Ballistic reliability study on SiC/UHMWPE composite armor against armor-piercing bullet

The ballistic reliability of composite armors is significantly affected by the random material properties. In this paper, the mosaic SiC ceramics/ultra high molecular weight polyethylene (UHMWPE) composite targets with bonding adhesives are tested near the limit ballistic penetration conditions. The uncertain material and adhesive properties led to complete penetration and partial penetration at bullet initial velocity of 776 m/s and 791 m/s, respectively, and a contrary tendency is also observed in the tests between the bulging deformation and the minimum target thickness of back plate. A state function of penetration for reliability evaluation is formulated based on a validated numerical model. Results from sensitivity analysis indicate that twelve uncertain material parameters are strongly sensitive to the penetration state. Then, the ballistic reliability under the test velocities is obtained by both Monte Carlo method and design point method. Finally, an optimization problem with a probability constraint is established in order to achieve a minimum deformation. The results show that the bulging deformation and the value of penetration state function vary with the adhesive strengths oppositely. Therefore, the adhesive strengths are designed to control the contradiction between the deformation and the minimum target thickness. It is significant to recognize the uncertain properties of composite armors and to improve the ballistic performance against armor-piercing bullet.