ANÁLISE DO GRADIENTE DE TENSÃO NA BORDA DE UM FURO EM LÂMINA DE TECIDO HÍBRIDO DE FIBRA DE VIDRO/CARBONO

Abstract

The technological and economic growth of modern society, and the constant search for new products that cater higher demands of industry and society, have allowed further developments on researchs for new materials. Thus the research area that seeks the integration of material in order to create a single compound with specific properties for the application gained his own space: the composite. The hybrid lamina composite combine two or more types of fiber on the same fabric, seeking for higher performances for the application. However, due to recently creation of this types of materials the knowledge for mechanical performance in some situations are scarce. Hence we saw the opportunity to analyze the stress behavior at the edge of a stress concentrator in a laminate composite reinforced with hybrid fabric of carbon fiber / glass. In order to verify if the tensile behavior follows the theoretical gradient for orthotropic materials, the laminate was manufactured using the vinyl ester epoxy resin MOMENTUM 411-350 from DERAKANE®®. With the purpose of performing a more comprehensive analysis of the behavior of the composite, samples were made varying fiber orientation, with reference to carbon fiber in relation to the loading. Thus, the CP0, CP30, CP45 and CP60 samples, with dimensions according to ASTM D 5766-02, were manufactured and subjected to uniaxial tensile testing following ASTM D3039M- (2014). Tension data were obtained during the test using strain-gauges and it was possible to create comparative graphs between the analytical stress curve according to the distance from the hole edge. The final results were satisfactory to prove that the lamina with hybrid fabric of fiberglass / carbon presents orthotropic performance, and in the periphery of the hole presents the expected dispersion for materials with this property.