Abstract The objects of the investigation are the powder of 12Kh18N10T stainless steel of the 20–63 μm powder and experimental samples formed based on it by selective laser melting (SLM). The powder was fabricated by argon atomization at a temperature of 1640°C and pressure of 27 bar. The particle structure is dendritic–cellular, and the cellular structure prevails with a decrease in the particle size

Abstract MgO is extensively used for various applications. A Venturi jet reactor can help prepare the micro- or nano-sized magnesia via pyrolysis. However, the reactors have an uneven mixing and concentration distribution. The operational and structural parameters of the reactor have therefore been optimized to overcome this issue. The numerical simulations indicate that higher flow rates of MgCl2

Abstract The results of a comparative research into the corrosion resistance of an aluminum matrix composite material produced by the oxygen lancing of a prehydrogenated aluminum alloy melt based on Al–Si–Fe with an iron content of over 1.0% and Al–7% Si alloy with an iron content of up to 0.3% modified by ligature 5Al–Ti for 2% are shown. The aluminum-alloy corrosion was conditioned by the film discontinuity

Abstract This article is devoted to the formation of amorphous coatings on the steel 35 surface by electrospark treatment in a mixture of crystalline granules. It is revealed by the energy dispersive X-ray spectroscopy (EDS) that formed coatings contain W, Mo, Co, and Ni in various ratios. The weight of granules of various compositions decreases by 11–16 wt % for 6-h treatment due to electric erosion

Abstract The main tasks of treating a melt of brass are analyzed. A comparison of traditional treatment methods with the proposed method of improving the quality of the alloy is presented. The equilibrium conditions for the decomposition reactions of carbonates are considered when treating the melt in an open and closed ladle. The conditions for the reaction of carbonate decomposition are formulated

Abstract The enormous demand for and consumption of nickel in industrial applications has induced the depletion of high-grade nickel sulfide ore, which has inevitably led to the utilization of the substantial deposits of depreciated low-grade nickel-copper sulfide ore. In this work, the mineral phase transformation and sulfation kinetics of nickel, copper, iron, and magnesium in the roasting process

Abstract The research results of the production of long deformed semi-fabricated products by sheet rolling and direct extrolling from aluminum-magnesium alloys with various scandium content are presented. Computer simulation and physical modeling methods are used and the results are verified by pilot testing. The choice of these materials as objects of research is due to the fact that aluminum alloys

Abstract Limonitic and saprolitic laterite ores are used to produce Ni by employing different kinds of processes. Acid leaching is an energy-saving process for pure Ni metal production. The high concentration of Fe in atmospheric acid leaching solution caused difficulties in metal-ions separation. In this work, saprolitic laterite ore was leached by atmospheric acid leaching solution of limonitic laterite

Abstract A cast material based on the Nb2AlC MAX phase is formed by SHS metallurgy. The synthesis is performed using the Nb2O5–Al–C mixture with the CaO2–Al high-energy additive. The results of thermodynamic calculations correlate with the experimental data. The substantial influence of the CaO2–Al additive on the thermodynamic parameters and phase composition of the product is established. It is shown

Abstract A mechanism is proposed for the joint reduction of oxides from multicomponent copper-smelting slag when they are blown with CO–CO2 gas mixtures and an algorithm is developed for its implementation in the form of a mathematical model. The first feature of the proposed mechanism is that the total rate of the overall reduction process is determined by CO consumption in the course of its interaction

Abstract This paper presents an investigation of the effects of aging temperature on the microstructure and shear strength of SAC0307-0.1Ni/Cu solder joints. Single-overlap shear solder joints were aged for 1 h at 80, 130, and 180°C. The microstructure of the interface between the solder and the Cu substrate contained phase of the intermetallic compounds (IMCs) (Cu,Ni)6Sn5 formed along the interface

Abstract A new nonstationary three-dimensional mathematical model of an aluminum reduction cell which makes it possible to perform coupled thermoelectric and magneto-hydrodynamic calculation while taking into account sideledge formation is presented. The model takes into account the nonlinear dependence of the coefficients of electrical conductivity and thermal conductivity of materials on temperature

Abstract Studies have been conducted to establish the patterns of sulfuric acid dissolution of metal sulfides in the presence of environmentally friendly oxidizing agents, ozone and iron(III) ions; determine the parameters and modes of intensified extraction of metals into solution; reduce the consumption of oxidizing agents; and develop the least environmentally intense and most cost-effective methods

Abstract The application of the agricultural waste of cashew nut shells (CNSs) from the Ivory Coast is proposed for the production of activated carbon (AC) used in water treatment by the physical activation. Washed and crushed CNSs are carbonized at 800°C. The crushed CNS carbonizate is activated by the physical method in a temperature range from 400 to 700°C. The specific surface (SBET) and porous

Abstract This paper investigated the oxidation of fayalite (Fe2SiO4) in iron-rich nickel slag (INS) for iron recycling via an oxidation-magnetic separation method. A phase stability diagram of the FeO–SiO2–MgO–CaO–O2 system drawn by FactSage 7.1 illustrates that magnetite (Fe3O4) can be crystallized from liquid slag in an air atmosphere, but the further oxidation to Fe2O3 in molten slag was extremely

Abstract The influence of different methods of producing alloys of the Fe–Cu system from immiscible components is studied. Alloys with limited solubility (LS) in liquid and solid states are impossible to fabricate by conventional metallurgy. This is why developing low-cost and simple technologies for fabricating such alloys and materials based in them, making it possible to specify the necessary level

Abstract High-purity tin is widely used in advanced technologies such as aerospace, electronic information, and nuclear industry. It has become a key material supporting the development of human science and technology innovation. However, there are few studies on the preparation methods of high purity tin. A novel technique was developed to purify 99.99682% tin by zone refining in an argon atmosphere

Abstract Experimental antifriction aluminum alloys based on an Al–5% Si–4% Cu system with the addition of low-melting components such as Bi, Pb, In, and Cd have been studied. An optimal heat treatment mode has been adjusted, including the hardening at a temperature of 500°С with further aging at 175°С. The tribological testing have been carried out according to a pad–roller scheme (Steel 45 as the

Abstract Trends and prospects for the development of industry according to materials of European and world congresses on powder metallurgy and publications in leading specialized foreign editions are analyzed. Trends of the stable development of the production of powder structural parts for the automotive industry in developed countries, including using assembly technology during joint sintering, are

Abstract The results of investigations into increasing the contrast of process properties of calcite and scheelite due to the combined application of water glass with salts such as sulfates of aluminum, zinc, iron, magnesium; mixtures of water glass and calcium chloride; sodium carboxymethyl cellulose (CMC); combinations of sodium oleate with low-polar compounds (neonol and fatty iso-alcohols); and

Abstract This work is devoted to the fabrication of ZrB2–ZrSi2–MoSi2-based composite powder ceramics by self-propagating high-temperature synthesis (SHS) according to the scheme of magnesium thermal reduction from oxide feedstock and its subsequent hot-pressing (HP) consolidation. The combustion of reaction mixtures has rather high adiabatic temperatures in a range of 2060–2120 K and burning rates

Abstract The most currently widespread method of flux-free melting of magnesium alloys is melting under a protective gas atmosphere consisting of inert carrier gas with a small additive of active gas. The ML19 (Mg–Nd–Y–Zn–Zr) casting magnesium alloy contains yttrium and neodymium; these metals are rather active. The interaction of similar alloys with protective gas atmospheres is studied poorly and

Abstract Electrolytic production, which is one of the most power-consuming and environmentally dangerous technologies, occupies a special place in nonferrous metallurgy. For example, aluminum production by the electrolysis of cryolite–alumina melts is accompanied by atmospheric emissions of fluorine-containing substances, sulfur-containing substances, and hydrocarbons, while magnesium production is

Abstract The phase and structural transformations of a powder hard magnetic alloy of the Fe–30% Cr–27% Co–1% Si–0.07% B system with a metastable α1 + α2 phase composition, elevated cobalt content, and high level of magnetic properties are studied. The density and variation coefficient of the concentration of main elements of sintered billets at a level of deformable analogs are attained by sintering

Abstract The dynamic behavior (formation/dissolution) of the ledge, depending on the electrolyte overheating temperature, thermal resistance of the lining material, and composite of the cryolite–alumina electrolyte, is studied experimentally using a model installation mimicking the actual conditions of the electrolytic aluminum production. A window that enabled the change of the lining material is

Abstract Sorption of scandium by activated carbons of VSK, DAS, and PFT brands of different origin (coconut shell, anthracite, and thermosetting-plastic waste, respectively) from sulfuric–chloride solutions (pH 2) simulating the composition of solutions for the underground leaching of complex ores is studied in batch conditions. It is established that the sorption of scandium by carbons of DAS and

Abstract New methods to monitor metal burning in D16 and V95 aluminum alloys based on using energy-dispersive X-ray spectral analysis (EDS analysis) are shown. It is known that the reduced properties of aluminum-based materials are often associated with the presence of metal burning in the structure. The structural changes caused by metal burning (partial melting of eutectics and excessive low-melting

Abstract Diffusion and homogenization in “iron (5 μm–nickel (5 μm or 50 nm)” powder systems of various degrees of dispersion during sintering (900 and 1000°C), as well as spark plasma sintering, are investigated using the Matano–Boltzmann method. Calculated diffusivities in pairs of micron powders sintering without applying pressure (900°C, 6 h) and by the spark plasma method (900°C, 5 min) in these

Abstract Powders based on the ZrO2–7 wt % Y2O3 system, into which oxides of rare-earth elements (REE)—La, Nd, and Pr—were introduced in the form of the concentrate in an amount from 5 to 15 wt %, are prepared by chemical coprecipitation from inorganic precursors. It is established that an increase in the concentrate content leads to a shift in the temperature maxima of thermal effects into the range

Abstract Powders of the KhN60M alloy (EP367, 06Kh15N60M1) are investigated. An overview of manufacturing methods of products of the KhN60M alloy is presented with the analysis of their advantages and disadvantages. It is shown that, when compared with the casting technology and hot pressing of powders of high-alloyed special steels and alloys, additive technologies enable fabricating complexly shaped

Abstract This mini review is devoted to analysis of the latest advances in the development of aluminum-based composite materials (CMs) reinforced by microstructures and nanostructures. The fabrication methods of CMs, various reinforcing additives (Al2O3, AlN, SiC, CuO, B4C, Li3N, C, and BN), and their morphological types (nanotubes, nanoplates, microparticles, and nanoparticles), as well as the structure

Abstract Binary alloys of niobium with tin, lead, and cadmium are fabricated by the deposition of nanosized metal particles atomized in low-pressure plasma using the thermal-fluctuation melting effect. This effect implies the residence of a small particle in a quasi-liquid state to a certain critical size which, if is exceeded due to vapor condensation or merging (coalescence) with other quasi-liquid

Abstract A method for determining the Faraday current efficiency (CeF) based on the ratio of partial winning currents of metal and hydrogen is considered. To calculate the magnitude of CeF based on polarization measurements, it is necessary to know the working current density and potential (Ei), at which metal deposits in the corresponding solution, as well as the kinetic parameters of hydrogen evolution

Abstract When studying nanoceramics, it is necessary to constantly keep in mind the closest interrelation of their fabrication method, structure, and properties. Nanoceramic materials are used in various branches of technology as structural and functional materials. Nanoceramics are also widely used in medicine. They are harmless, stable, and have great affinity to living organisms. ZrO2-based nanoceramics

Abstract The dependence of the phase composition and parameters of a fine structure of titanium silicon carbide in powders formed by the self-propagating high-temperature synthesis on the aluminum concentration in the 5Ti/2Si/1C reaction mixture is investigated. The aluminum content is varied in a range of 0.1–0.4 mole fraction with the conservation of the total carbon content. It is established that

Abstract Coatings formed on steel 40Kh by electrospark alloying (ESA) using TiC–NiCr and TiC–NiCr–Eu2O3 electrodes are investigated. The coatings are deposited using an Alier-Metal 303 installation in argon under a normal pressure in the direct and opposite polarity modes. The structure, elemental composition, and phase composition of electrodes and coatings are investigated using X-ray phase analysis

Abstract The surface preparation is a prerequisite for ensuring the required properties of a diamond film formed by gas-phase deposition. The influence of the temperature and concentration of the CuSO4 etchant on the structural and phase compositions of the surface of hard-alloy materials is considered in this work, and the structural and phase compositions of a continuous polycrystalline diamond film