INVESTIGATION OF THE STRUCTURE OF DETONATION COATINGS BASED ON CALCIUM PHOSPHATE COMPOUNDS

The process of osseointegration largely depends on the surface roughness, structure, chemical composition and mechanical characteristics of the coating. In this regard, an important direction in the development of medical materials is the development of new technologies for surface modification and the creation of bioactive ceramic coatings. Calcium phosphate materials based on hydroxyapatite are offered as bioactive ceramic coatings on titanium implants to effectively accelerate bone healing. The article discusses the results of a study of the formation of a hydroxyapatite coating on a titanium substrate during detonation spraying. The powders for spraying and the resulting coatings from hydroxyapatite were studied by Raman spectroscopy and X-ray diffraction analysis. It was determined that the appearance of α-Ca₃(PO₄)₂ phases is typical for a coating of pure hydroxyapatite obtained by detonation spraying, but the hydroxyapatite phase remains in the coating composition. The results obtained using Raman spectroscopy indicate that hydroxyapatite is the main phase in coatings. The morphology of the sprayed coatings was characterized using SEM, and the elemental composition of the coatings was analyzed using EDS. The EDS analysis showed that the elemental composition of the obtained coatings is similar to the elemental composition of the initial powder, which is very important for the characteristics of biocompatibility and preservation of the service life of coatings.

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