New stainless steels offer greater car safety
New research has highlighted the benefits of using new types of special steels to build the superstructures of vehicles. The work was carried out at the Technical Research Centre of Finland (VTT) and the Ford Research Centre. Stainless steel is a ferrous (iron) alloy which is prized for its resistance to corrosion. By varying the proportions of other elements, such as chromium and nickel, in the alloy, metallurgists can alter the properties of the resulting metal. For example, adding carbon to the mix results in a harder metal, while adding nickel makes the metal less brittle. The new types of steel have a lower chromium and nickel content, which makes them cheaper than conventional stainless steel. In addition, the high durability of the materials, combined with the hybrid welding/adhesive joining techniques developed by the VTT, means maintenance costs are lower. Tests carried out by the researchers indicate that vehicle superstructures made using extra formable austenitic steels offer higher safety in crash collisions than structures made using conventional materials. Furthermore, the fact that safety requirements can be met at a lower weight with these new steels gives them a competitive edge over other materials. When the vehicle reaches the end of its life, the new steels can be easily recycled to give high quality raw materials. While heavy duty vehicles, such as ships, trains and buses, will benefit most from using new steels, it is likely that they will become common in top-of-the-range cars within a few years. According to the VTT, further research should reveal which other industries could benefit from the use of these new types of steel.
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