Caracterização das propriedades mecânicas, elétricas e efeito piezoresistivo para CFRP em matriz epóxi

Abstract

The research investigates the mechanical and electrical properties, as well as the piezoresistive effect, of carbon fiber reinforced polymer (CFRP) composites with an epoxy matrix, aiming at applications in structural reinforcement and structural health monitoring (SHM). Samples reinforced with carbon fibers of different areal weights (200 g/m², 300 g/m², and 400 g/m²) from two manufacturers (Simpson Strong-Tie® and Clever Solutions) were analyzed. These samples underwent tensile testing for mechanical characterization and electrical measurements using a high-precision multimeter and a Wheatstone bridge circuit. The results showed that the fibers from Simpson Strong-Tie® exhibited superior mechanical properties, with significantly higher elastic modulus and ultimate tensile strength compared to those from Clever Solutions. Furthermore, the material displayed consistent piezoresistive behavior, with an average Gauge Factor of 33.28, indicating high sensitivity for sensing applications. It was concluded that CFRPs are viable for structural reinforcement due to their high strength and low weight. The integration of conductive elements for electrical measurements proved effective, although it introduced points of fragility, suggesting the need for further optimization in sample design.