Study of microstructural evolution, mechanical properties and plastic deformation behavior of Mg-Gd-Y-Zn-Zr alloy prepared by high-pressure torsion

作者：Xue, Kemin; Luo, Zhicheng; Xia, Shuangwu; Dong, Junfu; Li, Ping^*

来源：Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing , 2024, 891: 145953.

DOI：10.1016/j.msea.2023.145953

• High-pressure torsion
• Magnesium alloy
• Plastic deformation mechanism
• Strengthening mechanism
• Nanograins

The microstructure evolution and mechanical properties of Mg-9Gd-3.8Y-1.9Zn-0.5Zr alloy after high-pressure torsion (HPT) were analyzed. It was found that the dislocation density increased and gradually reached saturation as the number of torsion turns increased. Its microhardness value increases with increasing strain. The microhardness of the alloy was increased to 128 HV after HPT for 15 turns and the grain size was refined from the initial -110 mu m to -63 nm. The strength enhancement mainly originates from fine-grained strengthening, with a contribution of about 42 %. Additional contributions are provided by dislocation strengthening, second phase strengthening, and stacking faults strengthening. The plastic deformation of the material during the HPT process is coordinated by the interaction of multiple slip and {1011} compression deformation twinning.