Low velocity perforation design of metal plates

Abstract

This article examines some recent experimental test data on the perforation of mild steel plates having thicknesses 2 ≤ H ≤ 8 mm and struck by relatively heavy masses travelling up to about 13 m/s. The plates are fully clamped around circular, square and rectangular boundaries and struck by projectiles having blunt, conical and hemispherical impact faces. It transpires that the dimensionless perforation energies are smallest for the plates struck by the blunt-faced projectiles and largest for the hemispherical ones. The perforation energies are greatest at the plate centre and are smaller near to the supporting boundaries. These latter effects are captured in an empirical equation for the dimensionless perforation energy. This equation provides a lower bound to almost all of the test data on the different plate geometries and impactor shapes and is, therefore, a useful tool for design purposes.