German automaker Porsche has become the world’s first vehicle manufacturer to offer lightweight wheels with braided carbon fiber. They are available now as an option for the Porsche 911 Turbo S Exclusive Series. Carbon, the characteristically black high-tech material, can be fully appreciated in the new wheels with a protective layer of clear lacquer.
|The world’s largest carbon fiber braiding machine (below), with a diameter of approximately nine meters, is used to fabricate the CFRP wheels (above), which weigh 20% less than alloy wheels.|
Together, the wheels weigh around 8.5 kilograms less than standard alloy wheels, representing a reduction of 20 per cent. They are also 20 per cent stronger. With a reduced unsprung weight, the tires trail the surface of the road better and are perfectly optimized for absorbing longitudinal and lateral forces. Lower rotating masses mean more spontaneity both in acceleration and braking. The result is increased driving dynamics and driving pleasure.
Manufactured entirely from carbon fiber reinforced plastic (CFRP), the wheel is essentially comprised of two components. The wheel centre is made from carbon-fiber fabric. This involves cutting and assembling over 200 individual components. The second component is the rim base made from braided carbon fiber by what is currently the world’s largest carbon fiber braiding machine with a diameter of approximately nine meters.
The wheel centre is then braided into the rim base. The assembled wheel is impregnated with thermoset resin and cured at high pressure and high temperatures. The finished wheel is hardened at high temperatures followed by a long cooling process. The central lock is then inserted into the finished wheel and the wheel is protected with a clear lacquer coat.
Porsche is the first company in the global automotive industry to use this extremely complex technology. The braiding technology offers key advantages over the more conventional method of manufacturing pre-impregnated carbon fiber fabric (the prepreg method): The Porsche production technique makes the material structure of the carbon considerably denser and more compact. This increases rigidity. Using the material more efficiently also produces less waste. The new carbon wheel is made from a total of 18 kilometers of carbon fiber or eight square meters of carbon-fiber fabric.
From the beginning of 2018, the new carbon wheels will be available as an option for the 911 Turbo S Exclusive Series. In Germany, a set of wheels will be priced at EUR15,232 ($17,910) including value added tax.