铝合金中温自反应钎焊机理的研究  

Self-brazing Mechanism of Aluminum Alloy at Medium Temperature

作　　者：程方杰 齐书梅 杨振文[1,2] 姚俊峰 赵欢[2] CHENG Fang-jie;QI Shu-mei;YANG Zhen-wen;YAO Jun-feng;ZHAO Huan(Tianjin Key Laboratory of Advanced Joining Technology,Tianjin University, Tianjin 300072 , China;School of Materials Science and Engineering, Tianjin University, Tianjin 300072 , China)

机构地区：[1]天津大学天津市现代连接技术重点实验室,天津300072 [2]天津大学材料科学与工程学院,天津300072

出　　处：《材料工程》2018年第1期31-36,共6页Journal of Materials Engineering

基　　金：国家自然科学基金项目(51275351);天津市自然科学基金重点项目(13JCZDJC33500)

摘　　要：在AlF3-CsF共晶钎剂中添加ZnCl2和SnCl2两种活化物质,制备出可用于钎焊薄板铝合金的中温自反应钎剂。研究钎剂中活化物质含量和T形接头连接面积对接头界面组织与力学性能的影响。采用金相光学显微镜、扫描电子显微镜和能谱仪对钎焊接头微观组织、相成分、缺陷及断口形貌进行分析。结果表明:当钎剂中两种活化物质添加量都在4%(质量分数)左右时,钎焊接头连接最致密;钎焊时钎剂中的Zn2+和Sn2+与两侧母材中的Al原子发生置换反应生成液态金属Sn与Zn,与Al互溶度大的Zn迅速向母材扩散,而Sn由于在Al中固溶度小,与少量Zn和Al残留在界面上形成低熔点金属层;自反应钎剂易实现小连接面积接头的连接;接头拉伸断口中有大量韧窝存在,抗拉强度达到(58±5)MPa。ZnCl2 and SnCl2 were added to the A1F3-CsF eutectic flux, which can be used for connecting aluminum alloy sheet by self-brazing at medium temperature. The influence of the amount of ZnCl2 and SnCl2 and the size of the T-joint area on the interface microstructure and the self-brazing joint me-chanical properties was investigated. The interface microstructure, chemical compositions, defects and tensile fractography of the self-brazing joints were analyzed by metallographic microscope, scan-ning electron microscope and energy dispersive spectroscopy. The results show that the joints are soundly bonded when both the mass fractions of ZnCl2 and SnCl2 are about 4% ; the replacement reac-tions between Zn2＋ , Sn2＋ of flux and A1 atoms of base metal occur during brazing, then the liquid metals of Sn and Zn appear, a great degree of Zn which has high solid solution with A1 spreads rapidly to the base metal; Sn is distributed along the interface forming a low melting point metal layer with Zn and Al; the brazing of joints with small area can be realized easily; there are a lot of dimples on the fracture surface and the tensile strength of the brazing joint reaches （58±5）MPa.

关 键 词：铝合金 中温钎焊 自反应钎剂 界面反应 

分 类 号：TG454[金属学及工艺—焊接]