Open Hole Tensile Properties of Kenaf Composite and Kenaf/Fibreglass Hybrid Composite Laminates

Abstract

Drilling induced in fibre reinforced polymer resulted in high rate of parts rejection and thus affects the in-service performance of the composite product. Therefore, the tensile testing of hybrid composite with drilled holes is necessary to render them satisfaction in industrial application. The objective of the present research is to develop long kenaf composites and long kenaf/woven glass reinforced polyester resin composites. The tensile properties of those composites with drilled holes were investigated. The measurements were taken from the residual tensile strength of impacted specimens and the open hole specimens. From there, the damage area of the composites could be predicted. It is found that the long kenaf composite was more notch sensitive than long kenaf/woven glass hybrid composite. The hybrid composite was stronger than long kenaf composite. However, the damage progression mechanisms in the two materials were similar. Failure for both kenaf composite and long kenaf/woven glass hybrid composite started around the hole. The polymer matrix failed initially followed by fibre–matrix debonding.