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A method is provided for fabricating silicon carbide articles which comprises hot pressing a homogeneous mixture of carbonaceous particles and silicon carbide powder. The presence of the carbon limits grain growth so that a silicon carbide product having greatly improved physical properties is obtai

A method is provided for fabricating silicon carbide articles which comprises hot pressing a homogeneous mixture of carbonaceous particles and silicon carbide powder. The presence of the carbon limits grain growth so that a silicon carbide product having greatly improved physical properties is obtained. The method is suitable for fabricating structural elements, e.g., structural components in the hot sections of air breathing propulsion systems.

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A method of fabricating an article of silicon carbide which comprises the following steps: a. blending a0.75 to 20 weight percent of finely divided carbon particles, based upon the weight of the silicon carbide, so as to form a homogeneous mixture consisting essentially of the afOrementioned ingredi

A method of fabricating an article of silicon carbide which comprises the following steps: a. blending a0.75 to 20 weight percent of finely divided carbon particles, based upon the weight of the silicon carbide, so as to form a homogeneous mixture consisting essentially of the afOrementioned ingredients; b. milling the homogeneous mixture of step (a) in a liquid mixing medium which is inert to the ingredients of the mixture until the ingredients are completely dispersed; c. drying the mixture of step (b) so as to evaporate the mixing medium; d. initially compressing the dried mixture of step (c) in a compression zone formed of graphite and lined with a sheet of graphite at a temperature in the range of about 700°to 1200°C and at a pressure ranging from about 400 to 600 psi, the compressing being carried out under a vacuum of about 105 to 103 torr or under a blanket of an inert gas for a period of about 15 minutes to 1 hour; e. compressing the resulting compacted article in the compression zone at a temperature in the range of about 1950°to 2250°C and at a pressure ranging from about 4000 to 6000 psi for a period of about 10 to 20 minutes, the compressing being carried out under a vacuum of about 105 to 103 torr or under a blanket of an inert gas for a period of about 10 to 20 minutes; f. allowing the compression zone to cool to room temperature over a period of about 1 to 4 hours; and g. recovering the silicon carbide article from the compression zone.