The use of a nickel chromium - - - cobalt alloy for in the case of high temperatures is resistant to casting parts

摘要

A creep-resistant alloy particularly for gas turbine parts, dies and valves has the following percentage composition, by weight: .Cr.6-12. .Co.5-30. .Mo.1-8. .V.0.2-2. .Al.4-9.8-12 in total .Ti.0.5-6.5.8-12 in total .B.0.001-0.1. .Zr.0.01-0.25. .C.0.01-0.5. .Ni and impurities.the balance.. The alloy may also contain Ta up to 4 and Nb up to 5. It may be used as cast or may be solution treated by heating to 1150-1205 DEG C. for 1/2 -4 hours in an inert atmosphere followed by rapid cooling in an inert atmosphere to below 925 DEG C. The alloy is then aged in service or by heating to 760-925 DEG C. to 1-20 hours. For use at temperatures above 950 DEG C. articles made from the alloy are preferably provided with an oxidation-resistant coating, e.g. Cr or oxidized Al.