Method for finishing matted surface on a metal-made article for personal ornament
US4507184A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 1984 |
| Grant date | Mar 26, 1985 |
| Priority date | — |
| Expiry date | Oct 24, 2004 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25F3/16
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The invention provides a means for solving the difficult problem of the deposition of stain in the recesses to cause loss of beautiful appearance on the matted surface of an article for personal ornament made of titanium, zirconium or an alloy thereof formed by honing or barrel finishing. The method comprises the steps of (a) forming a first matted surface with microscopically fine protrusions and recesses on the article by honing or barrel finishing, (b) forming a hardened layer on the matted surface by nitriding, carbonizing, boriding or oxidizing, (c) partially removing the hardened layer covering the protrusions on the matted surface by a first electrolytic or chemical polishing, (d) forming a second matted surface on the article by honing or barrel finishing, and (e) partially removing the surface layer at the protrusions by a second electrolytic or chemical polishing to smoothen the surface leaving a sandy appearance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.