Influence of critical plasma spraying parameter (CPSP) on plasma sprayed Alumina–Titania composite coatings

Plasma sprayed ceramic coatings are successfully used in many industrial applications, where high wear and corrosion resistance with thermal insulation are required. Critical plasma spraying parameter (CPSP) is a key factor to control the quality of coatings. In this study, Alumina–Titania composite coatings in different compositions (Alumina–3 wt.% Titania, Alumina–13 wt.% Titania and Alumina–40 wt.% Titania) were prepared by 40 kW atmospheric plasma spray torch at three different CPSP conditions (833.33, 1000 and 1166.66) and their influence on coatings and plasma jet temperature were studied. The phase, microstructure, sliding and erosive wear rates, microhardness and porosity of the different Alumina–Titania composite coatings was investigated and correlated to CPSP conditions. The result shows that increasing CPSP increases the hardness and anti wear behavior of Alumina–Titania composite coatings except Alumina–40 wt% Titania coating.