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This paper presents the design of active harmonic current compensator (AHCC) to mitigate the current harmonics generated by supply side for an induction furnace application. Induction furnaces have nonlinear and time-varying properties, resulting in harmonics and voltage/current imbalances. AHCC are high-speed compensators that enhance the performance of induction furnaces and solve power quality issues. The proposed system is designed with modified higher order sliding control (MHOSC) algorithm and extended form of reactive power theory to generate a three-phase reference compensating current. The control method examines the sliding surface parameter uncertainties in order to obtain a controlled direct current (DC) link current when using nonlinear converters. The proposed work compares the performance of proportional integral (PI) tuned sliding mode controllers with emotional tuned intelligent controllers (ETIC). The compensated current reference signal is used to provide switching pulses for AHCC. A major advantage of MHOSC is its ability to endure external disruptions and unpredicted parameter changes, which improves reference current tracking without introducing undesirable oscillations (chattering). Implementation of the proposed control algorithm is validated in MATLAB / Simulink demonstrating that the designed AHCC compensates the harmonic current to an acceptable level (total harmonic distortion of source current is 1.54%) satisfying IEEE 519-2014 standard. [ABSTRACT FROM AUTHOR]

A new method for organizing the solid-phase reduction of pellets (briquettes) using induction heating was proposed, and the physicochemical aspects of the heating and reduction processes were investigated. A thermodynamic analysis of the reactions during solid-phase reduction was carried out; the equilibrium composition of the gaseous phase in the Fe-O-C and Mn-O-C systems was determined, and the thermodynamically permissible temperature of iron oxide reduction initiation at different values of α=PCO+PCO2 were established. The results of calculating the rate of heating of coal and ore concentrate by the metallic component of the pellets (briquette) were analyzed both under condition of the flow of chemical reactions and in the absence of chemical transformation. The experiments demonstrated the fundamental possibility of heating and reducing iron oxides inside the volume of the pellet, as well as conducting both solid-phase reduction and melting of the reduced iron to obtain liquid steel under induction furnace melting conditions. [ABSTRACT FROM AUTHOR]

For over a century, induction furnaces have been used in the core of foundries for metal melting and heating. They provide high melting/heating rates with optimal efficiency. The occurrence of faults not only imposes safety risks but also reduces productivity due to unscheduled shutdowns. The problem of diagnosing faults in induction furnaces has not yet been studied, and this work is the first to propose a data-driven framework for diagnosing faults in this application. This paper presents a deep neural network framework for diagnosing electrical faults by measuring real-time electrical parameters at the supply side. Experimental and sensory measurements are collected from multiple energy analyzer devices installed in the foundry. Next, a semi-supervised learning approach, known as the local outlier factor, has been used to discriminate normal and faulty samples from each other and label the data samples. Then, a deep neural network is trained with the collected labeled samples. The performance of the developed model is compared with several state-of-the-art techniques in terms of various performance metrics. The results demonstrate the superior performance of the selected deep neural network model over other classifiers, with an average F-measure of 0.9187. Due to the black box nature of the constructed neural network, the model predictions are interpreted by Shapley additive explanations and local interpretable model-agnostic explanations. The interpretability analysis reveals that classified faults are closely linked to variations in odd voltage/current harmonics of order 3, 11, 13, and 17, highlighting the critical impact of these parameters on the model's prediction. [ABSTRACT FROM AUTHOR]

A conventional coil configuration of electromagnetic levitation melting (ELM) systems consists of a main coil connected with an anti-loop coil to provide the stability of the levitating workpiece. The reversed current in the anti-loop coil produces a reversed magnetic field that depreciates the total magnetic flux at the workpiece. In many cases, a smaller reversed current is sufficient to provide stabilization for a levitating workpiece. This paper proposes a mutually coupled stabilization coil in place of the anti-loop coil to improve the performance of ELM systems. The proposed stabilization coil system consists of two coils, an isolated upper coil, and a main levitation coil. The two coils are galvanically isolated while magnetically linked. The upper coil current is adjustable through the distance between the coils. This allows the upper coil to operate at a lower current than the main coil current but sufficient for the workpiece stabilization. Simulation results have confirmed that the magnetic flux density at the workpiece is higher in the isolation configuration than in the conventional anti-loop configuration. Experimental results have shown that the proposed system can improve the ELM system performance by reducing the heating time and power consumption of the melting process.

Investigation of the possibility of obtaining an oxide-dispersed strengthening steel alloy based on 5 different ways of fine-dispersed strengthening particles Y2O3 injection into the liquid phase of steel Fe-13Cr (wt. %) in a vacuum. For this purpose, were conducted 5 series of experiments with different conditions and regimes. 2 series of 5 melts were carried out to evaluate the possibility of mechanical injection of yttrium oxide in the melt with different entry conditions. 3 series of 5 melts were conducted to evaluate the possibility of oxidation of metallic yttrium in the melt with the formation of yttrium oxide particles. Either melt residence or residual pressure in the furnace chamber was varied in different series. The results of ingot analysis on XRF, ICP-AES, and EDS showed that significant amounts of yttrium oxide were not injected. The method with oxidation of metallic yttrium in the melt from the reduction of specially added iron oxide with a concentration of 0.0552 ppm showed the best result. [ABSTRACT FROM AUTHOR]

Duplex stainless steel is a unique material for cast products, the use of which is possible in various fields. With the same chemical composition, melting, casting and heat treatment technology, pitting and crevice corrosion were observed at the interphase boundaries of non-metallic inclusions and the steel matrix. To increase the cleanliness of steel, it is necessary to carefully select the technology for deoxidizing with titanium or aluminum, as the most common deoxidizers, and the technology for modifying with rare earth metals. In this work, a comprehensive analysis of the thermodynamic data in the literature on the behavior of oxides and sulfides in this highly alloyed system under consideration was performed. Based on this analysis, a thermodynamic model was developed to describe their behavior in liquid and solidified duplex stainless steels. The critical concentrations at which the existence of certain phases is possible during the deoxidation of DSS with titanium, aluminum and modification by rare earth metals, including the simultaneous contribution of lanthanum and cerium, was determined. Experimental ingots were produced, the cleanliness of experimental steels was assessed, and the key metric parameters of non-metallic inclusions were described. In steels deoxidized using titanium, clusters of inclusions with a diameter of 84 microns with a volume fraction of 0.066% were formed, the volume fraction of which was decreased to 0.01% with the subsequent addition of aluminum. The clusters completely disappeared when REMs were added. The reason for this behavior of inclusions was interpreted using thermodynamic modeling and explained by the difference in temperature at which specific types of NMIs begin to form. A comparison of experimental and calculated results showed that the proposed model adequately describes the process of formation of non-metallic inclusions in the steel under consideration and can be used for the development of industrial technology. [ABSTRACT FROM AUTHOR]

The zone of stable immiscibility of liquid phases during the smelting of a copper alloy with 20% wt. Fe is obtained by using steel with 0.2% C; the research method is agree with the features of the state diagrams of Cu-Fe and Cu-Fe-C systems in the zone of low concentrations of C. In the induction crucible furnace, primary melting of steel is carried out with gradual saturation of the melt with copper with small solid additives in insignificant overheating of the melt above the liquidus temperature (up to 25 K) and laminar motion of metal. This ensures its constant presence in the state of pre-stratification (emulsion nucleuses that continuously nucleate and dissolve), which is characteristic of Cu-Fe melts. In the melt layers that surround the copper additives during their dissolution, the Cu content increases and they enter into the immiscibility zone of the Cu-Fe system alloyed with C. There spontaneous emulsification and acquisition of a stable structure by dispersed phases took place. During their subsequent transition to the mixing zone, the inherited constancy of the structure restrains the dissolution process of globularized formations. The cooling of the metal liquid is accompanied by competition between the processes of globularization and dendrites' formation. This manifests itself in the sizes of the melt volumes, which are characterized by the predominance of one of the types of phases or their parity depending on the temperature, concentration and time conditions, as well as the features of their nucleation and development. In the structure of the sheet obtained by casting in a roll crystallizer (cooling rate of ≅ 1000 K/s), 19 types of globularized formations (0.2-250 μm) are found, three of which (0.2-1.0 μm) are frozen microemulsions. Prospective directions for the application of sheet products made of copper-steel alloys with a microemulsified structure (manufacture of products by additive technologies for responsible equipment, shields from electromagnetic and thermal influences, and inserts in sliding bearings) are determined. [ABSTRACT FROM AUTHOR]

Coreless induction furnace is one of the most widely used equipment in the steelmaking sector, while the lining refractory are the key factors in determining the lifetime of the induction furnace. The multi-physics field dominates the operating conditions of the lining refractory which can be well-studied using numerical simulation techniques. Based on the technique, and adopted frequency domain-transient method, the thermal-electromagnetic flow coupled multi-physical fields is simulated and the effects of multi-physical fields on the furnace lining refractory are analyzed as well, which provides a numerical simulation guiding approach for the design of the lining refractory of induction furnace. The results indicate that the excitation magnetic field distribution dominates the multi-physics field distribution, and shows a concentrated field distribution at the bottom corner and slag line, the inner wall of the furnace lining is influenced by the liquid steel impact, the temperature, velocity and stress at the bottom corner, reach 2046 K, 0.127 m/s and 2.34 × 102 MPa respectively. With regards to the simulation results, the service conditions of these two regions and the furnace waist lining should be focused on when designing refractory for induction furnace lining. [ABSTRACT FROM AUTHOR]

The results of numerical studies of an induction-melting furnace with a cone-shaped cold crucible for vitrification of high-level wastes with noble metals are presented. The study has been carried out using a 2D electrohydrodynamic two-frequency model taking into account the movement of noble-metal particles in a borosilicate-glass melt. Based on the mathematical modeling, a furnace with an induction-drain unit that ensures complete removal of noble metals together with the drained glass melt has been developed. The directions for further numerical and experimental studies are presented. [ABSTRACT FROM AUTHOR]

First of all, the smelting equipment is the most important component of a foundry's main production process and therefore requires constant reproduction. This is ensured by timely and high-quality maintenance and repair, the cost of which is 8–12% of the total costs. The technical and economic conditions of the enterprise itself depend on this, as the productivity of workers during production is directly related to the technical condition of the equipment and its downtime for repairs. An important factor in ensuring a melting furnace's reproduction is a replacement of the worn lining, which leads to downtime of the smelting furnace and reduces the efficiency of its operation. The amount of torque required depends directly on the compound used. The quality of the manufacturing and sintering process of the lining, which provides the necessary durability, is affected by the heat capacity of the materials used when they are affected by the melting temperature of the alloys. In the present work, using the BRUKER D8 ADVANCE diffractometer, the Shimadzu XRF-1800 spectrometer and the STA 449 F1 Jupiter synchronous thermal analyzer, we probed the changes in the heat capacity of quartzite and PKMVI-3 under the action of temperatures of 200–1550 °C. This technology allows the manufacture of a lining that maintains high stability during operations at 1550–1600 °C melting modes. [ABSTRACT FROM AUTHOR]

• Removal process of iron oxides in solid waste by induction heating is investigated. • Multi-physics real-time coupling model is employed for dimensional analysis. • Reduction degree and power consumption are correlated to the dimensionless numbers. • The reduction degree is no longer increased when Re is greater than three. • The reduction degree decreases sharply when the inner diameter is larger than 8 cm. In the iron removal process by melting reduction of aluminosilicate solid waste, induction heating furnace can provide the heat source for fast melting solid wastes and carbothermal reduction, and drive the melt flow by electromagnetic force, which enhances the heat and mass transfer and improves the reduction and separation efficiency of the iron oxide impurities in the melt. In this work, based on the multi-physics real-time coupling model that integrates carbothermal reduction and interfacial mass transfer between two-phase melts in the induction furnace, several dimensionless numbers are derived by dimensional analysis of the magnetohydrodynamic equations and governing equations of physical fields, i.e., magnetic Reynolds number (Re m), Reynolds number (Re), Prandtl number (Pr), Hartmann number (Ha), Froude number (Fr), Weber number (We) and Peclet number (Pe). Combined with the physical significance of these dimensionless numbers, the constraints between different parameters and physical fields were analyzed, as well as the influences of dimensionless numbers on the two evaluation indexes of reduction degree and energy consumption. The correlation models between the dimensionless numbers and the reduction degree of iron oxides were obtained by data regression. Since the dimensionless numbers in the correlation models coupled the synergistic influences of multiple parameters on the transport processes, it can not only provide theoretical guidance for the inverse selection of design or operating parameters, but also greatly improve the applicability of the model. [ABSTRACT FROM AUTHOR]

Sulphur in steel is an undesirable element because it lowers all technological and uses values of steel products. During the steelmaking process, the desulphurization process depends on the thermodynamic conditions, the used desulphurizes, and the stability of the formed sulphides. The desulphurization technology in the production of low-carbon steel in a protective atmosphere, with the addition of synthetic slag and strong desulphurizing agents with additional argon blowing, is presented in this paper. The reduction of sulphur content achieved in the induction furnace is an important contribution to the technology of the production of low-carbon steels.

This article is a review of current scientific problems in the field of automation of the electromagnetic levitation melting process control of non-ferrous metals and potential solutions using modern digital technologies. The article describes the technological process of electromagnetic levitation melting as a method of obtaining ultrapure metals and the main problems of the automation of this process taking into account domestic and international experience. Promising approaches to control the position of the melt in the inductor in real time on the basis of vision systems are considered. The main problems and factors preventing the mass introduction of levitation melting in the electromagnetic field to the industry are highlighted. The problem of passing the Curie point by the heated billet and the effect of the billet's loss of magnetism on the vibrational circuit of the installation and the temperature of the inductor are also considered. The article also reflects key areas of research development in the field of levitation melting, including: optimization of energy costs, stabilization of the position of the melt in the inductor, predictive process control, and scaling of levitation melting units. The concept of a digital twin based on a numerical model as a component of an automatic process control system for the implementation of inductor control and prediction of process parameters of the melt is presented. The possibility of using vision for visual control of the melt position in the inductor based on video images for its further stabilization in the inductor and increasing the accuracy of numerical simulation results by specifying the real geometry of the melt in parallel with the calculation of the model itself is considered. [ABSTRACT FROM AUTHOR]

In a number of advanced materials processing applications, including float zone refining of electronic materials, forming of metallic glasses and induction melting of light alloys, oscillatory and non-oscillatory electromagnetic forces associated with the processing application are found to enhance surface shape, nucleation of precipitates, evolution of crystal nucleation sites, segregation of alloy components, grain refinement and degassing [1]-[3]. For cases where the material being processed is containerized and where the time dependence is oscillatory, these forces give rise to acoustic waves which carry energy to the boundaries of the containerized volume leading to a reduction in process efficacy should the container not present the proper acoustic impedance. This paper considers acoustic energy exchange between the molten alloy and the crucible of an induction furnace and the attendant impact on degassing. [ABSTRACT FROM AUTHOR]

The main purpose of industrial frequency induction crucible smelters (IGM) is the smelting of synthetic cast iron, using metal filling scrap in the amount of 30–35%, at a temperature not exceeding 1450 OZ C. The basis of the lining used is quartzite, which undergoes polymorphic transformations in the pre-treatment process to form tridimite. The efficiency of using these furnaces is significantly increased when using a metal casting consisting of a single steel scrap, but for this purpose, the melting mode has to be raised to 1550–1600 °C, which will reduce the resistance of the lining. The structural transformation of quartzite is strongly influenced by the state of water in it. In this work, studies have been carried out for changes in the water condition in the quartzite of the brand PCMVI-3 under the action of temperatures of 200–1550 °C. The Shimadzu XRF-1800 spectrometer established the actual chemical composition of the investigated quartzite and found that the amount of impurities in it is 0.66%. A derivative study of STA 449 F1 Jupiter found two endothermic effects. The first, at 170 °C, relates to the loss of adsorbed water. The second, at a temperature of 570 °C, passes without the loss of mass of the sample, and it is accompanied by the beginning of the process of the destruction of point defects in the form of Al-OH groupings. From a temperature of 620–630 °C, no mass changes associated with water removal were detected. The BRUKER D8 ADVANCE diffractometer investigated phase changes during the removal of moisture from the quartzite at temperatures of 200 and 800 °C and subsequent cooling and then during the heating used to sinter the lining. As a result, it has been established that the sheet in which the quartzite contains only chemically bound moisture, after sintering, turns into cristobalite and provides a more stable exposure to sudden temperature changes. This makes it possible to use up to 90% of the steel scrap in metal filling, which increases the efficiency of the melting furnace and the production of castings in general. [ABSTRACT FROM AUTHOR]

Currently, steel production through induction furnace is nearly 30% of the total steel production in the world. However, steel produced through induction furnace routes contains high sulphur (0.06 to 0.1 wt %) which is not acceptable for the structural steels. Therefore, it is imperative to develop the synthetic slag for the desulphurisation of the steel in the induction furnace. The slag properties such as sulphide capacity, sulphur partition ratio, viscosity, liquidus temperature, the solubility of components, basicity are considered to design synthetic slag for desulphurisation of the steel in the induction furnace. Developed synthetic slag is consisted of 20–30 wt% SiO2, 5–20 wt% Al2O3, 40–60 wt% CaO, 5–10 wt% MgO. The evaluation of synthetic slag is performed in the induction furnace for desulphurisation of plain carbon and alloy steel. The maximum degree of desulphurisation is 84% with the addition of 2–3 wt% synthetic slag for Al killed steel while 32% for non-killed steel is achieved. The desulphurisation time to achieve the sulphur level (0.03–0.04) is 10 minutes using developed synthetic slag (2–3 wt% liquid metal). Sulphur partition and sulphide capacity of synthetic slag increase with the basicity of the developed synthetic slag. [ABSTRACT FROM AUTHOR]

Recent years have seen an increase in interest in steelmaking from scrap because it has the potential to lessen the environmental effect of steelmaking as a recycling process. This study provides the comprehensive assessment of the environmental impacts of steel produced in facilities utilizing electric arc furnace (EAF) and induction furnace (IF) technology. Since there has not been any previous research comparing these effects of these two steelmaking processes, which use scrap as a raw material, this study used the LCA approach to analyze the environmental impacts. A local Turkish steelmaking facility for IF provided the necessary inventory data. Compared to EAF in the rest of the world (4.75x105), steel produced by IF has a better overall single score result (3x105), and IF also emits 7.3% fewer CO2-equivalent (GHG) emissions while using 21.8% less water. In terms of the consumption of mineral and fossil resources and the impacts on global warming, steel produced with IF does have an advantage over steel produced with EAF. The source of electrical supply, along with water consumption and global warming, is responsible for the majority of environmental effects. The IF's single score drops to 2.63x105 when European electricity supplies are used in its substitute. This demonstrates that lowering CO2 emissions during the production of electricity is essential for lowering the carbon footprint of steel products and numerous other goods that include steel in their supply chains. [ABSTRACT FROM AUTHOR]

The development of boron nitride (BN) aerogels with excellent performance, including low density, excellent mechanical properties, superior chemical inertness, and oxidation resistance, is of great significance for their practical applications, especially in harsh environments. However, the main challenge for the large-scale preparation of nanostructured BN aerogels is to simultaneously obtain BN units with high purity and crystallinity, while maintaining their nanostructure characteristics. Herein, we have creatively prepared high-quality BN aerogels by high-temperature pyrolysis of a melamine diborate (M·2B) aerogel precursor via induction heating. The synthesized BN aerogels consist of one-dimensional porous BN microfibers. Induction-derived pyrolysis with a rapid heating rate and an ultrahigh temperature can greatly reduce the growth time of BN nanocrystals, resulting in the maintenance of the purity, crystallinity, and nanostructure feature of BN fiber units simultaneously. As the pyrolysis voltage increases, the thermal stability and oxidation resistance of the BN aerogel have been greatly improved, and its resistivity has increased by at least three orders of magnitude, mainly due to its low carbon and oxygen impurity content and high crystallinity. The as-prepared BN aerogels exhibit excellent comprehensive properties, including superb thermal stability and oxidation resistance, as well as excellent mechanical properties and thermal insulation. Therefore, BN aerogels can find promising applications in energy storage, catalysis, and environmental remediation, especially in harsh working environments. [ABSTRACT FROM AUTHOR]

First of all, the smelting equipment is the most important component of a foundry’s main production process and therefore requires constant reproduction. This is ensured by timely and high-quality maintenance and repair, the cost of which is 8–12% of the total costs. The technical and economic conditions of the enterprise itself depend on this, as the productivity of workers during production is directly related to the technical condition of the equipment and its downtime for repairs. An important factor in ensuring a melting furnace’s reproduction is a replacement of the worn lining, which leads to downtime of the smelting furnace and reduces the efficiency of its operation. The amount of torque required depends directly on the compound used. The quality of the manufacturing and sintering process of the lining, which provides the necessary durability, is affected by the heat capacity of the materials used when they are affected by the melting temperature of the alloys. In the present work, using the BRUKER D8 ADVANCE diffractometer, the Shimadzu XRF-1800 spectrometer and the STA 449 F1 Jupiter synchronous thermal analyzer, we probed the changes in the heat capacity of quartzite and PKMVI-3 under the action of temperatures of 200–1550 °C. This technology allows the manufacture of a lining that maintains high stability during operations at 1550–1600 °C melting modes.

Rapid formation of the MAB phase ceramic, Mn2AlB2, by the method of induction furnace-assisted self-propagating high-temperature synthesis (SHS) was investigated in this work. The effects of Al content, high-energy ball-milling and cold pressing load on phase purity and reaction behaviour were also examined. An Al content of 140% allowed the highest conversion of reactants to Mn2AlB2. Increasing ball-milling time was shown to increase phase purity and reduce SHS ignition and peak temperatures. Unpressed powder samples exhibited higher phase purities and significantly lower SHS ignition temperatures than pressed samples. It was revealed that Mn2AlB2 forms by a two-stage reaction in this process, as evidenced by the presence of two exothermic peaks in the temperature-time data. The short synthesis times and equipment scalability available using this method offer a unique solution for the large-scale fabrication of MAB phase powders.

This article is a review of current scientific problems in the field of automation of the electromagnetic levitation melting process control of non-ferrous metals and potential solutions using modern digital technologies. The article describes the technological process of electromagnetic levitation melting as a method of obtaining ultrapure metals and the main problems of the automation of this process taking into account domestic and international experience. Promising approaches to control the position of the melt in the inductor in real time on the basis of vision systems are considered. The main problems and factors preventing the mass introduction of levitation melting in the electromagnetic field to the industry are highlighted. The problem of passing the Curie point by the heated billet and the effect of the billet’s loss of magnetism on the vibrational circuit of the installation and the temperature of the inductor are also considered. The article also reflects key areas of research development in the field of levitation melting, including: optimization of energy costs, stabilization of the position of the melt in the inductor, predictive process control, and scaling of levitation melting units. The concept of a digital twin based on a numerical model as a component of an automatic process control system for the implementation of inductor control and prediction of process parameters of the melt is presented. The possibility of using vision for visual control of the melt position in the inductor based on video images for its further stabilization in the inductor and increasing the accuracy of numerical simulation results by specifying the real geometry of the melt in parallel with the calculation of the model itself is considered.

The main purpose of industrial frequency induction crucible smelters (IGM) is the smelting of synthetic cast iron, using metal filling scrap in the amount of 30–35%, at a temperature not exceeding 1450 OZ C. The basis of the lining used is quartzite, which undergoes polymorphic transformations in the pre-treatment process to form tridimite. The efficiency of using these furnaces is significantly increased when using a metal casting consisting of a single steel scrap, but for this purpose, the melting mode has to be raised to 1550–1600 °C, which will reduce the resistance of the lining. The structural transformation of quartzite is strongly influenced by the state of water in it. In this work, studies have been carried out for changes in the water condition in the quartzite of the brand PCMVI-3 under the action of temperatures of 200–1550 °C. The Shimadzu XRF-1800 spectrometer established the actual chemical composition of the investigated quartzite and found that the amount of impurities in it is 0.66%. A derivative study of STA 449 F1 Jupiter found two endothermic effects. The first, at 170 °C, relates to the loss of adsorbed water. The second, at a temperature of 570 °C, passes without the loss of mass of the sample, and it is accompanied by the beginning of the process of the destruction of point defects in the form of Al-OH groupings. From a temperature of 620–630 °C, no mass changes associated with water removal were detected. The BRUKER D8 ADVANCE diffractometer investigated phase changes during the removal of moisture from the quartzite at temperatures of 200 and 800 °C and subsequent cooling and then during the heating used to sinter the lining. As a result, it has been established that the sheet in which the quartzite contains only chemically bound moisture, after sintering, turns into cristobalite and provides a more stable exposure to sudden temperature changes. This makes it possible to use up to 90% of the steel scrap in metal filling, which increases the efficiency of the melting furnace and the production of castings in general.

In this present work the influence of austempering heat treatment was studied on ductile iron. Medium frequency induction furnace was used to make casting samples. Austempered Ductile Iron (ADI), which is a relatively new material is produced by the process of austempering heat treatment. ADI material is a very valuable. The properties of ADI are equivalent to forged steel. This study was done to develop Austempered Ductile Iron and to find out the effect of heat treatment temperature. In this study samples were treated, one with higher heat treatment temperature i.e. 370 0C and other in lower range of temperature i.e. 285 oC were used. For austenitizing of samples the furnace temperature was maintained at 900 oC and the samples were heated for one hour. After austenitizing, the samples were dipped in a salt bath at temperatures i.e. 285 oC and 370 oC for one hour. The researcher found encouraging result. Almost double tensile strength was achieved with the same composition of the samples only with the heat treatment at lower temperature.

The specialized literature describes engineering analytical methods for the design of induction furnaces. The design procedures described in this documentation contain a large volume of information (theoretical and experimental) that is particularly useful for the design engineer, in the form of tables, formulas, and diagrams. The paper aims to present a solution for the optimization of the design parameters of an inductive furnace for aluminum melting.

Data are provided for preparing fuzed and fuzed stabilized zirconia from baddeleyite and synthetic zirconia in induction, plasma, and electric arc furnaces. Results are discussed and prospects for carbothermal preparation of zirconium dioxide from zircon in an electric arc furnace are demonstrated. A favorable effect of oxidation melting in an electric arc furnace on quality and the process of fuzed product preparation is demonstrated. Data are provided for preparing fuzed zirconia from zircon in plasma furnaces. [ABSTRACT FROM AUTHOR]

Product quality is a major concern in manufacturing. In the metal processing industry, low-quality products must be remanufactured, which requires additional labor, money, and time. Therefore, user-controllable variables for machines and raw material compositions are key factors for ensuring product quality. In this study, we propose a method for generating the time-series working patterns of the control variables for metal-melting induction furnaces and continuous casting machines, thus improving product quality by aiding machine operators. We used an auxiliary classifier generative adversarial network (AC-GAN) model to generate time-series working patterns of two processes depending on product type and additional material data. To check accuracy, the difference between the generated time-series data of the model and the ground truth data was calculated. Specifically, the proposed model results were compared with those of other deep learning models: multilayer perceptron (MLP), convolutional neural network (CNN), long short-term memory (LSTM), and gated recurrent unit (GRU). It was demonstrated that the proposed model outperformed the other deep learning models. Moreover, the proposed method generated different time-series data for different inputs, whereas the other deep learning models generated the same time-series data.

Increasing electronic waste (e‐waste) volume from the electronic industry and households has been creating primary health and environmental considerations because some of the e‐waste materials contain toxic substances. This study mainly focuses on the recovery of metals from e‐waste based on the melting temperatures of recyclable metals and centrifugal forces, thereby reducing the environmental pollution and recovering valuable metals for future use in the same or different industries. A perforated basket was designed and manufactured from stainless steel for feeding the chopped e‐waste. An induction furnace attached to a perforated basket was used to melt solder, aluminum, and other metals of the e‐waste. Around 95% of all metals was recovered from the e‐waste at different rotations (400–700 rpm) and temperatures (100–1,200°C) in less than a minute. The economic analysis indicated that this process was highly profitable and affordable for the future investment in the field. This study will also open new possibilities of extracting other metals from e‐waste by induction heats and centrifugal forces in affordable and fast manners for sustainable use of the electronic materials in the same or different industries. [ABSTRACT FROM AUTHOR]

The structurization and phase composition of reaction-sintered silicon carbide (RSSC) modified by chromium carbide are examined. When hexagonal silicon carbide is used, the modification of RSSC by chromium carbide stabilizes the cubic lattice of secondary silicon carbide. A solid solution of silicon in chromium carbide is formed when the samples are impregnated with liquid silicon. In the impregnation of porous samples, silicon influences the consolidation of chromium carbide particles because they are displaced by liquid silicon. Depending on the particle size and features of starting silicon carbide, RSSC is characterized by various structural modifications. A hexagonal 6H structure shows up in RSSC produced from the nanosized cubic solid solution of carbon in silicon carbide. [ABSTRACT FROM AUTHOR]

The properties and wear resistance of induction furnace linings made from Karelian vein quartz during the smelting of copper-based alloys are studied. The wear mechanism of a vein quartz lining is demonstrated. [ABSTRACT FROM AUTHOR]

The characteristics of superfine powder composites formed in the interaction of nanosized silicon carbide with iron oxide in vacuum and argon at 1200 and 1400°C, respectively, are analyzed. Silicon carbide (β-SiC), iron silicide and carbide, silicon oxide, and silicon oxynitride are main components of the powder composites. The lattice parameter of SiC in the powder composites synthesized in the SiC–Fe2O3 system is determined. In the interaction in the SiC–Fe2O3 powder mixture in vacuum, secondary SiC is synthesized with a lattice parameter that corresponds to the standard parameter for cubic β-SiC. The interaction in an argon atmosphere is accompanied by the synthesis of secondary SiC with a decreased lattice parameter. The minimum lattice parameter (0.4336 nm) is 0.6% smaller than the standard parameter for cubic β-SiC. The morphology of the powder composite synthesized in the SiC–Fe2O3 system is studied. The average particle size of the powder composite decreases with increasing weight content of secondary SiC. [ABSTRACT FROM AUTHOR]

In order to achieve energy and climate goals, energy and resource efficiency are considered a key measure. Limit-value-oriented methods such as the exergy analysis and the physical optimum method are used to show the limits of efficiency improvement. In this context, the physical optimum represents the theoretical ideal reference process. Despite their similarities, no comprehensive comparison to the exergy analysis has been carried out yet. Thus, the purpose of this study is to close this gap by examining differences and intersections using the example of an induction furnace. The minimum energy input according to the physical optimum method is 1327 MJ/t whereas the exergy of the melting product is 1393 MJ/t, depending on transit flows taken into account. The exergy analysis extends considerably beyond the physical optimum method in terms of the complexity and accuracy of the assessment of material flows by using exergy units. The exergy analysis makes clear which exergy is linked to the losses and thus reveals the potential for coupling processes. This results in different areas of application for the two methods.

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Large amounts of solar-grade silicon were wasted as silicon powder waste (SPW) during the diamond-wire saw slicing process. In this paper, the SPW was purified by acid leaching, and the purified SPW was pelletized. Then the pellets were melted in induction furnace in air atmosphere to produce high-purity silicon ingots. Firstly, the SPW as raw material was characterized. The results show that the particle size of the powder is mainly in the range of 0.14∼8.71 μm, the powder has a shape of thin flake, the contents of SPW are Si 83.99 wt%, silicon oxide 13.5 wt%, others 2.51 wt%, of which B (boron) 0.2 ppmw, P (phosphorus) 4.32 ppmw, and metallic impurities 16412 ppmw, respectively. Secondly, the SPW was purified by acid leaching and the leaching parameters were optimized, i.e. leaching time 80 min, temperature 60°, acid concentration 25%, liquid-solid ratio 10 mL/g and agitation speed 200 rpm. Thirdly, the purified SPW was pelletized and then melted in induction furnace in air atmosphere. High-purity silicon ingots with Si 99.99%, B 0.16 ppmw and P 1.1 ppmw were produced. The slag mainly consists of 48.63 wt% Si, 43.51 wt% SiO2 and 7.86 wt% SiC. The high-purity silicon ingots can be used to produce aluminum silicon alloy and silicon nitride. And it is prospective to use the high-purity silicon ingots as the feedstock to produce solar grade silicon (SoG-Si). [ABSTRACT FROM AUTHOR]

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[Display omitted] • Migration of microparticle impurities in the uranium melt inside an induction furnace. • Homogeneous distribution of smaller carbide microparticles (less than50 μm) is predicted. • Larger particles (>50 μm) tend to move toward the crucible wall and upward in the system. • Particle shape does not have a significant impact on particle distribution in the melt. Understanding and controlling impurity behavior in actinide metal casting processes are foundational for efficient part production yet remain major challenges for researchers and industry. To help provide insight regarding impurity distribution during actinide metal casting, we have developed computational fluid dynamics (CFD) models for a laboratory-scale system using commercial and open-source codes. This article describes multiple experiment-informed models designed to simulate a specific laboratory system in which uranium melt, containing a known starting concentration of carbon impurity, is electromagnetically stirred in an induction furnace. The goal of the simulations is to predict the motion of impurity particles in the form of uranium monocarbide in the velocity field of the melt. Prior to simulating the uranium–carbon system, numerical models were validated using a previously published nonradioactive experimental system. Effects of the size and shape of impurity particles in the models were investigated and agree with experimental findings. Simulation of smaller particles (less than 50 μm) shows more homogenous distribution throughout the stirred melt. With increased particle size (100 μm), the body forces, which include the buoyancy force, dominate over the drag force, causing larger particles to move toward the crucible walls and upward in the system. [ABSTRACT FROM AUTHOR]