ABSTRACT

Design and development of new biomaterials has become a necessity due to adverse effects of chemical materials on people and nature. As the mechanical properties of biomaterials are not as good as those of chemical materials, their different configurations should be developed and tested before considering them for practical applications. Acoustic and mechanical properties of homogenous and hybrid jute and luffa biocomposites are investigated here. Homogenous and hybrid composites using jute and luffa fibers and epoxy are designed and manufactured and methods for identification of the acoustic and mechanical properties are summarized. Acoustic and structural frequency response functions are measured using homogenous and hybrid composite plates to determine their natural frequencies and loss factors. Using the experimental modal parameters of the plates and their theoretical models, elasticity moduli of biomaterials are determined. The acoustic absorption properties and transmission losses of homogeneous and hybrid composites are determined using impedance tube method. Results show that homogenous and hybrid jute and luffa composites can have moderate absorption coefficients (0.1 for a thickness of 4 mm) and superior damping performance of luffa and stiffness property of jute can be used together to produce hybrid composites with high damping (2.2–2.6%) and elasticity modulus (3–5 GPa).

摘要

由于化学材料对人和自然的不利影响，设计和开发新的生物材料已成为必然。由于生物材料的机械性能不如化学材料，因此在考虑将它们用于实际应用之前，应开发和测试它们的不同配置。这里研究了同质和混合黄麻和丝瓜生物复合材料的声学和机械性能。设计和制造了使用黄麻和丝瓜纤维和环氧树脂的均质和混合复合材料，并总结了声学和机械性能的识别方法。使用同质和混合复合板测量声学和结构频率响应函数，以确定它们的固有频率和损耗因子。利用板的实验模态参数及其理论模型，确定了生物材料的弹性模量。采用阻抗管法测定均质和混合复合材料的吸声性能和传输损耗。结果表明，均质和混合的黄麻和丝瓜复合材料具有中等的吸收系数（4 mm 厚度时为 0.1），丝瓜的优异阻尼性能和黄麻的刚度特性可以共同用于生产具有高阻尼的混合复合材料（2.2-2.6 %）和弹性模量（3-5 GPa）。