Chopped Areca Nut Fibers as Filler in Epoxy Matrix: Mechanical and Tribological Studies

Abstract

In the current investigation, fibers extracted from the areca nut tree husk were either used unprocessed or processed with an alkaline treatment by being submerged in a 5 % sodium hydroxide solution. The average length of the areca fibers used in this work is 30 mm. Compression molding is used to create the composite out of an epoxy matrix with fibers added at 10, 15, 20 and 25 weight percent. The composites were tested for tensile strength, flexural modulus, Charpy impact, and shore D hardness, all of which showed the significant advantage acquired with quantity of fibers and fiber treatment. Pin on disc tribometer was used to conduct tribological tests on the treated fiber composites to analyse how the fiber-matrix bonding improved with an increase in fiber content. The primary shortcoming of the fibers is their relatively low elongation, which, even after treatment, hardly approaches 4 %. This indicates that the fibers are not uniform in length and prevents direct comparison to comparable composites containing a similar volume and length of natural fibers. The mechanical qualities of materials made with alkali treated chopped areca fibers where found to be enhanced when it was at 20 % volume fraction. A linear increment in values where observed in samples till 20 % volume fraction and a decrement with further increase in volume fraction. In the case of tribological evaluations, lesser values or wears were obtained at combination III for all the 3 loads, 10N, 15N and 20N. HIGHLIGHTS Three different amounts of fibers, namely 10, 15, 20 and 25 wt%, have been introduced in an epoxy matrix, fabricating the composite by compression molding. The composites were subjected to tensile, flexural, Charpy impact and Shore D hardness testing, which all demonstrated the considerable advantage obtained with quantity of fibers and fiber treatment, except in the case of hardness, where limited advantages were encountered. Also wear tests were carried out on treated fiber composites and surface morphology of the worn-out samples was studies, which demonstrated the improvement in fiber-matrix bonding obtained with the growing amounts of fibers. From the results on composites testing, it is evident that the areca nut husk fiber/epoxy polymer composites with an amount of short (30 mm length) random reinforcement introduced of 20 wt%, exhibits the highest peak mechanical properties among all the calculated properties. GRAPHICAL ABSTRACT