Zr元素含量对钛基钎料合金固溶强化的影响

Effect of Zr content on solid solution strengthening of Tibased brazing alloy

利用EET理论分析Zr元素对钛基钎料合金的固溶强化效果,得出锆含量自45%~12%变化时,Ti-Zr-15Cu-10Ni(质量分数,%)钎料合金晶胞内最大共价电子数先保持不变、而后减小再增大.当锆含量为37.5%时,Zr元素对钛基钎料合金的固溶强化作用相对较大,采用此锆含量的钎料合金Ti-37.5Zr-15Cu-10Ni(质量分数,%)对Ti3Al-Nb合金进行同质过渡液相扩散连接.在连接温度低于1 000℃条件下,钎料合金的扩散能力主要受保温时间的影响;在较高连接温度下,钎料合金的扩散能力明显提高,可在短时保温条件下形成组织均匀、无析出物的连接界面.

Based on EET theory,the effect of Zr content on solid solution strengthening of the brazing alloy was investigated. When the Zr content changed between 45%-12%,the max covalent electron number in the cell of Ti-Zr-15Cu-10Ni brazing alloy kept constant in the beginning,then decreased,and finally increased. However,when the Zr content was 37. 5%,the effect of Zr element on the solid solution strengthening of Ti-based brazing alloy was apparent. Transient liquid phase diffusion welding of Ti3Al-Nb alloy was conducted with Ti-37. 5Zr-15Cu-10Ni alloy. When the joining temperature was lower than 1 000 ℃,the diffusion ability of brazing alloy was mostly influenced by the holding time. Under higher temperature,the diffusion ability of brazing alloy improved significantly,and the joining interface with homogeneous microstructure and no precipitation formed shortly in the isothermal stage.