BMW AG could begin production of a car with a carbon-fiber body within five years.
Automakers are interested in using strong, lightweight carbon-fiber reinforced composites, but so far they've been cautious because of the high cost.
If BMW follows through on its Z22 concept vehicle, carbon-fiber suppliers could see the breakthrough they've been seeking in the auto market.
'This is going to be quite viable in some years,' said BMW spokesman Dave Buchko. 'There is no firm plan yet to put it into production, but it is entirely feasible.'
BMW introduced its concept Z22 in Germany in August.
Many automakers are looking at the potential of carbon fiber, but BMW has a lead on potential production, said Phillip K. Johnson, marketing manager for fiber supplier Zoltek Cos. Inc.'s automotive division.
'BMW is further along than any other auto company,' he said. 'They want to be a differentiator. They want to be a leader.'
BMW has experience with plastic body panels, said Buchko. Its Z1 - the first vehicle designed by BMW's Technik GmbH design and engineering unit - had a plastic outer shell.
BMW said the Z22 tests a series of advanced auto concepts, ranging from the body structure to electronic steering and braking. BMW focused on using manufacturing techniques that will allow it to make lightweight carbon-fiber-reinforced car bodies under production conditions by 2005.
BMW's Innovation and Technology Center in Landshut, Germany, is the center of the company's lightweight construction strategy. The unit was assigned to create a car that could perform as well as existing BMW vehicles, maintain the company's standards in the interior, and provide decent fuel efficiency.
Carbon-fiber body panels on an aluminum frame gave the weight savings needed to meet fuel efficiency targets while still maintaining structural strength.
The Z22 weighs 1,090kg, or 33 percent less than the 528i, on which it is based, the company said. Molding panels from reinforced plastic also allow it to reduce the number of body parts to 20 components from more than 80, while also cutting manufacturing time.
Carbon fiber still is about eight times more expensive than traditional steel. But if carmakers can spend less time making the vehicle, they can save personnel costs.
BMW sells more than 100,000 of its 5 series vehicles annually, said Buchko. That volume should translate into production savings.
Carbon fiber does offer some advantages over traditional car bodies, said David Cramer, vice president of technology partnerships for Hypercar Inc., an engineering company based in Basalt, Colorado, USA that reviews ways to bring new concepts into the auto industry, including lightweight materials.
In 1995, Cramer published a study comparing the cost of mass producing a car in carbon fiber or traditional steel, basing it on General Motors' Ultralite concept car.
While GM had spent $13,000 for a composite body on its one concept car, in mass production of at least 100,000 vehicles the company could turn out a carbon-fiber body for about $2,500. That compared with a steel body costing $1,750, he said.
Some of the savings come from carbon fiber's lighter weight. The plastic also allows engineers to change the design of the car and reduce the number of parts and the amount of time needed to build each vehicle, Cramer said.
He said that if the price of carbon fiber drops, the cost difference between the two bodies disappears. Zoltek has vowed to lower the price of its carbon fiber by early in 2001.
US carbon-fiber suppliers such as St. Louis-based Zoltek and Hexcel of Stamford, Connecticut, are pushing for acceptance of carbon fiber in mass market automobiles, which offers potential sales far greater than traditional low-volume aerospace applications.
Carbon fibers are already used extensively in auto racing and by top-end automakers including Lotus Cars Ltd. and Aston Martin Lagonda Ltd.
'All of our energies are focused on automotive,' said Zoltek's Johnson. 'The goal is not just to do a low-volume vehicle, but a mass market vehicle.'
A BMW, selling at $40,000 to $50,000 or more, has more room to absorb the higher price for carbon fiber than a typical North American mass-produced vehicle, Buchko said. In addition, European buyers traditionally are more willing to pay extra to have advanced technology in their cars.
Johnson said that automakers and their suppliers must learn how best they could use the material and how to mold it to their purposes. Likewise, carbon-fiber suppliers must research exactly what the auto industry needs and how they can meet that need.
And carmakers are more interested in chasing price than the aerospace industry ever was, he added.
'The devil is in the details,' agreed Hypercar's David Cramer. 'There are all sorts of little issues out there none of which is a real show stopper that will keep this from happening.'
Interest in carbon fiber is continuing to grow, Johnson said. High fuel prices and car buyers' demands to save gasoline will only force the issue further.
'The industry is positioned at a very opportune time where gas efficiency and lightweight materials are going to get attention,' he said. 'Everyone is intrigued.'