Practical formulae for predicting the ballistic limit velocity of armour perforation by ductile hole growth

•Useful summary of available formulae for specific cavitation energy is presented•New formulae for targets with a combined Ludwik-Voce hardening law are derived•Experimental data, finite element numerical results and analytical predictions are compared•Analytical predictions are at least comparable to the numerical simulation results•Plane-strain, cavitation models are less accurate than the analytical models