DURABLE HYBRID COATINGS

Abstract : The goal of this program is to contribute to the development of the next-generation anti-corrosion and other protective coating systems for USAF aircraft. The initial emphasis of the program was on improvements in NDSU's promising Mg-based primer, which NDSU recently licensed to the major international aircraft coatings manufacturer. Work continued over the last year on improvements in primer binder, additions to NDSU's world-class high-throughput (HT) research and development capabilities that are necessary to work with this class of coatings, and meeting additional Air Force protective coatings needs such as hard surface pretreatments to work with the binder, and development of a methodology for depot-based repair indium tin oxide aircraft canopy coatings. A new effort was initiated late in the year on prognostic measurement techniques to monitor the effectiveness of the magnesium-based primers previously developed. Accomplishments included successful research on a new two component binder system, hybrid organic-inorganic binders, and UV-curable low-VOC binders for Mg-rich primers. The HT approach was instrumental for efficient and effective binder research. Studies of a range of Mg-alloys in the primer have shown that, similar to pure Mg primer, all Mg alloy primers provide cathodic protection to the Al alloy substrate. The composition of the Mg alloy, such as the content of Al and the composition of the third element, can greatly influence performance. Work was largely completed on HT tools needed for development of aerospace coatings: robotic viscous liquid handling, high shear mixing for pigment dispersion, screening methods for characterizing corrosion protection, and HT screening methods for characterizing weatherability.