University of Maine

High-Temperature NDE and Characterization of Carbon-Composites

PI: Michael "Mick" Peterson
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DEPSCoR Project supported by Missile Defense Agency through the Office of Naval Research,
Dr. Yapa Rajapakse Science Officer

Overview

High Temperature Materials Characterization

The focus of this research is on the development of a new sensor technology that is suitable for high temperature materials characterization. The sensor and associated technology will provide real-time information on the elastic properties of a general anisotropic material. Advancement of technologies such as those proposed for the Advanced Interceptor Technology (AIT) and similar program are pushing the thermal thresholds of materials to new levels. If materials are to be used at these very high temperatures, novel characterization methods are required. At the same time the structural architecture of the composites must become further optimized to fully optimize the design. Structures must be designed to optimally load the material about multiple material axes. These sensors will make it possible to obtain a complete tensorial material characterization as a function of temperature.

The complete compliance tensor of the material will be obtained by using ultrasonic waves that propagate through buffer rods. The guided waves in the buffer rods consist of modes that may be dominated by either the shear or the longitudinal properties of the material. The guided waves propagate through orthogonal directions in the solid to produce measurements of ultrasonic velocity in the specimen. Even for the most general anisotropic material, the full elastic tensor can be recovered from the wave speed data by optimized recovery techniques.