Compressive and flexural behavior of ultra-high-modulus polyethylene fiber and carbon fiber hybrid composites

Abstract With epoxy resin as the matrix, five types of unidirectional composites—an ultra-high-modulus polyethylene fiber (UHMPE) reinforced composite, a carbon-fiber-reinforced composite and three UHMPE carbon hybrid composites with different hybrid ratios—were fabricated. The compressive and flexural behavior of these composites was investigated and the failure modes were examined by scanning electron microscopy. The results show that the incorporation of a moderate amount of carbon fiber into a UHMPE-fiber-reinforced composite greatly improves the compressive strength, flexural modulus and flexural strength while the addition of a small amount of UHMPE fiber into a carbon-fiber-reinforced composite remarkably enhances the ductility with only a small decrease in the compressive strength. The mechanisms behind the enhancement of mechanical performance are discussed.