扩散焊接条件下复合材料接合区界面行为研究

对复合材料SiCw-6061A1扩散焊接接合区基体-基体、弱吉相-基本、弱强相-增强相三种界面行为进行了探索性的研究,分析了接头微观组织及其力学性能。研究表明,在试验范围内,当焊接温度低于复合材料固相线温度时,基体-基体界面可以实现良好结合,而增强相-基体-增强相-增强相界面难以实现结合。发现在铝基复合材料SiCw-6061Al液、固两相温度区间存在一个“临界温度”,当焊接温度达到该温度时,接合区出现一定数量的液态基体金属,不仅基体-基体、增强相-基体界面可以实现较好结合,而且增强相-增强相界面将转化为增强相-基体-增强相界面,焊接接头强度达到母材强度;在此基础上首次提出“非夹层液相扩散焊接”新工艺,成功实现复合材料SiCw-6061Al扩散连接。

Study of interface behavior in weld zone of diffusion welding for composite

Aluminum matrix composite SiCw 6061Al was welded through diffusion welding, and the interface behavior of weld zone between reinforcement and matrix (R M), reinforcement and reinforcement (R R) was investigated. The results show that key processing parameters affecting the interface behavior in the weld zone are diffusion welding temperature,interface of R M and R R is weak bonding when welding temperature is below the solidus of composite. It is found that a critical temperature exists between solid and liquid phrase line of aluminum matrix composite SiCw 6061Al. When diffusion welding temperature reaches the critical point, not only the interface between matrix reinforcement can obtain a better bonding, but also the interface of reinforcement reinforcement can be changed into reinforcement matrix reinforcement by penetrating molten matrix into the interface of reinforcement reinforcement, and the strength of the welded joint reaches the strength of composite. Based on experimental results, the authors firstly point out that liquid phase diffusion welding with nonlayer technology can successfully bond SiCw 6061Al composite.