Coupling Effect of Brittle Projectiles and Ceramic Composite Armor with Different Backings

The mechanical behavior of ceramic composite armor is related to the type of projectile and the material properties of each component under high-speed impact. There exists a coupling effect between the ceramic, backing material, and the projectile during the impact process. Especially for brittle projectiles, there is a clear correlation between the damage evolution and the backing material. This study investigates the mechanical behavior and ballistic response of B4C ceramic composite armor resisting T12A steel projectiles using three different backing materials: Q235 steel, Kevlar, and UHMWPE laminates. Experiments and numerical simulations were conducted. The results show that the Rosin-Rammler distribution model can well describe the mass distribution of fragments of the brittle T12A steel projectile. The protective performance of ceramics against the T12A steel projectile depends on the dwell time, where the Q235 steel backing plate can prolong the interaction time between the projectile and the ceramic, leading to more erosion and fracture of the projectile. The fiber laminate primarily absorbs the remaining kinetic energy of the projectile through its own tensile and shear failure, without causing damage to the projectile. Due to its lower shear strength, the Kevlar laminate is quickly penetrated by the residual projectile, while the UHMWPE laminate undergoes more tensile deformation at the sublayer interface due to its higher tensile strength, absorbing more kinetic energy from the projectile. Furthermore, both the projectile and B4C ceramics fail due to the complex stress caused by compression waves and tensile waves. When the backing plate is Q235 steel, the peak stress inside the projectile is higher, resulting in more severe fragmentation of the projectile. However, the peak stress inside the ceramic remains relatively similar regardless of the different backing materials.