Wear process monitoring of thermal spray coatings and surface topography analysis using confocal laser scanning microscopy

In this article, the wear properties of a new generation of HVOF thermal spray coatings are investigated by analyzing the change of the surface topography before-and after the wear tests. The measurement of the surface topography is realized by an optical metrology method using a confocal laser scanning microscope. Firstly, the specific experimental setup is introduced for the purpose of conducting a reproducible data acquisition, which enables the precise relocation of the same specimen for the measurement after wear tests. Afterwards, a comprehensive surface topography study by extracting the key parameters such as roughness parameters, surface features and fractal dimension is conducted both for the original surfaces and worn surfaces. Finally, the correlations between the setups like load, wear speed, wear duration etc. of the tribometer and topographical variations after wear tests are presented.