Ultratough high-strength weldable plate steel and method of manufacture thereof
US8016954B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 12, 2004 |
| Grant date | Sep 13, 2011 |
| Priority date | — |
| Expiry date | Oct 28, 2026 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2211/008
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A transformation toughened, high-strength steel alloy useful in plate steel applications achieves extreme fracture toughness (Cv & gt; 80 ft-lbs corresponding to KId & equals; 200 ksi.in½) at strength levels of 150-180 ksi yield strength, is weldable and formable. The alloy is characterized by dispersed austenite stabilization for transformation toughening to a weldable, bainitic plate steel and is strengthened by precipitation of M2C carbides in combination with copper and nickel. The desired microstructure is a matrix containing a bainite-martensite mix, BCC copper and M2C carbide particles for strengthening with a fine dispersion of optimum stability austenite for transformation toughening. The bainite-martensite mix is formed by air-cooling from solution treatment temperature and subsequent aging at secondary hardening temperatures to precipitate the toughening and strengthening dispersions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.