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The use of lightweight systems is essential for future combat systems. More and more steel structures are replaced by composite structures. This also influences the vulnerability of the platform. A finite element material model is created in Autodyn of the carbon fiber reinforced plastic (CFRP) AS4/3501 in order to predict both the residual velocity and the damage after ballistic impacts. This paper will explain the used input parameters, of which most are obtained from material tests. Furthermore, results are shown from ballistic impact experiments and simulations, followed by analysis of the residual damage in both the experiments and the simulations. The paper will show that the simulated residual velocities are consistent with velocities measured in experiments. Furthermore, the predicted residual damage is in the same order of magnitude as the observed residual damage.

Now that an industrial-scale low-cost production route for ballistic-grade titanium is within reach, the potential use of titanium armour could depend on a solution for the spalling of high strength titanium. This paper addresses a titanium based metal laminate as being a possible solution for the use of titanium in armour concepts. Autodyn-2D is used in a numerical study to qualify possible configurations. This so-called experiment design resulted in a preliminary experimental program and will be presented. Another question to be addressed in this paper is whether magnesium alloys can be used as armour material. Despite current limitations on available magnesium alloys useful for armour applications, its potential ballistic performance is shown by experimental results of armour configurations with magnesium alloys against a limited number of threats

Operational requirements for vehicles result in a constant trade-off between protection and mobility. Mobility limits the weight of the armoured vehicle despite the fact that it needs protection against several threats. In metallic armour systems the hardest material is normally used at the outside of the vehicle. This paper shows that in some situations it is beneficial to use the harder material at the inside of an armour system. Experiments are done with three types of ammunition from level 1 and 2 of the STANAG 4569 on several metallic armour systems of steel and aluminium. Furthermore, numerical simulations are performed to help understand the phenomena involved in these impact situations. The stripping of the jacket off the projectile core seems to be an important aspect when an armour system is designed out of two different materials. It can be beneficial to place the ‘soft’ material in front of the ‘hard’ material.

WC-based ceramic metal composites (cermets) are of great importance in both armor and munition design due to the combination of properties imparted by the presence of two different phases. WC-Co cermets are of interest in this area due to the hardness and strength imparted by the WC phase while the cementing Co matrix acts to increase plasticity and toughness. Here the dynamic response of G13 WC-Co manufactured by Kennametal Engineered Products B.V. was studied via a series of plate impact experiments involving both longitudinal and lateral gauges, which allowed determination of the Us - Up relationship, measurement of a Hugoniot elastic limit of 3.3±0.2 GPa, measurement of a spall strength of 4.38 GPa, and an investigation of the stress dependence of shear strength in such a strong material. © 2009 American Institute of Physics.

High-speed photography has been used to investigate the dynamic behaviour of similar grades of WC-Co hardmetals during ballistic impacts with velocities in the range of 28-484. m/s. Key features of the failure of similar grades of WC-Co materials during complimentary impacts have been observed and discussed. In particular, fast moving fragments were observed to emanate from the point of impact and flow radially across the target's surface analogous to the processes of interface defeat. Further, as the velocity of impact was increased a non-linear increase in the indentation depth was observed that corresponded with an apparent onset of trans-granular fracture in the WC crystallites. Comparisons with ANSYS AUTODYN™ simulations were made and good correlation has been established between the measured inelastic deformation and computations using a simple strain-hardening model. © 2010 Elsevier B.V.

The use of lightweight composite armour concepts is essential for the protection of future combat systems, both vehicles and personal. The design of such armour systems is challenging due to the complex material behaviour. Finite element simulations can be used to help understand the important design parameters. A material model of Dyneema, a high performance poly-ethylene (HPPE) composite, has been developed with the use of Autodyn. This model is used in several projectile-target configurations and the results are compared to experiments. The simulated residual velocities correspond to the experimental velocities. Also the penetration depths into the target correspond to the experiments when the projectile is stopped. Comparison of the deformation of the backface of the target is difficult due to the long run times necessary to reach the final deformation. However, the first findings are very promising.