循环扩挤工艺挤压AZ80镁合金的微观组织与力学性能  

Microstructure and mechanical properties of AZ80 magnesium alloy processed by cyclic expansion-extrusion technique

作　　者：薛勇[1] 吴耀金 杨治辉[2] 张治民[1] 齐红娜[1] XUE Yong;WU Yao-jin;YANG Zhi-hui;ZHANG Zhi-min;QI Hong-na(School of Materials Science&Engineering,North University of China,Taiyuan 030051,China;School of Mechanical and Electrical Engineering,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学材料科学与工程学院,山西太原030051 [2]中北大学机电工程学院,山西太原030051

出　　处：《塑性工程学报》2017年第3期57-61,127,共6页Journal of Plasticity Engineering

基　　金：山西省自然科学基金资助项目(2013011022-5)

摘　　要：采用循环扩挤(cyclic expansion-extrusion,CEE)变形工艺挤压AZ80镁合金并借助金相组织观察、拉伸性能测试和EBSD研究了多道次挤压对该合金的组织与性能影响。结果表明:AZ80镁合金经过CEE变形后,晶粒的尺寸随着挤压道次的增加而减小,4道次挤压后,晶粒尺寸细化至2μm,整体分布均匀且呈等轴晶,但是晶粒的细化程度并不是一直随挤压道次的增加而提高,2道次挤压后,随着挤压道次的增加,晶粒的细化程度减慢;镁合金CEE变形后的抗拉强度、屈服强度和伸长率均随挤压道次的增加而不断提高;CEE变形的细化机制是连续动态再结晶。The cyclic expansion-extrusion （CEE） process was conducted on AZS0 magnesium alloy. The effect of multi-pass extrusion on microstructure and properties of the alloy was investigated by means of microstructure observation, tensile test and electron back-scattered diffraction （EBSD）. The results show that, after CEE deformation of AZS0 magnesium alloy, the grain size decreases with the increase of extrusion pass, and after four-pass extrusion, the grain size refines to 2 μm and the distribution of the equiaxed grains is uniform ; howev- er, the degree of the grain refinement does not always increase with the increase of extrusion passes, and after two passes, the degree of the grain refinement decreases slowly with the increase of passes. The tensile strength, yield strength and elongation of the CEE magnesi- um alloy increase with the increase of extrusion passes. The mechanism of the CEE deformation is continuous dynamic recrystallization.

关 键 词：AZ80镁合金 循环扩挤 微观组织 力学性能 

分 类 号：TG376.2[金属学及工艺—金属压力加工]