Metallurgical Research Articles

ИННОВАЦИОННЫЕ ИНСТРУМЕНТЫ УПРАВЛЕНИЯ ФИНАНСОВОЙ УСТОЙЧИВОСТЬЮ ОРГАНИЗАЦИЙ И ЭФФЕКТИВНОСТЬ ИХ ПРИМЕНЕНИЯ

in this article, the authors consider innovative tools for managing the financial stability of commercial organizations. The definition of financial stability is given, its role in ensuring the financial security of the enterprise is determined. The key ways and methods of assessing the financial stability of an enterprise are being studied. The possibilities of using innovative tools for managing the financial stability of commercial organizations are analyzed and their possible effectiveness for implementation at enterprises of the metallurgical industry is determined.

On the Issue of Environmental Safety in the Metallurgical Industry

On the Issue of Environmental Safety in the Metallurgical Industry

Effectiveness of silicomanganese smelting utilizing high-ash coal

This study investigates the utilization of high-ash coal as an alternative reductant in the smelting of silicomanganese, aiming to reduce the carbon footprint of traditional coke-based processes. Experiments were conducted using an ore-thermal furnace with a transformer power of 200 kVA to simulate industrial conditions. The charge consisted of manganese ore (Mn - 36%), slag from refined ferromanganese production (MnO - 25%), and high-ash coal (ash content 40%–50%). Chemical analysis of the produced alloy showed a composition of Mn–70%, Si–20%, C–1.28%, P–0.06%, and S–0.05%, meeting the standards for silicomanganese. The results demonstrate that high-ash coal can replace coke without compromising the quality of the alloy. This approach not only indirect CO2 emissions but also leverages the abundant availability of high-ash coal, which is often discarded as waste. The study highlights the potential for significant environmental benefits and cost savings, making this method a viable alternative for sustainable industrial practices. The findings support the industrial application of high-ash coal in silicomanganese production, contributing to more eco-friendly and economically feasible metallurgical processes.

Statistical and geospatial assessment of trace and toxic elements distribution in ground and surface water of northern parts of the Indo-Gangetic plains: Source identification and health risk assessment

This study focusses on ground and surface water resources in the northern parts of the Indo-Gangetic Plains. The study aims to identify potential contaminants, analyse their distribution, trace their origins, and evaluate associated health risk. Samples from 80 locations; groundwater (n = 69) and surface water (n = 11) were analysed for nineteen trace and toxic elements using ICP-MS. Eight elements in groundwater (Mn, Fe, Ni, Zn, As, Tl, U and Se) and six in surface water (Al, Mn, Fe, Ni, Zn, and Tl) exceeded WHO (2011) and BIS (2012) limits in certain areas. The geospatial analysis reveals hotspots of trace and toxic element concentration, with higher levels detected in the southeast and western regions of the study area. Correlation matrices revealed a robust correlation (∼>0.75–0.99, p < 0.01) among all trace and toxic elements (excluding Li, Be, As, Ag, and U) in surface water samples when compared to groundwater samples. Cluster analysis and principal component analysis (PCA) (explains 70.09 cumulative percent for total 6 of factors) of groundwater chemistry indicates that Zn, Ni and Tl contamination may originate from industrial activities (metallurgical processes and manufacturing). The potential sources of Mn may be both geological and human-induced, while Fe, Se, As and U can originate from specific geological formations or human-related activities like over-extraction and leaching of excess fertilizers into aquifers. For surface water, PCA (explains 92.92 cumulative percent for total 5 of factors) identifies industrial activities as the main source of Mn, Fe, Tl, Ni, and Zn, while Al originates from both geological and anthropogenic sources. The water quality index indicated poor to very poor water quality in the western and central regions, whereas the northern and eastern regions exhibited excellent water quality. Health risk assessment reveals HI values for groundwater water: 3.85 (adults), 7.70 (children); surface water: 1.52 (adults), 3.05 (children), emphasizing the urgent need for remediation measures.

Моделирование гидродинамики жидкого металла в ячейке МГД-сепаратора

Ensuring the purity of metals and alloys is a key problem in both the metallurgical and nuclear industries. The difference in the electrical conductivity of the molten metal and impurity particles allows their separation from each other in a non-contact way using an electromagnetic force. In addition to the implementation of phase separation, such force inevitably sets the liquid metal in motion, changing the velocity distribution in the separation cells. This effect is most pronounced in channels of rectangular geometry and therefore should be studied extensively. In this paper, we numerically study the hydrodynamics in a separation cell in the presence of partitions of various configurations and in the presence or absence of an external weighting electromagnetic force with the aim to determine the cell geometry providing the most efficient separation and accumulation of impurity particles in it during the cyclic pumping of liquid metal. It has been found that the intense force action leads to the occurrence of parasitic vortices in the channel, which reduce the efficiency of the separation process. The initial flow velocity does not practically affect the topology of the flow in the channel, whereas the height and configuration of the baffles inside the channel, together with the magnitude of the external weighting force have a significant effect on the flow of liquid metal. It is shown that in the zones between the baffles, the parasitic vortices that could potentially facilitate the washout of impurity from this space are not formed. Based on the results of numerical study the optimum configuration of the MHD-separator cell is selected. It corresponds to the mode with the most effective separation according to four parameters: partition height, magnitude of the external weighting electromagnetic force, flow velocity, and topology of intermediate partitions.

Optimization of process parameters for selective chlorination and volatilization in FeO-Cu2O-CaCl2 system

Selective chlorination and volatilization is an effective approach for element separation in non-ferrous metallurgical processes, and has also been used for the separation of iron oxide and copper oxide within steel industry. In this work, to determine and optimize the conditions for copper and iron separation in FeO-Cu2O-CaCl2 system, a series of orthogonal experiments were carried out to investigate the effects of reaction temperature, holding time, mole ratio of CaCl2 to Cu2O (n(CaCl2)/n(Cu2O)), and gas flow rate on the separation efficiency. Results demonstrated that both reaction temperature and n(CaCl2)/n(Cu2O) take significant effects on the final copper volatilization ratio. In contrast, the gas flow rate and holding time shows a negligible influence on the effect of separation between copper and iron. By increasing the reaction temperature and n(CaCl2)/n(Cu2O), the copper volatilization ratio significantly increases, while the iron volatilization ratio remains at a low level. When the reaction temperature was 1273 K, the holding time was 90 min, n(CaCl2)/n(Cu2O) was 2.0, and the gas flow rate was 100 mL·min−1, the copper volatilization ratio reached 51.08 % and the iron volatilization ratio was only 6.52 %. The chlorination reaction rate of copper was controlled by chemical reaction and the apparent activation energyEa was 57.17 kJ/mol.

Water and Energy Conservation across Provinces and Sectors in China: Based on a Complex Network Perspective

Previous studies on the water–energy nexus mainly focused on the calculation and comparison of resource consumption at the national or regional level, lacking interprovincial sector-sector transfer analysis. In this study, the intensity of water and energy consumption of various sectors in China was calculated, the key nodes and paths of resource networks were identified, and countermeasures for resource conservation were proposed from the new perspective of the “dual saving” and “bidirectional saving” of water and energy. The results showed that the metallurgical industry (Me) in Jiangsu and the chemical industry (Ch) in Hebei and Jiangsu had high node strength in the water and energy network and were key sectors in China with “dual saving” effects of water and energy. The construction industry, Ch, Me in Jiangsu, electricity and hot water production and supply industry in Beijing, and Me in Hebei had high node strength in the water-related energy network and energy-related water network, significantly supporting the “bidirectional saving” effect of water and energy in China. The electrical equipment industry (El) in Jiangsu → El in Zhejiang, El in Zhejiang → El in Shanghai frequently appeared in key paths, which could effectively reduce the resource consumption of the entire network.

Optimal Control of the Dynamics of Physical and Chemical Processes of Blending and Melting of Copper Concentrates

This paper presents the developed model of dynamics of the physicochemical processes of electromelting of copper concentrates, which was obtained taking into account the available a priori information, which makes allowance for the main features of an object and describes the change of the basic variables of the process state (quantitative aspects of material flows and power, the composition of charge, matte, and slag). Such a model can be used in the field of automation of technological processes in metallurgical and mechanical engineering, and manufacturing. Due to the complexities of the technological process, it was advisable to use classical methods.

Minimizing Porosity in 17-4 PH Stainless Steel Compacts in a Modified Powder Metallurgical Process

Nowadays, powder-based manufacturing processes are recognized as cost-efficient methods frequently employed for producing parts with intricate shapes and tight tolerances in large quantities. However, like any manufacturing method, powder-based technologies also have several disadvantages. One of the most significant issues lies in the degree of porosity. By modifying the morphology of the gas-atomized spherical 17-4PH stainless steel powder via prior ball milling and then raising both the pressure of cold compaction (1.6 GPa) and sintering temperature (1275 °C), the porosity could be reduced considerably. In our novel powder metallurgical (PM) experimental process, an exceptionally high green density of 92% could be reached by employing die wall lubrication instead of internal lubrication and utilizing induction heating for rapid sintering. After sintering (at temperatures of 1200, 1250, and 1275 °C), the samples aged in the H900 condition were then mechanically tested (Charpy impact, HV hardness, and tensile tests) as a function of porosity. Sintering at 1275 °C for one hour enabled porosity reduction to below 4%, resulting in 1200 MPa yield strength and 1350 MPa ultimate tensile strength with significant (16%) fracture strain. These values are comparable to those of the same alloy products fabricated via ingot metallurgy (IM) or additive manufacturing (AM).

Influence of nickel plating on the welding metallurgical mechanism, microstructure, and shear performance of C101/80Au20Sn/C101 solder joints

Herein, electroplated and electroless plating processes were used to plate nickel (Ni) on the surface of C101 alloy, which is a low-carbon steel with a carbon content of approximately 0.1% and Fe primarily contributing to the rest of the content and which is commonly used in metal packaging, and electroplated Ni and electroless Ni C101/80Au20Sn/C101 solder joints were prepared. The welding metallurgical mechanisms, microstructures, and shear performances of the two types of solder joints were investigated through experimental observation, material characterization, shear testing, and finite-element analysis (FEA). The diffusion of Ni atoms within the two platings was evaluated using first-principles calculation. Results indicated that the atomic arrangement of the electroplated Ni layer was polycrystalline, whereas that of the electroless Ni layer was primarily amorphous. The orientation of Ni grains in the electroplated-Ni joints affected the growth of (Ni,Au)3Sn2 throughout the welding metallurgical process. The [111] orientation suppressed the growth of (Ni,Au)3Sn2, resulting in a discontinuous distribution of (Ni,Au)3Sn2 at the Ni/solder interface and considerable variations in the thickness of (Ni,Au)3Sn2. Amorphous Ni in the electroless Ni layer promoted the growth of (Ni,Au)3Sn2, resulting in a continuous (Ni,Au)3Sn2 layer having a relatively uniform thickness. The shear strength of the electroplated-Ni joints was considerably lower than that of the electroless-Ni joints. FEA results demonstrated that the locations of stress concentration in the electroplated- and electroless-Ni joints were at the (Ni,Au)3Sn2/solder interface and within the solder matrix, respectively. First-principles calculations showed that the diffusion performance of Ni atoms in the electroless Ni layer was considerably superior to that of Ni atoms in the electroplated Ni layer.

The Influence of Slide Burnishing on the Technological Quality of X2CrNiMo17-12-2 Steel.

Metal products for the metallurgical and machinery industries must meet high requirements in terms of their performance, including reliability, accuracy, durability and fatigue strength. It is also important that materials commonly used to manufacture such products must meet specific requirements. Therefore, various techniques and technologies for modifying the surface layer are becoming more and more widely used. These include burnishing, which may be dynamic or static. This article studies the process of slide burnishing of surfaces of cylindrical objects. The burnishing was performed using a slide burnisher with a rigid diamond-tipped clamp on a general-purpose lathe. The tests were performed for corrosion-resistant steel X2CrNiMo17-12-2. The aim of the research was to determine the impact of changes in burnishing conditions and parameters-feed rate, burnisher depth and burnishing force at a constant burnishing speed-on the surface roughness and hardness. Additionally, the microstructure was assessed in the critical areas: the surface and the core. Another phenomenon observed was surface cracking, which would be destructive due to the occurrence of indentation. In the paper, it was stated that the microstructure, or rather the grains, in the area of the surface layer was oriented in the direction of deformation. It was also observed that in the area of the surface layer, no cracks or other flaws were revealed. Therefore, slide burnishing not only reduces the surface roughness but hardens the surface layer of the burnished material.

New Certified Reference Material of Tungsten Concentrate for Developing Multielement Analysis Techniques

A new multielement certified reference material of tungsten concentrate (GSO 11541–2020) – wolframitehubnerite concentrate (hard-alloyed), KVG(T) was developed. Its metrological characteristics were established via results of interlaboratory experiment. The analytical results were obtained at the testing laboratories of 13 scientific and manufacturing organizations of Russia, Belarus, Kazakhstan, and Uzbekistan using single-element chemical analysis methods (gravimetric, spectrophotometry, atomic absorption spectrometry, etc.), as well as modern multielement methods (atomic emission spectrometry with arc discharge or inductively coupled plasma, inductively coupled plasma mass spectrometry, X-ray fluorescence spectrometry). The mass fraction values for ten elements certified; for eleven elements recommended; and for 39 elements, as well as hygroscopic and crystallization water, are given as information data. This CRM is intended for certification and validation of single and multielement methods, as well as quality assurance in analysis of the ores and products of their processing in mining, metallurgical, and chemical industries and in scientific research. The information potential of GSO 11541–2020 is higher than that of imported reference materials.

Enhancing point cloud data fusion through 2D thermal infrared camera and 2D lidar scanning

Sensor data fusion from multiple sources plays a pivotal role in advancing our understanding of real-world phenomena. This paper focuses on the integration of a thermal imager and a lidar to simultaneously capture four-dimensional (XYZT) space coordinates and temperatures. The fusion of data relies on establishing correspondence between overlapping lines in the lidar’s 3D point cloud and the infrared (IR) camera’s 2D thermal map. The presented combination method offers several key advantages. Firstly, it simplifies the calibration process. Furthermore, it can achieve near real-time performance, enabling prompt data analysis. Moreover, the method demonstrates high accuracy in capturing spatial information and temperature measurements. The thermal IR camera used in the experiment features a 1280 × 1024 pixel cooled indium antimonide (InSb) detector, operating in the short wavelength infrared (MWIR) spectral range of 1.5 to 5.5 µm. It provides temperature readings with ± 1 K accuracy and sub-30 mK resolution. On the other hand, the lidar system delivers centimeter-level precision within a range of approximately 1 to 12 m, even in well-lit outdoor environments. The experimental results validate the effectiveness of our combined system, successfully generating high-quality four-dimensional (4D) point clouds. The integration of the thermal IR camera and profilometer presents an intriguing tool with significant potential in various industrial applications. For instance, it can be employed to accurately assess gas leaks, enhance metallurgical processes, and improve safety on construction sites.

Copper Alloying Improves the Microbiologically Influenced Corrosion Resistance of Pipeline Steel

Microbiologically influenced corrosion (MIC) has long been a critical issue due to its potential to cause severe damage to equipment and the associated risk of operational failures, leading to significant financial losses. This study investigates the resistance to MIC caused by sulfate-reducing bacteria (SRB) in four types of pipeline steel materials, which are soon to be introduced to the market. Two of these materials have been alloyed with copper during the metallurgical process. The uniform corrosion rates of the copper-alloyed materials were found to be 0.012 ± 0.002 mm/y, 0.060 ± 0.01 mm/y, and 0.010 ± 0.001 mm/y under test conditions of 25 °C, 40 °C, and 60 °C, respectively. In contrast, the unalloyed steels exhibited corrosion rates of 0.370 ± 0.033 mm/y, 0.060 ± 0.01 mm/y, and 0.378 ± 0.032 mm/y, respectively. The data indicate that the copper-alloyed materials demonstrate superior resistance to MIC, as confirmed by corrosion morphology, weight loss measurements, and electrochemical data. These findings suggest that copper alloying can significantly enhance the MIC resistance of steel materials, offering a promising direction for future material development.

The road to carbon neutrality in the metallurgical industry: Hydrogen metallurgy processes represented by hydrogen-rich coke oven gas, short-process metallurgy of scrap and low-carbon policy

Abstract With the acceleration of global industrialization, the concentration of carbon dioxide is increasing in the atmosphere, and its negative impacts have seriously affected all walks of human life, so achieving carbon neutrality has become an urgent task for achieving sustainable development. As an important energy-intensive industry, the metallurgical industry occupies an important position in the global carbon-neutral agenda. In China, the metallurgical industry is actively researching and developing a new green metallurgical model of “replacing carbon with hydrogen”, exploring the feasibility of utilizing renewable energy sources to produce hydrogen from electrolysis to reduce iron ore, and at the same time utilizing hydrogen-rich coke oven gas to get rid of the over-reliance on coke; at the same time, the government’s policies provide support and incentives to elevate sustainable development and technological innovation in the metallurgical industry. support and incentives to elevate sustainable development and technological innovation in the metallurgical industry. Against this background, this paper describes the key initiatives taken by the metallurgical industry in the process of achieving carbon neutrality, including the metallurgy using hydrogen processes using hydrogen-rich coke oven gas as a source of reducing gas, short-process metallurgy of scrap, and technology that reduce emissions and save energy. Through case studies and policy analyses of new green metallurgy, this study demonstrates the potential and achievements of the metallurgical industry in achieving global carbon neutrality. It concludes with a call for the metallurgical industry to continue to strengthen innovation and work with governments and academia to pave the way toward carbon neutrality. Through new metallurgical technologies, improved energy and resource efficiency, and sustainable development, the metallurgical industry will make a significant contribution to the goal of global carbon neutrality.

Computational Fluid Dynamics Modeling of Multiphase Flows in a Side-Blown Furnace: Effects of Air Injection and Nozzle Submerged Depth

The side-blown smelting process is becoming popular in the modern metallurgical industry due to its large potential for dealing with complex materials. To further enhance its efficiency, it is essential to comprehensively understand the complex gas–liquid flow behavior in the smelting bath. In this study, the volume-of-fluid method is employed to establish computational fluid dynamics modeling on a 1:5 scaled model of a side-blown furnace. The simulation was validated against the experimental results. Notably, the influences of the nozzle’s submerged depth, injection velocity, and angle were systematically investigated. The results show that increasing the injection velocity from 29.44 to 58.88 m/s resulted in 52.97%, 116.67%, 500.00%, and 5.88% increases in the interface area, liquid velocity, liquid turbulent kinetic energy, and gas penetration depth, respectively. The maximum gas–liquid interface area, gas penetration depth, velocity, and turbulence of the liquid were found at an injection angle of 30°. Furthermore, increasing the submerged depth increased the interface area and the velocity of the liquid but decreased the turbulent kinetic energy of the liquid. Overall, increasing the injection velocity is considered a more effective measure to strengthen the smelting intensity.

Numerical study on the effect of high efficient cooling nozzles and varying cooling intensity on metallurgical transport behaviors during the slab continuous casting

In this study, the spray characteristics of the cooling water flux of the traditional single nozzle and novel dual nozzle were innovatively and effectively incorporated into a 3D/2D flow-temperature-concentration segmented model. The model was used to investigate the effects of spray characteristics on the flow, heat distribution, solute transport, solidified shell, and mushy zone of steel in the continuous casting. The results showed that various flow patterns of liquid steel in the turbulent zone significantly affected the temperature and carbon concentration distribution. Until Zone 7, the cooling water fluxes in the six cases remained unchanged. The peak temperatures of cases 1 and 4 in Zone 7 were 1253.11 and 1273.51 K, respectively, indicating that the spray characteristic was the primary cause of the variations in slab surface temperatures. The cooling water fluxes in the six cases change from Zone 8 onward. The six cases had differences of −21.39, 17.87, 46.95, −22.08, 16.86, and 45.68 K between the initial and final temperatures in Zone 8, respectively, meeting the requirement of keeping the maximum temperature recovery rate of slab surface under 100 °C/m. However, the final temperatures for cases 2, 3, and 6 were 1225.62, 1196.50, and 1218.91 K, respectively. These temperatures fall within a realistic plastic temperature range, which must be higher than 1220 K. As a result, the plastic cracking in the slab was possible. The maximum temperature gradient differences of the six cases between feature lines at the end of Zone 8 were 0.793, 0.814, 0.829, 0.185, 0.179, and 0.179 K/mm. These results showed that the optimization effect on the temperature gradient difference was insignificant as the cooling intensity rose. However, the carbon concentration uniformity was marginally improved by increasing the cooling water flux. Finally, a state-owned steel company in China chose case 5 (dual nozzle with moderate cooling intensity at the slab solidified end) as the optimum option for the slab continuous casting caster. The dual nozzle enhanced and promoted the efficient and homogeneous production of the metallurgical process.

A clean metallurgical process for vanadium precipitation from vanadium-rich solutions

Ammonium salt vanadium precipitation process has excellent performance in industrial production, but its shortcomings such as high cost and environmental impact are not conducive to sustainable development. In this paper, ethylenediamine was selected as the precipitant, and vanadate was precipitated from acidic simulated vanadium-rich solutions by the ammonium salt precipitation process. The high purity V2O5 product was obtained after calcination. Under optimal conditions, the precipitation rate of vanadium reached 94.8 %, and the purity of vanadium was as high as 99.1 %. The vanadium precipitation product was hexamethyl ammonium, and the vanadium product was V2O5. It can be derived by the differential method that the reaction order was n = 2.4, the reaction rate equation was CV-1.4=kt+a, and the apparent activation energy was 27.8097 kJ/mol, which can be classified as the diffusion-controlled reaction. This innovative process enables a savings of 5050 yuan per ton of V2O5. On this basis, a complete V2O5 production process with zero waste discharge was designed.

The effect of NaOH and KOH on the strength-mechanical properties of alkali-activated composites based on granulated blast-furnace slag

Abstract Alkali-activated systems are a more sustainable alternative to Portland cement concrete. The activation of latently hydraulic and pozzolanic raw materials in these composites is one of the many investigated factors, where the price ratio and the ability to optimally activate the mentioned precursors with the given activator play a major role. The subject of the presented work is a comparison of the influence of NaOH and KOH on the development of the strength-mechanical properties of alkali-activated materials based on granulated blast furnace slag - the secondary raw material of metallurgical processes.

ВАРИАНТ КОМПАКТИРОВАНИЯ МЕЛКОДИСПЕРСНЫХ ЖЕЛЕЗОСОДЕРЖАЩИХ МАТЕРИАЛОВ ДЛЯ МЕТАЛЛУРГИЧЕСКОГО ПЕРЕДЕЛА

The paper presents the results of a study of options for compacting fine iron-containing materials for metallurgical processing. The authors have proposed a method that involves the use of, in addition to an iron-containing material, a thermoplastic binder material. In this case, aggregation of the mixture and strengthening of the resulting aggregates is carried out simultaneously in a closed mold under the influence of pressure and temperature not lower than the softening temperature of the thermoplastic material. It is possible to obtain a compact unit, convenient for storage and transportation, that successfully performs the functions of a charge component during cupola and blast furnace melting of cast iron.