Steel for steam turbine blade with excellent strength and toughness
US9416436B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 24, 2013 |
| Grant date | Aug 16, 2016 |
| Priority date | — |
| Expiry date | Jun 7, 2033 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C38/44
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention aim at providing a steel for steam turbine blades which is excellent in terms of strength and toughness. The steel of the present invention has a composition which contains, in terms of % by mass, 0.02-0.10% of C, up to 0.25% of Si, 0.001-0.10% of Mn, up to 0.010% of P, up to 0.010% of S, 8.5-10.0% of Ni, 10.5-13.0% of Cr, 2.0-2.5% of Mo, 0.001-0.010% of N, 1.15-1.50% of Al, less than 0.10% of Cu, up to 0.20% of Ti, and the remainder being incidental impurities and Fe, and which satisfies 6.0≦Ni/Al≦8.0, 9.0≦Nieq≦11.0 and 17.0≦Creq≦19.0, in whichNieq=[Ni]+0.11[Mn]−0.0086([Mn]2)+0.44[Cu]+18.4[N]+24.5[C]Creq=[Cr]+1.21[Mo]+0.48[Si]+2.2[Ti]+2.48[A1].
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.