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Selective laser melting (SLM) is a manufacturing technology of metal parts of any shapes with target mechanical properties by means of laser melting. This paper discusses the effect of SLM parameters: laser output power, laser movement velocity, scanning pitch and preheating temperature of a powdered material on surface formation mechanism, namely, its physical configuration when melting cobalt-chromium-molybdenum powdered material Со28Cr3Mo. The study points at structural differences of melted surfaces even under identical process parameters. Several types of surface formation are identified, e.g. homogenous melt, coagulated particles, and shapeless particles. Vapor pressure, Marangoni effect, and heat effect of a melted powder are stated to be key reasons for rough surface. This research is of high importance for understanding the effect of SLM parameters on formation of a target quality surface, positive stability and repeatable accuracy of the process.

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 model of laser sintering with regard to explicit porosity evolution of powder layer has been suggested. Due to porosity reduction the shrinkage occurs, thermal - physical properties (the heat capacity, thermal conductivity coefficient) and reflection coefficient of laser irradiation change. It has been shown that additional mechanism of convective heat transfer connects with powder layer thickness evolution. It was detected that model obeys some prognostic properties and allows to reveal the area of technological parameters where homogeneous properties of sintered layer form.

The phase transformations of the alloy Ti-40 mas % Nb after tempering and severe plastic deformation are studied. The phase transformations of the alloy according to the type and conditions of external influences are analyzed using methods of XRD, SEM and optical metallography. It is determined that inverse phase transformation of the metastable α''-phase to equilibrium β-phase is carried out after severe plastic deformation. Complete phase transformation α'' → β is typical for the mode, which consists of three pressing operation with the change of the loading axis in cramped conditions, followed by a multi-pass rolling in grooved rolls.

The influence of the microarc oxidation parameters as electrical voltage and process duration on the surface morphology and topography, wettability and chemical composition of calcium phosphate coatings on the low elastic module Ti-40mas.%Nb (Ti-40Nb) alloy surface has been investigated. The linear growth of thickness and roughness and the linear decrease of the free surface energy with increasing process electrical voltage have been obtained. It was shown that calcium phosphate coatings have low contact angle with liquids and high free surface energy, as a consequence. It indicates a high hydrophilicity. X-ray diffraction analyses showed that the coatings after deposition have X-ray amorphous state that indicates high rate of coating dissolution. The coatings have maximum Ca/P ratio is 0.6. The optimal range of the oxidation voltage from 200 to 250 V and process duration from 5 to 10 min has been found. Such parameters allow to form the coating with the specific morphology, roughness and thickness and high hydrophylicity.

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.

Results of research of mechanical properties of calciumphosphate coatings produced by the method radio frequency magnetron sputtering on bioinert alloys of titanium, zirconium and were presented. Calcium phosphate coatings show high value of adhesion strength to bioinert metal surface. Calcium phosphate coating on titanium-niobium alloy surface shows the highest value of adhesion strength. Mechanical properties of a composite material based on bioinert alloy and calcium phosphate coating are higher than properties of the components of composite material separately.

Dislocation structures in the near surface layers of α-Fe produced by repetitively pulsed intense Hf ion beams with doses of 0.23 × 1016 to 24.0 × 1016 ions cm−2 were studied by electron microscopy. Both ion implantation and plasma deposition were used. Under such conditions the maximum impurity concentration of Hf in α-Fe appeared to be 70 at.%, the dose of implanted ions being determined from profile analysis of Hf distribution by the RBS method. A developed dislocation structure is formed by ion implantation in the near surface layer of α-Fe over a depth of 100 μm. The dislocation density reaches its maximum value at a depth of 5–7 μm from the surface and is increased by about 1–2 orders of magnitude from that in the initial state. Static tensions formed in the doped layer play a decisive role in the formation of the dislocation structure.