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In order to improve the performance of ceramic composite armor it is essential to know the mechanisms during each phase of the projectile–target interaction and their influence on the penetration resistance. Since the view on the crater zone and the tip of a projectile penetrating a ceramic is rapidly getting obscured by damaged material, a flash X-ray technique has to be applied in order to visualize projectile penetration. For this purpose, usually several flash X-ray tubes are arranged around the target and the radiographs are recorded on film. At EMI a flash X-ray imaging method has been developed, which provides up to eight flash radiographs in one experiment. A multi-anode 450 kV flash X-ray tube is utilized with this method. The radiation transmitted through the target is then detected on a fluorescent screen. The fluorescent screen converts the radiograph into an image in the visible wavelength range, which is photographed by means of a high-speed camera. This technique has been applied to visualize and analyze the penetration of 7.62 mm AP projectiles into three different types of SiC ceramics. Two commercial SiC grades and MICASIC (Metal Infiltrated Carbon derived SiC), a C-SiSiC ceramic developed by DLR, have been studied. The influences, not only of the ceramic but also the backing material, on dwell time and projectile erosion have been studied. Penetration curves have been determined and their relevance to the ballistic resistance is discussed

A systematic study has been performed to gather more detailed experimental information on the equation of state and the Hugoniot elastic limit (HEL) of soda-lime glass as well as the failure front phenomenon. The key innovations of this study comprise experimental as well as analytical aspects. On the one hand, an extensive planar plate impact (PPI) test series has been carried out over a wide range of shock loading stress levels instrumented with two high-speed cameras and laser interferometers (PDV and VISAR). On the other hand, a systematic analysis concept has been developed and evaluated, including a combination of Lagrange diagrams with velocity profile data and a derivation of the equation of state together with an error estimation. Impact velocities ranged from 500 to 3000 m/s resulting in loadings of the soda-lime glass targets between 3.5 and 20.8 GPa. For stress levels between 3.5 and 6.7 GPa two high-speed cameras with 5 Mfps, positioned at the side and rear of the specimens, enabled the observation of shock waves and two different kinds of failure fronts. Therefore, visual information could be gathered not only in the purely elastic regime, but also in the transition region above 4 GPa and at stress levels beyond the HEL. The HEL of the soda-lime glass is determined to $$\left(5.0 \pm 0.2\right) \mathrm{GPa}$$ 5.0 ± 0.2 GPa . For the onset of an internal failure front a minimum longitudinal stress between 3.8 and 3.9 GPa is identified. The evaluated failure front velocities range from 800 to 2100 m/s. From the observed release response a minimum spall strength of 6.7 GPa and release wave velocities between 5740 and 9500 m/s are deduced.

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The ballistic deformation of an ultra-high-molecular-weight (UHMW) polyethylene (PE) composite has been subjected numerically to a multi-layered soft ballistic fabric package modelled upon the body contours of the Global Human Body Models Consortium (GHBMC) human body models M50-P and F05-P. The results of the clothing-body-interaction have been investigated and compared to the behavior of anthropomorphic surrogate models made from ballistic clay. For building the fabric model in donned shape, a single ply of woven fabric material has been converted upon the anthropomorphic body contour by subjecting it to a quasi-deep drawing process. After the fabric deformation, the shaped layer was duplicated 20 times and shifted outwards to build the fabric model, representing a multi-layered soft ballistic fabric package. The results of the ballistic impact simulation show that the response of the human body models (HBMs) is much more compliant than the behavior of the surrogate models. The deformation of the female HBM in terms of penetration depth and diameter of the affected impact region is slightly more severe than the deformation of the male counterpart with respect to identical impact conditions.