Mechanical characterization of quasi-isotropic intra-ply woven carbon-Kevlar/epoxy hybrid composite

Abstract

The aim of this study was to find the mechanical characteristics of quasi-isotropic intra-ply woven Carbon-Kevlar/Epoxy hybrid composite by experimental investigation. The composite laminate configuration of quasi-isotropic, symmetric, balanced and intra-ply hybridization was selected in accordance with applications requiring thin and isotropic material properties. The composite laminate was fabricated using hand-layup and vacuum-bagging techniques and ASTM International (formerly known as American Society for Testing and Materials) standards were followed for all the tests. The tests conducted in this study include Void-content and density test, Tensile test, Flexural test, Izod impact test, Inter-laminar shear (ILSS) test and Scanning Electron Microscopy (SEM) test. The void test was conducted to ensure the fabrication quality of the composite laminate. Different mechanical tests were conducted to find its properties under different loading conditions and SEM was used to understand the failure modes involved in the fracture of a tensile specimen. The material showed moderate and balanced mechanical properties such as good bending and impact behavior that can be used in applications that require isotropic properties with both bending and impact strengths. The tensile, flexural, impact and inter-laminar shear strengths of the material determined by experimental investigation are 270 MPa, 196.6 MPa, 1440.4 J/m and 17.4 MPa respectively. SEM analysis revealed that matrix cracks, fiber pull out, fiber–matrix debonding, fiber breakage and delamination were the major failure modes in the fracture of the tensile test specimen.