铝/钢金属超声波辅助激光熔钎焊组织及性能  

Microstructure and mechanical properties of Al/steel metal by ultrasonic-assisted laser welding-brazing

作　　者：张洋[1] 郭玉奇 曹雅彬[1] 齐海波[1] Zhang Yang;Guo Yuqi;Cao Yabin;Qi Haibo(Shijiazhuang Tiedao University,Shijiazhuang 050043,China)

机构地区：[1]石家庄铁道大学

出　　处：《焊接》2019年第9期14-19,I0021,共7页Welding & Joining

基　　金：国家自然科学基金项目(51705344,51775359);河北省高等学校科学技术研究青年基金项目(QN2015038)

摘　　要：采用Al-Si合金作为填充金属,在超声波辅助激光熔钎焊条件下,实现了铝/钢异种材料的连接。研究了超声振动对接头界面结构、焊缝金属的晶粒尺寸及力学性能的影响。不施加超声振动时,在焊缝与钢的界面热源中心处形成了三层总厚度范围为8.3~12.3μm的金属间化合物,远离热源中心处金属间化合物厚度范围为1.5~2.6μm,接头强度较低且断裂位于焊缝与钢的界面处。应用700 W超声振动后,填充金属对钢的润湿能力增加,焊缝晶粒尺寸由32μm降低至19μm,界面处金属间化合物为0.5~1.0μm的连续薄层θ相。这些共同导致断裂改变至铝合金侧熔合线附近的焊缝中,接头强度是不施加超声振动时强度的1.6倍。Ultrasonic assisted laser welding-brazing technique was used for joining of 6061 aluminum alloy to steel dissimilar materials with Al-Si filler metal.Effects of ultrasonic vibration on joint interfacial microstructure,grain size and mechanical properties of the weld were investigated.Without ultrasonic vibration,three layers of intermetallic compounds(IMC)with the thickness range of 8.3~12.3μm were observed in the heat source center of the interface between the weld and steel.The IMC thickness range away from the heat source was 1.5~2.6μm.The joint strength was low and the joint failed at the interface of the weld and steel.When the ultrasonic power was 700 W,the spreading width of filler metal on the steel increased and the crystalline grain size decreased from 32μm to 19μm.The interfacial IMC was a continuous thin layerθphase with a thickness of 0.5~1.0μm.These changes led to the weld failure near aluminum fusion line and improved the joint strength by 1.6 times of that without ultrasonic assisted.

关 键 词：超声振动 激光熔钎焊 铝/钢异种材料 金属间化合物 

分 类 号：TG456[金属学及工艺—焊接]