Comportamento eletro-termomecânico de um compósito ativo de CFRP com fios Ni-Ti embebidos.

Abstract

The possibility of uniting two or more different materials to obtain structures capable to feel and adapt to environment alterations and operational conditions, has been leading to the development of active composites with functional properties that makes possible the control of form, vibration, rigidity and/or structural integrity monitoring. These characteristics are very well accepted in modern technological applications. In this context, active composites were manufactured using pre-impregnated (Pre-Pregs) foils of epoxy with carbon fibers (CFRP) and NiTi shape memory alloy (SMA) thin wires embedded in different conditions, besides copper electrodes for electrical resistance monitoring of the specimens. The NiTi SMA wires, the carbon fibers and the obtained CFRP-NiTi composites were characterized by electrothemomechanical tests of electrical resistance as a function of temperature and deformation, thus verifying the efficiency of embedded electrodes in monitoring the structure when submitted to three points bending cycles. The NiTi wires activation capacity inside the CFRP matrix for buckling and thermal contraction/expansion control was also verified, even though the NiTi wires represent a minimum volumetric fraction in the CFRP-NiTi produced systems.