Abstract In this study, slow crack growth (SCG) resistances of defective and normal high density polyethylene (HDPE) pipes were measured using the stiff-constant K (SCK) specimen, where the stress intensity factor (SIF) was maintained at a constant value within a certain crack length range. A significantly reduced SCG resistance was observed in the defective pipe; a detailed procedure for evaluating SCG kinetics using the SCK specimen has been provided herein. The results of a fracture surface analysis indicate that the white window patterns, resulting from poor carbon black dispersion, are the main reason for poor SCG performance. In addition, a crack layer (CL) model was derived for the SCK specimen geometry and was compared with experimental results. It was observed that the crack and process zone growth resistance parameters were significantly lower in the case of the defected pipe than those in the case of the normal pipe.

中文翻译：

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使用刚度常数 K 试样表征和建模有缺陷的高密度聚乙烯管的缓慢裂纹扩展行为

摘要 在这项研究中，使用刚度常数 K (SCK) 试样测量了缺陷和正常高密度聚乙烯 (HDPE) 管道的慢裂纹扩展 (SCG) 阻力，其中应力强度因子 (SIF) 保持恒定值在一定的裂纹长度范围内。在有缺陷的管道中观察到显着降低的 SCG 电阻；此处提供了使用 SCK 样本评估 SCG 动力学的详细程序。断口分析结果表明，由炭黑分散性差导致的白色窗口图案是 SCG 性能差的主要原因。此外，还推导出了 SCK 试样几何形状的裂纹层 (CL) 模型，并与实验结果进行了比较。