DETERMINATION OF MATERIAL PARAMETERS OF SHEET METALS USING THE HYDRAULIC BULGE TEST

Hydraulic bulging experiments are performed in order to evaluate the mechanical parameters of cold rolled steel (DC04) and aluminium alloy (EN AW 6016-T4) sheet materials. The biaxial yield stresses, and the biaxial anisotropy coefficients are derived from the biaxial stress-strain curves and the ratio between the strains in the transverse and in the rolling direction, respectively. The mechanical parameters resulted from the bulge test in combination with the results from the tensile tests are used to determine the yield loci of the two materials. The effect of the number of input parameters on the capability of the BBC 2008 yield criterion to predict the yield locus is also discussed in the paper.