The results of experimental studies on the formation of the surface layers of a material with shape memory effect (SME) based on TiNi deposition of Pb-Bi melt at a temperature gradient of 600-1100 °C in an argon atmosphere. It is shown that this method allows to obtain uniform surface layers in nanostructured state and almost any thickness can be used for the formation of coatings on the interior surfaces of products of any shape with the stress concentrators. Structure, chemical and phase composition of the surface layers provide a manifestation of TiNi shape memory. The average grain size of TiNi coatings ranges between 60 ÷ 160 nm.

The authors developed technology for obtaining surface composite materials. This technology includes high-energy mechanical treatment, HVOF in a protective atmosphere, subsequent thermomechanical and thermal treatment of ZrCuNiCoTi, cBNNi3AlSiCCoY layers in a protective atmosphere. The processing allowed to increase the adhesive strength of the surface composites, reduce their porosity and improve their functional and operational properties. Staged methods of heat treatment and plastic deformation of surface layers have been developed. These methods stabilize material structure while reducing residual stresses. On the basis of complex X-ray diffraction and electron microscopic studies, the structural parameters of surface composites were determined. It was shown that the ZrCuNiCoTi alloy is in the austenitic-martensitic state and has a nanocrystalline structure with a grain size of 80–120 nm. Meanwhile, the cBNNi3AlSiCCoY alloy consists of many intermetallic phases and inclusions and has a nanosized structure with a grain size of 100–200 nm. A microhardness study of the surface layers in ZrCuNiCoTi – cBNNi3AlSiCCoY composite showed that thermomechanical treatment increases microhardness. The experimental data were statistically processed. As a result, empirical mathematical dependences of the stress amplitude on cyclic durability were compiled. Mechanical tests included tests of NiCoTiZrHf – cBNCoMo, ZrCuNiCoTi – cBNNi3AlSiCCoY, TiNiZrHfCoCu – cBNCoNiAlY composites for multi-cycle fatigue during bending with rotation.

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The article presents the assessment study of mechanical activation and mechanical alloying effect on the structure, phase state of the powder composition and of the coating based on it. The duration of mechanical activation was varied as follows: 1 h, 2 h, 4 h, 8 h, 16 h, 32 h. It is shown that in order to from a high-entropy FeNiCoAlNb alloy on the workpiece surface the duration of mechanical activation must be at least 4 hours. We described the mechanism of mechanical alloying and ways of accelerating this process.