Due to their unique precipitation behavior,magnesium-rare earth(Mg-RE)alloys exhibit excellent strength and high thermal stability.However,owing to the negative blocking effect of precipitation on dislocation slipping...Due to their unique precipitation behavior,magnesium-rare earth(Mg-RE)alloys exhibit excellent strength and high thermal stability.However,owing to the negative blocking effect of precipitation on dislocation slipping,the plasticity and ductility of Mg-RE alloys become deteriorate after aging treatment.In this work,a novel strategy to improve the combination of strength and ductility by designing a laminate heterostructured Mg alloy is proposed.High-pressure torsion(HPT)processing is employed to fabricate a clean and well-bonded interface between MgGdYAg and MgAg alloys.The two alloys have huge differences in precipitation hardening,and ductility is improved due to two facts.For one thing,the density of the second phases in the MgAg alloy is much lower than that of MgGdYAg alloy;for another,the non-basal〈c+a〉slipping is continuously activated during deformation.Through this mechanism,the uniform elongation of the heterostructured MgAg/MgGdYAg/MgAg alloy is improved to 7.1%.展开更多
基金supported by the Key Program of National Natural Science Foundation of China(No.51931003)the National Natural Science Foundation of China(Nos.52171118 and 52201124 and U22A20187)+4 种基金the China Postdoctoral Science Foundation(No.2021M701715)the Jiangsu Funding Program for Excellent Postdoctoral Talent(No.2022ZB279)the Project Internationalized Construction of Teachers of Jiangsu University(NO.4023000059)the Projects in Science and Technique Plans of Ningbo City(No.2019B10083)the Opening Project of the Key Laboratory of Advanced Manufacturing and Intelligent Technology(Ministry of Education)of Harbin University of Science and Technology(No.KFKT202103).
文摘Due to their unique precipitation behavior,magnesium-rare earth(Mg-RE)alloys exhibit excellent strength and high thermal stability.However,owing to the negative blocking effect of precipitation on dislocation slipping,the plasticity and ductility of Mg-RE alloys become deteriorate after aging treatment.In this work,a novel strategy to improve the combination of strength and ductility by designing a laminate heterostructured Mg alloy is proposed.High-pressure torsion(HPT)processing is employed to fabricate a clean and well-bonded interface between MgGdYAg and MgAg alloys.The two alloys have huge differences in precipitation hardening,and ductility is improved due to two facts.For one thing,the density of the second phases in the MgAg alloy is much lower than that of MgGdYAg alloy;for another,the non-basal〈c+a〉slipping is continuously activated during deformation.Through this mechanism,the uniform elongation of the heterostructured MgAg/MgGdYAg/MgAg alloy is improved to 7.1%.
