Iron-based alloy and nitridation treatment for PEM fuel cell bipolar plates
US7829194B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 2006 |
| Grant date | Nov 9, 2010 |
| Priority date | — |
| Expiry date | Dec 13, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31678
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A corrosion resistant electrically conductive component that can be used as a bipolar plate in a PEM fuel cell application is composed of an alloy substrate which has 10-30 wt. % Cr, 0.5 to 7 wt. % V, and base metal being Fe, and a continuous surface layer of chromium nitride and vanadium nitride essentially free of base metal. A oxide layer of chromium vanadium oxide can be disposed between the alloy substrate and the continuous surface nitride layer. A method to prepare the corrosion resistant electrically conductive component involves a two-step nitridization sequence by exposing the alloy to a oxygen containing gas at an elevated temperature, and subsequently exposing the alloy to an oxygen free nitrogen containing gas at an elevated temperature to yield a component where a continuous chromium nitride layer free of iron has formed at the surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.