![]() 1000 m/s was identified for the unstressed target, increasing to approx. In-situ diagnostics were unsuccessful in aiding the identification of interface defeat, necessitating a reliance on post-mortem assessment. Four targets of each configuration, referred to as slip-fit, moderate pre-stress, and high pre-stress, were subject to ballistic testing with hemispherical-nose, tungsten heavy alloy long rod projectiles to determine the interface defeat transition velocity. The induced radial stresses, ranging from 0 to 900 MPa, were measured via neutron diffraction and verified by comparison with numerical calculations. Thus, the armour is equivalent to the third level of protective ballistic limits in the National Institute of Justice (NIJ) standards.A series of bare silicon carbide ceramic armour disks were manufactured with high-strength steel containment to induce varying magnitudes of radial pre-stress. On the other hand, this armour meets the ballistic threats under 623 m/s of 15 mm ± 3 mm target thickness and 837.5 m/s of 25 mm ± 2.mm. This body armour is one of the most economical armour products, in which common materials are used in its production, particularly to reduce the amount of Kevlar, and this could further lead to a decrease in its production cost. Hence, the results present a high resistant impact for pairs from the panels with total thickness arrived to 15 mm ± 3 mm. Targets geometry plays a major role in increasing the impact response. A limited delamination was generated under multiple shots. The range of temperatures was between 20 o C and 70 o C. the range of 50% ± 20%, whereas, reduction of resistance results in the increase of temperature. The targets are improved in term of the impact response with the increase in the relative humidity, i.e. ![]() The results of these experiments indicated that the maximum ballistic limit validated at impact speed is in the range of 250 m/s to 656.8 m/s for the second protection level. In order to achieve the goal of the research, several experiments were conducted with the aim to estimate the ballistic limit, maximum energy absorption, composite failure mode, life time rupture, target geometry, and environmental effect. The target was shot using gas gun machine that is supported by camera hardware to capture the projectile speed. This composite is subjected to high impact loading. The aim of this study was to develop a solid body armour that meets the specific requirements of ballistic resistance. For this purpose, laminate composite material was developed from Kevlar 29-ramie-unsaturated polyester resin. This study was conducted for the development of the green protection garments. Finally, the results revealed that the associated data with SPH confirm the modified analytic model at higher accuracy than the Florence's analytic model. As such, it can be observed that, at the same thickness and areal density, the ceramic target has its efficiency enhanced with increasing ceramic thickness and decreasing the support layer thickness. These findings indicate enhanced levels of target energy absorption and the required energy for bending and tensioning the target. Results indicated that, with increasing initial velocity and ceramic thickness and decreasing support layer thickness, the radius of ceramic cone decreases this ends up increasing residual velocity of the projectile and penetration time and extending the area across which the pressure is distributed. The phenomenon of impact onto ceramic/aluminum composites were modeled using smoothed particle hydrodynamics (SPH) implemented utilizing ABAQUS Software. In order to investigate and evaluate accuracy of the presented analytic model, obtained results were compared against the results of the Florence's analytic model and also against numerical modeling results. In the present research, a modified model based on radius of ceramic cone was presented for ceramic/aluminum targets. Radius of ceramic cone can largely contribute into final solution of analytic models of penetration into ceramic/metal targets.
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