The Shape Corporation is an American automotive component manufacturer that has developed a bumper made of advanced high strength steel, but which weighs only roughly the same as a much more expensive aluminium bumper. The new bumper comprises two members, one of which is roll formed and the other is pressed. The two are joined together and are provided with integral reinforcement. The automotive industry has already shown keen interest.

The Shape Corporation has developed its new patented bumper to meet the automotive industry’s demand for lighter weight bumper systems that meet both performance and safety requirements.

“Our customers demand lighter bumpers, but without compromising the properties of the roll-formed bumper,” explains David Heatherington, Head of R&D at the Shape Corp. of Grand Haven, Michigan. “We therefore decided to undertake development work which yielded a hybrid bumper. In this hybrid concept, we combine the best of two production methods – roll forming and pressing.”

Specialist in roll forming

Shape is well-established as a subcontractor to the American automotive industry and has become known as a specialist in roll forming, in which the company has been highly successful. The demand for lighter components has led the company to test different bumper materials, such as aluminium. This met the weight requirement, but the costs were too high.

The hybrid concept developed by David Heatherington together with his colleagues Scott Glasgow and Bruce Lyons is totally new, achieving a breakthrough by using the properties of ultra-high strength steels,whilst combining different methods of forming during production.

The bumper that has been awarded second prize comprises two members, one of which is roll-formed and the other is pressed. The two members are joined together into a closed profile, the cross-section of which varies along the bumper length with the material changing around the cross section. The bumper thus has optimum weight and performance, whilst using both the type and amount of material efficiently. The rear pressed member is created in only one operation with reinforcements and mountings as integral parts.

High-speed collisions

“The advanced high strength steels we are using meet the demands imposed for withstanding high-speed collisions, and the more advanced the steel, the better the protection,” explains David Heatherington. “No other material would have enabled us to achieve our objectives.”Among the other benefits named by David Heatherington is that the company’s existing equipment can be used for production, negating the need for any new investment.

“The hybrid concept has also given us greater scope for designing the bumper to suit different car models,” continues David Heatherington. “We have succeeded in developing a bumper concept that no one believed would have been possible. The weight of the bumper is at least as low as an equivalent aluminium bumper and the advanced high strength steels used provide excellent crashworthiness.”

Text: Jan Tannefors No 1 2006