Diffusion bonding of Ti-6Al-4V to ZQSn10-10 in vacuum

The experimental investigation of the direct diffusion bonding of Ti-6Al-4V to ZQSn10-10 was carried out in vacuum. The microstructure of bonded joint was studied by scanning electron microscopy （SEM）, energy dispersive spectroscopy （ EDS ） and the mechanical properties were detected by the tensile experiments. The microstructure and tensile strength of the joint mainly depend on the bonding temperature and bonding time. A satisfying diffusion bonded interface with a tensile strength of 73.9 MPa can be obtained under the condition of bonding temperature 850℃ for 30 rain. Three kinds of reaction products were observed in the bonded interface, namely β-Ti, CoaTi and CuSn3Ti5. And the brittle Cu3Ti and CuSn3 Ti5 are mainly responsible for lowering the strength of the bonded joint. The diffusion distances of Sn , Cu and Ti and square root of bonding time are approximately linear relationship. And diffusion velocity of Sn, Cu and Ti in the diffusion reaction layer are 0. 013 9,0. 069 7 and 0. 056 4 mm^2/s.