PROPERTIES OF DIAMOND COMPOSITE FILMS GROWN ON IRON SURFACES

We report for the first time that diamond composite films consisting of diamond particles, hydrogenated amorphous carbon, and/or fluorocarbon films can be successfully deposited on carbon steel and 304 stainless-steel substrates by plasma-assisted chemical vapor deposition. The use of thin (approximately 200-angstrom) silicon buffer layer proves to be effective in inhibiting surface catalytic effect of iron and also prevents carbon species from diffusing into the bulk. The composite films adhere well to the substrates even upon imposing a scratch load of 68 newtons. They can also be bent up to 10-degrees and still remain chemically inert and impermeable to salt solution. One of the potential applications of these films is for protective coating on sheet metal surfaces.