Measuring In-plane Elastic Moduli of Composites with Arrays
نویسندگان
چکیده
Ultrasonic measurements of elastic moduli of composite materials have traditionally been made on either small specimens cut from a iar ger component or by using a scanning technique with the specimen immersed in a water bath. A phase-insensitive array has been developed for rapid nondestructive measurement of in-plane elastic moduli. The array characteristics allow for determinat ion of energy flux deviat ion angle in the composite, as well as measurement of group and phase velocity. Techniques for computing the phase velocity from array measurements are described.
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