Intermetallic Reaction of the Bonding Interface of TA2/Q235 Explosive Welding Composite

During the explosive welding, the bonding interface of welded materials was fast heated due to high strain rate and drastic plastic deformation. The periodical wave interface, with an amplitude of ~300 μm and a period wavelength of ~800 μm, was identifiable as a uniform wave interface formed in the bonding interface. The details of the formation of melting zone and mixing zone of welding materials at the interface were observed. Combined with the Ti-Fe binary phase diagram and the principle of diffusion welding, the phase composition and evolution process of the melting and mixing zone of the bonding interface were investigated by transmission electron microscopy (TEM) and energy dispersive spectrometer (EDS). Significance of the intermetallic compound was found in the mixing zone and melting zone, which was mainly TiFe, TiFe2, TiO2, Fe2O3 and some other intermetallic oxides. Meanwhile, the phenomenon of the titanium agglomeration and oxygen precipitation was observed in the melting zone. The bonding interface could be determined as a mixing welding of mechanical mixing, melting, diffusion and solidification that occurred in the mixing zone, and melting welding and diffusion welding mainly occurred in the melting region.