Experimental study on protective performance of ACF sandwich composites with different configurations in high-velocity impact

The design of impact protective gear is crucial to human safety against high-velocity impacts from explosions. The rigid and flexible foam sandwich composites with ACF foam as the core and fiber-reinforced composite panels or high-performance fabrics as front/back panel materials were selected in this study. Hopkinson pressure bar experiment was conducted to assess the dynamic response, energy absorption, and dissipation rates of two types of composites in high-velocity impact. The effects of the number of structural layers, front/back panel thickness gradient, and panel material type on the protective performance were examined. The results demonstrated that the three-layer structure presented better protection and increased the energy absorption rate by 5% compared to the five-layer configuration in rigid and flexible composites. Thickness gradient and material type of panels had minimal impact on the protective performance of rigid composites compared to structural layers. Adding Kevlar layers to flexible composites improved protection, with 95.89% energy absorption and 31.82% energy dissipation at a core thickness of 8 mm. These insights guide the development of advanced impact protection materials to elevate personnel safety against high-velocity impacts.