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Fluorohypsum is a solid, large-tonnage waste generated during the production of hydrofluoric acid. The volume of accumulated waste in the world is hundreds of millions of tons, which makes its utilization an increasingly urgent task. This article presents the results of research aimed at the use of fluorohypsum as a component of building materials. On the basis of the obtained data, the technological scheme of manufacturing products based on anhydrite binder is developed. It was established that the introduction of specialized additives into gypsum–anhydrite mixtures significantly increases the bond strength with the base (up to four times). The mixture of gypsum and anhydrite with a 75/25 arrangement provides tensile strength of up to 4.3 MPa and bending strength of 1.8 MPa, which exceeds similar indicators for traditional building materials. An economic analysis has shown a 20–25% reduction in the cost of composite production compared to the use of natural gypsum, which provides cost savings and makes these materials competitive.

In modern materials science and surface engineering, reactive plasma spraying (RPS) holds a key position due to its ability to create high-quality coatings with unique properties. The effectiveness of this process is largely determined by the physicochemical characteristics of the initial powder materials. This study examines the effects of mechanical activation for two compositions in the TiSiCN system and their impact on the quality and performance characteristics of RPS-produced coatings. It is shown that mechanical activation induces significant changes in the crystalline structure of the powders, reducing their particle size and increasing their specific surface area, thereby enhancing the reactivity of the materials during mechanochemical reactions. These changes contribute to the formation of dense and durable coatings with improved hardness and thermal stability. Thermogravimetric analysis (TGA) results confirm that the powders retain stable thermal properties and exhibit resistance to oxidation and decomposition. X-ray structural analysis reveals multiphase structures, including TiC, SiC, and TiCN, with the TiCN phase playing a key role in ensuring coating hardness. Additionally, SEM analysis showed that the TiSiCN-2-2 coating possesses a denser and more homogeneous structure with minimal pores and microcracks, providing superior mechanical strength and wear resistance compared to TiSiCN-1-2. Cross-sectional micrographs further revealed that the TiCN + Si coating has a greater average thickness (39.87 μm) and more uniform distribution compared to Ti + SiC (35.48 μm), indicating better application control and a more homogeneous material structure. Mechanical activation significantly influences the properties of powders, allowing for the determination of optimal parameters for RPS, which is a highly efficient method for creating coatings with unique performance characteristics.

The paper presents the results of the study of tungsten surface structure modification under helium plasma irradiation. It is revealed that during irradiation of samples, surface modification in the form of relief development as a result of irradiation is observed. X-ray phase analysis showed that no new phases of the W system were found after irradiation, only an increase in the intensity of diffraction lines was observed. There are significant differences in the microstructure of tungsten depending on the temperature of helium plasma irradiation in the above range. It is assumed that the cause of defects is the extremely low solubility of helium in tungsten. Metallographic analysis has shown that at irradiation of tungsten samples in time modes 1 and 1.5 hours, the degree of relief development is not high in comparison with the tungsten sample irradiated in the 0.5-hour mode. The greatest increase in surface roughness of the sample irradiated for 1 hour was registered, which is associated with the formation of small cracks, bubbles, and pores in the surface layer. At the same time, in the samples irradiated for 1.5 hours, the surface of which is characterized by chaotically located protrusions and depressions of various shapes, the roughness parameter Ra was 0.0603 μm. It was found that at temperature regimes T = 1200°C and T = 1500°C, the microhardness of tungsten increases by 10% and 11%, respectively.

The technology for obtaining hydrofluoric acid and the peculiarities of its production were studied, and the physical and chemical properties of the waste were examined. Activators that accelerated the hardening of the anhydrite binder were selected. The process of recycling fluorine hydrite waste from the production of hydrofluoric acid at Ulba Metallurgical Plant JSC was studied, and anhydrite unburnt binder with a setting time of 30 min was obtained. On the basis of the obtained data, a technological scheme of anhydrite binder production was developed. The effectiveness of the technological scheme was confirmed experimentally. This work aimed to study the possibility of the integrated use of secondary and anthropogenic raw materials from Ulba Metallurgical Plant, which represents an important means of not only increasing production efficiency and economic benefits and reducing the irrational alienation of land resources, but also protecting against the pollution of water and air basins, as the environmental policy of UMP JSC is nowadays of great importance.

In recent decades, great efforts have been made to significantly improve the performance characteristics of high-speed steel using various surface hardening techniques. Electron beam modification is engaging because it has an exceptionally high thermal efficiency and can significantly improve steels’ physical and mechanical properties. This work is devoted to researching the fine structure and changing the structural phase state of the surface layer of R6M5 high-speed steel after exposure to an electron beam. Electron beam treatment of steel R6M5 was carried out on a vacuum installation. The structure and phase composition of P6M5 steel samples were studied by transmission electron microscopy. Determined that after electron irradiation, the steel structure as in the initial state consists of martensite, carbides and residual austenite. After electron irradiation, an increase in the volume fraction of lamellar martensite is observed: the fraction of lamellar martensite in the initial state is 80%, and after irradiation, it is ~90% of the total fraction of α′-martensite. The action of the electron beam led to an increase in internal stresses in α′-martensite. Revealed, the value of the scalar dislocation density in R6M5 steel after exposure to an electron beam is higher than in the initial state. A cardinal difference in the state of the material after exposure to an electron beam is the presence of bending extinction contours in all M6C carbide particles.