Mechanical and structural characteristics of atmospheric plasma-sprayed multifunctional tio2 coatings

Abstract

Titanium dioxide (TiO2) is a multifunctional oxide that is an interesting material for many technological applications. This paper presents the mechanical properties and microstructure of TiO2 coatings resistant to dry sliding friction, corrosion, grain abrasion and erosion of particles at operating temperatures up to 540 degrees C. Layers of TiO2 coatings have been successfully deposited on test samples of steel C.4171 (X15Cr13 EN10027) using the atmospheric plasma spray (APS) process with plasma gun distances of 100 mm and 110 mm from the substrate. The APS procedure is used to produce relatively thick coatings of biocompatible and antibacterial TiO2 ceramic coatings for orthopedic applications. The coatings were deposited using the Plasmadyne company plasma spray system and Metco TiO2 powder, whose particles have an angular morphology produced by the melting and grinding cast blocks. The evaluation of the mechanical properties of the layers was made using the microhardness testing method HV0.3 and the tensile bond strength by tension testing. The analysis of the microstructure of the sprayed TiO2 coating layers was made in accordance with the Pratt & Whitney standard, using optical microscopy (OM). The morphology of the powder particles, the surface of the deposited coating and the coating fractures were examined by scanning electron microscopy. Tests have shown that the layers of TiO2 coatings deposited with a plasma spray distance of 110 mm have good mechanical properties and microstructure, which allow its use in the development of biomedical implants.