Plasma sprayed YSZ coatings using liquid feedstock starting from submicron and nano-sized materials have lately attracted the research community interest resulting in layers with unique properties. Compared to conventional YSZ coatings starting from dry powders with a mean grain size of a few tenths of microns, they present featureless microstructure with absence of large splat boundaries - usual points for failure initiation and propagation - as well as uniform pore distribution which directly correlates to lower thermal conductivity and elastic modulus. From the wide range of applications among the most promising are Thermal Barrier Coatings in the aircraft engine industry and the development of Solid Oxide Fuel Cells.|
In this study, stable water-based YSZ superfine inks have been implemented in the Atmospheric Plasma Spray technique. Deposition of coatings using different critical spray parameters, on various substrates starting from different liquid feedstock achieving thickness ranging from a few ¼m to a few tenths of ¼m has been investigated. The resulting layers quality, microstructure characteristics, deposition rate etc. have been correlated to the investigated conditions. Through this research it is demonstrated that using the suspension plasma spraying technique, YSZ coatings with homogeneous microstructure and special characteristics can be developed finding numerous applications.
The work was financially supported by the Project EFECTS (EC FP7 Program).