摘要
电弧增材制造(WAAM)技术制备的中低稀土含量镁合金有望通过直接时效处理即可获得优异的力学性能。采用电弧增材制造技术制备Mg-5Gd-2Y-0.4Zr合金,并对其微观组织和直接时效处理的力学性能进行研究。结果表明:沉积态合金具有晶粒尺寸细小(≤26μm)、基体内合金元素含量高以及晶间第二相少的特征。经过200℃×128h直接时效热处理后,合金的硬度从(63.3±2.2)HV_(0.3)提升至(85.1±2.1)HV_(0.3),达到固溶时效态硬度的95.6%;合金的抗拉强度、屈服强度也分别由(217.3±2.8)MPa、(91.0±7.7)MPa提升至(240.3±1.6)MPa、(130.9±2.5)MPa。Mg-5Gd-2Y-0.4Zr合金力学性能的显著提升,展现出直接时效处理的显著强化作用。
The magnesium alloy with medium and low rare earth content,fabricated by wire and arc additive manufacturing(WAAM),is expected to achieve excellent mechanical properties through direct aging treatment.The Mg-5Gd-2Y-0.4Zr alloy was fabricated by the WAAM,and its microstructure and mechanical properties under direct aging heat treatment were studied.The results indicate that the as-deposited alloy exhibits a fine grain size(≤26μm),a high content of alloying elements in the matrix,and few intergranular second phases.After direct aging treated at 200℃for 128h,the hardness of direct aging treated alloy increased from(63.3±2.2)HV_(0.3) to(85.1±2.1)HV_(0.3),reaching 95.6%of the hardness sf solution+aging treated alloy;while the tensile strength and yield strength increased from(217.3±2.8)MPa and(91.0±7.7)MPa to(240.3±1.6)MPa and(130.9±2.5)MPa,respectively.In conclusion,this study demonstrates that direct aging treatment has a remarkably strengthening effect on the mechanical properties of Mg-5Gd-2Y-0.4Zr alloy.
作者
涂煜璇
郑冬冬
王军凯
李卓
TU Yuxuan;ZHENG Dongdong;WANG Junkai;LI Zhuo(Ningbo Institute of Technology,Beihang University,Ningbo 315800,Zhejinag,China;National Engineering Laboratory of Additive Manufacturing for Large Metallic Components,Beihang University,Beijing 100191,China)
基金
国防基础科研计划(No.JCKY2021601B203)。
关键词
电弧增材制造
镁合金
直接时效处理
力学性能
wire and arc additive manufacturing
magnesium alloy
direct aging treatment
mechanical property
