Enhancing mechanical and thermal properties of epoxy-based polymer matrix composites through hybrid reinforcement with carbon, glass and steel

Abstract This study investigates the mechanical and thermal enhancements achieved in polymer matrix composites (PMCs) through hybrid reinforcement using carbon, glass, and steel fibers. The composites were fabricated via the hand layup technique and evaluated through tensile and flexural testing, as well as thermogravimetric analysis (TGA), differential thermal analysis (DTA), and scanning electron microscopy (SEM). The results demonstrate that hybrid composites exhibit improved microstructural integrity, reduced voids, and enhanced interfacial bonding compared to individual fiber-reinforced composites. TGA and DTA analyses reveal delayed decomposition, lower mass loss rates, and smoother thermal transitions, highlighting superior thermal stability due to hybridization. Mechanical testing shows that carbon–steel composites achieve the highest tensile and flexural strengths, significantly surpassing their single-fiber counterparts. SEM analysis confirms the reduction in defects and superior fiber-matrix interaction in hybrid composites. This study underscores the potential of hybrid reinforcement to optimize the mechanical robustness and thermal efficiency of PMCs, making them ideal for high-performance applications in aerospace, automotive, and structural engineering.