Large diameter ingots of nickel base alloys

An ingot of a nickel base alloy comprising:

• about 50.0 to about 55.0 weight percent nickel;
• about 17 to about 21.0 weight percent chromium;
• 0 up to about 0.08 weight percent carbon;
• 0 up to about 0.35 weight percent manganese;
• 0 up to about 0.35 weight percent silicon;
• about 2.8 up to about 3.3 weight percent molybdenum;
• at least one of niobium and tantalum wherein the sum of niobium and tantalum is about 4.75 up to about 5.5 weight percent;
• about 0.65 up to about 1.15 weight percent titanium;
• about 0.20 up to about 0.8 weight percent aluminum;
• 0 up to about 0.006 weight percent boron;
• and
• iron and incidental impurities;
• wherein the ingot has a diameter greater than 30 inches and is substantially free of negative segregation and is free of freckles and substantially free of other positive segregation.

A VAR ingot of a nickel base alloy produced by the 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 overaging the alloy by heating the alloy at at least 1200° F. for at least 10 hours;
• electroslag remelting the alloy at a melt rate of at least 8 lbs/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 600° F. to 1800° F. for at least 10 hours;
• increasing the furnace temperature from the first temperature to a second temperature of at least 2125° F. in a manner to inhibit thermal stresses within the alloy;
• holding at the second temperature for at least 10 hours;
• and
• vacuum arc remelting a VAR electrode of the alloy at a melt rate of 8 to 11 lbs/minute to provide a VAR ingot.