Aluminum master alloys with rare earth metals are widely studied by many scientists around the world, but research on the production of Al-Er master alloys is still limited. The purpose of this work is to study the microstructure parameters of aluminum-erbium master alloys obtained by metallothermic reduction of salt mixtures containing erbium oxide or fluoride. The structural features were investigated by optical and scanning electron microscopy, and the dependence of the microhardness of the eutectic and solid solution fields of obtained master alloys on the content of erbium in the master alloy was determined. Studies have shown that master alloys obtained by metallothermic reduction of erbium compounds from chloride–fluoride melts are characterized by a uniform distribution of Al₃Er intermetallic compounds in the volume of double eutectic [(Al) + Al₃Er] and have a strong grain refinement effect. The analysis of the microstructure showed that the structure of the master alloys varies depending on the content of erbium. When the content of erbium in the master alloy is up to 6 wt.%, the eutectic structure is preserved. When the content of erbium in the master alloy is 8 wt.% or more, the structure becomes a solid solution with individual inclusions of various shapes and intermetallic compounds.

Iron and steel industry is one of the industrial branches making substantial input in provision of economic growth in Russian Federation; in this connection, innovation development of the metallurgical industry is rather important. The patent researches, in their turn, allow to get statistical data about the patents that are indicators of technological development and reliable parameter of innovation activity in the industry. The paper is devoted to study of the tendencies of innovation development of the national vertically integrated mining and metallurgical companies in order to reveal technological and innovation leaders and trends in this industry. The paper uses the patent method of technological prediction based on patent researches. The results of analysis of patent documents for the large metallurgical companies (Severstal, Magnitogorsk Iron and Steel Works (MMK), Novolipetsk Iron and Steel Works (NLMK), Metalloinvest Management Company, EVRAZ Group, Mechel) are presented. The rating of Russian patentee companies — leaders in iron and steel industry — is prepared for the period 2000-2020. The legal status of patent documents included in the patent portfolios of the companies is determined. Patent activity of the companies is analyzed during the examined period with differentiation by years. The patent documents registered in Russia during 20 years, as well as the documents of Nippon Steel and JFE Holdings are also analyzed for comparison. The collection for each patentee was obtained and their interest areas (corresponding to the definite classes of International Patent Classification (IPC)) were examined with revealing of the most important IPC subgroups. Activity of authors of the examined companies is investigated in order to find out the leading technological development specialists.

The article is devoted to the research into the process of the triple magnesium-zinc-gadolinium master alloys synthesis. As a result of thermal analysis, the temperature intervals of thermal effects during the process of gadolinium recovery from its fluoride in the melt of KCl – NaCl – СaCl2 salts with magnesium and zinc were established. As a consequence of a series of experiments, the main regularities of the magnesium-zinc-gadolinium master alloy synthesis from the selected technological salt mixture were recognized, and the main factors of the metallothermic process affecting the degree of gadolinium recovery were also determined. It is experimentally proved that during the triple Mg – Zn – Gd master alloy synthesis, the rational magnesium to zinc ratio, which reduces the synthesis temperature and synthesis time of triple master alloys when reducing gadolinium from the technological KCl – NaCl – СaCl2 – GdF3 salt mixture, is 1:2. The magnesium-thermal reduction process on zinc addition is characterized by the high extraction level of gadolinium (up to 99.2%). The microstructure analysis has showed that a uniform distribution of intermetallic compounds (Mg3GdZn6) in the magnesium-zinc double eutectic volume distinguishes the resulting 25Mg – 50Zn – 25Gd triple master alloys. The authors express their gratitude to V. L. Ugolkov, Candidate of Technical Sciences, Senior Researcher of the Nanostructure Research Laboratory of the Institute of Silicate Chemistry of Russian Academy of Sciences, for assistance in conducting thermal analysis.

Production of metallurgical silicon for Al – Si alloys and silumins is of strategic importance and defines the future of a great number of Russian industries. Reducing the weight of commercial silica, which belongs to the expenditure side of the balance, is the key resource-saving objective of the silicon industry. In today’s environment, it is necessary to develop a monitoring and control system for quartz burden used for the production of metallurgical silicon as it would help tackle the issues caused by the reliance on different sources of raw materials, which can differ in terms of impurities content. This can affect the energy performance of the smelter and the quality of the final product. At the basis of the proposed system there lie mathematical calculations and models built with an account for the physicochemical and polymorphous transformations of the quartz material during smelting in an ore-thermal furnace. The paper relies on the relationships obtained earlier that show how the amount of microsilica and the type of emissions are determined by the chemical composition and the size distribution, the structure of quartz material and the smelting temperature. A CFD model of the exhaust duct of the furnace was used to obtain new data on dust and gas emissions. As a result, an algorithm was built that help analyze how the quality of the mineral material influences the amount and the type of emissions generated by silicon industry. The authors implemented a central data acquisition and analysis module that links the chemical composition with the size distribution of three samples of the quartz material while coordinating them with the key smelting parameters (i.e. speed, exhaust gas pressure, electric mode). The material balance monitoring and control software, which accounts for impurities as elements and compounds, as well as transition and phase states of silica at all process stages, enables to control the output of waste in the form of microsilica of required structure in order to process it and obtain high value-added materials. The proposed balance monitoring and control scheme will help raise the process efficiency by 15–20%.

In the presented article, a differential thermal analysis was carried out and the temperatures of thermal effects were established that arise during the reduction of neodymium from a technological salt mixture KCl–NaCl–CaCl₂–NdF₃ with a magnesium–zinc alloy. The results of experimental studies on the reduction of neodymium from a fluoride–chloride melt in a shaft electric furnace at temperatures of 550, 600, 650, 700 °C are presented. In order to increase the degree of extraction of neodymium into the Mg–Zn–Nd master alloy, the study of the influence of technological parameters on the degree of extraction of neodymium was carried out. It was experimentally proven that when zinc is added to a reducing agent (magnesium), the degree of extraction of neodymium into the master alloy is 99.5–99.7%. The structure of the obtained master alloy samples, characterized by a uniform distribution of ternary intermetallic compounds (Mg_3,4NdZn₇) in the volume of a double magnesium–zinc eutectic, was studied by optical and electron microscopy.

This work investigates the synthesis process and characterization of a novel type of aluminum-ytterbium master alloy in molten salts. The significance of the obtained results for the research conducted in the field so far is due to the previously proven effectiveness of the influence of ytterbium on the structure and properties of aluminum alloys. During experimental work, the thermodynamic analysis of the aluminothermic process of ytterbium fluoride reduction from molten salts was performed and revealed that the process might occur and develop in the presence of sodium fluoride and potassium chloride if the NaYbF4 precursor is formed. Subsequently, the temperature intervals of thermal effects during the process of reduction of ytterbium from its fluoride in molten salts (NaF – KCl) by aluminum were determined as a result of thermal analysis. During Al – Yb master alloys synthesis experiments, the maximal value of ytterbium extraction to master alloy of 82.5% was achieved by changing the process parameters, such as temperature, reaction time, and molten salts/aluminium ratios. Besides, master alloys containing ytterbium from 1.1 to 5.1 wt.% were synthesized using the optimized technological process conditions and examined with metallographic analysis. The analysis revealed that the microstructure of the synthesized master alloys is presented by eutectic colonies of Al + Al3Yb composition located along the boundaries of α-Al dendritic cells. It was found that about 85.5% of the area of the studied samples with ytterbium content of 5.1 wt.% consist of aluminum dendrites with an average cell size of 25 μm. The presented in this research results are of significant importance for the development of cheap and high-quality aluminum alloys.