Influence of impact location and ceramic degradation on projectile defeat mechanisms in rod-reinforced ceramic-metal armor

Add-on armor systems require lightweight designs that efficiently dissipate energy under ballistic impact. This study examines cast architected ceramic-metal composites reinforced with Al₂O₃ and SiC rods embedded in an aluminum matrix, focusing on the interaction between manufacturing-induced degradation, structural architecture, and impact response. The results show that the casting process significantly reduces ceramic properties, with a tensile strength decrease of 46% for SiC and 23% for Al₂O₃, which may contribute to the observed differences in ballistic response. Ballistic tests combined with X-ray diagnostics indicate that impact location influences the main projectile failure mechanism. Inter-rod impacts appeared to promote lateral loading and fragmentation of tungsten-carbide cores, resulting in lower residual velocities than those observed with impacts on the central rod. All configurations stopped the 7.62×54R B32 projectile, while complete penetration occurred with the 7.62×51 AP8 projectile. Numerical simulations matched the residual velocity and back-face deformation within 5% and 15%, respectively, for selected cases. The combined experimental and numerical framework provides mechanistic insight into the process-structure-performance relationship in cast-rod-reinforced cermet systems. The results suggest a transition between limited and extensive projectile-core fragmentation in the investigated configurations, which appears to be influenced by impact location and the post-casting condition of the ceramic phase.