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parts with plex geometry. However, the mechanical properties of these parts often do not meet the requirements concerning the mechanical properties (. endurance strength and ductility). A promising alternative has to be seen in ponents that are manufactured by forming processes. The parts manufactured by this technology are characterized by advantageous mechanical properties and finegrained microstructure without pores [1]. However, a widespread use of forming technologies for the processing of magnesium alloys is restricted because of insufficient knowledge about the forming technologies and suitable process parameters that have to be applied [2,3].Automotive body constructions offer a great potential for the application of magnesium sheet metal ponents.In general, the automotive body pletely consists of sheet metal parts and represents a share of about 25% of the entire vehicle mass. Therefore, the substitution of conventional sheet materials by magnesium sheets would lead to essential weight savings in this application.2. Plastic material properties of magnesium sheetsMagnesium alloys show a limited formability at room temperature. This results from the fact that the hexagonal crystal structure and the low tendency to twinning only allow limited deformations. The differently orientated crystallites only show a deformation on the individual base slip plane, which leads to a mutual slip hindrance [4, 5]. A considerable improvement of the forming qualities can be achieved by applying temperature. The considerable increase in formability that occurs in the temperature range from 200 to2258C (depending on alloying position) was investigated by Siebel [6]. The reason for this effect was found in the thermal activation of pyramid sliding planes in the hexagonal structure [7]. . Influence of forming temperature on flow stressA detailed evaluation of the deformation properties of magnesium sheets requires the determination of the material’s characteristic values like anisotropy or