The Future-Looks Light

Automotive Industries,  Oct, 1999  by Dale Jewett

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When automakers need to loose weight, aluminum remains a prime -- but expensive -- choice.

Seven years ago, as Ford Motor Co. engineers were developing a new design for the Taurus for the 1996 model year, they chose to stamp the trunk lid out of aluminum. Not only did the material save weight, it helped burnish the leading-edge technology image Ford sought for its mid-size sedan.

The team that developed the redesigned 2000 Taurus was challenged by chief engineer Dave Marinaro to make the vehicle more useful to buyers, without increasing weight or cost. In order to satisfy those conflicting requirements, the new Taurus wears a steel decklid.

"It wasn't a hard choice. Steel was one-fifth the cost of aluminum," notes Marinaro.

The 1999 model year was the best ever for the aluminum industry -- each North American-built vehicle carried an average of 248 pounds of aluminum, more than 3.8 billion pounds overall, according to Ducker Research Co. And for the first time, light trucks carried a higher average content of the lightweight metal than cars.

The 2000 model year brings even more feathers in the industry's cap: the introduction of aluminum-intensive vehicles from BMW (Z8 roadster), Honda (the S2000 roadster and Insight hybrid vehicle) and Mercedes-Benz (the full-size CL coupe). And Audi brings its all-aluminum AL2 concept car into mass production, as the A2. (See p.85.)

But without a cataclysmic event, even the aluminum industry knows that its share of the automotive market will grow slowly over the next four to five years, driven mainly by part-for-part substitution for steel.

"The number one roadblock to aluminum in the auto industry today is cost," says Subi Dinda, director of advanced materials for DaimlerChrysler. "It's hard to justify a cost of $1.50 to $1.75 a pound for sheet aluminum, when sheet steel costs around 21 cents a pound."

Despite the cost penalty, automakers continue to push ahead with new applications for aluminum:

Underneath the hood of the Chevrolet Impala and Monte Carlo rests an extruded aluminum engine cradle that is 37% (26 pounds) lighter than if it had been rendered in steel. The cradle is also more rigid and dimensionally accurate, say engineers.

General Motors engineers also used aluminum to reduce the weight of the liftgate for the redesigned Chevrolet Tahoe/Suburban and GMC Yukon/Yukon XL.

The new Lincoln KS sedan contains more than 375 pounds of aluminum, including the hood, decklid, front fenders, suspension components, brake calipers and powertrain.

The Mercedes-Benz CL, which reaches the U.S. market in December, uses aluminum for its hood, roof and rear quarter panels -- part of a matrix of materials the automaker used to trim more than 500 pounds from its flagship coupe.

And the lightweight metal is assured of playing a key role in the future, particularly in the prototypes being produced for the U.S. Partnership for a New Generation of Vehicles "Supercar" project, aimed at designing an 80-mpg midsize sedan. Ford's P2000 entry will have more than 730 pounds of aluminum, about 35% of its 2,000-pound curb weight.

Yet with the notable exception of the high-volume Suburban/Yukon, Ford's use of aluminum for the F-Series pickup truck, and Audi's new A2, most vehicles that contain lots of aluminum continue to be low-volume projects, due to the cost. Automakers and aluminum companies are trying to find ways to mitigate the cost factor.

How To Reduce Cost?

Last November GM signed a 10-year price agreement with Alcan Aluminium. The deal is aimed at stabilizing, for GM, the material's commodity price fluctations. It also includes increased cooperation among engineers of the two companies.

"Our goal was to guarantee that we have a steady supply of aluminum that can be used in everything from wheel covers to powertrains," says Dennis Minano, vice president of environment and energy for the automaker.

GM also has agreed to buy all the recycled aluminum from a plant in Zilwaukee, Mich., in a deal valued at more than $1 billion during the 13-year life of the contract.

Further price relief could be the ultimate result for the auto industry from a wave of consolidation that swept through the aluminum industry this past summer. Chief among those combinations was Alcan's merger with two European aluminum firms, and Alcoa Inc.'s buyout of Reynolds Aluminum.

"The mergers are absolutely good news for the auto industry," says Richard Evans, president of Alcan Aluminium Corp., the Canadian company's U.S. subsidiary, and chairman of the Aluminum Association. "As larger companies, they will be able to concentrate more resources on developing new materials and processes for automakers."

Lower prices, alone, won't automatically give the aluminum industry the kind of boost it seeks from automakers. Aluminum suppliers are locked in a battle with steel and plastics companies for the hearts and minds of automotive engineers, and recently they have moved their education and public relations efforts to a higher level.