Application of viscoelastic-plastic model in blended yarn

Abstract

This paper investigates the mechanical properties of a blended yarn and its correlation with the characteristics of constituent yarns of different materials. Each yarn’s creep and stress relaxation tests are curves fitted to a six-element constitutive model. The results show that the higher the chemical fiber content in the yarn, the better the plastic properties. The experimental data fit the six-element model with 99% confidence. Compared with the commonly used viscoelastic Burgers and Ering models, the six-element model has a much more precise forecasting ability. Within the scope of this study, the ratio of yield stress to initial stress under different stress conditions calculated from the same yarn test is similar, and the ratio is only related to the blending ratio of polyester-cotton blended yarn. In yarns with strong plasticity, this ratio can reflect the proportional relationship between plastic deformation and elastic deformation in relaxation experiments.