Patent ID: 11898228
Assignee: ROLLS-ROYCE PLC
Field: Materials, metallurgy (Chemistry)
Classification: CPC C | IPC C

Claim 20:
21. A nickel-cobalt based superalloy composition consisting of, by weight:
33.5 to 54 percent nickel;
19.5 to 36 percent cobalt;
9.0 to 12.0 percent chromium;
3.9 to 5.5 percent aluminium;
4.5 to 9.5 percent tungsten;
up to 5.5 percent iron;
2 to 3.5 percent molybdenum;
0.6 to 3.80 percent tantalum;
0.15 to 2.2 percent titanium;
up to 1.75 percent niobium;
up to 0.1 percent hafnium;
0.005 to 0.03 percent carbon;
0.001 to 0.02 percent boron;
0.005 to 0.06 percent zirconium;
up to 0.3 percent silicon;
up to 0.6 percent manganese; and
the balance being impurities,
wherein the nickel-cobalt based superalloy has a bimodal size distribution of γ′ precipitates that includes:
secondary γ′ precipitates that are between 50 and 200 nm in size, and
tertiary γ′ precipitates that are less than 35 nm in size.