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Infrared thermography : principle and applications to aircraft materials

Infrared thermography is an NDT technique allowing the fast and safe inspection of aerospace materials. The active approach requires an external source of energy to produce a thermal contrast between the defective and the non-defective material. Several types of energy can be employed depending on the application. In this paper, the different active techniques are described and experimental results obtained by optical, mechanical and electromagnetic excitation are compared using a sandwich panel containing some of the most common types of defects found in aerospace components. Some insights are provided concerning the selection of the energy source for particular applications.