Multifunctional Carbon Nanotube-Based Sensors for Damage Detection and Self Healing in Structural Composites

During the past year of the research program focusing on developing composites with damage sensing and self-healing functionalities based on carbon nanotubes, improvements to the state-of-the-art in nanocomposite processing have been made. In order to accommodate the processing of thick-section composites, an alternative approach to the traditional calandering method of carbon nanotube dispersion has been developed. A fiber sizing agent containing multiwalled carbon nanotubes was used in the processing of conductive E-glass fabric composites, which were demonstrated to undergo measurable, non-reversible changes in resistivity during the accumulation of damage under quasi-static loading scenarios. These conductively-modified composites possess the potential to sense damage under fatigue tensile and dynamic compressive and impact loadings. A review article describing the design, processing and resultant mechanical, electrical and thermal properties of nanotube-based composites has been published.