Al-Si焊丝Al/Cu异种金属冷金属过渡熔钎焊接头显微组织与性能  

Microstructure and mechanical properties of Al/Cu dissimilar metal brazed-fusion welded joint with AlSi_5 as the filler metal of cold metal transfer welding

作　　者：艾兵权 曹睿[1] 陈剑虹[1] 

机构地区：[1]兰州理工大学有色金属先进加工与再利用省部共建国家重点实验室,730050

出　　处：《焊接》2015年第3期14-17,69,共4页Welding & Joining

摘　　要：利用AlSi5焊丝作为填充材料对6061铝合金和T2纯铜进行冷金属过渡（Cold Metal Transfer,CMT）熔钎焊.通过拉伸试验评定搭接接头力学性能并采用SEM,EDS分析搭接接头的微观组织及化学成分,利用XRD进一步确定了钎焊界面产物.研究结果表明：送丝速度在6.5 ～ 7.5 m/min焊接时,焊接过程稳定,焊缝成形美观.搭接接头主要断裂在钎焊面处,最大拉剪载荷为154 N/mm.钎焊界面产物主要为CuAl,CuAl2,厚度在150μm左右,显微硬度在400 HV0.1左右.钎焊界面处形成的脆硬金属间化合物是铝铜搭接接头断裂于钎焊面处的主要原因.Al 6061/Cu-T2 brazing-fusion welding was carried out by using CMT welding with filler metal of AlSi_5.The mechanical properties of the lap joints were tested by tensile test,and the microstructure,chemical composition and phases were characterized by SEM,EDS and XRD.The results show that when the wire feeding rate is in the range of 6.5-7.5 m/min,the welding process is stable and the weld appearance is good.The fracture occurs at brazing interfaces in tensile test and the maximum tensile-shear load can reach 154 N/mm.The brazed interfaces are mainly consisted of brittle CuAl and CuAl_2 intermetallic compounds with a thickness of 150 μm and microhardness of 400 HV 0.1.The brittle intermetallic compounds formed at the brazed interfaces make the Al-Cu lap joints fracture at the brazed interfaces.

关 键 词：铝铜熔钎焊 冷金属过渡 力学性能 微观组织 化学成分 金属间化合物 

分 类 号：TG442[金属学及工艺—焊接]