This paper presents the results of a metallographic and tribological study of 86WC-10Co-4Cr coatings obtained by the HVOF method on the Termika-3 unit at varying spraying distances. The influence of spraying distance on the coating microstructure, phase composition, as well as mechanical and tribological properties, was studied. According to the results of the study, it was found that the optimum spraying distance for 86WC-10Co-4Cr coatings with improved wear resistance and hardness characteristics and low porosity is 300 mm.

In this work, the influence of the technological parameters of the detonation method on the formation of metal oxide compounds on the basis of titanium was investigated. The aim of the work was to investigate the method of the effective control of the phase composition and microstructure of titanium-based coatings during detonation spraying. The main parameters that varied in detonation spraying were the volume of filling the detonation barrel with explosive mixture and the oxygen/fuel ratio. The mechanism of formation of the gradient structure of coatings based on metal oxide compounds depending on the technological parameters of detonation spraying was considered. The structural-phase states and tribological properties of detonation coatings were investigated by the following methods: X-ray phase analysis (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX-mapping), profilometry, and the test for wear-resistance according to the “ball-disk” scheme. It is shown that the phase composition of coatings may significantly change relative to the initial titanium powder during the detonation spraying due to the interaction of particles of powders with components of the gas atmosphere. Varying the spraying parameters may control the chemical reaction and provide conditions for the synthesis of the desired phases in the coatings (titanium oxide TiO₂ and Ti₂O₃).

This study investigates the production of chromium–manganese ligature by a metallothermic process using complex silicon–aluminum reducing agents. Low-grade chromium and iron–manganese ores from the Kempirsai and Kerege-Tas deposits in Kazakhstan were used as raw materials, while the reducing agents included alumosilicomanganese alloy (AlSiMn) and ferrosilicoaluminum (FeSiAl). Thermodynamic calculations were performed with HSC Chemistry 10 at 1400–1800 °C and reducing agent dosages of 10–100 kg per 100 kg of ore charge. Crucible smelting experiments were then carried out in a Tamman furnace, followed by large-scale laboratory trials in a 100 kVA refining electric furnace to verify reproducibility, with a total of 14 runs. The chemical composition of the ligatures varied depending on the reductant: with AlSiMn the alloy contained Fe—23.14%, Cr—53.74%, Mn—20.03%, and Si—3.06%; with FeSiAl, it contained Fe—42.01%, Cr—25.74%, Mn—27.15%, and Si—5.05%; and with FeSiCr dust, it contained Fe—34.45%, Cr—21.45%, Mn—39.82%, and Si—4.24%. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses confirmed the presence of α-(Fe,Cr,Mn), FeSi, and Cr₅Si₃ phases. The results demonstrate the efficiency of complex silicon–aluminum reducing agents and the ability to regulate the composition of chromium–manganese ligatures by the selected reductant.

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.

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.

This work presents the results of the study on the effect of pulse-plasma treatment on the structural-phase states of the surface layer of detonation coatings based on Ti₃SiC₂. Structural-phase studies were carried out by three main methods: scanning electron microscopy, transmission electron diffraction microscopy on thin foils and X-ray structural analysis. It was determined that after the pulse-plasma treatment, an increase in the intensity of the Ti₃SiC₂ peaks was observed, and the appearance of new reflections (101, 102, 112, 204, 1110, 0016) of this phase was detected, which indicates the increase in the MAX-phase content. It was determined that after the pulse-plasma treatment, the fraction of voids (pores) and the particle area decreased and the microstructure became more homogeneous, which resulted in the densification of the Ti₃SiC₂-based detonation coating. It was found that the process of detonation spraying with subsequent pulse-plasma treatment resulted in the formation of a Ti₃SiC₂-based coating, with TSC carbosilicide (Ti₃SiC₂) 0] plane reflexes, lamellar layered structure, and reduced porosity.