Thermographic detection of corrosion delamination

The initial stages of corrosion or delamination usually occur under the coating system , undetectable by visual inspection. However, these defects can be detected by transient thermography: The surface is subjected to a short heat pulse, and the subsequent temperature decay is recorded with a high lateral resolution. Thus, subsurface defects show as hot or cold spots. The method is also suitable to record the homogeneity of the coatings thickness.