Every bright spot comes with a dark side. Such is the case
with the auto industry's efforts to slim down vehicles to
improve fuel economy and meet ever-tightening emissions
standards. Automakers are racing to incorporate lightweight
materials to meet their goals, but some of the lightening
efforts come with serious sticker shock.
"The use of advanced materials such as magnesium, aluminum
and ultra high-strength boron steel offers automakers
structural strength at a reduced weight to help improve fuel
economy and meet safety and durability requirements," said
Robert Parker, director of product communications at Ford Motor
Co., Dearborn, Mich.
High-strength steels (HSS) played prominently in the efforts
of Japan's Mazda Motor Corp. to shave more than 220 pounds off
its much-anticipated 2010 Mazda2 subcompact compared with its
predecessor. And Tokyo-based Nissan Motor Co. Ltd. slimmed down
its new 370Z roadster by 95 pounds thanks to a wider
application of HSS, and for the first time aluminum door
panels, an aluminum hatch and an all-aluminum hood (the
previous aluminum hood design utilized steel
"We are working to reduce the thickness of steel sheet by
enhancing the strength, expanding the use of aluminum and other
lightweight materials, and reducing vehicle weight by
rationalizing vehicle body structure," a Nissan spokesman said.
The automaker has committed to reducing the weight of its
vehicle fleet by an average of 15 percent by 2015 from its 2005
Aluminum and advanced high-strength steels (AHSS) are
expected to figure prominently in General Motors Co.'s future.
The Detroit-based automaker's use of AHSS is expected to top
120,000 tonnes in 2010, up from less than 10,000 tonnes in
2004, according to the American Iron and Steel Institute.
Aluminum, meanwhile, will be making its way into the wheels,
blocks, hoods, tailgates and bumpers of GM vehicles at an
increasing rate, according to Mark Verbrugge, director of the
Chemical Sciences and Materials Systems Laboratory at GM's
Research and Development Center. "We use a lot of aluminum
today-about 300 pounds per vehicle-and are likely to use more
lightweight materials in the future," he said.
Composites also are making inroads into automotive design,
albeit it at a slower pace than AHSS and aluminum.
Magna International Inc., Canada's biggest auto industry
supplier, has announced plans to create a $7.2-million research
facility in collaboration with the Canadian government that
would develop auto parts technology using lightweight
The U.S. Energy Department's Oak Ridge National Laboratory
in Tennessee was recently allocated $34.7 million to establish
the Carbon Fiber Technology Center to identify and develop
low-cost carbon fiber automotive applications.
The challenge many of these alternative materials face,
however, is cost. A Porsche Cars Canada Ltd. spokesman noted
that while carbon fiber, magnesium and aluminum have shown
promise, their price tags can be intimidating to
Automotive steel for the most part is still relatively
cheap, with hot-rolled band, used for vehicle body panels,
costing an average of 23 to 27 cents per pound, according to
industry estimates, with high-grade steel about 10 to 30
percent more expensive. Aluminum, however, can cost upward of
$1 per pound, while magnesium is often above $2 per pound and
carbon fiber, in some cases, can cost four to eight times more
"While carbon-fiber is sexy, it is expensive, difficult to
work with and doesn't make sense for a mainstream car," the
Porsche Canada spokesman said, noting that the Mississauga,
Ontario, automaker's new Panamera four-door sedan optimizes
different grades of steel. The company also has targeted
aluminum use in its door skins and hood, with magnesium used in
its bumper carriers and door frames, but to a more limited
degree. "The way magnesium is used, because it's difficult to
work with and expensive, is something that I'd be surprised to
see in such a great extent in any other cars."
While lightweight metals might continue to grab the
spotlight, many auto executives expect some of the more notable
changes to be in size, not substance.
Several analysts believe that weight reduction, including
segment shift to different vehicles, will account for only
one-quarter of the overall fuel economy improvement and carbon
dioxide reduction required by 2020. The remainder will come
from powertrain changes, aerodynamic improvements,
low-rolling-resistance tires and battery improvements.
Parker expects to see more platform shifts from
body-on-frame-where a vehicle's body and bed are separate
components bolted on top of the frame-to unibody designs.
Verbrugge said he expects automakers to continue their focus
on smaller vehicles, which will reduce the volume of certain
materials required in manufacturing. He noted that the majority
of Chevrolet, Buick, GMC and Cadillac vehicles in coming years
will be cars and crossovers. "Trucks still are an important
part of our portfolio, but we expect they will largely return
to their original customers-those using them for work or
specific needs." he said. DARCY KEITH
Jamie Zachary contributed to this story.