Large Area Thin Film Corrosion Resistance via CCVD

Corrosion damage to aluminum structural components is very costly to both the government and commercial industry; viable treatments and/or protective procedures are required to limit it. Paint and related conventional coatings are commonly used to combat corrosion, although such coatings often may degrade quickly requiring frequent reapplication or touch-up; this is expensive and labor-intensive, especially in the field. Higher performance conversion coatings are prepared with processes which use hexavalent chromium, now considered to be a major health and environmental hazard. Thus, there is a compelling need for alternative, environmentally benign, low-cost coating technologies to protect aluminum components and structures subjected to corrosive environments. In addition, reduced weight is desired. MicroCoating Technologies, Inc. proposes to develop its safe, clean, economical Combustion Chemical Vapor Deposition (CCVD) process to fabricate high-quality, dense, pinhole-free, metal-oxide thin films as replacements for the chromate conversion coatings. The patented CCVD method is an open atmosphere deposition system capable of true heterogenous vapor deposition of dense, high quality films but at a fraction of the cost of the traditional vacuum processes, Chemical Vapor Deposition and Physical Vapor Deposition (PVD). Since CCVD processing is not confined to a reaction chamber or furnace, coating of large objects such as aircraft structural components is viable. We have already completed experimental work on low temperature deposition of CCVD coatings on aluminum and copper substrates. Our trial coatings display excellent performance as corrosion-barriers under wet conditions in tests performed by both Battelle (1300+ hours of saltwater spray) and an industrial partner (30 day SWAAT). We will detail these preliminary results further in the proposal. In Phase I, we will build on this initial success and work with our industrial collaborators to develop CCVD metal-oxide coatings with negligible weight for protection of aluminum structural components in both military and commercial applications. Phase I success will lead to a Phase II program to scale and automate the CCVD process for high rate, low cost production. This SBIR research will be planned, developed and commercialized through Phase III in collaboration with our industrial partners.