Fine regulation and control method for high-strength and high-toughness martensite-bainite complex-phase structure of high-carbon steel bearing

Abstract

The invention provides a fine regulation and control method for a high-strength and high-toughness martensite-bainite complex-phase structure of a high-carbon steel bearing, and relates to the technical field of bearing manufacturing. The method comprises the following steps: acquiring austenite grain size process parameters and austenite carbon content process parameters in response to Martensite-Beta complex phase fine regulation and control operation for a target bearing; based on the austenitizing process parameters, the corresponding austenitizing heat preservation temperature and austenitizing heat preservation time when the target bearing meets the preset process conditions are calculated; carrying out austenitizing process treatment on the target bearing according to the austenitizing heat preservation temperature and the austenitizing heat preservation time; and the target bearing subjected to austenitizing process treatment is subjected to toughness performance optimization treatment, and a martensite-bainite complex phase structure corresponding to the target bearing is obtained through the toughness performance optimization treatment. The method solves the problem that if the isothermal quenching temperature is blindly increased in order to pursue a short inoculation period and a high nucleation rate, a lath structure is extremely likely to be coarsened and combined, and therefore the performance is degraded.

Description

Technical Field

[0001] The present application relates to the field of bearing manufacturing technology, and in particular to a method for finely controlling the high-strength and high-toughness Mapei complex phase structure of a high-carbon steel bearing. Background Art

[0002] GCr15 steel is the most widely used bearing steel. Due to its low alloy content and high carbon content, it can obtain a structure with high hardness, strength and wear resistance after conventional martensite quenching and tempering, and is widely used in the bearing field. As a key component with a slewing support function, bearings have an irreplaceable position in the fields of aerospace, automobiles, ships, etc. With the continuous development of high-end machine tools, new energy vehicles and other fields, it is difficult for GCr15 bearings with traditional structures to maintain a high fatigue life in the current service environment of high speed, high load, impact load, etc. How to further improve the fatigue life by improving the toughness of GCr15 bearings has become a research problem in the bearing manufacturing industry.

[0003] In order to improve the strength-toughness matching of GCr15, the Mapei multiphase heat treatment process is often used to introduce bainite under the toughness phase. However, the existing multiphase heat treatment only obtains a multiphase structure including martensite and bainite. During the composite heat treatment process, there is no reasonable and effective control of the high-temperature austenite, martensite and bainite microstructure states, resulting in the failure to achieve the optimal effect on improving the strength and toughness of the bearing steel.

[0004] Therefore, there is an urgent need for a method to finely control the high-strength and high-toughness Mapei complex phase structure of high-carbon steel bearings. Summary of the invention

[0005] The present application provides a method for finely controlling the high-strength and high-toughness Mapei composite structure of high-carbon steel bearings, which solves the problem that the existing composite heat treatment does not reasonably and effectively control the high-temperature austenite, martensite and bainite microstructures during the composite heat treatment process, resulting in the failure to achieve the optimal effect in improving the strength and toughness of the bearing steel.

[0006] In a first aspect of the present application, a method for fine-tuning the high-strength and high-toughness Mapei complex phase structure of a high-carbon steel bearing is provided, the method comprising: in response to the Mapei complex phase fine-tuning operation for a target bearing, obtaining austenitizing process parameters, the austenitizing process parameters comprising austenite grain size process parameters and austenite carbon content process parameters; based on the austenitizing process parameters, calculating the austenitizing holding temperature and austenitizing holding time corresponding to the target bearing when the preset process conditions are met; performing an austenitizing process treatment on the target bearing according to the austenitizing holding temperature and the austenitizing holding time; performing strength and toughness optimization treatment on the target bearing after the austenitizing process treatment in a preset execution order, the strength and toughness optimization treatment comprising a pre-quenching process operation and an isothermal quenching process operation, the execution order of the pre-quenching process operation being before the isothermal quenching process operation; through the strength and toughness optimization treatment, the martensite-bainite complex phase structure corresponding to the target bearing is obtained.

[0007] Optionally, the preset process conditions include a first preset condition, and based on the austenitizing process parameters, the austenitizing insulation temperature corresponding to the target bearing when the preset process conditions are met is calculated, specifically including: according to the following formula, the austenitizing insulation temperature of the target bearing when the first preset condition is met, and the first preset condition is that the austenite grain size of the target bearing is less than or equal to the preset size.

[0008]

[0009] Wherein, D is the austenite grain size process parameter, A is a constant, and in the range of 800-1050°C, A can be 2.248×10 16 , R is the ideal gas constant, Q A is the activation free energy of austenite transformation, T A The austenitizing holding temperature

[0010] Optionally, the preset process conditions also include a second set condition, based on the austenitizing process parameters, calculating the austenitizing holding time corresponding to the target bearing when the preset process conditions are met, specifically including: calculating the austenitizing holding time of the target bearing when the second set condition is met according to the following formula, the second set condition being that the mass fraction of carbon element of the target bearing is less than or equal to a preset percentage:.

[0011]

[0012] Among them, t A is the austenitizing holding time, X θis the expected value corresponding to the austenite carbon content process parameter, X0 is the initial value corresponding to the austenite carbon content process parameter, and β is a constant.

[0013] Optionally, the target bearing after the austenitizing process is subjected to strength and toughness optimization treatment according to a preset execution order, wherein the pre-quenching process operation is performed on the target bearing, specifically including: obtaining first quenching martensite volume fraction data; based on the first quenching martensite volume fraction data, calculating the pre-quenching temperature and pre-quenching time of the target bearing when a third preset condition is met, wherein the third preset condition is to control the first quenching martensite volume fraction data to be within a first preset volume fraction range; and performing the pre-quenching process operation on the target bearing according to the pre-quenching temperature and the pre-quenching time.

[0014] Optionally, the obtaining of the first quenched martensite volume fraction data specifically includes: calculating the first quenched martensite volume fraction data according to the following formula:

[0015] f M =1-6.956×10 -15 (455-ΔT) 5.32 ;

[0016] Among them, f M is the first quenched martensite volume fraction data, and ΔT is the difference between the martensite start transformation temperature and the pre-quenching temperature.

[0017] Optionally, the target bearing after the austenitizing process is subjected to strength and toughness optimization treatment according to a preset execution order, wherein the target bearing is subjected to the isothermal quenching process, specifically comprising: obtaining second quenching martensite volume fraction data and bainite volume fraction data, and calculating the isothermal quenching temperature and isothermal quenching time of the target bearing when a fourth preset condition is met, wherein the fourth preset condition is to control the second quenching martensite volume fraction data to be within a second preset volume fraction interval, and to control the bainite volume fraction data to be within a third preset volume fraction interval; and performing the strength and toughness optimization treatment according to the isothermal quenching temperature and the isothermal quenching time.

[0018] Optionally, calculating the isothermal quenching temperature of the target bearing when the fourth preset condition is met specifically includes: acquiring bainite nucleation density data, and calculating the isothermal quenching temperature based on the bainite nucleation density data by the following formula:

[0019]

[0020] Among them, T B is the austempering temperature, Nm is the bainite nucleation density data, V m is a constant, M s is the martensitic transformation starting temperature data.

[0021] Optionally, calculating the isothermal quenching time of the target bearing when the fourth preset condition is met specifically includes: acquiring bainite phase transformation activation energy data, and calculating the isothermal quenching time based on the bainite phase transformation activation energy data by the following formula:

[0022]

[0023] Among them, t B is the austempering time, f B is the bainite volume fraction data, C1 and C2 are both constants, is the activation energy data of the bainite phase transformation, R is the ideal gas constant, T B is the isothermal quenching temperature.

[0024] Optionally, the obtaining of the second quenched martensite volume fraction data specifically includes: calculating the second quenched martensite volume fraction data according to the following formula:

[0025] f AM =1-f M -f B -f γ -f C ;

[0026] Among them, f AM is the volume fraction data of the second quenched martensite, f M is the volume fraction data of the first quenched martensite, f B is the bainite volume fraction data, f γ is the volume fraction of retained austenite, and its value can be 3% to 8%, f C It is the volume fraction of undissolved carbides and can be between 5% and 10%.

[0027] Optionally, the martensite-bainite multiphase structure corresponding to the target bearing is obtained by the strength and toughness optimization processing, specifically including: obtaining bainite average lath size data, and under the fifth preset condition, obtaining the martensite-bainite multiphase structure corresponding to the target bearing by the strength and toughness optimization processing, the fifth preset condition being that the bainite average lath size data is less than or equal to the preset size.

[0028] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0029] 1. When the user performs Mapei multiphase fine-tuning operation on the target bearing, in response to the Mapei multiphase fine-tuning operation on the target bearing, the austenite grain size process parameters and the austenite carbon content process parameters are obtained; based on the austenitizing process parameters, the austenitizing holding temperature and austenitizing holding time corresponding to the target bearing when the preset process conditions are met are calculated; the target bearing is austenitized according to the austenitizing holding temperature and the austenitizing holding time; the target bearing after the austenitizing is subjected to strength and toughness optimization treatment, and the martensite-bainite multiphase structure corresponding to the target bearing is obtained through the strength and toughness optimization treatment, thereby solving the problem that the existing multiphase heat treatment does not reasonably and effectively control the high-temperature austenite, martensite and bainite microstructure states during the composite heat treatment process, resulting in the failure to achieve the optimal effect of improving the strength and toughness of the bearing steel, thereby greatly optimizing the strength and toughness matching, wear resistance and fatigue life of the bearing material.

[0030] 2. By controlling the pre-quenching temperature and controlling the first pre-quenching martensite volume fraction to meet the third preset condition, bainite nucleation can be promoted and space can be reserved for bainite growth.

[0031] 3. By obtaining the second quenching martensite volume fraction data and the bainite volume fraction data, and calculating the isothermal quenching temperature and the isothermal quenching time of the target bearing when the fourth preset condition is met, the first quenching martensite volume fraction data, the second quenching martensite volume fraction data and the bainite volume fraction data are respectively controlled in the corresponding volume fraction ranges, thereby achieving optimal matching of strength and toughness properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of a process for finely controlling the high-strength and high-toughness Mapei complex phase structure of a high-carbon steel bearing provided in an embodiment of the present application;

[0033] Figure 2 This is a schematic diagram of temperature change of Mapei complex phase strength and toughness optimization for high carbon steel bearings provided in an embodiment of the present application;

[0034] Figure 3 It is a schematic diagram comparing the tensile and impact performance regulation effect provided in the embodiment of the present application with the traditional martensitic quenching and tempering process. DETAILED DESCRIPTION

[0035] In order to enable technicians in this field to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments.

[0036] The terms used in the following embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to be used as limitations to the present application. As used in the specification of the present application, the singular expressions "one", "a kind of", "said", "above", "the" and "this" are intended to also include plural expressions, unless there is a clear indication to the contrary in the context. It should also be understood that the term "and / or" used in the present application refers to and includes any or all possible combinations of one or more listed items.

[0037] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features, and in the description of the embodiments of the present application, unless otherwise specified, "plurality" means two or more.

[0038] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0039] Please refer to Figure 1 , which shows a schematic flow chart of a method for finely controlling the high-strength and high-toughness Mapei complex phase structure of a high-carbon steel bearing provided in an embodiment of the present application, and the flow chart mainly includes the following steps: S101 to S105.

[0040] Step S101, in response to the Mapei multiphase fine control operation for the target bearing, obtaining austenitizing process parameters, wherein the austenitizing process parameters include austenite grain size process parameters and austenite carbon content process parameters.

[0041] Specifically, when the user responds to the Mapei complex phase fine control operation for the target bearing, the austenitizing process parameters are obtained, and the austenitizing process parameters include austenite grain size process parameters and austenite carbon content process parameters. That is, in order to ensure the rapid nucleation and growth of bainite in the subsequent heat treatment process, the high-temperature austenite of the target bearing needs to satisfy the requirements of fine grains and controllable carbon content. In addition, it is also necessary to fully consider the promoting effect of rolling deformation on carbide dissolution and the inhibitory effect on grain growth. The present invention calculates the grain size process parameters and austenite carbon content process parameters obtained by the target bearing with a rolling deformation of ε after different isothermal quenching temperatures and quenching times according to the formula, and finally determines the austenitizing process that satisfies the grain size process parameters ≤10μm and the austenite carbon content process parameters ≤0.6%.

[0042] Step S102, based on the austenitizing process parameters, calculating the austenitizing holding temperature and austenitizing holding time corresponding to the target bearing when the preset process conditions are met.

[0043] Specifically, the austenitizing holding temperature of the target bearing when the first preset condition is met is calculated according to the following formula, and the first preset condition is that the austenite grain size of the target bearing is less than or equal to a preset size.

[0044]

[0045] Wherein, D is the austenite grain size process parameter, A is a constant, and in the range of 800-1050°C, A can be 2.248×10 16 , R is the ideal gas constant, Q A is the activation free energy of austenite transformation, T A is the austenitizing holding temperature;

[0046] According to the following formula, the austenitizing holding time of the target bearing when the second set condition is met is calculated, and the second set condition is that the mass fraction of the carbon element of the target bearing is less than or equal to the preset percentage:.

[0047]

[0048] Among them, t A is the austenitizing holding time, X θ is the expected value corresponding to the austenite carbon content process parameter, X0 is the initial value corresponding to the austenite carbon content process parameter, and β is a constant.

[0049] Step S103, performing an austenitizing process on the target bearing according to the austenitizing holding temperature and the austenitizing holding time.

[0050] Step S104, performing strength and toughness optimization processing on the target bearing after the austenitizing process according to a preset execution order.

[0051] Specifically, a strong and toughness optimization treatment is used to achieve efficient bainite phase transformation. The strong and toughness optimization treatment includes a pre-quenching process operation and an isothermal quenching process operation. The execution order of the pre-quenching process operation is before the isothermal quenching process operation.

[0052] In a possible embodiment, step S104 also includes: obtaining first quenching martensite volume fraction data; based on the first quenching martensite volume fraction data, calculating the pre-quenching temperature and pre-quenching time of the target bearing when a third preset condition is met, wherein the third preset condition is to control the first quenching martensite volume fraction data to be within a first preset volume fraction range; and performing the pre-quenching process operation on the target bearing according to the pre-quenching temperature and the pre-quenching time.

[0053] Specifically, by controlling the pre-quenching temperature and controlling the first pre-quenching martensite volume fraction to meet the third preset condition, that is, controlling the first pre-quenching martensite volume fraction to be between 5% and 15%, bainite nucleation can be promoted and space can be reserved for bainite growth. The pre-quenching temperature and pre-quenching time of the target bearing when the third preset condition is met are calculated, and the first quenching martensite volume fraction data is calculated according to the following formula:

[0054] f M =1-6.956×10 -15 (455-ΔT) 5.32 ;

[0055] Among them, f M is the first quenched martensite volume fraction data, and ΔT is the difference between the martensite start transformation temperature and the pre-quenching temperature.

[0056] In a possible implementation, step S104 also includes: acquiring second quenching martensite volume fraction data and bainite volume fraction data, and calculating the isothermal quenching temperature and isothermal quenching time of the target bearing when a fourth preset condition is met, wherein the fourth preset condition is to control the second quenching martensite volume fraction data to be in a second preset volume fraction interval, and to control the bainite volume fraction data to be in a third preset volume fraction interval; performing the strength and toughness optimization processing according to the isothermal quenching temperature and the isothermal quenching time.

[0057] Specifically, the second quenching martensite volume fraction data and the bainite volume fraction data are obtained, and the isothermal quenching temperature and the isothermal quenching time of the target bearing when the fourth preset condition is met are calculated, that is, the first quenching martensite volume fraction data, the second quenching martensite volume fraction data and the bainite volume fraction data are respectively controlled in the corresponding volume fraction intervals, so as to achieve the optimal matching of strength and toughness, wherein the volume fraction interval corresponding to the first quenching martensite volume fraction data is 10% to 15%, the volume fraction interval corresponding to the first quenching martensite volume fraction data is 30% to 35%, and the volume fraction interval corresponding to the bainite volume fraction data is 40% to 45%. The bainite nucleation density data is obtained, and based on the bainite nucleation density data, the isothermal quenching temperature is calculated by the following formula:

[0058]

[0059] Among them, T B is the austempering temperature, N m is the bainite nucleation density data, V m is a constant, M sis the martensitic transformation starting temperature data. Obtain bainitic transformation activation energy data, and based on the bainitic transformation activation energy data, calculate the isothermal quenching time by the following formula:

[0060]

[0061] Among them, t B is the austempering time, f B is the bainite volume fraction data, C1 and C2 are both constants, is the activation energy data of the bainite phase transformation, R is the ideal gas constant, T B is the austempering temperature. The second quenching martensite volume fraction data is calculated according to the following formula:

[0062] f AM =1-f M -f B -f γ -f C ;

[0063] Among them, f AM is the volume fraction data of the second quenched martensite, f M is the volume fraction data of the first quenched martensite, f B is the bainite volume fraction data, f γ is the volume fraction of retained austenite, and its value can be 3% to 8%, f C It is the volume fraction of undissolved carbides and can be between 5% and 10%.

[0064] Step S105, obtaining a martensite-bainite multiphase structure corresponding to the target bearing through the strength and toughness optimization process.

[0065] Specifically, please refer to Figure 2 , which shows a schematic diagram of temperature change of Mapei complex phase strength and toughness optimization for high carbon steel bearings provided in an embodiment of the present application.

[0066] In a possible embodiment, step S105 also includes: obtaining average bainite lath size data, and obtaining the martensite-bainite multiphase structure corresponding to the target bearing through the strength and toughness optimization processing under the fifth preset condition, and the fifth preset condition is that the average bainite lath size data is less than or equal to the preset size.

[0067] Specifically, in order to finely control the size of the bainite lath, the upper limit of the isothermal time under the fifth preset condition is calculated based on the following formula:

[0068]

[0069] Among them, l B is the average lath size data of bainite, V0 is the pre-exponential factor, and V0 = 30 m / s, k is the Boltzmann constant, and k = 1.380649 × 10 -23 J / K.

[0070] Taking a certain type of high-speed machine tool bearing ring made of GCr15 as an example, its initial microstructure is in the spheroidized annealing state. The fine control of its high-strength and high-toughness Mapei multiphase microstructure is achieved by the following steps:

[0071] S1. Austenitizing process parameter control: The bearing ring is austenitized in a vacuum atmosphere furnace, and the bearing is heated to 845°C for 20 minutes.

[0072] S2. Control of pre-quenching process parameters: A constant temperature salt bath furnace is used for temperature-controlled pre-quenching. The quenching medium is 45% sodium nitrite + 55% potassium nitrate. The pre-quenching process parameters are finally determined to be 200°C / 5min.

[0073] S3. Isothermal quenching process parameter control: A constant temperature salt bath furnace is used for isothermal quenching, and the quenching medium is 45% sodium nitrite + 55% potassium nitrate. The isothermal quenching process parameters are finally determined to be 200℃ / 5min. After the isothermal quenching is completed, it is transferred to a constant temperature oil bath furnace for martensite final quenching. The quenching medium is QJ22-32 high-speed bright quenching oil, and the quenching temperature is 70℃.

[0074] After fine-tuning the high-strength and high-toughness Mapei multiphase structure, the volume fractions of the first-stage quenched martensite, bainite, and second-stage quenched martensite were 13.6%, 54.3%, and 27.5%, respectively, and the organizational proportions met the control target. In addition, the average lath width was 0.39μm, indicating that the Mapei multiphase structure was effectively refined.

[0075] Please refer to Figure 3 , which shows a schematic diagram of the comparison between the tensile and impact performance regulation effect provided by the embodiment of the present application and the traditional martensite quenching and tempering process. Through the standard U-notch Charpy impact test, the impact absorption energy is increased from 6.8J to 12.3J, and the impact absorption energy is increased by about 80%. In the traditional process, cracks quickly expand in large pieces of martensite, and the contour is relatively straight. This technology greatly increases the multiphase interface in the matrix, and the content of hard and brittle martensite is also significantly reduced, and the crack propagation path becomes very tortuous. The embodiment shows that the use of the present invention can significantly optimize the strength and toughness matching of GCr15 bearings.

[0076] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0077] In the several embodiments provided in this application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are only schematic, such as the division of units, which is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some service interfaces, and the indirect coupling or communication connection of devices or units can be electrical or other forms.

[0078] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0079] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0080] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a memory and includes several instructions for a computer device (which can be a personal computer, server or network device, etc.) to perform all or part of the steps of the various embodiments of the present application. The aforementioned memory includes: various media that can store program codes, such as USB flash drives, mobile hard drives, magnetic disks or optical disks.

[0081] The above are only exemplary embodiments disclosed in this application, and the scope of the disclosure of this application cannot be limited by this. That is, any equivalent changes and modifications made according to the teachings disclosed in this application are still within the scope of the disclosure of this application. After considering the disclosure of the specification and the truth of practice, those skilled in the art will easily think of other implementation schemes disclosed in this application.

[0082] This application is intended to cover any modifications, uses or adaptive changes disclosed in this application, which follow the general principles disclosed in this application and include common knowledge or customary technical means in the technical field not recorded in this application.

Claims

1. A method for finely controlling the high-strength and high-toughness Mapei complex phase structure of a high-carbon steel bearing, characterized in that: The method comprises: In response to the Mapei multiphase fine-tuning operation for the target bearing, obtaining austenitizing process parameters, the austenitizing process parameters including austenite grain size process parameters and austenite carbon content process parameters; Based on the austenitizing process parameters, calculating the austenitizing holding temperature and austenitizing holding time corresponding to the target bearing when the preset process conditions are met; Performing an austenitizing process on the target bearing according to the austenitizing holding temperature and the austenitizing holding time; According to a preset execution order, the target bearing after the austenitizing process is subjected to a strength and toughness optimization process, wherein the strength and toughness optimization process includes a pre-quenching process operation and an isothermal quenching process operation, and the execution order of the pre-quenching process operation is before the isothermal quenching process operation; Through the strength and toughness optimization process, a martensite-bainite multiphase structure corresponding to the target bearing is obtained.

2. The method according to claim 1, characterized in that The preset process conditions include a first preset condition, and based on the austenitizing process parameters, calculating the austenitizing holding temperature corresponding to the target bearing when the preset process conditions are met, specifically including: The austenitizing holding temperature of the target bearing when the first preset condition is met is calculated according to the following formula, where the first preset condition is that the austenite grain size of the target bearing is less than or equal to a preset size: Wherein, D is the austenite grain size process parameter, A is a constant, and in the range of 800-1050°C, A can be 2.248×10 16 , R is the ideal gas constant, Q A is the activation free energy of austenite transformation, T A is the austenitizing holding temperature.

3. The method according to claim 1, characterized in that The preset process conditions also include a second set condition, based on the austenitizing process parameters, calculating the austenitizing holding time corresponding to the target bearing when the preset process conditions are met, specifically including: The austenitizing holding time of the target bearing when the second setting condition is met is calculated according to the following formula, where the second setting condition is that the mass fraction of the carbon element of the target bearing is less than or equal to a preset percentage: Among them, t A is the austenitizing holding time, X θ is the expected value corresponding to the austenite carbon content process parameter, X0 is the initial value corresponding to the austenite carbon content process parameter, and β is a constant.

4. The method according to claim 1, characterized in that: According to the preset execution order, the target bearing after the austenitizing process is subjected to the strength and toughness optimization process, wherein the target bearing is subjected to the pre-quenching process operation, specifically including: Acquire the first quenching martensite volume fraction data; Based on the first quenched martensite volume fraction data, calculating the pre-quenching temperature and pre-quenching time of the target bearing when a third preset condition is met, wherein the third preset condition is to control the first quenched martensite volume fraction data to be within a first preset volume fraction interval; The pre-quenching process operation is performed on the target bearing according to the pre-quenching temperature and the pre-quenching time.

5. The method according to claim 4, characterized in that The obtaining of the first quenched martensite volume fraction data specifically includes: The first quenched martensite volume fraction data is calculated according to the following formula: f M =1-6.956×10 -15 (455-ΔT) 5.32 ; Among them, f M is the first quenched martensite volume fraction data, and ΔT is the difference between the martensite start transformation temperature and the pre-quenching temperature.

6. The method according to claim 1, characterized in that According to the preset execution order, the target bearing after the austenitizing process is subjected to the strength and toughness optimization process, wherein the target bearing is subjected to the isothermal quenching process operation, specifically including: Acquire the second quenched martensite volume fraction data and the bainite volume fraction data, and calculate the austempering temperature and the austempering time of the target bearing when a fourth preset condition is satisfied, wherein the fourth preset condition is to control the second quenched martensite volume fraction data to be within a second preset volume fraction interval, and to control the bainite volume fraction data to be within a third preset volume fraction interval; The strength and toughness optimization treatment is performed according to the austempering temperature and the austempering time.

7. The method according to claim 6, characterized in that Calculating the isothermal quenching temperature of the target bearing when the fourth preset condition is met specifically includes: Obtain bainite nucleation density data, and based on the bainite nucleation density data, calculate the austempering temperature by the following formula: Among them, T B is the austempering temperature, N m is the bainite nucleation density data, V m is a constant, M s is the martensitic transformation starting temperature data.

8. The method according to claim 6, characterized in that Calculating the isothermal quenching time of the target bearing when the fourth preset condition is met specifically includes: Obtain bainite phase transformation activation energy data, and based on the bainite phase transformation activation energy data, calculate the austempering time by the following formula: Among them, t B is the austempering time, f B is the bainite volume fraction data, C1 and C2 are both constants, is the activation energy data of the bainite phase transformation, R is the ideal gas constant, T B is the isothermal quenching temperature.

9. The method according to claim 6, characterized in that The obtaining of the second quenched martensite volume fraction data specifically includes: The second quenched martensite volume fraction data is calculated according to the following formula: f AM =1-f M -f B -f γ -f C ; Among them, f AM is the volume fraction data of the second quenched martensite, f M is the volume fraction data of the first quenched martensite, f B is the bainite volume fraction data, f γ is the volume fraction of retained austenite, and its value can be 3% to 8%, f C It is the volume fraction of undissolved carbides and can be between 5% and 10%.

10. The method according to claim 1, characterized in that The method of obtaining a martensite-bainite multiphase structure corresponding to the target bearing through the strength and toughness optimization process specifically includes: The average lath size data of bainite is obtained, and under the fifth preset condition, the martensite-bainite multiphase structure corresponding to the target bearing is obtained through the strength and toughness optimization processing, and the fifth preset condition is that the average lath size data of bainite is less than or equal to the preset size.

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