Determining cyclic flow curves using the in-plane torsion test

A new method of determining cyclic stress-strain curves for characterizing kinematic hardening of sheet materials is introduced utilizing the in-plane torsion test and optical strain measurement. The test enables the simultaneous recording of multiple cyclic stress-strain curves with different amplitudes of plastic strain at load reversal in one single test and with one single specimen. Cyclic flow curves are obtained for DP600, DP800, DX54D, and AA5182, and compared with the Miyauchi shear test. Material parameters for a typical kinematic hardening model are determined. Multiple cyclic stress-strain curves result significantly different model parameters as obtained by a single cyclic curve.