Chinese Journal of Polymer Science

, Volume 37, Issue 2, pp 178–188 | Cite as

Rheological Properties of Polyamide: Experimental Studies and Constitutive Modeling

  • Cyprian SuchockiEmail author
  • Rafał Molak


This work is focused on simulating the rheological effects in polyamide. An experimental study is carried out in order to assess such features of polyamide as: the hysteretic behavior, the strain rate dependence, and the stress relaxation. The material response in tension is investigated. Digital images correlation method (DIC) is employed in order to measure the material compressibility. A newly developed constitutive model, which was previously used to simulate the mechanical response of polyethylene subjected to moderate strains and compressive loadings, is applied to capture the large strain, inelastic behavior of polyamide in tension. The gathered experimental data are utilized to determine the values of constitutive constants of viscoelasticity and plasticity, which describe the rheological properties of polyamide. The determined material parameters are included in the text. Different strategies for evaluating the material parameters are discussed. The proposed constitutive equation is implemented into the finite element (FE) system, ABAQUS, by taking advantage of the user subroutine UMAT, which allows to define custom material laws. Some exemplary FE simulations that were used to investigate the performance of the developed subroutine are described.


Polyamide Viscoplasticity Material parameters Finite element method UMAT 


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Copyright information

© Chinese Chemical Society, Institute of Chemistry, Chinese Academy of Sciences and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Fundamental Technical Sciences DivisionWarsaw University of Life SciencesWarsawPoland
  2. 2.Faculty of Materials Science and EngineeringWarsaw University of TechnologyWarsawPoland

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