High-efficiency smelting method for semiconductor ultra-pure steel capable of accurately regulating and controlling components

Abstract

The invention relates to an efficient smelting method for semiconductor ultra-pure steel capable of accurately regulating and controlling components, and belongs to the technical field of ultra-pure steel. The method comprises the operation steps of molten iron desulphurization, converter blowing, converter tapping, refining and protective casting. The converter tapping needs to be quenched, and the semiconductor ultra-pure steel is obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of ultra-pure steel, and in particular to an efficient smelting method for semiconductor ultra-pure steel with precisely controlled composition. Background Art

[0002] Pure steel, also known as high manganese steel, is a high-performance steel made through a refining process. It not only has strict requirements on the quantity and size of non-metallic inclusions in the steel, but also has extremely limited content of other impurity elements in the steel. Due to its excellent hardness, toughness and anti-wear ability, this kind of steel has a wide range of applications in multiple fields.

[0003] Chinese Patent CN102181656B: It relates to a method for smelting high-purity steel in a vacuum induction furnace, and its steps are as follows: update the vacuum pump oil; preheat the diffusion pump; put the industrial pure iron and carbon particles to be smelted into a CaO crucible tilted to one side; start pumping after the diffusion pump is preheated for 35 minutes; when the vacuum degree reaches 266 Pa, start the Roots pump and energize the induction coil with a power of 10 kW; when the vacuum degree reaches ≤15 Pa, start the diffusion pump and adjust the power to 20 kW; gradually increase the power to 60 kW; 10 minutes after the iron is melted, adjust the power to 50 kW, turn off the diffusion pump, and at the same time add ferrosilicon to the crucible; after 10 minutes, turn off the Roots pump and the mechanical pump, and at the same time fill with argon; after 2 minutes, add Mn steel; after 2 minutes, cut off the power supply of the induction coil; after standing for 3 minutes, tap the steel.

[0004] Chinese Patent CN103924030B: It relates to the smelting field, specifically to a smelting method for ultra-low oxygen pure steel. Use a vacuum electric furnace or a vacuum induction furnace for smelting and vacuum casting, and the required vacuum degree is 0.05 - 100 Pa; after the metal charge is melted, keep the metal liquid boiling under vacuum for 5 - 30 min, reduce the oxygen content through the vacuum carbon-oxygen reaction, and do not add any deoxidizer or deoxidized steel. After tempering, stand for 20 - 30 min, and keep the metal liquid boiling under vacuum for 5 - 30 min. When the oxygen content is below 10 ppm, add 0.5 - 3 kg / t of Si-Ca-Al-Mkg-RE composite deoxidizer, and after adding, stand for 1 - 10 min for vacuum casting to obtain pure steel with a total oxygen content below 4 ppm.

[0005] Chinese Patent CN109023077B: Disclosed is 09MnNiD high-purity steel for low temperature use, characterized in that: the weight percentages of the chemical components of the high-purity steel are: C: 0.03 - 0.12%, Si: 0.20 - 0.75%, Mn: 0.3 - 2.4%, P: ≤0.01%, S: ≤0.01%, Ni: 0.05 - 0.8%, Nb: 0.04 - 0.15%, Als: 0.005 - 0.012%, V: 0.002 - 0.015%, and the rest is Fe. The weight percentage content of Mn in the high-purity steel / the weight percentage content of C is 10 - 20.

[0006] For the pure steel prepared by the above patents and the prior art, there are problems such as long process flow, unstable molten steel quality, low desulfurization efficiency, high energy consumption, and high cost. Summary of the Invention

[0007] To solve the above problems, the present invention provides a highly efficient smelting method for semiconductor ultra-pure steel with precisely controlled composition, and the weight percentages of its chemical components are as follows:

[0008] C: 0.004 - 0.007%;

[0009] Si: 0.10 - 0.14%;

[0010] Mn: 0.035 - 0.045%;

[0011] P: ≤0.008%;

[0012] S: ≤0.0008%;

[0013] Ni: 14.6 - 14.9%;

[0014] Cr: 16.6 - 16.9%;

[0015] Mo: 2.3 - 2.4%;

[0016] Cu: 0.12 - 0.18%;

[0017] Al: 0.005 - 0.007%;

[0018] Nb: 0.009 - 0.011%;

[0019] Ti: 0.009 - 0.011%;

[0020] Se: 0.009 - 0.011%;

[0021] Ca: 0.009 - 0.011%;

[0022] O: 8 - 12 ppm;

[0023] H: 0.5 - 1.5 ppm;

[0024] N: 60 - 70 ppm; the balance is iron:

[0025] Its operating steps include: hot metal desulfurization, converter blowing, converter tapping, refining, and protected casting;

[0026] The converter tapping needs to be quenched to obtain semiconductor ultra-pure steel;

[0027] During the quenching treatment, a quenching agent is required, and the quenching agent is prepared by reacting boralkyl polyether, sodium chloride, sodium dodecyl sulfate, sodium benzoate, sodium molybdate, defoaming agent and water.

[0028] Further, the hot metal desulfurization is carried out by top spraying desulfurization on the mixer car; the addition amount of the desulfurizing agent is 4-6 kg / ton of molten steel, and the nitrogen flow rate is 450-550 m 3 / h; the desulfurizing agent composition is 30-40% calcium carbide, 25-30% calcium oxide, and the rest is calcium carbonate.

[0029] Further, the process of converter blowing is as follows:

[0030] Charging preparation: Check the lining condition of the converter to ensure that the lining is not severely eroded or damaged. Pour the desulfurized hot metal into the converter;

[0031] Bottom blowing gas control: Adopt the switching mode of nitrogen and argon for bottom blowing, switch every 10 minutes, and the blowing flow rate is 450-550 Nm 3 / h. When switching gases, ensure the normal operation of the gas switching device to avoid gas leakage or untimely switching. Through the stirring action of the bottom blowing gas, promote the homogenization of the composition and temperature of the molten steel, and at the same time facilitate the removal of impurities.

[0032] Temperature and basicity control: During the blowing process, closely monitor the temperature of the molten bath. By adjusting the oxygen flow rate and blowing time, control the temperature of the molten bath at 1450-1550 °C. At the same time, control the slag basicity CaO / SiO2 at 2.5-3.0, and adjust the slag composition by adding slag-making agents such as lime and dolomite. When the slag basicity deviates from the target range, timely adjust the addition amount of the slag-making agent. In addition, in the later stage of blowing, according to the carbon content and temperature of the molten steel, reasonably control the stopping blowing temperature to keep it at 1650-1680 °C.

[0033] Further, during the tapping process of the converter, argon stirring is carried out throughout the process; before and after tapping, slag blocking is carried out to control the amount of slag flowing down, ensuring that the thickness of the ladle slag is 50-80 mm; when 1 / 3 of the steel is tapped, add 400-500 kg / ton of molten steel of lime and 100-200 kg / ton of molten steel of composite refining slag for slag washing; then through quenching treatment, semiconductor ultra-pure steel is obtained.

[0034] Further, during the refining process, the operation of making white slag is carried out, the quaternary basicity of the slag is controlled at 2-3, the refining tapping temperature is controlled at 1500-1600 °C, and the refining time is 30-60 minutes.

[0035] Further, the quenching treatment is as follows:

[0036] S1 Pretreatment: Clean the surface of the steel code, remove oil stains, and preheat it to 600 - 700 °C to remove internal stress;

[0037] S2 Quenching preparation: Prepare a quenching agent with a certain concentration, and check the quenching equipment to ensure normal operation;

[0038] S3 Austenitization: Heat the pretreated steel code to 1000 - 1080 °C and hold for a certain time to completely transform the internal structure into austenite;

[0039] S4 Quenching execution: Quench the austenitized steel code rapidly into the quenching liquid, controlling the stirring speed and the temperature of the quenching liquid;

[0040] S5 Post-treatment: After quenching, clean and dry the steel code, and perform tempering treatment to eliminate quenching stress;

[0041] S6 Quality inspection: Include hardness testing and metallographic analysis to confirm that the quenched steel code meets the standards;

[0042] The quenching liquid is obtained by mixing the quenching agent with water, where the volume ratio concentration range of the quenching agent is 5 - 15% to ensure rapid and uniform cooling of the steel code during quenching.

[0043] Furthermore, the preparation method of the quenching agent is as follows:

[0044] By mass percentage:

[0045] Borane polyether 8 - 12%; Main film-forming agent, controlling the cooling rate and reducing quenching deformation. Sodium chloride 0.5 - 3%; Improving solution conductivity, accelerating the rupture of the steam film, and enhancing the cooling capacity. Sodium dodecyl sulfate 0.1 - 0.5%; Surfactant, improving wettability and cooling uniformity. Sodium benzoate 0.3 - 0.8%; Rust inhibitor, inhibiting metal corrosion.

[0046] Sodium molybdate 0.1 - 0.3%; Synergistic rust prevention, improving high-temperature oxidation resistance.

[0047] Defoamer 0.05 - 0.1%; Eliminating foam and ensuring the stability of the quenching process.

[0048] The balance is deionized water;

[0049] Furthermore, the preparation method of the borane polyether is as follows:

[0050] 5-10 parts by weight of methyl allyl alcohol polyether and 100-200 parts by weight of ethylene dichloride are added to a reaction kettle 1, and stirred for 50-100 minutes at a temperature of 70-80° C.; then 0.2-0.5 parts of disodium mercapto dodecaborane, 0.03-0.2 parts by weight of 3-mercaptoquinoline and 0.5-2 parts by weight of triethylamine are added, and stirring is continued for 50-100 minutes at the same temperature; thereafter, the ethylene dichloride is removed by distillation to obtain a borane polyether.

[0051] The methyl allyl alcohol polyether has a molecular weight of 500-1000.

[0052] Reaction mechanism

[0053] First, at the reaction temperature (70-80°C), the hydrogen atoms on the thiol group in the 3-mercaptoquinoline molecule are homolytically split to generate thiol free radicals. The generated thiol free radicals add to the allyl group in the methyl allyl alcohol polyether, breaking the π bond of the allyl double bond to form a new carbon-sulfur bond and a carbon free radical.

[0054] The new carbon radical takes hydrogen atoms from disodium thiol dodecaborane to form a stable product and regenerate thiol radicals, allowing the reaction to continue. As the reaction proceeds, the free radicals combine with each other, such as two thiol radicals combining to form disulfide, and the reaction terminates.

[0055] The main function of high purity stainless steel quenching agent

[0056] 1. Borane polyether has good thermal conductivity. It can quickly take away the heat from the steel surface during quenching, transform the stainless steel structure, form fine and uniform grains, improve hardness and strength, and its cooling rate can be accurately controlled by adjusting parameters such as concentration and temperature to avoid defects such as cracks and deformation.

[0057] Borane polyether can form a protective film on the surface of stainless steel to prevent rust, which is critical for high-purity stainless steel. At the same time, it can act as a lubricant during quenching, reduce friction between steel and equipment, reduce surface wear, and improve surface quality.

[0058] 2. Corrosion inhibition of quinoline group: Quinoline and its derivatives are widely used in industrial production due to their excellent corrosion inhibition performance. The nitrogen atom in the quinoline group can form a coordination bond with the metal surface, thereby forming a stable protective layer on the metal surface. This protective layer can not only prevent the metal from further oxidation, but also inhibit the dissolution of metal ions to a certain extent, thereby maintaining the high hardness and good tensile properties of the metal.

[0059] 3. Enhancement of intermolecular forces: During the quenching process, the borane and quinoline groups interact with the atoms on the metal surface through intermolecular forces (such as hydrogen bonds, van der Waals forces, etc.) to form a more stable chemical film. DETAILED DESCRIPTION

[0060] To further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description in combination with examples and comparative examples:

[0061] Mechanical property determination of ultra-pure steel: Detection was carried out with reference to kgB / T288.1-2021, and the detection results are shown in Table 1.

[0062] Example 1

[0063] An efficient smelting method for semiconductor ultra-pure steel with precisely controlled components, the weight percentages of its chemical components are as follows:

[0064] C: 0.004%;

[0065] Si: 0.10%;

[0066] Mn: 0.035%;

[0067] P: ≤0.008%;

[0068] S: ≤0.0008%;

[0069] Ni: 14.6%;

[0070] Cr: 16.6%;

[0071] Mo: 2.3%;

[0072] Cu: 0.12%;

[0073] Al: 0.005%;

[0074] Nb: 0.009%;

[0075] Ti: 0.009%;

[0076] Se: 0.009%;

[0077] Ca: 0.009%;

[0078] O: 8ppm;

[0079] H: 0.5ppm;

[0080] N: 60ppm; the balance is iron:

[0081] Its operation steps include: hot metal desulfurization, converter blowing, converter tapping, refining, and protected casting.

[0082] The above-mentioned hot metal desulfurization adopts top spraying desulfurization on the hot metal mixer; the addition amount of desulfurizer is 4 kg / ton of molten steel, and the nitrogen flow rate is 450 m 3 / h; The desulfurizer composition is 30% calcium carbide, 25% calcium oxide, and the rest is calcium carbonate.

[0083] The process of converter blowing is as follows:

[0084] Charging preparation: Check the lining condition of the converter to ensure that the lining has no serious erosion or damage. Pour the desulfurized hot metal into the converter;

[0085] Bottom blowing gas control: Adopt the switching mode of nitrogen and argon for bottom blowing, switch every 10 min, and the blowing flow rate is 450 Nm 3 / h. When switching gases, ensure the normal operation of the gas switching device to avoid gas leakage or untimely switching. Through the stirring action of the bottom blowing gas, promote the homogenization of the molten steel composition and temperature, and at the same time facilitate the removal of impurities.

[0086] Temperature and basicity control: During the blowing process, closely monitor the molten bath temperature, and control the molten bath temperature at 1450 °C by adjusting the oxygen flow rate and blowing time. At the same time, control the slag basicity CaO / SiO2 at 2.5, and adjust the slag composition by adding slag-making agents such as lime and dolomite. When the slag basicity deviates from the target range, timely adjust the addition amount of the slag-making agent. In addition, in the later stage of blowing, according to the carbon content and temperature of the molten steel, reasonably control the tapping temperature to keep it at 1650 °C.

[0087] During the tapping process of the converter, argon stirring is carried out throughout the process; slag blocking is carried out before and after tapping to control the slag volume entering the ladle and ensure that the ladle slag thickness is 50 mm; when 1 / 3 of the steel is tapped, 400 kg of lime per ton of molten steel and 100 kg of composite refining slag per ton of molten steel are added for slag washing; then, after quenching treatment, semiconductor ultra-pure steel is obtained.

[0088] During the refining process, the operation of making white slag is carried out, the quaternary basicity of the slag is controlled at 2, the refining tapping temperature is controlled at 1500 °C, and the refining time is 30 min.

[0089] The quenching treatment is as follows:

[0090] S1 Pretreatment: Clean the surface of the steel ingot, remove the oil stain, and preheat it to 600 °C to remove the internal stress;

[0091] S2 Quenching preparation: Prepare a quenching agent with a certain concentration and check the quenching equipment to ensure normal operation;

[0092] S3 Austenitization: Heat the pretreated steel ingot to 1000 °C and keep it for a certain time to completely transform the internal structure into austenite;

[0093] S4 Quenching execution: Quench the austenitized steel ingot rapidly in the quenching liquid, and control the stirring speed and the temperature of the quenching liquid;

[0094] S5 Post-treatment: After quenching, the steel codes are cleaned, dried, and tempered to eliminate quenching stress;

[0095] S6 Quality inspection: Including hardness testing and metallographic analysis to confirm that the quenched steel codes meet the standards;

[0096] The quenching liquid is obtained by mixing the quenching agent with water, and the volume ratio concentration range of the quenching agent is 5% to ensure rapid and uniform cooling of the steel codes during quenching.

[0097] The preparation method of the quenching agent is as follows: by mass percentage:

[0098] Borane polyether: 8%; Sodium chloride: 0.5%; Sodium dodecyl sulfate 0.1%; Sodium benzoate: 0.3%; Sodium molybdate: 0.1%; Defoaming agent: 0.051%; Deionized water: the balance;

[0099] The preparation method of the borane polyether is as follows:

[0100] Add 5 kg of methyl allyl alcohol polyether and 100 kg of dichloroethane to the reaction kettle 1, stir for 50 minutes at a temperature of 70 °C; then add 0.2 kg of sodium mercaptododecaborane dianion, 0.03 kg of 3-mercaptoquinoline, and 0.5 kg of triethylamine, and continue to stir for 50 minutes at the same temperature; after that, remove dichloroethane by distillation to obtain borane polyether.

[0101] The defoaming agent is BYK-024.

[0102] The methyl allyl alcohol polyether has a molecular weight of 500.

[0103] Example 2

[0104] A high-efficiency smelting method for semiconductor ultra-pure steel with precisely controlled components, and its chemical components by weight percentage are: C: 0.006%;

[0105] Si: 0.11%;

[0106] Mn: 0.037%;

[0107] P: ≤0.008%;

[0108] S: ≤0.0008%;

[0109] Ni: 14.7%;

[0110] Cr: 16.7%;

[0111] Mo: 2.31%;

[0112] Cu: 0.15%;

[0113] Al: 0.0055%;

[0114] Nb: 0.0095%;

[0115] Ti: 0.0095%;

[0116] Se: 0.0095%;

[0117] Ca: 0.0095%;

[0118] O: 9 ppm;

[0119] H: 0.7 ppm;

[0120] N: 64 ppm; the balance is iron:

[0121] Its operation steps include: hot metal desulfurization, converter blowing, converter tapping, refining, and protected casting.

[0122] The hot metal desulfurization mentioned above adopts top injection desulfurization on the mixer car roof; the addition amount of desulfurizer is 4.3 kg per ton of molten steel, and the nitrogen flow rate is 480 m 3 / h; the desulfurizer composition is 32% calcium carbide, 27% calcium oxide, and the rest is calcium carbonate.

[0123] The process of converter blowing is as follows:

[0124] Charging preparation: Check the lining condition of the converter to ensure that the lining has no serious erosion or damage. Pour the desulfurized hot metal into the converter.

[0125] Bottom blowing gas control: Adopt the switching mode of nitrogen and argon for bottom blowing, switch every 10 min, and the blowing flow rate is 480 Nm 3 / h. When switching gases, ensure the normal operation of the gas switching device to avoid gas leakage or untimely switching. Through the stirring action of the bottom blowing gas, promote the homogenization of the composition and temperature of the molten steel, and at the same time facilitate the removal of impurities.

[0126] Temperature and alkalinity control: During the blowing process, closely monitor the temperature of the molten bath. By adjusting the oxygen flow rate and blowing time, control the temperature of the molten bath at 1470 °C. At the same time, control the slag alkalinity CaO / SiO2 at 2.7, and adjust the slag composition by adding slag-making agents such as lime and dolomite. When the slag alkalinity deviates from the target range, promptly adjust the addition amount of the slag-making agent. In addition, in the later stage of blowing, according to the carbon content and temperature of the molten steel, reasonably control the tapping temperature to keep it at 1660 °C. During the tapping process of the converter, argon stirring is carried out throughout the process; before and after tapping, slag blocking is carried out to control the amount of slag flowing into the ladle, ensuring that the thickness of the ladle slag is 60 mm; when 1 / 3 of the steel is tapped, add 440 kg of lime per ton of molten steel and 140 kg of composite refining slag per ton of molten steel for slag washing; then through quenching treatment, semiconductor ultra-pure steel is obtained.

[0127] During the refining process, white slag making operation is carried out, the quaternary alkalinity of the slag is controlled at 2, the refining tapping temperature is controlled at 1540 °C, and the refining time is 40 min.

[0128] The quenching treatment is as follows:

[0129] S1 Pretreatment: Clean the surface of the steel code, remove oil stains, and preheat it to 640 °C to remove internal stress;

[0130] S2 Quenching preparation: Prepare a quenching agent with a certain concentration, and check the quenching equipment to ensure normal operation;

[0131] S3 Austenitization: Heat the pretreated steel code to 1040 °C and hold for a certain time to completely transform the internal structure into austenite;

[0132] S4 Quenching execution: Quench the austenitized steel code rapidly into the quenching liquid, controlling the stirring speed and the temperature of the quenching liquid;

[0133] S5 Post-treatment: After quenching, clean and dry the steel code, and carry out tempering treatment to eliminate quenching stress;

[0134] S6 Quality inspection: Include hardness testing and metallographic analysis to confirm that the quenched steel code meets the standards;

[0135] The quenching liquid is obtained by mixing the quenching agent with water, and the volume ratio concentration range of the quenching agent is 8% to ensure that the steel code can be cooled rapidly and uniformly during the quenching process.

[0136] The preparation method of the quenching agent is as follows: by mass percentage:

[0137] Borane polyether: 9%; Sodium chloride: 0.8%; Sodium dodecyl sulfate 0.2%; Sodium benzoate: 0.4%; Sodium molybdate: 0.15%; Defoaming agent: 0.05 - 7%; Deionized water: the balance;

[0138] The preparation method of the boranyl polyether is as follows:

[0139] Add 6 kg of methyl allyl alcohol polyether and 120 kg of dichloroethane into the reaction kettle 1, and stir for 60 minutes under the condition of a temperature of 72 °C; then add 0.3 kg of sodium dodecaboranethiolate, 0.06 kg of 3-mercaptoquinoline, and 0.8 kg of triethylamine, and continue to stir for 70 minutes at the same temperature; afterwards, remove dichloroethane by distillation to obtain the boranyl polyether.

[0140] The defoaming agent described is BYK-025.

[0141] The methyl allyl alcohol polyether has a molecular weight of 800.

[0142] Example 3

[0143] An efficient smelting method for semiconductor ultra-pure steel with precisely controlled components, and the weight percentages of its chemical components are as follows:

[0144] C: 0.006%;

[0145] Si: 0.11%;

[0146] Mn: 0.038%;

[0147] P: ≤0.008%;

[0148] S: ≤0.0008%;

[0149] Ni: 14.7%;

[0150] Cr: 16.7%;

[0151] Mo: 2.32%;

[0152] Cu: 0.15%;

[0153] Al: 0.0055%;

[0154] Nb: 0.0097%;

[0155] Ti: 0.0097%;

[0156] Se: 0.0097%;

[0157] Ca: 0.0097%;

[0158] O: 10 ppm;

[0159] H: 1.1 ppm;

[0160] N: 66 ppm; the balance is iron:

[0161] Its operation steps include: hot metal desulfurization, converter blowing, converter tapping, refining, and protected casting.

[0162] For the hot metal desulfurization mentioned above, top spraying desulfurization on the hot metal mixer car is adopted; the addition amount of desulfurizer is 5 kg / ton of molten steel, and the nitrogen flow rate is 500 m 3 / h; the desulfurizer composition is 38% calcium carbide, 28% calcium oxide, and the rest is calcium carbonate.

[0163] The process of converter blowing is as follows:

[0164] Charging preparation: Check the lining condition of the converter to ensure that the lining has no serious erosion or damage. Pour the desulfurized hot metal into the converter.

[0165] Bottom blowing gas control: Adopt the switching mode of nitrogen and argon for bottom blowing, switch every 10 min, and the blowing flow rate is 500 Nm 3 / h. When switching gases, ensure the normal operation of the gas switching device to avoid gas leakage or untimely switching. Through the stirring effect of the bottom blowing gas, promote the uniformity of the composition and temperature of the molten steel, and at the same time facilitate the removal of impurities.

[0166] Temperature and basicity control: During the blowing process, closely monitor the temperature of the molten bath. By adjusting the oxygen flow rate and blowing time, control the temperature of the molten bath at 1500 °C. At the same time, control the basicity of the slag CaO / SiO2 at 2.8, and adjust the slag composition by adding slag-making agents such as lime and dolomite. When the basicity of the slag deviates from the target range, timely adjust the addition amount of the slag-making agent. In addition, in the later stage of blowing, according to the carbon content and temperature of the molten steel, reasonably control the tapping temperature to keep it at 1670 °C.

[0167] During the converter tapping process, argon stirring is carried out throughout the process; slag blocking is carried out before and after tapping to control the slag falling amount and ensure the thickness of the ladle slag is 70 mm; when 1 / 3 of the steel is tapped, add 480 kg / ton of molten steel of lime and 180 kg / ton of molten steel of composite refining slag for slag washing; then through quenching treatment, semiconductor ultra-pure steel is obtained.

[0168] During the refining process, the operation of making white slag is carried out, the quaternary basicity of the slag is controlled at 3, the refining tapping temperature is controlled at 1580 °C, and the refining time is 50 min.

[0169] The quenching treatment is as follows:

[0170] S1 Pretreatment: Clean the surface of the steel code to remove oil stains, and preheat it to 680 °C to remove internal stress;

[0171] S2 Quenching preparation: Prepare a quenching agent with a certain concentration, and check the quenching equipment to ensure normal operation;

[0172] S3 Austenitization: Heat the pre-treated steel code to 1070 °C and hold for a certain period to completely transform the internal structure into austenite;

[0173] S4 Quenching execution: Quench the austenitized steel code rapidly in the quenching liquid, controlling the stirring speed and the temperature of the quenching liquid;

[0174] S5 Post-treatment: After quenching, clean and dry the steel code, and perform tempering treatment to eliminate the quenching stress;

[0175] S6 Quality inspection: Include hardness testing and metallographic analysis to confirm that the quenched steel code meets the standards;

[0176] The quenching liquid is obtained by mixing the quenching agent with water, where the volume ratio concentration range of the quenching agent is 12% to ensure rapid and uniform cooling of the steel code during quenching.

[0177] The preparation method of the described quenching agent is: by mass percentage:

[0178] Borane-based polyether: 10%; Sodium chloride: 1%; Sodium dodecyl sulfate 0.3%; Sodium benzoate: 0.6%; Sodium molybdate: 0.22%; Defoaming agent: 0.07%; Deionized water: the balance;

[0179] The preparation method of the described borane-based polyether is:

[0180] Add 8 kg of methyl allyl alcohol polyether and 160 kg of dichloroethane to the reaction kettle 1, stir for 70 minutes at a temperature of 75 °C; then add 0.4 kg of sodium mercaptododecaborane disodium salt, 0.1 kg of 3-mercaptoquinoline, and 0.9 kg of triethylamine, and continue to stir for 80 minutes at the same temperature; afterwards, remove the dichloroethane by distillation to obtain the borane-based polyether.

[0181] The described defoaming agent is BYK-035.

[0182] The described methyl allyl alcohol polyether has a molecular weight of 1000.

[0183] Example 4

[0184] A method for efficient smelting of semiconductor ultra-pure steel with precisely controlled components, the weight percentages of its chemical components are: C: 0.007%;

[0185] Si: 0.14%;

[0186] Mn: 0.045%;

[0187] P: ≤0.008%;

[0188] S: ≤0.0008%;

[0189] Ni: 14.9%;

[0190] Cr: 16.9%;

[0191] Mo: 2.4%;

[0192] Cu: 0.18%;

[0193] Al: 0.007%;

[0194] Nb: 0.011%;

[0195] Ti: 0.011%;

[0196] Se: 0.011%;

[0197] Ca: 0.011%;

[0198] O: 12 ppm;

[0199] H: 1.5 ppm;

[0200] N: 70 ppm; the balance is iron:

[0201] Its operation steps include: hot metal desulfurization, converter blowing, tapping from the converter, refining, and protected casting.

[0202] The hot metal desulfurization mentioned above adopts top injection desulfurization on the mixer car roof; the addition amount of the desulfurizer is 6 kg / ton of molten steel, and the nitrogen flow rate is 550 m3 / h; the desulfurizer composition is 40% calcium carbide, 30% calcium oxide, and the rest is calcium carbonate.

[0203] The process of converter blowing is as follows:

[0204] Charging preparation: Check the lining condition of the converter to ensure that the lining has no serious erosion or damage. Pour the desulfurized hot metal into the converter.

[0205] Bottom blowing gas control: Adopt the switching mode of nitrogen and argon for bottom blowing, switch every 10 min, and the blowing flow rate is 550 Nm 3 / h. When switching the gas, ensure the normal operation of the gas switching device to avoid gas leakage or untimely switching. Through the stirring action of the bottom blowing gas, promote the uniformity of the composition and temperature of the molten steel, and at the same time facilitate the removal of impurities.

[0206] Temperature and alkalinity control: During the blowing process, closely monitor the temperature of the molten bath. By adjusting the oxygen flow rate and blowing time, control the temperature of the molten bath at 1550 °C. At the same time, control the slag alkalinity CaO / SiO2 at 3.0. Adjust the slag composition by adding slag formers such as lime and dolomite. When the slag alkalinity deviates from the target range, promptly adjust the addition amount of the slag former. In addition, at the later stage of blowing, reasonably control the tapping temperature according to the carbon content and temperature of the molten steel, and keep it at 1680 °C.

[0207] During the tapping process of the converter, argon stirring is carried out throughout the process; slag blocking is carried out before and after tapping to control the amount of slag flowing down and ensure that the thickness of the ladle slag is 80 mm; when 1 / 3 of the steel is tapped, add 500 kg of lime per ton of molten steel and 200 kg of composite refining slag per ton of molten steel for slag washing; then, through quenching treatment, semiconductor ultra-pure steel is obtained.

[0208] During the refining process, the operation of making white slag is carried out. The four-component alkalinity of the slag is controlled at 3, the refining tapping temperature is controlled at 1600 °C, and the refining time is 60 min.

[0209] The quenching treatment is as follows:

[0210] S1 Pretreatment: Clean the surface of the steel ingot, remove the oil stain, and preheat it to 700 °C to remove the internal stress;

[0211] S2 Quenching preparation: Prepare a quenching agent with a certain concentration and check the quenching equipment to ensure normal operation;

[0212] S3 Austenitization: Heat the pretreated steel ingot to 1080 °C and keep it for a certain time to completely transform the internal structure into austenite;

[0213] S4 Quenching execution: Quickly quench the austenitized steel ingot in the quenching liquid, and control the stirring speed and the temperature of the quenching liquid;

[0214] S5 Post-treatment: After quenching, clean and dry the steel ingot, and carry out tempering treatment to eliminate the quenching stress;

[0215] S6 Quality inspection: Include hardness test and metallographic analysis to confirm that the quenched steel ingot meets the standards;

[0216] The quenching liquid is obtained by mixing the quenching agent with water. The volume ratio concentration range of the quenching agent is 15% to ensure that the steel ingot can be cooled quickly and evenly during the quenching process.

[0217] The preparation method of the quenching agent is as follows: By mass percentage:

[0218] Boranyl polyether: 12%; Sodium chloride: 3%; Sodium dodecyl sulfate: 0.5%; Sodium benzoate: 0.8%; Sodium molybdate: 0.3%; Defoamer: 0.1%; Deionized water: the balance;

[0219] The preparation method of the boranyl polyether is as follows:

[0220] Add 10 kg of allyl alcohol polyether and 200 kg of dichloroethane into the reaction kettle 1, and stir for 100 minutes at a temperature of 80 °C; then add 0.5 kg of sodium mercaptododecaborane disodium salt, 0.2 kg of 3-mercaptoquinoline, and 2 kg of triethylamine, and continue to stir for 100 minutes at the same temperature; after that, remove dichloroethane by distillation to obtain boranyl polyether.

[0221] The defoamer used is BYK-044.

[0222] The allyl alcohol polyether has a molecular weight of 1000.

[0223] Comparative Example 1

[0224] Do not add quenching liquid, and the others are the same as in Example 1.

[0225] Comparative Example 2

[0226] Do not add sodium mercaptododecaborane disodium salt, and the others are the same as in Example 1.

[0227] Comparative Example 3

[0228] Do not add 3-mercaptoquinoline, and the others are the same as in Example 1.

[0229] Table 1 Detection data table of Examples 1-4 and Comparative Examples 1-3

[0230]

[0231] Through the data analysis of the above examples and comparative examples, the ultra-pure steel prepared by the present invention has excellent mechanical properties.

[0232] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the above-disclosed technical content to obtain equivalent embodiments with equivalent changes, but as long as the technical content of the present invention is not departed from, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A high-efficiency smelting method for semiconductor ultra-pure steel with precisely controlled components, and the weight percentages of its chemical components are as follows: C：0.004-0.007％； Si: 0.10 - 0.14%; Mn: 0.035 - 0.045%; P：≤0.008％； S：≤0.0008％； Ni: 14.6 - 14.9%; Cr：16.6-16.9％； Mo: 2.3 - 2.4%; Cu: 0.12 - 0.18%; Al：0.005-0.007％； Nb: 0.009 - 0.011%; Ti: 0.009 - 0.011%; Se: 0.009 - 0.011%; Ca: 0.009 - 0.011%; O: 8 - 12 ppm; H: 0.5 - 1.5 ppm; N: 60 - 70 ppm; the balance is iron: Its operating steps include: Hot metal desulfurization, converter blowing, converter tapping, refining, and protective casting; The converter tapping needs to be quenched to obtain semiconductor ultra-pure steel; When performing the quenching treatment, a quenching agent is required, and the quenching agent is prepared by reacting borane polyether, sodium chloride, sodium dodecyl sulfate, sodium benzoate, sodium molybdate, defoaming agent, and water.

2. The high-efficiency smelting method of semiconductor ultra-pure steel with precisely regulated components according to claim 1, characterized in that: The hot metal desulfurization is carried out by top spraying desulfurization on the torpedo car; the addition amount of the desulfurizer is 4-6 kg per ton of molten steel, and the nitrogen flow rate is 450-550 m 3 / h; the desulfurizer composition is 30-40% calcium carbide, 25-30% calcium oxide, and the rest is calcium carbonate.

3. The high-efficiency smelting method of semiconductor ultra-pure steel with precisely controlled components according to claim 1, characterized in that: The converter blowing is carried out by bottom blowing in a nitrogen and argon switching mode, with a switching interval of 10 minutes and a blowing flow rate of 450 - 550 Nm 3 / h.

4. The high-efficiency smelting method of semiconductor ultra-pure steel with precisely regulated components according to claim 1, characterized in that: The process of converter blowing is as follows: Charging preparation: Check the lining condition of the converter to ensure that the lining has no serious erosion or damage, and pour the desulfurized hot metal into the converter; Bottom-blowing gas control: Nitrogen and argon are used in a switching mode for bottom-blowing, with a switching interval of 10 minutes. The blowing flow rate is 450 - 550 Nm 3 / h. When switching gases, ensure the normal operation of the gas switching device to avoid gas leakage or untimely switching. Through the agitation of the bottom-blowing gas, promote the homogenization of the molten steel's composition and temperature, and at the same time facilitate the removal of impurities; Temperature and basicity control: During the blowing process, closely monitor the molten bath temperature. By adjusting the oxygen flow rate and blowing time, control the molten bath temperature at 1450 - 1550 °C. At the same time, control the slag basicity CaO / SiO2 at 2.5 - 3.

0. Adjust the slag composition by adding slag-making agents such as lime and dolomite. When the slag basicity deviates from the target range, promptly adjust the addition amount of the slag-making agent. In addition, at the later stage of blowing, reasonably control the stopping blowing temperature according to the carbon content and temperature of the molten steel to keep it at 1650 - 1680 °C.

5. A method for efficiently smelting semiconductor ultra-pure steel with precisely controlled components according to claim 1, characterized in that: During the whole process of converter tapping, argon stirring is carried out; slag blocking is performed before and after tapping to control the slag falling amount and ensure that the ladle slag thickness is 50 - 80 mm; when 1 / 3 of the steel is tapped, add 400 - 500 kg / ton of molten steel of lime and 100 - 200 kg / ton of molten steel of composite refining slag for slag washing; then, after quenching treatment, semiconductor ultra-pure steel is obtained.

6. The high-efficiency smelting method of semiconductor ultra-pure steel with precisely controlled components according to claim 1, characterized in that: During the refining process, white slag making operation is carried out, the quaternary basicity of the slag is controlled at 2 - 3, the refining tapping temperature is controlled at 1600 - 1650 °C, and the refining time is 30 - 60 min.

7. A method for efficiently smelting semiconductor ultra-pure steel with precisely controlled components according to claim 5, characterized in that: The quenching treatment is as follows: S1 Pretreatment: Clean the surface of the steel code, remove oil stains, and preheat it to 600 - 700 °C to remove internal stress; S2 Quenching preparation: Configure a quenching agent with a certain concentration and check the quenching equipment to ensure normal operation; S3 Austenitization: Heat the pretreated steel code to 1000 - 1080 °C and keep it for a certain time to completely transform the internal structure into austenite; S4 Quenching execution: Quench the austenitized steel code rapidly in the quenching liquid, and control the stirring speed and quenching liquid temperature; S5 Post-treatment: After quenching, clean and dry the steel code, and perform tempering treatment to eliminate quenching stress; S6 Quality inspection: Include hardness testing and metallographic analysis to confirm that the quenched steel code meets the standards; The quenching liquid is obtained by mixing the quenching agent with water, where the volume ratio concentration range of the quenching agent is 5 - 15% to ensure rapid and uniform cooling of the steel code during quenching.

8. An efficient smelting method for semiconductor ultra-pure steel with precisely controlled components according to claim 7, characterized in that: The preparation method of the quenching agent is as follows by mass percentage: 8 - 12% of boralkyl polyether; 0.5 - 3% of sodium chloride; 0.1 - 0.5% of sodium dodecyl sulfate; 0.3 - 0.8% of sodium benzoate, 0.1 - 0.3% of sodium molybdate; 0.05 - 0.1% of defoamer; the balance is deionized water; mix evenly to obtain the quenching agent.

9. The highly efficient smelting method of semiconductor ultra-pure steel with precisely controlled components according to claim 8, characterized in that: The preparation method of the boralkyl polyether is as follows: Add 5 - 10 parts by weight of methyl allyl alcohol polyether and 100 - 200 parts by weight of dichloroethane into the reaction kettle 1, stir for 50 - 100 minutes at a temperature of 70 - 80 °C; then add 0.2 - 0.5 parts of sodium mercaptododecaborane disodium salt, 0.03 - 0.2 parts by weight of 3 - mercaptoquinoline, 0.5 - 2 parts by weight of triethylamine, and continue to stir for 50 - 100 minutes at the same temperature; then remove dichloroethane by distillation to obtain boralkyl polyether.

10. A method for efficiently smelting semiconductor ultra-pure steel with precisely controlled components according to claim 8, characterized in that: The defoamer is at least one of BYK - 024, BYK - 025, BYK - 035, and BYK - 044.

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