Coating surfaces is one of the most common strategies for slowing down the destructive corrosion process on industrial heritage buildings. These coatings are subject to continuous degradation and must be renewed once they reach a certain condition in order to ensure intact protection against the progression of corrosion. In this project, the possible applications of active thermography for monitoring the condition of the aforementioned coatings will be tested using a number of typical fault patterns.

Active thermography offers a number of advantages in this context as a contactless and non-destructive method. The surface of the object is specifically stimulated by an external heat source. The resulting temperature distribution on the surface is recorded and analyzed using an infrared camera. Homogeneous and intact layers show uniform cooling, while defects such as under-rusting or layer detachment lead to thermal anomalies. This means that damage can potentially also be detected under visually intact coatings.

The size of the objects and surfaces makes it necessary to use highly mobile technology, such as drones, for practical and economical application. However, this technology places additional demands on the platform in terms of weight, stabilization, and efficiency of the measuring and excitation equipment, among other things. The selection of suitable excitation methods and parameters, as well as the adaptation of detection technology to the requirements of drone or UAV (unmanned aerial vehicle) operation, are therefore key aspects of the future methodology. To this end, typical defects that occur in historical industrial facilities (e.g., crack infiltration, blistering, or incomplete adhesion) will be simulated in laboratory tests in order to systematically evaluate the sensitivity and significance of the method.

The aim is to develop a robust thermographic testing method suitable for UAV use that is suitable for both preventive maintenance and condition assessment in monument preservation.