A new crosslinking system based on azide‐functionalized random copolymers has been defined for the preparation of substrates with controllable surface interactions. The azido group is used for both thermal‐ and photo‐crosslinking, which is found to be very efficient. Furthermore, the use of UV irradiation for crosslinking enables the preparation of patterned surfaces by conventional photolithographic techniques, combining the “bottom‐up” self‐assembly of block copolymer strategies with traditional “top‐down” photolithographic methods.

Optically excited Lockin-Thermography is a non-contact NDE-method which found many applications. However, the depth information about thermal boundaries (i.e. defects) which is included in the resulting phase angle images has not been extracted rigorously till now. This paper shows one way to derive from phase angle values depth resolved information on thermal boundaries and perform single-sided thermal wave profilometry.

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Organic coatings in the automobile industry have to resist corrosion and mechanical damage from stone chipping. Currently, no tool is established in industrial non‐destructive applications for analyzing the damage of stone‐impacts and the following corrosion after accelerated corrosion tests. Measurement methods such as the scanning Kelvin probe can analyze the corrosion progress in a detailed manner, but with a long measurement time. The pulsed phase thermography (PPT) is a non‐destructive tool to analyze inhomogeneities and defects in materials, with a huge field of applications existing. The present work shows advances in using the PPT to detect propagation of corrosion under coatings. Physical principles of the mechanism of the corrosion detection under coatings are described. Results of measurements of organic coatings on carbon steel as well as of organic coated galvanized steel show the corrosion propagation. Influencing factors to the measurement such as the thickness of the coatings are investigated, but no significant effect on the quality of the analysis was found. The corrosion progress can be monitored by the PPT fast and reliably. The achieved results correlate with the theoretical basis and the test results after surface characterization and destructive analysis of samples.

Lockin thermography is a reliable and fast NDT-technique that can be applied for a wide range of testing problems in aerospace applications. It is robust and sensitive enough to be used in industrial environments. Many different excitation methods based on specific physical mechanisms can distinguish between defective and intact material. Optically excited thermography, for instance, can detect boundaries, like delaminations, whereas ultrasound excited thermography is sensitive to inner friction and therefore defect-selective. The paper describes the principle of optically, ultrasound, and eddy-current excited thermography and presents several applications to typical aerospace structures.