(中南大学 粉末冶金国家重点实验室，长沙 410083)
摘 要: 对Mg/Al异种金属进行真空扩散焊接，采用SEM和XRD等手段分析接头界面微观结构和相成分，研究Mg/Al界面组织结构的演变规律，测试接头的抗弯强度。结果表明：真空扩散焊接能够实现Mg1/Al1060的连接；扩散焊接过程中，界面发生扩散反应生成中间相Mg2Al3和Mg17Al12，且Mg2Al3相生长速率要快于Mg17Al12相；中间相由初始的岛状组织，经纵向长大相互连接，最后形成均匀平直的扩散反应层；接头最高抗弯强度为36.3MPa，断裂发生在扩散反应层，属于准解理断裂。
关键字: 真空扩散焊接；Al1060；Mg1；显微组织；抗弯强度
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:The dissimilar metals of Mg and Al were welded by vacuum diffusion bonding. The microstructure and phase constitution at the interface of Mg/Al joints were characterized via SEM and XRD, and the evolution rule of interface microstructure was analyzed. The bending strength of the joints was tested. The results indicate that Mg1 and Al1060 can be joined by vacuum diffusion bonding. In the diffusion process, the intermediate phases of Mg2Al3 and Mg17Al12 form when the diffusion reaction occurs at the interface, and Mg2Al3 phase grows faster than Mg17Al12 phase. The island-like structures formed by intermediate phases gradually links to each other by longitudinal growth and finally forms a uniform and flat diffusion layer. The highest bending strength of the joint is 36.3 MPa and a fracture occurs in the diffusion layer which belongs to quasi-cleavage fracture.
Key words: vacuum diffusion bonding; Al1060; Mg1; microstructure; bending strength
