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.

进行了连续多尺度分析，以研究温度对聚合物材料的机械性能和疲劳行为的影响。随着温度的升高，可以清楚地观察到弹性和塑性特性的非线性退化，这是由聚合物分子的相变引起的。还通过基于能量耗散的塑性有限元分析来评估温度对裂纹扩展速率的影响。通过将巴黎系数表示为温度的函数，构造了巴黎区域裂纹扩展速率的连续曲线。本研究中预测的裂纹扩展速率与聚酰胺66上已发布的实验数据非常吻合。