Roll Bonding of Titanium Clad Steel Using Nickel Interlayer

Cladding of steel with titanium alloys to improve corrosion behavior and to reduce production costs، is used widely in aerospace، chemical، nuclear and biomaterials industries. Roll bonding is one of the solid state processes to produce this combination. In this research the high quality bonding of hot roll bonding of titanium on steel substrate was investigated in terms of physical and mechanical properties، and the effect of nickel interlayer to prevent interdiffusion was evaluated. The microstructure at interface was observed by an optical and scanning electron microscope and the presence of intermetallic phases in the reaction zone was examined by X-ray diffraction on surfaces of the joints. The experimental results showed that the no reaction layer will be formed at the interface of steel with nickel but The interface between titanium alloy and nickel consists of the several diffusion layers include the intermetallic compounds of TiNi3، TiNi، Ti2Ni and their mixture so that the total thickness of intermetallic layers at the interface between titanium and nickel and the hardness of roll bonded joints increases with the bonding temperature