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Thermal spraying using liquid feedstock has emerged as a promising technology for the deposition of finely structured ceramic coatings. In order to provide a comparative assessment of the deposition mechanisms occurring when spraying suspension or solution feedstock, suspensions of 300 nm-sized ZrO2–4.5 mol.% Y2O3 particles dispersed in water and in ethanol and solutions of zirconium and yttrium salts, corresponding to ZrO2–4.5 mol.% Y2O3 and ZrO2–8 mol.% Y2O3 stoichiometries, were processed by plasma spraying using different parameter settings. In-flight diagnostics of sprayed droplets, together with the morphological, microstructural and phase analysis of individual lamellae collected onto polished substrates, performed by SEM, FIB, AFM and micro-Raman spectroscopy, led to the identification of deposition mechanisms, which were subsequently verified through the characterisation of complete coating layers

Over a century of scientific research on the sliding friction of ice has not been enough to develop an exhaustive explanation for the tribological behavior of frozen water. It has been recognized that ice shows different friction regimes, but a detailed description of all the different phenomena and processes occurring at the interface, including the effect of surface roughness of both the ice and the antagonist material is still missing. In this work the effect of surface morphology on the friction of steel/ice interfaces is studied. Different degrees of random roughness on steel surfaces are introduced and the friction coefficient is measured over a wide range of temperature and sliding velocity. Correlation between the surface roughness and the lubrication regime and friction coefficient is discussed. A theoretical model is developed in order to explain this correlation, and to control the tribological behavior of the system by a proper selection of surface roughness parameters.