Ti-Nb作缓冲层的TiC金属陶瓷/不锈钢脉冲加压扩散连接

Diffusion Bonding of TiC cermet to Stainless Steel using Impulse Pressuring with Ti-Nb Interlayer

摘要:

采用Ti-Nb中间层对TiC金属陶瓷和不锈钢06Cr19Ni10进行了脉冲加压扩散连接,以实现缩短焊接时间并缓解界面产物对接头的有害作用的目的。连接温度890℃,脉冲压力2~10MPa工艺条件下,在4~12min时间内即实现了陶瓷与不锈钢的有效连接,与传统扩散焊相比连接时间大幅缩短。对接头进行显微组织表征发现在反应界面处存在溶解了少量Nb的σ相以及溶解了Ni的α β-Ti固溶体。在连接时间为10min时得到了最大的剪切强度110MPa。在剪切载荷下,接头沿着剩余的Ti/α β-Ti界面扩展至陶瓷内部断裂。结果表明,脉冲加压扩散连接能在一定程度上缩短焊接时间,中间层Ti/Nb的合理选择能很好的抑制了有害的金属间化合物的生成。

关键词:TiC陶瓷; 扩散连接;脉冲压力;Ti-Nb; 微观组织

Abstract:

_{:Impulse pressuring diffusion bonding (IPDB) of TiC cermet to stainless steel 06Cr19Ni10 using Ti-Nb interlayer was carried out in an attempt to reduce the bonding time and alleviate the detrimental effect of interfacial reaction products on bonding strength. Successful bonding was achieved at 890℃ under a pulsed pressure of 2~10MPa within a duration of only 4~12min, which was notably shortened in comparison with conventional diffusion bonding. Microstructure characterization revealed the existence of the σ phase with a limit solubility of Nb, (β-Ti, Nb) phase, and solid solution of Ni in α β-Ti in the reaction zone. Maximum shear strength of 110MPa was obtained when the joint was bonded for 10min, indicating a robust metallurgical bonding was achieved. Upon shear loading, the joints fractured along the remnant Ti/ α β-Ti interfaceand extended to the interior of TiC cermet in a brittle cleavage manner. This technique provides a highly promising bonding method of TiC cermet and steel.}

Key words:TiC cermet; diffusion bonding; impulse pressuring; Ti-Nb; microstructure