Numerical Simulation Analysis of Back Fragmentation of Sphere by Hypervelocity Impact

The appropriate material state equations and strength models were chosen. Through the numerical simulation results, the fragmentation behavior of the projectile material is analyzed. The fragmentation of the projectile mainly consists of spallation caused by release waves and fragmentation of the material under high pressure. Due to the influence of the spallation and the fragmentation method of the projectile under the influence of high pressure, It also causes the shape and size of the fragments produced by the material in two cases. This paper analyzes the propagation and attenuation of pressure pulses in a projectile during the impact of a spherical projectile on a target plate. It was found that the pulse width of the pressure pulse in the projectile remained substantially unchanged when the size of the projectile and the target were the same, and the peak pressure increased as the impact velocity increased. At the same impact velocity, the peak pressure of the pressure pulse propagating in the projectile is substantially constant, and the pulse width of the pressure pulse increases as the thickness of the target increases. The pressure pulse propagated in the projectile is related to the spallation of the back surface of the projectile. The peak value and rate of change of the pressure pulse directly affect the thickness of the back surface layer. The width of the pressure pulse directly affects the depth of the lamination of the back surface along the radial direction of the projectile. The affected area of the fracture-cracking method and the thickness of the spar are obtained, which have important reference value for the distribution of fragments in the debris cloud in the later stage.