Energy Absorption and Ballistic Performance of Epoxy Composite Reinforced with Arapaima Scales

Abstract

Arapaima scales possess a hierarchical structure capable of absorbing a considerable amount of energy before fracture. These natural dermal armors present significant potential in the sustainable development of cost-effective composites. This work aimed, for the first time, to analyze the impact resistance and ballistic performance of arapaima scale-reinforced epoxy composites and their potential application in multilayered armor systems (MAS). Composite plates were prepared with 20%, 30%, and 40 vol% of arapaima scales. Composite specimens were subjected to notched Izod impact and residual velocity stand-alone tests and their MAS through backface signature (BFS) tests, with their fracture surfaces studied using SEM. The Izod tests confirmed the effect of scales’ volume fraction on the energy absorbed by the composites, showing an increase with volume fraction. Residual velocity tests showed that composites with 30 vol% of scales resulted in the most significant improvement in absorbed energy. All MAS formulations presented BFS depths lower than the trauma limit specified by the NIJ standard. Fractographic analysis showed that the scales’ toughening mechanisms improved the composites’ energy absorption capacity. The experimental results substantiate the potential use of arapaima scales as a reinforcement agent in polymeric composites, with 30 vol% being the optimal volume fraction for energy-absorbing applications.

Ballistic Performance, Thermal and Chemical Characterization of Ubim Fiber (Geonoma baculifera) Reinforced Epoxy Matrix Composites

“…On the other hand, composites reinforced with guaruman fibers [78], hemp fibers [25], and arapaima scales [76] exhibited inferior ballistic performance when compared to epoxy/ubim composites.…”

Numerical simulation of composite materials with sisal and glass fibers for ballistic impact resistance

“…The results have shown that the difference in velocity and angle significantly affects the energy absorption capacity of the composites [48,49]. Additionally, the orientation of the fibers in the impact direction has been found to improve the impact energy absorption and overall mechanical response of the composites [50,51]. Finite element simulations have been used to evaluate the behavior of composite panels under ballistic impacts, providing insights into the number of layers broken, delamination effects, and deformation patterns [20].…”