In recent years, material scientists have been focusing on the utilization of materials from natural resources due to environmental concerns. In the same context, the aim of this work is to evaluate impact response, sound absorption behavior, and vibration damping characteristics of natural-based composite sandwich made of flax as skin reinforcement and agglomerated cork as core. Vacuum bagging method was used for manufacturing composite sandwiches with different cork densities of 240, 280, and 340 kg/m3. Composite sandwiches have also been manufactured by using glass as skin reinforcement for comparison. Low velocity impact test was conducted and found that glass fiber reinforced composite sandwich required 73–77% more energy to perforate when compared to the flax fiber reinforced composite sandwich irrespective of core density. Flax fiber reinforced composite sandwich has 45–96% higher sound absorption capacity and 27–32% higher vibration damping ratio than glass fiber reinforced composite sandwich irrespective of core density. This is due to multiscale structure and cellular nature of the flax fiber and the cork materials, respectively. These enhancements in sound and vibration are accomplished with just little forfeits in perforation energy. This study recommends that, if optimized, the natural-based composite sandwich could be an ecologically appealing answer for automobile and construction applications, where impact behavior is important, along with sound and vibration properties.

中文翻译：

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由亚麻和软木软木制成的天然复合夹层的冲击、声音和振动响应的实验研究

近年来，由于环境问题，材料科学家一直专注于利用来自自然资源的材料。在相同的背景下，这项工作的目的是评估以亚麻作为表皮增强材料和以软木为核心的天然复合夹层的冲击响应、吸声行为和减振特性。真空袋装法用于制造不同软木密度为 240、280 和 340 kg/m3 的复合夹层。为了比较，还使用玻璃作为表皮增强材料制造复合三明治。进行了低速冲击试验，发现与亚麻纤维增强复合材料夹层相比，无论芯密度如何，玻璃纤维增​​强复合材料夹层都需要多 73-77% 的能量来穿孔。无论芯密度如何，亚麻纤维增强复合夹层的吸声能力比玻璃纤维增​​强复合夹层高 45-96%，减振率高 27-32%。这是由于亚麻纤维和软木材料的多尺度结构和蜂窝性质。这些声音和振动的增强是在几乎没有穿孔能量的情况下实现的。这项研究建议，如果优化，天然复合夹层可以成为汽车和建筑应用的生态吸引力答案，在这些应用中，冲击行为以及声音和振动特性很重要。这是由于亚麻纤维和软木材料的多尺度结构和蜂窝性质。这些声音和振动的增强是在几乎没有穿孔能量的情况下实现的。这项研究建议，如果优化，天然复合夹层可以成为汽车和建筑应用的生态吸引力答案，在这些应用中，冲击行为以及声音和振动特性很重要。这是由于亚麻纤维和软木材料的多尺度结构和蜂窝性质。这些声音和振动的增强是在几乎没有穿孔能量的情况下实现的。这项研究建议，如果优化，天然复合夹层可以成为汽车和建筑应用的生态吸引力答案，在这些应用中，冲击行为以及声音和振动特性很重要。