Experimental and numerical investigation of Kevlar and UHMWPE multi-layered armors against ballistic impact

Abstract

This work aims to prepare hybrid composites to evaluate their behavior under ballistic impact experimentally and numerically. Multilayered armors were designed as ceramic/woven fabric reinforced with epoxy/5074 Al-alloy. Silicon carbide (SiC) represents the first layer against the bullet. Aramid fabric (Kevlar) reinforced epoxy (KEV/EPX), or Ultra-high molecular weight polyethylene (UHMWPE) reinforced epoxy (UPE/EPX) represent the intermediate composites, whereas, the back layer was 5074 Al-alloy. In experimental ballistic tests, a 9 mm Full Metal Jacket FMJ bullet was launched at 307 m/s towards armor 30*30 cm2. The Finite Element Method (FEM) is used to simulate the ballistic impact resistance of armor. Results from simulation and experimental testing were compared with ballistic tests and there was a good agreement. The result shows that a SiC+UPE/EPX+Al-alloy and a SiC+KEV/EPX+Al-alloy were able to stop the 9 mm FMJ bullet, and showed that the bullet perforated many layers of armor without penetration. The backface signature (BFS) was also measured. It is within the permissible range. SiC+UPE/EPX+Al-alloy absorbed more energy compared to SiC + KEV/EPX + Al-alloy. The SiC+UPE/EPX+Al-alloy, the ceramic layer absorbed more energy than the UPE/EPX and Al-alloy, reaching 80.5% of the total energy, while in the SiC+KEV/EPX+Al-alloy, the ceramic layer absorbed more energy than the KEV/EPX and Al-alloy, reaching 78.4% of the total energy. UPE/EPX absorbed energy more than KEV/EPX. That reached 19% of the total energy, while KEV/EPX absorbed about 15% of the total energy. The aim of using ansys Autodyn and explicit dynamic is to calculate the amount of kinetic and absorbed energies and to compare the deformation amount with experimental results.