Microstructures and mechanical properties of as-cast Mg-Sm-Zn-Zr alloys with varying Gd contents  

作　　者：Kai Guan Daisuke Egusa Eiji Abe Jinghuai Zhang Xin Qiu Qiang Yang Jian Meng 

机构地区：[1]Department of Materials Science&Engineering,The University of Tokyo,Tokyo 113-8656,Japan [2]Key Laboratory of Superlight Material and Surface Technology,Ministry of Education,College of Material Science and Chemical Engineering,Harbin Engineering University,Harbin 150001,PR China [3]State Key Laboratory of Rare Earth Resource Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,PR China [4]Research Center for Structural Materials,National Institute for Materials Science,Tsukuba 305-0047,Japan

出　　处：《Journal of Magnesium and Alloys》2022年第5期1220-1234,共15页镁合金学报（英文）

基　　金：JSPS KAKENHI for Scientific Research on Innovative Areas“Materials Science of a Mille-feuille Structure(Grant Numbers JP18H05475,JP18H05479)”;the Open Funds of the State Key Laboratory of Rare Earth Resource Utilization(RERU2020012);“Nanotechnology Platform”of the MEXT,Japan;Grant-in-Aid for JSPS Fellows(JP19F19775)。

摘　　要：The effect of Gd content on the microstructure and tensile properties of as-cast Mg-Sm-Zn-Zr alloy has been systematically investigated.In the Mg-3Sm-0.5Zn-0.5Zr alloy, the intermetallic compounds with multiple morphologies are identified as Mg_(3)Sm phase. In addition to Mg_(3)RE phase, Mg_(5)RE phase originated from Gd addition is observed in Gd-modified alloys. It should be noted that the lattice parameters of all the observed intermetallic compounds are significantly reduced by Zn segregation. The segregation behavior of Zn in Mg_(3)Sm phase is inhibited to some extent by Gd addition due to the electronegativity difference between Sm/Gd and Zn elements. In addition, the increased Gd content effectively leads to much more accumulation of solute atoms in front of the liquid-solid interface during solidification, which can prominently promote nucleation in liquid region and then refine grains. The tensile yield stress of the present alloys is thus improved with increasing Gd addition. Finally, Gd-modified alloys exhibit significantly age-hardening effect, which can be mainly attributed to the high-volume fraction and high density nano-scale precipitates.

关 键 词：Magnesium alloys Microstructure characterization Mechanical properties Transmission electron microscopy(TEM) 

分 类 号：TG146.22[一般工业技术—材料科学与工程]