Production method for improving performance of low-aluminum high-carbon bearing steel material

Abstract

The invention discloses a production method for improving the performance of a low-aluminum high-carbon bearing steel material, which comprises the following steps: (1) electric furnace steelmaking: selecting 50% of scrap steel and 50% of desulfurized molten iron for smelting, controlling the target value of phosphorus below 0.01%, and adding aluminum iron at one time in the electric furnace steelmaking process; (2) LF refining: controlling the slag alkalinity to be 4.0-8.0 before refining, adjusting the alloy content of molten steel to a target value in the refining process, and controlling the Nb content to be 0.015-0.050%; (3) RH vacuum degassing, wherein the vacuum pressure maintaining time is longer than or equal to 25 min; (4) casting: the process heat in the casting process is 15-25 DEG C, a light and heavy reduction device is adopted at the continuous casting solidification tail end, and the total reduction is 15-30 mm; (5) rolling; the method is suitable for producing the round steel for the bearing with the diameter phi being 16-90 mm, the number of production furnaces in the continuous casting process can be effectively increased, the performance of the low-aluminum high-carbon bearing steel can be effectively improved, and the continuous casting production efficiency is obviously improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of bearing steel, and particularly relates to a production method for improving the material properties of low-aluminum and high-carbon bearing steel. Background Art

[0002] With the rapid development of modern industry, higher challenges are posed to the material properties of industrial basic components. For bearings, the service environment is harsh and requires better raw material support to meet the requirements of bearing components such as high temperature resistance, wear resistance, low noise, and long life. Under high requirements, not only the surface quality, chemical composition, structure, and properties of the raw materials need to meet the technical requirements of GB / T18254, but also the fatigue life of the material is required to be very high. The quantity, size, and morphology of non-metallic inclusions in steel are one of the important factors affecting the fatigue performance of the material.

[0003] Steel mills adopt the method of low-aluminum deoxidation to better increase production. This method can significantly improve the number of casting furnaces during continuous casting. During the smelting process of bearing steel, aluminum is a very effective deoxidizer. At present, the aluminum content in the bearing steel produced by each steel mill in China is between 0.015% and 0.030%, and the final T.O content of the product can be controlled within 6 ppm, which can meet the requirements of special-grade bearing steel. During high-aluminum smelting, it is easy to accumulate flow at the nozzle during continuous casting, block the nozzle, and cause the continuous casting machine to stop pouring, affecting production efficiency.

[0004] To improve the problem of casting flow accumulation, low-aluminum or aluminum-free deoxidation can be adopted. Since aluminum can not only deoxidize in bearing steel but also greatly improve the material properties, especially refine the grain size of the material, using low-aluminum or aluminum-free deoxidation will lead to a reduction in material properties.

[0005] Chinese Patent CN 114427016A discloses a production method of aluminum-free bearing steel, which elaborates in detail that the number of continuous casting furnaces is greatly increased by reducing the aluminum content in bearing steel during the smelting process, and the quality of the continuous casting billet is qualified, but the performance of the final round steel product is not mentioned. Summary of the Invention

[0006] The purpose of the present invention is to provide a production method for improving the material properties of low-aluminum and high-carbon bearing steel, which is applicable to the production of round steel for bearings. This method can effectively increase the number of production furnaces during continuous casting and the performance of low-aluminum and high-carbon bearing steel, and significantly improve the production efficiency of continuous casting.

[0007] The technical solution adopted by the present invention is as follows:

[0008] A production method for improving the material properties of low-aluminum and high-carbon bearing steel, the production method comprising the following steps:

[0009] (1) Electric furnace steelmaking: 50% scrap steel and 50% desulfurized hot metal are used for smelting. After primary smelting in an electric furnace, the steel is decarbonized and dephosphorized. The phosphorus target value is controlled below 0.01%. During the electric furnace steelmaking process, aluminum iron is added once to control the aluminum content in the molten steel to be within 0.025%. Aluminum deoxidation is not allowed after the steel is tapped from the electric furnace.

[0010] (2) LF refining: In the early stage of refining, the slag basicity is controlled between 4.0 and 8.0. During the refining process, the alloy content of the molten steel is adjusted to the target value, wherein the Nb content is controlled between 0.015% and 0.050%;

[0011] (3) RH vacuum degassing: After heating to a predetermined temperature, the furnace is hoisted to the RH furnace for vacuum smelting, and the vacuum pressure holding time is ≥ 25 minutes;

[0012] (4) Casting: During the casting process, the process temperature is 15-25°C, and a light and heavy pressure reduction device is used at the end of continuous casting solidification, with a total pressure reduction of 15-30 mm;

[0013] (5) Rolling.

[0014] In step (1), a slide plate is used to block slag when the electric furnace is finished tapping steel.

[0015] In step (2), the LF refining process is carried out by silicon manganese pre-deoxidation, diffusion deoxidation and vacuum deoxidation to ensure that the total oxygen content is within the requirement of 9 ppm for high-quality bearing steel.

[0016] In step (3), the oxygen is determined after vacuum breaking, and the oxygen content is ≤7ppm. After soft blowing, the large package is hoisted to the continuous casting platform for casting.

[0017] In step (4), 7-stage tundish induction heating is used during the casting process.

[0018] In step (5), the heating furnace temperature is 1230-1250°C, heating is performed for 4-6 hours, and then the steel sheet is rolled into Round steel.

[0019] The low aluminum high carbon bearing steel includes the following chemical components in weight percentage: C: 0.98-1.03%, Si: 0.20-0.30%, Mn: 0.30-0.40%, P≤0.020%, S: ≤0.015%, Cr: 1.45-1.55%, Al: 0.010%-0.015%, Nb: 0.015%-0.050%, Mo≤0.10%, Ni≤0.30%, Cu≤0.20%, and the rest is Fe and unavoidable impurities.

[0020] In the low-aluminum high-carbon bearing steel, the distribution area of ​​the network carbide satisfies the 2.0 level within the 1 / 3 radius of the center; niobium-containing carbides are segregated and precipitated at the grain boundaries, causing the carbide network to become discontinuously distributed.

[0021] The metallographic structure of the low-aluminum high-carbon bearing steel is pearlite+cementite, and the grain size is grade 8.5.

[0022] In the production method for improving the performance of low-aluminum high-carbon bearing steel provided by the present invention, in order to ensure the purity of molten steel and the content of harmful elements phosphorus and sulfur, 50% scrap steel and 50% desulfurized iron water are selected as the raw materials for steelmaking for smelting, and decarburization and dephosphorization are carried out in the electric furnace. The phosphorus target value is controlled below 0.01%. In order to prevent the problem of continuous casting nozzle accumulation caused by adding aluminum wire deoxidation during the refining process, aluminum iron is added once during the electric furnace steelmaking process, and aluminum deoxidation is not allowed after the electric furnace is tapped. A slide plate is used to block slag at the end of the electric furnace tapping to prevent the slag in the electric furnace molten steel from entering the large bag.

[0023] During the smelting process of bearing steel, the oxygen content is controlled at a low level. Before refining, the slag basicity needs to be controlled between 4.0-8.0. Too high or too low basicity is not conducive to the control of the oxygen content of molten steel. The aluminum content in molten steel is controlled within 0.025%. During the refining process, the alloy content of the molten steel is adjusted to the target value. After heating and reaching the predetermined temperature, it is hoisted to the RH furnace for vacuum smelting. Since bearing steel has high requirements for the control of harmful gas content of hydrogen, nitrogen and oxygen, the harmful gas cannot be removed completely if the vacuum insulation time is too low, and the smelting cost is low and the cycle is increased if the time is too high, so the high vacuum pressure holding time is ≥25min.

[0024] In order to ensure the grain size and mechanical properties of low aluminum deoxidized bearing steel round steel, a small amount of niobium is added during the LF refining process, and the Nb content is controlled between 0.015% and 0.050%. Silicon manganese pre-deoxidation, diffusion deoxidation and vacuum deoxidation are used during the refining process to ensure that the total oxygen content is within the 9ppm required by high-quality bearing steel.

[0025] After vacuum breaking, the ladle is lifted to the continuous casting platform for casting after fixed oxygen soft blowing. In order to ensure the uniform composition and continuous casting of the billet during casting, the 7-stage tundish induction heating technology is used during casting to ensure that the process temperature is between 15 and 25°C. If the overheating is too high, the billet will be severely segregated, and too low is not conducive to molten steel casting. In order to improve the dendrite segregation of the billet, a light and heavy pressure device is used at the end of continuous casting solidification. The total pressure reduction is between 15 and 30 mm. A large pressure reduction is not conducive to the continuous casting billet shape control, and a small pressure reduction is not conducive to improving the dendrite segregation. The target value is 20 mm.

[0026] After slow cooling, the continuous casting billet is transported to the bar production line for rolling. The heating furnace temperature is 1230-1250℃, and the heating time is 4-6 hours. Then, the initial rolling, intermediate rolling and finishing rolling are carried out. Round steel.

[0027] The production method provided by the present invention can effectively increase the number of continuous casting heats of bearing steel, with the number of continuous casting heats ≥ 6 heats, by controlling the key processes during steelmaking, especially the control of the effective deoxidation Al content and the selection of the deoxidation method, and ensuring the T.O content in the bearing steel. Secondly, a trace amount of niobium component is added in the LF furnace to make up for the performance differences of low-aluminum bearing steel, especially the role of aluminum in refining grains. Adding a trace amount of niobium to the bearing steel increases the grain boundary area. Therefore, the distribution area of the carbide network increases, and the precipitation amount at the grain boundary will decrease (the precipitation of carbides at the grain boundary will damage the structural force between grains. The more carbides precipitate and form a network, the more seriously the bonding force between the grains of the material is damaged). The niobium-containing carbides segregate and precipitate at the grain boundary, reducing the interfacial energy and consuming the surrounding carbon, making the carbide network become discontinuously distributed. Description of the Drawings

[0028] Figure 1 It is the grain size diagram of the bearing steel in Example 1, with a grain size of 8.5 grades;

[0029] Figure 2 It is the grain size diagram of the bearing steel in Comparative Example 1, with a grain size of 7.5 grades;

[0030] Figure 3 It is the grain size diagram of the bearing steel in Comparative Example 2, with a grain size of 8.5 grades;

[0031] Figure 4 It is the grain size diagram of the bearing steel in Comparative Example 3, with a grain size of 7.0 grades;

[0032] Figure 5 It is the carbide network diagram of the bearing steel in Example 1, with a carbide network grade of 2.0 grades;

[0033] Figure 6 It is the carbide network diagram of the bearing steel in Comparative Example 1, with a carbide network grade of 3.0 grades;

[0034] Figure 7 It is the carbide network diagram of the bearing steel in Comparative Example 2, with a carbide network grade of 2.0 grades;

[0035] Figure 8 It is the carbide network diagram of the bearing steel in Comparative Example 3, with a carbide network grade of 3.5 grades. Detailed Embodiments

[0036] The present invention provides a production method for improving the material performance of low-aluminum high-carbon bearing steel, and the production method includes the following steps:

[0037] (1) Electric furnace steelmaking: 50% scrap steel + 50% desulfurized iron water is used for smelting. After primary smelting in the electric furnace, decarburization and dephosphorization are carried out. The phosphorus target value is controlled below 0.01%. During the electric furnace steelmaking process, aluminum iron is added once to control the aluminum content in the molten steel to be within 0.025%. Aluminum deoxidation is not allowed after the electric furnace is tapped. A slide plate is used to block the slag after the electric furnace is tapped.

[0038] (2) LF refining: The slag basicity is controlled between 4.0 and 8.0 in the early stage of refining. During the refining process, the alloy content of the molten steel is adjusted to the target value, and the Nb content is controlled at 0.015% to 0.050%. During the LF refining process, silicon-manganese pre-deoxidation, diffusion deoxidation and vacuum deoxidation are used to ensure that the total oxygen content is within the requirement of 9ppm for high-quality bearing steel.

[0039] (3) RH vacuum degassing: After heating to 1497-1512℃, it is hoisted to the RH furnace for vacuum smelting, and the vacuum pressure holding time is ≥25min; after vacuum breaking, the oxygen content is determined, and the oxygen content is ≤7ppm. After soft blowing, the large package is hoisted to the continuous casting platform for casting.

[0040] (4) Casting: During the casting process, a 7-stage tundish is used for induction heating, the process temperature during the casting process is 15-25°C, and a light and heavy pressure reduction device is used at the end of continuous casting solidification, with a total pressure reduction of 15-30 mm;

[0041] (5) Rolling: The heating furnace temperature is 1230-1250℃, heating for 4-6 hours, and then rolling through initial rolling, intermediate rolling and finishing rolling. Round steel.

[0042] The low aluminum high carbon bearing steel includes the following chemical components in weight percentage: C: 0.98-1.03%, Si: 0.20-0.30%, Mn: 0.30-0.40%, P≤0.020%, S: ≤0.015%, Cr: 1.45-1.55%, Al: 0.010%-0.015%, Nb: 0.015%-0.050%, Mo≤0.10%, Ni≤0.30%, Cu≤0.20%, and the rest is Fe and unavoidable impurities.

[0043] The present invention is described in detail below with reference to the embodiments.

[0044] Example 1

[0045] A production method for improving the performance of low-aluminum high-carbon bearing steel materials, comprising the following steps:

[0046] (1) Electric furnace steelmaking: 50% scrap steel and 50% desulfurized iron water are used for smelting. After primary smelting in the electric furnace, decarburization and dephosphorization are carried out. The phosphorus target value is controlled below 0.01%. During the electric furnace steelmaking process, aluminum iron is added once to control the aluminum content in the molten steel to 0.011%. Aluminum deoxidation is not allowed after the electric furnace is tapped. A slide plate is used to block the slag after the electric furnace is tapped.

[0047] (2) LF refining: The slag basicity is controlled at 7.1 before refining. During the refining process, the alloy content of the molten steel is adjusted to the target value, wherein the Nb content is controlled at 0.025%. During the LF refining process, silicon-manganese pre-deoxidation, diffusion deoxidation and vacuum deoxidation are used to ensure that the total oxygen content is 6.8 ppm.

[0048] (3) RH vacuum degassing: After heating to 1500℃, the steel is hoisted to the RH furnace for vacuum smelting, and the vacuum pressure holding time is 25 minutes. After vacuum breaking, the oxygen content is determined to be 6.7ppm. After soft blowing, the large package is hoisted to the continuous casting platform for casting.

[0049] (4) Casting: During the casting process, a 7-stage tundish was used for induction heating. The process temperature during the casting process was 24°C. A light and heavy pressure reduction device was used at the end of the continuous casting solidification, with a total pressure reduction of 24 mm. This method can achieve stable casting of 8 furnaces of molten steel.

[0050] (5) Rolling: The heating furnace temperature is 1240℃, heated for 6 hours, and then rolled through initial rolling, intermediate rolling and finishing rolling. Round steel.

[0051] The chemical composition and weight percentage of the low-aluminum high-carbon bearing steel are: C: 0.97%, Si: 0.26%, Mn: 0.34%, P: 0.010%, S: 0.002%, Cr: 1.45%, Al: 0.011%, Nb: 0.025%, Mo: 0.06%, Ni: 0.028%, Cu: 0.03%, and the rest are Fe and unavoidable impurities.

[0052] Comparative Example 1

[0053] A method for producing bearing steel comprises the following steps:

[0054] (1) Electric furnace steelmaking: 50% scrap steel and 50% desulfurized iron water are used for smelting. After primary smelting in the electric furnace, decarburization and dephosphorization are carried out. The phosphorus target value is controlled below 0.01%. During the electric furnace steelmaking process, aluminum iron is added once to control the aluminum content in the molten steel to 0.012%. Aluminum deoxidation is not allowed after the electric furnace is tapped. A slide plate is used to block the slag after the electric furnace is tapped.

[0055] (2) LF refining: The slag basicity is controlled at 6.2 before refining. During the refining process, the alloy content of the molten steel is adjusted to the target value, wherein the Nb content is controlled to be less than 0.001%. During the LF refining process, silicon-manganese pre-deoxidation, diffusion deoxidation and vacuum deoxidation are used to ensure that the total oxygen content is 7.4 ppm.

[0056] (3) RH vacuum degassing: After heating to 1500℃, the steel is hoisted to the RH furnace for vacuum smelting, and the vacuum pressure holding time is 25 minutes. After vacuum breaking, the oxygen content is determined to be 6.6ppm. After soft blowing, the large package is hoisted to the continuous casting platform for casting.

[0057] (4) Casting: During the casting process, a 7-stage tundish was used for induction heating. The process temperature during the casting process was 23°C. A light and heavy pressure reduction device was used at the end of the continuous casting solidification, with a total pressure reduction of 24 mm. This method can achieve stable casting of 5 furnaces of molten steel.

[0058] (5) Rolling: The heating furnace temperature is 1240℃, heated for 6 hours, and then rolled through initial rolling, intermediate rolling and finishing rolling. Round steel.

[0059] The chemical composition and weight percentage of the low-aluminum high-carbon bearing steel are: C: 0.98%, Si: 0.26%, Mn: 0.34%, P: 0.012%, S: 0.003%, Cr: 1.46%, Al: 0.0012%, Nb: 0.0004%, Mo: 0.06%, Ni: 0.028%, Cu: 0.03%, and the rest are Fe and unavoidable impurities.

[0060] Comparative Example 2

[0061] A method for producing bearing steel comprises the following steps:

[0062] (1) Electric furnace steelmaking: 50% scrap steel and 50% desulfurized iron water are used for smelting. After primary smelting in the electric furnace, decarburization and dephosphorization are carried out. The phosphorus target value is controlled below 0.01%. During the electric furnace steelmaking process, aluminum iron is added once to control the aluminum content in the molten steel to 0.019%. Aluminum deoxidation is not allowed after the electric furnace is tapped. A slide plate is used to block the slag after the electric furnace is tapped.

[0063] (2) LF refining: The slag basicity is controlled at 6.4 before refining. During the refining process, the alloy content of the molten steel is adjusted to the target value, wherein the Nb content is controlled to be less than 0.001%. During the LF refining process, silicon-manganese pre-deoxidation, diffusion deoxidation and vacuum deoxidation are used to ensure that the total oxygen content is 5.8 ppm.

[0064] (3) RH vacuum degassing: After heating to 1500 °C, it is lifted by the overhead crane to the RH furnace for vacuum smelting. The vacuum holding time is 23 minutes. After the vacuum is broken, the oxygen is determined, and the oxygen content is 6.9 ppm. After soft blowing, the ladle is lifted to the continuous casting platform for casting.

[0065] (4) Casting: During the casting process, 7-stage tundish induction heating is adopted. The process heat during casting is 21 °C. The light and heavy soft reduction device is used at the end of continuous casting solidification, and the total reduction amount is 22 mm. This method can achieve stable casting of 4 heats of molten steel.

[0066] (5) Rolling: The heating furnace temperature is 1240 °C, and it is heated for 6 hours. Then it is rolled into round steel through primary rolling, intermediate rolling, and finish rolling. Round steel.

[0067] The chemical composition and weight percentage of the low-aluminum high-carbon bearing steel are as follows: C: 0.98%, Si: 0.25%, Mn: 0.33%, P: 0.011%, S: 0.003%, Cr: 1.47%, Al: 0.019%, Nb: 0.0008%, Mo: 0.06%, Ni: 0.028%, Cu: 0.03%, and the rest is Fe and unavoidable impurities.

[0068] Comparative Example 3

[0069] A production method of bearing steel includes the following steps:

[0070] (1) Electric furnace steelmaking: 50% scrap steel and 50% desulfurized hot metal are selected for smelting. After primary melting in the electric furnace to decarbonize and dephosphorize, the target value of phosphorus is controlled below 0.01%. During the electric furnace steelmaking process, ferrotitanium is added at one time to control the aluminum content in the molten steel to 0.003%. After tapping from the electric furnace, aluminum deoxidation is not allowed. After the tapping of the electric furnace is completed, a slide gate is used to block the slag.

[0071] (2) LF refining: The slag basicity before refining is controlled at 7.0. During the refining process, the alloy content of the molten steel is adjusted to the target value, and the Nb content is controlled at 0.025%. During the LF refining process, silicon manganese pre-deoxidation, diffusion deoxidation, and vacuum deoxidation are adopted to ensure that the total oxygen content is 9.4 ppm.

[0072] (3) RH vacuum degassing: After heating to 1500 °C, it is lifted by the overhead crane to the RH furnace for vacuum smelting. The vacuum holding time is 27 minutes. After the vacuum is broken, the oxygen is determined, and the oxygen content is 7.4 ppm. After soft blowing, the ladle is lifted to the continuous casting platform for casting.

[0073] (4) Casting: During the casting process, 7-stage tundish induction heating is adopted. The process heat during casting is 25 °C. The light and heavy soft reduction device is used at the end of continuous casting solidification, and the total reduction amount is 21 mm. This method can achieve stable casting of 6 heats of molten steel.

[0074] (5) Rolling: The temperature of the heating furnace is 1240 °C, and it is heated for 6 hours. Then it is rolled into round steel through rough rolling, intermediate rolling, and finish rolling. Round steel.

[0075] The chemical composition and weight percentage of the low-aluminum high-carbon bearing steel are as follows: C: 0.99%, Si: 0.27%, Mn: 0.35%, P: 0.012%, S: 0.003%, Cr: 1.46%, Al: 0.003%, Nb: 0.0005%, Mo: 0.06%, Ni: 0.028%, Cu: 0.03%, and the rest is Fe and inevitable impurities.

[0076] The round steel specimens prepared in the above examples and comparative examples are subjected to microstructure and property tests:

[0077] Grain size test: First, take the hot-rolled round steel, saw it into specimens of 20 mm × 20 mm × 20 mm, heat it at 860 °C for 1 hour, quench it in water to room temperature, etch it with an etching solution, and observe it under a microscope.

[0078] Carbide network test: First, take the hot-rolled specimen, quench and temper it according to the regulations in GB / T18254-2016, etch it with a 4% nitric acid alcohol solution, and observe the precipitation of the carbide network in the material under a microscope.

[0079] The grain size test results of Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3 are as Figure 1 , 2 , 3, and 4 show. It can be seen from the figure that the grain size of the low-aluminum deoxidized bearing steel in Comparative Example 1 is 7.5 grades, the grain sizes of the low-aluminum deoxidized plus trace niobium material in Comparative Example 2 and the high-aluminum deoxidized material in Example 1 can be kept consistent at 8.5 grades, while the grain size of the non-aluminum deoxidized material in Comparative Example 3 is only 7.0 grades.

[0080] The carbide network diagrams of Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3 are as Figure 5 , 6 , 7, and 8 show. It can be seen from the figure that the carbide network grade of the low-aluminum deoxidized bearing steel in Comparative Example 1 is 3.0 grades, the carbide network grades of the low-aluminum deoxidized plus trace niobium material in Comparative Example 2 and the high-aluminum deoxidized material in Example 1 are 2.0 grades, while the carbide network grade of the non-aluminum deoxidized material in Comparative Example 3 is 3.5 grades.

[0081] The performance test results of the round steel specimens prepared in the above examples and comparative examples are shown in Table 1.

[0082] Table 1

[0083] Grain size Network of carbides Oxygen content Number of continuous casting furnaces Example 1 8.5 2.0 6.7 8 Comparative Example 1 7.5 3.0 6.6 5 Comparative Example 2 8.5 2.0 6.9 4 Comparative Example 3 7.0 3.5 7.4 6

[0084] The above detailed description of a production method for improving the material properties of low-aluminum and high-carbon bearing steel with reference to the embodiments is illustrative rather than restrictive. Several embodiments can be enumerated within the defined scope. Therefore, changes and modifications without departing from the general concept of the present invention shall fall within the protection scope of the present invention.

Claims

1. A production method for improving the material properties of low-aluminum and high-carbon bearing steel, characterized in that, The production method comprises the following steps: (1) Electric furnace steelmaking: 50% scrap steel and 50% desulfurized hot metal are used for smelting. After primary smelting in an electric furnace, the steel is decarbonized and dephosphorized. The phosphorus target value is controlled below 0.01%. During the electric furnace steelmaking process, aluminum iron is added once to control the aluminum content in the molten steel to be within 0.025%. Aluminum deoxidation is not allowed after the steel is tapped from the electric furnace. (2) LF refining: In the early stage of refining, the slag basicity is controlled between 4.0 and 8.

0. During the refining process, the alloy content of the molten steel is adjusted to the target value, wherein the Nb content is controlled between 0.015% and 0.050%; (3) RH vacuum degassing: After heating to 1497-1512℃, it is hoisted to the RH furnace for vacuum smelting, and the vacuum pressure holding time is ≥25min; (4) Casting: During the casting process, the process temperature is 15-25°C, and a light and heavy pressure reduction device is used at the end of continuous casting solidification, with a total pressure reduction of 15-30 mm; (5) Rolling.

2. The production method according to claim 1, characterized in that, In step (1), a slide plate is used to block slag when the electric furnace is finished tapping steel.

3. The production method according to claim 1, characterized in that, In step (2), the LF refining process is carried out by silicon manganese pre-deoxidation, diffusion deoxidation and vacuum deoxidation to ensure that the total oxygen content is within the requirement of 9 ppm for high-quality bearing steel.

4. The production method according to claim 1, characterized in that, In step (3), after vacuum breaking, oxygen is determined, and after soft blowing, the large bag is hoisted to the continuous casting platform for casting.

5. The production method according to claim 1, characterized in that, In step (4), 7-stage tundish induction heating is used during the casting process.

6. The production method according to claim 1, wherein In step (5), the heating furnace temperature is 1230-1250° C., heating is performed for 4-6 hours, and then the steel is rolled into φ16mm-φ90mm round steel through primary rolling, intermediate rolling and finish rolling.

7. The production method according to claim 1, characterized in that, The low aluminum high carbon bearing steel includes the following chemical components in weight percentage: C: 0.98-1.03%, Si: 0.20-0.30%, Mn: 0.30-0.40%, P≤0.020%, S: ≤0.015%, Cr: 1.45-1.55%, Al: 0.010%-0.015%, Nb: 0.015%-0.050%, Mo≤0.10%, Ni≤0.30%, Cu≤0.20%, and the rest is Fe and unavoidable impurities.

8. The production method according to claim 1, characterized in that, In the low-aluminum high-carbon bearing steel, the distribution area of ​​the network carbide satisfies the 2.0 level within the 1 / 3 radius of the center; niobium-containing carbides are segregated and precipitated at the grain boundaries, causing the carbide network to become discontinuously distributed.

9. The production method according to claim 1, characterized in that, The metallographic structure of the low-aluminum high-carbon bearing steel is pearlite+cementite, and the grain size is grade 8.5.

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