Carbon Nanotube Sensor Thread for Structural Health Monitoring of Composites Navy SBIR FY2012.2 Sol No.: Navy SBIR FY2012.2 Topic No.: N122-110 Topic Title: Carbon Nanotube Sensor Thread for Structural Health Monitoring of Composites Proposal No.: N122-110-0900 Firm: General Nano LLC 1776 Mentor Ave. Ste 170 Cincinnati, Ohio 45212 Contact: Joe Sprengard Phone: (513) 309-5947 Web Site: www.generalnanollc.com Abstract: This project will manufacture carbon nanotube(CNT) sensor/tape for use in distributed structural health monitoring(SHM) systems that will be integrated into/onto composite materials to provide damage detection, localization, and characterization. Composite test samples with internally integrated sensors will be built and evaluated to detect/locate multiple damage modes including fiber breakage and delamination. Analytical predictions of the damage magnitude and likely progression of detected flaws over time will be made. Composites with integrated CNT sensor thread/tape will have the following advantages:  Self-Sensing- CNT piezoresistive thread can measure strain/damage, thread impedance decreases at high frequency increasing sensitivity  Increased Strength- Composite strength will increase based on CNT volume fraction  Damage Limiting- CNT thread has high strain to failure and will self-limit damage by absorbing strain energy  Improved Transport- CNT thread has high thermal and electrical conductivity in-plane  No Significant Added Weight or Size- There is almost no added mass of the sensor thread  Modest Cost- Cost for the CNT materials and composites processing is modest  Detection, Localization, and Characterization of Damage- Discerning between a crack and delamination will use a computer algorithm to map the shape of damage  Improved Composites- Can determine failure progression in composites and provide understanding how to reinforce composites Benefits: The use of carbon nanotube thread and tape is a practical method for detecting and quantifying damage in composites. The proposed SHM concept will have industry-wide benefits including improving the safety and maintainability of high cost air vehicles. Interwoven Integration of the sensor material into the ply layers also provides multifunctional advantages. Future military and commercial composite vehicles will have "Nano Inside" to provide safety, durability, condition-based maintenance, and multifunctionality. Return