Multiscale study for the temperature effect on the mechanical properties and fatigue crack growth rate of polyamide 66

Sequential multiscale analysis was performed to investigate the effect of temperature on the mechanical properties and fatigue behaviors of a polymeric material. With increasing temperature, a nonlinear degradation of the elastic and plastic properties were clearly observed, which arose from the phase transition of polymer molecules. The influence of the temperature on the acceleration of crack growth rate was also evaluated via the plastically dissipated energy-based finite element analysis. Continuous curves of the Paris-regime crack growth rate were constructed by representing the Paris coefficients as a function of temperature. The predicted crack growth rates in the present study match well with the published experimental data on polyamide 66. The proposed framework provides an accurate estimation of the mechanical properties and fatigue crack growth rate of polymers, with a reduced reliance on experiments. (C) 2020 Elsevier Ltd. All rights reserved.