The average use of AHSS in car body design has increased significantly over the past 20 years. This growth is not only an average mass growth, but the variety of available grades and property combinations increase, thus supporting fit-for-purpose options for lightweight design. Numerous ideas for future implementation of the so called 2nd and 3rd generation AHSS are proposed. Currently, the concepts mainly focus on the improvement of strength AND ductility as the main drivers for lightweight design. Future concepts have to envision more than these two properties. In particular, formability is presently not well defined as it depends on the applied specific forming process during car manufacturing and, hence, requires different properties, for example, distinguishing local and global formability measures. This extends the known materials concepts to new further dimensions such as uniform elongation, n-value, stretch-flangeability, bending angle, hydrogen embrittlement. A new generation, referred to as "Generation 4.0" follows 3rd generation AHSS which, in turn, opens the manufacturers a new dimension for lightweight design of future vehicles with the use of highly sophisticated materials with exceptional tailored properties, where "tailored" regards to the carefully adjusted overall materials' properties, instead of the spatially varying, as commonly used to describe "tailored blanks".

Die komplexe Technik heutiger Kraftfahrzeuge und Antriebsstränge macht einen immer größer werdenden Fundus an Informationen notwendig, um die Funktion und die Arbeitsweise von Komponenten oder Systemen zu verstehen. Den raschen und sicheren Zugriff auf diese Informationen bietet die Reihe ATZ/MTZ-Fachbuch, welche die zum Verständnis erforderlichen Grundlagen, Daten und Erklärungen anschaulich, systematisch, anwendungsorientiert und aktuell zusammenstellt.Die Reihe wendet sich an Ingenieure der Kraftfahrzeugentwicklung und Antriebstechnik sowie Studierende, die Nachschlagebedarf haben und im Zusammenhang Fragestellungen ihres Arbeitsfeldes verstehen müssen und an Professoren und Dozenten an Universitäten und Hochschulen mit Schwerpunkt Fahrzeug-und Antriebstechnik. Sie liefert gleichzeitig das theoretische Rüstzeug für das Verständnis wie auch die Anwendungen, wie sie für Gutachter, Forscher und Entwicklungsingenieure in der Automobil-und Zulieferindustrie sowie bei Dienstleistern benötigt werden.

Applying a specific roughness on steel sheets, to ensure paintability and sufficient lubrication, is a crucial point for the metal forming processes. Due to the strength of high manganese HSD® steels (X70MnAlSi 15-2.5-2.5), special actions are necessary to obtain the required roughness. At Salzgitter Mannesmann Forschung GmbH skin-pass rolling experiments on high manganese HSD® steels with different PRETEX® textured work-rolls were performed to investigate the influence of roll-surface-texture and skin-pass rolling force on the roughness transfer. The roughness and texture parameters of the steel sheets and roll surfaces were determined using optical confocal microscopy measurements. It is clearly shown that the work-roll surface texture has a major influence on the roughness transfer from work-rolls to steel sheet surfaces.

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