Carbon Nanotube Sheet Reinforced Laminated Composites

Abstract

Laminated composite materials provide high performance, but weak failure modes such as delamination limit their applications. Poor thermal conductivity also makes conventional composites unsuitable to replace metals in hot parts. Fundamentally, the reinforcement architecture of laminated composite materials should be modified to allow composite materials to become more multifunctional (isotropic) to replace metals. Improving the low-strength failure modes and thermal and electrical conductivity of composites would have industry-wide value and significance including increasing the safety and performance of vehicles, wind turbines, aircraft, ships, and motors. In this research, carbon nanotube (CNT) sheet manufactured in the Nanoworld Laboratory at the University of Cincinnati has been integrated into laminated composites for superior interlaminar shear and electrical properties. The CNT sheet was chemically post-processed for better bonding with the carbon fiber laminate. The introduction of CNT sheet does not degrade the inplane properties. In addition to serving as a structural material, the CNT sheet can substantially increase the electrical and thermal conductivity of composites. The CNT sheet integrated with the carbon fiber plies has good electrical conductivity and therefore might be used to replace electrical wires. Therefore, CNT sheet reinforced multifunctional composites can save substantial weight by replacing conventional conductive wires with structural composite material. The multifunctional composites will be a new commercial product and will have uses ranging from aerospace, to wind power, to medicine.