Composition, structure and mechanical properties of the titanium surface after induction heat treatment followed by modification with hydroxyapatite nanoparticles

Coatings of titania (TiO2) and "titania–hydroxyapatite" were prepared by oxidation of commercially pure titanium VT1-00 using induction heat treatment (IHT), followed by modification with colloidal hydroxyapatite (HAp) nanoparticles. The IHT treatment was performed at temperatures within 600–1200 °C for 300 s. According to the results of scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray fluorescent analysis (EDX), nanoindentation and in vitro testing, titania coatings of high morphological heterogeneity, and high mechanical properties and biocompatibility were formed on the titanium surface after IHT. The coatings were found to consist of nano- and submicron crystals of oval, needle-like, plate and prismatic shapes. A subsequent modification with HAp nanoparticles of the coated titanium substrate leads to accelerated formation of mechanically strong oxidebioceramic composite coatings. It was established that the porous oxide coatings modified with nanoparticles of HAp that were formed at temperatures from 800 to 1000 °C and holding for at least 30 s had a high biocompatibility.