Electro-bending Behavior of Curved Natural Fiber Laminated Composites

Experiments are performed to understand the electro-bending behavior of conductive jute/epoxy curved composites for monitoring of damage under four-point bending. A well-connected electrical network in the laminated curved composite is obtained by wet flocking micro carbon fibers between laminates and dispersing carbon nanotubes (CNTs) within the matrix. By embedding only 0.1 wt% of CNTs into the composites, the effects of carbon fiber length and density on electro-bending behavior is studied. The normalized curved beam strength (curved beam strength/thickness) of composites marginally increased for a case of carbon fiber length of 350 µm and fiber density of 500 fibers/mm2 compared to composites with no carbon fibers, however for all other cases, it showed slight decrease. The electro-bending behavior of composites of carbon fiber length of 150 µm showed higher percentage resistance change both at crack initiation point as well as at failure of specimen compared to those of carbon fiber length of 350 µm. The longer fiber (350 µm) composites provided rich conductive network and formed new connections to compensate the increase in resistance due to damage growth.