Comparative analysis of oblique impact on ceramic composite systems

An experimental programme is presented which investigated the performance of oblique, ceramic/metal, bilayer composite armours. The ceramics, alumina and silicon carbide, were backed by either Rolled Homogeneous Armour steel (RHA) or 7000 series aluminium. Using a model scale tungsten penetrator at two velocities (representing current and future ordnance threats) the effect of configuration on ballistic limit or depth of penetration (DOP) areal densities was determined. Areal densities of the DOP targets decreased with increasing ceramic thickness, achieving a minimum at zero residual penetration in the backing. The bilayer targets, loaded at the ballistic limit needed a larger areal density to defeat the penetrator. This areal density also decreased with ceramic thickness but showed a minimum with respect to ceramic thickness, as a result of reduced support by the thinner metallic backing. At 1450ms−1 the most efficient system was found to be a SiC/Al, which demonstrated a 25% weight saving over the monolithic aluminium reference target. The Al-alloy backing performs better than RHA, and SiC better than Al2O3.