中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 20 No. 5 May 2010 |
ZA62 based magnesium alloys with calcium addition
（1. School of Materials Science and Engineering, Southeast University, Nanjing 211189, China;
2. Jiangsu Key Laboratory for Advanced Metallic Materials, Nanjing 211189, China;
3. Jiangsu Engineering Research Center For Magnesium Alloys, Nanjing 211224, China）
Abstract:As-cast microstructure and mechanical properties of Mg-6Zn-2Al-0.3Mn (ZA62) alloys with calcium addition were investigated. The as-cast microstructure of the base alloy ZA62 consists of the α-Mg matrix and eutectic phase Mg51Zn20. The Mg51Zn20 eutectic was gradually replaced by MgZn phase and Mg32(Al,Zn)49 phase when calcium is added into the base alloy. Further addition of calcium leads to the increase of grain boundary phases and formation of a new quaternary Mg-Zn-Al-Ca eutectic compound. In comparison with the base alloy, the increase of calcium addition to the base alloy results in the reduction of both strength and ductility at ambient temperature, but increase at elevated temperatures due to the thermal stability of Ca-containing phases. At elevated temperatures, the creep resistance of ZA62 based alloys containing calcium is significantly higher than that of AZ91 which is the most commonly used magnesium alloy.
Key words: magnesium alloys; ZA62 alloys calcium; creep properties
