Manil Raj¹, M.J.N.V. Prasad¹, K Narasimhan¹; ¹IIT Bombay. MEMS Dept.

In present study, Ti-6Al-4V alloy and interstitial free steel were diffusion bonded using thin layers of copper, nickel and without interlayers at three different temperatures of 750°C, 850°C and 950°C under a constant pressure of 10 MPa for holding time of 10 minutes. The influence of bonding temperature and the effect of interlayer/s on the joint interfacial microstructure and bond strength were analyzed by electron microscopy, nanoindentation and shear testing. With increasing temperature, the characteristics of interlayers change from rich barrier to complete loss of it content and resulting the interdiffusion of the base metals. This reflected in significant variation of hardness across interface with respect to bonding characteristics. The joint produced with Ni interlayer exhibited optimum shear properties at lowest bonding temperature because of sound interface with less brittle compound.