Effects of Zn on Microstructure and Mechanical Properties of As-cast Mg-Y-Nd-Zr Alloys
SU Zai-jun1,2, YANG Shu-zhong2, LIU Chu-ming2, YANG Xin-hua2, LIU Xian-lan3
1 Department of Mechanical and Energy Engineering, Shaoyang University, Shaoyang 422000, Hunan, China;
2 School of Materials Science and Engineering, Central South University, Changsha 410083, China;
3 Department of Mechanical Engineering, Hunan Institute of Technology, Hengyang 421002, Hunan, China
Abstract：Effects of Zn on microstructure and mechanical properties of Mg-Y-Nd-Zr as-cast alloys were investigated by the optical microscopy(OM), scanning electron microscopy(SEM), X-ray diffractometry(XRD) and the mechanical properties test. The results show that the grain size of Mg-Y-Nd-Zr-xZn(x=0.0%, 0.5%, 1.0%, 1.5%,mass fraction)alloys is greatly refined with the increase of Zn content, which is refined from (57±0.8)μm to (30±0.3)μm. The volume fraction of eutectic structure at grain boundary increases gradually. Mg12Nd phase and Mg24Y5 phase exist mainly in Mg-Y-Nd-Zr as-cast alloy. With the addition of 0.5%Zn, Mg12YZn phase appears at the grain boundary. With the increase of Zn, the volume fraction of Mg12YZn phase and the mechanical properties of the alloys increases gradually. The alloy containing 1.0%Zn exhibits the optimal mechanical properties, the ultimate tensile strength, yield strength and elongation are (208±5.9), (159±3.9)MPa and (7.5±0.2)%, respectively; comparing with the alloy without the addition of Zn, the ultimate tensile strength, yield strength and elongation increase by 18, 42MPa and 1.2%.
苏再军, 杨树忠, 刘楚明, 杨新华, 刘先兰. Zn对铸态Mg-Y-Nd-Zr合金组织和力学性能的影响[J]. 材料工程, 2017, 45(9): 116-122.
SU Zai-jun, YANG Shu-zhong, LIU Chu-ming, YANG Xin-hua, LIU Xian-lan. Effects of Zn on Microstructure and Mechanical Properties of As-cast Mg-Y-Nd-Zr Alloys. Journal of Materials Engineering, 2017, 45(9): 116-122.
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