Bi对Mg-3Al-3Nd合金显微组织和力学性能的影响  

Effect of Bi on Microstructure and Mechanical Properties of Mg-3Al-3Nd Alloy

作　　者：陈亮 王丽萍[1] 冯义成[1] 王雷[1] 赵思聪[1] CHEN Liang;WANG Liping;FENG Yicheng;WANG Lei;ZHAO Sicong(School of Materials Science and Engineering,Harbin University of Science and Technology,Harbin 150040,China)

机构地区：[1]哈尔滨理工大学材料科学与工程学院,哈尔滨150040

出　　处：《材料研究学报》2020年第6期425-433,共9页Chinese Journal of Materials Research

基　　金：国家自然科学基金(51804090);黑龙江省科学基金(E2018045)。

摘　　要：使用扫描电子显微镜(SEM)和光学显微镜(OM)观察、X-射线衍射(XRD)分析以及力学性能测试等手段研究了Bi含量对Mg-3Al-3Nd合金的显微组织和力学性能的影响。结果表明:添加Bi元素可细化Mg-3Al-3Nd合金的组织。当Bi含量(质量分数)为1%时晶粒最小,晶粒尺寸从1854±58μm减小到890±64μm;Mg-3Al-3Nd合金由呈网状分布在晶界的Al11Nd3相和分布在晶内的颗粒状Al2Nd组成;随着Bi含量的提高Al11Nd3相和Al2Nd相的数量减少,晶内的BiNd相数量增加;Bi能明显改善Mg-3Al-3Nd合金室温和高温力学性能,Bi含量为1%时其室温和高温力学性能最佳。室温抗拉强度和延伸率分别为167±2.3 MPa和(16.1±0.3)%,高温抗拉强度及延伸率分别为136±1.7 MPa和(19.3±0.3)%。The effect of Bi on the microstructure and mechanical properties of Mg-3 Al-3 Nd alloy was investigated by scanning electron microscope(SEM), optical microscope(OM), X-ray diffraction(XRD)and tensile test. The results show that the addition of Bi can refine the microstructure of Mg-3 Al-3 Nd alloy. When the content(mass fraction) of Bi is 1% the grain size of Mg-3 Al-3 Nd alloy is the smallest, whilst the grain size reduced from 1854±58 μm for the plain Mg-3 Al-3 Nd alloy to 890±64 μm for the alloy with1% Bi addition. The Mg-3 Al-3 Nd alloy is mainly composed of Al11Nd3 phase distributed at grain boundaries and granular Al2Nd distributed within grains. With the increasing Bi content, the volume fraction of Al11Nd3 phase and Al2Nd phase decrease, and the volume fraction of BiNd phase distributed within grains increases. The mechanical properties of Mg-3 Al-3 Nd alloy at room temperature and high temperature are significantly improved with addition of Bi. The ultimate tensile strength and elongation at break of Mg-3 Al-3 Nd alloy with 1% Bi addition at room temperature and high temperature is 167±2.3 MPa and 16.1±0.3%,136±1.7 MPa and 19.3±0.3%, respectively.

关 键 词：金属材料 镁合金 BI 显微组织 力学性能 

分 类 号：TG113.12[金属学及工艺—物理冶金]