Abstract
Thermal spray usually involves high temperatures in short times. This phenomenon is enhanced with the use of an HPPS system (Plazjet from Tafa). To spray a Zirconia coating, high powers are necessary such as 200 kW providing for the substrate an important increase in the surface temperature. Furthermore, the good quality of a thermal spray coating results in the low surface roughness, a satisfactory microstructure cohesion, a minimal distortion of the part when spraying on large sheets with a thick thermal barrier coating. Cooling with compressed air is widely used but other solutions are studied concurrently; CO2, nitrogen, and air; these gas are tested in different conditions of pressure and flow. Some improvements in terms of temperature in the coating and roughness have been found.