Precipitation hardened cobalt-nickel based superalloys and articles made therefrom

摘要

A precipitation hardenable cobalt-nickel based superalloy is disclosed. The alloy is characterized by the following weight percent compositions. C about 0.01 to about 0.15, Cr about 6.00 to about 15.00, Ni about 30.00 to about 45.00, W about 3.00 to about 15.00, Ti about 0.50 to about 4.00, Al about 3.00 to about 7.00, Nb maximum about 2.50, Ta up to about 6.00, Hf maximum about 1.50, Zr maximum about 1.50, B maximum about 0.20, Mo maximum about 2.50, Si maximum about 1.50, The balance of the alloy is cobalt and common impurities. The alloy offers a new combination of strength and ductility after prolonged exposure to the high operating temperatures found in gas turbines and jet engines. Fine grain steel articles made from the present alloys are also disclosed. Steel articles are characterized by a continuous surface layer of Al