Development of a lifetime prediction concept of continuous fibre-reinforced plastics based on time-temperature-superposition by using NIR-spectroscopy.

使用近红外光谱法开发基于时间-温度叠加的连续纤维增强塑料的寿命预测概念。

• 批准号: 469043941
• 负责人: Dr.-Ing. Wilfried Liebig
• 金额: --
• 依托单位: Institut für Angewandte Materialien - Werkstoffkunde (IAM-WK)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/469043941?language=en
• 关键词: Development; lifetime; prediction; concept; continuous

Fibre-reinforced plastics show a time and temperature dependent material behaviour. These dependencies are related since both arise from molecular motions and rearrangements. This correlation is known as time-temperature superposition and is mainly used in dynamic-mechanical analyses to determine mechanical properties of (fibre-reinforced) plastics in a wide time and temperature range while reducing the experimental effort. The aim of the proposed research project is to apply the time-temperature superpostion in the context of fatigue experiments. A testing methodology will be developed with the aim to predict the temperature and frequency dependent fatigue lifetime of continuously fibre-reinforced plastics as well as stiffness degradation curves. Experimental inverstigations on coupon level will be carried out on pure resin specimens as well as laminates built from multiple glass fibre-reinforced plies with varying orientations. The influence of internal heating owing to dissipation effect on the materials degradation behaviour is examined indepenantly from a purely mechanical load. The methodology is validated by means of suitable long-term experiments and the limitations of the concept are discussed. Near-infrared (NIR) spectroscopy measurements are carried out in the course of the experiments to determine the specimes absorption spectra. These spectra show a correlation with the mechanical and thermal loading history since different kinds of loads give rise to different molecular motions and molecular rearrangements. The NIR spectra can thus serve as a measure for the degradation of (fibre-reinforced) plastics. The quantitative relations between mechanical and/or thermal loads as well as the NIR spectra will be investigated in detail in the course of the proposed research project. A concluding result of the project will be the determination of the remaining service life of a fibre-reinforced plastic by means of NIR measurements without knowing the materials loading history. NIR spectroscopy shall thus be established as a method for fatigue lifetime prediction thereby eliminating or reducing the need for expensive stiffness and crack density measurements.

纤维增强塑料表现出时间和温度相关的材料行为。这些依赖性是相关的，因为两者都来自分子运动和重排。这种相关性被称为时间-温度叠加，主要用于动态力学分析，以确定（纤维增强）塑料在宽时间和温度范围内的机械性能，同时减少实验工作量。拟议的研究项目的目的是在疲劳实验的背景下应用时间-温度叠加。将开发一种测试方法，目的是预测连续纤维增强塑料的温度和频率相关的疲劳寿命以及刚度退化曲线。将对纯树脂试件以及由具有不同取向的多个玻璃纤维增强层合板构建的层合板进行试样水平的实验研究。由于耗散效应对材料降解行为的内部加热的影响独立于纯机械载荷进行检查。该方法通过合适的长期实验进行了验证，并讨论了该概念的局限性。在实验过程中进行近红外（NIR）光谱测量以确定样品的吸收光谱。这些光谱显示出与机械和热负荷历史的相关性，因为不同种类的负荷引起不同的分子运动和分子重排。因此，近红外光谱可以作为（纤维增强）塑料降解的量度。在拟议的研究项目过程中，将详细研究机械和/或热负荷以及近红外光谱之间的定量关系。该项目的最终结果将是在不知道材料加载历史的情况下，通过近红外测量确定纤维增强塑料的剩余使用寿命。因此，应将NIR光谱法确立为疲劳寿命预测的方法，从而消除或减少对昂贵的刚度和裂纹密度测量的需要。