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Carbon fibre-reinforced carbon (aka Carbon–Carbon, abbreviated C/C or Reinforced Carbon-Carbon, abbreviated RCC or Carbon-Fiber-Reinforced Carbon, abbreviated ) 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. ==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. Third, 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 larger graphite crystals, and is the major reason for the material's high cost, exceeding $100,000 per panel. The grey "Reinforced Carbon–Carbon (RCC)" panels on the space shuttle's wing leading edges and nose cone cost NASA $100,000/sq ft to produce. Although much of this cost was a result of the advanced geometry and research costs associated with the panels. C/C is a generally hard material that can be made highly resistant to thermal expansion, temperature gradients, and thermal cycling, depending on how the fibre scaffold is laid up and the quality/density of the matrix filler. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Reinforced carbon–carbon」の詳細全文を読む スポンサード リンク
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