The Effect of Nano-Iron Oxide Particle on Mechanical Properties of Glass Fiber Reinforced Composites

This investigation was conducted to see the effects of α-Fe2O3 (iron oxide) nanoparticles on the mechanical and thermal performance of nanocomposites and glass fiber-reinforced composites (GFRC). Nano iron oxide added epoxy samples with 0.5–4.0 wt.% nanoparticles were produced to determine the optimum reinforcement level. Tensile testing of nanocomposites epoxy specimens showed that 0.5 wt.% addition delivered the best results, with a 13.62% rise in tensile strength, a 37.94% increase in toughness, and a 5.9% improvement in the glass transition point compared to the unmodified epoxy reference. Thermal characterization via differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) measurements indicated improved thermal stability at low nanoparticle content, while FTIR analysis confirmed physical rather than chemical interactions between nanoparticles and the matrix. Using the optimal nanoparticle content, specimens were fabricated via vacuum-assisted hand lay-up and tested under tensile and bending conditions. Compared to unfilled GFRC, the nano-reinforced laminates showed a 21.43% increase in ultimate tensile strength, a 23.08% higher toughness, and a 22.3% greater elongation at break, with negligible change in elastic modulus. In contrast, flexural strength and modulus decreased by 20.54% and 26.7%, respectively, likely due to reduced compressive resistance and particle clustering. SEM fracture analysis revealed stronger fiber–matrix adhesion under tensile loading but more brittle failure modes in bending. The findings demonstrate that low α-Fe2O3 nanoparticle content can significantly improve the tensile performance of epoxy-based composites, though careful control of dispersion is essential to prevent flexural property losses.