Monitoring of the State of Paint Coatings by the Method of Digital Speckle Pattern Interferometry

摘要

The influence of liquid aggressive medium on a polyurethane paint coating (PC) is studied by the method of digital speckle pattern interferometry. For this purpose, we developed an experimental installation based on the Twyman–Green interferometer for the corrosion monitoring of PC. The installation was used for recording and subsequent processing of the difference patterns of speckle interferograms (SI) of the coating surface under the action of a 3% NaCl solution for 7, 14, and 21 days. It is shown that the difference patterns of SI can be used to analyze the time dependences of the deformed state of the PC surface and the growth rates of corrosion defects and exfoliations.