Comparative Mechanical Behavior of Epoxy Composites with Different Fiber Reinforcements and Fiber/Resin Ratios for Prosthetic Applications

Abstract

This study investigates the mechanical properties of hybrid composites made from epoxy resin, coconut shell (CS), and groundnut shell (GNS) for potential applications in prosthetic sockets. The aim was to evaluate how varying the fiber content of CS and GNS impacts the compressive strength, flexural strength, and impact strength of these composites, providing insight into their suitability for use in prosthetic devices. The composites were fabricated with different fiber-to-resin ratios: 92% epoxy/5% CS/4% GNS, 90% epoxy/5% CS/5% GNS, 88% epoxy/6% CS/6% GNS, 86% epoxy/7% CS/7% GNS, and 84% epoxy/8% CS/8% GNS. Standard mechanical tests, including compression, flexure, and impact testing, were performed to evaluate the mechanical properties. The results revealed that the 88% epoxy/6% CS/6% GNS composite exhibited the highest compression strength (55.4 N/mm²) and flexural strength (55.4 N/mm²), while the impact strength was highest in the 84% epoxy/8% CS/8% GNS composite (0.42). Conversely, composites with higher epoxy content and lower reinforcement showed reduced impact strength but improved stiffness. These findings contribute to the understanding of the mechanical behavior of natural fiber-reinforced composites, highlighting the potential for developing sustainable, high-performance materials for prosthetic socket fabrication. The study supports the use of renewable materials in the medical industry, aligning with national efforts to promote sustainable technologies and reduce reliance on synthetic materials, ultimately contributing to both environmental sustainability and the advancement of prosthetic technologies.