CRASH-SAFETY and emissions regulations are forcing carmakers to adopt revolutionary new steel technologies. New models in development and due to arrive in 2002-03 all feature high-tensile steels and sophisticated welding and shaping techniques for steel parts.
Steelmakers naturally want automakers to go faster.
'Cars have to become more fuel efficient and safer in a few years,' says Rolf Vogel, managing director of Hoogovens Steel Strip Mill Products in the Netherlands.
However, he said, 'the car industry's thinking is evolutionary: all they need is proven technology.'
High-tensile steels have gained widespread acceptance among carmakers. Because they are thinner than regular steel of the same strength, they contribute to lighter cars. Other technologies, such as tailor-made blanks and hydroformed profiles, are not yet common.
Tailor-made blanks consist of different grades and thicknesses of steel, which are generally laser welded together by the steelmaker or a specialist partner.
The blanks are then stamped to make body panels and other parts that are thicker where they need strength and thinner where they don't. About 15 percent of European production car models use some tailored blanks.
Hydroformed parts are shaped by water pressure. Water is pumped into a steel pipe, which expands to fill the shape of the mold. Hydroformed parts can be lighter and stiffer and have better structural characteristics than parts that are molded or stamped.
Steelmakers say that the biggest single part that could be hydroformed would be a combined A-pillar, roof rail and C-pillar. No production car uses hydroforming for body structures yet.
'Everyone is working on this,' says Sander Prinsen, product manager at Hoogovens Steel. 'But production is only possible with specialist partners.'
Hydroformed tubular sections are already used in engine cradles and, in a simplified form, for exhaust systems.
Volkswagen is Europe's leading carmaker in the use of new steel technologies, according to Hoog-ovens.
The new Golf has 19 parts made with tailored blanks, accounting for 21 percent of the body-in-white's weight of 242kg.
Each carmaker has a different strategy for improving its use of new steel technologies.
'The steel industry is getting more involved in the structural development of new cars,' says Prinsen. 'But the process is slow and we have to build up trust.'
But Anneliek Waaijer, automotive project manager at parent company Royal Hoogovens, says carmakers want to keep control of the way steel technologies are used.
'As long as it is made of steel, they want do it themselves - it adds to the identity of the manufacturer,' she says. By contrast, 'for plastics and even aluminum, the car industry prefers to outsource.'
Therefore, the role of the steel industry has to be 'to develop new materials, advise on applications and offer engineering, such as welding technology,' says Waaijer. 'If possible, we will produce sub-assemblies, with specialised partners.'
Five years ago, says Prinsen, automakers preferred to outsource steel research. 'They left us free to take the initiative.'
The situation has changed since then. 'Now,' he says, 'they ... are developing their know-how for strategic reasons.'
Waaijer expects body panels and doors increasingly to be made out of the new, lighter steels or aluminum.
Steelmakers see aluminum as a threat, but one that they can overcome.
When Audi introduced its aluminum-bodied A8 in 1994, the steel industry realized 'we had to come up with some clear answers,' says Vogel. 'We have since proved that a car's structure can be made lighter and stronger with steel, and without the need for high investment.'
The Ultra Light Steel Auto Body consortium of 35 steel companies has developed a lightweight body-in-white, of which 90 percent is high-tensile steel.