Experimental Modal Analysis [EMA] on Random Oriented Pressed Mat Fibre/Epoxy Composites

Abstract

High increase in consumption of coconut fruit for food processing and other industrial usage nowadays lead to increase in the production of coconut trash in the form of coir fibre. These coir fibres mostly disposed as unwanted waste since there are not much further applications to utilize the coir fibres. Furthermore, the aerospace industries currently are looking for more to optimize the performance of the existing materials (e.g. metal and synthetic fibre composite) that would be introduced in aircraft structure which relatively cut the cost in production, maintenance, and in-service aircraft, eco-friendly, and low in weight factor. Therefore, natural fibre reinforce composite might be recommended answers to solve these existing problems whereby this solution already been introduced in the automotive and civil application. The existing raw coir fibers used are in the form of pressed mat and originally in the random oreineted fiber form. They have been used directly in the compression moulding process together with different weight ratio of 25% fiber loading with epoxy resins under room temperature and controlled pressure for composite fabrication process. The fibers underwent no modification at all. Then, Experimental Modal Analysis [EMA] will be used to determine and establish preliminary data of dynamic characteristics such as natural frequency, damping ratio, and mode shape of coir fibre/epoxy composites. Five aspect ratios of coir fibre composite panel were tested and the results shown that dynamic characteristics of the coconut coir fibre reinforced composite are dependent on the dimension of fibre. These properties data will be recorded and might be used as a reference for further strcutures design analysis such as aeroelastic and vibration analysis