Analysis of Neck Propagation in Polymeric Fibres Including the Effects of Viscoplasticity

Abstract

The effects of material strain-rate dependence on necking and neck propagation in polymeric fibres are analyzed. Using a finite element scheme together with an elastic-viscoplastic constitutive model the entire load-deformation histories of round specimens are computed. Stress-strain distributions as well as the evolution of the specimen profiles are given at various stages of the axisymmetric stretching process. Comparisons with rate-independent response are also presented.