Low-velocity impact behavior of abaca/epoxy composites with layer variations

Natural fiber-reinforced composites are the focus of extensive research for various engineering applications, particularly in the automotive and aerospace industries, encompassing structural and nonstructural components. When subjected to low-velocity impacts, these components can experience visible and invisible damage, potentially leading to failure. This paper aims to investigate the influence of the number of layers on the low-velocity impact behavior of abaca/epoxy bio-composites. Composites with 4, 6, and 8 layers were fabricated using the hand-layup technique and subjected to impact testing at an energy level of 10.24 J. Key impact responses, including energy-time and force-time histories, were analyzed alongside damage assessment and post-impact surface characteristics, followed by scanning electron microscopy characterization. The experimental results revealed that energy absorption decreased as the number of layers increased, with absorption ratios of 37.89%, 30.27%, and 26.36% for the 4-, 6-, and 8-layer composites, respectively. Interestingly, the composite that sustained more significant damage absorbed more impact energy and vice versa. Furthermore, variations in impact resistance, duration, damage area, and post-impact surface characteristics were observed with the increasing number of layers.