Molds are fabricated having a substrate of high density, high strength ultrafine grained isotropic graphite, and having a mold cavity coated with pyrolytic graphite. The molds may be made by making the substrate (main body) of high density, high strength ultrafine grained isotropic graphite, by, for example, isostatic or vibrational molding, machining the substrate to form the mold cavity, and coating the mold cavity with pyrolytic graphite via a chemical deposition process. The molds may be used to make various metallic alloys such as nickel, cobalt and iron based superalloys, stainless steel alloys, titanium alloys and titanium aluminide alloys into engineering components by melting the alloys in a vacuum or under a low partial pressure of inert gas and subsequently casting the melt in the graphite molds under vacuum or low partial pressure of inert gas.

Title
Castings of metallic alloys with improved surface quality, structural integrity and mechanical properties fabricated in anisotropic pyrolytic graphite molds under vacuum
Application Number
10/151871
Publication Number
20030042001
Application Date
May 22, 2002
Publication Date
March 6, 2003
Inventor
Donald W Scott
Peoria
AZ, US
Ranjan Ray
Phoenix
AZ, US
Agent
Stevens Davis Miller & Mosher
DC, US
IPC
B22C 03/00
B22C 01/00
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