This paper is focused on determining the stress-strain curve of sheet metal by bulge test. The first part of the paper describes a methodology recently developed by the authors, for effective and accurate determination of stress-strain curve by bulge test. This methodology is based on the continuous measurement of hydraulic pressure and polar height of the specimen during the test, and on an analytical approach that is able to take into account the non-uniformity of the specimen thickness in the meridian section during bulging. Further the FE -simulation of bulge test is used in order to evaluate the accuracy of the hardening law obtained using the new methodology. This evaluation is done by comparison between the FE- simulation results and experimental data. As comparable results were used the distribution of the specimen high and the distribution of the wall thinning as function of the position in the meridian section. The experiments were performed on samples made from rolled steel sheets DC04 using a 3D optical measurement system ARAMIS. By comparison of the results a good agreement between finite element simulation data and experimental result was found.

Key words: Bulge test, Analytical approach, Stress-strain curve, Thickness reduction, FE-Simulation.

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