Abstract The investigation of the carbon fibre reinforced plastic components under vibration fatigue testing is known to be challenging; as it involves the analyses of both the mechanical response and the inherent self-heating behaviour which emerges due to the high-frequency testing. The paper will firstly address an open question about the so-called critical event, which is a sudden change in one of the dynamic parameters measured during the fatigue test. Past experiments showed that such a change is associated with delamination, but its onset and early growth were not clarified. Therefore, a set of interrupted fatigue tests and CT scan measurements will show the onset of delaminations and how these are correlated with the vibration parameters. The second objective is to investigate the failure behaviour under vibration fatigue and elevated environmental temperatures. The research will present both the experimental set-up for achieving fatigue under environmental conditions and the vibration data obtained from testing samples at many severity levels; both in terms of applied mechanical vibrations and thermal loads. The paper will investigate how the inherent self-heating behaviour and the applied thermal load will affect the time to failure of composites. The relationship between fatigue behaviour and environmental temperature conditions are presented in two forms. The first one is a typical S-N curve, whereas the second one, the relationship between the response phase and hot-spot temperature data. Both relationships will show how relevant is the environmental temperature in terms of fatigue behaviour for the type of components presented in this paper.

中文翻译：

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CFRP复合材料在振动和热载荷下的实验疲劳行为

摘要 众所周知，在振动疲劳试验中对碳纤维增强塑料部件的研究具有挑战性。因为它涉及对机械响应和由于高频测试而出现的固有自热行为的分析。本文将首先解决一个关于所谓临界事件的悬而未决的问题，即疲劳测试期间测量的动态参数之一的突然变化。过去的实验表明，这种变化与分层有关，但其发生和早期生长尚未阐明。因此，一组间断的疲劳测试和 CT 扫描测量将显示分层的开始以及这些与振动参数的相关性。第二个目标是研究振动疲劳和升高的环境温度下的失效行为。该研究将展示在环境条件下实现疲劳的实验装置以及从多个严重级别的测试样品中获得的振动数据；在施加的机械振动和热负荷方面。本文将研究固有的自热行为和施加的热负荷将如何影响复合材料的失效时间。疲劳行为与环境温度条件之间的关系以两种形式呈现。第一个是典型的SN曲线，而第二个是响应相位与热点温度数据之间的关系。