Abstract: Taking Ti/Al composite plate prepared by explosive welding as an example, the transient forming process of explosive welding was reproduced by numerical simulation, and the interface characteristics of explosive welding were analyzed by experiments. The results showed that interface morphology of Ti/Al composite plate changed from flat bonding to wave bonding along the propagation direction of detonation wave due to the penetration of jet. The lower pressure at the initiation point led to the boundary effect of explosive welding. The high impact pressure in the impact zone of explosive welding was the cause of plastic deformation and grain refinement near the interface. The interface defects of ex-plosive welding were increased by high velocity impact, which provided a channel for the diffusion of atoms and realized metallurgical bonding.The results of numerical simulation were consistent with the experimental results, which revealed the forming mechanism of Ti/Al explosive welding interface.