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Four various methods of powder feedstock preparation for laser powder bed fusion are compared. Application of commercial spherical powder leads to the formation of single-phased state. Powder mechanically alloyed during 14 minutes in air atmosphere provides conditions for the formation of double-phased state with nonuniform distribution of components in the samples. Mechanical alloying in Ar-atmosphere during 30 minutes leads to the formation of double-phased state with more uniform distribution of components and precipitations of Cr2O3. Preliminary mechanical sieving of the powder allows to produce double-phased samples with nonuniform distribution of components comparable with that in samples produced from powder mechanically alloyed during 14 minutes in air atmosphere. Microhardness of all the studied samples produced from all the studied powders was comparable. All the proposed methods of powder feedstock preparation are applicable in laser powder bed fusion depending on the required properties, elemental and phase composition of the final product.

The influence of the voltage of micro-arc oxidation on the physicochemical properties of the calciumphosphate coatings has been investigated. The linear growth of the roughness and hyperbolic decrease of the surface energy with growth of the oxidation voltage have been revealed. It was shown that the calciumphosphate coatings have low contact angle and high surface energy and, as a consequence, are hydrophilic. The optimal voltage range of the oxidation has been found. It varies from 200 to 250 V. This range provides the coating formation with the following specified parameters: surface roughness of 2 – 3.5 µm; contact angles with water and glycerol of 18 - 25º and 35 - 45º, respectively, and free surface energy of 73 - 80 mN/m.