Novel Approaches for the Ultrasonic NDE of Thick and other Composites
This paper summarizes several recent developments which are facilitating new approaches for both active and passive quantitative ultrasonic measurements in composite materials. These include the development of point sources and point receivers, a theory for analyzing the propagation of transient elastic waves through a bounded, dispersive and attenuative medium, and the development and implementation of appropriate signal processing algorithms. An alternative to these deterministic approaches is a processing scheme based on a simulated intelligent system which processes the signals like a neural network. Examples of applications of these ideas to the NDE of composite materials are shown.
KeywordsUltrasonic Signal Pattern Vector Viscoelastic Plate Quantitative Nondestructive Evaluation Transient Elastic Wave
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