Mg-5Y-3Sm-4Ho-0.5Zr合金组织与力学性能  

Microstructure and mechanical properties of Mg-5Y-3Sm-4Ho-0.5Zr alloy

作　　者：戚尧 李全安[1,2] 陈晓亚 史浩鹏[1] QI Yao;LI Quan-an;CHEN Xiao-ya;SHI Hao-peng(School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang 471023,China;Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal new Materials and Advanced Processing Technology,Luoyang 471023,China)

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471023 [2]有色金属新材料与先进加工技术省部共建协同创新中心,河南洛阳471023

出　　处：《材料热处理学报》2020年第9期97-102,共6页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(51571084,51171059)。

摘　　要：采用光学显微镜、扫描电镜、X射线衍射仪、差示扫描量热仪对Mg-5Y-3Sm-4Ho-0.5Zr合金的物相组成及显微组织进行了研究,并采用电子拉伸实验机和布氏硬度计研究了合金的力学性能。结果表明:Mg-5Y-3Sm-4Ho-0.5Zr合金的铸态组织主要由α-Mg基体和断续分布于晶界的Mg24Y5、Mg24Ho5和Mg41Sm5组成,固溶处理后,大部分稀土元素被固溶进基体中形成过饱和固溶体,经时效处理后,有弥散分布的第二相析出;Mg-5Y-3Sm-4Ho-0.5Zr合金的最佳热处理工艺为525℃固溶12 h,然后225℃时效14 h,此时合金具有最好的综合力学性能,硬度、抗拉强度、屈服强度和伸长率分别为106 HBW、246 MPa、242 MPa和3.33%。Phase composition and microstructure of Mg-5 Y-3 Sm-4 Ho-0.5 Zr alloy were studied by means of optical microscope,scanning electron microscopy,X-ray diffraction and differential scanning calorimeter,and the mechanical properties of the Mg-5 Y-3 Sm-4 Ho-0.5 Zr alloy were studied by electronic tensile tester and Brinell hardness tester.The results show that the as-cast microstructure of the Mg-5 Y-3 Sm-4 Ho-0.5 Zr alloy is mainly composed ofα-Mg matrix and Mg24Y5,Mg24Ho5 and Mg41Sm5 distributed intermittently at the grain boundary.After solid solution treatment,most of the rare earth elements are dissolved into the matrix to form supersaturated solid solution,and after aging treatment,there is dispersion-distributed second phase precipitation.The optimal heat treatment process of the Mg-5 Y-3 Sm-4 Ho-0.5 Zr alloy is solid solution at 525℃for 12 h,then aging at 225℃for 14 h,at this time,the alloy has the best comprehensive mechanical properties,the hardness,tensile strength,yield strength and elongation are 106 HBW,246 MPa,242 MPa and 3.33%,respectively.

关 键 词：Mg-5Y-3Sm-4Ho-0.5Zr合金 热处理 显微组织 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]