Effect of Deep Cryogenic Treatment and Aging Treatment on Microstructure and Mechanical Properties of Mg-7.5Li-3.5Zn-2Y Alloy Sheet
Author of the article:XU Chunjie;WANG Yidan;HUA Xinyu;REN Guolu;LI Yang;LIU Jun
Author's Workplace：School of Materials Science and Engineering, Xi'an University of Technology, Xi'an 710048, China;Xi'an Shechtman Nobel Prize New Materials Institute, Xi'an 710048, China
Key Words：Mg-Li alloy deep cryogenic treatment (DCT) aging treatment microstructure and properties
Abstract：
Mg-7.5 Li-3.5 Zn-2 Y alloy sheet with 30 mm wide and 1 mm thick was prepared by reciprocating extrusion(RE)and forward extrusion(EX). The microstructure and properties of alloy sheet after aging, deep cryogenic treatment(DCT)and aging + deep cryogenic treatment(DCT) were investigated. The results show that aging and DCT are conducive to promoting the precipitation of the second phase. aging and DCT can significantly improve the comprehensive mechanical properties of Mg-Li alloys. However, the aging temperature and time of the alloy as well as the time of DCT should be controlled. After aging at 200 ℃ for 2 h and DCT at-196 ℃ for 60 h, the alloy sheet has the best comprehensive properties, with tensile strength UTS of 213 MPa and elongation of 20%, which can meet the requirements for comprehensive mechanical properties of materials under large plastic deformation at room temperature.
