Inhibited annealing of ferrous metals containing chromium
US4334938A · kind A · utility
4Cited by
9References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 22, 1980 |
| Grant date | Jun 15, 1982 |
| Priority date | — |
| Expiry date | Aug 22, 2000 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D6/002
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for limiting the absorption of nitrogen by ferrous metal containing chromium as an alloying additive (e.g. stainless steel) during high temperature annealing in an atmosphere of nitrogen and hydrogen by controlled additions of an inhibitor selected from the group consisting of water vapor, oxygen, nitrous oxide, carbon dioxide or mixtures thereof to the atmosphere while controlling the dew point of the furnace atmosphere and/or the ratio of the partial pressure of the inhibitor to the partial pressure of the hydrogen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.