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electrolytic oxidation on titanium alloys for medical applications with a regulated
surface morphology (roughness, porosity) and a Ca/P ratio of 1.69, close to bone
tissue, was established.
6. For the first time, the bioactive composite coatings on the surface of titanium
alloys were developed by combining methods of diffusion saturation from a nitrogen-
oxygen-containing gas environment and PEO in an alkaline electrolyte (KOH +
hydroxyapatite), which increases the corrosion resistance in a physiological
environment by an order of magnitude and provides a Young's modulus value equal
to that of cortical bone.
Practical significance of the obtained results.
1. For the surface modification of spherical titanium (BT1-0) components of
endoprostheses, for the first time a stage nitriding regime, which provides a one-order
reduction of the wear intensity of the UHMWPE component in a blood plasma and a
6-fold reduction of the friction coefficient, was developed (patent of Ukraine for
utility model No. 159948 dated 24.07.2025).
2. The surface-modified titanium spherical component of the tribo-pair of an
artificial joint was tested using the stand-simulator of human biomechanical motion
T-24. It was established that the tribo-pair «nitrided titanium BT1-0 – UHMWPE»
provides a 3-fold greater resource compared to the widely used in implantology tribo-
pair «CoCrMo – UHMWPE».
3. The composition of the alkaline electrolyte (1M KOH + hydroxyapatite) and
the parameters of PEO (160 V, 1 min) in a pulsed regime of treatment for the
formation of bioactive hydroxyapatite coatings of regulated parameters (thickness up
to 100 μm, surface roughness of 1…2 μm and porosity of 14…16%) on the surface of
commercially pure titanium BT1-0 were proposed.
4. It was determined that the level of biocompatibility of composite
(oxynitride/HA) coatings is ensured by the formation of titanium oxynitrides with an
oxygen content of 60…65 at.%, and osseointegration is ensured by the formation of
a surface layer of hydroxyapatite with a Ca/P ratio close to bone tissue (1.67), with a
