Advanced Materials and Manufacturing (AMM) Research Group, School of Mechanical and Design Engineering, University of Portsmouth, Portsmouth PO1 3DJ, UK.
Molecules. 2020 Jan 9;25(2):278. doi: 10.3390/molecules25020278.
Due to rigorous new environmental legislations, automotive, marine, aerospace, and construction sectors have redirected their focus into using more recyclable, sustainable, and environmentally friendly lightweight materials driven by strengthening resource efficiency drive. In this study, the influence of moisture absorption on flax and flax/glass hybrid laminates is presented with the aim to investigating their low velocity impact behaviour. Three different types of composite laminates namely, flax fibre reinforced vinyl ester, flax fibre hybridised glass fibre and glass fibre reinforced vinyl ester composites were fabricated using resin infusion technique. The moisture immersion tests were undertaken by immersing the different specimens in sea water bath at room temperature and 70 °C at different time durations. The low velocity falling weight impact testing was performed at 25 Joules of incident energy level and impact damage behaviour was evaluated at both ageing conditions using scanning electron microscopy (SEM) and X-ray microcomputed tomography (micro CT). The percentage of moisture uptake was decreased for flax vinyl ester specimens with glass fibre hybridisation. The maximum percentage of weight gain for flax fibre, flax/glass hybrid and glass fibre reinforced composites immersed at room temperature for 696 h is recorded at 3.97%, 1.93%, and 0.431%, respectively. The hybrid composite exhibited higher load and energy when compared flax/vinyl ester composite without hybridisation, indicating the hybrid system as a valid strategy towards achieving improved structural performance of natural fibre composites. The moisture absorption behaviour of these composites at room was observed to follow Fickian behaviour.
由于严格的新环境法规，汽车、海洋、航空航天和建筑等行业已经将注意力转向使用更可回收、可持续和环保的轻量级材料，这是加强资源效率驱动的结果。本研究介绍了吸湿对亚麻和亚麻/玻璃混杂层压板的影响，目的是研究它们的低速冲击行为。使用树脂浸渍技术制造了三种不同类型的复合材料层压板，即亚麻纤维增强乙烯基酯、亚麻纤维与玻璃纤维混杂和玻璃纤维增强乙烯基酯复合材料。将不同的试样分别浸入室温下和 70°C 的海水中进行吸湿试验，不同的时间。在 25 焦耳的入射能量水平下进行低速落体冲击试验，并在两种老化条件下使用扫描电子显微镜 (SEM) 和 X 射线微计算机断层扫描 (micro CT) 评估冲击损伤行为。玻璃纤维混杂化使亚麻乙烯基酯试样的吸湿率降低。在室温下浸泡 696 小时后，亚麻纤维、亚麻/玻璃混杂和玻璃纤维增强复合材料的最大增重百分比分别为 3.97%、1.93%和 0.431%。与未混杂化的亚麻/乙烯基酯复合材料相比，混杂复合材料表现出更高的载荷和能量，表明混杂系统是实现天然纤维复合材料结构性能提高的有效策略。这些复合材料在室温下的吸湿行为被观察到符合菲克定律。
