Application of Integral-Type Deformation Pickups for Evaluating the Fatigue Damage of Carbon Composites

Cyclic tests of specimens of a carbon-fiber-based composite material were performed and their operation time was evaluated using an integral-type deformation pickup (ITDP). The pickup includes a polished aluminum foil (sensitive element), which is pasted on the surface of a specimen and deformed together with it. Its images were recorded with an M(sic)C-9 microscope additionally equipped with a digital camera. To analyze the deformation relief using ITDPs, a complex of informative parameters was calculated and the character and typical stages of their changes were discussed and interpreted. It was proposed to use this data when developing built-in sensors for monitoring the state of parts of critical equipment.