镁合金反复镦挤变形的有限元分析和实验研究  

Finite element analysis and experimental study on repeated upsetting and extrusion deformation of magnesium alloy

作　　者：范宇田 卢立伟 刘剑波[1,2] 李旻昊 车波 钟银花 刘龙飞 黄伟颖 FAN Yu-tian;LU Li-wei;LIU Jian-bo;LI Min-hao;CHE Bo;ZHONG Yin-hua;LIU Long-fei;HUANG Wei-ying(College of Materials Science and Engineering,Hunan University of Science and Technology,Xiangtan 411201,China;Hunan Provincial Overseas-wisdom Innovation Center of New Energy Vehicle in Industrial-Academic-Research Cooperation,Hunan University of Science and Technology,Xiangtan 411201,China;College of Mechanical and Electrical Engineering,Hunan University of Science and Technology,Xiangtan 411201,China;School of Elevator Engineering,Hunan Electrical College of Technology,Xiangtan 411100,China;School of Energy and Power Engineering,Changsha University of Science&Technology,Changsha 410114,China)

机构地区：[1]湖南科技大学材料科学与工程学院,湖南湘潭411201 [2]湖南科技大学湖南省新能源汽车产学研海智创新中心,湖南湘潭411201 [3]湖南科技大学机电工程学院,湖南湘潭411201 [4]湖南电气职业技术学院电梯工程学院,湖南湘潭411100 [5]长沙理工大学能源与动力工程学院,湖南长沙410114

出　　处：《塑性工程学报》2022年第8期56-65,共10页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(52174362&51975207);湖南省自然科学基金优秀青年基金资助项目(2019JJ30010);湖南省自然科学基金资助项目(2021JJ30257,2020JJ5181,2020JJ6011);湖南省教育厅基金资助项目(19C0773)。

摘　　要：为了改善镁合金的组织和性能,提出一种新型的反复镦挤变形方法,设计了一套集剪切变形和反复镦挤变形于一体的多道次挤压模具。利用DEFORM-3D软件、金相显微镜和维氏硬度计分析了镁合金在反复镦挤变形中的应变、流速和应力的变化,并研究了微观组织均匀性以及硬度分布。结果表明,3道次镦挤变形后,等效应变不均匀指数变得很小,沿样品挤压方向(L1)和横向(L2)的等效不均匀指数最小分别为0.015和0.068,等效应变和等效应力分布均匀,晶粒尺寸从300μm细化到14.6μm,显微组织明显均匀细化,硬度在L1和L2上分别提高了27.1%和20.6%,且分布均匀。To improve the microstructure and properties of magnesium alloy,a new type of repeated upsetting and extrusion deformation method was supposed.A set of multi-pass extrusion die with integrating shear deformation and repeated upsetting and extrusion deformation was designed.The change of strain,flow velocity and stress in repeated upsetting and extrusion deformation process were analyzed using DEFORM-3D software,metallographic microscope and hardness tester,and the microstructure uniformity and hardness distribution were studied.The results show that after three passes upsetting and extrusion deformation,the equivalent strain inhomogeneity index is small.The minimum equivalent inhomogeneity index along the extrusion direction(L1)and transverse direction(L2)of the samples is 0.015 and 0.068,respectively,and the equivalent strain distribution and equivalent stress distribution are uniform.The grain size is refined from 300μm to 14.6μm,and the microstructure is oviously uniform and refined.Hardness in L1 and L2 directions is increased by 27.1%and 20.6%,respectively,and evenly distributed.

关 键 词：AZ31镁合金 反复镦挤变形 有限元模拟 均匀性分析 

分 类 号：TG146.2[一般工业技术—材料科学与工程]