Abstract
During Thermal Spraying material is partially or totally melted in between milliseconds, accelerated to high velocities and propelled onto the surface to be coated. Different temperatures, velocities and cooling times of the particles arise from different spraying techniques and conditions. The microstructure can be widely varied by tuning the spraying parameters. To optimize the coating properties with respect to a specific function one has to know i) the influence of the spraying conditions on the microstructure and ii) the correlation between microstructure and coating properties. Therefore analyzing methods are needed to determine the microstructure and to characterize mechanical, physical and chemical properties of the coatings. The proposed paper summarizes methods to characterize the microstructure including metallographic techniques, electron microscopy and X-ray analysis. Methods to determine the properties of the coatings including various adhesion tests, residual stress measurement, tribological and corrosion tests will be described in more detail. The increasing importance of Quality Management in all industrial sectors call heavily for reliable, destructive and especially non-destructive characterization techniques of coatings. An overview of common characterization techniques as well as new trends will be given. Recent development of International standardized tests will also be reported.
