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Abstract: This paper presents a ballistic impact simulation of an armour-piercing projectile in hybrid ceramic/fiber reinforced composite armour. The armour is composed by an alumina plate and an ultra high molecular weight polyethylene composite. In order to model the armour behavior three different constitutive models were formulated and implemented into ABAQUS/Explicit finite element code. Comparisons between numerical predictions and experimental results in terms of damage shape/extent and V50 are also presented and discussed in the paper. [Copyright &y& Elsevier]

Abstract: In this paper, based on LS-Dyna code, a new finite element (FE) simulation of the ballistic perforation of the ceramic/composite targets, which impacted by cylindrical tungsten projectiles, has been presented. Research on this method has been conducted by a few research groups in recent years. The ceramic material, which is the front plate, has been made of Alumina 99.5% and composite back-up plate composed of Twaron fibers. The 2-dimensional (2D), axi-symmetric, dynamic-explicit, Lagrangian model has been considered in this simulation. The Johnson–Cook, Johnson–Holmquist and Composite-Damage materials behaviors have been used for projectile, ceramic and composite materials respectively. The brittle fracture and fragmentation of ceramic conoid, the failure criteria based on fracture of fibers or matrixes of composite materials and erosion or flattening of projectile during perforation have been considered. The residual velocity and perforation time has been obtained and compared with the available analytical models. The results show that when the ceramic is impacted by a projectile, a fragmented ceramic conoid breaks from ceramic tile and the semi-angle of ceramic conoid with increasing initial velocity decreases. Furthermore, the dishing of composite layers at high impact velocities and the delamination of layers near the ballistic limit velocity decrease. [Copyright &y& Elsevier]

Abstract: In this research an armor material with constant thickness has been studied. The armor consists of two layers: one is a boron carbide ceramic and the other is Kevlar 49 fiber composite material. By using Ansys/Lsdyna software, the ballistic limit velocity of this armor has been obtained and the Heterington equation (optimum thickness of layers) has been verified for constant thickness of the armor. In this research, mechanical properties of Kevlar 49 under different strain rates are utilized and showed that consideration of the strain rate is very important for the simulation of penetration process. Results from the model have confirmed the validity of the Chocron–Galvez analytical model. Moreover, the projectile velocity prediction, especially at high velocity, shows a good agreement with numerical simulations. Finally, normal and oblique impacts of projectile to armor have been simulated and compared. The results show that the ballistic limit velocity of armor increases under oblique impact conditions. [Copyright &y& Elsevier]

Abstract: This paper examines the penetration and perforation of fibre-reinforced plastic (FRP) laminates struck by rigid projectiles with different nose shapes within a wide range of impact conditions using ABAQUS/Explicit code. It is assumed that the FRP laminate target response can be represented by a velocity dependent forcing function which eliminates discretizing the target as well as the need for a complex contact algorithm. The forcing function is then applied to the surface of the projectiles as boundary conditions in the numerical model. With this combined analytical and computational technique we can obtain the depth of penetration, residual velocity, ballistic limit, transient response in terms of time-histories of displacement/penetration, velocity and deceleration of the projectile. It is shown that the model predictions are in good correlation with available experimental data. [Copyright &y& Elsevier]