Chemistry Project Abstract
INVESTIGATION OF REINFORCED CARBON-CARBON MATERIAL USING ULTRASONIC WAVE PROPAGATION
Presenter:
Jeffrey A. Chang, Illinois Mathematics and Science Academy, 1500 West Sullivan Road, Aurora, IL, 60506; neoeagle@imsa.edu
Mentor:
Dr. William Ellingson, Argonne National Laboratory Energy Technology Division, 9700 S. Cass Avenue, Bldg. 212, Argonne, IL, 60439; 630-252-5068 ; 630-252-5064; ellingson@anl.gov
Abstract:
In the wake of the loss of space shuttle Columbia more than one year ago, effective and practical nondestructive evaluation (NDE) methods for the orbiter that can assess damage levels are crucial for safe flight. The wing leading edges and nose cap of the shuttle are composed of a material known as reinforced carbon-carbon (RCC), which protects the spacecraft’s aluminum primary structure from the intense heat of atmospheric reentry. Obviously, any damage or deterioration of the RCC that compromises the integrity of this thermal protection system would threaten the safety of the entire shuttle and its crew. One-sided air-coupled ultrasound has already been demonstrated to be a useful NDE method for detecting visible physical anomalies on the surface of various materials, including RCC. Hopefully, with further development, it can also be used as an efficient tool for determining amounts of mass loss – internal RCC damage that can occur as the material endures high temperatures for extended periods of time. Air-coupled ultrasound was used to investigate a series of RCC samples with simulated impact damage, which were placed in a controlled high-temperature furnace for varying durations. The pre- and post-furnace samples were inspected, as well as RCC material previously exposed to flight conditions.