Patent ID: 6416564
Filing Date: 2002-07-09
Classification: C22B,C22C,C22F

Abstract:
A method of producing a nickel base superalloy that is substantially free of positive and negative segregation, the method comprising:casting an alloy that is a nickel base superalloy within a casting mold; annealing and averaging the alloy by heating the alloy at at least 1200Â° F. (649Â° C.) for at least 10 hours; electroslag remelting the alloy at a melt rate of at least 8 lbs/min. (3.63 kg/min.); transferring the alloy to a heating furnace within 4 hours of complete solidification; holding the alloy within the heating furnace at a first temperature of 600Â° F. (316Â° C.) to 1800Â° F. (982Â° C.) for at least 10 hours; increasing the furnace temperature from the first temperature to a second temperature of at least 2125Â° F. (1163Â° C.) in a manner to inhibit thermal stresses within the alloy; holding at the second temperature for at least 10 hours; vacuum arc remelting a VAR electrode of the alloy at a melt rate of 8 to 11 lbs/minute (3.63 to 5 kg/minute) to provide a VAR ingot.