In this study, ballistic behavior of multi-layered ceramic armors under high velocity impact is studied numerically. The model consists of 2D-axisymmetric Lagrangian approach with Johnson–Holmquist constitutive model for alumina ceramic tiles, Mie–Gruneisen equation of state for polymeric interlayers, and Johnson–Cook constitutive relation for Armor Piercing (AP) projectile. The finite element results obtained from various armor layups show the potentiality of multi-layered ceramic armor in extending conoid fracture through the ceramic layers, thus leading to the increase in the armor performance. It is illustrated that besides ceramic armor layup, interlayers of ceramic tiles have a significant role in increasing the armor performance. Finally, the effect of different polymeric interlayers on ballistic performance of multi-layered ceramic armors against AP projectile is investigated. In order to measure the ballistic performance of the armors, various criteria are introduced. Depth of penetration of the projectile in the armor, residual velocity of the projectile, time duration in which the projectile is engaged inside the armor, projectile tip erosion during impact, and interaction volume ratio are some of these criteria. The study indicates that armor layup with thin front ceramic tiles backed by thicker tiles shows better conoid fracture extension and often better ballistic performance. Furthermore, among the polymeric interlayers used between the ceramic tiles, polystyrene causes the best and nylon causes the worst ballistic performance in the armor.

Proper combination of fiber reinforced composite and metal is a novel concept that it caused the advent of fiber‐metal laminates. This study reports the impact response of 3D‐woven glass fiber fabric composite cores experimentally, and it describes the effect of silica and graphene nanoparticles addition on energy absorption behavior of laminated fiber‐metal composites. The composites are manufactured by VARTM method with 71% fiber volume fraction. The low velocity impact tests are performed with drop‐weight impact test machine with various impact energies. The results show higher impact performance of plain‐weave samples compared with 3D‐woven glass fiber fabrics under different impact energies. The 3D‐woven glass fiber fabrics are preferred in case of using samples with lower weights. POLYM. COMPOS., 39:3528–3536, 2018. © 2017 Society of Plastics Engineers

This study reports experimental and numerical behaviors of both dry and silicon-coated twill-weave Kevlar fabrics under low-velocity impact. Initially, the fabrics are augmented in silicon aqueous suspension with various particle concentrations, and then, increase in the weight and friction coefficient are studied. The low-velocity impact test results show that the best particle concentration to meet the mentioned requirements is about 10 wt%. The experiments indicate high-impact resistance of the target by increase in the number of fabric plies. It is found that silicon-coated fabrics under drop-weight test show more time duration of impact and better performance than dry fabrics. Furthermore, the tests show that in the dry fabrics, broader region stretches due to impact, while in silicon-coated fabrics, the damage is limited to the impact point. The numerical simulation is performed for the coated fabric, and the effect of fabric augmentation with silicon is introduced as yarn friction. The numerical results are in good agreement with the experimental results.

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