Crystallographic texture engineering is a key strategy for enhancing the mechanical properties of polycrystalline magnesium(Mg)alloys.Due to the intrinsic anisotropy of the hexagonal close-packed(HCP)structure,the def...Crystallographic texture engineering is a key strategy for enhancing the mechanical properties of polycrystalline magnesium(Mg)alloys.Due to the intrinsic anisotropy of the hexagonal close-packed(HCP)structure,the deformation behavior of Mg alloys is significantly governed by individual grain deformation and multi-grain interactions,both dictated by crystallographic texture.In the current study,enhanced ductility was achieved in a Mg-Al-Zn-Mn dilute alloy by tailoring a strong basal texture into a transverse-direction-spread elliptical texture through the minor addition of yttrium(Y).Systematic quasi-in-situ electron backscatter diffraction(EBSD)and dislocation/disclination density analyses were performed to examine the microstructural evolution during deformation.We found that disclinations emerge from defect reactions,including dislocation-grain boundary(GB)and twin-GB interactions,which facilitate twinning plasticity and intergranular accommodation in the elliptical-textured alloy,resulting in improved work-hardening capacity and higher ductility(28.5% along the rolling direction and 32.2%along the transverse direction).By introducing disclination analysis to elucidate defect reactions,multi-grain interactions and the associated microstructure-property relationships in polycrystalline metals,our work provides new insights into the design of advanced Mg alloys with enhanced ductility and formability through crystallographic texture engineering.展开更多
基金Financial supports from The National Natural Science Foundation of China (Nos. U22A20109, 52171116 and 52334010)Partial financial support came from The Program for the Central University Youth Innovation TeamThe Fundamental Research Funds for the Central Universities, JLU.
文摘Crystallographic texture engineering is a key strategy for enhancing the mechanical properties of polycrystalline magnesium(Mg)alloys.Due to the intrinsic anisotropy of the hexagonal close-packed(HCP)structure,the deformation behavior of Mg alloys is significantly governed by individual grain deformation and multi-grain interactions,both dictated by crystallographic texture.In the current study,enhanced ductility was achieved in a Mg-Al-Zn-Mn dilute alloy by tailoring a strong basal texture into a transverse-direction-spread elliptical texture through the minor addition of yttrium(Y).Systematic quasi-in-situ electron backscatter diffraction(EBSD)and dislocation/disclination density analyses were performed to examine the microstructural evolution during deformation.We found that disclinations emerge from defect reactions,including dislocation-grain boundary(GB)and twin-GB interactions,which facilitate twinning plasticity and intergranular accommodation in the elliptical-textured alloy,resulting in improved work-hardening capacity and higher ductility(28.5% along the rolling direction and 32.2%along the transverse direction).By introducing disclination analysis to elucidate defect reactions,multi-grain interactions and the associated microstructure-property relationships in polycrystalline metals,our work provides new insights into the design of advanced Mg alloys with enhanced ductility and formability through crystallographic texture engineering.
