Method for forming material surfaces
US4326898A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 20, 1980 |
| Grant date | Apr 27, 1982 |
| Priority date | — |
| Expiry date | Feb 20, 2000 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C8/26
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Material surfaces are provided which maintain their characteristic properties over long periods and which resist degradation by the environment in which they are utilized. The surfaces are formed by exposing a surface of atomically clean material to a gas or liquid which interacts with the clean surface to form a composition having the properties desired and which is stable against degradation in the environment of use. The process is useful, for example, to render metals or metal alloys, such as iron or iron alloys, stable against oxidation by air by exposing the atomically clean surface to an ultrapure nitrogen environment, prior to exposure to a degrading environment, such as air. A new oxidation-resistant iron surface composition also is provided which comprises body-centered iron structures including nitrogen atoms interstitially. This surface composition is essentially free of face-centered cubic iron-nitrogen structures and martensite iron-nitrogen structures as well as morphologies derived from the thermal decomposition of those structures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.