(1. 武汉理工大学 材料科学与工程学院, 武汉 430070;
2. 武汉理工大学 机械工程学院, 武汉 430070)
摘 要: 利用光学显微镜、 电子探针和X射线衍射仪研究Nd对AZ91镁合金铸态显微组织的影响， 并利用Imagetool软件测量晶粒尺寸和面积。 结果表明： 少量Nd对α-Mg晶粒有显著的细化作用， 平均晶粒尺寸由108 μm降至约31 μm， 晶粒面积也明显减小， Nd的最佳加入量为0.5%。 此外， Nd的加入致使β-Mg17Al12相弥散细小， 组织中出现了粒状或针状Al3Nd化合物。
关键字: AZ91镁合金； 钕； 显微组织
（ 1. School of Materials Science and Engineering,
Wuhan University of Technology, Wuhan 430070, China;
2. School of Mechanical Engineering, Wuhan University of Technology,
Wuhan 430070, China）
Abstract: Effect of neodymium addition on as-cast microstructure of AZ91 magnesium alloy was studied by optical microscope, electron probe microanalyzer and X-ray diffraction analyzer, the diameter and area of α-Mg grains were measured by image tool. The results show that a small amount of neodymium addition to AZ91 magnesium alloy fines the α-Mg grains, the average grain size becomes 31 μm from 108 μm and the area of grain decreases obviously, the optimum content of Nd is 0.5%. With the addition of Nd, the amount of β-Mg17Al12 phases decrease, and their size becomes dispersed and fine. In addition, the granular and needle-like Al3Nd phases mainly distributed at grain boundaries are observed in the AZ91 alloys containing neodymium.
Key words: AZ91 magnesium alloy; neodymium; microstructure
