Objectives  The FE method cannot accurately simulate crevasse patterns and the crevasse forming process when dealing with a projectile penetrating into a ship's plate because of mesh distortion.

  Methods  To this end, this paper establishes a numerical simulation model of a projectile's penetrating shell structure based on the Material Point Method (MPM) and successfully simulates the failure process of crevasses. A comparison is made between the simulation results and the experimental results, showing that the MPM simulation results match the experimental results more closely, thus verifying the effectiveness of researching the crevasse failure process in the context of a projectile penetrating a ship's plate and providing a new approach to researching missiles penetrating a ship's shell plate. On the basis of the simulation model, simulations are made of a projectile penetrating 5 mm and 10 mm target plates with various velocities.

  Results  The findings indicate that the crevasse size and plastic deformation area of the target plates are basically unchanged, and the crevasse size is slightly larger than the diameter of the projectile, with a 'washing crevasse' fracture mode. The target plate exhibits a plugging failure mode when hemispherical head projectiles penetrate such as the hull of shup at low, medium and high speed, and the speed has little influence on the size of the crevasses in the target plates while having a great influence on the height of the bump at the crevasse.

  Conclusions  The results of this study can provide useful references for the protection design of ship structures.