Patent ID: 7799375
Filing Date: 2010-09-21
Classification: C04B

Abstract:
1. A method of producing a densified SiC article, the method comprising the steps of: a) supplying a porous preform formed entirely from a first phase of silicon carbide and having a known open porosity, wherein the porous silicon carbide preform is formed from a near-net shape graphite article; b) filling a substantial number of pores within the porous silicon carbide preform with a carbon precursor to produce a filled silicon carbide preform; c) heating the filled silicon carbide preform at a preselected carbonization temperature in a range from about 800° C. to about 1800° C. to produce a carbonaceous porous structure within the pores of the porous silicon carbide preform; d) comparing a carbonization weight of the carbonaceous porous structure to an initial weight of the porous silicon carbide preform to verify an expected weight gain of the carbonaceous porous structure based upon the known porosity of the porous silicon carbide preform; e) repeating steps (b) through (d) as necessary until the expected weight gain of the carbonaceous porous structure is provided within the pores of the porous silicon carbide preform; and f) contacting the carbonaceous porous structure with a silicon precursor at a temperature of 1650° C. so that the silicon precursor diffuses through the carbonaceous porous structure and reacts with carbon contained within the pores of the porous silicon carbide preform to produce a second phase of silicon carbide within the pores of the porous silicon carbide preform, such that the resulting densified silicon carbide article is densified with silicon carbide and exhibits lower porosity compared to the porous silicon carbide preform and is a SiC—SiC composite.