Abstract: A cobalt-nickel alloy composition comprising by weight (wt %): about 31 to 42 percent cobalt (Co); about 26 to 31 percent nickel (Ni); about 10 to 16 percent chromium (Cr); about 4 to 6 percent aluminum (Al); about 6 to 15 percent tungsten (W); the Co and Ni being present in an atomic ratio of about 1.3:1.

Abstract: A molybdenum based alloy composition including between 8.5% and 9.5% hafnium and 0.15% and 0.

Abstract: A cobalt-nickel alloy composition comprising by weight (wt %): about 31 to 42 percent cobalt (Co); about 26 to 31 percent nickel (Ni); about 10 to 16 percent chromium (Cr); about 4 to 6 percent aluminium (Al); about 6 to 15 percent tungsten (W); the Co and Ni being present in an atomic ratio of about 1.

Abstract: A molybdenum based alloy composition including between 15% and 20% niobium and 0.05% and 0.25% carbon.

Abstract: An alloy composition consisting essentially of, by atomic percent, between 6.5 and 8% of elements selected from the group consisting of aluminium, titanium, tantalum and niobium, between 37 and 47% of elements selected from the group consisting of chromium, cobalt, iron, molybdenum and tungsten, and between 1.8 and 3.8% of elements selected from the group consisting of tungsten, molybdenum, niobium and tantalum, and, optionally, by weight percent, up to 0.04% carbon, up to 0.07% boron, and up to 0.1% zirconium, the balance being nickel and incidental impurities.

Abstract: A cobalt-nickel alloy composition comprising by weight: about 29 to 37 percent cobalt; about 29 to 37 percent nickel; about 10 to 16 percent chromium; about 4 to 6 percent aluminium; at least one of Nb, Ti and Ta; at least one of W, Ta and Nb; the cobalt and nickel being present in a ratio between about 0.9 and 1.1.

Abstract: A nickel-base alloy having the following composition (in weight percent unless otherwise stated): Cr 10.5-15.0; Co 1.7-8.8; Fe 0-5.9; Si 0-0.65; Mn 0-0.65; Mo 0.3-2.3; W 2.3-4.4; Al 2.7-4.1; Nb 1.0-4.2; Ti 1.0-3.0; Ta 2.0-5.0; Hf 0.0-0.6; C 0.02-0.06; B 0.015-0.035; Zr 0.035-0.11; S<20 ppm; P<60 ppm; the balance being Ni and incidental impurities. The alloy has an improved combination of properties (principally resistance to surface environmental damage and dwell fatigue crack growth) compared with known alloys, and is intended to operate for prolonged periods of time above 700° C., and up to peak temperatures of 800° C.

Abstract: A molybdenum based alloy composition including between 15% and 20% niobium and 0.05% and 0.