Numerical simulation of residual stress in diffusion bonded TiAl/Ti/GH99 alloy joint

Finite element method was used to calculate the residual stress that developed during cooling from joining temperature while diffusion bonding TiAl-based intermetallics to Ni-based alloy with Ti interlayer. The effect of bonding temperature on the distribution of stress and joint size was investigated. The results show that the residual stress concentrated at the interfaces of Ti/GH99 and Ti/TiAl. Especially,the maximum residual stress was higher at the Ti/GH99 interface than at the Ti/TiAl interface. When the bonding temperature decreased,the distribution of stress in the joint was almost constant,while the maximum residual stress decreased. By comparing the simulated and experimental results,it was found that the simulated results agreed well with the experimental results.