Process-Microstructure-Property Relationships in Controlled Atmosphere Plasma Spraying (CAPS) of Ceramics

Thermal plasma spray processes with their various operating parameters can be considered as flexible technique to carry out appropriate ceramics coatings. This work deals with plasma spraying of several ceramics powders (hydroxyapatite (HA), Al₂O₃-TiO₂, Al₂O₃, ZrO₂-Y₂O₃ (YSZ) and Cr₂O₃) with suitable parameters using a CAPS system ("Controlled Atmosphere Plasma Spraying"). The HPPS (High Pressure Plasma Spraying), APS (Air Plasma Spraying) and IPS (Inert Plasma Spraying) modes were applied in order to obtain the suitable microstructure. The microstructures and phase compositions allowed to establish that surrounding high-pressure in the CAPS chamber is leading to a good heating of the powder and a good quality for the coatings.