DACCO SCI, INC., (DSI) proposes a Phase I SBIR program to use an electrochemical impedance spectroscopy (EIS)-based corrosion sensor to monitor the integrity of an adhesive bondline and correlate sensor measurements with mechanical properties. Using this sensor approach to detect moisture intrusion into a bondline will give advance warning of potential environmentally induced bondline deterioration. Corrective action can then be taken prior to permanent disruption of the bondline. Delaminations and kissing unbonds may also be detectable. This monitoring technology could eventually be used as a standard tool in the suite of nondestructive evaluation (NDE) methods for evaluating the integrity of adhesive bond. Because embedded sensors are not required, both existing and future structures could be inspected and monitored. Increased confidence and reliability of bonded structures would accrue. POTENTIAL COMMERCIAL APPLICATIONS Reliability of bonded structures will increase as a result of this health monitoring. Readiness and safety are also benefits to improved health monitoring. Extending the technology to composite materials is anticipated to be very feasible. Adhesively bonded repair patches (metal or compos-ite) on aging aircraft are one important application. Composite-reinforced infrastructure (e.g., bridge supports) is another application of interest. Other potential applications include storage tanks, pipelines, and weapon systems and components
