Mechanical Characterization and Vibration Analysis of Hybrid E-glass/Bagasse Fiber Polyester Composites

Abstract

This study is concerned with the mechanical properties like tensile strength, flexural strength, density, hardness and vibration properties of the hybrid sandwich type composite plates made from E-glass/bagasse and unsaturated polyester resin GP-7150 experimentally as well as using finite element analysis Hybrid composite plates were prepared by hand lay-up method with 3%, 6%, 9%, 12%, and 15% weight of bagasse natural fiber. Alkaline treatment of bagasse fiber was done by dipping it in 5% aqueous NaOH solution for 72hours. This results in the removal of a certain amount of wax, lignin, and oils covering the exterior of fiber cell wall which ultimately increases surface roughness resulting into better bonding between fiber and resin. Chemically treated bagasse fibers were then mixed with E-glass fibers in the unsaturated polyester matrix. Samples were prepared by keeping variable bagasse fiber and polyester resin content with constant E-glass fiber content. It was observed that increase in bagasse fiber content was accompanied by the improvement in mechanical properties with 9% bagasse fiber plate showing the best set of properties. Vibrational analysis of hybrid composite plates reveals that highest natural frequency of vibration was found for 9% bagasse fiber plate resulting into best vibrational properties. The decrease in mechanical properties beyond 9% of fiber content can be accounted for the insufficient amount of resin. Also, it has been observed that addition of fiber leads to decrease in density of composite plate due to the inherent low density of bagasse fiber than the polyester matrix. To make lightweight and cost effective hybrid composite material which can be used in lightweight structural applications is the main objective of this study.