Tension-compression asymmetry and corresponding deformation mechanism in ZA21 magnesium bars with bimodal structure

作     者：Yujiao Wang Yun Zhang Haitao Jiang Wang Yujiao;Zhang Yun;Jiang Haitao

作者机构：Institute of Engineering TechnologyUniversity of Science and Technology BeijingBeijing 100083China Beijing Institute of Machinery and EquipmentBeijing 100854China 

出 版 物：《International Journal of Minerals,Metallurgy and Materials》 (矿物冶金与材料学报（英文版）)

年 卷 期：2023年第30卷第1期

页      面：92-103页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：financially supported by the National Natural Science Foundation of China (No. 52275305) the Fundamental Research Funds for the Central Universities (No. FRF-IC-20-10) the China Postdoctoral Science Foundation (No. 2021M700378) 

主　　题：bimodal structure deformation mechanism Hall-Petch relationship tension-compression asymmetry twin variant selection 

摘      要：We investigated the asymmetric tension-compression(T-C)behavior of ZA21 bars with bimodal and uniform structures through axial tension and compression *** results show that the yield strengths of bars having bimodal structure are 206.42 and 140.28 MPa under tension and compression,respectively,which are higher than those of bars having uniform structure with tensile and compressive yield strength of 183.71 and 102.86 MPa,*** slip and extension twinning under tension and basal slip and extension twinning under compression dominate the yield behavior and induce the T-C ***,due to the basal slip activated in fine grains under tension and the inhibition of extension twinning by fine grains under compression,the bimodal structure possesses a lower T-C asymmetry(0.68)compared to the uniform structure(0.56).Multiple extension twins occur during deformation,and the selection of twin variants depends on the Schmid factor of the six variants activated by parent ***,the strengthening effect of the bimodal structure depends on the grain size and the ratio of coarse and fine grains.