Penetration mechanisms : an investigation of the penetration of projectiles impacting finite-sized targets

Predicting penetration effectiveness of high speed fragments/projectiles is a very difficult task. Empirical, analytical, and numerical hydrodynamic methods are all used to make penetration predictions; however, these methods are limited in usefulness, and should only be used for estimation purposes and not for precise answers. To obtain valid predictions of projectile penetration, a detailed understanding of the penetration mechanisms is required, along with an understanding of the factors that influence the penetration process. The current investigation includes the evaluation of selected empirical and semi-theoretical impact models. Normal impacts of chunky (L/D = 3) lead projectiles into finite targets were conducted to verify impact theory and evaluate several factors that influence the penetration process. Factors that are found to influence the penetration process include the shape of the penetrator, as well as the density and the dynamic strength properties of the projectile and target materials. Implications about long-rod penetration and material strength effects of targets at very high impact velocities are also presented.