Nondestructive Evaluation of Thermal Sprayed Coatings by Pulse Heating Infrared Thermography

Abstract

The inner wall of boilers used in thermal power plant is damaged by high-temperature corrosion and ash erosion. For protecting these damages, the inner wall of heat exchanger tubes of boilers is covered by thermal sprayed coatings. These coatings are regularly inspected and repaired for safety operation of boilers. However, conventional inspection techniques are insufficient in the light of accuracy and efficiency. In this study, pulse heating thermography is examined as a new technique for defect inspection and coating thickness measurement.