稀土元素Nd对Mg-Zn-Y合金组织结构和力学性能的影响  

Influence of Rare Earth Metal Nd on Microstructure and Properties of Mg-Zn-Y Alloys

作　　者：白雪[1] 王星明[1] 王志刚[1] 储茂友[1] 张碧田[1] 段华英[1] 韩沧[1] 孙静[1] 赵永成[1] 

机构地区：[1]北京有色金属研究总院稀有金属与冶金材料研究所,北京100088

出　　处：《材料导报》2013年第14期8-12,共5页Materials Reports

基　　金：科研院所技术开发研究专项基金(31001)

摘　　要：通过制备Mg-6Zn-1.5Y-0.8Zr-xNd(x=0、1、2、3、4)系列合金,研究了稀土元素Nd对Mg-6Zn-1.5Y-0.8Zr合金组织结构和力学性能的影响。通过金相显微镜、扫描电镜、EDS、XRD等手段,观察和分析了合金的微观形貌和组织结构,测量了合金抗拉强度、屈服强度和伸长率等力学性能。结果表明:合金中添加稀土元素Nd后晶粒明显细化,随着Nd元素含量的增加,晶粒细化效果更为明显;通过XRD分析可知,添加Nd元素后,合金中并没有出现新的含Nd的物相;扫描电镜和EDS分析表明,合金中加入的Nd置换了部分Y,形成了Mg3(NdY)2Zn3、Mg3-(NdY)Zn6的相结构,Nd元素对Y的置换主要出现在Mg3(NdY)2Zn3结构中,在Mg3(NdY)Zn6相结构中出现较少;力学性能测试结果表明,随着Nd含量增多,合金晶粒细化,细晶强化作用明显,合金屈服强度逐渐增大,而抗拉强度和伸长率在Nd含量为3%(质量分数)时达到最大,比未添加Nd元素时提高约25%以上。The Mg-6Zn-1.5Y-0. 8Zr-xNd（x= 0, 1,2,3,4） series alloys were prepared, the influence of rare earth metal Nd on microstructure and properties of Mg-6Zn-1.5Y-0. 8Zr alloys were investigated. The morphology and microstructure of the alloy were researched through microscope, SEM, EDS and XRD methods. The mechanical pro- perties such as ultimate tensile strength（UTS）, yield strength（YS） and elongation（EL） were measured. The results showed that Nd can refine as-cast microstructure of Mg-Zn-Y alloy and refinement effect was more apparent when the content of Nd increased. The phase contains Nd was not found during XRD analysis and it was found that some Y were replaced by Nd and recreated new phase structure like Mg3 （NdY）2 Zna and Mg3 （NdY）Zn6 in the alloy. Nd has replaced Y mainly in Mga （NdY）zZna phase structure and rarely existed in Mga （NdY）Zns phase structure. The results of mechanic property test showed that because of the grain has refined, which caused refinement effect, the YS of the alloy increased slowly as the content of Nd increasing. The UTS and EL both reached the maximum value when the content of Nd was 3wt%, which has increased about 25% compared to the alloy which has none samarium.

关 键 词：MG-ZN-Y合金 稀土元素Nd 微观组织 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程] TG146.4[金属学及工艺—金属材料]