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This paper presents two infrared thermography methods with CO 2 Laser excitation and microwave excitation applied to defect detection in CFRP. The tests were conducted with two specimens, one with defect, and another one without defect. On two concrete plates 40 cm × 40 cm × 4.5 cm were reinforced by CFRP; the defects were made by the absence of adhesive on an area 10 cm × 10 cm. The specimens were heated by microwave, generated by a commercial magnetron of 2.45 GHz and guided by a pyramidal horn antenna, with a power of 360 W within 150 s. Another series of the tests was conducted with CO 2 Laser, wavelength 10.6 µm, by heating the samples with a power of 300 W within 40 s. An infrared camera sensitive to medium waves in range of 3-5 μm, with a detector of 320 × 256 matrix detector in InSb (Indium Antimonide), was used to record the thermograms. As a result, the CO 2 Laser excitation is better for the delamination detection in CFRP. This study opens interesting perspectives for inspecting other types of defects in materials sciences; the microwave excitation is suitable for the deep defects in the materials whereas the CO 2 Laser excitation is better for the defects near the surface of the materials.

This paper presents a NDT method by infrared thermography with a microwave excitation system applied to the detection of metallic parts: a metal ring behind a wooden plate of 1cm thick, a reinforcement bar in front of a concrete wall and the detection of reinforcement bars equally spaced in a concrete slab of 6.5 cm thick. The excitation device is based on a magnetron associated with a horn pyramidal antenna. A contrast algorithm applied to the sequences of thermograms highlights metal ring or bars location.

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