Effect of Testing Temperature on the Energy Absorption Behavior of Carbon Fiber/PEEK Composite Tubes

The primary objective was to study the effect of testing temperature on the energy absorption characteristics of carbon/PEEK composite tubes. Composite tubes with 0° fiber architecture were tested at different temperatures in the range from -100°C to 150°C. Tubes tested at -100°C and -80°C failed catastrophically by longitudinal cracking parallel to fibers and splitting of tube wall into segments. This was attributed to the reduced fracture toughness at these low temperatures. Composite tubes tested at temperatures above -60°C crushed progressively by the splaying mode. The energy absorption capability increased with increasing temperature from -60°C to -10°C and then decreased with further increase of temperature. A maximum energy absorption capability of 245 kJ/kg was displayed by the tubes tested at -10°C. This variation of energy absorption was attributed to the changes in morphological features of the crush zone and the mechanical properties of composite material with temperature.