Thermographic Detection of Defects in Refractory Composites

Significant effort and resources are being expended to develop ceramic-matrix composite (CMC), metal-matrix composite (MMC), and polymer-matrix composite (PMC) materials for high-temperature engine components and other parts in advanced aircraft. The development of composite materials is also being pursued actively in the automobile and sporting-equipment industries, among others. A portion of the development effort involves the assessment of nondestructive-evaluation (NDE) techniques for detecting flaws in these materials. Recent advancements in infrared-camera technology and computer power have made thermographic (infrared) imaging systems worth reconsideration as reliable tools for NDE of these materials. Thermography offers the advantages of real-time inspection, no contact with samples, nonionizing radiation, capability for inspection of samples with complex shapes, variable sizes of fields of view, and portability.