This paper discusses the technology, structure and functional–mechanical properties of surface layers made of high-entropy materials with a high-temperature shape memory effect, nickel (Ni)–cobalt (Co)–titanium (Ti)–zirconium (Zr)–hafnium (Hf), nickel–copper (Cu)–titanium–zirconium–hafnium and titanium–nickel–zirconium–hafnium–cobalt–copper. The developed technology and equipment for the formation of high-entropy coatings on the surface of steel products included mechanical activation of powders, high-velocity oxygen fuel (HVOF) spraying in a protective atmosphere and subsequent thermal and thermomechanical treatment. This allowed carrying out this process in a single technological cycle. The authors have developed statistical models of the formation process of highly entropic HVOF coatings in a protective atmosphere according to the criteria of adhesive strength and porosity with optimization of parameters. Based on complex X-ray diffraction and electron microscopy studies, the authors determined the structural parameters of high-entropy alloy coatings obtained by HVOF, followed by thermal and thermomechanical treatment. It was shown that all three alloys, nickel–cobalt–titanium–zirconium–hafnium, nickel–copper–titanium–zirconium–hafnium and titanium–nickel–zirconium–hafnium–cobalt–copper, which make up the surface compositions, are in an austenitic–martensitic state with a grain size of 32–120 nm. The authors performed calorimetric studies of the functional properties of the coatings. The studies showed the manifestation of austenitic–martensitic transformations. The authors also carried out tests for ‘friction wear’ and mechanical multicycle fatigue of the obtained high-entropy compositions on a steel surface.

中文翻译：

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HVOF合成高熵涂层的结构行为和力学性能

本文讨论了由具有高温形状记忆效应的高熵材料制成的表面层的技术，结构和功能机械性能，其中镍（Ni）-钴（Co）-钛（Ti）-锆（Zr）- （（Hf），镍-铜（Cu）-钛-锆-ha和钛-镍-锆-ha-钴-铜。用于在钢铁产品表面形成高熵涂层的先进技术和设备包括粉末的机械活化，在保护性气氛中喷涂高速氧气燃料（HVOF）以及随后的热和热机械处理。这允许在单个技术周期内执行此过程。作者根据粘合强度和孔隙率的标准，通过优化参数，开发了保护气氛中高熵HVOF涂层形成过程的统计模型。基于复杂的X射线衍射和电子显微镜研究，作者确定了通过HVOF进行热处理和热机械处理后得到的高熵合金涂层的结构参数。结果表明，构成表面成分的所有三种合金（镍-钴-钛-锆-,、镍-铜-钛-锆-ha-钛和钛-镍-锆-ha-钴-铜）均处于奥氏体-马氏体状态，晶粒尺寸为32-120 nm。作者对涂层的功能特性进行了量热研究。研究表明了奥氏体-马氏体相变的表现。作者还对钢表面上获得的高熵成分的“摩擦磨损”和机械多周期疲劳进行了测试。