A plasticity model with yield surface distortion for non proportional loading

Marc Louis Maurice François (1, 2)

1 FAST - Fluides, automatique, systèmes thermiques
2 LMT - Laboratoire de Mécanique et Technologie

In order to enhance the modeling of metallic materials behavior in non proportional loadings, a modification of the classical elastic-plastic models including distortion of the yield surface is proposed. The new yield criterion uses the same norm as in the classical von Mises based criteria, and a "distorted stress" Sd replacing the usual stress deviator S. The obtained yield surface is then “egg-shaped” similar to those experimentally observed and depends on only one new material parameter. The theory is built in such a way as to recover the classical one for proportional loading. An identification procedure is proposed to obtain the material parameters. Simulations and experiments are compared for a 2024 T4 aluminum alloy for both proportional and nonproportional tension-torsion loading paths.

Mots clés: constitutive behavior; elastic-plastic material

Domaines: Mécanique des matériaux [physics.class-ph]; Mécanique des matériaux [physics.class-ph]

Marc Louis Maurice François. A plasticity model with yield surface distortion for non proportional loading. International Journal of Plasticity, 2001, 17 (5), pp.703-718. ⟨10.1016/S0749-6419(00)00025-5⟩. ⟨hal-00453149⟩