Mechanical and thermal performance of epoxy hybrid composites reinforced with carbon, Kevlar, and zirconia

Abstract In the present work, Epoxy hybrid composites reinforced with carbon fibers, Kevlar fibers, and zirconia (ZrO 2 ) nanoparticles were fabricated using the hand lay-up technique and evaluated for mechanical and thermal performance. Five hybrid compositions with varying Kevlar and carbon fiber contents and a constant ZrO 2 loading of 7.5 wt% were investigated. Among the studied compositions, the composite containing 40 wt% Kevlar and 10 wt% carbon exhibited the best overall performance, showing superior tensile, flexural, and compressive strengths compared to other compositions. Thermal analysis revealed improved thermal stability of the optimized hybrid composite, with delayed degradation and a more gradual mass-loss behavior relative to neat epoxy and other hybrid systems. The enhanced performance is attributed to the influence of carbon fibers providing stiffness, Kevlar fibers improving toughness, and zirconia nanoparticles enhancing interfacial bonding and thermal resistance. These results demonstrated the effectiveness of hybrid reinforcement in improving the performance of epoxy composites.