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Mg-based alloys became a material of interest for biomedical applications. The major difficulty in the Mg-based alloy application is its rapid corrosion rate. Various coating methods are used to form a barrier layer onto Mg-based materials. In this work, a thin film of calcium phosphate was deposited on an Mg–0.8 at % Ca alloy using RF magnetron sputtering. As-deposited coatings were in an X-ray amorphous state. Post-deposition heat treatment resulted in the coating crystallization, exhibiting the pure HA phase. Heat-treatment at 450°C for 3 hours did not significantly change the coating integrity and adhesion strength to the Mg–0.8 at % Ca substrate. The Ca/P ratio, however, was changed from 1.85 for as-deposited to 2.00 for heat-treated samples. Both coating and substrate material after heat treatment exhibit preferential crystallographic growth in (002) direction with Tc(002) = 2.86 and 5.79, correspondingly. [ABSTRACT FROM AUTHOR]

The surface modification of implants became of vital importance for medical field. One of the promising techniques allowing to deposit biocoatings with tailored properties including antibacterial activity is an RF magnetron sputtering. The material of the sputtering target that is going to be deposited on the surface of an implant can be made from various calcium phosphates. Here we present the results of Zn- and Cu-substituted hydroxyapatites and pure hydroxyapatite materials synthesised by mechanochemical method that were sintered in the form of targets for subsequent RF magnetron sputtering. With a set of analytical methods and physico-mechanical testing including X-ray diffraction analysis, energy-dispersive spectroscopy, microhardness measurements and the texture analysis it was shown that the approaches and regimes described in the paper allowed us to produce targets with desired phase composition and good mechanical properties. We estimated the influence of specific surface area of initial calcium phosphate powder with various hydroxyapatite compositions on sintered targets’ microhardness. It is concluded that the use of powders with specific surface area in the range of 40-60 m²/g is beneficial for formation and sintering of targets with high physico-mechanical parameters. [ABSTRACT FROM AUTHOR]