Study of diffusion bonding of Ti-6Al-4V and ZQSn10-10 with metal interlayer

The diffusion bonding was carried out to join Ti alloy(Ti-6Al-4V) and tin-bronze(ZQSn10-10) with Ni and Ni+Cu interlayer.The microstructures of the diffusion bonded joints were analyzed by scanning electron microscope(SEM),energy dispersive spectroscopy(EDS) and X-ray diffraction(XRD).The results show that when the interlayer is Ni or Ni+Cu transition metals both could effectively prevent the diffusion between Ti and Cu and avoid the formation of the Cu-Ti intermetallic compounds(Cu3Ti,CuTi etc.).But the Ni-Ti intermetallic compounds(NiTi,Ni3Ti) are formed on the Ti-6Al-4V/Niinterface.When the interlayer is Ni,the optimum bonding parameters are 830℃/10 MPa/30min.And when the interlayer is Ni+Cu,the optimum bonding parameters are 850℃/10MPa/20min.With the optimum bonding parameters,the tensile strength of the joints with Ni and Ni+Cu interlayer both are 155.8MPa,which is 65 percent of the strength of ZQSn10-10 base metal.