Machining process for hot rolling and cutting of bearing ring sleeve
By adding lanthanum-boron composite powder and vanadium-doped titanium dioxide to high-carbon chromium bearing steel, the problem of decreased hardenability caused by excessive rare earth cerium content was solved, and the high tensile strength and hardenability of high-carbon chromium bearing steel were synergistically improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HENAN SHENZHOU COLD ROLLING TECHNOLOGY CO LTD
- Filing Date
- 2026-03-09
- Publication Date
- 2026-05-08
AI Technical Summary
In high-carbon chromium bearing steel, when the rare earth cerium content increases to an excessive level, segregation occurs at the grain boundaries, affecting the diffusion of carbon atoms, leading to a decrease in hardenability, while the tensile strength improvement is limited.
By adding lanthanum-boron composite powder and vanadium-doped titanium dioxide during the preparation of high-carbon chromium bearing steel, the lanthanum-boron composite powder is used to suppress austenite grain boundary nucleation, and lanthanum generates spherical inclusions to improve anisotropy. The hardenability is improved by regulating the precipitation behavior, while the tensile strength is increased by increasing the rare earth cerium content.
This approach achieves a significant improvement in hardenability while simultaneously increasing tensile strength, thus synergistically enhancing the overall performance of high-carbon chromium bearing steel.
Smart Images
Figure CN121992285A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of alloy product technology, and in particular relates to a hot-rolled cutting process for bearing rings. Background Technology
[0002] Bearings, as the most basic and crucial components, are often referred to as the "joints" of high-end equipment. They are widely used in both major equipment (such as machine tools and automobiles) and emerging industries (such as wind power generation and high-speed trains). Bearing rings are annular parts of radial rolling bearings with one or more raceways; high-carbon chromium bearing steel is generally used in the production of bearing rings.
[0003] The addition of rare earth elements refines the steel microstructure, transforming large, irregular inclusions into smaller, more uniformly shaped rare earth inclusions, thus significantly reducing the likelihood of crack initiation and improving tensile strength. Therefore, in existing technologies, rare earth cerium is added during the preparation of high-carbon chromium bearing steel to improve the mechanical properties of bearing races. Within a certain range, the mechanical properties (tensile strength) of the high-carbon chromium bearing steel continuously improve with increasing rare earth addition / content.
[0004] However, at the same time, when the rare earth cerium content increases to an excessive level, some segregation will occur at the grain boundaries, which will have an adverse effect on the diffusion of carbon atoms and will also reduce the probability of cementite formation, resulting in a decrease in the hardenability of the steel (hardened layer depth / end quenching curve). Summary of the Invention
[0005] To address the aforementioned problems, this invention proposes a hot-rolled bearing ring cutting process that improves the mechanical properties (tensile strength) of the high-carbon chromium bearing steel by increasing the rare earth cerium content, while further enhancing its hardenability.
[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A hot-rolled bearing ring machining process includes the following steps: S1. By weight, add 95.3-95.8 parts of pure iron, 1.5-1.6 parts of chromium strips and 0.48-0.52 parts of carbon blocks to the vacuum induction furnace, start the vacuum pump, evacuate the vacuum induction furnace, and ensure that the pressure inside the vacuum induction furnace is ≤1Pa. Turn on the power and purge 50KPa argon gas into the vacuum induction furnace to begin the melting stage. S2. After melting and cleaning, add 0.45-0.5 parts of carbon blocks to the vacuum induction furnace again, evacuate the vacuum furnace, and perform carbon deoxidation. The vacuum degree is controlled at 15-18 Pa, the carbon deoxidation time is 30-35 min, and argon gas is introduced again at 10 kPa. S3. Add 0.04-0.045 parts of aluminum block, 0.5-0.6 parts of silicon block, and 0.8-0.85 parts of manganese block to the vacuum induction furnace of S2 in sequence. After 3-5 minutes, measure the temperature and adjust the power to reach 1500-1540℃. Add 0.015-0.016 parts of rare earth cerium, 0.011-0.013 parts of vanadium-doped titanium dioxide, and 0.03-0.035 parts of lanthanum-boron composite powder. Then, hold the temperature for 3-5 minutes and cast the material. After forging and heat treatment, the bearing steel round bar material is obtained. S4. The bearing steel round bar obtained in S3 is subjected to heating, piercing, rolling and hot cutting processes in sequence to obtain the hot-rolled and cut bearing ring.
[0007] Furthermore, the preparation method of the vanadium-doped titanium dioxide is as follows: A1. Mix 0.54 g cetyltrimethylammonium bromide, 52-55 mL anhydrous ethanol and 10-12 mL deionized water, then add 10-10.5 mL tetrabutyl titanate, 0.9-1 mL acetylacetone and 0.1 g ammonium metavanadate, stir at room temperature for 1 h to obtain solution one; A2. Mix 10.5-11.5 mL of anhydrous ethanol and 0.6-0.7 mL of deionized water, and adjust the pH to 3 ± 0.05 by adding concentrated nitric acid dropwise to obtain solution two; A3. Add the solution obtained in A2 to the solution obtained in A1 under magnetic stirring at a rate of 0.05-0.1 mL / s, and continue stirring for 4 hours to obtain a transparent and stable sol; after the sample gels, age and calcine to obtain the vanadium-doped titanium dioxide.
[0008] Furthermore, in A3, the specific aging process is as follows: first, age at room temperature for 9.5-11 hours, then raise the temperature to 65±2℃ and continue aging for another 9.5-11 hours.
[0009] Furthermore, in A3, the calcination temperature is 450±10℃, and the calcination time is 3-3.2h.
[0010] Furthermore, the lanthanum-boron composite powder comprises lanthanum powder and boron powder, and the mass ratio of the two is 2:1.
[0011] Furthermore, the preparation method of the lanthanum-boron composite powder is as follows: lanthanum powder and boron powder are mixed and dispersed in anhydrous ethanol dispersion medium by ball milling for 5-6 hours, and then vacuum dried to obtain the final product.
[0012] Furthermore, the specific washing operation is as follows: the drying temperature is 60±2℃, and the drying time is 9-12h.
[0013] Furthermore, in S3, the specific forging operation is as follows: the steel ingot obtained by casting is raised to 840-850℃ along with the furnace temperature, maintained for 2 hours, then raised to 1180-1210℃, and maintained for another 2 hours; the initial forging temperature is 1150-1200℃, and the final forging temperature is 850±10℃; then water cooling and air cooling are performed.
[0014] Furthermore, in S3, the heat treatment includes annealing and quenching and tempering.
[0015] Compared with the prior art, the present invention has the following beneficial effects: In the hot-rolled bearing ring processing technology of this invention, lanthanum-boron composite powder and vanadium-doped titanium dioxide are introduced simultaneously. Boron (B) in the lanthanum-boron composite powder can be adsorbed at the austenite grain boundaries, inhibiting ferrite nucleation. Lanthanum (La) in the lanthanum-boron composite powder can combine with S and O in steel to form spherical rare earth inclusions, changing the original elongated MnS morphology and improving the anisotropy of the steel. The combined effect of the two promotes finer martensite laths and improves hardenability.
[0016] More importantly, the presence of lanthanum (La) helps to purify grain boundaries and reduce adverse interfacial reactions driven by oxygen potential, thereby mitigating / weakening or even offsetting the negative impact of introducing vanadium-doped titanium dioxide to some extent. Although it is not easy to form (V,La)C solid solution, by controlling the precipitation behavior and grain boundary characteristics, it is still possible to achieve a synergistic improvement effect on hardenability. Attached Figure Description
[0017] Figure 1 This is a comparative trend chart of the hardenability test data of bearing steel round bars prepared in Example 1 and Comparative Examples 1-4 of the present invention. Figure 2 This is a comparative trend chart of the tensile strength test data of bearing steel round bars prepared in Examples 1-3 and Comparative Examples 1-4 of the present invention; Figure 3 This is a flowchart of step S4 of the hot-rolled bearing ring processing technology of the present invention, which involves heating, piercing, rolling and hot-cutting the bearing steel round bar. Detailed Implementation
[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise specified, the raw materials used in the embodiments and comparative examples of this application are all commercially available.
[0019] Example 1: (a) Preparation of vanadium-doped titanium dioxide, the preparation method is as follows: A1. Mix 0.54 g cetyltrimethylammonium bromide, 53 mL anhydrous ethanol and 11 mL deionized water, then add 10.2 mL tetrabutyl titanate, 0.95 mL acetylacetone and 0.1 g ammonium metavanadate. Stir continuously at 280 r / min for 1 h at room temperature to obtain solution one.
[0020] A2. Mix 11 mL of anhydrous ethanol and 0.65 mL of deionized water, and add concentrated nitric acid (70% by volume) dropwise to adjust the pH to 3 to obtain solution two.
[0021] A3. Add solution 2 obtained from A2 to solution 1 obtained from A1 while stirring (250 r / min) at a rate of 0.1 mL / s. After the addition is complete, continue stirring for 4 h to obtain a transparent and stable sol. After the sample gels, age it at room temperature for 10 h, then raise the temperature to 65℃ and age it for another 10 h. Finally, calcine it at 450℃ for 3 h to obtain vanadium-doped titanium dioxide.
[0022] (II) Preparation of Lanthanum-Boron Composite Powder: The preparation method is as follows: Lanthanum powder with a purity ≥ 99% (particle size ≤ 50 μm) and high-purity crystalline boron powder (average particle size 30 μm, purity 99%) are used; the lanthanum powder and boron powder are mixed at a mass ratio of 2:1 to obtain a solid powder; anhydrous ethanol is used as the dispersion medium, and the solid-liquid ratio is 1:5 (w / v) to obtain a solid-liquid mixture; 0.5% by mass of polyethylene glycol (PEG-2000) is added to the solid-liquid mixture, and ultrasonic vibration is performed for 30 min (frequency 40 kHz). Then, a ball mill is used (ball-to-material ratio 5:1) at a speed of 200 rpm for 6 h to obtain a composite powder slurry with D50 ≤ 10 μm; the composite powder slurry is dried in a vacuum oven at 60℃ for 10 h (vacuum degree ≤ -0.09 MPa) to avoid oxidation. Finally, the material is discharged and crushed by a jaw crusher, and then passed through a 200-mesh sieve to obtain the lanthanum-boron composite powder.
[0023] (III) A hot-rolled bearing ring machining process, comprising the following steps: S1. By weight, add 95.5 parts of pure iron, 1.54 parts of chromium strip and 0.5 parts of carbon block into the vacuum induction furnace. Start the vacuum pump to evacuate the furnace until the pressure inside the furnace is 1 Pa. Turn on the power and purge 50 kPa argon gas into the furnace to begin the melting stage.
[0024] S2. After melting and cleaning, add 0.48 parts of carbon blocks to the vacuum induction furnace again, evacuate the vacuum furnace, and perform carbon deoxidation. The vacuum degree is controlled at about 16 Pa, the carbon deoxidation time is 32 min, and then argon gas is introduced again at 10 kPa.
[0025] S3. Add 0.042 parts aluminum, 0.55 parts silicon, and 0.82 parts manganese to the vacuum induction furnace in S2 sequentially. After 4 minutes, measure the temperature and adjust the power to reach 1530℃. Then add 0.0155 parts rare earth cerium (metallic cerium), 0.012 parts vanadium-doped titanium dioxide, and 0.033 parts lanthanum-boron composite powder. After adding all the materials and holding at this temperature for 4 minutes, pour the mixture. Then, forge and heat treat the mixture to obtain bearing steel round bars. It is important to emphasize that when adding vanadium-doped titanium dioxide and lanthanum-boron composite powder, they should be mixed with argon gas and sprayed into the molten pool (to a depth of approximately 10 cm) through a refractory ceramic nozzle. This prevents the powdered materials from floating or agglomerating and failing to disperse evenly when directly added to the molten pool. Furthermore, it is crucial to strictly control the process to prevent the accidental introduction of titanium dioxide during the addition of vanadium-doped titanium dioxide.
[0026] The specific forging operation is as follows: the steel ingot obtained by casting is heated to 850°C along with the furnace temperature, maintained for 2 hours, then heated to 1200°C, and maintained for another 2 hours; then it is taken out of the furnace and forged directly, with a final forging temperature of 850°C, to obtain a forged bar with a diameter of 50mm; it is water-cooled in room temperature water, cooled to about 580°C, and then air-cooled at room temperature.
[0027] Heat treatment includes annealing and quenching-tempering. The specific operation for annealing is as follows: heat to 800℃, hold for 3 hours, cool to 700℃ at a rate of 30℃ / h, hold for another 4 hours, then furnace cool to 580℃, and finally air cool. The specific operation for quenching-tempering is as follows: hold at 830℃ for 30 minutes (oil quenching), then hold at 160℃ for 3 hours, and finally air cool.
[0028] S4. The bearing steel round bar is heated, pierced, rolled and hot-cut in sequence to obtain the hot-rolled bearing ring.
[0029] The S4 process is existing technology, and the specific process is as follows: Figure 3 As shown, bearing steel round bars are conveyed to a walking beam furnace for heating, and then enter the conveyor roller conveyor through the heated discharge port. The heated round bars are then fed into the piercing mill. Under the powerful rolling action of the piercing mill, the round bars move forward. At the same time, another force, which is also the most important function of tube piercing, is the push rod carriage used for tube piercing. It drives the push rod to move quickly to the outlet of the tube piercing mill and locks it. Together with the rolling force of the tube piercing mill and the reaction force of the push rod carriage, they form the resultant force of the tube piercing process to complete the piercing process.
[0030] After piercing, the mandrel carriage quickly returns to its original position, and the tube is flipped into the flipping platform by the flipping mechanism. The flipping mechanism then feeds the tube into the conveyor roller table, and the mandrel carriage immediately enters the inner hole of the tube and locks at the inlet of the tube rolling mill (first rolling mill). The tube rolling mill (first rolling mill) begins rolling, and after rolling, the mandrel carriage quickly returns to its original position. The hot-rolled tube enters the rolling mill (second rolling mill) through the conveyor roller table for sizing rolling. This section of rolling does not involve a mandrel; it is only air rolling to ensure the uniformity of the outer diameter of the steel tube.
[0031] After the second rolling, the hot-rolled pipe is immediately fed into the online hot cutting unit via conveyor rollers. The hot-rolled bearing steel pipe that has undergone two rolling processes is then hot-cut into several equal bearing ring blanks online, which are then sent to the bearing ring blank storage area via conveyor rollers.
[0032] Example 2: The difference between this example and Example 1 is that a hot-rolled bearing ring processing technology includes the following steps: S1. By weight, add 95.3 parts of pure iron, 1.5 parts of chromium strip and 0.48 parts of carbon block to the vacuum induction furnace, start the vacuum pump to evacuate the vacuum induction furnace, and set the pressure inside the vacuum induction furnace to 1 Pa. Turn on the power and purge 50 kPa argon gas into the vacuum induction furnace to begin the melting stage.
[0033] S2. After melting and cleaning, add 0.45 parts of carbon blocks to the vacuum induction furnace again, evacuate the vacuum furnace, and perform carbon deoxidation. The vacuum degree is controlled at about 16 Pa, and the carbon deoxidation time is 32 min. Then, argon gas is introduced again at 10 kPa.
[0034] S3. Add 0.04 parts of aluminum block, 0.5 parts of silicon block, and 0.8 parts of manganese block to the vacuum induction furnace of S2 in sequence. After 4 minutes, measure the temperature and adjust the power to reach 1530℃. Add 0.015 parts of rare earth cerium, 0.011 parts of vanadium-doped titanium dioxide, and 0.03 parts of lanthanum-boron composite powder. Then, hold the temperature for 4 minutes and cast the material. After forging and heat treatment, the bearing steel round bar material is obtained.
[0035] S4. The bearing steel round bar is heated, pierced, rolled and hot-cut in sequence to obtain the hot-rolled bearing ring.
[0036] Example 3: The difference between this example and Example 1 is that a hot-rolled bearing ring processing method includes the following steps: S1. By weight, add 95.8 parts of pure iron, 1.6 parts of chromium strip and 0.52 parts of carbon block to the vacuum induction furnace, start the vacuum pump to evacuate the vacuum induction furnace, and set the pressure inside the vacuum induction furnace to 1 Pa. Turn on the power and purge 50 kPa argon gas into the vacuum induction furnace to begin the melting stage.
[0037] S2. After melting and cleaning, add 0.5 parts of carbon blocks to the vacuum induction furnace again, evacuate the vacuum furnace, and perform carbon deoxidation. The vacuum degree is controlled at about 16 Pa, and the carbon deoxidation time is 32 min. Then, argon gas is introduced again at 10 kPa.
[0038] S3. Add 0.045 parts of aluminum block, 0.6 parts of silicon block, and 0.85 parts of manganese block to the vacuum induction furnace of S2 in sequence. After 4 minutes, measure the temperature and adjust the power to reach 1530℃. Add 0.016 parts of rare earth cerium, 0.013 parts of vanadium-doped titanium dioxide, and 0.035 parts of lanthanum-boron composite powder. Then, hold the temperature for 4 minutes and cast the material. After forging and heat treatment, the bearing steel round bar material is obtained.
[0039] S4. The bearing steel round bar is heated, pierced, rolled and hot-cut in sequence to obtain the hot-rolled bearing ring.
[0040] Comparative Example 1: The difference between this comparative example and Example 1 is that: in the hot rolling and cutting of bearing rings, vanadium-doped titanium dioxide and lanthanum-boron composite powder are not added; and the amount of rare earth cerium added is reduced from 0.0155 parts to 0.008 parts.
[0041] Specifically, a hot-rolled bearing ring machining process includes the following steps: S1. By weight, add 95.5 parts of pure iron, 1.54 parts of chromium strip and 0.5 parts of carbon block to the vacuum induction furnace, start the vacuum pump to evacuate the vacuum induction furnace, and set the pressure inside the vacuum induction furnace to 1 Pa. Turn on the power and purge 50 kPa argon gas into the vacuum induction furnace to begin the melting stage.
[0042] S2. After melting and cleaning, add 0.48 parts of carbon blocks to the vacuum induction furnace again, evacuate the vacuum furnace, and perform carbon deoxidation. The vacuum degree is controlled at about 16 Pa, the carbon deoxidation time is 32 min, and then argon gas is introduced again at 10 kPa.
[0043] S3. Add 0.042 parts of aluminum block, 0.55 parts of silicon block, and 0.82 parts of manganese block to the vacuum induction furnace of S2 in sequence. After 4 minutes, measure the temperature and adjust the power to reach 1530℃. Add 0.008 parts of rare earth cerium, and then keep it at the temperature for 4 minutes before casting. After forging and heat treatment in sequence, the bearing steel round bar material is obtained.
[0044] S4. The bearing steel round bar is heated, pierced, rolled and hot-cut in sequence to obtain the hot-rolled bearing ring.
[0045] Comparative Example 2: The difference between this comparative example and Example 1 is that no vanadium-doped titanium dioxide and lanthanum-boron composite powder are added in the hot rolling and cutting process of bearing rings.
[0046] Comparative Example 3: The difference between this comparative example and Example 1 is that no lanthanum-boron composite powder is added in the hot rolling and cutting process of bearing rings.
[0047] Comparative Example 4: The difference between this comparative example and Example 1 is that no vanadium-doped titanium dioxide is added in the hot rolling and cutting process of bearing rings.
[0048] Test Example: Test Subjects: Bearing steel round bar samples prepared in Examples 1-3 and Comparative Examples 1-4. Test Items and Methods: ① Hardenability Test - conducted according to "GB / T225-2006 End-Quenching Test Method (Jominy Test) for Hardenability of Steel"; ② Tensile Strength Test - conducted according to "GB / T228.1-2010 Metallic Materials - Tensile Testing - Part 1: Test at Room Temperature". Test Results: See Tables 1 and 2.
[0049] Table 1. Hardenability Test Data (HRC)
[0050] Table 2. Tensile strength test data (MPa)
[0051] Results Analysis: Combining the data in Table 1 and Table 2, and Figure 1 , Figure 2 Analysis of Examples 1-3 shows that the bearing steel round bars prepared by the present invention (Examples 1-3) have excellent hardenability and tensile strength test data of up to 2242.4 MPa or more.
[0052] Combining the data in Table 1 and Table 2 and Figure 1 , Figure 2 The analysis focused on Example 1 and Comparative Examples 1-4: Specifically, comparing Comparative Example 1 and Comparative Example 2, it can be seen that compared to 0.008 parts of rare earth cerium added in Comparative Example 1, the addition of rare earth cerium in Comparative Example 2 increased to 0.0155 parts. As a result, the tensile strength test data of the bearing steel round bar material increased from 2105.5 MPa (Comparative Example 1) to 2293.8 MPa (Comparative Example 2). However, the hardenability (hardened layer depth) decreased. This indicates that increasing the addition of rare earth cerium (0.008 parts → 0.0155 parts) can improve the tensile strength of the bearing steel round bar material, but it also leads to a decrease in its hardenability (hardened layer depth).
[0053] Specifically, comparing Comparative Examples 2 and 3, it can be seen that, compared to Comparative Example 2, the addition of vanadium-doped titanium dioxide alone in Comparative Example 3 resulted in a decrease in the hardenability (hardened layer depth) of the bearing steel round bars. This is mainly because, when vanadium-doped titanium dioxide is added alone, the vanadium is tightly bound to TiO2, making it difficult to reduce and precipitate VC under conventional smelting conditions. Instead, its inertness can lead to the accumulation of local inclusions, deteriorating the material purity. At the same time, unmelted TiO2 particles may also hinder carbon diffusion, further reducing hardenability.
[0054] Specifically, by comparing Comparative Example 2 and Comparative Example 4, it can be seen that, compared with Comparative Example 2, the addition of lanthanum-boron composite powder in Comparative Example 4 alone improved the hardenability (hardened layer depth) of the bearing steel round bar material.
[0055] Comparing with Example 1, it can be seen that the simultaneous introduction of vanadium-doped titanium dioxide and lanthanum-boron composite powder produces a synergistic effect, jointly improving the hardenability (hardened layer depth) of the prepared bearing steel round bar. Although it also leads to a decrease in tensile strength, the reduction is very limited.
[0056] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A hot-rolled bearing ring machining process, characterized in that, Includes the following steps: S1. By weight, add 95.3-95.8 parts of pure iron, 1.5-1.6 parts of chromium strips and 0.48-0.52 parts of carbon blocks to the vacuum induction furnace, evacuate to a pressure ≤1Pa, introduce argon gas, and melt. S2. After melting and cleaning, add 0.45-0.5 parts of carbon blocks to the vacuum induction furnace, evacuate the vacuum furnace, and perform carbon deoxidation. The vacuum degree is controlled at 13-18 Pa, and the carbon deoxidation time is 30-35 min. Then, argon gas is introduced again. S3. Add 0.04-0.045 parts of aluminum block, 0.5-0.6 parts of silicon block, and 0.8-0.85 parts of manganese block to a vacuum induction furnace in sequence. When the temperature reaches 1500-1540℃, add 0.015-0.016 parts of rare earth cerium, 0.011-0.013 parts of vanadium-doped titanium dioxide, and 0.03-0.035 parts of lanthanum-boron composite powder. After holding at the temperature for 3-5 minutes, pour the mixture and then forge and heat treat it in sequence to obtain bearing steel round bars. S4. The bearing steel round bar obtained in S3 is subjected to heating, piercing, rolling and hot cutting processes in sequence to obtain the hot-rolled and cut bearing ring.
2. The hot-rolled bearing ring processing technology according to claim 1, characterized in that, The preparation method of the vanadium-doped titanium dioxide is as follows: A1. Mix 0.54 g cetyltrimethylammonium bromide, 52-55 mL anhydrous ethanol and 10-12 mL deionized water, then add 10-10.5 mL tetrabutyl titanate, 0.9-1 mL acetylacetone and 0.1 g ammonium metavanadate, stir at room temperature to obtain solution one; A2. Mix 10.5-11.5 mL of anhydrous ethanol and 0.6-0.7 mL of deionized water, and adjust the pH to 3 ± 0.05 by adding concentrated nitric acid dropwise to obtain solution two; A3. Add the solution obtained from A2 to the solution obtained from A1 while stirring, and continue stirring to obtain a sol; after gelation, age and calcine to obtain the final product.
3. The hot-rolled bearing ring processing technology according to claim 2, characterized in that, In A3, the specific aging process is as follows: first age at room temperature for 9.5-11 hours, then age at 65±2℃ for 9.5-11 hours.
4. The hot-rolled bearing ring processing technology according to claim 2, characterized in that, In A3, the calcination temperature is 450±10℃ and the calcination time is 3-3.2h.
5. The hot-rolled bearing ring processing technology according to claim 1, characterized in that, The lanthanum-boron composite powder comprises lanthanum powder and boron powder, and the mass ratio of the two is 2:
1.
6. The hot-rolled bearing ring processing technology according to claim 1 or 5, characterized in that, The lanthanum-boron composite powder is prepared by mixing lanthanum powder and boron powder, dispersing them in anhydrous ethanol dispersion medium by ball milling for 5-6 hours, and then drying under vacuum.
7. The hot-rolled bearing ring processing technology according to claim 6, characterized in that, The specific washing procedure is as follows: the drying temperature is 60±2℃, and the drying time is 9-12 hours.
8. The hot-rolled bearing ring processing technology according to claim 1, characterized in that, In S3, the initial forging temperature is 1150-1200℃, and the final forging temperature is 850±10℃.
9. The hot-rolled bearing ring processing technology according to claim 1, characterized in that, In S3, heat treatment includes annealing and quenching and tempering.