
409Penetration Theories
More complicated models exist for ceramic penetrations. Walker and Anderson [11] pro-
posed a penetration model for ball ammunition penetrating ceramic backed by a metal
plate. The model assumes axisymmetric behavior, that a velocity prole in both the target
and the penetrator can be specied analytically, that the rear of the projectile only experi-
ences elastic waves (i.e., the plastic waves are arrested before reaching the rear surface),
and that the shear behavior of the target can be specied as a pressure-dependent ow
stress (Mohr–Coulomb) for the ceramic with a constant ow shear stress (Von-Mises) for
the met ...