Method of welding neutron irradiated metallic material
US5695666A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 1995 |
| Grant date | Dec 9, 1997 |
| Priority date | — |
| Expiry date | Jun 20, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D7/04
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
In a case of welding a highly neutron-irradiated austenitic stainless steel, the portion to be welded is heated under a condition of temperature and time in a predetermined range before welding. In this moment, chromium carbide (Cr.sub.23 C.sub.6) precipitates in the grain boundaries of the stainless steel. Welding is performed the state described above is obtained. Since, chromium carbide has been precipitated in the grain boundary by the heat treatment before welding, any helium atoms generated through nucleus conversion of Ni, are apt to be trapped with the chromium carbide, thereby reducing the number of gas bubbles formed by gathering the helium atoms in the grain boundaries. As a result, since decrease in the strength of the grain boundaries due to helium gas bubbles is moderated, it is possible to prevent occurrence of cracks during welding.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.