Titanium and its alloys are common materials used for biomedical implants. These materials are valued for their overall mechanical properties, and generally little adverse reactions in a biological environment. Functionalisation of the biomedical alloys by depositing nanostructured oxide coatings dramatically effects the biological response of implants, and often improve their biocompatibility. Nanostructured coatings mask the difference in the chemical composition of the substrates, and impose an additional surface topography at nanoscale. It has also been demonstrated that the success or failure of these materials as implants is very strongly connected with the adhesion, composition and structure of the oxide layers, surface contamination, and surface topography. Surface treatment of biomedical alloys before coating plays often a crucial role in the coating's performance. First results of the chemical solution deposition of nanostructured T1O2 coating on the electrolytic plasma polished (EPP) titanium alloys are presented in this work. The capabilities of the electrolytic plasma to polish and modify the surface of titanium alloys are demonstrated. The EPP method is based on the chemical and physical processes occurring at the electrode surface immersed in a low-concentration non-acid electrolyte, during applying the direct current voltage in the range of 100 - 600 V. Chemical solution deposition with and without the electric field has been utilized for synthesizing titania based coatings from solutions of alcoxides or inorganic salts, followed by thermal annealing to crystallize the coating material. Our preliminary results show that chemically deposited and annealed dense 100-200 run thick titania coatings on EPP titanium exhibit smaller grain size and better adhesion than the coatings on mechanically polished substrates. The coatings have favorable for biomedical applications rutile structure, however further studies of the corrosion and wear resistance, as well as the cell response are needed to optimize the both processes of electrolytic plasma treatment and titania coating deposition.
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