Non-Chromate CCVD Coating for Naval Engine Components

Chrome replacement and corrosion protection coatings in thermal environments is needed. Combustion chemical vapor deposition (CCVDsm), a process invented by the principal investigator, is the only open atmosphere CVD technique for ceramics and metals. The CCVD method has been shown to inexpensively and quickly apply dense, adherent thin films in a continuous manner. This technology can be used for the production of corrosion resistant coatings on the outside and inside of assembled engine and exhaust components. CCVD processed alumina coatings alumina coatings has previously demonstrated a 90% reduction in high temperature corrosion of a metal substrate. The CCVD method is a low cost, high quality and versatile process. It does not require a reaction chamber or furnace, yet the thin films produced are comparable in quality to CVD films, and allow depositions over a large surface area as is required for engine components. The deposition apparatus is light weight and no water cooling is needed. The thin film multilayering capability of CCVD processing, which is not line-of-sight limited, is needed to bring desired thin film coatings with corrosion resistant properties to in situ applications. We have produced CVD quality films of numerous materials including silica and alumina using CCVD in the open atmosphere onto numerous steels. These coatings can save the cost of more expensive corrosion resistant alloys and provide superior performance. In this project, thin films of oxidation and corrosion control coating will be grown onto flat and irregular substrates in the open atmosphere using CCVD. The composition, morphology, microstructure, wear and high temperature corrosion properties of the coated substrates will be determined as a function of deposition conditions. A series of run studies will be performed to optimize the deposition process. This research will demonstrate the ability of the CCVD technique to inexpensively deposit protective alumina, mullite, or other delineated materias onto engine components to obtain desired thermal and corrosion resistant properties.