A Study on the Effect of Fiber Parameters on the Mechanical Behavior of Bamboo-Glass Fiber Reinforced Epoxy Based Hybrid Composites

Abstract

Polymeric materials reinforced with synthetic fibers such as glass, carbon, and aramid offer the advantages of higher stiffness and strength to weight ratio as compared to conventional construction materials like wood, concrete, and steel. Despite these advantages, the widespread use of synthetic fiber reinforced polymer composites has a tendency to decline because of their high initial costs and adverse environmental impact. In recent years, the natural fiber composites have attracted substantial importance among the structural materials. There has been a fast growing interest in using the natural fibers as reinforcements in the
composites. The attractive features of natural fibers are their low cost, light weight, high specific modulus, renewability and biodegradability. Among many of
the natural fibers (like jute, sisal, bamboo, coir, banana etc.), bamboo fiber is one of the most promising one, because of its low cost, light -weight, short growth cycle
and high availability. Use of bamboo fiber can help to reduce the demand for wood fibers and environmental impacts associated with wood fiber harvesting, hence considerably lowering the stress on wood forests. Bamboo fiber reinforced
polymer composites have moderate mechanical properties but their properties can be greatly enhanced by mixing of synthetic fibers or by the treatment of fiber in the
alkali medium. Attempts have been made in this research work not only to explore the potential utilization of bamboo fiber but also a means of mixing of other synthetic fiber in the polymer composites for making value added products. Nine
different types of hybrid composites (bamboo and glass fiber) have been prepared by hand lay up technique for physical and mechanical characterizations. The untreated bamboo/glass composites have three different fiber loading
i.e 5:15 wt.% (bamboo: glass fiber loading), 10: 10wt.% (bamboo: glass fiber loading) and 15: 5 wt.% (bamboo: glass fiber loading) by varying the fiber length in each fiber loading from 0.5cm to 1.5cm respectively. The hardness of the three different series of hybrid composites varies from 13.21Hv to 15.95Hv for 0.5cm fiber length, 9.75Hv to 18.51Hv for 1cm fiber length and 19.61Hv to 21.25Hv for 1.5cm respectively. Mechanical properties like tensile strength, tensile modulus, flexural strength and flexural modulus have been measured along with the surface characterizations of the all the fiber reinforced epoxy composites. It has been
observed from this work the tensile strength of the composites slightly increase in all the three different fiber loading irrespective of fiber lengths. The maximum
tensile strength among all the composites is 24.41MPa for 0.5cm fiber length i.e 5wt.% bamboo fiber and 15wt.% glass fiber reinforcement respectively. Whereas, in case of tensile modulus is concerned 1.5cm fiber length shows maximum modulus among all the composites. However, Flexural strength of these composites increases for all the fiber length. Whereas, flexural modulus is concerned the modulli trend slightly varies as compared with flexural strength of
the hybrid composites. Scanning electron microscopy (SEM) has been performed on the samples to study the fracture mechanisms on the composite surface in all the nine different sets of
the samples.