Comparison Of TiO2 Targets Manufactured By APS And Sintering Processes For PAPVD Coatings Suitable In Technological And Medical Applications

In surface science of functional oxides, Titanium dioxide (TiO2) is one of the most investigated crystalline systems either in rutile or anatase phases. The rutile phase is widely used in optical, microelectronic, tribological applications and in the conversion of solar energy. And the anatase phase is used in self-cleaning, anti-fogging, photo-catalytic, biomedical, self-sterilizing and anti-bacterial technologies. This work focuses on studying the required process conditions to obtain TiO2 targets by APS onto copper substrates using commercial TiO2 powders (Oerlikon Metco in Switzerland) with suitable physical and chemical properties for technological and medical applications as PAPVD coatings. APS targets were compared to sintered ones fabricated using the same powder. The raw powders were characterized by laser diffraction, SEM, XRF, XRD, TGA and DSC while the characteristics of the APS-deposited targets as well as the sintered ones were determined by SEM and XRD to identify constituent phases, the amorphous content and the crystallinity degree. This work allowed to confirm the advantages and limitations of both processes in terms of grain size, chemical composition, microstructural homogeneity and density in order to choose the best option to manufacture targets for PAPVD coatings for technological and medical applications.