Mg/Al异种材料扩散焊界面组织结构及力学性能  

Microstructure and properties near interface zone of diffusion-bonded joint for Mg/Al dissimilar materials

作　　者：刘鹏[1] 李亚江[2] 王娟[2] 

机构地区：[1]清华大学先进成形制造教育部重点实验室,北京100084 [2]山东大学材料液态结构及其遗传性教育部重点实验室

出　　处：《焊接学报》2007年第6期45-48,共4页Transactions of The China Welding Institution

基　　金：哈尔滨工业大学现代焊接生产技术国家重点实验室开放课题(04008)

摘　　要：Mg／Al扩散焊接头界面区由铝板侧过渡层（Mg2Al3相）、中间扩散层（MgAl相）、镁板侧过渡层（Mg3Al2相）组成。SEM观察分析表明，在界面铝板侧扩散层与中间扩散层之间存在一定的扩散空洞，不利于获得接头性能优良的扩散焊接头。随着加热温度的升高界面抗剪强度呈现先增大再降低的趋势，当加热温度475℃，保温时间60min及压力0．081MPa时，接头可达到最大抗剪强度18．94MPa。接头界面扩散区的显微硬度范围为260～350HM，明显存在三个不同硬度分布区，随着加热温度的提高，扩散区的显微硬度及扩散区宽度也相应增加。The interface zone of Mg/Al diffusion-bonded joint is constituted with Al transition layer(Mg2Al3 phase),middle diffusion layer(MgAl phase) and Mg transition layer(Mg3Al2 phase).Some diffusion holes exist between the Al transition layer and middle diffusion layer observed by SEM.It is unfavorable to obtain diffusion-bonded joint of good performance.With the increase of heating temperature,the shear strength of joint interface shows the trend of increasing firstly and then decreasing.The highest shear strength is about 18.94 MPa when the heating temperature is 475 ℃,holding time is 60 min and pressure is 0.081 MPa.The microhardness test indicated that the microhardness of diffusion zone is about 260-350 HM.However,and the diffusion zone exist three different hardness regions.With the increase of heating temperature,the microhardness and diffusion width of interface diffusion zone increase gradually.

关 键 词：Mg/Al异种材料 真空扩散焊 显微组织 抗剪强度 

分 类 号：TG115.28[金属学及工艺—物理冶金]