Belgium: Study highlights aluminium benefits

According to a study conducted by the University of Aachen in Germany, using aluminium in key automotive components can safely reduce vehicle weight by as much as 40%, compared to only 11% for high-strength steel.

The study, conducted by the Institut fur Kraftfahrzeuge at the University of Aachen for the European Aluminium Association （EAA）, analysed 26 automotive components to assess the further potential or limits of weight reduction for both steel and aluminium. The EAA represents the European aluminium industry from alumina and primary production to semi-finished and end-use products, through to recycling.

According to Randall Scheps, chairman of the Aluminum Association's Aluminum Transportation Group （ATG） and Alcoa's director of ground transportation: “Aluminium use in the automotive sector has increased steadily for the past four decades; however this new study makes clear the environmental and safety advantages of the high-strength, low-weight material have yet to be fully realised. This study combined with other data on the benefits of aluminium suggest a total of about 525 pounds of additional weight savings, which could result in 2.7 more miles per gallon or a nearly 10% further improvement in fuel economy over a typical auto today. This can be done while maintaining – if not further improving – vehicle safety."

Members of the ATG include: Alcoa; Novelis; Rio Tinto Alcan; Aluminum Precision Products; Kaiser Aluminum Corporation; and Sapa Group.

The study found that using aluminium could result in significant weight savings for the analysed components, ranging from 14 to 49%. Using a state-of-the art steel reference car, the maximum weight reduction potential of aluminium in car bodies was approximately 40%.

Weight reduction potential using high strength steel was found to be limited to only an additional 11%. According to the study, the reason the potential weight reduction using high strength steel is so small, is that nearly 40% of the parts analysed simply cannot be made thinner regardless of the grade of steel used. If high strength steel were to be used to lightweight these parts, their stiffness would actually be reduced and the car's performance would suffer, whereas, aluminium could be used without reducing stiffness or causing the car's performance to suffer.

The study also concluded that the potential for automotive aluminium lightweighting varies and options include maintaining a steel body with aluminium closures, hang-on and mounting parts, hybrid or multi-material designs for the body and full aluminium body.

Scheps adds: "Lightweighting the world's overall transportation fleet through the use of aluminium has the potential to reduce greenhouse gas emissions by nearly 660 million tons annually, or 9% of global, transportation-related greenhouse gas emissions."