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Mechanisms of projectile defeat and ballistic resistance of thin targets impacted by tip-deformable conical projectiles have been discussed in the context of the influence of apex angle of the projectile. Transition in target local failure modes occurred as the projectile apex angle was altered. The effect on projectile deformation and ballistic properties has also been discussed. A brief discussion on projectile deformation mechanism and projectile defeat near ballistic limit velocities with supporting experimental evidence is included. Numerical simulation using ABAQUS/Explicit has been able to effectively predict the projectile deformation and associated target behavior. [ABSTRACT FROM AUTHOR]

This paper focuses on validating a numerical modelling of woven materials subjected to ballistic impact based on experimental data. Studied impact system is a 3D warp interlock fabric (4 layers of angle interlock – through the thickness) and FSP projectile (Fragment Simulating Projectile). Numerical prediction is compared with ballistic tests on data obtained from ultra-rapid camera in two typical impact cases: no perforation and perforation. Effect of deformation rate is investigated by using both mechanical properties of yarn in static and dynamic states for numerical modelling. The numerical model using dynamic parameters shows a better prediction of impact behaviour of the 3D woven fabric than the one using static parameters. [ABSTRACT FROM AUTHOR]

Abstract: The present study describes the ballistic impact behaviour of a high strength metastable near beta Ti alloy, β-CEZ in different microstructural conditions against 7.62 mm armour piercing projectiles. Ballistic trials were carried out on 10 mm thick β-CEZ and Ti–6Al–4V plates clamped with 50 mm thick 7017 Al alloy backing. The ballistic performance of different conditions was evaluated by measuring residual depth of penetration (DOP) in 50 mm thick Al-7017 alloy backing. In the present study, even though the β-CEZ titanium alloy in as-rolled and α + β solution treated + aged conditions had significantly higher strength and hardness compared to conventionally used Ti–6Al–4V, significant improvement in ballistic impact resistance was not observed. Post ballistic microstructural observation of crater cross section showed formation of adiabatic shear bands (ASBs) and ASB induced cracks in all conditions. As-rolled, α + β solution treated and aged conditions of β-CEZ alloy showed more ASBs, ASB induced cracks in comparison to Ti–6Al–4V. The β-solution treated and quenched condition of β-CEZ had less number of ASB and highest residual depth of penetration. In this study the ballistic results are discussed based on the post ballistic microstructural observations. [Copyright &y& Elsevier]

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]

Work done previously on single-ply ballistic resistant fabric systems is now extended to double-ply systems. Experiments were carried out to investigate the impact phenomenon of double-ply systems that consists of Twaron® CT 716 fabric and projectiles of the following nose shapes: hemispherical, flat, ogival (CRH 2.5) and conical (half-angle of 30°). Results obtained revealed that the increase in energy absorption does not necessarily double when the ply number is increased to two. In fact, the ratio of energy absorbed in the double-ply system to that of the single-ply system varies with impact velocity and projectile geometry. At points corresponding to maximum energy absorption, the ratio for all projectile types scatters about an average of 2.1. The amount of deviation from this value depends on the mechanisms that lead to perforation. Failure mechanisms of a double-ply system are similar to those of a single-ply system, but the degree of damage of the impact and distal plies differs. [Copyright &y& Elsevier]