Accelerated aging effects on carbon fiber/epoxy composites

The influence of operational environments on the long-term durability of structural components fabricated with carbon fiber reinforced composites is an ongoing concern. Exposures to ultraviolet radiation, temperature cycles and moisture are known to degrade the polymeric matrix. In this work, carbon-epoxy composites were subjected to accelerated aging in an aging chamber with controlled conditions of temperature, humidity and UV-radiation. Changes within the material are evaluated by Fourier-Transform Infrared (FTIR) Spectroscopy, Dynamic Mechanical Analysis (DMA), interlaminar shear strength and compressive strength, Scanning Electron Microscopy (SEM), and also in terms of mass variation. Although significant changes in mechanical properties were not observed, the effects of accelerated aging on the composite material were evidenced by mass loss, fiber exposure, chemical alterations, increased crack density in interlaminar shear tests and fiber buckling in fractured specimens after compression testing.