挤压态Mg-Al-Mn-(0.2Sr)镁合金的准静态压缩变形行为  

Quasi-static compression deformation behavior of extruded Mg-Al-Mn-(0.2Sr)magnesium alloys

作　　者：肖罡 郭鹏程[1,3,4] 王文韫 项忠珂[1] 杨钦文 XIAO Gang;GUO Peng-cheng;WANG Wen-yun;XIANG Zhong-ke;YANG Qin-wen(School of Artificial Intelligence,Jiangxi University of Science and Technology,Nanchang 330098,China;Jiangxi Copper Technology Research Institute Co.,Ltd.,Nanchang 330096,China;School of Mechanical and Vehicle Engineering,Hunan University,Changsha 410082,China;School of Mechanical and Electrical Engineering,Central South University of Forestry and Technology,Changsha 410004,China)

机构地区：[1]江西科技学院人工智能学院,江西南昌330098 [2]江西铜业技术研究院有限公司,江西南昌330096 [3]湖南大学机械与运载工程学院,湖南长沙410082 [4]中南林业科技大学机电工程学院,湖南长沙410004

出　　处：《塑性工程学报》2024年第4期160-168,共9页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(52075159);江西省自然科学基金资助项目(20224ACB218002);江西省高层次高技能领军人才培养工程资助项目;湖南省自然科学基金资助项目(2022JJ30019);长沙市科技计划项目(kq2208420);广西大学省部共建特色金属材料与组合结构全寿命安全国家重点实验室开放基金资助项目(2022GXYSOF24)。

摘　　要：采用准静态压缩实验研究了挤压态Mg-Al-Mn-(0.2Sr)镁合金在0.0001~0.33 s^(-1)应变速率范围内的变形行为。结果表明:挤压态Mg-Al-Mn-(0.2Sr)镁合金的流变应力响应行为具有一定的应变速率相关性,具体表现为流变应力随加载应变速率的增加呈现先降低,后增加,再降低的演变趋势。在压缩变形过程中,两种镁合金试样均产生了较为明显的动态应变时效(DSA)。产生DSA所需的临界应变随加载应变速率的增加而增加,且应力-应变曲线的锯齿类型具有强的应变速率相关性。添加Sr元素降低了镁合金沿径向压缩的流变应力,但对DSA行为具有一定的促进作用。相同应变速率下,挤压态Mg-Al-Mn-0.2Sr镁合金产生DSA的临界应变明显较小,且锯齿幅值略大。此外,Sr元素对孪生也具有一定的抑制作用,导致挤压态Mg-Al-Mn-0.2Sr镁合金的孪晶界出现不同程度的扭曲。The deformation behaviors of extruded Mg-Al-Mn-(0.2Sr)magnesium alloys were studied by quasi-static compression tests with strain rates ranging of 0.0001-0.33 s^(-1).The results show that the flow stress response behavior of the extruded Mg-Al-Mn-(0.2Sr)magnesium alloys exhibits a certain strain rate dependence.It is shown that the flow stress decreases first,then increases and then decrea-ses with the increase of loading strain rate.During compression deformation,the obvious dynamic strain aging(DSA)occurs in both kinds of magnesium alloys specimens.The critical strain required for DSA increases with the increase of loading strain rate,and the serra-tion type of stress-strain curves also shows a strong strain rate dependence.The addition of Sr element reduces the flow stress along the ra-dial compression direction of the magnesium alloy but promotes the DSA behavior to some extent.At the same strain rate,the critical strain for DSA of the extruded Mg-Al-Mn-0.2Sr magnesium alloy decreases obviously,and the serration amplitude is slightly larger.More-over,the Sr element has a certain inhibitory effect on twinning,resulting in different degrees of distortion of the twin boundaries in the ex-truded Mg-Al-Mn-0.2Sr magnesium alloy.

关 键 词：镁合金 应变速率 准静态压缩 变形行为 动态应变时效 

分 类 号：TG146.4[一般工业技术—材料科学与工程]