Reinforced carbon–carbon

Carbon fibre-reinforced carbon (a.k.a. Carbon–Carbon, abbreviated C/C or Reinforced Carbon-Carbon, abbreviated RCC or Carbon-Fiber-Reinforced Carbon, abbreviated CFRC) is a composite material consisting of carbon fiber reinforcement in a matrix of graphite. It was developed for the nose cones of intercontinental ballistic missiles, and is most widely known as the material for the nose cone and wing leading edges of the Space Shuttle orbiter. It has been used in the brake systems of Formula One racing cars since 1976; carbon–carbon brake discs and pads are a standard component of Formula One brake systems.

Carbon–carbon is well-suited to structural applications at high temperatures, or where thermal shock resistance and/or a low coefficient of thermal expansion is needed. While it is less brittle than many other ceramics, it lacks impact resistance; Space Shuttle Columbia was destroyed during atmospheric re-entry after one of its RCC panels was broken by the impact of a piece of foam insulation from the Space Shuttle External Tank. This catastrophic failure was due in part to original shuttle design requirements which did not consider the likelihood of such violent impacts.

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.

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