On the Effective Tensile and Bending Properties of Plain Weave Single-Ply E-Glass/Epoxy

Abstract

This study empirically, numerically, and analytically analyzes the tensile and bending behavior of a plain weave single-ply E-glass/epoxy composite. In the empirical part of the study, tensile and simple bending experiments are conducted. Finite element method is used in the modeling part of the numerical study. Transverse and longitudinal fibers of the plain woven composite are modeled in one and three dimensions by using the Abaqus software. Finally, mixture ratio approach and composite beam approach are considered in the analytical part of the study. Elastic modulus, Poisson’s ratio, and critical bending radius are obtained experimentally, and are compared to the results of the finite element analyses and the results of the analytical study where applicable. The results closest to the empirically obtained ones are obtained by three-dimensional finite elements analysis. Moreover, the mechanical characteristics obtained by the composite beam approach used in the analytical study are also very close to the values obtained by three-dimensional finite elements analysis. I. Introduction Woven composites of symmetric and balanced material with a few layers are frequently used in aerospace structures. Determining the material characteristics of these structures is of critical importance for safe and functional designs. Polymer$matrix woven composites are very lighter than traditional materials and they have high levels of impact resistance and performance. Carbon fiber composites are used in aviation and space industries due to their high strength and stiffness characteristics. Relative prices of them are higher than other fiber types; hence, they are used in other industries where high performance is required, for example in Formula 1 racing cars or in speedboats. The cost of glass fiber composites is the cheapest with respect to kevlar and carbon; therefore they have the widest area of application, i.e. they are used in maritime and automotive industries and in other industrial areas. Kevlar is more expensive than glass but cheaper than carbon. Especially, their impact resistance is good; they are used in some space structures and in applications such as ballistic bulletproof vests and helmets. In a plain woven composite, fibers form the fabric by consecutively passing over and under each other. Hence, the material is not homogenous along the thickness in any section. In order to analytically determine homogenized material characteristics of woven composites, several micromechanical models have been developed so far. According to the experiments on carbon fiber and polymer$matrix woven composites 1