Automobile bodies: Can aluminum be an economical alternative to steel?

Although the use of aluminum in cars has been increasing for the past two d ecades, progress has been limited in developing aluminum auto bodies. In fa ct, most aluminum substitution has come in the form of castings and forging s in the transmission, wheels, etc. Car manufacturers have developed allumi num cars with two competing designs: conventional unibody and the spacefram e However aluminum is far from being a material of choice for auto bodies. The substitution of aluminum for steel is partly influenced by regulatory p ressures to meet fuel efficiency standards by reducing vehicle weight, and to meet recycling standards. The key obstacles are the high cost of primary aluminum as compared to steel and added fabrication costs of aluminum pane ls. Both the aluminum and the automotive industries have attempted to make aluminum a cost-effective alternative to steel. This paper analyzes the cos t of fabrication and assembly of four different aluminum car body designs,m aking comparisons with conventional steel designs at current aluminum price s and using current aluminum fabrication technology. It then attempts to de termine if aluminum can be an alternative to steel at lower primary aluminu m prices, and improved fabrication processes.