Effects of Rolling Reductions on Microstructure Evolution and Mechanical Properties of Mg–8Li–1Al–0.6Y–0.6Ce Alloy

Abstract

The effects of rolling reductions on microstructure evolution and mechanical properties of as‐rolled Mg–8Li–1Al–0.6Y–0.6Ce alloys are studied. When the thickness reduction increases from 30% to 90%, α‐Mg phase is elongated along the rolling direction, and the aspect ratio of fiber structure increases. At the same time, the volume fraction of β‐Li phase increases, because part of α‐Mg phase transforms into β‐Li phase. When the rolling reduction is 70%, the alloy shows the best comprehensive performance with the ultimate tensile strength (UTS) of 238 MPa and the elongation of 24%, mainly caused by fine‐grain strengthening and strain hardening. During the rolling process, β‐Li phase is deformed preferentially and subsequently drives the deformation of α‐Mg phase. Then some twins are generated, which promote the dislocation slip, thereby promoting the deformation coordination.

Effect of I-Phase on Microstructure and Corrosion Resistance of Mg-8.5Li-6.5Zn-1.2Y Alloy

“…The Mg-Li alloy, due to its light weight, high specific strength, effective electromagnetic shielding, and excellent damping performance, is considered to be one of the most advanced materials with broad opportunities for application in fields such as aerospace, weapons, and electrical apparatuses [1][2][3][4][5]. As far as the Mg-Li alloy is concerned, the crystal structure changes with the addition of a Li element [6][7][8]. When the content of Li does not exceed 5.7 wt.%, the alloy is completely composed of the α-Mg phase with the hexagonal close-packed (HCP) structure; when Li content is in the range of 5.7 to 10.3 wt.%, the alloy is composed of the α-Mg phase and the body-centered cubic (BCC) structured β-Li phase; when the Li content exceeds 10.3 wt.%, the alloy consists of the β-Li phase [9][10][11].…”