Thermally Remendable Composite Structures with Resistive Heating Network of Carbon Fibers

ABSTRACT: Carbon fiber-reinforced composites undergo subcritical damage well before final failure. A self-healing composite material is proposed that will autonomously sense and repair localized damage in composite structures. Healing is accomplished via two main components. The first component is a thermally remendable polymer matrix that is integrated into the structural carbon fiber composite and has the ability to be healed with the application of heat. The second component is an addressable conducting network (ACN) that will both sense resistance changes due to damage in carbon fiber composites as well as deliver current for resistive heating to addressable locations within the composite. A health management system will continuously monitor the health of the structural composite and will determine the location and extent of detected damage as well as the potential for autonomous repair. BENEFIT: The proposed technology provides a solution to the serious problem of detecting and repairing impact, delamination and microcracking damage in aircraft and vehicles. Currently, such damage can go undetected resulting in a compromised structure that can endanger personnel and reduce mission readiness. The software developed in conjunction with the novel structural designs developed within this program will allow maintenance personnel to continuously monitor the health of composite structures. When damage is detected, a healing procedure can be initiated to rapidly restore the integrity of the structure. Commercial and military aircraft are increasingly constructed from carbon fiber, and the proposed monitoring and healing technology will reduce maintenance cost and increase service lifetimes of composite air frames. The ability to monitor the health as well as address structural issues remotely will provide an unprecedented ability to maintain inaccessible composite structures such as satellite and space vehicles.