首页|Preparation of ultra-high ductility and high strength Mg-Sn-Zn-Zr alloy by differential thermal ECAP(DT-ECAP)induced heterogeneous structure
Preparation of ultra-high ductility and high strength Mg-Sn-Zn-Zr alloy by differential thermal ECAP(DT-ECAP)induced heterogeneous structure
扫码查看
点击上方二维码区域，可以放大扫码查看
原文链接
NETL
NSTL
万方数据
Developing high-ductility magnesium(Mg)alloys has become an imminent issue for their wide appli-cation.In this work,a new Mg-Sn-Zn-Zr alloy with ultra-high ductility(elongation,El.over 40％)and high ultimate tensile strength(UTS,～309-354 MPa)was prepared by a novel differential thermal equal-channel angular pressing(DT-ECAP).Heterogeneous structures,including bimodal grain structures and in-homogeneous distribution of second phases composed of banded structure and particle free zone(PFZ),were induced by DT-ECAP process.Based on the results of electron backscatter diffraction(EBSD),trans-mission electron microscopy(TEM),high-resolution TEM(HRTEM),and selected area electron diffraction(SAED),the bimodal grain structure originated from incomplete dynamic recrystallization(DRX)domi-nated by Zener pinning,strain-induced grain boundary migration(SIBM)and the limitation of polycrys-tallization due to lower dislocation density.Meanwhile,the bimodal distribution of second phases was highly associated with the defect density and initial structure.More importantly,the enhanced strength of DT-ECAPed alloys can be primarily attributed to hetero-deformation induced(HDI)strengthening,grain boundary strengthening,and precipitation strengthening.Moreover,HDI hardening,texture weakening or randomizing activation of non-basal slip,high density of dislocations in sub-structures,and twining in-duced superior work-hardening effect,which was highly responsible for the ultra-high ductility in sixth pass(6P)alloy.The current work provides a novel DT-ECAP process for inducing heterogeneous structure and offers beneficial insight into the development of ultra-high ductility and high strength for rare-earth-free Mg alloys via a combination of HDI strengthening and hardening and other vital mechanisms.
DT-ECAP processHeterogeneous structuresHDI strengthening and hardeningMechanical propertiesMg-Sn-Zn-Zr alloy
Tianshui Zhou、Bing Wang、Yaqin Li、Shiwen Hu、Xiaoqiang Li、Dexue Liu
展开 >
State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China
School of Materials Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China
NETL
NSTL
万方数据
