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Reinforced Carbon-Carbon (RCC) consists of carbon fiber reinforcement in a matrix of graphite, often with a silicon carbide coating to prevent oxidation. It was developed for the nose cones of intercontinental ballistic missiles, and is used structurally in high-temperature applications, and where thermal shock or other coefficient of thermal expansion issues might arise, such as the nose cone and leading edges of the space shuttle.
Production
The material is made in three stages. First, material is laid up in its intended final shape, with carbon filament and/or cloth surrounded by an organic binder such as plastic or pitch. Often, coke or some other fine carbon aggregate is added to the binder mixture. Second, the lay-up is heated, so that pyrolysis transforms the binder to relatively pure carbon. The binder loses volume in the process, so that voids form; the addition of aggregate reduces this problem, but does not eliminate it. The voids are gradually filled by forcing a carbon-forming gas such as acetylene through the material at a high temperature, over the course of several days. This long heat-treatment process also allows the carbon to form into graphite crystals, and is the major reason for the material's high cost.
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