy

Asymmetric rolling was applied to dual phase Mg-8Li-3Al-1Y alloy with different speed ratio and rolling reduction. With increasing reduction at the same speed ratio the population of beta-Li grains decreased with a feature of fibered grains along the rolling direction. As for different speed ratio under the same reduction, beta-Li grains kept equiaxed, but alpha-Mg phase was first elongated and fibered and then transited to equiaxed small grains. The enhanced yield strength and tensile strength were achieved with the increase of rolling reduction and speed ratio. In particular, when speed ratio reached to 1:1.3 under the same rolling reduction (30%), the optimal mechanical properties were obtained. As for texture evolution, we found the basal texture was obviously weakened and some new weak texture was formed after asymmetric rolling. Interestingly, it was noted that the texture on the side of slow roll is distinct from that on the side of the fast roll due to the different rolling speed.