Abstract: Combined with the structural characteristics of the composite rod, the Gurney formula considering the influence of plastic work caused by the contraction of the flying tube is derived, and the collision speed of the flying tube is calculated by using this formula. The influence of plastic work generated by the deformation of the flying tube driven by shock wave on the collision speed is explored, and a new grooved flying tube structure is proposed, through which better welding quality can be obtained. The results of theoretical calculation and finite element analysis show that when the gap between the base rod and the flying tube is 3.5 mm, the kinetic energy obtained by the explosive explosion driving the flying tube is completely offset by the plastic deformation, and the collision speed is 0. The theoretical calculation and simulation results are in good agreement. Under the same conditions, the simulation results of the grooved flying tube structure show that the collision speed can reach 667.85 m/s and the collision angle is 13.877°, which meets the requirements of the lower limit collision speed of welding. Based on this, the two-dimensional microscopic simulation analysis results show that the combined interface presents periodic ripples and produces a large number of jets. The temperature at the combined interface exceeds the melting temperatures of the two metals, and the combined interface quality is better.