Application of Acousto-Ultrasonics for Predicting Hygrothermal Degradation of Unidirectional Glass-Fiber Composites
Unidirectional composites made of glass fibers of two different glass compositions, ‘E’ and ‘N’, were exposed to water at different temperatures, and the degradation process was monitored with the acousto-ultrasonic technique. The study shows that the rate of degradation is dependent on glass composition, but the degradation mechanism is independent of glass composition. The strength data of two composites exposed to boiling water for different lengths of time correlated with the normalized stress wave factor. The strength predictions made at temperatures of 60°C and 80°C, based on this correlation, show close agreement with the experimentally measured values.
KeywordsAcoustic Emission Aging Time Flexural Strength Stress Wave Glass Composition
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