镁/钛异种金属预置Al夹层光纤激光熔钎焊接特性  

Laser Welding-Brazing Characteristics of Dissimilar Metals Mg/Ti with Al Interlayers

作　　者：檀财旺[1,2] 巩向涛 李俐群[2] 冯吉才[1,2] 

机构地区：[1]哈尔滨工业大学(威海)山东省特种焊接技术重点实验室,山东威海264209 [2]哈尔滨工业大学先进焊接与连接国家重点实验室,黑龙江哈尔滨150001 [3]哈尔滨工业大学(威海)汽车工程学院,山东威海264209

出　　处：《中国激光》2015年第1期106-113,共8页Chinese Journal of Lasers

基　　金：哈尔滨工业大学(威海)校科研基金[HIT(WH)201416];哈尔滨工业大学先进焊接与连接国家重点实验室开放课题(AWJ-M15-08)

摘　　要：镁/钛异种金属既不反应也不互溶的特性制约着两者之间的冶金结合和可靠连接。为解决这一问题,通过中间预置铝(Al)箔对镁/钛实施激光搭接焊。调整焊接工艺参数获得较好的焊缝成形,并对界面元素扩散及连接机理进行研究。结果表明,Al中间夹层的添加能很好地改善镁/钛界面的润湿铺展,促进了界面的冶金反应。当添加的Al中间层厚度为50μm时,接头载荷是未添加的1.8倍,达到1010 N/cm。界面组织分析表明在激光直接辐照区形成了一定厚度的Al Ti3相,其余部位为Ti基化合物(α-Ti)。焊缝中第二相数量随着Al夹层厚度的增加而增多,当形成网状结构时造成焊缝变脆,降低接头拉剪载荷。The metallurgical bonding and reliable joining of Mg/Ti dissimilar metals are restricted by their nonreactive and immiscible characteristics. To overcome this problem, laser lap joining of Mg/Ti with addition of Al interlayer is carried out. Well appearances are obtained by adjusting the welding parameters. Elemental distribution across the interface and bonding mechanism are studied. The results indicate that wettability of Mg/Ti is improved with the help of Al interlayer, and thus metallurgical bonding is accelerated. When the thickness of Al interlayer is 50 μm , the shear force reaches 1010N/cm, which is 1.8 times as much as that without Al interlayer. The interfacial microstructure indicates that AlTi3 phase forms at the direct laser irradiation zone, while α - Ti is at the zone around it at the interface. The second phases in the weld zone increase with the increase of thickness of Al interlayer. The tensile- shear force decreases when network structure is formed in the weld zone.

关 键 词：光学制造 激光焊接 镁合金 钛合金 异种材料 

分 类 号：TG457.1[金属学及工艺—焊接]