Influence of panel/back thickness on impact damage behavior of alumina/aluminum armors

Using modified SHPB device, damage behaviors of alumina/aluminum armors under impact load were studied. The influences of panel/back thickness on the target damage characteristics were investigated. The transmitted stress wave increased and the reflected stress wave decreased distinctly with the increase of back thickness, while the panel thickness variation had little influence on the stress wave propagation features. The vertex angle of ceramic inverted cone increased with the increase of back thickness and decrease of panel thickness, but the number of radial cracks reduced with the increase of back thickness and the decrease of panel thickness. Furthermore, the failure mechanism of the ceramic panels, including the cone and radial cracks formation mechanism was analyzed. A “composite beam” model has been established to estimate the local bending stress. The model calculation showed that the local bending stress is related to the panel thickness, back thickness and the panel/back moduli ratio.