Effect of heat treatment on microstructure and mechanical properties of Mg-8Gd-3Y-1.5Zn-0.6Zr alloy

doi:10.13251/j.issn.0254-6051.2022.11.008

Abstract

Abstract: Effect of solid solution and aging treatment on microstructure and mechanical properties of Mg-8Gd-3Y-1.5Zn-0.6Zr alloy was investigated by means of optical microscope (OM), scanning electron microscopy (SEM), X-ray diffractometer (XRD) and universal mechanics tester. The results show that the microstructure of as-cast, solid solution treated and aged Mg-8Gd-3Y-1.5Zn-0.6Zr alloy are composed of α-Mg matrix, Mg₅(Gd, Y, Zn) phase and LPSO structure. After solid solution and aging treatment, the ultimate tensile strength is increased from 187.96 MPa(as-cast) to 241.93 MPa, which is increased by 28.71%, and the elongation is increased from 8.48%(as-cast) to 13.91%, which is increased by 64.03%. The tensile fracture morphologies of the alloy under different heat treatment states are mainly brittle fracture.

Key words: Mg-8Gd-3Y-1.5Zn-0.6Zr alloy, heat treatment, microstructure, mechanical properties

CLC Number:

TG156

Tian Kaikai, Li Quanan, Chen Xiaoya, Mei Wanwan, Chen Peijun, Li Xiangyu, Tan Jinfeng. Effect of heat treatment on microstructure and mechanical properties of Mg-8Gd-3Y-1.5Zn-0.6Zr alloy[J]. Heat Treatment of Metals, 2022, 47(11): 54-58.

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