Thickness Measurement of Functional Coatings on the Surface of Structural Parts: Key Technology and Advancements

doi:10.3901/JME.2025.23.292

Abstract

Abstract: The latest development of the thickness measurement technology of functional coating on the surface of structural parts is reviewed, and the key technical issues in the integration of coating thickness measurement and processing are discussed. Simultaneously, the needs of measurement accuracy and efficiency for coating thickness uniformity control are clarified. Firstly, the types of functional coatings and the characteristics of thickness measurement are systematically analyzed, and the requirements of measurement accuracy and measurement efficiency in the control of coating thickness uniformity are clarified. According to the requirements of the use environment, the structural surface of some parts of the aerospace aircraft is sprayed with functional coatings such as thermal protection, wave absorption and conduction. Distinct types of coatings have different physical characteristics. The quality requirements of the parts make the thickness measurement of the coating not only meet the high resolution and high precision, but also need to have sufficient detection depth and rapid measurement ability. Secondly, the application of thermal imaging technology, ultrasonic technology and magnetic eddy current technology in the measurement of functional coating thickness is introduced according to the measurement principle. The development status of thickness nondestructive testing technology for thermalprotective coating, wave absorbing coating and conductive metal coating is systematically analyzed. Then, according to the properties and characteristics of various functional coatings and the requirements of coating thickness measurement accuracy, the applicable thickness measurement methods and hardware system composition are introduced. Finally, the advantages and limitations of various thickness nondestructive testing technologies are analyzed, and the future development of thickness measurement technology of functional coatings on structural parts is prospected, providing a reference for the engineering applications of thickness measurement of functional coatings on structural parts.

Key words: functional coatings, thermal imaging thickness measurement, ultrasonic thickness measurement, eddy current thicknessmeasurement, coating polishing

CLC Number:

TG156

WU Tiange, GUO Guoqiang, WU Lili, KE Shuai, KONG Zhixue, ZHAO Huan, WANG Dazhong. Thickness Measurement of Functional Coatings on the Surface of Structural Parts: Key Technology and Advancements[J]. Journal of Mechanical Engineering, 2025, 61(23): 292-307.

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