Dependence of Particle Parameters in Flight and Coating Character on Power of the Electric Supply at Plasma Spraying of TiO<sub>2</sub>

Abstract

The influence of input power on the spayed powder and final coating was quantified for particular case of water-stabilized plasma spray torch (WSP®) and ceramic coating formed from titanium dioxide (TiO2). All other spray setup parameters were fixed during the experiment with electric supply power as the only variable factor. In-flight particles were characterized by Doppler particle velocimetry, microstructure of the coatings was observed by microscopic techniques and computer image analysis and phase composition was studied by X-ray diffraction. Various mechanical properties were measured – microhardness, surface roughness and wear resistance in a slurry. The results indicate that the higher power means better coating quality – its microstructure and mechanical performance. This substantial difference has the same trend for both power supplies utilized for the testing.