Avaliação da resistência à tração de materiais compósitos reforçados com fibras contínuas de Curauá

Abstract

In the present work were produced specimens of epoxy resin composite materials reinforced with cureuá fibers continuously arranged in the matrix. The composites were manufactured by manual molding, compression molding in a mold developed so that the specimens meet the dimensions of standard ASTM D638-14 type 1, and were also made at room temperature (T = 23ºC). To evaluate the behavior of the composite in tensile tests, three variables with potential influence on such mechanical characteristics were sought: fiber mass percentage, volumetric percentage of sodium hydroxide in aqueous solution, while the reinforcement material is subjected to alkaline treatment. Two levels were used for fiber percentage (5% or 15%), four levels for volumetric NaOH percentage (2.5%, 5%, 7.5% or 10%) and three levels for exposure time. (2.5h, 5h or 10h). Five extra specimens were also produced for comparison purposes, they did not undergo any type of chemical treatment and have fiber percentage of: 0%, 5%, 10%, 15% and 20%. The controllable factor with the greatest influence on the tensile test results was the fiber percentage, in general the group with 15% fiber percentage obtained an average rupture stress of 88.94 MPa against 52.39MPa the group with percentage of fiber. 5% fiber, representing a 69.76% improvement with the addition of a 10% increase in fiber mass percentage. In addition, the influence of the three factors on the Elasticity Module and the maximum elongation using Minitab was analyzed.