Multifunctional Fibers for Self Diagnosis of Composite Structures

Triton's team proposes to adapt an existing in-situ nondestructive health monitoring systems (SmartFiberO) for a new class of high performance polymer composites that will evaluate tensile, compressive and flexure stress inducing test geometries. Triton'sSmartFiberO system, which uses changes in electrical properties of in-situ structural fibers to measure structural integrity, has been demonstrated in ceramic composites. The proposed system can be seamlessly integrated into current compositemanufacturer's process specifications. Triton's team will evaluate the three stress inducing test geometries for failure modes and mechanisms. The identified modes will be related to the data obtained from the state of the technology nondestructivetesting to understand the evolution and criticality of the damage induced from the various modes of failure. The monitoring system will be utilized to determine the criticality of damage to the composite geometry and failure mechanisms. Calibration ofthe system will allow predictive tools for the estimation of damage criticality of the composites, by relating the results to physical network models and mechanical models of the damage in composites. The implementation of advanced composites into DoD andNASA application requires a reliable tool for inspecting structures for performance and life limiting microstructural damage and defects formed both in manufacture and while in use or storage. The broad range of composite structures that are alreadyqualified and fielded requires that an inspection method be compatible with current systems, while new designs are using more complex and new materials for which no inspection techniques currently exist. A reliable inspection tool will not only reducetotal life cycle costs and reduce down time for inspection of current systems, but will allow the insertion of new composite materials that promise to improve performance and reduce cost in many DoD, NASA and commercial applications.