熔模精密铸造新型Mg-Zn-Al合金的显微组织及力学性能  

Research on Microstructure and Mechanical Properties of New Mg-Zn-Al Alloy Prepared by Investment Casting

作　　者：肖伟[1,2] 梁松茂[2] 赵忠兴[1] 陈荣石[2] 

机构地区：[1]沈阳理工大学材料科学与工程学院,辽宁沈阳110168 [2]中国科学院金属研究所金属腐蚀与防护国家重点实验室,辽宁沈阳110016

出　　处：《热加工工艺》2011年第5期5-8,共4页Hot Working Technology

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

关 键 词：MG-ZN-AL合金 熔模铸造 显微组织 力学性能 

分 类 号：TG249.5[机械工程—精密仪器及机械]