Composite shot peening process parameter optimization method and system for optimizing tooth surface residual stress of spiral bevel gear and storage medium

Abstract

The invention discloses a composite shot peening process parameter optimization method and system for optimizing spiral bevel gear tooth surface residual stress and a storage medium, and relates to the technical field of shot peening process parameter optimization. Comprising the following steps: performing finite element analysis on a tooth surface of a target spiral bevel gear to obtain tooth surface geometric parameters such as tooth height, normal modulus and spiral angle, material mechanical property parameters such as elastic modulus, Poisson's ratio and yield strength, and surface quality parameters such as roughness and surface hardness; by calculating a surface strengthening demand coefficient, a strengthening uniformity coefficient and a surface impact energy coefficient, composite shot blasting core parameters (shot blasting pressure, speed and coverage rate) are corrected. And in combination with environment parameters such as tooth surface temperature and environment humidity, thermal environment enhancement factors are calculated, impact laser power is dynamically corrected, composite shot blasting is executed after an accurate value is obtained, technological parameter optimization is achieved, the strengthening effect of the spiral bevel gear tooth surface is improved, and the fatigue life of the spiral bevel gear tooth surface is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of optimizing shot peening process parameters, and specifically to a method, system and storage medium for optimizing the compound shot peening process parameters for optimizing the residual stress on the tooth surface of spiral bevel gears. Background Art

[0002] In a mechanical transmission system, as one of the important transmission components, the performance of spiral bevel gears directly affects the efficiency and service life of the entire system. The tooth surface of spiral bevel gears is subjected to a complex load environment during operation, which causes problems such as wear, fatigue and thermal influence on its surface, thus weakening the service life and reliability of the gears. As a surface treatment technology, the traditional shot peening process is widely used to improve the tooth surface performance. However, due to the diversity of shot peening parameters and their complex influence on the tooth surface stress distribution, it is often difficult to achieve the optimal residual stress distribution and surface strengthening effect.

[0003] Laser shock processing peening (LSP) and shot peening (SP) are important surface strengthening technologies for improving the fatigue life of components. Their action mechanisms are similar, both causing equivalent plastic strain on the target surface and inducing residual compressive stress in its surface and depth directions. Since the residual compressive stress cancels out the tensile stress applied by the outside world, it helps to prevent crack propagation, thereby improving its surface performance. However, there are also differences in their action forms and effects.

[0004] Traditional processes usually rely on experience or simple trial-and-error methods for parameter selection. This method is not only time-consuming and laborious, but also difficult to adapt to changes in different tooth surface geometries, material properties and surface qualities. At the same time, there is still a lack of a systematic method in the prior art for effectively determining the actual application parameters of the shot peening process.

[0005] In addition, in practical applications, the influence of shot peening environmental conditions (such as temperature and humidity) on the shot peening effect has gradually received attention. High-temperature and high-humidity environments may change the dynamic response characteristics of materials, thereby affecting the formation and distribution of residual stress. Due to the dynamic changes in environmental conditions, the stability and consistency of the shot peening process face challenges. Therefore, how to effectively integrate the geometric, material, surface properties and environmental factors of the gears and adjust the shot peening parameters in real time has become an urgent technical problem to be solved.

[0006] In the prior art, the publication number CN112084600A discloses a method for optimizing shot peening process parameters of spiral bevel gears under heavy load and complex working conditions, including: (1) Research on the digital characterization method of the load characteristics of spiral bevel gears under heavy load and complex working conditions; (2) Evaluation of the fatigue performance of spiral bevel gears under heavy load and complex working conditions; (3) Distribution law of shot peening residual stress and roughness distribution of spiral bevel gears based on material constitutive model tests; (4) Optimization of the shot peening process parameters of gears based on the influence law of shot peening process parameters on the stress field distribution state of the tooth surface and subsurface and the fatigue life of the tooth. This method can analyze the digital characterization method of the load characteristics of spiral bevel gears under heavy load and complex working conditions; at the same time, through the material constitutive model and finite element simulation analysis, the influence law of shot peening process parameters on the stress field distribution state of the tooth surface and subsurface and the fatigue life of the tooth is obtained, which is of great significance for the optimization of the shot peening process parameters of gears. However, the influence of external factors on the shot peening process parameters is not considered in the scheme, that is, how to optimize the shot peening process parameters to achieve the best effect is not considered. Therefore, the accuracy and effectiveness of the shot peening process are reduced.

[0007] The above information disclosed in the background art section is only used to enhance the understanding of the background of the present disclosure, and thus it may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0008] The purpose of the present invention is to provide a method, system and storage medium for optimizing the compound shot peening process parameters of the residual stress on the tooth surface of spiral bevel gears to solve the problems raised in the above background art.

[0009] To achieve the above purpose, the present invention provides the following technical solutions:

[0010] A method for optimizing the compound shot peening process parameters of the residual stress on the tooth surface of spiral bevel gears, the specific steps include:

[0011] Obtain the tooth surface geometric parameters, material mechanical property parameters and surface quality parameters of the target spiral bevel gear tooth surface. The tooth surface geometric parameters include tooth height, normal module and helix angle. The material mechanical property parameters include elastic modulus, Poisson's ratio and yield strength. The surface quality parameters include tooth surface average roughness and surface hardness;

[0012] Based on the obtained tooth surface geometric parameters, material mechanical property parameters and surface quality parameters of the target spiral bevel gear tooth surface, calculate the surface strengthening demand coefficient, strengthening uniformity coefficient and surface impact energy coefficient, and respectively correct the core parameters of the compound shot peening according to the calculated surface strengthening demand coefficient, strengthening uniformity coefficient and surface impact energy coefficient to obtain the accurate values of the core parameters of the compound shot peening. The core parameters of the compound shot peening include shot peening pressure, shot peening speed and shot peening coverage rate;

[0013] During the acquisition of environmental parameters of the target spiral bevel gear tooth surface in the composite shot peening process, based on the obtained environmental parameters of the target spiral bevel gear tooth surface, combined with the tooth surface geometric parameters, material mechanical property parameters and surface quality parameters of the target spiral bevel gear tooth surface, a thermal environment enhancement factor is calculated, wherein the environmental parameters of the target spiral bevel gear tooth surface include the temperature of the target spiral bevel gear tooth surface and the environmental humidity;

[0014] Based on the obtained thermal environment enhancement factor, the impact laser power is dynamically corrected to obtain the accurate value of the impact laser power. According to the obtained accurate value of the impact laser power and the accurate value of the core parameters of the composite shot peening, the composite shot peening is carried out to complete the parameter optimization of the composite shot peening process.

[0015] Furthermore, a finite element analysis is carried out on the tooth surface of the target spiral bevel gear to be shot peened to obtain the surface quality parameters. The specific method for obtaining the surface average roughness is as follows:

[0016] The surface roughness measuring device selects a stylus profilometer. Randomly select multiple sampling areas from the surface of the target spiral bevel gear, and use the stylus profilometer to measure and analyze the sampling areas to obtain the surface roughness of each sampling area, and calculate the average value of the surface roughness of all sampling areas. Take this average value as the average roughness of the target spiral bevel gear tooth surface. The calculation formula is as follows:

[0017]

[0018]

[0019] In the formula, L k represents the sampling length of the stylus profilometer in the kth sampling area, k is the index of the sampling area, and k ∈ [1, K], where K is the number of sampling areas, D(x) k is the height of the sampling point at the xth position in the sampling length of the kth sampling area deviating from the center line, x is the coordinate of the sampling point in the sampling length, Ra k is the surface roughness of the kth sampling area, Ra is the average roughness of the target spiral bevel gear tooth surface, and the center line and D(x) k are obtained through data processing by the built-in software of the stylus profilometer;

[0020] Among them, the surface hardness is obtained by correcting the initial surface hardness value based on the environmental temperature and the material yield strength. The specific formula is as follows:

[0021]

[0022] In the formula, H v is the surface hardness of the target spiral bevel gear, H baseis the initial surface hardness value, σ y is the yield strength of the target spiral bevel gear material, T K and T 0 represent the ambient temperature and the reference temperature, respectively.

[0023] Furthermore, based on the obtained tooth surface geometric parameters, material mechanical property parameters, and surface quality parameters of the target spiral bevel gear tooth surface, the surface strengthening demand coefficient, strengthening uniformity coefficient, and surface impact energy coefficient are calculated. The formula for calculating the surface strengthening demand coefficient is as follows:

[0024]

[0025] In the formula, SFI is the surface strengthening demand coefficient, h is the tooth height of the target spiral bevel gear, and β is the spiral angle of the target spiral bevel gear;

[0026] The formula for calculating the strengthening uniformity coefficient is as follows:

[0027]

[0028] In the formula, UC is the strengthening uniformity coefficient, m n represents the normal module of the target spiral bevel gear;

[0029] The formula for calculating the surface impact energy coefficient is as follows:

[0030]

[0031] In the formula, IEF is the surface impact energy coefficient, E is the elastic modulus of the target spiral bevel gear, v is the Poisson's ratio of the target spiral bevel gear, and β 0 is the reference spiral angle.

[0032] Furthermore, according to the calculated surface strengthening demand coefficient, strengthening uniformity coefficient, and surface impact energy coefficient, the core parameters of compound shot peening are corrected respectively to obtain the accurate values of the core parameters of compound shot peening. The formula for calculating the accurate value of the shot peening pressure is as follows:

[0033]

[0034] In the formula, P S is the accurate value of the shot peening pressure, and P 0 is the initial shot peening pressure;

[0035] The formula for calculating the accurate value of the shot peening speed is as follows:

[0036]

[0037] In the formula, V S is the accurate value of the shot peening speed, and V0 is the initial shot peening speed;

[0038] The formula based on which the accurate value of the shot peening coverage rate is calculated is:

[0039] C S = C 0 *SFI 2 *e UC

[0040] In the formula, C S is the accurate value of the shot peening coverage rate, and C 0 is the initial shot peening coverage rate.

[0041] Furthermore, based on the obtained environmental parameters of the target spiral bevel gear tooth surface, combined with the tooth surface geometric parameters, material mechanical property parameters, and surface quality parameters of the target spiral bevel gear tooth surface, a thermal environment enhancement factor is calculated. The formula based on which the thermal environment enhancement factor is calculated is:

[0042]

[0043] In the formula, HEF(t) is the thermal environment enhancement factor at time t, HR(t) is the environmental humidity at time t, T(t) is the temperature of the target spiral bevel gear tooth surface at time t, and the time variable t is the time during the shot peening process.

[0044] Furthermore, based on the obtained thermal environment enhancement factor, the impact laser power is dynamically corrected to obtain the accurate value of the impact laser power. The formula based on which the accurate value of the impact laser power is calculated is:

[0045]

[0046] In the formula, CP(t) is the accurate value of the impact laser power at time t, and CP(t 0 ) is the initial value of the impact laser power at time t 0 , and the time variable t 0 is the initial time when shot peening starts.

[0047] The present invention also provides a composite shot peening process parameter optimization system for optimizing the residual stress of a spiral bevel gear tooth surface. The composite shot peening process parameter optimization system for optimizing the residual stress of a spiral bevel gear tooth surface is used to execute the above-mentioned composite shot peening process parameter optimization method for optimizing the residual stress of a spiral bevel gear tooth surface, and includes:

[0048] A feature parameter acquisition module is used to acquire the tooth surface geometric parameters, material mechanical property parameters, and surface quality parameters of the target spiral bevel gear tooth surface. The tooth surface geometric parameters include tooth height, normal module, and helix angle. The material mechanical property parameters include elastic modulus, Poisson's ratio, and yield strength. The surface quality parameters include the average surface roughness and surface hardness;

[0049] A core parameter optimization module is used to calculate the surface strengthening demand coefficient, strengthening uniformity coefficient, and surface impact energy coefficient based on the tooth surface geometric parameters, material mechanical property parameters, and surface quality parameters of the target spiral bevel gear tooth surface. The core parameters of compound shot peening are corrected respectively according to the calculated surface strengthening demand coefficient, strengthening uniformity coefficient, and surface impact energy coefficient to obtain the accurate values of the core parameters of compound shot peening. The core parameters of compound shot peening include shot peening pressure, shot peening speed, and shot peening coverage;

[0050] An environmental parameter analysis module is used to collect the environmental parameters of the target spiral bevel gear tooth surface during the compound shot peening process. According to the obtained environmental parameters of the target spiral bevel gear tooth surface, combined with the tooth surface geometric parameters, material mechanical property parameters, and surface quality parameters of the target spiral bevel gear tooth surface, the thermal environment enhancement factor is calculated. The environmental parameters of the target spiral bevel gear tooth surface include the temperature of the target spiral bevel gear tooth surface and environmental humidity;

[0051] A laser power optimization module is used to dynamically correct the impact laser power based on the obtained thermal environment enhancement factor to obtain the accurate value of the impact laser power. The compound shot peening is carried out according to the obtained accurate value of the impact laser power and the accurate value of the core parameters of compound shot peening, and the parameter optimization of the compound shot peening process is completed.

[0052] The present invention also provides a storage medium for optimizing the compound shot peening process parameters for residual stress on the spiral bevel gear tooth surface, on which a computer program is stored. When the program is executed by a processor, it realizes the method for optimizing the compound shot peening process parameters for residual stress on the spiral bevel gear tooth surface as described above.

[0053] Compared with the prior art, the beneficial effects of the present invention are:

[0054] First, precisely analyze and obtain the geometric parameters, material mechanical property parameters, and surface quality parameters of the spiral bevel gear tooth surface, laying a solid data foundation for the parameter optimization of the shot peening process. Through these parameters, the tooth surface strengthening requirement coefficient, strengthening uniformity coefficient, and surface impact energy coefficient can be calculated, thereby achieving precise correction of the core parameters of compound shot peening. This method solves the uncertainties and inefficiencies brought about by traditional methods relying on experience and trial-and-error, improving the pertinence and effectiveness of the shot peening process. Additionally, this solution considers the influence of environmental parameters (such as temperature and humidity) during the shot peening process and calculates the thermal environment enhancement factor. It can not only dynamically correct the impact laser power to ensure the stability and consistency of the shot peening process under different environmental conditions but also fill the gap in the existing technology regarding the lack of adaptability to dynamic environments. By combining the thermal environment enhancement factor with the core parameters of shot peening, dynamic adjustment of the shot peening process is achieved, ensuring the optimal distribution of tooth surface residual stress. This not only improves the strengthening effect and fatigue life of the spiral bevel gear tooth surface but also significantly enhances the efficiency and applicability of the shot peening process. At the same time, it has significant practical value and economic benefits in terms of improving gear performance, extending service life, and reducing manufacturing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 is a schematic diagram of the overall method flow of the present invention;

[0056] Figure 2 is a schematic diagram of the overall system structure of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0057] To make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with specific embodiments.

[0058] It should be noted that unless otherwise defined, the technical terms or scientific terms used in the present invention should have the ordinary meanings understood by those of ordinary skill in the field to which the present invention pertains. The "first", "second", and similar terms used in the present invention do not denote any order, quantity, or importance, but are only used to distinguish different components. The terms "including" or "comprising" and the like mean that the elements or items appearing before this word cover the elements or items listed after this word and their equivalents, without excluding other elements or items. The terms "connected" or "coupled" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms "upper", "lower", "left", "right", etc. are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0059] Embodiment:

[0060] Please refer toFigure 1 , the present invention provides a technical solution:

[0061] A method for optimizing the process parameters of compound shot peening for residual stress on the tooth surface of spiral bevel gears, the specific steps include:

[0062] Step 1: Obtain the tooth surface geometric parameters, material mechanical property parameters and surface quality parameters of the target spiral bevel gear tooth surface. The tooth surface geometric parameters include tooth height, normal module and helix angle. The material mechanical property parameters include elastic modulus, Poisson's ratio and yield strength. The surface quality parameters include the average tooth surface roughness and surface hardness.

[0063] Among them, the method for obtaining the tooth surface geometric parameters of the target spiral bevel gear tooth surface includes: Drawings and technical data: Consult the design drawings of the gear or product technical data, which usually have detailed geometric parameter markings, or use precision measuring tools such as vernier calipers and coordinate measuring machines (CMM) to directly measure.

[0064] The methods for obtaining the elastic modulus and Poisson's ratio include: Material specifications and databases: Consult the technical specifications of the material (such as ASTM, GB / T, etc.) or material databases (such as MatWeb), which usually list the elastic modulus and Poisson's ratio of the material; or conduct material tests (such as tensile tests) to directly measure these parameters.

[0065] The method for obtaining the yield strength: Usually, it can be found in the material handbook, or the yield strength can be obtained through standard material tensile tests, carried out in accordance with relevant standards (such as ASTM E8).

[0066] Perform finite element analysis on the tooth surface of the target spiral bevel gear to be shot peened to obtain the surface quality parameters. The specific method for obtaining the surface average roughness is:

[0067] Select a contact profilometer as the surface roughness measurement device. Randomly select multiple sampling areas from the surface of the target spiral bevel gear. Use the contact profilometer to measure and analyze the sampling areas to obtain the surface roughness of each sampling area, and calculate the average value of the surface roughness of all sampling areas. Take this average value as the average tooth surface roughness of the target spiral bevel gear. The calculation formula is as follows:

[0068]

[0069] In the formula, L k represents the sampling length of the contact profilometer in the kth sampling area, k is the index of the sampling area, and k ∈ [1, K], K is the number of sampling areas, D(x) k is the height of the sampling point at the xth position in the sampling length of the kth sampling area deviating from the center line, x is the coordinate of the sampling point in the sampling length, Ra kis the surface roughness of the k-th sampling area, Ra is the average surface roughness of the target spiral bevel gear tooth surface, the center line and D(x) k obtained through data processing by the built-in software of the stylus profilometer;

[0070] where the surface hardness is obtained by correcting the initial surface hardness value based on the ambient temperature and the material yield strength. The specific formula is:

[0071]

[0072] In the formula, H v is the surface hardness of the target spiral bevel gear, H base is the initial surface hardness value, σ y is the yield strength of the spiral bevel gear material, T K and T 0 represent the ambient temperature and the reference temperature respectively.

[0073] Among them, the surface hardness H of the target spiral bevel gear v combines the yield strength of the spiral bevel gear material and the ambient temperature, is used to correct the initial surface hardness value, and represents a more realistic surface hardness value.

[0074] Among them, the yield strength σ of the spiral bevel gear material y its role is to reflect the influence of the mechanical properties (anti-deformation ability) of the material on the surface hardness. Materials with higher yield strength have stronger anti-plastic deformation ability. Therefore, usually the surface hardness is higher. So the yield strength σ of the spiral bevel gear material y is proportional to the surface hardness H of the target spiral bevel gear v The form of taking the square root is to reconcile the non-linear influence of the yield strength on the hardness and ensure that this influence will not be overly amplified.

[0075] An increase in temperature will cause the rigidity of the material to decrease, and at the same time, the internal molecular movement intensifies, and the anti-plastic deformation ability of the material decreases. Therefore, the surface hardness decreases with the increase in temperature. Therefore, the surface hardness H of the target spiral bevel gear v is inversely proportional to the ambient temperature T K The form of with the denominator indicating an inverse relationship reflects the non-linear weakening effect of temperature increase on hardness. In the low-temperature range, the influence of temperature on hardness is small, and in the high-temperature range, the hardness decreases more significantly.

[0076] Among them, the initial surface hardness value H baseIt can be obtained through hardness test experiments in a laboratory environment. Specifically, common hardness test methods include Vickers hardness test, Rockwell hardness test, and Brinell hardness test. Selecting the appropriate method depends on material properties and the required hardness range. The test steps include: ensuring the cleanliness and flatness of the gear tooth surface; calibrating the hardness tester to ensure measurement accuracy; performing hardness measurements according to the standard operating procedure, and recording the average value of multiple points to improve data reliability. Or refer to the product technical documentation provided by the manufacturer, which usually provides hardness specifications.

[0077] Reference temperature T 0 Generally 25 °C.

[0078] Step 2: Based on the tooth surface geometric parameters, material mechanical property parameters, and surface quality parameters of the target spiral bevel gear tooth surface, calculate the surface strengthening demand coefficient, strengthening uniformity coefficient, and surface impact energy coefficient. According to the calculated surface strengthening demand coefficient, strengthening uniformity coefficient, and surface impact energy coefficient, respectively correct the core parameters of compound shot peening to obtain the accurate values of the core parameters of compound shot peening. The core parameters of compound shot peening include shot peening pressure, shot peening speed, and shot peening coverage.

[0079] Based on the tooth surface geometric parameters, material mechanical property parameters, and surface quality parameters of the target spiral bevel gear tooth surface, calculate the surface strengthening demand coefficient, strengthening uniformity coefficient, and surface impact energy coefficient. The formula for calculating the surface strengthening demand coefficient is:

[0080]

[0081] In the formula, SFI is the surface strengthening demand coefficient, h is the tooth height of the target spiral bevel gear, and β is the spiral angle of the target spiral bevel gear;

[0082] Among them, the surface strengthening demand coefficient SFI comprehensively reflects the requirements of tooth surface roughness, tooth height, and material yield strength for the distribution of surface residual stress. The larger the value of the surface strengthening demand coefficient SFI, the greater the strength and the more complex the structure of the target spiral bevel gear, indicating that the tooth surface requires higher shot peening pressure and higher coverage to meet the strengthening requirements.

[0083] Among them, for the average surface roughness Ra of the target spiral bevel gear tooth surface, the higher the tooth surface roughness, the more likely there are defects such as microcracks and machining marks on the surface, resulting in stress concentration. By applying a higher impact energy through the shot peening process, the influence of roughness on fatigue performance can be reduced and the surface compressive stress can be increased. Therefore, the average surface roughness Ra of the target spiral bevel gear tooth surface is proportional to the surface strengthening demand coefficient SFI.

[0084] The greater the tooth height, the deeper the shot peening particles need to penetrate to cover the entire tooth surface and form a sufficient hardened layer below the surface layer. Therefore, a greater pressure is required to meet the strengthening requirements. Thus, the tooth height h of the target spiral bevel gear is proportional to the surface strengthening demand coefficient SFI.

[0085] The higher the yield strength of the material, the stronger its ability to resist plastic deformation. High yield strength materials (such as high-strength steel, titanium alloy, etc.) inherently have strong anti-fatigue and anti-crack properties. High yield strength materials are not prone to large-scale plastic deformation during shot peening. Therefore, the incremental effect of surface strengthening is relatively small. Excessive shot peening pressure may cause surface damage (such as microcracks, spalling, etc.), and even induce reverse effects (such as the surface being too hard while the inner layer is loose, resulting in stress concentration). Therefore, for high yield strength materials, the shot peening pressure can be appropriately reduced. Thus, σ y is inversely proportional to the surface strengthening demand coefficient SFI. Through it will make the influence of the yield strength show a non-linear decreasing trend. That is, as the yield strength increases, its influence on the shot peening demand becomes less significant.

[0086] The spiral angle β of the target spiral bevel gear. The larger the spiral angle of the gear, the higher the geometric complexity of the gear. A complex shape requires a higher shot peening pressure and coverage rate to ensure that the strengthening effect meets the requirements. Thus, the spiral angle β of the target spiral bevel gear is proportional to the surface strengthening demand coefficient SFI.

[0087] The formula based on which the strengthening uniformity coefficient is calculated is as follows:

[0088]

[0089] In the formula, UC is the strengthening uniformity coefficient, m n represents the normal module of the target spiral bevel gear;

[0090] Among them, the strengthening uniformity coefficient UC reflects the complex geometric characteristics of the spiral bevel gear tooth surface and the demand for dynamic strengthening uniformity. The larger the value of the strengthening uniformity coefficient UC, the higher the geometric complexity of the tooth surface, and a higher shot peening speed and coverage rate are required to ensure strengthening uniformity.

[0091] Among them, the normal module m of the target spiral bevel gear n is related to the tooth pitch of the gear. The larger the module, the larger the size of the gear. Therefore, the requirement for the surface strengthening uniformity is higher. The tooth height h of the target spiral bevel gear affects the contact area and force distribution of the gear. A higher gear may require greater uniformity to adapt to uniform contact. Therefore, the tooth height h of the target spiral bevel gear and the normal module m of the target spiral bevel gear n are both proportional to the strengthening uniformity coefficient UC. Using The form balances the influence between the modulus and the tooth height and avoids the excessive influence of the direct linear growth of geometric parameters on the results.

[0092] The helix angle β of the target spiral bevel gear. The larger the helix angle of the gear, the higher the geometric complexity of the gear. A complex shape requires a higher shot peening pressure and coverage rate to ensure that the strengthening effect meets the requirements. Therefore, the helix angle β of the target spiral bevel gear is directly proportional to the strengthening uniformity coefficient UC, through e -|sinβ| It represents an inverse relationship in the form of the denominator.

[0093] The formula for calculating the surface impact energy coefficient is as follows:

[0094]

[0095] In the formula, IEF is the surface impact energy coefficient, E is the elastic modulus of the target spiral bevel gear, v is the Poisson's ratio of the target spiral bevel gear, β 0 is the reference helix angle.

[0096] The higher the surface hardness, the stronger the ability of the material surface layer to resist compression and plastic deformation. To introduce residual compressive stress or change the surface state on a high-hardness surface, a higher shot peening impact kinetic energy (higher shot peening speed) is required. Therefore, H v is directly proportional to the surface impact energy coefficient IEF.

[0097] The elastic modulus reflects the rigidity of the material, that is, the ability of the material to resist deformation in the elastic deformation stage. The higher the elastic modulus, the more rigid the material, and it is more difficult for the surface to be hit by shot peening particles and undergo plastic deformation. Therefore, the elastic modulus E appears in the denominator, indicating that the higher the rigidity, the smaller the required impact kinetic energy, because the material itself already has good anti-deformation ability. Therefore, the surface impact energy coefficient is inversely proportional to the elastic modulus E.

[0098] The larger the Poisson's ratio v of the target spiral bevel gear, the stronger the lateral deformation ability of the material (closer to rubber-like materials), and the kinetic energy of shot peening impact is easily dispersed and cannot effectively act on the tooth surface strengthening; the smaller the Poisson's ratio v of the target spiral bevel gear, the weaker the lateral deformation ability of the material (closer to metal-like materials), and the shot peening impact energy is more concentrated on the surface, thus affecting the strengthening effect. Therefore, the Poisson's ratio v of the target spiral bevel gear is directly proportional to the surface impact energy coefficient IEF. Through the square root represents a direct proportional relationship.

[0099] The influence of the helix angle on the surface impact energy coefficient IEF is the same as above and will not be elaborated here. The reference helix angle β 0 can be set according to the actual situation combined with expert experience, generally between 45 and 90 degrees.

[0100] The core parameters of compound shot peening are corrected according to the calculated surface strengthening demand coefficient, strengthening uniformity coefficient, and surface impact energy coefficient to obtain the accurate values of the core parameters of compound shot peening. The formula for calculating the accurate value of shot peening pressure is as follows:

[0101]

[0102] In the formula, P S is the accurate value of shot peening pressure, and P 0 is the initial shot peening pressure;

[0103] Since the positive correlation between IEF and SFI and shot peening pressure has been described above, it will not be elaborated here. At the same time, the proportional relationship is represented in the form of e -SFI in the denominator, which is used to indicate that when the surface strengthening demand coefficient SFI is larger, the strengthening demand is higher, and the shot peening pressure should be increased to meet the strengthening demand.

[0104] The formula for calculating the accurate value of shot peening speed is as follows:

[0105]

[0106] In the formula, V S is the accurate value of shot peening speed, V 0 is the initial shot peening speed. The square root is used to indicate that when the surface impact energy coefficient IEF is large enough, it has a significant impact on the accurate value of shot peening speed V S , and when it is small, the impact on the accurate value of shot peening speed V S is small;

[0107] The logarithmic function ln(1 + UC) is used to indicate that as the strengthening uniformity coefficient UC increases, the impact on the accurate value of shot peening speed V S gradually decreases.

[0108] The formula for calculating the accurate value of shot peening coverage is as follows:

[0109] C S = C 0 * SFI 2 * e UC

[0110] In the formula, C S is the accurate value of shot peening coverage, and C 0 is the initial shot peening coverage.

[0111] The calculation formulas for the accurate value of shot peening speed V S and the accurate value of shot peening coverage C S are the same as those for the accurate value of shot peening pressure and will not be elaborated here. Among them, through the square of SFI 2The form represents the significant influence of the surface strengthening demand coefficient SFI on the exact value of the shot peening coverage rate, through the exponential function e UC represents the positive correlation between the strengthening uniformity coefficient UC and the exact value C of the shot peening coverage rate S The greater the strengthening uniformity coefficient UC, the more uniform the shot peening, that is, a greater coverage rate is required.

[0112] Step 3: Collect the environmental parameters of the target spiral bevel gear tooth surface during the compound shot peening process. According to the obtained environmental parameters of the target spiral bevel gear tooth surface, combined with the tooth surface geometric parameters, material mechanical property parameters, and surface quality parameters of the target spiral bevel gear tooth surface, calculate the thermal environment enhancement factor, where the environmental parameters of the target spiral bevel gear tooth surface include the temperature of the target spiral bevel gear tooth surface and the environmental humidity.

[0113] According to the obtained environmental parameters of the target spiral bevel gear tooth surface, combined with the tooth surface geometric parameters, material mechanical property parameters, and surface quality parameters of the target spiral bevel gear tooth surface, calculate the thermal environment enhancement factor, where the formula for calculating the thermal environment enhancement factor is:

[0114]

[0115] In the formula, HEF(t) is the thermal environment enhancement factor at time t, HR(t) is the environmental humidity at time t, T(t) is the temperature of the target spiral bevel gear tooth surface at time t, and the time t is the time variable during the shot peening process.

[0116] Among them, the thermal environment enhancement factor HEF(t) at time t comprehensively considers the environmental humidity, tooth surface temperature, etc., and is used to characterize the influence of different times on the impact laser power. The larger the value of the thermal environment enhancement factor HEF(t) at time t, the higher the tooth surface complexity and the harsher the environmental conditions, and a higher laser power is required. The impact laser power should be increased to meet the strength requirements.

[0117] Among them, Ra is a key parameter for the machining quality of the gear tooth surface, which affects the energy absorption efficiency of the laser power. The larger Ra is, the greater the laser power required to meet the energy absorption efficiency. Therefore, Ra is proportional to the thermal environment enhancement factor HEF(t) at time t.

[0118] When the humidity increases, the number of water molecules and aerosol particles in the air increases. These particles can scatter the laser, causing the laser to attenuate during transmission. To ensure that the laser energy reaches the expected intensity at the target, it is necessary to increase the output power of the laser to compensate for the loss caused by scattering. Therefore, the environmental humidity HR(t) at time t is proportional to the thermal environment enhancement factor HEF(t) at time t.

[0119] Among them, the larger the target spiral bevel gear tooth surface temperature T(t) at time t, the more unstable the target spiral bevel gear tooth surface is, which may lead to a decrease in the mechanical properties of the gear material, including a decrease in hardness and weakening of strength. The material may be more susceptible to plastic deformation at high temperatures, affecting the bearing capacity of the gear. Continuous high temperatures may cause thermal fatigue and cracking of the tooth surface, increasing the risk of gear failure. Therefore, the impact laser power should be reduced to reduce the temperature and avoid the risk of damage to the gear structure. Therefore, the target spiral bevel gear tooth surface temperature T(t) at time t is inversely proportional to the thermal environment enhancement factor HEF(t) at time t.

[0120] Step 4: Based on the obtained thermal environment enhancement factor, the shock laser power is dynamically corrected to obtain the precise value of the shock laser power. Composite shot peening is performed according to the obtained precise value of the shock laser power and the precise value of the composite shot peening core parameters to complete the parameter optimization of the composite shot peening process.

[0121] Based on the obtained thermal environment enhancement factor, the shock laser power is dynamically corrected to obtain the precise value of the shock laser power. The formula for calculating the precise value of the shock laser power is:

[0122]

[0123] Where CP(t) is the precise value of the impact laser power at time t, CP(t 0 ) is t 0 The initial value of the impact laser power at time t 0 The time is the initial time when shot peening starts.

[0124] Since the above is to illustrate the proportional relationship between the precise value of the impact laser power and the thermal environment enhancement factor HEF(t) at time t, we will not repeat it here. It means that with the increase of thermal environment enhancement factor HEF(t), the influence on the precise value of shock laser power gradually decreases.

[0125] See also Figure 2 The present invention also provides a composite shot peening process parameter optimization system for optimizing the residual stress on the tooth surface of a spiral bevel gear. The composite shot peening process parameter optimization system for optimizing the residual stress on the tooth surface of a spiral bevel gear is used to execute the composite shot peening process parameter optimization method for optimizing the residual stress on the tooth surface of a spiral bevel gear, comprising:

[0126] A characteristic parameter acquisition module, used to acquire tooth surface geometric parameters, material mechanical property parameters and surface quality parameters of the target spiral bevel gear tooth surface, wherein the tooth surface geometric parameters include tooth height, normal module and helix angle, the material mechanical property parameters include elastic modulus, Poisson's ratio and yield strength, and the surface quality parameters include tooth surface average roughness and surface hardness;

[0127] The core parameter optimization module is used to calculate the surface strengthening demand coefficient, strengthening uniformity coefficient, and surface impact energy coefficient based on the tooth surface geometric parameters, material mechanical property parameters, and surface quality parameters of the target spiral bevel gear tooth surface, and correct the core parameters of compound shot peening respectively according to the calculated surface strengthening demand coefficient, strengthening uniformity coefficient, and surface impact energy coefficient to obtain the accurate values of the core parameters of compound shot peening. The core parameters of compound shot peening include shot peening pressure, shot peening speed, and shot peening coverage rate;

[0128] The environmental parameter analysis module is used to collect the environmental parameters of the target spiral bevel gear tooth surface during the compound shot peening process, and calculate the thermal environment enhancement factor according to the obtained environmental parameters of the target spiral bevel gear tooth surface in combination with the tooth surface geometric parameters, material mechanical property parameters, and surface quality parameters of the target spiral bevel gear tooth surface. The environmental parameters of the target spiral bevel gear tooth surface include the temperature of the target spiral bevel gear tooth surface and environmental humidity;

[0129] The laser power optimization module is used to dynamically correct the impact laser power based on the obtained thermal environment enhancement factor to obtain the accurate value of the impact laser power, and perform compound shot peening according to the obtained accurate value of the impact laser power and the accurate value of the core parameters of compound shot peening to complete the parameter optimization of the compound shot peening process.

[0130] The present invention also provides a storage medium for optimizing the process parameters of compound shot peening for residual stress on the tooth surface of spiral bevel gears, on which a computer program is stored. When the program is executed by a processor, it realizes the method for optimizing the process parameters of compound shot peening for residual stress on the tooth surface of spiral bevel gears as described above.

[0131] The above formulas are all dimensionless and take their numerical values for calculation. The formulas are obtained by collecting a large amount of data for software simulation to get a formula closest to the actual situation. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0132] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. Those skilled in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software methods depends on the specific application and design constraints of the technical solution.

[0133] The unit described as a separation component may or may not be physically separated. The component shown as a unit may or may not be a physical unit, and it may be located in one place or distributed across multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0134] As described above, the above are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should all be covered within the protection scope of the present application.

Claims

1. A composite shot peening process parameter optimization method for optimizing the residual stress on the tooth surface of spiral bevel gears, characterized in that: The specific steps include: Acquire tooth surface geometric parameters, material mechanical property parameters and surface quality parameters of the target spiral bevel gear tooth surface, wherein the tooth surface geometric parameters include tooth height, normal module and helix angle, the material mechanical property parameters include elastic modulus, Poisson's ratio and yield strength, and the surface quality parameters include tooth surface average roughness and surface hardness; Based on the tooth surface geometric parameters, material mechanical property parameters and surface quality parameters of the target spiral bevel gear tooth surface, the surface strengthening requirement coefficient, the strengthening uniformity coefficient and the surface impact energy coefficient are calculated, and the composite shot peening core parameters are respectively corrected according to the calculated surface strengthening requirement coefficient, strengthening uniformity coefficient and surface impact energy coefficient to obtain the precise values ​​of the composite shot peening core parameters, which include shot peening pressure, shot peening speed and shot peening coverage; Collect environmental parameters of the target spiral bevel gear tooth surface during the composite shot peening process, and calculate the thermal environment enhancement factor according to the obtained environmental parameters of the target spiral bevel gear tooth surface, combined with the tooth surface geometric parameters, material mechanical property parameters and surface quality parameters of the target spiral bevel gear tooth surface, wherein the environmental parameters of the target spiral bevel gear tooth surface include the target spiral bevel gear tooth surface temperature and environmental humidity; Based on the obtained thermal environment enhancement factor, the shock laser power is dynamically corrected to obtain the precise value of the shock laser power. Composite shot peening is performed according to the obtained precise value of the shock laser power and the precise value of the core parameters of composite shot peening to complete the parameter optimization of the composite shot peening process.

2. The composite shot peening process parameter optimization method for optimizing the residual stress on the tooth surface of spiral bevel gears according to claim 1, characterized in that: Obtain surface quality parameters, the specific method for obtaining the surface average roughness is: The surface roughness measurement equipment uses a stylus profilometer. Multiple sampling areas are randomly selected from the surface of the target spiral bevel gear. The stylus profilometer is used to measure and analyze the sampling areas to obtain the surface roughness of each sampling area, and the surface roughness average of all sampling areas is calculated. This average is used as the average roughness of the target spiral bevel gear tooth surface. The calculation formula is as follows: Where, L k represents the sampling length of the stylus profilometer in the kth sampling area, k is the index of the sampling area, and k∈[1,K], K is the number of sampling areas, D(x) k is the height of the x-th sampling point within the sampling length of the k-th sampling area from the center line, x is the coordinate of the sampling point within the sampling length, Ra k is the surface roughness of the kth sampling area, Ra is the average roughness of the target spiral bevel gear tooth surface, the center line and D(x) k The data is obtained by processing the built-in software of the stylus profilometer; The surface hardness is obtained by correcting the initial surface hardness value based on the ambient temperature and the material yield strength. The specific formula is: In the formula, H v is the surface hardness of the target spiral bevel gear, H base is the initial surface hardness value, σ y is the yield strength of the target spiral bevel gear material, T K and T0 represent the ambient temperature and reference temperature respectively.

3. The composite shot peening process parameter optimization method for optimizing the residual stress on the tooth surface of spiral bevel gears according to claim 2, characterized in that: Based on the tooth surface geometric parameters, material mechanical properties parameters and surface quality parameters of the target spiral bevel gear tooth surface, the surface strengthening requirement coefficient, strengthening uniformity coefficient and surface impact energy coefficient are calculated. The formula for calculating the surface strengthening requirement coefficient is: Where SFI is the surface strengthening requirement coefficient, h is the tooth height of the target spiral bevel gear, and β is the helix angle of the target spiral bevel gear; The formula for calculating the enhancement uniformity coefficient is: Where UC is the uniformity coefficient, m n represents the normal module of the target spiral bevel gear; The surface impact energy coefficient is calculated based on the formula: Where IEF is the surface impact energy coefficient, E is the elastic modulus of the target spiral bevel gear, v is the Poisson's ratio of the target spiral bevel gear, and β0 is the reference helix angle.

4. The composite shot peening process parameter optimization method for optimizing the residual stress on the tooth surface of spiral bevel gears according to claim 3, characterized in that: According to the calculated surface strengthening demand coefficient, strengthening uniformity coefficient and surface impact energy coefficient, the composite shot peening core parameters are corrected respectively to obtain the precise values ​​of the composite shot peening core parameters. The formula for calculating the precise value of the shot peening pressure is: Where P S is the precise value of shot peening pressure, P0 is the initial shot peening pressure; The formula for calculating the precise value of shot peening speed is: Where V S is the precise value of shot peening speed, V0 is the initial shot peening speed; The formula for calculating the precise value of shot peening coverage is: C S =C0*SFI 2 *e UC In the formula, C S is the exact value of shot peening coverage, and C0 is the initial shot peening coverage.

5. The composite shot peening process parameter optimization method for optimizing the residual stress on the tooth surface of spiral bevel gears according to claim 3, characterized in that: According to the obtained environmental parameters of the target spiral bevel gear tooth surface, combined with the tooth surface geometric parameters, material mechanical properties parameters and surface quality parameters of the target spiral bevel gear tooth surface, the thermal environment enhancement factor is calculated, wherein the formula for calculating the thermal environment enhancement factor is: Where HEF(t) is the thermal environment enhancement factor at time t, HR(t) is the ambient humidity at time t, T(t) is the target spiral bevel gear tooth surface temperature at time t, and time t is the time variable in the shot peening process.

6. The composite shot peening process parameter optimization method for optimizing the residual stress on the tooth surface of spiral bevel gears according to claim 5, characterized in that: Based on the obtained thermal environment enhancement factor, the shock laser power is dynamically corrected to obtain the precise value of the shock laser power. The formula for calculating the precise value of the shock laser power is: Wherein, CP(t) is the precise value of the impact laser power at time t, CP(t0) is the initial value of the impact laser power at time t0, and the time t0 is the initial time for starting shot peening.

7. A composite shot peening process parameter optimization system for optimizing residual stress on spiral bevel gear tooth surface, characterized in that: The composite shot peening process parameter optimization system for optimizing the residual stress on the tooth surface of a spiral bevel gear is used to execute the composite shot peening process parameter optimization method for optimizing the residual stress on the tooth surface of a spiral bevel gear according to any one of claims 1 to 6, comprising: A characteristic parameter acquisition module, used to acquire tooth surface geometric parameters, material mechanical property parameters and surface quality parameters of the target spiral bevel gear tooth surface, wherein the tooth surface geometric parameters include tooth height, normal module and helix angle, the material mechanical property parameters include elastic modulus, Poisson's ratio and yield strength, and the surface quality parameters include tooth surface average roughness and surface hardness; A core parameter optimization module is used to calculate the surface strengthening requirement coefficient, the strengthening uniformity coefficient and the surface impact energy coefficient based on the tooth surface geometric parameters, material mechanical property parameters and surface quality parameters of the target spiral bevel gear tooth surface, and to correct the composite shot peening core parameters according to the calculated surface strengthening requirement coefficient, strengthening uniformity coefficient and surface impact energy coefficient, respectively, to obtain the precise values ​​of the composite shot peening core parameters, wherein the composite shot peening core parameters include shot peening pressure, shot peening speed and shot peening coverage; An environmental parameter analysis module is used to collect environmental parameters of the target spiral bevel gear tooth surface during the composite shot peening process, and calculate the thermal environment enhancement factor based on the obtained environmental parameters of the target spiral bevel gear tooth surface, combined with the tooth surface geometric parameters, material mechanical property parameters and surface quality parameters of the target spiral bevel gear tooth surface, wherein the environmental parameters of the target spiral bevel gear tooth surface include the target spiral bevel gear tooth surface temperature and environmental humidity; The laser power optimization module is used to dynamically correct the impact laser power based on the obtained thermal environment enhancement factor to obtain the precise value of the impact laser power, perform composite shot peening according to the obtained precise value of the impact laser power and the precise value of the composite shot peening core parameters, and complete the parameter optimization of the composite shot peening process.

8. A composite shot peening process parameter optimization storage medium for optimizing residual stress on the tooth surface of a spiral bevel gear, having a computer program stored thereon, characterized in that: When the program is executed by a processor, the composite shot peening process parameter optimization method for optimizing the residual stress on the tooth surface of a spiral bevel gear as described in any one of claims 1 to 6 is implemented.

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