Manufacturers Study Lighter Truck Materials

This story appears in the Aug. 31 print edition of Transport Topics.

Aluminum and steel makers, and at least one truck manufacturer, said they are working to design truck cabs and frames using lightweight materials that could reduce a tractor’s weight by 20% to 25%.

The Aluminum Association, the American Iron & Steel Institute and global truck maker Volvo AB all said that they have been engineering prototypes that could hit the road within 10 years, saving fuel and allowing more payload.

Randall Scheps, chairman of the Aluminum Association’s auto and light truck group, said advances in aluminum alloys have shown that the weight of a tractor and trailer could be cut by 3,500 pounds.

“What aluminum brings to these applications is a 40% to 45% weight-save versus steel, better corrosion performance, better resale value, great looks and design flexibility,” Scheps told Transport Topics.

However, representatives of some truck manufacturers raised questions about aluminum’s price and potential corrosion and strength problems when substituting aluminum for steel.

“Some new applications of aluminum that we are really excited about are in the area of frame rails and trailer rear headers,” Scheps said. “Tractor frame rails are almost 100% steel today, but there is a huge weight-save opportunity there. A 400-pound savings is not out of the question.”

Scheps said that while aluminum costs more than steel, fleets would be able to make up the difference within two years through greater fuel efficiency and increased load capacity.

Aluminum Association spokeswoman Kristin Tyll declined to comment on price.

“Every application is different, and the price of the aluminum used in the application depends on the specifics of alloy and processing needed,” she said.

Primary aluminum, the main traded form of the metal, sold for $1,884 per metric ton on the London Metals Exchange spot market on Aug. 26. Steel billets, the most commonly traded form of that metal, sold for $395 per metric ton.

David Anderson, director of the Automotive Application Council of the American Iron & Steel Institute, said his organization believes it can transfer lightweight, high-strength steel from the auto industry to heavy trucking.

“We’ve also been studying ways to cut weight in heavy trucking with advanced, high-strength steel, and we believe that we can cut the overall weight by 25% but with the same cost as traditional steel, making them much less expensive than aluminum-component trucks,” Anderson told TT.

Scheps and Anderson both said they have not yet brought their new alloys to truck manufacturers but plan to do so soon.

Truck makers said they were aware of research into lighter weight alloys and receptive to using them in their products if they did not detract from safety or performance.

Global truck maker Volvo AB, which owns Mack Trucks Inc. and Volvo Trucks North America, has a team working on a cab shell. The Volvo Technology group is working to cut weight from its current cab by 20% in 10 years. Other Volvo technology teams are working on reducing the weight of engines and major components.

Over-the-road sleepers from Volvo Trucks North America currently weigh between 17,000 and 18,400 pounds, Paul Badilita, new truck salesman at TEC of California, a Volvo dealer in Fontana, Calif., told TT.

Carl Fredrik Hartung, product area manager, Volvo Technology, told TT the main goal was “to improve fuel economy and reduce emissions of carbon dioxide.”

He said the project would involve substituting various lighter weight materials for current materials.

Volvo Technology is using computers to analyze hundreds of thousands of combinations before any actual prototype will be built.

“There are 160 parts in a cab ‘body-in-white,’ which is the basic cab steel structure, and you must investigate every change in every way possible,” Hartung said.

“To date, we have tested different grades of steel, aluminum, carbon composites, glass fiber-reinforced plastics and also magnesium,” Hartung said.

All research is being carried out at Volvo’s headquarters in Gothenburg, Sweden, but the results will be applicable to cabs produced by Volvo subsidiaries all over the world, he said. In North America, those are VTNA and Mack.

“Mack Trucks is fully aware of the new aluminum alloys and other new alloys,” Jerry Warmkessel, highway products marketing manager for Mack, told TT.

Tom Barkimer, Navistar Inc.’s chief engineer for materials and fastener engineering, said his company has not heard of the new alloys but would be interested in learning about it. Navistar makes International trucks.

“In general, we’re always looking for new materials, metals or nonmetals that can reduce weight, as well as new efficient designs that reduce weight,” Barkimer told TT.

However, he said that integrating aluminum into International truck cabs would be difficult.

“Our cabs are all-steel, and when you mix steel and aluminum, you have to isolate the two, because if the two metals are simply connected, it can form corrosion. So, when you join them, you have to isolate the connection with a sealer or a gasket,” he said.

“We did offer all-aluminum frame rails a few decades ago, but fleets reported a high failure rate with them, so they were discontinued,” Barkimer said.