Advanced Materials: TechConnect Briefs 2015Advanced Materials TechConnect Briefs 2015

Informatics, Modeling & Simulation Chapter 2

Model Study for Thermal Deformation and Creep Behavior of Polymers Considering Moisture Diffusion

T.G. An, Y. Lim, N. Kim
Sogang University, Korea

pp. 108 - 111

Keywords: moisture diffusion, ABS (Acrylonitrile-Butadiene-Styrene), two-layer viscoelastic-plastic model, polymer creep behavior, thermal and humidity creep

ABS(Acrylonitrile-Butadiene-Styrene) polymer is viscoelastic materials which are subject to permanent deformation when exposed to certain temperatures and humidity levels for long periods of time. In this paper, this phenomenon was defined as a creep phenomenon of Polymeric materials resulting from temperatures and humidity. To establish a numerical model that can simulate creep behaviors, tensile tests to which temperatures were given and creep tests to which temperatures/humidity/loads were given were conducted. Thereafter, to consider the effect of distributed humidity inside the ABS specimen, diffusivity that can make the simulated creep behavior coincided with reality were derived from the test which is under unbalanced-diffusion condition. In particular, interpolation functions that can predict material constants that show the creep properties of ABS were derived according to temperatures and humidity levels with mechanical properties and diffusivity. Creep tests to which temperatures and humidity changing over time were given were conducted on random specimens and the test results were compared to numerical analysis results. According to the results, the results of calculations using the creep constant prediction interpolation functions and the numerical model established through the present study could well simulate actual creep behavior resulting from temperatures and humidity.