Interfacial bonding properties of titanium foil/steel explosive welding

To reduce titanium/steel explosive welding usage, the explosive welding between 200 μm thick TA1 titanium foil and Q235 steel was realized by using salt as a pressure transfer layer and low detonation velocity as a welding explosive. The microstructures at the interface were analyzed by metallographic microscope, scanning electron microscope and energy dispersive spectroscopy. Tensile and bending tests were carried out by a universal testing machine to test the bonding properties of the clad plate. The results show that the titanium foil/steel interface shows a regular waveform and is mainly bonded by the melting layer, which has good bonding quality. The metal near the interface produces strong plastic deformation, and the steel grains are linear. The vortex of the wave peak contains a melting block, and no holes or cracks are observed. According to the atomic ratio of Ti and Fe elements, the main components of melting block are FeTi and Fe₂Ti intermetallic compounds. The bonding interface did not separate when the three-point bending and tensile specimens were destroyed, which indicates that the clad plate has good plastic deformation ability and bonding performance. There are dimples of different sizes in the titanium and steel layers of tensile failure specimens, mainly plastic fractures.