A HIGH ADHERENCE CERAMIC COATING FOR EROSION RESISTANT APPLICATIONS

WOOD AND RESIN MATRIX COMPOSITE PROPELLERS FOR UNMANNED AIR VEHICLES SUFFER UNACCEPTABLE EROSION DAMAGE DUE TO LIQUID AND SOLID IMPACT. POLYMERIC PROTECTIVE COATINGS ARE INEFFECTIVE IN SOLID PARTICLE ENVIRONMENTS. THE BROAD DAMAGE AREA OF PROPELLERS MAKES METALLIC PROTECTIVE COATINGS, SUCH AS HAVE BEEN DEVELOPED FOR HELICOPTER BLADES, UNACCEPTABLE FROM A WEIGHT PENALTY. CONVENTIONAL CERAMIC COATINGS HAVE DEMONSTRATED EXCELLENT EROSION RESISTANCE, BUT HAVE BEEN ERRATIC IN PERFORMANCE, DIFFICULT TO APPLY TO COMPLEX SURFACES, AND HAVE POOR ADHERENCE PROPERTIES. A SOL-GEL-DERIVED CERAMIC COATING OFFERS TAILORABLE POROSITY CHARACTERISTICS WHICH SHOULD OPTIMIZE EROSION AND TOUGHNESS PROPERTIES. THE SOL-GEL PROCESS LENDS ITSELF TO APPLICATIONS TO COMPLEX SURFACES. A NOVEL REACTIVE PRIMER WILL COVALENTLY BOND THE CERAMIC COATING TO THE WOOD AND RESIN SUBSTRATES. SOL-GEL PROCESSING STUDIES WILL ADDRESS TAILORABILITY OF THE ALUMINA-SILICATE COMPOSITION AND MICROSTRUCTURE. PULL-OFF TESTS WILL ASSESS COATING ADHERENCE ACHIEVED BY THE REACTIVE PRIMER. DNA'S DUST EROSION FACILITY WILL BE USED TO DETERMINE SOLID IMPACT EROSION RESISTANCE AS A FUNCTION OF CERAMIC COATING CHARACTERISTICS. TPL WILL BE ASSISTED BY THE CENTER FOR MICRO-ENGINEERED CERAMICS IN COATING DEVELOPMENT AND PDA ENGINEERING IN EROSION TESTING. COMBINED, THE PROGRAM TEAM HAS COMPLETE CAPABILITIES TO ACHIEVE AN ENGINEERING SOLUTION.