Murray, George T.
Department head—Metallurgical Engineering Dept., California Polytechnic State University, San Luis Obispo, CA
Pages: 14 Published: Jan 1988
In liquid or gaseous media, certain additives, called inhibitors, can occupy, via a strong binding energy to the base metal, atom sites on the metal surfaces, thus preventing a metal-hydrogen bond and thereby inhibiting the entry of hydrogen into the base metal. For both metallic and nonmetallic solid films, hydrogen entry can be prevented or reduced if the film has a lesser binding energy for hydrogen than the base metal and if a low solubility and/or a low diffusivity for hydrogen. Nonmetallic films appear to be the better films for preventing hydrogen entry and subsequent embrittlement of the base metal.
Data are presented for oxide and nitride films in the 50 to 3000-nm range of thickness. A 50-nm-thick film of sputtered alumina (A12O3) and a 3000-nm-thick, thermally grown oxide film appear to prevent hydrogen embrittlement in the precipitation-hardening stainless steels.
hydrogen embrittlement, precipitation hardened, stainless steels, surface films
Paper ID: STP45310S