Effect of axial preloading on mechanical behavior during the free-end torsion of an extruded AZ31 magnesium alloy  

作　　者：Qun Li Dan Meng Zhichang Fu Hui Zhao Chong Yang Yan Peng Baodong Shi 

机构地区：[1]Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of Education,School of Mechanical Engineering,Yanshan University,Qinhuangdao 066004,China [2]National Engineering Research Center for Equipment and Technology of Cold Rolled Strip,School of Mechanical Engineering,Yanshan University,Qinhuangdao 066004,China [3]State Key Laboratory of Metastable Materials Science and Technology,Yanshan University,Qinhuangdao 066004,China

出　　处：《International Journal of Minerals,Metallurgy and Materials》2022年第7期1351-1360,共10页矿物冶金与材料学报（英文版）

基　　金：financially supported by the projects by the National Natural Science Foundation of China (No. 51771166);the Hebei Natural Science Foundation, China (Nos. E2019203452 and E2021203011);the central government guiding local science and technology development (No. 216Z1001G);the talent project of Human Resources and Social Security Department of Hebei Province, China (No. A202002002);the key project of the Department of Education of Hebei Province (No. ZD2021107);the Cultivation Project for Basic Research and Innovation of Yanshan University (No. 2021LGZD002);the State Key Laboratory of Materials Processing and Die & Mould Technology, Huazhong University of Science and Technology, China (No. P2020-013)

摘　　要：Large plastic deformation commonly occurs during the practical forming process in industries.Compared with uniaxial tension/compression,torsion is a more effective approach to investigate mechanical behavior under large deformation.The response of the large strain torsion of magnesium alloy is sensitive to the initial texture and twinning.Therefore,an extruded AZ31 alloy was pre-stressed in tension and compression to introduce dislocations and twins in the current work.Subsequently,torsion tests were conducted to clarify the effects of twinning and dislocation on subsequent deformation responses.The corresponding microstructure and deformation mechanisms were explored on the basis of viscoplastic self-consistent(VPSC)modeling.The experimental observations on stress-strain responses and pole figures were captured by simulation work.It was found that twins make less contribution to plastic deformation,which results in small change in texture direction under pure torsion and torsion after pretension.The activity of the slip/twin system and the mechanical properties are affected by different initial textures and active conditions of the system.Moreover,the stress state during combined tension-torsion loading benefits the reduction of texture intensity.

关 键 词：magnesium alloy TORSION TWINNING DISLOCATION texture viscoplastic self-consistent 

分 类 号：TG146.22[一般工业技术—材料科学与工程]