New technology for environment-friendly cars

A "clever" new technology from researchers at Hiroshima University can help engineers develop safe, lightweight and environment-friendly cars that emit less carbon dioxide.

Dr Komgrit Lawanwong and colleagues have engineered some subtle refinements to metal forming techniques that allowed them to prevent a difficult problem called "springback".

High-strength steel is widely used in automotive components to help them withstand impacts without increasing their body weight.

This has potential environmental benefits as lightweight cars burn less fuel and, therefore, have lower emissions.

The most serious problem in the press-forming of these steel sheets is their extremely large 'springback' -- which is the tendency of a metal to return to its original shape after compression or stretching.

A simple example of springback is the small gap that will remain if you fold a metal sheet in the middle with your fingers and then release it.

"The problems become particularly acute when high-strength materials are used so a new technique to eliminate springback is urgently needed in the stamping industry," said Dr Komgrit.

The new method delivered the best result for the springback angle -- almost zero -- together with a flat bottom.

"This method is a useful way to eliminate the springback of high-strength steel in press forming," the authors noted in the Journal of Materials Processing Technology.