Multifunctional, Low-Cost, Inorganic Seal Coatings for Radomes

Barrier coatings to prevent moisture ingress into radome structures of advanced missile systems are a critical need for the Navy. Ingress of moisture during missile storage can degrade the critical sensor and guidance electronic components housed within the missile radome. The US Navy is developing missiles targeted for varying flight conditions which utilize many radome materials. A versatile coating solution is desired that address sealing of polymer and ceramic radomes adequately over the long-term. Inorganic coatings are preferred for this application due to their superior barrier properties, chemical resistance, and thermal performance. However, deposition of suitable inorganic coatings with adequate coverage for barrier performance is a significant challenge. A thin barrier coating based on aluminum phosphate composition is being proposed under this Phase I effort. The coating is derived using a solution-derived process which is low-cost and easy-to-apply and provides excellent adhesion to both polymer and ceramic substrates. Phase I work will include study of deposition, curing, and performance testing for both classes of substrates. The work will be conducted in close collaboration with a defense prime contractor. Phase II effort will be devoted toward prototype demonstration and further optimization of coating properties and development of roadmap for technology transition.