Research of the structure and mechanical properties of microplasm porous coatings for biomedical purposes

The purpose of this work is to justify the feasibility of using the technology of microplasma sputtering from wire materials to obtain porous coatings for biomedical purposes, the modulus of elasticity of which is close to the corresponding characteristic of human cortical bone tissue. Analyzed the influence of the technological parameters of the microplasma sputtering regime on the degree of porosity of the coating. As a result, it was found that a decrease in current strength and consumption of plasma-forming gas, as well as a decrease in the speed of feeding the sprayed wire into the plasma jet lead to an increase in the porosity of the coatings. Even though these parameters are interrelated, for each individual material are limited by certain limit values, in case of non-observance of which the stable process of melting and dispersion of the sprayed wire in the plasma jet becomes impossible. Established  the  limit  parameters of the microplasma sputtering process for titanium alloy VT1-00 and zirconium alloy KTC-110, which allows obtaining a coating with maximum porosity. Conducted studies of the adhesion strength of the obtained  coatings, formed through a low-porous sublayer, with the maximum degree of porosity according to the ASTM C633-13 (2017) method which proven that the indicators of the adhesion strength of the coatings to the VT6 titanium alloy base at normal separation meet the requirements of the international quality standard ISO 13179- 1:2021. 

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