Abstract
New materials and manufacturing processes, and the quest for economy and user safety, have necessitated the development of nondestructive testing methods to quantify the life and reliability of a product during manufacture and service. Described herein, is a testbed to be used in the research and development of these testing methods. A brief motivation for using ultrasonics applied to nondestructive evaluation is followed by a chapter on the feasibility of using a unique testing method and animated data presentation on advanced composite materials. This testing method, conceived by the author, utilizes oblique injection of ultrasound into the specimen. Several cycles of the ultrasonic waveform radiated from the specimen downstream of the injection area is digitized and recorded. The data has three independent dimensions; cartesion location and time. The time variable is the key to the presentation of the data as an animated two dimensional image. It was this work that illustrated the need for a flexible scanning imaging research testbed, not only for the discussed method, of which it is an integral part, but for advanced development of other techniques. Software development and integration of off -the-shelf parts into a unified computer controlled testing facility is the contribution by the author in the second phase of this research. Chapters on the description of the system, an example showing the capabilities of the system analogous to traditional ultasonic C-scanning, accomplishments, and a look to the future conclude this thesis. The appendices include listings of the programs developed for the system, a manufacturer address list. A videotape of the animation data presentation is included as a second volume of this thesis.
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