Resistência residual após impacto em compósitos híbridos de matriz estér vinílica reforçada por fibra de vidro e Kevlar

Abstract

Throughout the use of a material it is subjected to various types of impact due to the fall of elements of high or low mass and speed. Among the impacts, the low speed is considered the most common request, when considering typical situations of use where these impacts can cause internal damage in the material compromising its integrity. In addition, special attention should be paid to composites that are more susceptible to impact damage than conventional materials. Therefore, the present study aims to make an experimental analysis and model the residual resistance to three-point flexural strength and compression after impact (CAI) of two types of composite laminates of sterile-vinyl polymer matrix, being a reinforced hybrid composite with 11 layers consisting of 8 layers of bidirectional E-Glass and 3 layers of Kevlar 49, and for comparison purposes, another laminate reinforced with 11 layers of bidirectional E-Glass fabric, subject to low-velocity impacts ). Several impact energies (31J, 46J, 61J and 76J) were used in the two laminates until the drilling of the sample. As a result, it was found that the hybrid laminate obtained higher impact strength, while it showed a decrease in both compression and flexion properties at three points after impact, where this loss of integrity in the hybrid can be justified by the occurrence of delamination at the interfaces of the composites.