Advanced materials are essential for boosting the fuel economy of modern automobiles while maintaining safety and performance. Because it takes less energy to accelerate a lighter object than a heavier one, lightweight materials offer great potential for increasing vehicle efficiency. Replacing cast iron and traditional steel components with lightweight materials such as high-strength steel, magnesium (Mg) alloys, aluminum (Al) alloys, carbon fiber, and polymer composites can directly reduce the weight of a vehicle’s body and chassis by up to 50 percent and therefore reduce a vehicle’s fuel consumption. A 10 percent reduction in vehicle weight can result in a 6%-8% fuel economy improvement.
Materials Technologies: http://www1.eere.energy.gov/vehiclesandfuels/technologies/materials/index.html