Steel for chimney or gas duct, excellent in pitting resistance and rust adhesion
US5820819A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Aug 20, 1996 |
| Grant date | Oct 13, 1998 |
| Priority date | — |
| Expiry date | Aug 20, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C38/50
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention has an object to provide a steel for a chimney or a gas duct, which is excellent in pitting resistance and rust adhesion in a corrosive environment caused by combustion waste gas in a plant in which the combustion of natural gas occurs. Pitting resistance and rust adhesion are remarkably improved in the steel of the present invention which steel is prepared by using a 5% Cr steel as the base, while reducing an impurity sulfur to not more than 0.010 wt. %, adding titanium within a range of 0.005 to 0.05 wt. %, and further adding nickel alone within a range of 1.0 to 2.5 wt. %, or adding molybdenum alone within a range of 0.10 to 1.0 wt. %, or adding in combination therewith trace amount of copper or molybdenum within a range of 0.10 to 1.0 wt. %.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.