A non-destructive measurement method for thermal barrier coating thickness in a robot polishing process based on point cloud processing

作者：Yu Hu, Zhenhua Cai, Tingyang Chen, Shaopeng Niu, Chao Wang, Chunming Deng, Shujuan Dong, Ziyang Chen, Zhipeng Shan · 发表于：Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture · 年份：2024 · DOI：10.1177/09544054241276035 · 被引用次数：1 · 研究领域：Particle Dynamics in Fluid Flows、High-Temperature Coating Behaviors、Fluid Dynamics and Heat Transfer

The adhesion state between the bond coat and top coat of thermal barrier coatings (TBCs) is influenced by the surface roughness of the bond coat. Under certain operating conditions, polishing is employed to reduce the surface roughness of the bond coat, thereby enhancing the adhesion strength between the top coat and bond coat and improving the TBC’s resistance to high-temperature oxidation. In order to accurately control the thickness of the bond coat during the polishing process, this study proposes a non-destructive measurement method for coating thickness based on point clouds. By preprocessing, registering, and calculating the distance between the point cloud generated by laser scanning the turbine blade, the thickness of the bond coat was determined. The method exhibits greater accuracy in regions with small curvature variations. Compared to measurements obtained using a metallographic microscope, the maximum thickness deviation between the two methods is 4.004 μm, and the relative error is less than 5%. Experimental results demonstrate that this method can accurately measure coating thickness, offering advantages such as real-time processing, flexibility in application scenarios, high measurement efficiency, and relatively low requirements for coating materials.