Long-Term Effects Of Moisture Absorption In CF/PEKK Composites

Abstract

Carbon fiber-reinforced polyetherketoneketone (CF/PEKK) thermoplastic composites were tested under various aging conditions to investigate the effects of moisture absorption on their mechanical properties, including static and fatigue performance. Accelerated moisture uptake was modeled up to saturation using Fick's law, enabling the derivation of the corresponding moisture absorption curve. This experimental procedure replicates the long-term environmental exposure typically experienced by high-performance composites. Both unconditioned (as-received) and moisture-conditioned CF/PEKK samples were analyzed to assess changes in static and fatigue responses under cyclic loading. The results demonstrated a reduction in overall mechanical performance for the conditioned samples compared to their unconditioned counterparts, indicating the detrimental impact of moisture on fatigue life and structural integrity.