TiAl基合金及其连接技术的研究进展

综述了TiAl基合金熔焊和固态连接的研究状况,主要包括弧焊、激光焊、电子束焊、钎焊、扩散焊、自蔓延高温合成和摩擦焊等连接方法,分析了各种方法用于TiAl基合金连接时的优缺点.由于TiAl基合金室温塑性差,采用熔焊方法连接时焊后冷却速度块,接头组织淬硬倾向大,易形成固态裂纹.固态连接方法大多可控制焊接热循环,焊接过程中加热峰值温度相对较低,对母材组织影响小,可避免裂纹等缺陷,因而采用固态连接方法具有优势.如果能进一步降低冷却速度,则将熔焊方法用于TiAl基合金的连接有很好的应用前景.

Research progress in bonding technology for TiAl-based alloy

The development of fusion welding and solid state bonding technologies for TiAl-based ahoy was indicated which including arc weld- ing,laser beam welding,electron beam welding,brazing,diffusion bonding,SHS and friction welding.Meanwhile,the merits and drawbacks of those methods used to join TiAl-based alloy were analyzed.Because of the poor room temperature plasticity of TiAl-based alloy,fusion weld- ing will easily lead to solid state cracking on account of high-speed cooling and great tendency of quench hardening.On the other hand,under the condition of solid state bonding,the base metal will be affected little and the cracking was avoided on account of the controlled welding heat cycle and low peak temperature so that the solid state bonding methods possess lots of advantages.If the cooling speed could be further re- duced,the fusion welding would have good perspectives for joining TiAl-based alloy.