Al/Cu约束下AZ31镁合金的压缩变形行为  

Compression Deformation Behavior of AZ31 Magnesium Alloy under Al/Cu Constraints

作　　者：刘聪 马立峰[1] 贾伟涛 雷军义 乐启炽[2] 袁媛 潘虎成 LIU Cong;MA Lifeng;JIA Weitao;LEI Junyi;LE Qichi;YUAN Yuan;PAN Hucheng(College of Mechanical Engineering,Taiyuan University of Science and Technology,Taiyuan 030024;Key Laboratory of Electromagnetic Processing of Materials,Northeastern University,Shenyang 110819;National Engineering Research Center for Magnesium Alloys,Chongqing University,Chongqing 400044;Key Laboratory for Anisotropy and Texture of Materials,Northeastern University,Shenyang 110819)

机构地区：[1]太原科技大学机械工程学院,太原030024 [2]东北大学材料电磁加工教育部重点实验室,沈阳110819 [3]重庆大学国家镁合金材料工程技术研究中心,重庆400044 [4]东北大学材料各向异性与织构教育部重点实验室,沈阳110819

出　　处：《机械工程学报》2022年第12期93-102,共10页Journal of Mechanical Engineering

基　　金：国家自然科学基金(U1610253,U1910213);山西省青年科技研究基金(201901D211290);太原科技大学科研启动基金(20192002);山西省高等学校科技创新(2019L0614)资助项目。

摘　　要：为提高镁合金低温压缩时有限的成形性,防止过早断裂。采用铝、铜套筒约束压缩AZ31镁合金方法在变形温度200℃,应变速率0.01~1 s^(-1)条件下用Gleeble-3800热模拟试验机进行单轴压缩变形试验和有限元模拟,分析不同应变速率和不同套筒材料对AZ31镁合金成形性的影响。结果表明,与无约束压缩相比,约束镁合金压缩变形区域的应力应变呈现带状分层分布,金属约束流动使非自由变形区沿鼓型集中扩散;45°剪切开裂现象消失但在1 s^(-1)下出现45°鼓型畸变;损伤分布与组织变形程度呈负相关,与约束材料的韧性呈正相关;约束变形区孪晶和动态再结晶晶粒增加。对比分析试验和模拟结果,得到在应变速率0.01 s^(-1)下,套筒Cu约束下的镁合金变形区域分层集中,组织变形均匀性更好,损伤值较小并有效抑制开裂,使镁合金成形性得到提高。In order to improve the limited formability of magnesium alloy during low temperature compression and prevent premature fracture.Uniaxial compression deformation test and finite element simulation were carried out by Gleeble-3800 thermal simulation testing machine under the conditions of deformation temperature 200℃and strain rate 0.01-1 s^(-1),and the effects of different strain rates and sleeve materials on formability of AZ31 magnesium alloy were analyzed.The results show that,compared with unconstrained compression,the stress and strain in the compression deformation zone of confined magnesium alloy show zonal layered distribution,and the metal confined flow makes the non-free deformation zone diffuse along the drum shape 45°shear cracking disappeared but 45°drum distortion appeared at 1 s^(-1).The damage distribution is negatively correlated with the degree of tissue deformation and positively correlated with the toughness of constraint materials.Twinning and dynamic recrystallization grains increase in constrained deformation zone.Comparing the experimental and simulation results,it is found that under the strain rate of 0.01 s^(-1),the deformation area of magnesium alloy restrained by sleeve Cu is layered and concentrated,the deformation uniformity of microstructure is better,the damage value is smaller,cracking is effectively inhibited,and the formability of magnesium alloy is improved.

关 键 词：AZ31镁合金 热模拟 约束压缩 损伤 

分 类 号：TG156[金属学及工艺—热处理]