Microstructure and properties of WE93 alloy  

WE93合金的组织与性能(英文)

作　　者：何兰强[1] 李永军[1] 李兴刚[1] 马鸣龙[1] 张奎[1] 王献文 鄢建明 林海涛 

机构地区：[1]北京有色金属研究总院有色金属材料制备加工国家重点实验室,北京100088 [2]西南铝业(集团)有限责任公司,重庆401326

出　　处：《Transactions of Nonferrous Metals Society of China》2011年第4期790-794,共5页中国有色金属学报（英文版）

基　　金：Projects(2007CB613704,2007CB613705)supported by the National Basic Research Program of China

摘　　要：The microstructure of WE93 alloy in different states and the mechanical properties at room temperature were investigated, and the creep behavior of the extruded and aged alloy at 200 ℃and at stress of 100, 125 and 150 MPa was also discussed. The result shows that the microstructure of as-cast WE93 alloy consists of α-Mg, Mg 12 （MM） and Mg 24 Y 5 with an average grain size of 45 μm. After being homogenized at 535 ℃for 18 h, the Mg 24 Y 5 phase is dissolved completely and there is only Mg 12 （MM） phase left around the grain boundaries. The grains do not grow up as prolonging the homogenization time. The extruded alloy has better mechanical properties than the as-cast alloy, especially the elongation increases to 12.5%. The extruded and aged alloy exhibits the highest yield strength and ultimate tensile strength of 315 and 385 MPa, respectively, however, the elongation decreases to 6.5%. The extruded and aged alloy exhibits good creep resistance at 200 ℃and at stress of 100 150 MPa. The creep stress exponent n is 2.97, suggesting that grain boundary sliding plays a dominant role at the corresponding temperature and applied stresses.研究不同状态WE93合金的组织与室温力学性能,以及时效态合金在温度200°C,应力100、125和150MPa条件下的蠕变性能。结果表明:WE93合金铸态组织由α-Mg、Mg12(MM)及Mg24Y5相组成,其平均晶粒尺寸为45μm。铸态合金经535°C保温18h均匀化处理后,Mg24Y5相基本完全分解,晶界周围仅残留MM相,晶粒尺寸随着保温时间的延长未见明显长大。挤压态合金较铸态合金具有更好的力学性能,尤其是其延伸率达到12.5%。经过时效处理的挤压态合金的屈服强度及断裂强度最高,分别为315和385MPa,但延伸率降至6.5%。经时效处理后的挤压态合金在200°C,应力100150MPa条件下具有较好的抗蠕变性能,应力指数为2.97,说明在相应的温度及应力条件下晶界滑移为该合金的主要蠕变机制。

关 键 词：rare-earth magnesium alloy mish-metal microstructure temperature STRESS CREEP 

分 类 号：TG136.1[一般工业技术—材料科学与工程]