Twinning and precipitation play important roles in deformation and strengthening of magnesium alloys.In this work,interfacial precipitation in{1012}twin boundaries(TBs)of a cold-stamped Mg-12Gd-1.2Zn-0.4Zr alloy was i...Twinning and precipitation play important roles in deformation and strengthening of magnesium alloys.In this work,interfacial precipitation in{1012}twin boundaries(TBs)of a cold-stamped Mg-12Gd-1.2Zn-0.4Zr alloy was investigated using atomic-resolution high-angle annular dark-field scanning transmission electron microscopy.Extended periodic segregation of Gd+Zn atoms in the~86.2°{1012}TBs with basal-prismatic facets and in the symmetric tilting TBs(obviously>86.2°)frequently occurred,resulted in the formation of new interfacial phases,namelyβ_(TB)’having a monoclinic structure in the TBs with two segregation layers andβ_(TB) having a tetragonal structure in the TBs with three or more segregation layers.The formation ofβ_(TB) clearly accelerates peak-aging and improves the alloy’s strength.展开更多
基金financially supported by the Scientific and Technological Developing Scheme of Jilin Province under grants No.YDZJ202102CXJD012,20200801048GH,20200602021ZPthe Capital Construction Founds of Jilin Province with Innovation Capacity Building under grants No.2021C038-1。
文摘Twinning and precipitation play important roles in deformation and strengthening of magnesium alloys.In this work,interfacial precipitation in{1012}twin boundaries(TBs)of a cold-stamped Mg-12Gd-1.2Zn-0.4Zr alloy was investigated using atomic-resolution high-angle annular dark-field scanning transmission electron microscopy.Extended periodic segregation of Gd+Zn atoms in the~86.2°{1012}TBs with basal-prismatic facets and in the symmetric tilting TBs(obviously>86.2°)frequently occurred,resulted in the formation of new interfacial phases,namelyβ_(TB)’having a monoclinic structure in the TBs with two segregation layers andβ_(TB) having a tetragonal structure in the TBs with three or more segregation layers.The formation ofβ_(TB) clearly accelerates peak-aging and improves the alloy’s strength.