7A52铝合金搅拌摩擦焊焊缝第二相分析及微区电位测试  

Analysis and volta potential measurement of second phases in friction stir welding seam of 7A52 aluminum alloy

作　　者：张平[1] 李奇[1] 赵军军[1] 

机构地区：[1]装甲兵工程学院装备再制造技术国防科技重点实验室

出　　处：《焊接学报》2011年第8期42-44,115,共3页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(50801066)

摘　　要：7A52铝合金搅拌摩擦焊焊缝第二相的种类、大小、分布和电位等都对材料的腐蚀行为有重要的影响.采用光学显微镜、扫描电镜、能谱分析仪、扫描开尔文探针力显微镜分析了焊缝中的第二相,并测试了其微区电位.结果表明,焊缝各区域第二相的组成主要为弥散分布的AlFeMnSi和Mg2Si,它们的尺寸约为几微米,电位都低于基体.Mg2Si的电位值低于AlFeMnSi,故在腐蚀环境中,Mg2Si更容易腐蚀.这为深入分析7A52铝合金搅拌摩擦焊焊缝的腐蚀行为奠定了基础.The species,size and volta potential of intermetallics of friction stir welding seam of 7A52 aluminum alloy have important influence on its corrosion behavior.The interemtallics of the welded seam were observed and characterized with metallographic microscope,scanning electron microscope,energy dispersive spectrometer and scanning Kelvin probe force microscope,and the volta potential of the welded seam was tested.The results indicate that the irregularly shaped intermetalics AlFeMnSi and Mg2Si disperse in the welded seam,which sizes are several microns and volta potentials are lower than the matrix.The volta potential of Mg2Si is lower than that of AlFeMnSi intermetalics,which means that Mg2Si is easier to be corroded in erosive environments.The results lay the foundation of studying corrosion behavior of friction stir welding seam of 7A52 aluminum alloy.

关 键 词：7A52铝合金 搅拌摩擦焊 焊缝 第二相 微区电位 

分 类 号：TG453[金属学及工艺—焊接]