中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 27 No. 4 April 2017 |
（1. School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China;
2. National Key laboratory for Precision Hot Processing of Metals, Harbin Institute of Technology, Harbin 150001, China;
3. School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhangjiagang 215600, China;
4. Mechanical and Manufacturing Engineering and Design Research Institute, School of Aerospace, RMIT University, GPO Box 2476, Melbourne, VIC 3001, Australia）
Abstract:Minor Dy element was added into a Mg-4Y-3Nd-0.4Zr alloy, and its effects on the microstructure and the mechanical properties at elevated temperatures were investigated. Scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to observe the microstructures. The results indicated that the as-cast eutectic and isolated cuboid-shaped Mg-RE phases were Mg5RE and Mg3RE17, respectively, and distributed mainly along grain boundaries. After a solution treatment, the eutectic Mg5RE phases were dissolved into the matrix, whereas the Mg3RE17 compound still remained. After peak aging, fine Mg-RE phases were precipitated homogeneously within the matrix of the alloys containing Dy. Dy addition can result in a significant improvement in the tensile strength at both room and elevated temperatures, and a slight decrease in the elongation.
Key words: magnesium alloy; Dy addition; microstructure; mechanical property
