Ni-base alloy, high-temperature member for steam turbine and welded rotor for turbine using the same, and method for manufacturing the same
US8883072B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 2009 |
| Grant date | Nov 11, 2014 |
| Priority date | — |
| Expiry date | Jun 15, 2031 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T50/60
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention provides, in a γ′ phase precipitation strengthening type Ni-base alloy, an alloy excellent in heat treatment capability and weldability and suitable for joint with a ferritic steel. Further, the present invention provides a welded turbine rotor having the strength, ductility, and toughness simultaneously over the whole welded structure when a precipitation strengthening type Ni-base alloy having a heatproof temperature of 675° C. or higher is joined to a ferritic steel.A Ni-base alloy according to the present invention contains cobalt, chromium, aluminum, carbon, boron, and at least either tungsten or molybdenum with the remainder being nickel and inevitable impurities, having an alloy composition including 12 to 25 percent by mass of Co, 10 to 18 percent by mass of Cr, 2.0 to 3.6 percent by mass of Al, 0.01 to 0.15 percent by mass of C, 0.001 to 0.03 percent by mass of B, the total amount of tungsten and molybdenum being 5.0 to 10 percent by mass.A welded turbine rotor is structured by joining or building up by welding a second Ni-base alloy to a first Ni-base alloy that a γ′ phase solid solution temperature thereof is 900° C. or higher and a creep fracture s…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.