Application of metaheuristics to evaluate energy absorption and damage tolerance in GFRP-epoxy nanocomposite laminates

Fiber-reinforced composite laminates are used extensively in various industries due to their lightweight and high-strength properties. However, the poor damage tolerance capabilities of the matrix pose a significant challenge to their efficient utilization. To address this, the present research aims to enhance the damage tolerance, resistance to failure, and strength of fiber-reinforced composite laminates by reinforcing nanosilica as secondary reinforcement. Quasi-static indentation experiments were conducted on Glass Fiber Reinforced Polymer (GFRP)/epoxy laminates reinforced with nanosilica at varying concentrations to evaluate their damage properties and failure characteristics. The performance of laminates was also evaluated under different temperatures. The results showed that traditional composites suffered from macro-damage mechanisms such as brittle failure of the epoxy matrix, ply delamination, fiber pullout, and fracture. In contrast, nanosilica-reinforced composites exhibited enhanced fiber-matrix adhesion, numerous micro-cracks, and higher fiber-matrix damage due to the generation and propagation of primary microcracks in the matrix system. The optimal concentration of nanosilica further enhanced the phenomenon of crack deflection and bowing mechanisms and facilitated load transfer from the matrix to primary reinforcement fibers. These appreciable enhancements in properties and damage tolerance demonstrate the potential of nanosilica-reinforced composites as a substitute for conventional polymer composites. Furthermore, this research investigated the effects of nanosilica reinforcement, angle of contact, and temperature on the energy absorption characteristics and damage tolerance of the laminates using the Zebra Optimization Algorithm (ZOA).