Modeling of the ballistic behavior of gradient design composite armors

Abstract

Abstract The application of gradient design concept in armors offers possibilities in the reduction of weight and cost without significant reduction of ballistic resistance. Experimental results of composite backed plates consisting of layers of ceramic spheres embedded in epoxy showed that a ballistic limit of 3000 ft/s (1000 m/s) can be achieved, as shown in Fig. 1 , without weight penalty compared to solid ceramic tiles. The ceramic sphere facing also provides the feasibility for flexible armor manufacturing. The design of such materials includes a plethora of parameters. In order to develop a precise methodology for the optimization of gradient design composite armors, an improved understanding of the relative significance of the design parameters must be developed. One way to study the relative significance of these parameters is through computational modeling. Computational limitations impose compromises in the modeling of both geometry and material behavior. Two types of models are discussed: (a) an approximate fiber/epoxy two-phase model for the backing; and (b) a damage-based, rate-dependent model for the ceramic spheres embedded in the epoxy. The development of a library of fiber architectures based on the unit cell has been initiated, which will open the possibility of the structural optimization along with simulation of the high velocity impact phenomena of advanced composites.