摘要
采用熔模精密铸造法制备了Mg-9wt%Zn-3wt%Al(简写为ZA93,下同)合金。利用扫描电镜,X-射线衍射(XRD),冷却曲线热分析技术(CA-CCA)研究了ZA93合金的显微组织和凝固路径。同时,研究了熔模铸造ZA93合金在铸态、T4(固溶处理)和T6(固溶+时效处理)状态下的显微组织和力学性能。结果表明,ZA93合金在凝固过程中依次析出α-Mg相、准晶I相和共晶ε-MgZn相,对应温度分别为602、342和332℃;T6处理后,在合金晶内和晶界处析出细小强化相,提高了合金强度。
Mg-9wt%Zn-3wt% Al （ZA93） was prepared by investment casting. The microstructure characterization and the solidification pathway were investigated by SEM, EDS, XRD and computer aided-cooling curve analysis （CA-CCA）. The effects of heat treatment on the microstructure and mechanical properties of ZA93 alloy were also investigated. The results show that quasi-crystalline I-phase and ε-MgZn phase are the main intermetallic phases in ZA93 alloy. During solidification, the solidification sequence of the second phase is α-Mg, quasi-crystalline I-phase and ε-MgZn phase, at 602℃, 342℃ and 332℃, respectively. Solid solution treatment followed by aging treatment （T6 treatment） significantly improves the tensile strength of the alloy due to the precipitation of some free intermetallic particles along the grain boundaries
出处
《热加工工艺》
CSCD
北大核心
2011年第5期5-8,共4页
Hot Working Technology
