| The pulse pressing solid-state diffusion bonding (PPDB)between 0Crl8Ni9Ti austenitic stainless steel and TA17 near a -titanium alloy was investigated. The parameters of bonding temperature, pulse pressure, pulse times' effect of tensile strength were determined and found the optimal parameters are T=825℃ ,P=8~50MPa,N= 20time,f=0.5Hz.Highest bond strength (293MPa) has been obtained for the diffusion assemblies under the optimal parameters and the bonding time was only 220 seconds.The diffusion-bonded couples thus produced were evaluated by optical microscopy, scanning electron microscopy, X-ray diffraction and energy dispersive spectroscopy. The study results showed austenitic stainless steel and titanium alloy were bonded well. The existence of γ- Fe, σ ,β-Ti,Fe2Ti and FeTi at the fractures, fracture occurs at interface between B-Ti solid-solution and Fe-Ti intermetallics, and the P-Ti solid-solution plays a dominant role on tensile strength. The key for enhancement of joint strength is increasing the ratio of solid-solution at fracture. During diffusion, Fe has a long diffusible distance and Cr occurs up hill diffusion.Comparing the pulse pressing solid-state diffusion bonding process to the certain temperature and pressure solid-state diffusion process, we can find the width of diffusion layers under the former technique was thinner than the later' and has higher tensile strength. Though calculating the diffusion of interface and growth kinetics of intermetallics and solid-solution, the coefficient of diffusion of Fe in β-Ti (in m2S-1) isD= 1.15x 105 exp(171000/RT) ,and the two equations of growth kinetics of intermetallicsand solid-solution can be obtained respectively: X = 7.1 x 10-2t1/2 exp(-112900/RT) mand X = 8.31t1/2 exp(-59000/RT) m, the diffusion ratio of Fe in β-Ti (in m2S-1) under thepulse pressing solid-state diffusion bonding is quicker than the available datas.
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