Experimental study on the protective performance of bulletproof plate and padding materials under ballistic impact

Abstract With the upgrading of protective equipment, the penetration ability of bullets into protective equipment is reduced, and the problem of non-penetrating brain injury caused by bullet impact becomes prominent, but related experiment is still rare. Therefore, this study establishes a human head surrogate model with anatomical structure, and then an experimental study on the dynamic response of cranial model protected by bulletproof plate impacted by 5.56 mm rifle bullet was conducted. The influence of bulletproof plate and padding material (type and density) on the head protection performance is analyzed. The results show that the acceleration of the front of the skull is reduced by 600 times with the protection of pad. At the density of 30 kg/m3, the protective effect of EVA (Ethylene-Vinyl Acetate copolymer) foam is better than that of EPP (Expanded polypropylene), the peak acceleration at the front of the skull is reduced by 36%. As the density of EVA foam increases, the acceleration of skull and the peak intracranial pressure increase, which can be judged that the brain injury would be aggravated according to the existing injury criteria. The study has important guiding significance for the design of protective equipment and the mechanism of cranial injury.