Magna International Inc. has delivered a carbon fiber subframe prototype to Ford it says will reduce weight and tooling costs, and hopes to rule on mass production by year end.
The new component, being tested in a Ford Fusion sedan, weighs 34 percent less than a traditional metal subframe and replaces 45 steel parts with two molded and four metallic ones.
The subframe undergirds the front quarter of the vehicle, providing a place to attach the engine and wheels. Magna's prototype, developed with Ford, explores new ground in using lightweight but pricey carbon fiber in structural parts of a vehicle.
"We delivered a series of parts to the customer at the end of last year, and they've already started component testing," said Andrew Swikoski, Magna's global product line director for lightweight composites. "By the end of the year, we'll know whether the technology is ready for production or not."
Carbon fiber is lightweight and strong, making it a good substitute for steel as engineers race to shave weight from cars to boost fuel economy. But carbon fiber is also costly.
Swikoski said Magna's subframe not only reduces weight by more than a third, but it also cuts tooling investment by 30 to 40 percent by reducing the number of subcomponents needed.
Magna's carbon fiber composite blends multiple materials to stay affordable, Swikoski said.
Validation will include crash resistance. But carbon fiber, while strong, is also brittle and does not absorb impacts as well as more ductile metal. The carbon fiber subframe absorbs about 5 percent of crash energy and resorts to dropping the engine below the vehicle in a collision.
"It's not meant to be a primary crash absorber," Swikoski said, adding that carbon fiber will still need to be used along with high-strength steel and other metals to buffer impacts.
Looking to the future, Swikoski said it would be a "logical next step" to begin developing carbon fiber materials for side doors. Carbon fiber rear liftgates are already in production, but assuring safety with carbon fiber side doors is more difficult, he said.