An experimental study of self-diagnosis of interlaminar damage in carbon-fiber composites

An experimental study was conducted to sense interlaminar delamination in carbon-fiber composites utilizing inherent material piezoresistivity. Mode I and II interlaminar fracture tests were carried out on double cantilever beam and end-notched-flexure specimens following ASTM standards. The traditional DC-sourcing two-point probe technique was employed to measure the through-thickness electrical resistance change. For comparison, optical marker method and acoustic emission technique were also applied to detect interlaminar crack growth. The investigation demonstrates the application potential of the self-sensing capabilities of carbon-fiber composites for structural health monitoring.