PENETRATION RESISTANCE OF TITANIUM AND ULTRA-HARD STEEL AT ELEVATED VELOCITIES

Hypervelocity penetration data are reported for two high strength mate rials of potential importance for the next generation of armored vehic les-titanium and ultra-hard steel. For titanium, it is found that the mass efficiency has not achieved its hydrodynamic limit at 2.57 km/s. The observed R-t values can be explained with a penetration model that takes shear cracks into account. For ultra-hard steel, the hydrodynam ic limit for mass efficiency is achieved at 2.6 km/s. The performance of this material is also found to depend strongly on the ratio of targ et thickness to penetrator diameter.