Low-phosphorus clean high-manganese steel frog and production method thereof

Abstract

The invention provides a low-phosphorus clean high-manganese steel frog and a production method thereof, and the low-phosphorus clean high-manganese steel frog comprises the following components in percentage by mass: 1.1-1.3% of C, 11.0-13.0% of Mn, less than or equal to 0.5% of Si, less than or equal to 0.03% of P, less than or equal to 0.02% of S, 1.5-2.5% of Cr, 0.02-0.05% of N and the balance of Fe and inevitable impurities. And low-temperature dephosphorization is conducted, slag composition is dynamically adjusted in a time-division-step mode, and argon is blown to the bottom of a steel ladle to be combined with LF refining production. The slag is reasonably designed, the phosphorus content of the high-manganese steel is reduced, and the problem that product components are unqualified due to the fact that the phosphorus content of a high-manganese steel finished product produced according to the prior art is too high is effectively solved; the purpose of cleaning the molten steel is achieved by blowing air into the molten steel, inclusions in the steel are removed to the maximum extent, and the service life of the high-manganese steel is prolonged; sulfur, oxygen, nitrogen and inclusions are removed through LF refining, the quality of a finished product is improved, and the service life of the product is prolonged.

Description

Technical Field

[0001] This invention belongs to the field of chemical metallurgy high manganese steel production technology, specifically relating to a low-phosphorus clean high manganese steel turnout and its production method. Background Technology

[0002] Railway frogs are an important component of railway tracks, their main function being to transfer wheels from one rail to another. High-manganese steel, due to its high strength, high hardness, and high wear resistance, is commonly used as the casting steel for railway frogs. In recent years, my country's railways have developed rapidly, and heavy-haul railways, as an important part of the railway system, have received widespread attention due to their advantages such as large transport capacity, high efficiency, and low transportation costs.

[0003] However, the increasing heavy-haul transportation of railways has led to increasingly harsh service conditions for railway frogs, significantly shortening their service life. Phosphorus is a harmful element in steel; excessive phosphorus levels in steel result in increased cold brittleness, reduced plasticity and toughness, and deteriorated weldability, seriously endangering the lives and property of the people. Since scrap steel, alloy raw materials, and slag-forming materials contain phosphorus, a large amount of phosphorus enters the molten steel during the smelting process. Therefore, how to remove phosphorus from steel is a crucial issue in the clean production of high-manganese steel.

[0004] Furthermore, under current technology, the electric arc furnace smelting of high-manganese steel also presents the problem of increased nitrogen and oxygen content in the steel due to air ionization caused by the electric arc. Nitrogen in steel reduces its mechanical properties and is a major cause of defects such as cracks, subcutaneous bubbles, and central porosity; while oxygen in steel combines with alloying elements to form non-metallic inclusions, which remain in the steel during solidification, reducing its plasticity, toughness, and fatigue performance, while also causing the loss of alloying elements. In order to enhance the safety of railway transportation and extend the service life of turnouts, the clean production of high manganese steel is one of the main approaches. The following improvement technical solutions are proposed. Summary of the Invention

[0005] The technical problem solved by this invention is to provide a low-phosphorus, clean high-manganese steel frog and its production method, thereby solving the technical problem of how to reduce the phosphorus content of high-manganese steel frogs and remove nitrogen, oxygen and inclusions.

[0006] The technical solution adopted in this invention is: a low-phosphorus clean high-manganese steel fork, which, by mass percentage, comprises the following components: C: 1.1-1.3%, Mn: 11.0-13.0%, Si≤0.5%, P≤0.03%, S≤0.02%, Cr: 1.5-2.5%, N: 0.02-0.05%, with the balance being Fe and unavoidable impurities.

[0007] A method for producing low-phosphorus, clean, high-manganese steel frogs involves dynamically adjusting the slag composition in stages during low-temperature dephosphorization and refining using bottom blowing argon gas combined with LF refining in the ladle. The method includes the following steps: S1. Melting: Before feeding scrap steel into the electric arc furnace, add 120-160 kg of lime, 30-70 kg of fluorite, 20-40 kg of limestone and 10-20 kg of iron ore to the bottom of the furnace and spread them evenly. Then add 8-10 t of scrap steel, turn on the power to smelt and enter the melting period, during which slag removal operation is carried out.

[0008] S2. Assisted melting: When the scrap steel is 60% melted, the power is turned off and 20-60 kg of lime is added. Then the power is turned on for smelting and oxygen is blown to assist melting.

[0009] S3. Making oxidation slag: After the furnace charge is melted and cleared, add 70-80 kg of lime, 40-60 kg of fluorite, 30-45 kg of limestone and 80-120 kg of iron ore to make oxidation slag. Then, turn on the electric smelting to enter the oxidation period. The entire process is slag flow operation.

[0010] S4. Oxygen Decarburization: After slag formation, oxygen decarburization begins when the molten pool temperature reaches ≥1560 ℃; the oxygen decarburization rate is 0.01~0.02% per minute, the total decarburization amount is ≥0.40%, and net boiling is maintained for more than 5 minutes; when the carbon content of the molten steel reaches the range of 0.10~0.20%, oxidation is stopped, and the oxidation endpoint is C≤0.2% and P≤0.005%.

[0011] S5. Remove slag: When the oxidation endpoint C≤0.2% and P≤0.005%, power off the machine and remove all the slag.

[0012] S6. Making reducing slag: Add 80-120 kg of lime and 30-70 kg of fluorite to make reducing slag, and add carbon powder and silicon carbide powder as reducing agents; the amount of carbon powder added is 3-6 kg per ton of molten steel, and the amount of silicon carbide powder added is 2-5 kg ​​per ton of molten steel. Then, turn on the electric smelting to enter the reduction period.

[0013] S7. Pre-deoxidation: Add silicon-manganese alloy for pre-deoxidation. The amount of silicon-manganese alloy added is 5-15 kg per ton of molten steel.

[0014] S8. Final Deoxidation: The temperature of the molten steel is 1485~1500 ℃, and a deoxidizer is added to the ladle for final deoxidation. Argon gas is blown in during the process, and the steel is tapped after the steel composition sample is qualified.

[0015] S9, LF Refining: After tapping, remove the argon blowing pipe and hoist it into the LF refining station. During LF refining, argon gas is blown in again. During LF refining, samples are taken and the content of each alloying element in the molten steel is adjusted according to the sample results, so that Mn: 11.0~13.0% and Cr: 1.5~2.5%.

[0016] S10. Casting: After the molten steel temperature is 1450~1465 ℃ and the chemical composition of the molten steel is qualified, the argon gas pipe is removed and the steel is hoisted into the casting station for casting to obtain the required high manganese steel turnout.

[0017] In the above technical solution, further: the 20-60 kg of lime added in step S2 is replaced by 40-80 kg of limestone; the oxygen blowing pressure in step S2 is 0.5-0.8 MPa.

[0018] In the above technical solution, the preferred method is: in step S3, the amount of slag is maintained at 2-3% of the amount of molten steel, and slag is added in time when the amount of slag is insufficient.

[0019] In the above technical solution, the preferred method is as follows: during step S4 oxygen blowing decarburization, the oxygen blowing pipe is inserted into the shallow blowing pool 50-200 mm below the surface of the molten steel at a 30° angle, the shallow blowing time is ≤3 min, and the oxygen blowing pressure is 0.5-0.8 MPa.

[0020] In the above technical solution, further: after pre-deoxidation in step S7, ferrochrome and ferromanganese are added to adjust the alloy composition in the molten steel according to the sample results.

[0021] In the above technical solution, preferably: the deoxidizer in step S8 is a silicon-barium-calcium composite deoxidizer, and the amount added is 10-20 kg; the argon blowing pressure in step S8 is 0.05-0.2 MPa.

[0022] In the above technical solution, the preferred method is to use an argon blowing pressure of 0.2 to 0.3 MPa and an argon blowing time of 5 to 10 min in step S9.

[0023] In the above technical solution, further: during LF refining in step S9, lime, fluorite and deoxidizer are added according to the slag condition, so that the amount of slag is 2 to 4% of the amount of molten steel.

[0024] An application of a low-phosphorus clean high-manganese steel frog, which is used in heavy-haul railways.

[0025] Advantages of this invention compared to existing technologies: 1. This invention features a rational slag design that reduces the phosphorus content in high-manganese steel, effectively solving the problem of excessively high phosphorus content in finished high-manganese steel products produced using existing technologies, which leads to substandard product composition.

[0026] 2. This invention achieves the purpose of cleaning molten steel by blowing air into it, thereby removing inclusions in the steel to the maximum extent and improving the service life of high manganese steel.

[0027] 3. The LF refining process of this invention removes sulfur, oxygen, nitrogen and inclusions, improving the quality of the finished product and extending its service life.

[0028] 4. The lime, fluorite, limestone and iron ore added during the melting process in step S1 of this invention can act as fluxes to lower the melting point of the slag, accelerate the melting of scrap steel, form high-alkalinity slag, and remove phosphorus; improve the stability of electric arc melting, increase melting efficiency, shorten the smelting cycle, and improve production efficiency; extend the service life of the furnace bottom refractory material and reduce costs; reduce the emission of harmful gases from smoke and dust, improve the environment, and reduce pollution.

[0029] 5. In step S2 of this invention, adding lime can adjust the slag alkalinity, which is more conducive to the removal of harmful elements such as phosphorus and sulfur; it forms low-melting-point slag, which accelerates the melting of scrap steel; oxygen blowing assists melting, which rapidly increases the furnace temperature, shortens the melting time, improves smelting efficiency, and improves the quality and performance of steel; limestone replaces lime, which is cheaper and significantly reduces costs, effectively utilizing natural resources; limestone decomposes to produce calcium oxide, which plays a role in slag formation and dephosphorization; in addition, the carbon dioxide gas produced by limestone decomposition also helps to improve the thermal efficiency of the electric arc and promote the smelting reaction.

[0030] 6. The lime and limestone added in step S3 of this invention can significantly increase the alkalinity of the slag, which is beneficial for the removal of harmful elements such as phosphorus and sulfur. The addition of fluorite and iron ore helps to adjust the viscosity of the slag, which is beneficial for the slag fluidity and metallurgical reaction, and helps to reduce smelting energy consumption. As an oxidant, iron ore can enhance the oxidizing properties of the slag, which is beneficial for oxidation decarburization, dephosphorization and other reactions, forming a stable oxidized slag, effectively removing harmful impurities in molten steel, and improving the purity and quality of molten steel.

[0031] 7. The relatively stable decarburization rate in step S4 of this invention can precisely control the carbon content in molten steel to meet the requirements of subsequent smelting and casting processes; the molten pool temperature control ensures that the slag is fully formed, providing sufficient heat for the decarburization reaction; the precise control of oxygen blowing time and rate enables precise control of the carbon content in molten steel; the oxidation endpoint control ensures that the carbon and phosphorus content in molten steel can be stabilized within the target range to meet the requirements of high-quality products; oxygen blowing decarburization, the full reaction between slag and molten steel helps to remove impurity elements in molten steel, improving the purity and uniformity of molten steel.

[0032] 8. In step S5 of this invention, all slag is removed, effectively removing impurities such as phosphorus and sulfur from the molten steel, improving the purity and quality of the steel, avoiding secondary pollution, preventing damage to equipment from corrosive chemicals in the slag at high temperatures, preventing slag accumulation from clogging the tap hole or slag discharge port of the electric arc furnace, reducing waste emissions generated during the electric arc furnace smelting process, and enabling the recovery and utilization of useful components in the slag such as iron and calcium. The slag removal operation is simple and convenient, requiring no complex equipment or processes, and the power outage operation ensures the safety of the operators.

[0033] 9. The lime and fluorite added in step S6 of this invention can adjust the composition of the slag, making it more reducing, reducing oxides in molten steel to metallic elements, and improving the purity and quality of the molten steel. Carbon powder and silicon carbide powder act as reducing agents, accelerating the reduction reaction of oxides. By precisely controlling the amount of reducing agent added and the smelting time, the degree of reduction can be precisely controlled, ensuring that oxides can be fully reduced, while avoiding excessive reduction that would lead to a decline in the quality of molten steel, thus improving the purity of the molten steel. Compared with traditional smelting methods, this invention reduces environmental pollution, reduces energy consumption, improves smelting efficiency, reduces operational difficulty and cost, ensures operational safety, and avoids accidents.

[0034] 10. In step S7 of this invention, both manganese and silicon elements in the silicon-manganese alloy can react with oxygen in molten steel to form oxides and remove excess oxygen. Compared with other deoxidizers, the silicon-manganese alloy has a higher deoxidation efficiency. The silicon-manganese alloy is not only a deoxidizer, but also an important alloying additive that can adjust the chemical composition of steel and improve its mechanical and processing properties.

[0035] 11. In step S8 of this invention, final deoxidation involves adding a deoxidizer. The selection of a specific temperature ensures the smooth progress of the deoxidation reaction while avoiding excessive burning of the deoxidizer due to excessive temperature. Argon is blown into the molten steel for stirring, saving energy and reducing consumption while protecting the molten steel from pollution by harmful gases such as oxygen and nitrogen in the air, further purifying the steel. Precise temperature control and effective utilization of the deoxidizer in the final deoxidation process reduce energy waste and deoxidizer consumption, thus lowering environmental pollution. The silicon-barium-calcium composite deoxidizer uses silicon, barium, calcium, and other elements to chemically react with oxygen in the molten steel, generating oxide impurities, thereby achieving efficient deoxidation and improving the steel's machinability and corrosion resistance. The generated oxide impurities can act as heterogeneous nucleation sites, refining the steel's grains, thereby improving the steel's mechanical and processing properties, as well as its purity and density.

[0036] 12. The LF refining in step S9 of this invention enhances the thermodynamic and kinetic conditions of the metallurgical reaction, achieving refining effects such as deoxidation, desulfurization, alloying, and temperature increase in a short time; it has high deoxidation efficiency, reducing the oxygen content in molten steel; it has strong desulfurization capacity; by controlling the composition and basicity of the refining slag, as well as the strong stirring effect of bottom-blown argon, the desulfurization effect is significantly improved; argon blowing and stirring accelerate the uniformity of temperature and composition in the molten steel, quickly and accurately adjusting the complex chemical composition, especially removing Al2O3 inclusions; the addition of lime in LF refining can increase the basicity of the slag, further facilitating the desulfurization reaction; the addition of fluorite improves the slag fluidity by lowering the slag melting point, which helps to fully contact the slag-steel interface and accelerates the metallurgical reaction. Attached Figure Description

[0037] Figure 1 This is a process flow diagram of the production method of the present invention; Figure 2 This is the design concept of the chemical process route for this invention; Detailed Implementation

[0038] The following will be combined with the present invention. Figures 1-2 The present invention provides specific embodiments, clearly and completely describing the technical solutions in these embodiments. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0039] Example 1: A low-phosphorus clean high-manganese steel fork, comprising the following components by mass percentage: C: 1.1%, Mn: 11.0%, Si: 0.3%, P: 0.01%, S: 0.01%, Cr: 1.5%, N: 0.02%, with the balance being Fe and unavoidable impurities.

[0040] Example 2: A low-phosphorus clean high-manganese steel fork, comprising the following components by mass percentage: C: 1.2%, Mn: 12%, Si: 0.4%, P: 0.02%, S: 0.01%, Cr: 2%, N: 0.03%, with the balance being Fe and unavoidable impurities.

[0041] Example 3: A low-phosphorus clean high-manganese steel fork, comprising the following components by mass percentage: C: 1.3%, Mn: 13.0%, Si: 0.5%, P: 0.03%, S: 0.02%, Cr: 2.5%, N: 0.05%, with the balance being Fe and unavoidable impurities.

[0042] A method for producing low-phosphorus clean high-manganese steel frogs involves dynamically adjusting the slag composition in stages during low-temperature dephosphorization and refining the process using bottom blowing argon gas combined with LF refining in the ladle.

[0043] The principle of this method is analyzed as follows: the thermodynamic conditions for steel dephosphorization are 1) low temperature; 2) high basicity slag formation; 3) high oxidizing slag formation; and 4) large slag volume. During electric arc furnace steelmaking, the molten steel temperature is relatively low during the melting period, which is most suitable for the dephosphorization reaction. As smelting progresses, the molten steel temperature gradually increases, and the thermodynamic conditions for the dephosphorization reaction gradually worsen. However, appropriately increasing the temperature can promote a reduction in slag viscosity, improve the dephosphorization kinetics, and accelerate the dephosphorization reaction. Furthermore, the dephosphorization reaction is an interfacial reaction between steel and slag; the larger the contact area between the molten steel and the slag, the faster the dephosphorization rate. Therefore, increasing the contact area between the steel and slag is also crucial for the dephosphorization reaction. This can be achieved by adding limestone to generate gas through thermal decomposition or by blowing in gas for stirring, allowing the generated bubbles to expand the steel-slag interface as they pass through, thereby accelerating the dephosphorization reaction rate. The favorable low temperature conditions during the melting period can be fully utilized by adding limestone to improve the kinetics and effectively remove harmful phosphorus elements from the steel. Therefore, comprehensively considering factors such as slag oxidizability, basicity, melting temperature, and viscosity, reasonable slag design and full utilization of the low-temperature conditions during the melting period are key to smelting clean high-manganese steel. Based on this, introducing an LF refining process after electric arc furnace steelmaking can efficiently remove sulfur, oxygen, nitrogen, and inclusions from the steel, achieving the goal of further purifying the high-manganese steel.

[0044] Example 1: A method for producing low-phosphorus, clean, high-manganese steel frogs specifically includes the following steps: S1. Melting: Before feeding scrap steel into the electric arc furnace, add 120 kg of lime, 30 kg of fluorite, 20 kg of limestone and 10 kg of iron ore to the bottom of the furnace and spread them evenly. Then add 8 t of scrap steel, turn on the power to smelt and enter the melting period, during which slag removal operation is carried out.

[0045] It should be noted that, similar to other embodiments, the lime, fluorite, limestone, and iron ore added in step S1 act as fluxes, helping to lower the melting point of the slag and thus accelerating the melting process of scrap steel. These additives react with impurities in the scrap steel to form low-melting-point slag, which helps the scrap steel melt faster. High-alkalinity slag effectively removes phosphorus from the scrap steel. Due to the presence of the molten pool, the stability of the electric arc during the melting period is improved. This helps reduce arc flickering and jumping, allowing the arc energy to be transferred to the scrap steel more stably, thereby improving melting efficiency. The combined effect of a stable arc and an accelerated melting process significantly improves melting efficiency. This helps shorten the smelting cycle and increase production efficiency. The molten slag layer in the slag-flowing operation protects the refractory material at the furnace bottom from direct erosion by the electric arc and the corrosion of the high-temperature molten slag. This helps extend the service life of the furnace bottom refractory material and reduce production costs. The slag-flowing operation helps reduce the emission of smoke and harmful gases during the smelting process, thereby improving the smelting environment and reducing environmental pollution.

[0046] S2. Assisted melting: When the scrap steel is 60% melted, the power is turned off and 20 kg of lime is added. Then the power is turned on for smelting and oxygen is blown to assist melting.

[0047] It should be noted that, similar to other embodiments, adding lime in step S2 adjusts the alkalinity of the slag, making it more conducive to the removal of harmful elements such as phosphorus and sulfur. Simultaneously, the addition of lime can react with impurities in the scrap steel to form low-melting-point slag, which helps accelerate the melting process. Oxygen blowing significantly increases the furnace temperature and accelerates the melting of scrap steel. During oxygen blowing, oxygen reacts with carbon in the scrap steel, generating a large amount of heat, causing the furnace temperature to rise rapidly. At the same time, oxygen can also cut the charge, making it easier to melt. Oxygen blowing significantly shortens the melting time, thereby improving smelting efficiency. Oxygen blowing reduces the power consumption of the electric arc furnace. Oxygen blowing reduces the emission of smoke and harmful gases during the smelting process. By optimizing the slag composition and using oxygen blowing, impurities and harmful gases in the scrap steel can be removed more effectively, thereby improving the quality and performance of the steel.

[0048] In the above embodiment, the 20 kg of lime added in step S2 is replaced by 40 kg of limestone; the oxygen blowing pressure in step S2 is 0.5 MPa.

[0049] It should be noted that, similar to other embodiments, limestone is significantly cheaper than lime. Replacing some lime with limestone can significantly reduce production costs. Limestone is a widely distributed mineral resource in nature, and using it as a raw material for steelmaking helps to achieve the effective utilization of natural resources. Although lime is more reactive than limestone, under appropriate process conditions, limestone can decompose to produce calcium oxide, which also serves the functions of slag formation and dephosphorization. Furthermore, the carbon dioxide gas produced by the decomposition of limestone helps to improve the thermal efficiency of the electric arc and promotes the smelting reaction.

[0050] S3. Making Oxidizing Slag: After the furnace charge is melted and cleared, 70 kg of lime, 40 kg of fluorite, 30 kg of limestone, and 80 kg of iron ore are added to make oxidation slag. The process is then initiated by electrosmelting to enter the oxidation period, with slag flow throughout. In the above embodiment, preferably, step S3 maintains the slag amount at 2% of the molten steel amount, and slag is added promptly when the slag amount is insufficient.

[0051] It should be noted that, similar to other embodiments, the lime and limestone added in step S3 significantly increase the basicity of the slag, which is beneficial for the removal of harmful elements such as phosphorus and sulfur. The addition of fluorite and iron ore helps adjust the viscosity of the slag, keeping it within an appropriate range. Appropriate viscosity is beneficial for slag fluidity and metallurgical reactions, while also helping to reduce energy consumption during the smelting process. Iron ore, as an oxidant, enhances the oxidizing properties of the slag, which is beneficial for decarburization and dephosphorization reactions during the oxidation period. By forming a stable oxide slag, harmful impurities in the molten steel can be effectively removed, improving the purity and quality of the steel. Optimized slag composition and properties help shorten smelting time and reduce production costs. Full-process slag flow operation promotes stirring of the molten pool, making the molten steel and slag more uniformly mixed, which is beneficial for metallurgical reactions. It also makes slag-metal separation easier, reduces slag erosion of the furnace lining, and extends the service life of the furnace lining.

[0052] S4. Oxygen Decarburization: After slag formation, oxygen decarburization begins when the molten pool temperature reaches ≥1560 ℃; the oxygen decarburization rate is 0.01% per minute, the total decarburization amount is ≥0.40%, and net boiling is maintained for more than 5 minutes; when the carbon content of the molten steel reaches within the range of 0.10%, oxidation is stopped, and the oxidation endpoint is C≤0.2% and P≤0.005%.

[0053] In the above embodiments, preferably: during step S4 oxygen blowing decarburization, the oxygen blowing pipe is inserted into the shallow blowing pool 50 mm below the surface of the molten steel at a 30° angle, the shallow blowing time is ≤3 min, and the oxygen blowing pressure is 0.5 MPa.

[0054] It should be noted that, similar to other embodiments, the relatively stable decarburization rate in step S4 helps to precisely control the carbon content in the molten steel. The total decarburization amount ensures a significant reduction in the carbon content of the molten steel to meet the requirements of subsequent smelting and casting processes. Control of the molten pool temperature ensures that the slag has fully formed and provides sufficient heat for the decarburization reaction. Precise control of the oxygen blowing time and rate allows for precise control of the carbon content in the molten steel. Controlling the oxidation endpoint to stop oxidation ensures that the carbon content in the molten steel remains stable within the target range, ensuring that the carbon and phosphorus content meets the requirements for high-quality steel products. During oxygen decarburization, the sufficient reaction between the slag and molten steel helps remove impurity elements from the molten steel, improving its purity and uniformity. Oxygen decarburization technology reduces energy consumption by improving smelting efficiency. Simultaneously, precise temperature and carbon content control also contribute to reduced energy consumption. Compared to traditional decarburization methods, oxygen decarburization technology is more environmentally friendly. Precise control of the oxygen blowing time and rate reduces exhaust emissions and environmental pollution.

[0055] S5. Remove slag: When the oxidation endpoint C≤0.2% and P≤0.005%, power off the machine and remove all the slag.

[0056] It should be noted that, similar to other embodiments, step S5 involves completely removing the slag, effectively removing impurities such as phosphorus and sulfur from the molten steel. This reduces the content of these elements in the molten steel, improves its purity and quality, avoids secondary pollution, reduces energy and raw material consumption during smelting, ensures the smooth progress of the smelting process, prevents corrosive chemicals in the slag from damaging equipment at high temperatures, avoids slag accumulation that blocks the electric arc furnace taphole or slag discharge port, reduces waste emissions during electric arc furnace smelting, and enables the recovery and utilization of useful components in the slag, such as iron and calcium. The slag removal operation is relatively simple and convenient, requiring no complex equipment or processes, and the power outage operation ensures the safety of the operators.

[0057] S6. Making reducing slag: Add 80 kg of lime and 30 kg of fluorite to make reducing slag, and add carbon powder and silicon carbide powder as reducing agents; the amount of carbon powder added is 3 kg per ton of molten steel, and the amount of silicon carbide powder added is 2 kg per ton of molten steel. Then, turn on the electric smelting to enter the reduction period.

[0058] It should be noted that, similar to other embodiments, the lime and fluorite added in step S6 adjust the slag composition, giving it better reducibility. During the reduction period, the oxides in the molten steel are reduced to metallic elements, improving the purity and quality of the steel. The addition of fluorite helps adjust the slag viscosity, keeping it within an appropriate range. Appropriate viscosity is beneficial for slag fluidity and metallurgical reactions, while also helping to reduce energy consumption during the smelting process. Carbon powder and silicon carbide powder, as reducing agents, accelerate the reduction reaction of oxides in the molten steel. By precisely controlling the amount of reducing agent added and the smelting time, precise control of the degree of reduction can be achieved, ensuring that the oxides in the molten steel are fully reduced while avoiding over-reduction that leads to a decline in steel quality. The processes of creating reducing slag and adding reducing agents help remove oxides and other impurities from the molten steel, improving its purity and stabilizing its composition to meet the requirements of high-quality steel products. Compared with traditional smelting methods, the processes of creating reducing slag and adding reducing agents help reduce waste gas emissions and environmental pollution. Optimizing slag composition and adjusting the smelting process helps reduce energy consumption and improve smelting efficiency. The processes of preparing reducing slag and adding reducing agents are relatively simple and convenient, requiring no complex equipment or processes, which helps reduce operational difficulty and costs. During the smelting process, precise control of the amount of reducing agent added and the smelting time ensures operational safety and prevents accidents.

[0059] S7. Pre-deoxidation: Add silicon-manganese alloy for pre-deoxidation. The amount of silicon-manganese alloy added is 5 kg per ton of molten steel.

[0060] It should be noted that, similar to other embodiments, both manganese and silicon in the ferrosilicon alloy in step S7 react with oxygen in the molten steel to form oxides, effectively removing excess oxygen. This deoxidation process is crucial for improving the quality and performance of steel. Compared to other deoxidizers, ferrosilicon alloy has a higher deoxidation efficiency, rapidly reducing the oxygen content in molten steel and creating favorable conditions for subsequent smelting processes. Ferrosilicon alloy is not only a deoxidizer but also an important alloying additive. By adding an appropriate amount of ferrosilicon alloy, the chemical composition of steel can be adjusted, improving its mechanical and processing properties. Specifically, silicon increases the strength of steel, while manganese enhances its toughness. These performance optimizations make steel products more suitable for various complex and harsh operating environments. The market price of ferrosilicon alloy is relatively stable, and its cost-effectiveness is good, further reducing smelting costs. The production and use of ferrosilicon alloy are relatively environmentally friendly, with less pollution. Adding ferrosilicon alloy in the pre-deoxidation stage can reduce exhaust emissions and dust generation, minimizing negative environmental impacts. The pre-deoxidation effect of silicon-manganese alloys helps to shorten the smelting cycle and improve smelting efficiency.

[0061] In the above embodiments, further: after pre-deoxidation in step S7, ferrochrome and ferromanganese are added to adjust the alloy composition in the molten steel according to the sample results.

[0062] It should be noted that, similar to other embodiments, by accurately measuring and analyzing the sample results, the content of each element in the molten steel can be accurately determined, allowing for the targeted addition of alloying materials such as ferrochrome and ferromanganese, thus achieving precise adjustment of the alloy composition of the molten steel. Different steel products have different requirements for alloy composition. By adding alloying materials such as ferrochrome and ferromanganese, steel products with specific alloy compositions can be customized according to customer needs and product design requirements. Chromium significantly improves the strength and hardness of steel, especially maintaining good mechanical properties at high temperatures. Manganese enhances the toughness of steel, making it more resistant to impact and wear. Chromium also improves the corrosion resistance of steel, making it more suitable for use in harsh environments. Manganese improves the cold and hot working properties of steel, making it easier to process and form. Precise alloy composition adjustment can reduce energy consumption and waste emissions during the smelting process, reducing environmental pollution and improving the quality and performance of steel products. Ferrochrome and ferromanganese are renewable resources, and their use helps promote the sustainable development of the steel industry.

[0063] S8. Final Deoxidation: The molten steel temperature is 1485 ℃, and a deoxidizer is added to the ladle for final deoxidation. Argon gas is blown in during the process, and the molten steel is tapped after the steel composition sample passes the test.

[0064] It should be noted that, similar to other embodiments, step S8, final deoxidation, ensures sufficient reaction between the deoxidizer and oxygen in the molten steel, improving deoxidation efficiency. The selection of a specific temperature ensures the smooth progress of the deoxidation reaction while avoiding excessive burn-off of the deoxidizer due to overheating. Adding the deoxidizer to the ladle ensures sufficient contact between the deoxidizer and the molten steel, enhancing the deoxidation effect. Injecting argon gas not only stirs the molten steel, allowing the deoxidizer and alloying materials to be more evenly distributed, improving deoxidation and alloying efficiency, but also protects the molten steel from contamination by harmful gases such as oxygen and nitrogen in the air, further purifying the steel. Steel composition testing during the final deoxidation process allows for timely understanding of the steel's composition and enables necessary adjustments based on the test results. Final deoxidation and argon blowing effectively remove gases and inclusions from the molten steel, improving its purity and density, mechanical properties, and processing performance, thereby increasing product lifespan and reliability. Efficient final deoxidation and argon blowing shorten the smelting cycle and improve smelting efficiency. Precise temperature control and efficient utilization of the deoxidizer during the final deoxidation process help reduce energy waste and deoxidizer consumption. Simultaneously, argon blowing can also reduce energy consumption during the smelting process, achieving the goal of energy conservation and emission reduction. Through efficient final deoxidation and argon blowing, waste gas emissions during the smelting process can be reduced, thus lowering environmental pollution.

[0065] In the above embodiments, preferably: the deoxidizer in step S8 is a silicon-barium-calcium composite deoxidizer, and the amount added is 10 kg; the argon blowing pressure in step S8 is 0.05 MPa.

[0066] It should be noted that, similar to other embodiments, the silicon, barium, and calcium elements in the silicon-barium-calcium composite deoxidizer in step S8 can chemically react with oxygen in the molten steel to generate oxide impurities, thereby achieving deoxidation. These elements have a strong affinity for oxygen, resulting in high deoxidation efficiency. The silicon-barium-calcium composite deoxidizer not only removes oxygen from the molten steel but also improves the machinability and corrosion resistance of the steel. This is because the oxide impurities generated during deoxidation can act as heterogeneous nucleation sites, refining the steel grains and thus improving the mechanical and processing properties of the steel. Simultaneously, elements such as silicon, barium, and calcium can also improve the purity and density of the steel, reducing inclusions and bubbles, further improving the quality of the steel. The use of the silicon-barium-calcium composite deoxidizer can reduce the consumption of other deoxidizers and alloy materials, thereby lowering production costs. Due to its high deoxidation efficiency, it can reduce the number of adjustments and time required during the smelting process, improving smelting efficiency and further reducing production costs. A specific argon blowing pressure can both generate sufficient movement between the molten steel and slag, improving the kinetic conditions of the metallurgical reaction, and prevent molten steel from splashing and energy loss due to excessive stirring. This moderate stirring can promote the uniform distribution of deoxidizers and alloying materials in the molten steel, improving the efficiency of deoxidation and alloying.

[0067] S9, LF Refining: After tapping, the argon blowing pipe is removed and hoisted into the LF refining station. During LF refining, argon gas is re-blown. In the above embodiment, preferably, the argon blowing pressure in step S9 is 0.2 MPa and the blowing time is 5 min. In the above embodiment, further, during LF refining in step S9, lime, fluorite, and deoxidizer are added according to the slag condition, so that the slag amount is 2% of the molten steel amount. During LF refining, samples are taken and the content of each alloying element in the molten steel is adjusted according to the sample results, so that Mn: 11.0% and Cr: 1.5%.

[0068] It should be noted that, similar to other embodiments, in step S9, the LF refining furnace enhances the thermodynamic and kinetic conditions of the metallurgical reaction through methods such as electric arc heating, a reducing atmosphere within the furnace, white slag refining, and gas stirring. This allows the molten steel to achieve refining effects such as deoxidation, desulfurization, alloying, and temperature increase in a short time, ensuring accurate steel composition, uniform temperature, and sufficient flotation and purification of inclusions. The LF refining furnace employs a deoxidation method combining precipitation and diffusion, resulting in high deoxidation efficiency and effectively reducing the oxygen content in the molten steel. It also has strong desulfurization capabilities; by controlling the composition and basicity of the refining slag, and through the strong stirring effect of bottom-blown argon, the desulfurization effect can be significantly improved. Argon blowing and stirring can accelerate the uniformity of temperature and composition in the molten steel, enabling rapid and precise adjustment of complex chemical compositions, which is beneficial for removing inclusions, especially for the flotation and removal of Al2O3 inclusions.

[0069] Similarly, adding lime during LF refining increases the calcium oxide content in the slag, thereby increasing its basicity. High-basicity slag is beneficial for desulfurization because the sulfur distribution coefficient increases with slag basicity. The addition of fluorite lowers the slag's melting point and improves its fluidity. Good fluidity facilitates sufficient contact between the slag and steel interface, accelerating the metallurgical reaction. Controlling the slag quantity ensures sufficient slag to absorb inclusions and desulfurization products during refining, while avoiding unnecessary energy consumption and prolonged smelting time due to excessive slag. Precise slag quantity control helps shorten the refining cycle and improve production efficiency. By precisely controlling the slag quantity, the consumption of raw materials such as lime, fluorite, and deoxidizers can be reduced, thereby lowering production costs.

[0070] S10. Casting: After the molten steel temperature is 1450 ℃ and the chemical composition of the molten steel is qualified, the argon gas pipe is removed and the steel is hoisted into the casting station to be cast into shape, thus obtaining the required high manganese steel fork.

[0071] It should be noted that, similar to other embodiments, the precise temperature control of molten steel in step S10 results in better fluidity, which facilitates uniform filling of the mold during casting and reduces casting defects such as cold shuts and porosity. Precise temperature control during casting also prevents oxidation of the molten steel.

[0072] Example 2: A method for producing low-phosphorus, clean, high-manganese steel frogs specifically includes the following steps: S1. Melting: Before feeding scrap steel into the electric arc furnace, add 140kg of lime, 50kg of fluorite, 30kg of limestone and 15kg of iron ore to the bottom of the furnace and spread them evenly. Then add 9t of scrap steel, turn on the power to smelt and enter the melting period, during which slag removal operation is carried out.

[0073] S2. Assisted melting: When the scrap steel is 60% melted, the power is turned off and 30 kg of lime is added. Then the power is turned on for smelting and oxygen is blown to assist melting.

[0074] In the above embodiment, the 30 kg of lime added in step S2 is replaced by 60 kg of limestone; the oxygen blowing pressure in step S2 is 0.65 MPa.

[0075] S3. Making oxidation slag: After the furnace charge is melted and cleared, add 75 kg of lime, 50 kg of fluorite, 40 kg of limestone and 100 kg of iron ore to make oxidation slag. Then, turn on the electric smelting to enter the oxidation period. The entire process is slag flow operation.

[0076] In the above embodiments, preferably: in step S3, the amount of slag is maintained at 2.5% of the amount of molten steel, and slag is added in a timely manner when the amount of slag is insufficient.

[0077] S4. Oxygen Decarburization: After slag formation, oxygen decarburization begins when the molten pool temperature reaches ≥1560 ℃; the oxygen decarburization rate is 0.015% per minute, the total decarburization amount is ≥0.40%, and net boiling is maintained for more than 5 minutes; when the carbon content of the molten steel reaches within the range of 0.15%, oxidation is stopped, and the oxidation endpoint is C≤0.2% and P≤0.005%.

[0078] In the above embodiments, preferably: during step S4 oxygen blowing decarburization, the oxygen blowing pipe is inserted into a shallow blowing pool 100 mm below the surface of the molten steel at a 30° angle, the shallow blowing time is ≤3 min, and the oxygen blowing pressure is 0.7 MPa.

[0079] S5. Remove slag: When the oxidation endpoint C≤0.2% and P≤0.005%, power off the machine and remove all the slag.

[0080] S6. Making reducing slag: Add 100 kg of lime and 50 kg of fluorite to make reducing slag, and add carbon powder and silicon carbide powder as reducing agents; the amount of carbon powder added is 5 kg per ton of molten steel, and the amount of silicon carbide powder added is 4 kg per ton of molten steel. Then, turn on the electric smelting to enter the reduction period.

[0081] S7. Pre-deoxidation: Add silicon manganese alloy for pre-deoxidation. The amount of silicon manganese alloy added is 10 kg per ton of molten steel.

[0082] In the above embodiments, further: after pre-deoxidation in step S7, ferrochrome and ferromanganese are added to adjust the alloy composition in the molten steel according to the sample results.

[0083] S8. Final Deoxidation: The molten steel temperature is 1490 ℃, and a deoxidizer is added to the ladle for final deoxidation. Argon gas is blown in during the process, and the molten steel is tapped after the steel composition sample passes the test.

[0084] In the above embodiments, preferably: the deoxidizer in step S8 is a silicon-barium-calcium composite deoxidizer, and the amount added is 15 kg; the argon blowing pressure in step S8 is 0.015 MPa.

[0085] S9, LF Refining: After tapping, remove the argon blowing pipe and hoist it into the LF refining station. During LF refining, argon gas is blown in again. During LF refining, samples are taken and the content of each alloying element in the molten steel is adjusted according to the sample results to make Mn: 12.0% and Cr: 2.0%.

[0086] In the above embodiments, preferably, the argon blowing pressure in step S9 is 0.25 MPa and the argon blowing time is 8 min.

[0087] In the above embodiments, further: during LF refining in step S9, lime, fluorite and deoxidizer are added according to the slag condition, so that the amount of slag is 3% of the amount of molten steel.

[0088] S10. Casting: After the molten steel temperature is 1460 ℃ and the chemical composition of the molten steel is qualified, the argon gas pipe is removed and the steel is hoisted into the casting station to be cast into shape, thus obtaining the required high manganese steel fork.

[0089] The principles and technical effects of each step in this embodiment have been explained in Embodiment 1 and will not be repeated here.

[0090] Example 3: A method for producing low-phosphorus, clean, high-manganese steel frogs specifically includes the following steps: S1. Melting: Before feeding scrap steel into the electric arc furnace, add 160 kg of lime, 70 kg of fluorite, 40 kg of limestone and 20 kg of iron ore to the bottom of the furnace and spread them evenly. Then add 10 t of scrap steel, turn on the power to smelt and enter the melting period, during which slag removal operation is carried out.

[0091] S2. Assisted melting: When the scrap steel is 60% melted, the power is turned off and 60 kg of lime is added. Then the power is turned on for smelting and oxygen is blown to assist melting.

[0092] In the above embodiment, the 60 kg of lime added in step S2 is replaced by 80 kg of limestone; the oxygen blowing pressure in step S2 is 0.8 MPa.

[0093] S3. Making oxidation slag: After the furnace charge is melted and cleared, add 80 kg of lime, 60 kg of fluorite, 45 kg of limestone and 120 kg of iron ore to make oxidation slag. Then, turn on the electric smelting to enter the oxidation period. The entire process is slag flow operation.

[0094] In the above embodiments, preferably: in step S3, the amount of slag is maintained at 3% of the amount of molten steel, and slag is added in a timely manner when the amount of slag is insufficient.

[0095] S4. Oxygen Decarburization: After slag formation, oxygen decarburization begins when the molten pool temperature reaches ≥1560 ℃; the oxygen decarburization rate is 0.02% per minute, the total decarburization amount is ≥0.40%, and net boiling is maintained for more than 5 minutes; when the carbon content of the molten steel reaches within the range of 0.20%, oxidation is stopped, and the oxidation endpoint is C≤0.2% and P≤0.005%.

[0096] In the above embodiments, preferably: during step S4 oxygen blowing decarburization, the oxygen blowing pipe is inserted into a shallow blowing pool 200 mm below the surface of the molten steel at a 30° angle, the shallow blowing time is ≤3 min, and the oxygen blowing pressure is 0.8 MPa.

[0097] S5. Remove slag: When the oxidation endpoint C≤0.2% and P≤0.005%, power off the machine and remove all the slag.

[0098] S6. Making reducing slag: Add 120 kg of lime and 70 kg of fluorite to make reducing slag, and add carbon powder and silicon carbide powder as reducing agents; the amount of carbon powder added is 6 kg per ton of molten steel, and the amount of silicon carbide powder added is 5 kg per ton of molten steel. Then, turn on the electric smelting to enter the reduction period.

[0099] S7. Pre-deoxidation: Add silicon-manganese alloy for pre-deoxidation. The amount of silicon-manganese alloy added is 15 kg per ton of molten steel.

[0100] In the above embodiments, further: after pre-deoxidation in step S7, ferrochrome and ferromanganese are added to adjust the alloy composition in the molten steel according to the sample results.

[0101] S8. Final Deoxidation: The molten steel temperature is 1500 ℃, and a deoxidizer is added to the ladle for final deoxidation. Argon gas is blown in during the process, and the molten steel is tapped after the steel composition sample passes the test.

[0102] In the above embodiments, preferably: the deoxidizer in step S8 is a silicon-barium-calcium composite deoxidizer, and the amount added is 20 kg; the argon blowing pressure in step S8 is 0.2 MPa.

[0103] S9, LF Refining: After tapping, remove the argon blowing pipe and hoist it into the LF refining station. During LF refining, argon gas is blown in again. During LF refining, samples are taken and the content of each alloying element in the molten steel is adjusted according to the sample results to make Mn: 13.0% and Cr: 2.5%.

[0104] In the above embodiments, preferably, the argon blowing pressure in step S9 is 0.3 MPa and the argon blowing time is 10 min.

[0105] In the above embodiments, further: during LF refining in step S9, lime, fluorite and deoxidizer are added according to the slag condition, so that the amount of slag is 4% of the amount of molten steel.

[0106] S10. Casting: After the molten steel reaches a temperature of 1465 ℃ and its chemical composition is tested and found to be qualified, the argon gas pipe is removed and the steel is hoisted into the casting station for casting to obtain the required high-manganese steel turnout. Similarly, the principles and technical effects of each step in this embodiment have been described in Embodiment 1 and will not be repeated here.

[0107] An application of a low-phosphorus clean high-manganese steel frog, which is used in heavy-haul railways.

[0108] As can be seen from the above description, step S1 of the present invention lowers the melting point of slag, accelerates the melting of scrap steel, removes phosphorus, shortens the smelting cycle, improves production efficiency, reduces costs, and reduces pollution.

[0109] In step S2 of this invention, the slag basicity is adjusted, which is more conducive to the removal of harmful elements such as phosphorus and sulfur; oxygen blowing assists melting and rapidly increases the furnace temperature, improves smelting efficiency, and enhances steel quality; limestone replaces lime, which is inexpensive and reduces costs; limestone decomposes to produce calcium oxide, which plays a role in slag formation and dephosphorization, while the carbon dioxide gas produced by limestone decomposition increases the electric arc thermal efficiency and promotes the smelting reaction.

[0110] In step S3 of this invention, the slag viscosity is adjusted to facilitate slag fluidity and metallurgical reaction, thereby reducing energy consumption. Iron ore acts as an oxidant, enhancing the oxidizing properties of the slag, forming a stable oxidized slag, removing harmful impurities, and improving the purity and quality of molten steel.

[0111] The present invention provides a stable decarburization rate in step S4, which precisely controls the carbon content in the molten steel to meet the requirements of subsequent smelting and casting processes; molten pool temperature control ensures sufficient slag formation, providing sufficient heat for the decarburization reaction; precise control of oxygen blowing time and rate achieves precise control of the carbon content in the molten steel; oxidation endpoint control ensures that the carbon and phosphorus content in the molten steel remains stable within the target range, meeting the requirements for high-quality products; oxygen blowing decarburization, with sufficient reaction between slag and molten steel, helps remove impurity elements from the molten steel, improving the purity and uniformity of the steel.

[0112] In step S5 of this invention, all slag is removed, which improves the purity and quality of molten steel, avoids secondary pollution, prevents chemical damage to equipment, prevents slag accumulation from clogging the tap or slag discharge port of the electric arc furnace, reduces the emission of smelting waste from the electric arc furnace, and enables the recovery and utilization of useful components from the slag. The slag removal operation is simple and convenient, and the operation during power outages ensures personnel safety.

[0113] In step S6 of this invention, oxides in molten steel are reduced to metallic elements, improving purity and quality. Carbon powder and silicon carbide powder act as reducing agents to accelerate the reduction reaction of oxides. The reduction dosage and smelting time are precisely controlled to ensure that oxides are fully reduced and to avoid excessive reduction that could lead to a decline in the quality of molten steel. Compared with traditional smelting methods, this invention reduces environmental pollution, energy consumption, operational difficulty, and cost, while improving efficiency and operational safety.

[0114] In step S7 of this invention, both manganese and silicon in the silicon-manganese alloy can react with oxygen in molten steel to form oxides, thus removing excess oxygen. Compared with other deoxidizers, the silicon-manganese alloy has a higher deoxidation efficiency. The silicon-manganese alloy is not only a deoxidizer but also an important alloying additive that can adjust the chemical composition of steel and improve its mechanical and processing properties.

[0115] The final deoxidation step S8 and the selection of a specific temperature in this invention ensure the smooth progress of the deoxidation reaction while avoiding excessive burning of the deoxidizer due to excessively high temperatures. The introduction of argon to stir the molten steel saves energy and reduces consumption while protecting the molten steel from pollution by harmful gases such as oxygen and nitrogen in the air, thus purifying the steel. Precise temperature control and effective utilization of the deoxidizer reduce energy waste and deoxidizer consumption, thereby reducing environmental pollution. The silicon-barium-calcium composite deoxidizer, with silicon, barium, and calcium elements, can chemically react with oxygen in the molten steel to generate oxide impurities, achieving efficient deoxidation and improving the machinability and corrosion resistance of the steel. The generated oxide impurities can act as heterogeneous nucleation sites, refining the steel grains, improving the mechanical and processing properties of the steel, and increasing the purity and density of the steel.

[0116] The LF refining in step S9 of this invention achieves refining effects such as deoxidation, desulfurization, alloying, and heating in a short time. By controlling the composition and basicity of the refining slag and the strong stirring effect of bottom-blown argon, the desulfurization effect is significantly improved, especially the removal of inclusions such as Al2O3. The addition of fluorite improves the slag fluidity by lowering the slag melting point, which helps to fully contact the slag-steel interface and accelerates the metallurgical reaction.

[0117] In summary, this invention employs a rational slag design to reduce the phosphorus content in high-manganese steel, effectively solving the problem of excessively high phosphorus content leading to substandard product composition in high-manganese steel produced using existing technologies. By blowing air into the molten steel, the aim is to clean the steel, maximizing the removal of inclusions and extending the service life of the high-manganese steel. LF refining removes sulfur, oxygen, nitrogen, and inclusions, improving finished product quality and extending service life.

[0118] It should be understood that although this specification is mainly described according to one embodiment, it does not mean that the embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in this embodiment can also be appropriately arranged and combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A low-phosphorus, clean, high-manganese steel frog, characterized in that, By mass percentage, it includes the following components: C: 1.1-1.3%, Mn: 11.0-13.0%, Si≤0.5%, P≤0.03%, S≤0.02%, Cr: 1.5-2.5%, N: 0.02-0.05%, balance being Fe and unavoidable impurities.

2. A method for producing a low-phosphorus, clean, high-manganese steel frog, characterized in that: The production of the turnout as described in claim 1, involving dynamic adjustment of slag composition in stages during low-temperature dephosphorization and production via bottom blowing argon combined with LF refining in the ladle, includes the following steps: S1. Melting: Before feeding scrap steel into the electric arc furnace, add 120-160 kg of lime, 30-70 kg of fluorite, 20-40 kg of limestone and 10-20 kg of iron ore to the bottom of the furnace and spread them evenly. Then add 8-10 t of scrap steel, turn on the power to smelt and enter the melting period, during which slag removal operation is carried out. S2. Assisted melting: When the scrap steel is 60% melted, the power is turned off and 20-60 kg of lime is added. Then the power is turned on for smelting and oxygen is blown to assist melting. S3. Making oxidation slag: After the furnace charge is melted and cleared, add 70-80 kg of lime, 40-60 kg of fluorite, 30-45 kg of limestone and 80-120 kg of iron ore to make oxidation slag. Then, turn on the electric smelting to enter the oxidation period. The entire process is slag flow operation. S4. Oxygen Decarburization: After slag formation, oxygen decarburization begins when the molten pool temperature reaches ≥1560 ℃; the oxygen decarburization rate is 0.01~0.02% per minute, the total decarburization amount is ≥0.40%, and net boiling is maintained for more than 5 minutes; when the carbon content of the molten steel reaches the range of 0.10~0.20%, oxidation is stopped, and the oxidation endpoint is C≤0.2% and P≤0.005%; S5. Slag Removal: When the oxidation endpoint C≤0.2% and P≤0.005%, power should be cut off and all slag should be removed. S6. Making reducing slag: Add 80-120 kg of lime and 30-70 kg of fluorite to make reducing slag, and add carbon powder and silicon carbide powder as reducing agents; the amount of carbon powder added is 3-6 kg per ton of molten steel, and the amount of silicon carbide powder added is 2-5 kg ​​per ton of molten steel. Then, turn on the electric smelting to enter the reduction period. S7. Pre-deoxidation: Add silicon-manganese alloy for pre-deoxidation. The amount of silicon-manganese alloy added is 5-15 kg per ton of molten steel. S8. Final deoxidation: The temperature of the molten steel is 1485~1500 ℃, and a deoxidizer is added to the ladle for final deoxidation. Argon gas is blown in during the process, and the steel is tapped after the steel composition sample is qualified. S9, LF Refining: After tapping, the argon blowing pipe is removed and the steel is hoisted into the LF refining station. During LF refining, argon gas is reintroduced. During LF refining, samples are taken and the content of each alloying element in the molten steel is adjusted according to the sample results to achieve Mn: 11.0~13.0% and Cr: 1.5~2.5%. S10. Casting: After the molten steel temperature is 1450~1465 ℃ and the chemical composition of the molten steel is qualified, the argon gas pipe is removed and the steel is hoisted into the casting station for casting to obtain the required high manganese steel turnout.

3. The production method according to claim 2, characterized in that: The 20-60 kg of lime added in step S2 is replaced with 40-80 kg of limestone; the oxygen blowing pressure is 0.5-0.8 MPa.

4. The production method according to claim 2, characterized in that: Step S3: Maintain the slag amount at 2-3% of the molten steel amount, and add slag in a timely manner if the slag amount is insufficient.

5. The production method according to claim 2, characterized in that: In step S4, during oxygen blowing decarburization, the oxygen blowing pipe is tilted at 30° and inserted into a shallow blowing pool 50-200 mm below the surface of the molten steel. The shallow blowing time is ≤3 min, and the oxygen blowing pressure is 0.5-0.8 MPa.

6. The production method according to claim 2, characterized in that: After pre-deoxidation in step S7, ferrochrome and ferromanganese are added to adjust the alloy composition in the molten steel based on the sample results.

7. The production method according to claim 2, characterized in that: In step S8, the deoxidizer is a silicon-barium-calcium composite deoxidizer, and the amount added is 10-20 kg; the argon blowing pressure in step S8 is 0.05-0.2 MPa.

8. The production method according to claim 2, characterized in that: In step S9, the argon blowing pressure is 0.2–0.3 MPa, and the argon blowing time is 5–10 min.

9. The production method according to claim 2 or 8, characterized in that: During LF refining in step S9, lime, fluorite, and deoxidizer are added according to the slag condition, so that the amount of slag is 2 to 4% of the amount of molten steel.

10. The application of a low-phosphorus clean high-manganese steel frog as described in claim 1, or a low-phosphorus clean high-manganese steel frog produced by any of the production methods described in claims 2-9, characterized in that: The low-phosphorus, clean, high-manganese steel frogs are used in heavy-haul railways.

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