铝基复合材料扩散焊接接合区微连接行为

Micro-bonding Behavior in the Weld Zone of Diffusion Welding for Aluminum Matrix Compete Reinforced with Particle

关键词:  铝基复合材料  扩散焊  基体  增强相

Key words:  aluminum matrix composite  diffusion welding  matrix  reinforcement

摘要:

以铝基复合材料Al₂O_3P/6061Al为对象,对该种材料扩散焊接接合区微连接行为进行了探索性的研究,分析了接头微观组织及力学性能。研究表明,扩散焊接温度对接合区的微连接行为有显著影响,当焊接温度低于铝基复合材料固相线温度时,增强相-基体、增强相-增强相之间微连接属弱连接;当焊接温度介于该种材料液、固两相温度区间时,接头区域出现液态基体金属,增强相-基体之间可以实现较好结合,同时液态金属对增强相-增强相接触部位进行渗透,使增强相-增强相接触转化为增强相-基体-增强相结合,在此基础上发现在铝基复合材料液、固两相温度区间有"临界温度"存在,为成功实现该种材料扩散连接奠定理论基础。

Abstract:

For diffusion wleding of aluminum matrix composite Al₂O_3p/6061 Al, the micro-bonding behavior of weld zone between reinforcement and matrix (R-M), reinforcement and reinforcement (R-R) was investigated. The results showed that key processing parameters af-fecting the micro-bonding behavior in the weld zone was diffusion welding temperature, The micro-bonding of R-M and R-R was weak bonding when welding temperature was below the solidus of composites. Bonding of R-M was achieved when welding temperature was between liquidus and solidus of composites, then liquid matrix metal appeared on the bonding interface. At the same time, liquid metal infiltrated the bonding zone of R-R, and the contact of R-R transformed into the bonding of R-M-R, thus the joint strength was improved obviously.It was found that there was a "critical temperature" between the solid and liquidus temperature of composites.