R. Sheley, J. Tate, M. Tehrani
Texas State University,
United States
Keywords: high temperature thermoplastic composites, tension-tension fatigue, damage mechanism, stress ratio, frequency
Summary:
High-temperature thermoplastic composites (HTTPs), such as carbon fiber-reinforced polyether ether ketone (PEEK) and polyether ketone ketone (PEKK), low modulus poly aryl ether ketone (LM-PAEK), are increasingly utilized in industries like aerospace, marine, automobile, and energy. These materials provide superior mechanical properties, chemical resistance, and thermal stability. Such applications often expose these materials to cyclic loading conditions in extreme environments, leading to potential failure if not properly monitored and maintained. Hence, it is necessary to understand the endurance limit of these materials to ensure their safe and reliable performance. The primary objective of this research is to evaluate composite durability under cyclic loading conditions by tension-tension fatigue and identify key damage causes like matrix cracking, delamination, and fiber-matrix debonding using scanning electron microscopy (SEM). In this research for sample preparation, compression molding and vacuum bagging techniques were used, ensuring consistent material quality. The study concludes that LM-PAEK composites, with careful processing, show promising fatigue resistance, making them suitable for high-performance extreme condition environment applications. These findings provide a framework for optimizing composite design and enhancing material reliability under cyclic loading conditions.