Enhancement of the penetration resistance of materials used in the defense industry is of great interest since such improvements can save human life and can reduce the loss of resources caused by high velocity projectiles penetrating through the walls of important weaponry such as tanks, choppers and armored personnel carriers. Recent experimental studies have shown that polymer coatings can improve the ballistic limit of steel plates. Experimental study of the ballistic properties are expensive but a computational model can make this study more affordable. For accurate modeling of ballistic impact problems, our finite model considers the impact of large deformations, high strain rates and steep hikes in temperatures on the properties of the system.In this thesis we use finite element analysis to study the ballistic properties of steel-polyurea laminate. The FEM simulations are conducted in Abaqus and includes a projectile impacting a target. We use 4340 steel plate with and without polyurea coating as the target. The material behavior of 4340 steel target plate is captured by Mie-Grüneisen and Johnson-Cook models and Mooney-Rivlin model is used to model the behavior of polyurea and adhesive. The projectile is assumed to be rigid. Various scenarios involving different types of projectiles and different positions of the polyurea are studied.After careful examination of the results, it is concluded that failure occurs in two different modes (petalling and shearing). The failure mode depends on impact velocities. It is also observed that polyurea coating improves the penetration resistance and the energy absorption rate of 4340 steel plate. Finally it is noted that the shape of the projectile has its impact on the material failure and the effect of polyurea.
