Determination of forming limit diagrams - a new analysis method for characterization of materials' formability

This paper introduces a new analysis method for characterization of materials' formability independent of individual expertise. Therefore forming limit diagrams (FLDs) are determined using the Nakazima method. Investigations on the influence of the analysis method and the failure criterion in detail will be presented. The new analysis method avoids misinterpretation of the forming limits of any material and the FLD. The forming behavior of materials has to be recorded with a frequency up to 20 Hz, in order to detect the forming limits within a sequence of pictures from onset of necking to failure by cracking.