Surface treatment of magnesium alloy castings for corrosion protection
US8608869B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 2010 |
| Grant date | Dec 17, 2013 |
| Priority date | — |
| Expiry date | Dec 14, 2031 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25D11/36
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method is disclosed for improving the corrosion behavior of cast magnesium alloy articles in which the magnesium alloy comprises an average composition of more than about 5 per cent by weight of aluminum. A microstructure with regions of varying aluminum content is developed during solidification. The microstructure comprises magnesium-rich grains generally surrounded by an aluminum-enriched phase on the boundaries between adjacent grains. The magnesium-rich grain interiors are then selectively chemically or electrochemically attacked to leave a more corrosion resistant aluminum-enriched surface on the articles. The corrosion resistance of the articles may be further enhanced by one or more of anodizing, aluminizing or painting the corrosion-resistant aluminum-enriched surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.