摘要
采用等通道转角挤压(ECAP)工艺在573 K温度下以Bc、A和C三种工艺路径对双相Mg-10.73Li-4.49Al-0.52Y镁锂合金分别进行1-4道次挤压变形,利用光学显微镜、扫描电镜和X射线衍射等研究变形后合金组织。结果表明,三种路径ECAP变形后,α相和β相晶粒均得到显著拉长和细化;4道次变形后,路径A获得片状晶粒,路径C获得等轴晶,而路径Bc获得等轴状和条状相间的组织。室温拉伸实验表明,Bc路径4道次后获得良好的综合力学性能,其中延伸率达70%。β相{110}晶面织构显示,随着变形道次增加,三种路径的织构变化存在差异.但均出现织构软化现象,对应的抗拉强度也随之降低,此时织构软化作用大于晶粒细化作用。
The extrusion deformation at 573 K was performed on two-phase Mg-10.73Li-4.49AI- 0.52Y magnesium-lithium alloy processed by equal channel angular pressing（ECAP） from 1 pass to 4 passes through routes Bc,A and C.The pressed microstructures were investigated by using OM,SEM and XRD.The results show that the grains of bothαandβphases are significantly elongated and refined after ECAP deformation with different routes.After 4 passes,flaky grains were obtained for route A, equiaxed grains were gained for route C,and structures alternated with equiaxed and lath-like features were observed for route Bc.The mechanical tensile test at room temperature indicates that route Bc gets good integrated mechanical properties,whose elongation is up to 70%.The texture of {110} crystal plane forβphase reveals that different changes exist among three pressing routes with ECAP passes,but textures of all three routes become softening,therefore the tensile strength decreases correspondingly as the texture softening is more effective than grain refining.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2011年第5期500-508,共9页
Chinese Journal of Materials Research
基金
广州市科技支撑计划2009Z2-D811资助项目~~
