Alloy composition

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.

1 . An alloy consisting essentially of, by weight percent, between 18 and 20% chromium, between 8.5% and 12% cobalt, between 6.4 and 9.4% iron, up to 1.5% manganese, between 3.5 and 5.3% tungsten, up to 1.5% niobium, between 0.4% and 1% tantalum, up to 1.5% silicon, between 1.5 and 2.3% aluminium, between 0.5 and 2.4% titanium, between 0.005 and 0.04% carbon, between 0.005 and 0.07% boron, and between 0.02 and 0.10% zirconium, the balance being nickel save for incidental impurities. 
     
     
         2 . An alloy according to  claim 1 , wherein the alloy consists essentially of, by weight percent, between 18 and 20% chromium, between 8.5% and 12% cobalt, between 6.4 and 9.4% iron, up to 1.5% manganese, between 3.5 and 5.3% tungsten, up to 1.5% niobium, between 0.4% and 1% tantalum, between 0.1% and 1.5% silicon, between 1.5 and 2.3% aluminium, between 1 and 2.4% titanium, between 0.005 and 0.04% carbon, between 0.005 and 0.07% boron, and between 0.02 and 0.10% zirconium, the balance being nickel save for incidental impurities. 
     
     
         3 . An alloy according to  claim 1 , wherein the alloy comprises between 0.1% and 1.5% by weight silicon. 
     
     
         4 . An alloy composition according to  claim 1 , wherein the alloy consists essentially of, by weight percent, between 20 and 20.4% chromium, between 9.3% and 11.3% cobalt, between 7.4 and 8.4% iron, between 0.2 and 0.4% manganese, between 4.2 and 4.6% tungsten, between 1 and 1.2% niobium, between 0.6% and 0.8% tantalum, between 0.2 and 0.4% silicon, between 1.8 and 2.0% aluminium, between 1.6 and 1.8% titanium, between 0.015 and 0.025% carbon, between 0.015 and 0.025% boron, and between 0.05 and 0.07% zirconium, the balance being nickel save for incidental impurities. 
     
     
         5 . An alloy composition according to  claim 4 , wherein the alloy consists essentially of by weight percent, 20.2% chromium, 10.3% cobalt, 7.9% iron, 0.3% manganese, 4.4% tungsten, 1.1% niobium, 0.7% tantalum, 0.3% silicon, 1.9% aluminium, 1.7% titanium, between 0.015 and 0.025% carbon, between 0.015 and 0.025% boron, and between 0.05 and 0.07% zirconium, the balance being nickel save for incidental impurities. 
     
     
         6 . An alloy according to  claim 1 , wherein the incidental impurities include oxygen. 
     
     
         7 . An alloy according to  claim 1 , wherein the ratio by weight of titanium to aluminium is less than 0.5. 
     
     
         8 . An alloy according to  claim 1 , wherein the ratio by weight of chromium to titanium is greater than 10. 
     
     
         9 . A gas turbine engine component formed of an alloy in accordance with  claim 1 . 
     
     
         10 . A gas turbine engine component according to  claim 8 , wherein the component comprises a combustor liner. 
     
     
         11 . A gas turbine engine comprising a component according to  claim 8 .