Mechanical characterization of glass/epoxy polymer composites sprayed with vapor grown carbon nano fibers

Vapor grown carbon nano fibers (VGCNF) have been considered as promising means for enhancing mechanical properties of advanced composites including high strength, stiffness, and improved toughness. This paper reports the processing of a glass fiber reinforced epoxy composite with carbon nano fibers integration through spraying methodology and examines the reinforcement potential on tensile and compression strength. Spraying the glass fiber weave with carbon nano fibers before infusion and processing modification led to enhancement of the interface properties. A maximum of 26% increase in tensile strength and 11% in compressive strength over control samples was observed on several wt% additions of carbon nano fibers i.e dispersing the CNF solution on glass fabric, and evaporating the solvent such that only nano fibers remain on pre-form followed by VARTM. SEM of fractured surfaces revealed improved primary fiber-matrix adhesion and indications of CNF-induced matrix toughening due to the presence of CNFs. It also revealed relatively less damage in the tested fracture surfaces of the nano phased composites in terms of matrix failure, fiber breakage and matrix-fiber de-bonding, compared to the neat system.