Outokumpu Nirosta GmbH (Krefeld, Germany):

Lindner S., Dr. Eng., Mag. Sc., Head of Automobile Designing Dept., e-mail: stefan.lindner2@outokumpu.com

The properties of new material (Mn–Cr steels) are presented. Such steels were developed for different yield strength values (500, 800 and 1000 MPa) and they can be classified as ultra high strength steels. At the same time they are characterized by high value of relative elongation it allows to manufacture automotive details and components with more complicated geometrical shape and to absorb large energy volume during impact. These steels are commercially available at present time as sheets with thickness 0.5–4.0 mm and width 1250 mm, and the work in direction of spreading this dimension range is continuing actively. All steels of the developed series are now subjected to the procedure of acceptance for usage by different automotive producers and the process of preparing the material specification. Owing to their well-balanced mechanical and technological properties, structure and strengthening mechanisms, the TWIP Mn–Cr steels are able to provide innovative lightweight constructions for shock-proof and safe transportation vehicles. The steels are also characterized by increased capacity for power absorption during shock load and by welding ability. They also allow to realize the prospective ecological and social requirements for lightweight materials.

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