Abstract High-density polyethylene exhibits discontinuous slow crack growth (SCG) mode in fatigue and creep conditions. To simulate the unique SCG mode, the crack layer (CL) theory can be adopted as an alternative method. However, the stochastic approach is also required for reliability-related problems. In this study, the current deterministic CL model was modified to describe the stochastic discontinuous SCG. First, the influence of the normally distributed nine input parameters in CL simulation on discontinuous SCG kinetics and the resulting lifetime distributions were thoroughly investigated. Second, important CL parameters that affect discontinuous SCG kinetics and the final lifetimes were identified. Then, the 2- and 3-parameter Weibull function and the Birnbaum–Saunders (B–S) function were compared to determine the function that correctly fits the lifetime distribution from discontinuous SCG. Finally, appropriate equations of the scale and shape parameters of the B–S function were developed with regard to the identified parameters.

中文翻译：

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使用裂纹层理论随机研究材料和物理参数对 HDPE 缓慢裂纹扩展行为的影响

摘要 高密度聚乙烯在疲劳和蠕变条件下表现出不连续的缓慢裂纹扩展 (SCG) 模式。为了模拟独特的 SCG 模式，可以采用裂纹层 (CL) 理论作为替代方法。然而，与可靠性相关的问题也需要随机方法。在本研究中，修改了当前的确定性 CL 模型来描述随机不连续 SCG。首先，深入研究了 CL 模拟中正态分布的九个输入参数对不连续 SCG 动力学和由此产生的寿命分布的影响。其次，确定了影响不连续 SCG 动力学和最终寿命的重要 CL 参数。然后，比较了 2 和 3 参数 Weibull 函数和 Birnbaum-Saunders (B-S) 函数，以确定正确拟合不连续 SCG 寿命分布的函数。最后，根据确定的参数开发了 B-S 函数的尺度和形状参数的适当方程。