Process for applying coatings of zirconium and/or titantuim and a less noble metal to metal substrates and for converting the zirconium and/or titanium to an oxide, nitride, carbide, boride or silicide
US4935073A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 1987 |
| Grant date | Jun 19, 1990 |
| Priority date | — |
| Expiry date | Oct 21, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C26/00
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Protective coatings are applied to substrate metals by coating the metal surface, e.g. by dipping the substrate metal in a molten alloy of the coating metals, and then exposing the coating at an elevated temperature to an atmosphere containing a reactive gaseous species which forms an oxide, a nitride, a carbide, a boride or a silicide. The coating material is a mixture of the metals M.sub.1 and M.sub.2, M.sub.1 being zirconium and/or titanium, which forms a stable oxide, nitride, carbide, boride or silicide under the prevailing conditions. The metal M.sub.2 does not form a stable oxide, nitride, carbide, boride or silicide. M.sub.2 serves to bond the oxide, etc. of M.sub.1 to the substrate metal. Mixtures of M.sub.1 and/or M.sub.2 metals may be employed. This method is much easier to carry out than prior methods and forms superior coatings. Eutectic alloys of M.sub.1 and M.sub.2 which melt substantially lower than the melting point of the substrate metal are preferred.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.