BMW AG is continuing its research into carbon fiber, with production under way in Europe for a car using a carbon-fiber-reinforced roof system.
The Munich, Germany-based carmaker produced a concept carbon-fiber car in 2000 as part of a technology experiment. Now it is making the roof of its M3 CSL from a proprietary process in Landshut, Germany, that it said improves overall production efficiency.
In developing both the materials and technologies, BMW has improved and automated production of carbon-fiber components, providing a ``foundation for the increased use of carbon fiber materials in a modern automobile,'' the automaker said in a July 16 report.
The manufacturing process begins by placing five layers of carbon fiber on top of each other for pre-forming, then uses resin transfer molding to produce the final roof system in an 1,800-ton press.
The entire production time is one-fifth that of traditional molding programs, the company said. The roof also is 13.2 pounds lighter than the standard component, or half the weight.
Carmakers must consider ways to reduce the environmental footprint of autos, said Norbert Reithofer, a BMW board member. The German company's lightweight technology effort considers a variety of potential weight-saving materials, including carbon fiber, aluminum and magnesium.
``Since there is no such thing as the `ideal' all-round lightweight material, the BMW Group ... is looking for intelligent combinations of metals and synthetic materials,'' he wrote.
The M3 CSL is sold only in Europe. It joins a small, but growing, number of production vehicles using carbon fiber, including DaimlerChrylser AG's Dodge Viper and some versions of General Motors Corp.'s Corvette.