引入梯度双模态组织提升挤压态AZ31棒材的拉伸性能  

Enhancing tensile properties of extruded AZ31 rod by introducing gradient bimodal microstructure

作　　者：尚琦 吴凡[1] 陈红兵[2] 张红菊[3] 刘婷婷[1] 郭宁[1] 郭胜锋[1] 宋波[1] Qi SHANG;Fan WU;Hong-bing CHEN;Hong-ju ZHANG;Ting-ting LIU;Ning GUO;Sheng-feng GUO;Bo SONG(School of Materials and Energy,Southwest University,Chongqing 400715,China;College of Engineering and Technology,Southwest University,Chongqing 400715,China;Analytical&Testing Center,Southwest University,Chongqing 400715,China)

机构地区：[1]西南大学材料与能源学院,重庆400715 [2]西南大学工程技术学院,重庆400715 [3]西南大学分析测试中心,重庆400715

出　　处：《Transactions of Nonferrous Metals Society of China》2023年第12期3673-3684,共12页中国有色金属学报（英文版）

基　　金：financially supported by the Natural Science Foundation of Chongqing,China(No.cstc2021jcyj-msxm X0433);the Chongqing Foundation of Science and Technology,China(Nos.cstc2020jxjl X0001,cstc2021jxjl50004);the National Natural Science Foundation of China(No.51601154)。

摘　　要：利用350℃下的往复扭转制备具有梯度双模态显微组织的镁合金棒。详细研究双模态显微组织对合金拉伸性能和变形机制的影响。梯度双模态显微组织的形成归因于不完全动态再结晶和扭转变形的特点。双模态结构对屈服强度的影响较小,但极大增加了峰值应力和拉伸延展性。由梯度双模态显微组织产生的大异质变形诱导的强化是应变硬化能力和拉伸延展性提升的原因。最后,讨论了相关的变形机制。The Mg alloy rods with a gradient bimodal microstructure were fabricated by forward-reverse torsion at 350℃.The effects of the bimodal microstructure on tensile properties and deformation mechanism of the alloy were investigated in detail.The formation of gradient bimodal microstructure was attributed to the incomplete dynamic recrystallization and the characteristic of torsion deformation.The bimodal structure had less influence on the yield strength but largely increased the peak stress and tension ductility.The large heterogeneous deformation-induced strengthening via gradient bimodal microstructure was responsible for the enhanced strain hardening capacity and tensile ductility.Finally,the related deformation mechanisms were discussed.

关 键 词：镁合金 热扭转 双模态显微组织 异质变形 拉伸性能 

分 类 号：TG146.22[一般工业技术—材料科学与工程]