Since the 1970s, governments have enacted legislation, which varies from country to country, with some focusing on emission levels and others on fuel economy. In the U.S., CO2 emissions and the Corporate Average Fuel Economy (CAFE) standards for mileage are the key drivers of weight reduction. Figure 1 illustrates these objectives and the pressure automotive manufacturers face today.
Weight-reduction initiatives have taken many forms over the last 35 years and include redesigning of suspension systems, designing smaller and more powerful engines, and integrating high-strength steel and aluminum over other heavier materials. This article will review the recent advancements made integrating aluminum-intensive structural castings into automobiles, developments in casting and will focus on the new heat-treatment technologies available to meet the increasing demands of productivity and quality.