INDUCTION HEATING-BASED CARBOTHERMIC FERROBOR-BASED ALLOY POWDER PRODUCTION METHOD

Abstract

The invention relates to an induction heating-based production method for the production of ferroboron-based alloy powder. In this method, solid raw materials containing iron, boron, and carbon are subjected to a solid-phase carbothermic reduction reaction under controlled heating conditions using an induction heating system. This ensures efficient and controlled heating in the reaction zone, resulting in the direct production of ferroboron-based alloy powder containing FeB and Fe₂B phases. This method offers an alternative to conventional furnace methods, enabling the production of a more homogeneous product, shortening reaction times, and eliminating the need for additional crushing, grinding, or mechanical size reduction processes.

Description

1 TARIFF INDUCTION HEATING-BASED CARBOTHERMIC FERROBOR-BASED ALLOY POWDER PRODUCTION METHOD Technical Area 5 The invention involves the production of ferroboron-based alloy powder from raw materials containing iron and boron. The invention relates to a carbothermic production method based on induction heating. In the field of metallurgy and powder metallurgy, process technologies for ferroalloy production. It is related to. State of the Art Ferroboron is composed primarily of iron and boron elements, and is particularly... A main component used to facilitate the addition of boron in iron and steel metallurgy. It is an alloy. Ferrobor is not a single chemical compound with a stable stoichiometric structure. The boron content varies depending on the raw materials used and production conditions, resulting in 15 types such as FeB and Fe₂B. It is a multiphase ferroalloy system that can contain different iron boride phases. Commercial ferroboron The products mostly contain approximately 10-20% boron by weight, the remaining The component is mainly composed of iron and, depending on the production method, may also contain carbon, silicon, It consists of aluminum and similar impurities. Ferroboron its microstructure mainly consists of iron diboride (Fe₂B) and iron boride (FeB) phases, along with boron 20 iron-rich α-iron (α-Fe) phase in compositions with low iron content They can be found in FeB and Fe₂B phases, exhibiting high hardness, wear resistance, and thermal properties. It demonstrates stability. However, this is especially true in contrast to the high hardness of the FeB phase. It also has high brittleness. Therefore, ferroboron is generally hard, brittle, and mechanically unsound. It is a malleable alloy. The density and melting behavior of the alloy are 25 magnetic properties and electrical conductivity depend on the amount of boron it contains and its phase distribution. This varies depending on the situation. The most common use of ferroboron is in iron and steel production. Adding elemental boron directly to molten steel in a controlled manner is difficult. Therefore, boron is usually introduced into the steel bath via a ferroboron master alloy. It is given. Even the addition of very small amounts of boron results in the formation of 30 austenite (gamma-Fe) grains. It can increase the hardenability of steel by delaying phase transformations at its boundaries. Thus, achieving hardening in larger sections improves the efficiency of heat treatment. increasing the use of more expensive alloys such as chromium, molybdenum or nickel in certain applications. 2 It is possible to reduce the amount of its components used. Ferrobor also wear-resistant steels, tool steels, high-strength structures in steels, in the modification of cast irons and in hardfacing alloys It is used. Another important application area of ​​ferrobor is in iron-based amorphous materials. and the production of nanocrystalline magnetic materials. Boron facilitates the crystallization of the molten alloy. 5 making it more difficult to obtain an amorphous structure during rapid solidification. This facilitates the process. Therefore, ferrobor is used in transformer cores, at low costs. in core loss magnetic strips, soft magnetic alloys and various electrical- Iron-silicon-boron (Fe-Si-B) or similar boron compounds used in electronic applications. It is considered as a boron source in the preparation of alloys containing 10. The main aluminothermic and carbothermic methods in the commercial production of ferroboron are used. It is used. In the aluminothermic method, raw materials containing boron oxide and iron oxide are used. The materials are reduced exothermically via metallic aluminum. The process In an idealized scenario, the reduction of boron and iron oxides by aluminum and This is expressed as the formation of an aluminum oxide (Al₂O₃) based slag as a byproduct. 15 This can happen. The boron released as a result of the reaction dissolves in the iron or It reacts with iron to form FeB and Fe₂B phases. The aluminothermal method has a relatively low external energy requirement and high while having advantages such as generating heat within the reaction process The presence of residual aluminum in the final product, slag inclusions, and compositional homogeneity are all factors that contribute to a problem. Problems such as control issues may arise. In the carbothermic method, boric acid... oxide, boric acid or boron minerals, iron, iron oxide and coke, charcoal or Boron is processed at high temperatures together with a similar carbonaceous reducing agent. The reduction of oxide with carbon in an idealized form is Boron trioxide + 3 carbons → 2 boron + 3 carbon monoxide (B₂O₃ + 3C → 2B + 3CO) reaction can be shown, however 25 The actual process involves reduction in the gas phase, volatility of boron oxide, and the formation of iron phase boron. multiple simultaneous processes such as dissolution within it and the formation of iron borides It involves a mechanism. In carbothermic ferroboron production, electric arc furnaces are used. immersed arc furnaces, vertical shaft furnaces and similar high-temperature systems It can be used. The resulting ferroboron is mostly obtained in the molten phase. 30 and then it is solidified. However, high energy consumption, carbon difficulties in controlling the ratio, the formation of undesirable phases such as boron carbide, boron There are process limitations such as losses and non-homogeneous reaction progress. In the electric arc furnace method, boric acid, boron oxide or boron mineral; iron oxide, metallic 3 iron, charcoal, coke, and wood chips that increase load-bearing capacity when needed. The components are mixed and fed into the oven. Between electrodes or with electrodes. The electric arc created between the furnace base and the furnace floor provides the necessary high voltage for reduction and melting. It provides the required temperature. In immersed arc or arc-resistance furnaces, the electrodes... The tips enter the furnace load and heat is transferred from both the arc region around the electrode and the surrounding area. and the Joule current generated when an electric current passes through a resistive furnace charge. It is obtained from heat. Iron oxides are first reduced, then higher At these temperatures, the reduction of boron oxide takes place, and the reduced boron is liquid iron. It is held by [the system]. The resulting ferroboron melt accumulates at the bottom of the furnace, It is taken from the casting hole and poured into molds to solidify. In arc furnaces 10 High temperature inside the furnace due to heat concentration at the electrode tips Gradients can occur. Overheated areas around the electrode. while found in the furnace walls or upper parts of the load, not fully melted or Sintered materials can remain if the carbon content is high. Mass formations containing graphite phase and ferroboron occur under the electrode. 15 However, insufficient carbon content prevents the complete formation of boron oxide. This leads to its non-reducibility and a decrease in boron yield. The stability of the arc, Changes in electrode distance, charge permeability, and electrical resistance also affect temperature. This can negatively affect the homogeneity of the distribution and reaction progress. Shaft In the furnace method, boron oxide or boric acid is mixed with pre-reduced or sintered 20 The load, consisting of iron source and coke, is continuously passed through the top of a vertical furnace. or is fed in a semi-continuous manner. The solid load moves downwards. The hot reducing gases move upwards. Thus, the drying of the load is achieved. Heating and partial reduction are ensured. The temperature in the lower part of the furnace is rising, the remaining reduction reactions are being completed, and ferroboron-based metallic 25 The product is obtained. However, the volatility of boron oxides in shaft furnaces causes gas. Boron loss due to flow, changes in gas permeability within the charge, and boron the high temperature required for reduction is homogeneous throughout the entire cross-section Failure to provide this is a significant problem in some shaft furnace applications in current technology. Due to the low boron recovery rate and the amount of carbon in the resulting product, 30 It is reported that an additional decarburization process is required. Resistance type. In furnaces, heat is generated by passing current through graphite or another electrically resistant element. or it is generated by passing an electric current directly through the furnace load. These furnaces are particularly used in ferroboron production for preheating and sintering raw materials. 4 initiating metallothermal reactions, conducting solid-state reactions, or It can be used for the preparation of Fe-B alloy under a controlled atmosphere. Some industrial-scale systems operate solely on the arc principle or solely on the resistance principle. No, it is an arc-resistance type where both heating mechanisms are effective together. It is working. Resistance ovens allow for more controlled application of temperature. 5 Although it provides heat transfer, the long heat transfer time in large volume loads, both at the center and at the surface the creation of temperature differences between them and keeping the product at a high temperature for a long time It can promote grain growth. Furthermore, the traditional oven in question... In these methods, ferroboron is usually taken from the furnace in the form of molten metal and processed into ingots. It is solidified in the form of blocks or irregular masses. Therefore, it is directly thin and 10 It is not possible to obtain a ferroboron product with a controlled particle size. Large During the solidification of bulk ferroboron melt in a mold, the surface regions rapidly The inner regions, however, cool more slowly. This difference in cooling rate causes the crystals to... Nucleation and growth occur at different rates in different regions of the product. This causes it to occur. Especially long solidification at the center of the mass 15 Due to the duration of the process, large, oriented, or dendritic crystal grains may form. The distribution of iron and boron between the solid and liquid phases differs during solidification. This can lead to enrichment or depletion of boron in certain areas. As a result, iron-rich α-Fe regions and Fe₂B and FeB-rich regions The regions can be distributed irregularly within the product. Thus, ferrobor 20 variations in chemical composition throughout the ingot, microsegregation, macrosegregation, Different phase ratios and microstructural heterogeneity can occur. Mass In order for ferrobor product to be used in powder form, it must be crushed, passed through a jaw crusher, Additional mechanical processes such as grinding and sieving are required. Ferrobor Due to the hard and brittle FeB and Fe₂B phases in its composition, these processes require high energy. It can consume it. Impurities can be transferred from the grinding elements to the product, resulting in irregularities. Particles with an angular morphology can be formed. Additionally, crushing and grinding can occur. As a result, a product with a wide particle size distribution may emerge, and Numerous grinding and classification steps are required to obtain the desired fine size fraction. This stage may be required. Therefore, 30 arc, shaft or resistance-based furnaces are needed. In traditional methods, the final product is usually obtained in a dense and bulky structure. This situation necessitates additional size reduction processes, and This can lead to the formation of microstructural heterogeneity. This situation affects ferroboron. compositional repeatability, dissolution behavior in alloy bath and powder metallurgy, coatings or additive manufacturing requiring controlled particle properties It limits the performance of applications. Patent application number US4509976A, which is included in the prior art, Reduction of colemanite or other borates with aluminum or magnesium and 5 a study on the production of ferroboron by using iron as a boron collector It relates to the method. The patent application in question concerns the use of high-purity boric acid as an alternative. It allows the use of natural borates such as colemanite and is exothermic. It aims to reduce energy requirements by utilizing reduction reactions. It also allows the boron to be held by the iron, thus improving traditional smelting methods by 10 It offers detailed process conditions aimed at increasing boron recovery compared to other methods. Induction furnaces are used only for melting briquetted reaction products. It is stated as one of the pieces of equipment that can be used. The method described, It is based on aluminum or magnesium reduction and the reaction As a result, ferroboron is sintered in a calcium aluminate matrix of 15. Due to its formation, processes such as crushing, grinding, magnetic separation, and subsequent melting are used. It requires several additional processes. Therefore, directly fine-grained and homogeneous Obtaining ferroboron powder, limiting particle growth, temperature distribution precise control and elimination of long process chains It does not offer an adequate solution to these issues. 20 In current technology, heat is transferred from the external environment via reaction in arc, shaft, or resistance furnaces. Long processing times and high energy requirements in processes that rely on transferring material to the environment. consumption, non-homogeneous temperature distribution, difficulty in process control, especially arc electrode refractory wear in furnaces, boron losses, unwanted side reactions and 25 Product purity is negatively affected, as ferroboron is generally dense and bulky. obtained in this state, grain growth due to prolonged thermal exposure, disordered phase additional elements are needed to allow the product to be powdered due to its distribution and microstructural heterogeneity. problems such as the need for crushing, grinding and screening processes An improvement in the field has become necessary. 30 Brief Description and Objectives of the Invention The invention involves reducing raw materials containing iron and boron in a carbonaceous reduction medium. high required for reaction and formation of ferroboron-based alloy powder 6 The text explains how the heat is generated by an induction heating system. in the system in question, the variable electromagnetic field generated by the induction coil the field creates eddy currents in conductive materials in the reaction medium and this The principle is that currents are directly converted into heat as a result of the electrical resistance of the material. is being taken. 5 The purpose of the invention is to replace conventional ferroboron-based furnaces based on arc, shaft or resistance furnaces. As an alternative to alloy powder production methods, induction heating technology creating controlled heating conditions and efficiently managing the production process 10 a ferroboron-based alloy powder production method that allows for its management The aim is to provide this. For this purpose, powdered iron and boron containing iron and boron are used. Raw materials are subjected to a variable electromagnetic field in a carbon-based reduction environment. It is exposed to and the high temperature required for the reaction is induction heating system. It is generated through this process. Thus, heat is transferred from the furnace environment to the reaction mixture over a long distance. Instead of being transferred by temporary heat transfer, the induction field is transferred in conductive materials 15 as a result of the eddy currents it creates, directly in the reaction zone It is produced. Another objective of the invention is to achieve the high required level for the formation of ferroboron-based alloy powder. Reaching the required temperatures quickly and shortening the total production time 20 The invention provides a variable magnetic field generated by an induction coil. field, vortex within electrically conductive components in the reaction medium These currents generate the electrical currents of the material. As a result of its interaction with resistance, heat is released directly within the material. It is emerging. The rapid generation of high temperatures in the reaction zone causes iron 25 and diffusion and reaction processes between boron-containing solid raw materials It speeds up the process and reduces the need for lengthy kiln firings. Another objective of the invention is to regulate the reaction during the production of ferroboron-based alloy powder. The goal is to ensure a more homogeneous and controlled temperature distribution throughout the mixture. 30 In traditional ovens, heat transfer occurs from the surface towards the center and regionally. In contrast to temperature differences, the invention uses induction heating in the heat reaction region. It is created volumetrically. The power and frequency applied to the induction system The heating speed and the depth of the electromagnetic field can be controlled thanks to their adjustability. 7 This allows for more precise analysis of the reaction kinetics and temperature profile. It is possible to manage it in this way. Another aim of the invention is to create a coarse-grained material with irregular phase distribution and microstructural irregularities. By limiting the formation of heterogeneous ferroboron-based alloy powder products, fine 5 The aim is to produce a granular and homogeneous ferroboron-based alloy powder. In this invention... Thanks to rapid and controlled heating by induction, the reaction mixture can be heated for a long time. High temperature retention is prevented, and thermal processes that cause grain growth are avoided. Exposure is reduced. At the same time, the temperature is lowered throughout the reaction volume. regular distribution of Fe-B phases results in regionally irregular formation of the phases and composition 10 by reducing variations, a more repeatable product microstructure is obtained. It contributes. Another objective of the invention is to produce ferroboron-based alloy powder using conventional methods. not in the form of an ingot or a mass structure as it is, but 15 of the initial raw materials The invention aims to ensure that the product is obtained in powder form in relation to particle sizes. Within this scope, raw materials containing powdered iron and boron undergo carbon reduction. It is subjected to a solid-solid reaction in the environment, and the entire product is melted and poured into a mold. A production approach based on casting is not applied. Thus, high hardness The subsequent crushing, grinding and 20 of the bulk ferroboron-based alloy powder product The need for classification is reduced. The energy generated from these processes. to prevent consumption, cost, time loss and potential contamination problems It is being passed. Another aim of the invention is to reduce energy consumption, production costs, and the traditional oven 25 The aim is to contribute to reducing the environmental impacts resulting from these processes. In the production method described in the invention, energy is transferred to the reaction in the induction heating system. Thanks to its direct creation in the region where it takes place, the entire furnace is made of refractory material. high levels of the structure and surrounding areas that do not participate in the reaction for a long period of time. It is not necessary to raise the temperatures to these levels. This reduces heat losses, electrode and refractory 30 It is more economical by reducing consumption, processing time and energy requirements per unit of product. and creates a more environmentally friendly production process. 8 Another purpose of the invention is to produce ferroboron-based alloy powder using an inert or The goal is to enable the process to be carried out under controlled atmospheric conditions. The invention involves an induction heating system that provides localized and rapid heating in the reaction zone. by means of heating, inert gases or controlled reaction atmospheres It can be effectively applied directly to the reaction volume. Furthermore, invention 5 Thanks to this, it is possible to limit unwanted oxidation and side reactions. Atmosphere control can also be applied in traditional oven systems. together, due to the prolonged storage of large volume loads at high temperatures Managing the influence of the atmosphere on the reaction environment is more difficult and less effective. It can happen at the event. 10 Explanation of the Figures Figure 1: Isometric View of the Induction Furnace and Platform Figure 2: Top of the Induction Furnace Unit (after Inert Atmosphere Cabinet assembly) Its appearance is 15 Figure 3: XRD analysis of the obtained ferroboron-based alloy powder sample. Figure 4: EDS element of the obtained ferroboron-based alloy powder sample. Mapping analysis (A: SEM image, B: Map of the oxygen element, C: Boron) (map for the element D: Iron, E: Carbon) Figure 5: Heat treatment diagram showing the applied heat treatment stages. 20 Figure 6: Technical drawing view of the graphite crucible (9) Figure 7: Technical drawing view of the ceramic crucible (10). Descriptions of the Elements / Components Constituting the Invention 1. Reaction furnace unit 25 2. Induction coil 3. Power supply and control unit 4. Cooling water pump 5. Equipment cabinet 6. Left and left side viewing window 30 7. Protective cabin 8. Protective cabin door 9. Graphite crucible 10. Ceramic crucible 9 11. Computer (PC) 12. Temperature measuring device (Thermal camera / Thermocouple) Detailed Description of the Invention The invention is an induction heating-based system for the production of ferroboron-based alloy powder. It is related to a carbothermic production method. The invention concerns the production of carbothermic ferroboron-based alloy powders based on induction heating. method, i. as a boron source, ≥98% pure diboron trioxide (B₂O₃) or equivalent boric acid 10 acid (H₃BO₃), with a powder size of ≤50 μm and a purity of ≥ 99%, as a carbon source. The carbon and iron source is fine powdered iron with ≥99% purity or Using equivalent amounts of iron oxides, the amount of boron oxide is stoichiometric. raw material powder components will be 2-4% higher than the value preparation, 15 ii. A homogeneous reaction mixture of the prepared raw material powder components. to obtain, bring to the same grain size structure and between the components mechanical mixing and / or ball bearing to increase contact effectiveness homogenization by subjecting it to a grinding process, iii. The initial reaction charge of the homogenized reaction mixture is 20 used directly in powder form in the reaction mixture in a graphite crucible. (9) placement inside, or ensuring load integrity, ease of transport and / or feeding into the system. Depending on application requirements such as those mentioned above, the reaction porosity can be 25. by applying a compression pressure of ≤5 bar in a way that will protect it, into pellet form. by bringing and placing the reaction mixture into the graphite crucible (9), iv. positioning the graphite crucible (9) inside the ceramic crucible (10) and double A layered crucible system that isolates the reaction zone from environmental influences, ensuring operator safety and, if necessary, operating under an inert atmosphere for 30 minutes. in the reaction furnace unit inside the protective cabinet (7) suitable for working (1) Placement of the induction coil (2) in the center and the protective Closing the cabin door (8), v. an induction heating system operating in the 1–100 kHz frequency range of the mixture heating with, vi. Carbothermic reduction reaction by applying the temperature program by initiating and proceeding the reaction in a controlled manner, iron-boron (Fe– B) Formation of intermediate phases and iron monoboride (FeB) and iron diboride 5 Obtaining a ferroboron structure containing (Fe₂B) phases, vii. After the completion of the reaction, the product is induction coil (2) controlled cooling inside and the cooled product is graphite ferroboron based alloy obtained in the form of 2-20 μm by taking from the crucible (9). Obtaining the powder 10 It includes the steps involved in the process. The cooling water pump (4), which is included in one application of the invention, is in the induction coil. to remove the heat generated and to operate the coil at a controlled temperature. The cooling water used is in a closed circuit between the chiller and the induction system 15 It provides circulation. Cooling water pump (4) system operation dissipating the heat generated during the process and ensuring the relevant components operate at the appropriate operating temperature. It provides circulation of the coolant for the purpose of retention. The invention is one of The equipment cabinet (5) included in the application contains the required components, spare parts and It is an accessory element for storing maintenance and repair equipment and is 20 The equipment cabinet (5) is not a necessary element in terms of the technical operation of the invention. storage of system components, spare parts and maintenance / repair equipment only It is an accessory used for that purpose. In one application of the production method described in the invention, a boron source with a purity of ≥98% 25 boron oxide (B₂O₃) or boric acid (H₃BO₃) with a purity of ≥98%; as a source of iron. Iron powder (Fe) with a purity of ≥99%, Iron-III Oxide (Fe₂O₃) or Iron-II,III Oxide (Fe₃O₄); carbon powder with a purity of ≥99% is used as the carbon and reduction source. It is used. In one application of the invention, the stoichiometric amount of boron source is used. According to the data, porous boron with a purity of ≥98% will be used as a boron source, with a 4% higher purity. oxide (B₂O₃), fine iron powder with a purity of ≥99% (or equivalent) as an iron source. iron oxide) and graphite (<50 µm) with a purity of ≥99% as a carbon source It is used. The raw material mixture is passed through a ball mill (BPR) at a ratio of 10:1 for 20 minutes. It is being processed. Homogenized and particle size refined reaction. 11 The mixture is loaded into an induction heating system and heated at 900 °C for 10 minutes, then at 1200 °C for 10 minutes. A three-stage heat treatment process involving holding times of 60 minutes at 1600 °C and 60 minutes in total. The recipe is being followed. After the heat treatment is completed, the reaction crucible The product is taken from the system, cooled under ambient conditions, and remains in the crucible. is obtained. In this application of the invention, a purity of ≥95% and a median of 5 A ferroboron-based alloy powder product with a particle size d(0,5) = 9.9 µm is obtained. In one application of the invention, the raw material mixture is heated in multiple stages using induction heating. A heat treatment has been applied, and the heating program is approximately 900 °C for 10 minutes, approximately. The steps are holding at 1200 °C for 10 minutes and at approximately 1600 °C for 60 minutes. It includes temperature levels, holding times, and number of levels. This can be varied depending on the raw materials used and the product to be obtained. The heat treatment graph of the application is given in Figure 5. The reaction that occurs in this invention is shown in Reaction 1, with the reaction equation given in 15. 3𝐹𝑒 𝑂 + 𝐶𝑂 → 2𝐹𝑒 𝑂 + 𝐶𝑂 𝐹𝑒 𝑂 + 𝐶𝑂 → 3𝐹𝑒𝑂 + 𝐶𝑂 𝐹𝑒𝑂 + 𝐶 / 𝐶𝑂 → 𝐹𝑒 + 𝐶𝑂 / 𝐶𝑂 𝐵 𝑂 + 3 𝐶 → 2 𝐵 + 3 𝐶𝑂 20 𝐵 𝑂 + 3 𝐶 + 2 𝐹𝑒 → 2 𝐹𝑒𝐵 + 3 𝐶𝑂 Reaction 1. According to the reaction equation in Reaction 1, the amounts of iron, boron, and carbon are theoretically 25. The compensation for boron losses is determined based on the stoichiometric reaction. In order to support the formation of the FeB phase, the boron source is supplied in theoretical quantities. boron oxide (B₂O₃), boric acid (H₃BO₃) or to provide approximately 2–4% more. These are used as compounds providing equivalent boron. Within the scope of the invention... Iron, boron, and carbon sources in powder form suitable for solid-solid reaction 30 is being prepared. In the invention, boron oxide (B₂O₃) with a purity of ≥98% or is used as a boron source. Boric acid powder, iron powder or iron oxides with a purity of ≥99% as an iron source. Carbon powder with a purity of ≥99% (<50 µm) was used as the carbon source. However, the invention is not limited to the specified particle sizes and is also carbothermic. 12 different powder sizes to ensure the reaction takes place effectively It also includes the use of raw materials. The iron, boron and carbon to be used. The sources are reduced to particle sizes suitable for solid-solid reactions. Using raw materials in powder form after reducing them to a similar particle size, the components By increasing the contact surface area between them, the carbothermic reduction reaction can be carried out more effectively. It contributes to its realization. Specified amounts of boron, iron, and carbon. the sources, mechanical mixing in order to obtain a homogeneous reaction mixture and / or undergoes ball milling. Milling and / or mixing process conditions; type of raw materials used, physical properties and initial particle size It can be modified depending on the situation. The critical aspect of the invention is that the raw materials are 10 homogeneous mixing in accordance with the reaction and / or desired particle size This involves bringing the components into distribution within the reaction mixture. homogeneous distribution, ensuring appropriate particle size distribution, and reaction This makes it possible to create an effective contact surface during the process. The resulting Homogeneous reaction mixture, directly in powder form, depending on application conditions 15 as well as being used, alternatively to ensure the integrity, transportation and / or safety of the load. Depending on application requirements such as ease of feeding into the system, the reaction by applying low-level compression pressure in order to preserve its porous structure It is prepared in pellet form and the reaction start is introduced into the induction heating system. It is fed as a load. In one application of the invention, the homogenized reaction 20 The mixture is compressed into pellet form by applying compression pressure (≤5 bar) and It is fed into the induction heating system as an initial reaction load. Powder This form ensures a more homogeneous Fe–B distribution and higher product purity. It is preferred in terms of purity. If powder form is used, the final product purity is maintained. ≥90%, while the final product purity is 70-80% when using pellet form. 25 It is within the range. The reaction mixture is placed in a graphite crucible (9) and then The graphite crucible (9) is positioned inside the ceramic crucible (10). The resulting double layered crucible system, reaction furnace unit (1) inside protective cabinet (7) The induction coil (2) is placed in the center of the cabinet door (8) is closed. The protective cabinet (7) isolates the reaction area from environmental effects. 30 to ensure operator safety and, when necessary, under an inert atmosphere This allows for the study. The reaction takes place in a crucible containing the mixture, which is one aspect of the invention. induction heating operating in the frequency range of 1–100 kHz in the application It is being implemented. Temperature, power, frequency and time parameters are computer controlled. 13 The values ​​are entered as predefined set values ​​through the software system, and the system... It operates using a closed-loop (feedback) and PID-based control approach. induction heating via PC (11) connected to the power supply and control unit (3) Operating parameters (temperature, temperature levels, time, etc.) are determined using system-specific software. The recipe is defined in the specified format, and the induction heating process is based on these parameters. 5 It is executed automatically. Reaction zone temperature is measured using non-contact thermal methods. It is monitored by camera / thermocouple (12) and transmitted as feedback to the software and The measured values ​​are compared with the set values ​​and the power output is automatically adjusted. The system is adjusted. If the temperature exceeds the set value, the system will power up. reducing the output or stopping heating to return the temperature to the set value, 10 If critical limits are exceeded, the system automatically shuts down. Temperature of the reaction zone is continuously monitored with a non-contact thermal camera / thermocouple (12). or are monitored at specific intervals. Temperature levels of the heating program and Waiting times depend on the composition and properties of the raw materials to be used. is determined. By applying the determined temperature program, carbothermic reduction 15 The reaction is initiated, and by proceeding with the reaction in a controlled manner, iron-boron (Fe–B) formation of intermediate phases and iron monoboride (FeB) and iron diboride (Fe₂B) phases A ferroboron-based alloy powder structure is obtained. During the reaction... The temperature inside the graphite crucible (9) is above the inert atmosphere protective cabinet (7). 20 contactless via positioned thermal camera / thermocouple (12) is monitored and the reaction is left on the side surfaces of the inert protective cabinet (7) and is visually monitored through the left side viewing windows (6). When necessary, process parameters are updated via PC software (11). In one application of the invention, the temperature of the reaction mixture is in the range of 900–950 °C. is extracted. During this preheating phase, 25% of the boric acid is formed as a result of dehydration. water vapor, moisture from raw materials, bound water and volatile components removed from the environment, carbothermic reduction reactions take place. The necessary reaction conditions are being prepared. Following the preheating stage... The reaction temperature is increased to the range of 1250–1350 °C. At this stage, boron oxide is formed. and carbothermic reduction of iron oxides with carbon-based reducing agent 30 The kinetics of the reactions are enhanced, and the necessary steps for the formation of ferroboron phases are taken. The reaction conditions are met. Then, the temperature is increased to the range of 1550–1600 °C. It is extracted. In this stage, the reduction of boron oxide and the reaction of boron with iron take place. As a result, a ferroboron-based alloy powder containing FeB and / or Fe2B phases is formed. 14 Temperature and holding time are particularly important in determining the formation of the FeB phase and the resulting phase structure. The reaction is controlled in a way that ensures it becomes stable. After completion, the crucible is removed from the furnace and placed under ambient conditions. It is left to cool in the crucible without any further processing. This cooling process allows the formed FeB and 5 that will ensure the preservation of Fe₂B phases and the limitation of excessive grain growth It is carried out in this way. As a result of applying a controlled, staggered heating regime. The product is obtained directly in fine-grained or powder form instead of a bulk ingot. It can be done. Depending on the process conditions to be applied, the resulting product is ferrobor. the basic alloy powder structure, microstructural homogeneity, Fe–B distribution, carbon residue and Product purity is determined. Under suitable process conditions, at least 90% in powder form and 10% in pellet form. In this form, approximately 70–80% product purity is obtained. The product can be directly powdered or... It is obtained in fine-grained form, and the resulting ferroboron-based alloy powder The particle size is approximately in the range of 2–20 μm. Therefore, the product can be crushed, ground, and direct commercial without the need for similar mechanical size reduction processes It can be obtained in a usable form. Obtained by the method described in the invention, 15 The results of the XRD analysis performed on the ferroboron-based alloy powder are shown in Figure 3. The XRD analysis results showed that the sample was predominantly FeB, with a secondary phase. It has been determined that it contains Fe₂B. The dominance of FeB peaks indicates Fe₂B → FeB. its transformation is largely complete, low intensity graphite around ~26.5° The peak, however, indicates the presence of small amounts of residual carbon. The peaks are sharp and 20 The fact that it is distinct indicates that the resulting phases have a high degree of crystallization. is doing. The invention is a ferroboron-based alloy powder produced from solid raw materials containing iron and boron. 25 for the production of a carbothermic reduction method based on induction heating It is related to this. In the method, induction heating only involves the rapid heating of raw materials. or is not an energy source used for melting, but rather carbothermic reduction as the fundamental process component that determines how the reaction is carried out It is used. In this respect, the invention combines induction technology with traditional melting. Unlike other applications, directly initiating a solid-solid chemical reaction 30 and a production approach used to ensure it is maintained in a controlled manner. It offers. In traditional arc or shaft furnaces, heat is transferred from the furnace environment through reaction. It is introduced into the mixture from the outside. In the method described in the invention, however, electromagnetic eddy currents caused by the effect of the induction field and electrical resistance As a result of heating, heat is directly transferred within the induction-sensitive materials. This is done by heating the reaction mixture from the outside inwards, rather than from the inside out. It is heated rapidly and controllably throughout its volume. This difference is only due to the method used. It is not related to heating equipment but to temperature distribution, reaction kinetics, phase a fundamental process that directly affects the formation and microstructure of the final product 5 That is the difference. The method in question involves a double-layered structure consisting of graphite and ceramic components. This is carried out in a crucible system and under normal atmospheric pressure. The induction system uses different frequencies suitable for carrying out the reaction. It can be operated in the 1–100 kHz range in preferred applications. It is operated and the heating rate is controlled by the applied frequency and power values. The heating depth affected by the electromagnetic field is controlled. Heating process It is managed via computer-controlled automated software and the reaction zone Temperature is monitored using a non-contact thermal camera / thermocouple. The raw material system consists of boron, iron, and carbon resources. Boron oxide (B₂O₃) or boric acid (H₃BO₃) is used as a source of boron, and 15 is used as a source of iron. metallic iron powder, iron(III) oxide (Fe₂O₃) or iron(II,III) oxide (Fe₃O₄), and reduction Carbon is used as the source. The prepared raw material mixture is directly powdered. It can be used in the form, as well as in an application of the invention at a pressure below 5 bar. It can also be compressed and formed into pellets. However, it can be directly powdered. In production carried out in this form, a more homogeneous Fe–B distribution and higher product yield are achieved. Purity is obtained. The carbothermic reduction reaction, successively The process is carried out in stages of temperature. In the first stage, the reaction is initiated and Volatile components present in the raw materials are removed. In the second stage... The kinetics of reduction reactions are enhanced. In the final step, FeB and Fe₂B are formed. The formation of phases is ensured and the ferroboron-based alloy powder structure is stabilized. 25 is introduced. The gradual heating regime prevents the raw materials from being heated suddenly and uncontrollably. It prevents heating. Volatile matter removal, reduction reaction and ferroboron phases. It allows for the management of its formation at different temperature ranges. Controlled The increase in temperature also causes the raw materials to over-sinter, forming a monolithic block or limiting ingot formation and ensuring the product is available directly in powder or fine-grained form. 30 It contributes to the production of FeB and Fe₂B as a result of the reaction. A ferroboron-based alloy powder product containing the phases is obtained. The product is only a diffusion-limited layer formed on the surface of the starting materials not a homogeneous ferroboron formed throughout the entire volume of the reaction mixture 16 It has a basic alloy powder structure. Especially in production carried out in powder form. A homogeneous Fe–B distribution, fine-grained microstructure, and more regular phase distribution are obtained. It is produced. Under suitable process conditions, at least 90% of the product is in powder form, and in pellet form... The product in this form achieves approximately 70–80% product purity. The final product has a low purity level. It contains carbon residue at the level of 5 and is obtained directly in powder or fine-grained form. This is done. Therefore, crushing, grinding or mechanical sizing after production. Secondary operations such as downsizing are not needed or are significantly reduced. is reduced. Heat is generated directly in the reaction zone, and the furnace walls and It reduces heat losses through the environment and improves energy use efficiency. It increases. The high energy conversion efficiency of induction heating technology is 10 Therefore, compared to conventional heating methods under suitable process conditions, it is more efficient. It is known to have low energy consumption potential. Energy is only... directing the total energy consumption to the required reaction area; operating costs and carbon emissions resulting from energy use It contributes to its reduction. 15 The invention involves the carbothermic reduction of solid raw materials containing iron and boron. a ferroboron-based alloy based on induction heating, which relies on a chemical reaction. It relates to the powder production method. The main purpose of the method is to replace traditional melting and reprocessing methods. without the need for multi-stage production processes based on melting and refining, 20 Ferroboron-based alloy powder can be processed more quickly and directly into powder or fine granules. It is the process of obtaining raw materials in a specific form. In this context, induction technology is used not only for raw materials but also for... not as an auxiliary heating system that enables melting, but as a solid-solid chemical as the basic process unit that enables the reaction to be carried out directly It is used. Thus, the heating encountered in traditional oven systems is 25 eliminating inefficiencies, shortening process time, and crushing or grinding. The aim is to obtain a commercially viable product that does not require any additional resources. The heat required in this method is generated by a reaction based on the principle of electromagnetic induction. eddy currents occurring in the induction-sensitive components of the mixture and It is produced through hysteresis losses occurring in ferromagnetic materials. This 30 Therefore, heat is transferred from the outside to the reaction environment, as in conventional systems. Instead of being transferred, it occurs directly within the volume of material and the mixture It is heated from the inside out. The invention involves the formation of ferroboron-based alloy powder and carbon. between the source and the boron and iron sources under normal atmospheric pressure 17 It is based on the carbothermic solid-solid reaction that is carried out. Carbothermic In order to proceed with the reduction reaction in a controlled manner, a stepwise A heating regime is applied. In the first stage, the reaction is initiated and Volatile components present in the raw materials are removed. In the second stage... The kinetics of the reduction reactions are enhanced. In the final step, FeB and Fe₂B 5 are formed. The formation of phases is ensured and the ferroboron-based alloy powder structure is stabilized. This gradual temperature control prevents the reaction from occurring suddenly and uncontrollably. preventing its occurrence; reaction initiation, reduction rate and final phase This allows the organization to be managed independently of each other. When the reaction is complete, the product is a direct powder instead of a massive and monolithic structure. 10 or is obtained in fine-grained form. Thus, a conventional ferroboron-based alloy. Crushing, grinding, and mechanical size reduction, which may be necessary in powder production methods, Magnetic separation or remelting processes are not required, or these The number of steps is significantly reduced. The product is ready for commercial use at the furnace exit. It has a particulate form. The resulting product is mainly 15 FeB and Fe₂B phases. It contains a mixture. The invention primarily involves, rather than advanced purification processes, Control of the FeB–Fe₂B phase structure resulting from the reaction, microstructural Homogeneity and obtaining the product directly in fine-grained form are prioritized. It is maintained. The carbothermic reduction reaction is achieved through induction heating. implementation, traditional furnace-based and aluminothermic or magniothermic 20 It provides various technical effects compared to production approaches. Direct heat volumetric production within the reaction mixture, temperature, material mass more even distribution throughout and more simultaneous reaction in different regions This allows it to progress. This accelerates the reaction kinetics, thus increasing the overall... It contributes to shortening the process time. Volumetric and controlled heating 25 Thanks to this, temperature differences in the reaction environment are reduced, thus FeB and This ensures that the Fe₂B phases form in a more ordered and homogeneous manner. As a result, it has a finer grain, a more uniform phase distribution, and a more microstructural structure. A ferroboron-based alloy powder product with more reproducible properties is obtained. Instead of transferring heat from the external environment to the reaction vessel, it is transferred directly within the material. 30 Producing it reduces energy losses due to heat transfer and saves energy. It increases the efficiency of use. Furthermore, the induction system operates quickly and precisely. Being controllable allows for more efficient transitions between different temperature levels. It ensures the management and increased repeatability of process conditions. 18 Iron powder or iron oxides, along with starting materials like boron oxide or boric acid. The use of raw materials directly in a reaction environment, traditional melting and To reduce boron losses that may occur in refining-based processes and to increase boron levels. This can contribute to increasing the efficiency of use. Thus, the beginning The efficiency of converting raw materials into finished products is increased. The product is directly in powder or 5 Obtaining it in fine-grained form involves crushing, grinding, magnetic separation, and reprocessing. eliminating or significantly reducing additional processing steps such as melting Reducing the number of steps in the process shortens production time and saves energy. reducing consumption and process costs, limiting material losses and simplifies the production process. 10 The invention differs from multi-stage production approaches that require melting and reprocessing. Specifically, an integrated synthesis based on direct solid-solid reaction in the induction field. This approach allows for the use of different metallic and oxide-based irons. resources are utilized, process time and steps are reduced, and energy is saved. The efficiency of use is increased, a homogeneous microstructure and uniform phase distribution are obtained. It is processed and the final product can be produced directly in powder form. This difference Therefore, heat is not transferred to the reaction medium from the outside, but directly into the material volume. It is produced within it. Thus, the reaction is more balanced and uniform throughout the entire mass. This production principle makes it possible to advance the process time in a timely manner. shortening, increasing microstructural homogeneity, finer-grained and more uniform phase obtaining ferroboron-based alloy powder with a dispersion and improving product quality It ensures that it becomes repeatable. Furthermore, the starting raw materials... direct use and multi-stage melting, remelting and refining By reducing these processes, boron losses, energy consumption and production costs are reduced by 25%. It is being reduced. The invention utilizes the known carbothermal method in the production of ferroboron-based alloy powders. carrying out the reduction reaction, as well as producing the heat required for the reaction and induction heating which has radically changed the way it is transferred to the reaction medium. It presents a fundamental process approach. The main difference in this context is the heat. Instead of transferring the reaction medium from the outside, as in classic furnace systems, 30 eddy currents and electrical currents resulting from electromagnetic induction It is produced directly within the volume of the material through resistance-induced heating. Therefore, the difference in question is simply between one heating appliance and another. It does not involve changing the reaction kinetics, temperature distribution, or phase. 19 a fundamental factor that directly affects the formation, product microstructure and process control It is a process transformation. The invention utilizes the rapid, volumetric, and efficient methods provided by induction heating. Thanks to controlled heat generation, different regions of the reaction mixture are more stable. It is heated in this way. This ensures a homogeneous temperature distribution in conventional ovens. The need for complex heating zones used for this purpose is eliminated. 5 or is significantly reduced. Frequency and power applied in the induction system. The ability to control the values, heating depth and temperature increase rate of the process This allows the energy input to be adjusted according to the requirements. directing the reaction directly to the area where the reaction takes place and making the reaction more It ensures precise management. Within the scope of the invention, the temperature is 1600 °C in 10 The temperature is raised to this level and a gradual heating regime is applied. Initial temperature initiating the reaction and removing volatile components in the first stage, second Enhancing reaction kinetics in the first step and forming FeB and Fe₂B phases in the final step. By creating and stabilizing it, the temperature is thus only determined at the final level. It is not increased to a certain value. Reaction initiation, reduction rate and phase formation 15 It is managed in successive controlled stages. The raw material system is also... in accordance with the aforementioned induction-assisted carbothermic reduction process It is formed using boron oxide or boric acid as a boron source, and iron as a source. metallic iron powder or iron oxides and carbon as a reducing agent It is used. 20 formed by the combined use of boron, iron and carbon resources. In a carbothermic reduction environment, boron oxide is reduced via carbon, and iron is also reduced. It reacts with raw materials containing ferroboron phases to form them. Therefore, the method involves a coating that occurs on the surface and is limited by diffusion, or Unlike the boronizing process, it is based on reaction kinetics and the entire material It is a direct synthesis method that progresses in volume. The heat within the reaction medium is 25 volumetric production means that the reaction occurs only on the outer surface of the mixture or in specific areas. not in hot regions, but more synchronously throughout the entire mass of material. It enables progress. As a result, a superficial or regional product Instead of forming a homogeneous ferroboron-based alloy powder containing FeB and Fe₂B phases. The structure is obtained. In particular, the formation of the FeB phase is achieved at the applied temperature levels of 30. and can be controlled through raw material ratios. Homogeneous temperature distribution. and the fact that the reaction proceeds throughout the entire volume, regional temperature differences and It reduces microstructural heterogeneity. Thus, it results in finer-grained, more regular and a ferroboron-based alloy powder product with a more uniform phase distribution is obtained This is achieved through a multi-stage heating regime and controlled raw material composition, ferrobor. more controlled formation of the phase structure of the alloy powder and unwanted This contributes to limiting phase formations. This situation improves product properties. This contributes to greater stability and repeatability across production batches. The rapid temperature increase and volumetric heat generation provided by induction heating is comparable to carbothermic 5 It improves the kinetics of the reduction reaction and shortens the total production time. It ensures that the reaction occurs more quickly and in a more stable manner. completion improves process efficiency while avoiding long-term furnace operation. It also reduces the resulting energy consumption. This ensures energy efficiency. energy consumption, operating costs and carbon footprint associated with energy use are being increased. Emissions can be reduced. In addition, electrode consumption encountered in arc furnaces, electrode-induced fouling, high refractory wear, and heterogeneous temperature zones. Problems like these are largely eliminated in the induction-based manufacturing approach. is being removed. Another important technical effect of the invention is the ferroboron-based alloy powder. The product can be obtained directly in powder or fine-grained form. The product is available in bulk and 15 Because it does not form a monolithic structure, in traditional methods, after production... The crushing, grinding, and mechanical size reduction processes that need to be applied It is not heard. Eliminating these processes simplifies the process, production shortening the duration, reducing energy consumption and equipment needs It provides. It also reduces the risk of damage during crushing and grinding operations. potential product losses, contamination and irregular particle size formation This is prevented. The invention does not constitute an equivalent of a known method or a routine procedure. It's not just about changing equipment. Induction heating directly works on solid-to-solid processes. Its use in reaction-based ferroboron-based alloy powder synthesis; reaction mechanism, temperature control, reaction kinetics, phase formation, product form 25 and introduces a unique production approach that holistically transforms energy use. It places. Thanks to the production method described in the invention;  Rapid and homogeneous heating throughout the material volume, 30  shorter reaction and production time,  Homogeneous FeB and Fe₂B phase structure spread throughout the entire volume,  finer-grained and more controlled microstructure,  Improved phase formation and product repeatability, 21  Obtaining powder or fine-grained products directly,  elimination of secondary processes such as crushing and grinding,  lower heat loss and higher energy use efficiency,  reduced production costs and carbon emissions associated with energy use,  a more precise, stable and controllable production process 5 is provided. 15 25

Claims

22 REQUESTS 1. Induction heating-based carbothermic ferroboron-based alloy powder production method its characteristic is, i. diboron trioxide (B₂O₃) with ≥98% purity or equivalent as a boron source. Boric acid (H₃BO₃), with a powder size of ≤50 μm and ≥ 99% carbon source. As a source of carbon and iron, ≥99% pure fine powdered iron. or by using equivalent iron oxides, the amount of boron oxide is stoichiometric. raw material powder components will be 2-4% higher than the value preparation, 10 ii. A homogeneous reaction mixture of the prepared raw material powder components. to obtain, bring to the same grain size structure and between the components mechanical mixing and / or ball bearing to increase contact effectiveness homogenization by subjecting it to a grinding process, iii. The initial reaction charge of the homogenized reaction mixture is 15 graphite is used directly in powder form in the reaction mixture. to be placed inside the basket (9), or ensuring load integrity, transport and / or feeding into the system Depending on application requirements such as ease of use, reaction 20 by applying a compression pressure of ≤5 bar while preserving its porosity The reaction mixture is brought into pellet form and placed in a graphite crucible (9). placement, iv. positioning the graphite crucible (9) inside the ceramic crucible (10) and double The layered crucible system isolates the reaction zone from environmental influences. 25 providing operator safety and an inert atmosphere when necessary. reaction furnace inside protective cabinet (7) suitable for working under placement of the induction coil (2) in unit (1) in the center of unit (1) and closing the protective cabin door (8), v. induction heating of the mixture operating in the frequency range of 1–100 kHz 30 heating by the system, vi. Carbothermic reduction reaction by applying the temperature program initiation and controlled progression of the iron-boron reaction 23 Formation of (Fe–B) interfaces and iron monoboride (FeB) with iron Obtaining a ferroboron structure containing diboride (Fe₂B) phases, vii. After the completion of the reaction, the product is induction coil (2) controlled cooling inside and the cooled product is graphite Ferroboron-based alloy 5 obtained in the form of 2-20 μm by taking from the crucible (9) obtaining the powder It includes the steps of the process.

2. A method for producing ferroboron-based alloy powder according to Claim 1, the characteristic of which is mentioned. boron oxide (B₂O₃) with a purity of ≥98% of the boron source or boron with a purity of ≥98% Boric acid (H₃BO₃), iron (Fe) powder with iron source purity ≥99%, Iron-10 III Oxide (Fe₂O₃) or Iron-II,III Oxide (Fe₃O₄) and the purity of the reducing source It means that it contains ≥99% carbon.

3. Ferroboron-based in the form of 2-20 μm produced by a method according to claim 1 or 2. alloy powder. 20 30 35 40

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