Enhancing the mechanical performance of Al-Zn-Mg alloy builds fabricated via underwater friction stir additive manufacturing and post-processing aging  

作　　者：Changshu He Ying Li Jingxun Wei Zhiqiang Zhang Ni Tian Gaowu Qin Xiang Zhao 

机构地区：[1]School of Materials Science&Engineering,Northeastern University,Shenyang 110819,China [2]Key Laboratory for Anisotropy and Texture of Materials,Northeastern University,Shenyang 110819,China [3]Research Center for Metallic Wires,Northeastern University,Shenyang 110819,China

出　　处：《Journal of Materials Science & Technology》2022年第13期26-36,共11页材料科学技术（英文版）

基　　金：financially supported by the Project of Promoting Talents in Liaoning Province(No.XLYC1808038)。

摘　　要：Our previous studies have demonstrated that underwater friction stir additive manufacturing(FSAM)could effectively suppress the macroscale softening of the fabricated Al-Zn-Mg-Cu alloy build from top to bottom.However,the accompanying local softening problem,i.e.,a low-hardness region at the bottom of each stir zone,becomes prominent.In this study,an Al-Zn-Mg alloy with low quench sensitivity was used to fabricate a multilayered build via underwater FSAM.In-process water cooling could effectively solve the macroscale and local softening problems in the FSAM of the Al-Zn-Mg alloy and improve the mechanical performance of the build.The microhardness and ultimate tensile strength(UTS)of the water-cooled build in as-fabricated and aged states were more uniform along the building direction and higher than those of their counterparts.After 90 days of natural aging,the UTS of the water-cooled build in building and traveling directions reached 398 and 400 MPa,respectively,slightly higher than that of the base metal(392 MPa).The enhancement in the mechanical performance of the water-cooled build was attributed to a high degree of supersaturation and age-strengthening ability because of a high cooling rate of the underwater FSAM process and low quench sensitivity of the base metal.

关 键 词：Additive manufacturing Friction stir additive manufacturing Water cooling Al-Zn-Mg alloy Microstructure Mechanical property 

分 类 号：TG4[金属学及工艺—焊接] TG146[一般工业技术—材料科学与工程]