Mg/Zn/Al瞬间液相过冷连接界面的组织与性能研究

采用瞬间液相过冷连接方法对AZ31镁合金/锌中间层/5083铝合金进行连接,利用SEM、XRD、拉伸实验机和微观硬度计对结合界面的微观组织、力学性能进行了表征。结果表明,以锌作中间层,采用瞬间液相过冷连接可以实现AZ31镁合金与5083铝合金的有效连接,接头的最高抗拉强度可以达到38.5MPa,随着低温扩散保温时间的延长,扩散层厚度随之增加,接头的抗拉强度也随之升高;接头的拉伸断口属于脆性断裂,结合界面形成了MgZn2和少量的Mg17Al12金属间化合物;结合界面的微观硬度最高达170。

Microstructure and mechanical properties of super-cooled process for transient liquid phase diffusion bonding zone of Mg/Zn interlayer /Al

The AZ31 Mg alloy/Zn interlayer/5083 Al alloy was joined by super-cooled process for transient liquid phase diffusion bonding.The joints were investigated for microstructural features,phase structure,microhardness,mechanical properties by scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),microhardness tester and X-ray diffractometer.The experiment results show that Mg/Al could be bonded by super-cooled process for transient liquid phase(TLP) bonding technology using Zn as interlayer and the highest tensile strength of the joints was 38.5MPa,as the diffusion holding time at low temperature was prolonged,found that the diffusion layer thickness and tensile strength increase,and the tensile fracture was brittle fracture.There are the intermetallic compounds MgZn2 and little Mg17Al12,and the highest hardness was 170 in the joint zone.