EDITORS: The complete report is available to reporters at no charge from the Office for the Study of Automotive Transportation, (313) 764-5592.

ANN ARBOR—In their quest to build affordable vehicles that meet customer demands and government regulations, North American automakers will face stiff challenges in selecting automotive materials in the next decade, according to a University of Michigan forecast.

” The material selection process includes a variety of often conflicting factors,” say Brett C. Smith, a researcher with the Office for the Study of Automotive Transportation at the U-M Transportation Research Institute, and Michael V. DiBernardo, a retired General Motors Corp. executive. ” The two factors rated as most important—cost and weight—are an excellent example of such conflict.”

Their report on automotive materials is part of the eighth annual U-M Delphi Forecast and Analysis of the North American Automotive Industry, which polls more than 300 automotive experts on trends in materials, technology and marketing through 2005.

While the auto industry has traditionally relied on heavier, but less costly materials, such as cast iron and steel, the pressure to reduce the weight of automobiles for better fuel economy continues to increase, the researchers say.

” The industry is looking more closely at low-weight/higher- cost materials,” they say. ” Since this cost-weight dilemma will continue for at least the next decade, it is likely that those solutions that reduce weight while effectively addressing the cost issue will be the winners.”

According to the forecast, average vehicle weight is up slightly in recent years, but is expected to decrease by 10 percent by 2005, thanks in part to more stringent Corporate Average Fuel Economy (CAFE) regulations.

” Serious weight reduction must include either significant downsizing, which is unpopular with the customer, increased use of lightweight materials, which is costly, or some combination of both,” Smith and DiBernardo say. ” The challenge will be for the industry to improve design of today’s materials and develop cost- effective applications for higher-cost, lightweight materials.”

Although auto industry experts rate steel above lightweight plastics and aluminum in the raw material cost, component processing, assembly and vehicle disposal stages, as CAFE increases, so will the move toward lighter materials, they say.

For example, as a percentage of material content of passenger cars, the use of aluminum and plastics is projected to increase by as much as 25 percent and 15 percent, respectively, if CAFE is 35 miles per gallon in 2005. Likewise, the use of steel is expected to decrease by 10 percent with a CAFE of 35 mpg.

The researchers say that steel will continue to be the dominant material in frame construction, body panels, suspension control arms and springs in the next decade. However, aluminum will be used for most cylinder heads and an increasing number of engine blocks by 2005.

Finally, in addition to higher production costs associated with lightweight materials, automobile manufacturers also are faced with the challenge of recycling such materials as plastics/polymers, they say.

While currently about 75 percent (by weight) of each vehicle is recycled through the removal of resaleable parts, fluids and metals, the remaining 25 percent—comprised mostly of plastics—ends up in landfills.

” Even though the automobile is one of the most recycled consumer products, the industry faces continuing pressure to further increase recyclability,” Smith and DiBernardo say. ” However, the lack of an economically viable recycling infrastructure will continue to prevent large-scale plastics recycling, as well as technology to separate waste into the various components.”