Thermo-mechanical behavior of polyethylene under mechanical loads at cryogenic and elevated temperatures

For the design of a polymer liner in a high-pressure vessel, experimental and numerical analyses of high density polyethylene (HDPE) are conducted under tensile and compressive loads. The effect of temperature on the mechanical behavior of the HDPE is investigated experimentally in a range of 223K to 373K. For tensile and compression tests, specimens are cut out of a prototype polymer liner, which is to be developed for automobile high-pressure hydrogen tanks. The specimens include manufacturing influences of the future used liner. Investigating the effect of temperature numerically in a finite element analysis, two different material models are taken into consideration to represent the thermo-mechanical behavior of the HDPE: an elastic-plastic material model with isotropic hardening and a hyperelastic material model. The results of the finite element analyses are compared with the experimental results in the entire temperature range. Temperature-dependent impacts of the tension-compression asymmetry are quantified experimentally and numerically for the mechanical behavior of polyethylene. (C) 2016 Elsevier Ltd. All rights reserved.