High environmental standards and improving safety are two of the major concerns of today's car manufacturers.

In order to reduce carbon dioxide emissions from vehicles, and make them more environmentally sustainable, car manufacturers must dramatically reduce vehicle weight. As the weight mostly derives from steel, the dilemma is how to do that without compromising passenger safety.

The solution

Stainless steel shows powerful potential for weight reductions. So, for the first time, three of the world’s largest stainless steel producers including Outokumpu and six major car manufacturers have joined forces to present stainless as a viable alternative for structural components in cars.

Using high-strength stainless steel, rather than ordinary steel, car parts can be made considerably thinner and lighter, while actually improving safety. Other benefits of stainless steel for car manufacturers include excellent fabricability and unique hardening behavior during cold-forming processes.

The result

Under the umbrella of the Next Generation Vehicle research project (NGV), the research partners are developing new tools that can be used by car manufacturers to design and fabricate structural parts out of stainless steel.

The B-pillar of a car body redesigned using
stainless steel in its core.

After project commencement in early 2005, the partners collected data to produce automotive stainless steel design guidelines. They then applied those guidelines in actual product design. Using the B-pillar (a key structural member of a car body) from Volvo S40 as a benchmark, they came up with two different designs, some 20 percent lighter than the conventional pillar.

When crash-tested, the behavior of stainless steel performed very well, although it reacted differently from ordinary steel. The work was used to validate adapted forming and crash simulations.

The future

The results gained in the project were summarized at a press conference in Frankfurt. Virtual design tools will be available for the auto industry by the end of the year. The goal of the project in its final months is to fine tune the tools and establish them as a permanent part of car manufacturers’ toolkits.

Eric Sörqvist, an Outokumpu expert in stainless steel for automotive applications, summarized the significance of the NGV project as broadening the possibilities of stainless outside the traditional uses based on corrosion resistance properties, making use only of the material’s mechanical properties.