A New Method of Predicting the Formability of Materials
Published February 1, 1972 by SAE International in United States
Annotation of this paper is available
The paper presents a new method, based on standard laboratory cup tests, for predicting the formability of materials; in the example provided, the forming potentials of four new materials are shown.
The properties of stretchability and drawability, which are the principal factors defining a material's forming limits, may be assessed using the Olsen spherical cup test and the Swift flat-bottomed cup test. In the shape analysis procedure described, the minimum amount of deformation needed to fix a desired shape is determined. Then necessary adjustments to tooling for optimum sheet metal usage are made based on calculations from a new type of chart showing stretch forming ratio and draw forming ratio, providing a comparison of the formabilities of a number of materials. It is shown that, in the absence of reliable cup testing data, values can be obtained using laboratory tensile testing results; this is possible because computer-determined correlations of certain tensile parameters to standard cup test results have been made.
CitationKasper, A. and VanderVeen, P., "A New Method of Predicting the Formability of Materials," SAE Technical Paper 720019, 1972, https://doi.org/10.4271/720019.