Bionic stab-resistant body armor based on triangular pyramid structure

A stab-resistant substrate was designed and realized with a triangular pyramidal structure inspired by the biological armor model in the nature. Through numerical simulation and experimental testing of a knife impacting a substrate, the stab-resistant behavior and dynamic response mechanisms were studied. It was found the stab-resistant performance on the triangular pyramidal substrate was better than the flat plate. The surface of the triangular pyramidal substrate effectively avoided the normal force generated from impacting due to a significant dispersion effect on the tilted pyramid structure. The substrate tended to be inclined and the stress of the backing material was inhomogeneous, absorbing more energy. Much of the deformation energy and others, such as heat and light energy, were caused due to intensive collision between the knife and the substrate, all of which leading to a rapid drop of the knife kinetic energy. The substrate with higher tilted angle led to improved energy dispersion, as well as larger area density. The optimal design parameters were achieved with the knife impacting tests, of which the tilted angle was 22.5 and thickness 1.2 mm. The stab-resistant layer made of the titanium alloy through compression molding consisted of the optimal design parameters. A new riveting method was used to perform the total layer, which passed the GA 68-2008 National Standard. The overall areal density of the stab-resistant layer was 5.85 kg/m², which was 45% lower than a commonly used stab-resistant layer. The method provided may enlighten the future design and manufacturing of stab-resistant clothing. The full version of this abstract will appear in Defence Technology in 2020.