Efeitos da anisotropia e descontinuidades geométricas em PRFV

Abstract

Glass Fiber-Reinforced Polymer composites (GFRP) have been increasingly utilized in the various engineering sectors, for instance: lightweight structures, of automotive, nautical and aerospace industries, among many other applications. As these materials are being applied in engineering projects, it becomes essential to know about its mechanical behavior under the various conditions of loading and service. A problem occurs when the joining of mechanical parts demands the usage of rivets, bolts, pins, etc. These elements, by their own nature, demand the presence of holes, tears and notches, in other words, geometric discontinuities, which create local stresses that compromise the structural performance. The purpose of this dissertation is to study the mechanical behavior and fracture characteristics of a laminated polymer composite consisting of four layers of a balanced bidirectional Eglass fiber fabric as reinforcement, impregnated with a thermoset ortho-terephthalic polyester resin under a uniaxial tensile loading. In the laminated composite developed, the influence of geometric discontinuities is studied through the presence of two different types of circular central milled holes: with and without scarfing. Comparative studies were made about the property of anisotropy and the mechanical and residual properties for two different fiber orientations relative to the loading: 0º/90º and ± 45º, as well as a macroscopic analysis of the fracture. Volumetric density and calcination tests were done in order to characterize the composite.