Flexural fatigue performance and electrical resistance response of carbon nanotube-based polymer composites at cryogenic temperatures

• We studied the cryogenic flexural fatigue and electrical resistance responses of CNT-based composites.
• Cooling from room temperature to 77 K causes an increase in the fatigue resistance.
• The composite fatigue performance is affected by the nanotube content.
• The electrical resistance-based sensing method was successfully applied.

We study the flexural failure and electrical resistance change of carbon nanotube (CNT)-based polymer composites under cyclic loading at cryogenic temperatures. Fatigue tests were performed on CNT/polycarbonate composites at room temperature and liquid nitrogen temperature (77 K) using the three-point bending method, and the measurements of the specimen electrical resistance were made during the tests. Also, the specimen fracture surfaces were examined by scanning electron microscopy (SEM) to verify the failure mechanisms of the nanocomposites. The dependence of the mechanical and electrical responses of the nanocomposites on the temperature and the nanotube content was then discussed.