Aluminum R&D for Automotive Uses and the Department of Energy's Role

The use of aluminum in automotive applications is expanding. Aluminum offers a lower-weight alternative to steel, potentially increasing the efficiency of vehicles. However, the application of aluminum has been only in select areas of use, most notably cast aluminum in the engine, transmission, and wheels. Other areas offer the potential for growth that could significantly expand the amount of aluminum used in vehicles. Cost is the main barrier to increased aluminum use. Related to cost are aluminum production technologies that are not yet advanced enough to produce aluminum components at low enough price points for aluminum to compete with traditional automotive materials. Today's technologies require higher-priced alloys to be used for the components (e.g., closure panels), or have higher costs for needed processes (e.g., welding). In addition, new designs (e.g., spaceframes) are not well established for widespread use. R&D efforts are continuing to close these gaps. The U.S. Department of Energy (DOE) is helping to fund certain R&D projects that could provide breakthroughs in lowering costs for aluminum. This paper describes the current state of aluminum applications in vehicles, including its market penetration and opportunities. It also examines the cost structure of aluminum--from mining to final component use. By examining these factors, an evaluation of whether current aluminum technology is mature enough for specific applications is made. Each major aluminum processing step is then reviewed to identify major cost or technology barriers as well as R&D needed to respond to those barriers. For each step, the report provides a discussion of DOE's programmatic role in reducing cost and technological barriers and DOE's Light Weight Materials program support for the overall R&D needs in the industry. The evaluation embodied in this report finds that aluminum has successfully penetrated the automotive market, largely (>75%) in the form of castings. Aluminum sheet of the proper alloy is still too expensive to penetrate significantly except for components where lower weight has extra value (e.g., large hoods or deck lids). The cost of auto body sheet averages above $1.30/lb, 30% above what the auto industry has said is required for economic competitiveness. Further research is needed to either lower the cost of the alloys currently used for body sheet, or to develop methods to use less expensive alloys. Joining technologies need to be improved to lower their cost while improving quality. Extruded components have potential but will make the most significant contribution if spaceframe designs are developed for high-volume automobile markets. Aluminum has the potential to significantly reduce the weight of vehicles, improving fuel efficiency while maintaining other desirable attributes. Federally funded research contributes to this goal.