Mathematical Model of the Semicrystalline Polymer Behavior Exposed to Uniaxial Tension with the Different Strain Rates

Abstract

The article presents results of uniaxial tensile testing the 2NT11-9 polyethylene (PE-100) for a wide range of the loading rates at the relatively low strain (< 15--20 %). It provides relaxation curves for various stress levels to analyze the short-term (transient) creep processes. The relaxation observation time during testing was 1 hour. The paper studies dependence of the residual strains in the material on the total strains obtained under direct loading. To describe the obtained experimental data, it proposes the constitutive relations that take into account the material strain-induced softening and its creep while maintaining a hypothesis of the small (linear) strains. A method for determining numerical values of the material proposed model behavior parameters is described in detail. The model elastic parameter values are determined from the equilibrium tensile curve, and the viscous parameters are determined from the relaxation curves. The paper shows that the constructed model uses a single set of the numerical parameter values determined in this way, and makes it possible to describe satisfactorily the material uniaxial stress-strain curves at the various strain rates. In general, the presented material model behavior could be applied to analyze short-term strength of the products made from the semicrystalline polymers

Please cite this article in English as:

Semenov V.K., Petrikov E.K. Mathematical model of the semicrystalline polymer behavior exposed to uniaxial tension with the different strain rates. Herald of the Bauman Moscow State Technical University, Series Natural Sciences, 2025, no. 6 (123), pp. 21--37 (in Russ.). EDN: WWTKHL

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