Strength Characteristics of Carbon Fiber Reinforced Plastic in Shear and Cyclic Extension-Compression after 7 Years of Climate Exposure

Abstract

The results of studies of carbon fiber reinforced plastic (CFRP) for aviation purposes based on the Cycom 977-2 epoxy binder and Tenax® IMS carbon fibers after 7 years of exposure under a canopy and on an open atmospheric stand in the warm humid climate of Sochi are presented. The influence of climatic aging is determined by the change in strength parameters during interlaminar shear and cyclic tension – compression. After exposure under a canopy, the strength characteristics during interlaminar shear and cyclic tension–compression increase by 7–13 %. If the plate is under the direct influence of solar radiation, then the strength characteristics of the material are slightly reduced, but remain at the level of the original values. The kinetic concept of fracture was used to interpret the results. The thermal activation analysis showed that the characteristics of the inelasticity of the plate specimens, both in terms of the relaxation and hysteresis parts of energy absorption, correspond to their strength characteristics.