Strain hardening behavior of Mg-Y alloys after extrusion process

• 作者: Andrej Atrens Chaoyue Zhao Fusheng Pan Jiahui Shi Renju Cheng Teng Tu Xianhua Chen Zhu Luo Ziyan Li
• 来源期刊: 镁合金学报(英文)
• 学科: 工学
• 关键词: Mg-Y alloy Strain hardening TEXTURE TWINNING VPSC
• 年，卷（期）: 2019,（4）
• 页码范围: 672-680
• 页数: 9页
• 分类号: TG1

摘要

The strain hardening is an effective mode of enhancing mechanical properties in alloys.In this work,the strain hardening behaviors of Mg-xY(x=1,2,and 3 wt%)after extrusion process was investigated using uniaxial tensile tests.Results suggest that the Mg-xY alloys are composed ofα-Mg with a little amount of Mg24Y5 phase.The average grain size reduces from 19.8μm to 12.2μm as the Y content adds from 1 wt%to 2 wt%.Nevertheless,when Y content reaches 3 wt%,the grain size reaches to 12.9μm,which is close to that of Mg-2Y.The strain hardening rate decreases from 883 MPa to 798 MPa at(σ-σ0.2)=40 MPa,and Mg-2Y and Mg-3Y have the similar strain hardening response.Moreover,Mg-1Y shows an obvious ascending stage after the steep decreasing stage,which is mainly caused by the activation of twinning.The strain hardening behavior of Mg-xY is explained based on understanding the roles of the deformation mechanisms via deformation microstructure analysis and Visco-Plastic Self Consistent(VPSC)model.The variation of strain hardening characteristics with increasing Y content is related to the effects of grain size and texture.