Empirical tests of a model for thin plate perforation

This work presents a series of mechanical and ballistic tests designed to the test the material assumptions used in, and the performance of, a model for the perforation of thin metallic plates by blunt cylindrical missiles. Tensile, bend and shear test data show reasonable concurrence with the simplified forms assumed for the model. Quasi-static punching and dishing test data demonstrate the importance of dishing as an energy absorbing mechanism, and provide simplified perforation data for comparison with ballistic limit velocity. Predictions of ballistic limit velocities at two scales are good, provided yaw of the projectile is negligible. Large amounts of projectile yaw can lead to a low energy failure by a mechanism of cutting, shearing and bending of the plate. In addition an unusual hinging failure mechanism is observed, particularly for thin plates, and attributed to modification of the stress fieldby unloading around the crack during the progress of propagation of the failure itself.