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.

<abstract> <p>This article describes the structure and properties of the developed hybrid composite Hastelloy X (NiCrFeMo)-AlMoNbTaTiZr-cBNSiCNiAlCo. The composite was obtained by the high velocity oxygen fuel spraying (HVOF) method in a protective atmosphere with a subsequent high-temperature thermomechanical treatment. In order to obtain new information about the structure, we studied the metallophysical properties of the composite using electron microscopy and X-ray diffraction analysis, as well as the mechanical properties and phase composition. We studied the influence of high-energy mechanical processing of high-entropic and ceramic materials on the structural-phase state and composite quality. We determined the optimal technological parameters of HVOF in a protective atmosphere, followed by a high-temperature thermomechanical treatment. Additionally, we optimized these parameters to form a hybrid composite providing the highest adhesion and low porosity. Moreover, we investigated the microhardness of the composite layers. On the basis of complex metallophysical studies, we examined the composite formation. In order to determine the endurance limit in comparison to various other composite materials, we carried out cyclic endurance tests of the developed materials.</p> </abstract>

Hybrid composite materials can successfully solve the problems of reliability, durability, and extended functionality of products, components, and details, which operate under conditions of multifactorial influences (temperature, force, and deformation). The authors have developed a hybrid composite high-entropy AlCoCrCuFeNi material and ceramic cBNCoMo(B4CCoMo) layer. The formation of hybrid composites was carried out using new technology. This technology includes high-energy machining, high-velocity oxygen-fuel spraying in a protective environment, high-temperature thermomechanical treatment, and heat treatment. The use of the developed technology made it possible to increase the adhesive strength of the composite layers from 68 to 192 MPa. The authors performed an assessment of the structural parameters of the composite layers. The assessment showed that the composite layers had a nanocrystalline structure. The research included mechanical tests of the hybrid composites Hastelloy X (NiCrFeMo)—AlCoCrCuFeNi—cBNCoMo and Hastelloy X (NiCrFeMo)—AlCoCrCuFeNi—B4CCoMo for cyclic durability (fatigue mechanical tests) and friction wear. The use of surface-layered materials AlCoCrCuFeNi—cBNCoMo and AlCoCrCuFeNi—B4CCoMo in the composition of hybrid composites significantly increased cyclic durability. The use of surface-layered materials in the composition of hybrid composites made it possible to reduce wear intensity. The test results show that the developed composites are promising for use in various industries (including oil and gas), where high strength and wear resistance of materials are required.