Porsche rolling out carbon fiber wheels

Sports car specialist Porsche is bringing an all-carbon-fiber-reinforced plastic wheel to the market, saying it will be the first global automaker to offer the CFRP wheel when it debuts in early 2018 as an option on the 911 Turbo S Exclusive series.

At 8.8 kilograms, the composite wheel is 20 percent lighter than an equivalent aluminum alloy wheel, but Porsche — a unit of Germany's Volkswagen AG — says the wheels are also 20 percent stronger. That strength combined with lighter weight will improve performance with "more spontaneity in both acceleration and braking," Porsche said in an Aug. 18 news release.

The wheels will be priced at more than 15,000 euros ($17,600) for a complete set.

The wheel's center is produced using woven carbon fiber fabric, with the fabric cut and assembled over 200 individual components.

To make the rim, Porsche has turned to a braided carbon fiber, investing in what it claims is the world's largest carbon fiber braiding machine, with a 9-meter diameter, made by Herzog GmbH of  Oldenburg, Germany.

The carbon fiber fabric center is then braided into the rim.

All together, the wheels use 18 kilometers of carbon fiber material.

The braiding machinery is also used to integrate the rim and center parts with each other, prior to resin impregnation and initial resin curing in a press at high pressure and temperature. Following post-molding final cure, then cooling, the central lock is inserted and clear protective lacquer is applied to the entire wheel to aesthetically emphasize its full-carbon construction.

Porsche says the low-waste braided CF process results in particularly high density and compactness that benefits wheel rigidity.