摘要
Mg/Al异种合金搅拌摩擦焊(friction stir welding,FSW)存在相容性差、接头易形成脆性金属间化合物等问题,Zn作为中间层对改善接头中脆性金属间化合物的成分及含量有重要影响。以WE43稀土镁合金和1060铝合金为研究对象,选焊接进给速度为50 mm/min、转速为1050 r/min、Zn夹层厚度为0.05 mm,进行异种合金搅拌摩擦焊试验。用X射线衍射(XRD)、扫描电子显微镜(SEM)、能谱分析(EDS)、硬度及拉伸测试等对焊接后接头的显微组织和力学性能进行研究。结果表明:添加Zn后焊缝表面无宏观变形、裂纹等缺陷;接头形成细小的Mg-Zn脆性金属间化合物Al_(5)Mg_(11)Zn_(4)、Mg-Zn,代替了无Zn接头中的Mg-Al脆性金属间化合物Al_(3)Mg_(2)、Al_(12)Mg_(17),减少了Mg-Al脆性金属间化合物的生成,从而改善接头中脆性金属间化合物(IMC)的种类与数量,添加Zn的FSW接头静载拉伸断口为脆-韧混合断裂,代替了无Zn接头的脆性断裂。因此,Zn为中间层可减少接头脆性金属间化合物的产生,提高接头的伸长率、抗拉强度等。
Mg/Al dissimilar alloy friction stir welding(FSW)has some problems,such as poor compatibility and easy formation of intermetallic compounds in joints.Zn as the intermediate layer has an important effect on improving the composition and content of intermetallic compounds in joints.WE43 rare earth magnesium alloy and 1060 aluminum alloy were selected as the research objects,and the feed speed was 50 mm/min,the rotating speed was 1050 r/min,and the thickness of Zn interlayer was 0.05 mm.The microstructure and mechanical properties of the welded joint were studied by X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),hardness and tensile test.The results show that there is no macroscopic deformation,crack and other defects on the weld surface after adding Zn.The joint forms fine Mg-Zn intermetallic compounds Al_(5)Mg_(11)Zn_(4)and MgZn,which replaces the Mg-Al intermetallic compounds Al_(3)Mg_(2)and Al_(12)Mg_(17)in the joint without Zn,reducing the generation of Mg-Al intermetallic compounds,thus improving the types and quantities of intermetallic compounds(IMC)in the joint.The static load tensile fracture of the FSW joint with Zn added is a brittle-ductile hybrid fracture,which replaces the brittle fracture of the Zn-free joint.Therefore,Zn as the intermediate layer can reduce the production of intermetallic compounds and improve the elongation and tensile strength of the joint.
作者
雷声
崔召杰
李云
张海浪
方继根
张翔
LEI Sheng;CUI Zhaojie;LI Yun;ZHANG Hailang;FANG Jigen;ZHANG Xiang(School of Mechanical and Electrical Engineering,Anhui Jianzhu University,Hefei 230601,China)
出处
《兵器材料科学与工程》
CAS
CSCD
北大核心
2024年第2期64-69,共6页
Ordnance Material Science and Engineering
基金
2022年度安徽省住房城乡建设科学技术计划项目(2022-YF068)
安徽省教育厅自然科学重点资助项目(2023AH050198)
安徽建筑大学科研项目(JY2021-C-039)。
