Abstract The aim of this work is to evaluate the dynamic properties of nonwoven flax, hemp, kenaf and glass fibre-reinforced polypropylene (PP) composites. Also, the influence of some parameters, such as the type of reinforcement, the fibre/matrix weight ratio, the fibre orientation and the porosity content, on the damping behaviour of these nonwoven composites is investigated. To this end, a free flexural vibrations analysis was conducted to experimentally identify their natural frequencies and their associated loss factors. The obtained results show that the nonwoven composites reinforced by natural fibres present higher loss factors compared with those of the glass-PP composite. These interesting damping properties make these nonwoven composites very attractive for automotive applications where the dissipation of vibrations is highly requested.

中文翻译：

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用于汽车内饰件的非织造天然纤维增强聚丙烯复合材料的阻尼分析

摘要 这项工作的目的是评估非织造亚麻、大麻、洋麻和玻璃纤维增​​强聚丙烯 (PP) 复合材料的动态性能。此外，还研究了一些参数对这些非织造复合材料的阻尼行为的影响，例如增强材料的类型、纤维/基体重量比、纤维取向和孔隙率。为此，进行了自由弯曲振动分析，以通过实验确定它们的自然频率及其相关的损耗因子。所得结果表明，与玻璃-PP 复合材料相比，天然纤维增强的非织造复合材料具有更高的损耗因子。这些有趣的阻尼特性使这些非织造复合材料对于高度要求消散振动的汽车应用非常有吸引力。