Electro-Fracture Studies Of Natural Fiber Composites

The electro-fracture studies on jute/epoxy composites are conducted for monitoring damage under mode-I interlaminar fracture loading condition. A well-connected electrical network is built inside the composites by electro-flocking microcarbon fibers between the laminates and dispersing carbon nanotubes in the matrix. The effect of carbon fiber length and density on the electro-fracture behavior is studied. The change in electrical resistance is measured using a novel four-probe method through the thickness direction of cantilever beam test specimen. Results show that the maximum increase of fracture initiation toughness is 75% by the composite with carbon fibers length of 350 mu m and fiber density of 2000 fibers/mm(2) compare to composites with no carbon fibers. For all composite types, the increase in resistance is not noticeable before crack initiation. The cycles of fracture energy build up and release during the crack propagation are accurately detected onsite by the composite with carbon fiber length of 350 mu m and fiber density of 2000 fibers/mm(2).