Page 57 - Curriculum Visions Dynamic Book

(Below) Like many pieces of sports equipment, tennis racket heads need to be lightweight. But they also need to stand up to the forces of the nylon strings and the tantrums of the users. Golf club shafts similarly have to withstand huge forces
and need to provide a controlled springiness. Carbon-fibre-reinforced resin can be moulded into elegant shapes and so suit the sophisticated design demands and fashions expected in modern sporting goods.
(Right) Ski poles, also used for walking, need to be lightweight and strong enough to bear the weight of the user.
to char. Provided the charring is done under conditions of very little oxygen, the charred residue is almost pure carbon. (You can compare this process with the way that charcoal is produced by burning wood in a kiln where the air is excluded.)
Charred fibres are exceptionally fragile, and so the fibre is often made up into a fabric before charring. The carbonized fabric then consists of interlaced carbon fibres in mat form.
The fibres used for making the original matting include rayon, whose carbonized matting is widely used as a thermal shield in space vehicles such as the nose and underbelly shield of the Space Shuttle (where the material is protected by thin ceramic tiles).
When acrylics are used, the intention is to produce a higher-strength fibre than that produced from rayon. As the acrylic mat is carbonized, the fibres are put under tension. This makes the carbon atoms more aligned in a single direction. This kind of carbon fibre is used as a reinforcer for plastic composite materials such as those for making
airplanes.
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