EVALUATION OF DYNAMIC PROPERTIES OF A CARBON- CARBON COMPOSITE AT ELEVATED TEMPERATURES

Methods for in-situ monitoring of high temperature composite materials are important in a number of technological applications. In this work a method is developed that makes use of solid cylindrical waveguides to monitor the change of elastic properties and the oxidation reaction of carbon-carbon composites with change in temperature. The apparatus is designed to allow ultrasonic measurements to be performed in a controlled atmosphere at temperatures up to llOO°C. Signal processing required to obtain quantitative information is considered for the experimental apparatus described. ACKNOWLEDGMENTS I would first like to express my appreciation for my "thesis group", Miao Sun and Anthony Puckett for their patience, guidance, suggestions and encouragement during this intense process. I could not have completed this work without them. I would also like to thank my advisor, Dr. Michael "Mick " Peterson for the chance to work on this project. Many thanks go out to Sheryl Brockett and Richard Mewer who gave me the "It wil be over with soon " speech many times. I would like to thank them both fo