Process for applying coatings of zirconium and/or titanium and a less noble metal to metal substrates and for converting the zirconium and/or titanium to a nitride, carbide, boride, or silicide
US4857116A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 1987 |
| Grant date | Aug 15, 1989 |
| Priority date | — |
| Expiry date | Oct 21, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C28/00
- 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 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 nitride, carbide, boride or silicide under the prevailing conditions. The metal M.sub.2 does not form a stable nitride, carbide, boride or silicide. M.sub.2 serves to bond the carbide, 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.