Heat treatment of martensitic stainless steel after remelting under a layer of slag
US8808474B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 11, 2010 |
| Grant date | Aug 19, 2014 |
| Priority date | — |
| Expiry date | Mar 2, 2031 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2211/009
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method fabricating a stainless martensitic steel, including electroslag remelting then cooling an ingot of the steel, then at least one austenitic thermal cycle heating the ingot above its austenitic temperature followed by a cooling. During each cooling: if the cooling is not followed by an austenitic thermal cycle, holding the ingot at a holding temperature included in the ferritic-pearlitic transformation nose for a hold time longer than sufficient for transforming the austenite into a ferritic-pearlitic structure in the ingot as completely as possible at the holding temperature; if the cooling is followed by an austenitic thermal cycle, before its minimum temperature falls below the martensitic transformation start temperature, the ingot is either held throughout the period between the two austenitic thermal cycles at a temperature above the austenitic transformation completion temperature on heating, or held at the holding temperature included in the ferritic-pearlitic transformation nose.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.