MODELING LARGE-STRAIN MULTIAXIAL EFFECTS IN FCC POLYCRYSTALS

Results from compression, torsion, compression-followed-by-torsion and torsion-followed-by-tension experiments are presented for 304L stainl ess steel at room temperature. Very distinct stress state-dependent be havior is observed such as a lower von Mises equivalent stress level f or pure torsional loading compared to uniaxial compression at the same uniaxial equivalent strain. Secondary axial effects are measured duri ng torsional loading as well. Pertinent inelastic deformation processe s are discussed and explanations are offered for the observed stress s tate-dependent phenomena, including morphological changes of both text ure and deformation substructure. We review basic micro- and macro-sca le model frameworks for modelling large deformation stress-strain beha vior. Efforts to capture stress state-dependent phenomena using such f ormulations are presented. A macroscale model framework is proposed wh ich uses the third invariant of overstress, J(3), to delineate stress state effects. Copyright (C) 1996 Elsevier Science Ltd