连续变通道挤压-剪切工艺对镁合金薄壁管材组织性能的影响  

Effect of Continuous Variable Cross-section Extrusion and Shear(CVCES)on Microstructures and Properties of Magnesium Alloy Thinned-wall Tube

作　　者：张威 胡红军[1] 张慧玲 赵健行 赵辉 张丁非[2] ZHANG Wei;HU Hong-jun;ZHANG Hui-ling;ZHAO Jian-xing;ZHAO Hui;ZHANG Ding-fei(School of Materials Science and Engineering,Chongqing University of Technology,Chongqing 400050,China;School of Materials Science and Engineering,Chongqing University,Chongqing 400044,China)

机构地区：[1]重庆理工大学材料科学与工程学院,重庆400050 [2]重庆大学材料科学与工程学院,重庆400044

出　　处：《精密成形工程》2022年第10期40-48,共9页Journal of Netshape Forming Engineering

基　　金：国家自然基金面上项目(52071042,51771038);重庆英才项目(CQYC202003047);重庆市自然科学基金项目(cstc2018jcyjAX0249,cstc2018jcyjAX0653)。

摘　　要：目的针对高性能镁合金薄壁管材的加工和制备,提出一种新型复合挤压制备工艺,并验证新工艺对于管材性能的影响。方法通过数值模拟结合实验,建立镁合金管材连续变通道挤压-剪切工艺(CVCES)成形三维有限元模型,分析CVCES成形过程中坯料的等效应力和累积应变;对坯料纵截面沿挤压方向上的不同位置进行微观组织观察,对比分析CVCES成形管材与普通成形管材的金相结果;对成形管材进行强度测试对比。结果与普通挤压镁合金管材相比,CVCES成形管材晶粒细化效果更明显,抗拉强度约为320 MPa,硬度高出13%左右。结论CVCES工艺可以有效地细化晶粒,成形管材的平均硬度和抗拉强度明显增大。The work aims to propose a new composite extrusion preparation technique for the fabrication and preparation of high performance magnesium alloy thin-wall tube,and the effect of new process on the tube performance is verified.A three-dimensional finite element model of Continues Variable Cross-section Extrusion and Shear(CVCES)forming was estab-lished through numerical simulation combined with experiments,and the equivalent forces and accumulated strains of the tube dur-ing CVCES forming process were analyzed;the microstructure of the longitudinal section of tube was observed at different posi-tions along the extrusion direction,and the metallographic results of CVCES forming tube and direct extrusion forming tube were compared and analyzed;the strength test and comparison of forming tube were carried out.The results demonstrate that compared with direct extruded magnesium alloy tube,the grain refinement effect of CVCES forming tube is more obvious,the tensile strength is about 320 MPa and the hardness is about 13%higher.The CVCES process can effectively refine the grain,resulting in a significantly higher average hardness and tensile strength of formed tubes.

关 键 词：镁合金管材 复合挤压 晶粒细化 微观组织 

分 类 号：TG376.9[金属学及工艺—金属压力加工]