Modelling finite deformation stress-strain response during loading-unloading of polyethylene over a wide range of crystallinities

摘要

Experimental observations are reported on the finite deformation stress-strain response during loading-unloading of polyethylene materials covering the range of crystal volume fractions 0.15-0.72. Hyperelastic-viscoplastic constitutive equations, based on a two-phase interpretation of the microstructure, are derived. It is shown that the constitutive model adequately describes the experimental observations under loading-unloading conditions.