Ultrasonic Phase Measurement for Coating Thickness Evaluation
Ultrasonic phase measurement measures phase shifts of reflected waves to precisely determine thin layers or corrosion protective coatings. It is an interferometric method.
Physicochemical mechanism of action
Ultrasonic waves are sent into the material surface and reflected. The phase shift of the returning waves is measured to calculate the coating thickness.
Metallurgical relevance & risks in welding
This measurement is especially important for checking corrosion protection coatings or thin films on materials. Incorrect measurements can lead to inaccurate results, which in turn can lead to insufficient or excessive corrosion protection.
Workshop practice & instructions
Use a high-resolution ultrasonic device with interferometric measurement. Make sure the wave direction is perpendicular to the coating surface. The measurement should be carried out under constant temperature and humidity conditions to obtain accurate results.