Analisa Kelesuan Komposit Hibrid daripada Komposit Serat Kenaf/Kevlar yang Diperkukuhkan dengan Epoksi

Abstract

This study is aimed to investigate the fatigue limit of the hybrid composites of kenaf and kevlar reinforced epoxy. Most of the engineering components used in the military appliance and in high technology competition like Formula One Racing car, uses synthetic fibre as their main component in their structural design due to their high mechanical properties. However, by using this material in a small portion of quantity is extremely expensive, uneconomical and becomes over-designed. In this study, kevlar-29 and a woven kenaf being hybrid together using technique of vacuum resin infusion. The fatigue test was conducted at a constant stress amplitude with frequency of 3 Hz, in accordance to ASTM D3479. It was found that the transition region has significant influence on the fatigue results since there are significant reductions on Young’s Modulus. In addition, the endurance limit for the developed composites was almost similar with the Aluminium Alloy with known knee of shape determining the exact fatigue limit. The fatigue limit was read at a million cycles (1005498 cycles). The SEM study has showed the damage mechanism of this developed composites which is started by matrix cracking and followed by fibre breakage and delamination between kenaf fibre and kevlar fibre once the develop composite reach the failure point. Thus, this development of hybrid composite shows good agreement findings and has high potential to replace or reduce the usage of synthetics fibre.