Thermal deformation behavior and holes evolution at weld interface of diffusion bonded TC4 titanium alloy
The constant strain rate tensile tests of diffusion bonded TC4 titanium alloy were conducted on UTM5504X electronic universal testing machine to study the thermal deformation behaviors of the material at the deformation temperature of 680-920 ℃ and the strain rate of 0.0001-0.1s1.The difference of microstructure between the diffusion bonded TC4 titanium alloy and original TC4 titanium alloy was analyzed by optical microscope,and the effect of different deformation parameters on the holes of weld interface was studied.The results show that the acicular α phase in the diffusion bonded TC4 titanium alloy is obviously coarsened compared with original TC4 titanium al-loy.With the increase of deformation temperature and the decrease of strain rate,the peak stress gradually decreases.At deformation tem-perature of 680-800 ℃ and strain rate of 0.0001-0.01 s-1,diffusion bonded TC4 titanium alloy tends to fracture along the weld inter-face.When the deformation temperature is 920 ℃ and the strain rate is 0.0001 s-1,diffusion bonded TC4 titanium alloy fractures along the weld interface,and the elongation is 237.1％.When the true strain is constant,the proportion of holes at the weld interface decreases with the increase of deformation temperature and the decrease of strain rate.
NETL
NSTL
万方数据
