A phenomenological elastoplastic model for porous metal fiber sintered sheets

Metal fiber sintered sheets (MFSSs) are a type of layered open cell porous materials and are transversely isotropic. Their stress–strain responses to uniaxial tension and compression and simple shear loading in different directions (i.e., in the in-plane and transverse directions) were measured. A set of characteristic stress and strain was defined and employed to formulate an elastoplastic constitutive model for the infinitesimal deformation of MFSSs subject to monotonic proportional loading. The elastoplastic potential in the constitutive model was calibrated with the measured stress–strain responses in terms of the defined characteristic stress and strain, without a need to know the yield surface and its evolution a priori. A successful application of the developed model to the multiaxial mechanical responses of MFSSs was demonstrated.