Non-quadratic yield criterion for orthotropic sheet metals under plane-stress conditions

The paper presents a new yield criterion for orthotropic sheet metals under plane-stress conditions. The criterion is derived from the one proposed by Barlat and Lian (Int. J. Plasticity 5 (1989) 51). Three additional coefficients have been introduced in order to allow a better representation of the plastic behaviour of the sheet metals. The predictions of the new yield criterion are compared with the experimental data for an aluminium alloy sheet and a steel sheet.