Effect of Plasma Spray Parameters on Thermal Barrier Coating Formation and Microstructural Properties

This study investigates the effects of plasma spray parameters on the microstructure and porosity of yttria-stabilized zirconia coatings. In the experiments, the torch was held in place perpendicular to the substrate to produce cone or stalagmite shaped deposits. Stand-off distance (80, 90, 120 mm) and spray time (15, 30, 60 s) were varied to assess their effect on microstructure-property relationships as well as particle temperature, velocity, and impact angle. The shapes of the deposits were recorded using a CMM and surface topography and roughness were measured with a 3D optical profiler.