Abstract: A method of heat treating articles cast of a superalloy, comprising a nickel-base alloy capable of forming a chromium carbide precipitate, such as INCONEL 939.TM.. The method includes selective heating of the article to cause chromium and carbon nuclei in the lattice of the crystals in the superalloy to go into solution, and selective cooling of the article to cause the formation of discrete chromium carbide nuclei along the grain boundary of the crystals. Additional heating steps may be performed to enhance the size of the chromium carbide nuclei. Articles so treated have improved mechanical properties.

Abstract: Heat treatments are described which improve subsequent HIP treatment results of superalloy articles. The heat treatments substantially eliminate certain low melting phases which otherwise would cause problems relating to gas entrapment during a HIP process. The articles are heated to a temperature near but below the intended HIP temperature for a period of time sufficient to reduce the low melting phase.