Зависимость морфологии, структуры, состава и биосовместимости Са- и Р-содержащих покрытий TiO 2 от параметров процесса плазменного электролитического окисления титана

The study covers the influence of bipolar pulsed regime parameters of titanium plasma electrolytic oxidation (PEO): voltage (U), pulse duration (t) and pause duration between pulses on the structure and morphology of TiO2 coatings doped with Ca and P. Threshold values of voltage (U1) and positive pulse duration (t1), which led to pore-free coating formation, were determined. It was shown that an increase in U1 leads to an increase in pore size and Ca and P concentration in the TiO2 coating. A relationship between rutile content in the coating and Ca and P concentrations was identified. It was found that the size and distribution of pores depend ont1. A structure with fine pores evenly distributed over the sample area is formed during a short positive pulse. An increase in t1 leads to the formation of a structure with unevenly distributed large pores. An increase in the values of U2 and t2 leads to a decrease in Ca and P concentrations and rutile content in the coating. It was shown that the surface of PEO TiO2 coatings ensures the growth of crystallites of (Ca, P)-containing phases when kept in a simulated body fluid solution. It was found that the amount of an apatite-like layer depends on the content of Ca and P in the TiO2 layer, as well as the size and distribution of pores.