" Influence of Plasma Radiation on Temperature Measurement of In-flight Particles in Suspension Plasma Spraying "

The temperature of in-flight particles in plasma spraying is one of the main parameters affecting the coating microstructure. Temperature measurement has been carried out before for in-flight particles in air plasma spray (APS) and other thermal spray processes. Suspension plasma spray (SPS) is an emerging coating deposition technology that permits the deposition of nanostructured coatings with unique structural characteristics. The aim of this work is to evaluate the influence of radiation emitted by the plasma and vapors on temperature measurement of SPS particles performed by two-color pyrometry. To do so, spectroscopic analysis in the visible to near-infrared range is carried out on the jet stream when suspension of 20wt% YSZ particles in ethanol is sprayed. The analysis takes into account the radiation scattered by the particles (Mie scattering) as well as the radiation directly detected from the jet stream.