Abstract Thermoplastics are used in many industries with many applications and can be manufactured using different processing techniques. Multiaxial loading and non-proportionality between different loading sources are inevitable in many design applications with such materials. In this study, multiaxial fatigue behavior of extruded high density polyethylene (HDPE), polypropylene (PP), and neat polyamide66 (PA66) as well as reinforced with short glass fibers (PA66-G30) was investigated. The effects of mean stress and stress concentration on multiaxial fatigue behavior were also studied. Analytical models to account for these effects based on observed damage mechanism are presented and discussed by the comparing with the experimental data.

中文翻译：

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热塑性塑料的多轴疲劳行为，包括平均应力和缺口效应：实验和建模

摘要 热塑性塑料用于许多行业，用途广泛，可以使用不同的加工技术进行制造。在使用此类材料的许多设计应用中，多轴载荷和不同载荷源之间的非比例性是不可避免的。在这项研究中，研究了挤压高密度聚乙烯 (HDPE)、聚丙烯 (PP) 和纯聚酰胺 66 (PA66) 以及短玻璃纤维增​​强材料 (PA66-G30) 的多轴疲劳行为。还研究了平均应力和应力集中对多轴疲劳行为的影响。通过与实验数据的比较，提出并讨论了基于观察到的损伤机制来解释这些影响的分析模型。