Experimental study on the dependency of the ballistic performance of tiled ceramic/metal targets on inter tile gap width and projectile impact position

Inter tile gaps are points of higher vulnerability of tiled armor systems. For the design of armor systems, the knowledge of this weakness effect is essential. The aim of the study presented here was to understand how the impact position affect's the ballistic performance of tiled adhesively bonded ceramic/metal targets. Furthermore the additional parameters gap width and the stiffness of the used adhesive were also varied.Two hypotheses were tested: (i) the residual velocity (vr) is a function of the impact position, whereby the position with the highest residual velocity (lowest ballistic resistance) is not the center of the gap. (ii) The shape of the function depends on the inter tile gap width and the stiffness of the used adhesive.The impact position of the 7.62 mm tungsten carbide core AP ammunition, the vr and the perforation process were monitored by means of high-speed cameras. Four gap widths and two different adhesive systems (high-strength and high-flexible) were investigated.The results of the ballistic tests have shown a higher residual velocity when the edge of a tile was hit, compared to a centric impact at the gap. Furthermore the ballistic resistance decreased significantly with decreasing adhesive stiffness and increasing gap widths.