Abstract: This paper is aimed at developing an elasto-plastic constitutive model for polyc-rystalline materials. The model is an energy-equivalent system composed of extensivecompressive components well-oriented and distributed uniformly in the 3-D space to simulate how the mic-rostructures of materials store and dissipate energy during deformation and slippage. The components are extended/compressed compatibly with the overall strain and each of them undergoes its own elongation history dependent on its orientation....