**About the Editor**

**Bernd-Arno Behrens** studied mechanical engineering at the University of Hannover and received his doctorate in 1997 in the field of bulk metal forming. Subsequently, he took over a leading position in the industry. Since October 2003, he has been director of the Institute of Forming Technology and Machines (IFUM). In addition, in 2004 he was appointed spokesman of the board of the Material Testing Institute for Materials and Production Technology (MPA) in Hannover. In 2005 he also assumed the function of managing partner of IPH—Institut fur Integrierte ¨ Produktion Hannover gemeinnutzige GmbH. He is, among others, speaker of the Collaborative ¨ Research Center 1153 "Tailored Forming". He is a member of the Scientific Council of the AIF and the Arbeitsgemeinschaft Umformtechnik. His research interests include sheet and bulk metal forming technology and machines, machine development (drives, actuators, control), thermo-mechanical material characterization and FE simulation.

## **Preface to "Hybrid Bulk Metal Components"**

In recent years, the requirements for technical components have steadily been increasing. This development is intensified by the desire for products with a lower weight, smaller size, and extended functionality, but also with a higher resistance against specific stresses. Mono-material components, which are produced by established processes, feature limited properties according to their respective material characteristics. Thus, a significant increase in production quality and efficiency can only be reached by combining different materials in a hybrid metal component. In this way, components with tailored properties can be manufactured that meet the locally varying requirements. Through the local use of different materials within a component, for example, the weight or the use of expensive alloying elements can be reduced.

This Special Issue includes research articles on investigations considering the production of hybrid components, most of which were prepared within the framework of Collaborative Research Center 1153 ("Process Chain for Manufacturing of Hybrid High Performance Components by Tailored Forming", www.sfb1153.de) or by international scientists.

The aim of this Special Issue is to cover the recent progress and new developments regarding all aspects of hybrid bulk metal components. This includes fundamental questions regarding the joining, forming, finishing, simulation, and testing of hybrid metal parts.

> **Bernd-Arno Behrens** *Editor*
