CENTRIFUGAL CASTING OF NICKEL BASE SUPERALLOYS IN ISOTROPIC GRAPHITE MOLDS UNDER VACUUM

摘要

Methods for making various nickel based superalloys into engineering components such as rings, tubes and pipes (70) by melting of the alloys (60) in a vacuum chamber (50) or under a low partial pressure of innert gas and subsequent centrifugal casting of the melt in the graphite molds (80) rotating along its own axis under vacuum or low partial pressure of inert gas are provided. The molds have been fabricated by machining high density, high strength ultrafine grained isotropic graphite, wherein the graphite has been made by isostatic pressing or vibrational molding.