Nondestructive Evaluation and Characterization of Microfibers Modified Textile Carbon-Phenolic and Carbon-Carbon Composites

Short carbon microfibers have been added to carbon-phenolic fabric composites of plain, eight-harness satin (8HS) and stretch broken 8HS weave architectures. The resulting composites have been studied for their interlaminar mechanical properties as well as process related material evolution mechanisms that result in carbon-carbon (C-C) composites. Dry coupling ultrasonic A-scan velocity measurements, immersion type ultrasonic C-scan technique, acousto-ultrasonic (AU) stress wave factor measurements and vibration damping ratio based nondestructive evaluation-characterization (NDE-C) test parameters were studied in relation to the carbon-phenolic and C-C composites. Interlaminar shear strength (ILSS) tests were conducted along with acoustic emission (AE) monitoring. From the various NDE techniques accompanied by mechanical tests and processing stages, the dependence of fabric weave architectures with short microfibers has been established.