Microstructure evolution,mechanical properties and diffusion behaviour of Mg-6Zn-2Gd-0.5Zr alloy during homogenization |
| |
Authors: | Lei Xiao Guangyu Yang Yang Liu Shifeng Luo Wanqi Jie |
| |
Affiliation: | State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China |
| |
Abstract: | The microstructure evolution and mechanical properties of Mg-6Zn-2Gd-0.5Zr alloy during homogenization treatment were investigated. The as-cast alloy was found to be composed of dendritic primary α-Mg matrix, α-Mg + W (Mg3Zn3Gd2) eutectic along grain boundaries, and icosahedral quasicrystalline I (Mg3Zn6Gd) phase within α-Mg matrix. During homogenization process, α-Mg + W (Mg3Zn3Gd2) eutectic and I phase gradually dissolved into α-Mg matrix, while some rod-like rare earth hydrides (GdH2) formed within α-Mg matrix. Both the tensile yield strength and the elongation showed a similar tendency as a function of homogenization temperature and holding time. The optimized homogenization parameter was determined to be 505 °C for 16 h according to the microstructure evolution. Furthermore, the diffusion kinetics equation of the solute elements derived from the Gauss model was established to predict the segregation ratio of Gd element as a function of holding time, which was proved to be effective to evaluate the homogenization effect of the experimental alloy. |
| |
Keywords: | Mg alloy Homogenization Segregation Diffusion kinetics |
本文献已被 ScienceDirect 等数据库收录! |
|