A method for optimizing a ceramic ball regrinding process and an industrial application system

Abstract

The application discloses a ceramic ball regrinding process optimization method and an industrial application system, and the method comprises the following steps: setting an annealing temperature according to the material type of a ceramic ball blank to obtain a pretreated ceramic ball; performing first-stage coarse grinding under a first grinding pressure to obtain a first coarse-ground ceramic ball; adding the first coarse-ground ceramic ball, second grinding material and grinding fluid into a coarse grinding device, performing second-stage coarse grinding under a second grinding pressure to obtain a second coarse-ground ceramic ball; transferring the second coarse-ground ceramic ball into an ultrasonic-assisted fine grinding device, performing fine grinding on the second coarse-ground ceramic ball by using fine grinding material under ultrasonic vibration, and controlling the processing temperature in the fine grinding process to obtain a fine-ground ceramic ball; and placing the fine-ground ceramic ball into a chemical mechanical polishing device, performing polishing on the fine-ground ceramic ball by using a nanoscale chemical mechanical polishing fluid to obtain a regrinded ceramic ball; and the application reduces the micro-protrusions on the surface of the ceramic ball by the combined action of chemical action and mechanical micro-removal, so that the surface roughness and the spherical surface quality of the regrinded ceramic ball are improved.

Description

Technical Field

[0001] This invention relates to the field of precision ceramic processing and manufacturing technology, and in particular to an optimization method for ceramic ball regrinding process and its industrial application system. Background Technology

[0002] Ceramic balls possess characteristics such as high hardness, good wear resistance, strong corrosion resistance, and low density, making them suitable for precision transmission applications in high-end CNC machine tool electric spindle bearings, aerospace engine bearings, and moving parts of semiconductor equipment. These applications place high demands on the ceramic balls' diameter consistency, roundness, sphericity, surface roughness, and subsurface integrity. After sintering, hot isostatic pressing, or initial machining of the ceramic ball blank, a regrinding process is typically required to further improve geometric accuracy and surface quality.

[0003] Current ceramic ball regrinding processes typically employ a combination of coarse grinding, fine grinding, and polishing. In the coarse grinding stage, higher grinding pressures are often used to improve material removal efficiency; in the fine grinding stage, surface quality is improved by reducing the abrasive particle size. Because ceramic materials are typically hard and brittle, when fine abrasive particles act on the ceramic ball surface under high pressure, localized indentation, brittle spalling, and subsurface microcracks can easily form. Simultaneously, residual tensile stress or a modified surface layer may remain on the ceramic ball surface. These microcracks and residual tensile stress are not easily detected by conventional visual inspection but can affect the fatigue life and operational reliability of the ceramic ball under high-speed, high-load conditions.

[0004] Therefore, there is a need to provide a process method that can coordinate annealing, abrasive particle size reduction, grinding pressure reduction, ultrasonic-assisted fine grinding, temperature control and chemical mechanical polishing during the regrinding of ceramic balls, so as to achieve a matching relationship between ceramic balls in terms of size trimming, surface quality improvement and subsurface damage suppression. Summary of the Invention

[0005] This invention provides an optimization method and industrial application system for ceramic ball regrinding process, which solves the problems of subsurface microcrack deepening, unstable residual stress state and insufficient surface integrity caused by the mismatch between abrasive particle size variation and grinding pressure control in the existing ceramic ball regrinding process.

[0006] In a first aspect, the present invention discloses an optimization method for the regrinding process of ceramic balls, comprising the following steps: S1. Set the annealing temperature according to the material type of the ceramic ball blank, and perform annealing treatment on the ceramic ball blank to obtain pretreated ceramic balls; S2. Add the pretreated ceramic balls, the first abrasive and the grinding fluid into the coarse grinding equipment, and perform the first stage of coarse grinding under the first grinding pressure to obtain the first coarse-ground ceramic balls. S3. Discharge the residual abrasive and grinding fluid after the first stage of coarse grinding. After cleaning the first coarse grinding ceramic ball, add the first coarse grinding ceramic ball, the second abrasive and grinding fluid into the coarse grinding equipment and perform the second stage of coarse grinding under the second grinding pressure to obtain the second coarse grinding ceramic ball. Wherein, the particle size of the second abrasive is smaller than that of the first abrasive, and the second grinding pressure is lower than that of the first grinding pressure, so that the decreasing relationship of abrasive particle size corresponds to the decreasing relationship of grinding pressure; S4. Transfer the second coarsely ground ceramic ball into an ultrasonic-assisted fine grinding device, and perform fine grinding with fine grinding abrasive under ultrasonic vibration environment, while controlling the processing temperature during the fine grinding process to obtain finely ground ceramic balls. S5. Place the finely ground ceramic ball into a chemical mechanical polishing device and polish it with a nano-level chemical mechanical polishing liquid to obtain a refurbished ceramic ball.

[0007] Further, S1, S2, and S3 include the following parameter settings: when the ceramic ball blank is a zirconia ceramic ball blank, the annealing temperature is 600-800℃; when the ceramic ball blank is a silicon nitride ceramic ball blank, the annealing temperature is 850-950℃; the particle size of the first abrasive is W28-W40, and the first grinding pressure is 0.4-0.6MPa; the particle size of the second abrasive is W10-W20, and the second grinding pressure is 0.2-0.4MPa; both the first abrasive and the second abrasive are diamond micro powder.

[0008] In some embodiments, S2 includes the following steps: S2-1. Mix the first abrasive with the grinding fluid to form a first abrasive suspension; S2-2, Add the pretreated ceramic balls and the first abrasive suspension to a coarse grinding device with a grinding tank; S2-3. Apply the first grinding pressure to the pretreated ceramic ball and drive the grinding disc to rotate, so that the pretreated ceramic ball rolls and grinds in the grinding tank. S2-4. During the first-stage coarse grinding process, monitor the temperature of the grinding zone, and stop the first-stage coarse grinding after the pretreated ceramic balls reach the first preset removal amount, the first preset roundness, or the first preset processing time, to obtain the first coarse-ground ceramic balls.

[0009] In some embodiments, S3 includes the following steps: S3-1. Discharge the residual abrasive, grinding fluid and grinding debris after the first stage of coarse grinding, and clean the first coarse grinding ceramic balls; S3-2. Mix the second abrasive with the grinding fluid to form a second abrasive suspension; S3-3. Add the cleaned first coarse grinding ceramic balls and the second abrasive suspension to the coarse grinding equipment; S3-4. Apply the second grinding pressure to the first coarse grinding ceramic ball and drive the grinding disc to rotate, so that the first coarse grinding ceramic ball continues to roll and grind under conditions lower than the first level of coarse grinding pressure; S3-5. After the first coarse grinding ceramic ball reaches the second preset removal amount, the second preset roundness, or the second preset processing time, stop the second stage of coarse grinding to obtain the second coarse grinding ceramic ball.

[0010] In some embodiments, S4 includes the following steps: S4-1. Add the second coarse grinding ceramic ball into the fine grinding disc of the ultrasonic-assisted fine grinding equipment; S4-2. Mix the fine grinding abrasive with the fine grinding liquid to form a fine grinding abrasive suspension, and supply the fine grinding abrasive suspension to the fine grinding disc; S4-3. Apply ultrasonic vibration to the grinding disc, grinding fluid, or grinding disc support structure through an ultrasonic transducer and an amplitude transformer. S4-4. Set the ultrasonic frequency according to the material type of the ceramic ball blank; S4-5. The second coarse-ground ceramic ball is fine-ground under ultrasonic vibration environment, and the processing temperature is controlled to 20±1℃ by the cooling circulation component to obtain the fine-ground ceramic ball. The abrasive used for fine grinding is boron carbide micro powder or diamond micro powder, and the particle size of the abrasive is W3.5-W7. When the ceramic ball blank is a zirconia ceramic ball blank, the ultrasonic frequency is 20-28kHz; when the ceramic ball blank is a silicon nitride ceramic ball blank, the ultrasonic frequency is 35-40kHz.

[0011] In some embodiments, the ultrasonic-assisted fine grinding device is a planetary gear set rotary fine grinding machine, and S4 further includes: arranging the second coarse grinding ceramic ball between the grinding discs of the planetary gear set rotary fine grinding machine; controlling the sun gear, gear ring, and cage to rotate respectively, so that the second coarse grinding ceramic ball forms a multi-directional rolling trajectory in the fine grinding disc; wherein, the sun gear speed is 100-120 rpm, the gear ring speed is 80-100 rpm, and the cage rotation speed is 30-50 rpm.

[0012] In some embodiments, S4 further includes an online monitoring and adjustment step: S4-A1. During ultrasonic-assisted fine grinding, grinding force signals are collected in real time by a grinding force sensor. S4-A2: Calculate the average grinding force based on the grinding force signal within the preset time window, and determine the grinding force fluctuation range based on the current grinding force and the average grinding force; S4-A3. Compare the grinding force fluctuation amplitude with a preset fluctuation threshold; S4-A4 When the fluctuation of the grinding force exceeds 15% of the average grinding force, reduce at least one of the loading pressure, grinding disc speed or feed speed, and increase the coolant flow rate.

[0013] In some embodiments, S5 includes the following steps: S5-1. Select nano-sized silica polishing liquid or nano-sized cerium dioxide polishing liquid as the nano-sized chemical mechanical polishing liquid according to the material type of the ceramic ball blank. S5-2. Adjust the pH value of the nanoscale chemical mechanical polishing slurry to 9.5-10.5, and add 0.1%-1% of oxidant to the nanoscale chemical mechanical polishing slurry; S5-3. Place the finely ground ceramic ball between the polishing pad and the polishing disc, and perform chemical mechanical polishing under a polishing pressure of 0.05-0.15 MPa; S5-4. After polishing, the ceramic balls are cleaned and dried to obtain the refurbished ceramic balls.

[0014] This invention provides an optimized method for the regrinding process of ceramic balls, which has the following beneficial effects: This invention establishes a correspondence between the decreasing abrasive particle size and the decreasing grinding pressure during the coarse grinding stage. This allows the larger abrasive particles to complete the initial material removal under higher grinding pressure, while the smaller abrasive particles continue surface finishing under lower grinding pressure. This avoids excessive indentation of fine abrasive particles into the ceramic ball surface under high pressure, reducing the risk of further propagation of subsurface microcracks.

[0015] The present invention includes a step for discharging and cleaning residual abrasive, grinding fluid and grinding debris between the first-stage coarse grinding and the second-stage coarse grinding. This can reduce the amount of coarse abrasive residue entering the second-stage coarse grinding process, prevent abnormal scratches caused by coarse abrasive in the low-particle-size grinding stage, and make the graded coarse grinding process more stable.

[0016] This invention sets the annealing temperature and ultrasonic frequency according to the material type of the ceramic ball blank, so that the zirconia ceramic ball blank and the silicon nitride ceramic ball blank can be processed under suitable heat treatment conditions and ultrasonic-assisted fine grinding conditions, thereby reducing processing damage caused by material differences.

[0017] This invention controls the processing temperature during ultrasonic-assisted fine grinding and addresses abnormal grinding conditions through grinding force monitoring and adjustment. When the grinding force fluctuation exceeds 15% of the average grinding force, the impact of local overload and heat accumulation on the surface integrity of the ceramic ball can be reduced by decreasing at least one of the loading pressure, grinding disc rotation speed, or feed rate, and increasing the coolant flow rate.

[0018] This invention employs a nanoscale chemical mechanical polishing slurry for chemical mechanical polishing after ultrasonic-assisted fine grinding. Through the combined effects of chemical action and mechanical micro-removal, the micro-protrusions on the surface of the ceramic ball are reduced, thereby improving the surface roughness and spherical quality of the refurbished ceramic ball.

[0019] In a first aspect, the present invention discloses that it also provides an industrial application system for regrinding ceramic balls, comprising: The annealing module is used to set the annealing temperature according to the material type of the ceramic ball blank, and to anneal the ceramic ball blank to obtain pretreated ceramic balls. The graded coarse grinding module is used to add the pretreated ceramic balls, the first abrasive and the grinding fluid into the coarse grinding equipment, and perform the first stage of coarse grinding under the first grinding pressure to obtain the first coarse grinding ceramic balls. After discharging the residual abrasive and grinding fluid after the first stage of coarse grinding and cleaning the first coarse grinding ceramic balls, the first coarse grinding ceramic balls, the second abrasive and the grinding fluid are added into the coarse grinding equipment, and the second stage of coarse grinding is performed under the second grinding pressure to obtain the second coarse grinding ceramic balls. Wherein, the particle size of the second abrasive is smaller than that of the first abrasive, and the second grinding pressure is lower than that of the first grinding pressure, so that the decreasing relationship of abrasive particle size corresponds to the decreasing relationship of grinding pressure; The ultrasonic-assisted fine grinding module is used to transfer the second coarse-grinding ceramic ball into the ultrasonic-assisted fine grinding equipment, and to finely grind it using fine grinding abrasive in an ultrasonic vibration environment to obtain finely ground ceramic balls. Temperature control module, used to control the processing temperature during fine grinding; A chemical mechanical polishing module is used to place the finely ground ceramic balls into a chemical mechanical polishing device and polish them with a nano-scale chemical mechanical polishing liquid to obtain refurbished ceramic balls.

[0020] Further, the graded coarse grinding module includes a first coarse grinding unit, a cleaning unit, and a second coarse grinding unit; the first coarse grinding unit is used to add the pretreated ceramic balls, the first abrasive, and the grinding fluid into the coarse grinding equipment, and drive the pretreated ceramic balls to roll and grind under a first grinding pressure; the cleaning unit is used to discharge the residual abrasive, grinding fluid, and grinding debris after the first coarse grinding, and to clean the first coarse grinding ceramic balls; the second coarse grinding unit is used to add the cleaned first coarse grinding ceramic balls, the second abrasive, and the grinding fluid into the coarse grinding equipment, and drive the first coarse grinding ceramic balls to roll and grind under a second grinding pressure; the ceramic ball regrinding industrial application system also includes a grinding force monitoring module and a control module; the grinding force monitoring module is used to collect grinding force signals in real time during ultrasonic-assisted fine grinding; the control module is used to determine the grinding force fluctuation amplitude based on the average grinding force within a preset time window, and when the grinding force fluctuation amplitude exceeds 15% of the average grinding force, control the ultrasonic-assisted fine grinding module to reduce at least one of the loading pressure, grinding disc speed, or feed speed, and control the temperature control module to increase the coolant flow rate. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the process optimization method for regrinding ceramic balls according to the present invention.

[0022] Figure 2 This is a schematic diagram of the preparation process of the first coarsely ground ceramic ball of the present invention; Figure 3 This is a schematic diagram of the preparation process of the second coarse-ground ceramic of the present invention; Figure 4 This is a structural block diagram of the ceramic ball regrinding industrial application system of the present invention. Detailed Implementation

[0023] The technical solution of the present invention will be described below with reference to specific embodiments. The following embodiments are used to illustrate the technical solution of the present invention. In actual implementation, the specific parameters can be adaptively adjusted according to the ceramic ball material, ball diameter specifications, target accuracy level and production equipment conditions.

[0024] The optimized regrinding process method for ceramic balls of the present invention can be used for regrinding hard and brittle ceramic balls such as zirconia ceramic balls and silicon nitride ceramic balls. This method releases residual stress inside the blank through annealing, aligns the decreasing abrasive particle size with the decreasing grinding pressure through staged coarse grinding, improves the fine grinding state through ultrasonic-assisted fine grinding and temperature control, and further enhances the surface quality of the ceramic balls through chemical mechanical polishing.

[0025] Reference Figures 1 to 4 The present invention implements the optimization method and industrial application system of ceramic ball regrinding process through the following embodiments. Example

[0026] This embodiment uses a zirconia ceramic ball blank as an example to illustrate the optimization method of the ceramic ball regrinding process of the present invention.

[0027] S1. Set the annealing temperature according to the material type of the ceramic ball blank, and perform annealing treatment on the ceramic ball blank to obtain pretreated ceramic balls.

[0028] Specifically, sintered zirconia ceramic sphere blanks are selected. Before processing, the zirconia ceramic sphere blanks can be ultrasonically cleaned in a cleaning solution to remove surface dust, binder residues, and sintered deposits. After cleaning, the zirconia ceramic sphere blanks are dried and then placed in an annealing furnace for annealing.

[0029] In this embodiment, the annealing temperature of the zirconia ceramic ball blank is 750℃, and the holding time is 3 hours. After the holding time, the blank is cooled by furnace cooling to obtain pretreated ceramic balls. Annealing can reduce the residual thermal stress inside the zirconia ceramic ball blank caused by uneven sintering and cooling, making it less likely for stress concentration to occur during subsequent rough grinding.

[0030] S2. The pretreated ceramic balls, the first abrasive, and the grinding fluid are added to the coarse grinding equipment, and the first stage of coarse grinding is carried out under the first grinding pressure to obtain the first coarse-ground ceramic balls.

[0031] Specifically, the first abrasive is mixed with grinding fluid to form a first abrasive suspension. The first abrasive can be diamond micron powder with a particle size of W28-W40. In this embodiment, the first abrasive is W40 diamond micron powder.

[0032] Pretreated ceramic balls and a first abrasive suspension are added to a coarse grinding device with a grinding tank. The coarse grinding device can be a grinding mill with a V-groove grinding disc. A first grinding pressure is applied to the pretreated ceramic balls, and the grinding disc is driven to rotate, causing the pretreated ceramic balls to roll and grind within the grinding tank. In this embodiment, the first grinding pressure is 0.55 MPa.

[0033] During the first-stage rough grinding process, the temperature of the grinding zone can be monitored using a temperature sensor or an infrared thermometer. Once the pretreated ceramic balls reach the first preset removal amount, the first preset roundness, or the first preset processing time, the first-stage rough grinding is stopped, resulting in the first-stage rough-ground ceramic balls. The first preset removal amount, the first preset roundness, and the first preset processing time can be set based on the initial dimensional deviation and target dimensional accuracy of the ceramic ball blank.

[0034] S3. Discharge the residual abrasive and grinding fluid after the first stage of coarse grinding. After cleaning the first coarse grinding ceramic ball, add the first coarse grinding ceramic ball, the second abrasive and grinding fluid into the coarse grinding equipment and perform the second stage of coarse grinding under the second grinding pressure to obtain the second coarse grinding ceramic ball.

[0035] Specifically, after the first stage of coarse grinding, the residual abrasive, grinding fluid, and grinding debris from the first stage are discharged, and the ceramic balls from the first stage of coarse grinding are cleaned. Cleaning can be done using deionized water, ultrasonic cleaning, or a combination of both, to reduce the amount of residual abrasive from the first stage entering the second stage of coarse grinding.

[0036] Subsequently, the second abrasive is mixed with the grinding fluid to form a second abrasive suspension. The particle size of the second abrasive is smaller than that of the first abrasive. In this embodiment, the second abrasive is W20 diamond micro powder.

[0037] The cleaned first coarse grinding ceramic balls and the second abrasive suspension are added to the coarse grinding equipment. A second grinding pressure is applied to the first coarse grinding ceramic balls, and the grinding disc is driven to rotate, so that the first coarse grinding ceramic balls continue to roll and grind under a pressure lower than that of the first stage of coarse grinding. In this embodiment, the second grinding pressure is 0.25 MPa.

[0038] As a result, the abrasive particle size was reduced from W40 to W20, and the grinding pressure was reduced from 0.55 MPa to 0.25 MPa, making the decreasing relationship between abrasive particle size and decreasing relationship between grinding pressure correspond. This correspondence can reduce the local indentation of fine abrasive particles on the surface of ceramic balls under high pressure, making the second-stage coarse grinding more suitable for surface finishing.

[0039] When the first coarse grinding ceramic ball reaches the second preset removal amount, the second preset roundness, or the second preset processing time, the second stage of coarse grinding is stopped, and the second coarse grinding ceramic ball is obtained.

[0040] S4. Transfer the second coarse-ground ceramic ball into an ultrasonic-assisted fine grinding device, and perform fine grinding with fine grinding abrasive under ultrasonic vibration environment, while controlling the processing temperature during the fine grinding process to obtain fine-ground ceramic balls.

[0041] Specifically, the second coarse grinding ceramic ball is added to the fine grinding disc of the ultrasonic-assisted fine grinding equipment. The fine grinding abrasive is mixed with the fine grinding fluid to form a fine grinding abrasive suspension, and the fine grinding abrasive suspension is supplied to the fine grinding disc. In this embodiment, the fine grinding abrasive is W7 boron carbide micro powder.

[0042] Ultrasonic vibration is applied to the grinding disc, grinding fluid, or grinding disc support structure via an ultrasonic transducer and amplitude transformer. For zirconia ceramic sphere blanks, the ultrasonic frequency can be set to 20-28 kHz. In this embodiment, the ultrasonic frequency is 28 kHz.

[0043] The second coarse grinding ceramic ball is finely ground under ultrasonic vibration, and the processing temperature is controlled at 20±1℃ by a cooling circulation assembly. The cooling circulation assembly may include a coolant pump, a heat exchanger, a temperature sensor, and circulation pipelines. The temperature sensor detects the temperature of the fine grinding fluid or the fine grinding zone, and the coolant pump adjusts the coolant flow rate according to the temperature detection result.

[0044] In one embodiment, the ultrasonic-assisted fine grinding equipment is a planetary gear rotary fine grinding machine. Second coarse grinding ceramic balls are arranged between the grinding discs of the planetary gear rotary fine grinding machine. The sun gear, ring gear, and cage are controlled to rotate respectively, causing the second coarse grinding ceramic balls to form a multi-directional rolling trajectory within the fine grinding discs. Specifically, the sun gear rotates at 100-120 rpm, the ring gear rotates at 80-100 rpm, and the cage rotates at 30-50 rpm.

[0045] S5. Place the finely ground ceramic ball into a chemical mechanical polishing device and polish it with a nano-level chemical mechanical polishing liquid to obtain a refurbished ceramic ball.

[0046] Specifically, nano-sized silica polishing slurry or nano-sized cerium dioxide polishing slurry is selected as the nano-sized chemical mechanical polishing slurry according to the material type of the ceramic ball blank. In this embodiment, nano-sized silica polishing slurry is used. The pH value of the nano-sized chemical mechanical polishing slurry is adjusted to 9.8, and 0.5% oxidant is added to the nano-sized chemical mechanical polishing slurry.

[0047] The finely ground ceramic balls are placed between a polishing pad and a polishing disc, and chemical mechanical polishing is performed under a polishing pressure of 0.05-0.15 MPa. In this embodiment, the polishing pressure is 0.1 MPa. After polishing, the ceramic balls are cleaned and dried to obtain refractory ceramic balls. Example

[0048] This embodiment uses silicon nitride ceramic ball blanks as an example to illustrate the optimization method of ceramic ball regrinding process of the present invention.

[0049] S1. Set the annealing temperature according to the material type of the ceramic ball blank, and perform annealing treatment on the ceramic ball blank to obtain pretreated ceramic balls.

[0050] Specifically, silicon nitride ceramic ball blanks that have undergone hot isostatic pressing are selected. After cleaning and drying, the silicon nitride ceramic ball blanks are placed in an annealing furnace for annealing. In this embodiment, the annealing temperature of the silicon nitride ceramic ball blanks is 900℃, and the holding time is 4 hours. After annealing, pretreated ceramic balls are obtained.

[0051] S2. The pretreated ceramic balls, the first abrasive, and the grinding fluid are added to the coarse grinding equipment, and the first stage of coarse grinding is carried out under the first grinding pressure to obtain the first coarse-ground ceramic balls.

[0052] In this embodiment, the first abrasive is W32 diamond micro powder, and the first grinding pressure is 0.6 MPa. The first abrasive is mixed with grinding fluid and added to the coarse grinding equipment, and the pre-treated ceramic balls are rolled and ground in the grinding tank. When the first preset removal amount, first preset roundness, or first preset processing time is reached, the first stage of coarse grinding is stopped, resulting in the first coarsely ground ceramic balls.

[0053] S3. Discharge the residual abrasive and grinding fluid after the first stage of coarse grinding. After cleaning the first coarse grinding ceramic ball, add the first coarse grinding ceramic ball, the second abrasive and grinding fluid into the coarse grinding equipment and perform the second stage of coarse grinding under the second grinding pressure to obtain the second coarse grinding ceramic ball.

[0054] In this embodiment, the second abrasive is W14 diamond micro powder, and the second grinding pressure is 0.3 MPa. The particle size of the second abrasive is smaller than that of the first abrasive, and the second grinding pressure is lower than that of the first grinding pressure, so that the decreasing relationship of the abrasive particle size corresponds to the decreasing relationship of the grinding pressure.

[0055] Because silicon nitride ceramic balls have high hardness, if the high grinding pressure of the first stage is maintained during the second stage of coarse grinding, fine abrasive particles can easily form localized indentations on the surface of the ceramic balls. Therefore, in this embodiment, while reducing the abrasive particle size from W32 to W14, the grinding pressure is reduced from 0.6 MPa to 0.3 MPa, making the second stage of coarse grinding more suitable for surface finishing.

[0056] S4. Transfer the second coarse-ground ceramic ball into an ultrasonic-assisted fine grinding device, and perform fine grinding with fine grinding abrasive under ultrasonic vibration environment, while controlling the processing temperature during the fine grinding process to obtain fine-ground ceramic balls.

[0057] In this embodiment, W5 boron carbide micro powder is used as the abrasive for fine grinding. For the silicon nitride ceramic ball blank, the ultrasonic frequency can be set to 35-40 kHz. In this embodiment, the ultrasonic frequency is 35 kHz. During the fine grinding process, the processing temperature is controlled at 20 ± 1℃ through a cooling circulation assembly.

[0058] S5. Place the finely ground ceramic ball into a chemical mechanical polishing device and polish it with a nano-level chemical mechanical polishing liquid to obtain a refurbished ceramic ball.

[0059] In this embodiment, nano-sized cerium dioxide polishing slurry is used as the nano-sized chemical mechanical polishing slurry. The pH value of the nano-sized cerium dioxide polishing slurry is adjusted to 10.0, and 0.5% oxidant is added. The finely ground ceramic balls are placed between the polishing pad and the polishing disc for chemical mechanical polishing. After polishing, they are cleaned and dried to obtain refurbished ceramic balls. Example

[0060] This embodiment illustrates the online monitoring and adjustment steps during the ultrasonic-assisted fine grinding process.

[0061] A grinding force sensor is installed on the ultrasonic-assisted fine grinding equipment. The grinding force sensor can be installed at the grinding disc loading mechanism, spindle support structure, or fine grinding disc mounting base to collect grinding force signals in real time during the ultrasonic-assisted fine grinding process.

[0062] The control module calculates the average grinding force based on the grinding force signal within a preset time window, and determines the grinding force fluctuation amplitude based on the current grinding force and the average grinding force. Let the current grinding force be F, and the average grinding force within the preset time window be Favg, then the grinding force fluctuation amplitude can be expressed as: ; in, This indicates the fluctuation range of the grinding force, where F represents the current grinding force. This represents the average grinding force within a preset time window.

[0063] The control module compares the grinding force fluctuation amplitude with a preset fluctuation threshold. When the grinding force fluctuation amplitude exceeds 15% of the average grinding force, the control module reduces at least one of the following: loading pressure, grinding disc speed, or feed rate, and increases coolant flow rate.

[0064] Through the above online monitoring and adjustment steps, local overload, abrasive accumulation, insufficient cooling, or abnormal movement of ceramic balls can be adjusted during ultrasonic-assisted fine grinding, thereby reducing the impact of abnormal grinding conditions on the surface of ceramic balls. Example

[0065] This embodiment illustrates an industrial application system for regrinding ceramic balls.

[0066] The industrial application system for regrinding ceramic balls includes an annealing module, a graded coarse grinding module, an ultrasonic-assisted fine grinding module, a temperature control module, and a chemical mechanical polishing module.

[0067] The annealing module is used to set the annealing temperature according to the material type of the ceramic ball blank and to anneal the ceramic ball blank to obtain pretreated ceramic balls. The annealing module may include an annealing furnace, a temperature sensor, and a temperature controller. When the ceramic ball blank is a zirconia ceramic ball blank, the annealing temperature can be set to 600-800℃; when the ceramic ball blank is a silicon nitride ceramic ball blank, the annealing temperature can be set to 850-950℃.

[0068] The graded coarse grinding module is used to add pretreated ceramic balls, first abrasive and grinding fluid into the coarse grinding equipment, and perform first-stage coarse grinding under the first grinding pressure to obtain first coarse-ground ceramic balls. After discharging the residual abrasive and grinding fluid after the first-stage coarse grinding and cleaning the first coarse-ground ceramic balls, the first coarse-ground ceramic balls, second abrasive and grinding fluid are added into the coarse grinding equipment, and the second-stage coarse grinding is performed under the second grinding pressure to obtain second coarse-ground ceramic balls.

[0069] In this process, the particle size of the second abrasive is smaller than that of the first abrasive, and the second grinding pressure is lower than that of the first grinding pressure, so that the decreasing relationship of the abrasive particle size corresponds to the decreasing relationship of the grinding pressure. The graded coarse grinding module may include a first coarse grinding unit, a cleaning unit, and a second coarse grinding unit. The first coarse grinding unit is used to add pretreated ceramic balls, a first abrasive, and grinding fluid to the coarse grinding equipment, and drive the pretreated ceramic balls to roll and grind under a first grinding pressure. The cleaning unit is used to discharge residual abrasive, grinding fluid, and grinding debris after the first stage of coarse grinding, and to clean the first coarse grinding ceramic balls. The second coarse grinding unit is used to add the cleaned first coarse grinding ceramic balls, a second abrasive, and grinding fluid to the coarse grinding equipment, and drive the first coarse grinding ceramic balls to roll and grind under a second grinding pressure.

[0070] The ultrasonic-assisted fine grinding module is used to transfer the second coarse-ground ceramic balls into the ultrasonic-assisted fine grinding equipment, where they are finely ground using fine grinding abrasives under ultrasonic vibration to obtain finely ground ceramic balls. The ultrasonic-assisted fine grinding module may include a fine grinding disc, an ultrasonic transducer, an amplitude transformer, and a fine grinding fluid supply assembly.

[0071] The temperature control module is used to control the processing temperature during the fine grinding process. The temperature control module may include a temperature sensor, a coolant pump, a heat exchanger, and circulation piping. The temperature sensor detects the temperature of the fine grinding zone or the grinding fluid, and the coolant pump adjusts the coolant flow rate based on the temperature detection results to maintain the processing temperature at 20±1℃.

[0072] The chemical mechanical polishing (CMP) module is used to place finely ground ceramic balls into a CMP device and polish them using a nanoscale CMP slurry to obtain refurbished ceramic balls. The CMP module may include a polishing disc, a polishing pad, a polishing slurry supply assembly, and a cleaning and drying assembly.

[0073] The industrial application system for ceramic ball regrinding may also include a grinding force monitoring module and a control module. The grinding force monitoring module is used to acquire grinding force signals in real time during ultrasonic-assisted fine grinding. The control module is used to determine the grinding force fluctuation amplitude based on the average grinding force within a preset time window, and when the grinding force fluctuation amplitude exceeds 15% of the average grinding force, it controls the ultrasonic-assisted fine grinding module to reduce at least one of the following: loading pressure, grinding disc speed, or feed rate; and it controls the temperature control module to increase the coolant flow rate.

[0074] The above-mentioned ceramic ball regrinding industrial application system can realize continuous or semi-continuous execution of annealing treatment, graded rough grinding, ultrasonic-assisted fine grinding, temperature control, chemical mechanical polishing, and abnormal adjustment of grinding force, thereby improving the consistency and stability of ceramic ball regrinding.

[0075] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An optimization method for the regrinding process of ceramic balls, characterized in that, Includes the following steps: S1. Set the annealing temperature according to the material type of the ceramic ball blank, and perform annealing treatment on the ceramic ball blank to obtain pretreated ceramic balls; S2. Add the pretreated ceramic balls, the first abrasive and the grinding fluid into the coarse grinding equipment, and perform the first stage of coarse grinding under the first grinding pressure to obtain the first coarse-ground ceramic balls. S3. Discharge the residual abrasive and grinding fluid after the first stage of coarse grinding. After cleaning the first coarse grinding ceramic ball, add the first coarse grinding ceramic ball, the second abrasive and grinding fluid into the coarse grinding equipment and perform the second stage of coarse grinding under the second grinding pressure to obtain the second coarse grinding ceramic ball. Wherein, the particle size of the second abrasive is smaller than that of the first abrasive, and the second grinding pressure is lower than that of the first grinding pressure, so that the decreasing relationship of abrasive particle size corresponds to the decreasing relationship of grinding pressure; S4. Transfer the second coarsely ground ceramic ball into an ultrasonic-assisted fine grinding device, and perform fine grinding with fine grinding abrasive under ultrasonic vibration environment, while controlling the processing temperature during the fine grinding process to obtain finely ground ceramic balls. S5. Place the finely ground ceramic ball into a chemical mechanical polishing device and polish it with a nano-level chemical mechanical polishing liquid to obtain a refurbished ceramic ball.

2. The method for optimizing the regrinding process of ceramic balls according to claim 1, characterized in that, The parameters S1, S2, and S3 include the following settings: When the ceramic ball blank is a zirconia ceramic ball blank, the annealing temperature is 600-800℃; When the ceramic ball blank is a silicon nitride ceramic ball blank, the annealing temperature is 850-950℃; The particle size of the first abrasive is W28-W40, and the first grinding pressure is 0.4-0.6 MPa; The particle size of the second abrasive is W10-W20, and the second grinding pressure is 0.2-0.4 MPa; Both the first abrasive and the second abrasive are diamond micro powder.

3. The method for optimizing the regrinding process of ceramic balls according to claim 1, characterized in that, S2 includes the following steps: S2-1. Mix the first abrasive with the grinding fluid to form a first abrasive suspension; S2-2, Add the pretreated ceramic balls and the first abrasive suspension to a coarse grinding device with a grinding tank; S2-3. Apply the first grinding pressure to the pretreated ceramic ball and drive the grinding disc to rotate, so that the pretreated ceramic ball rolls and grinds in the grinding tank. S2-4. During the first-stage coarse grinding process, monitor the temperature of the grinding zone, and stop the first-stage coarse grinding after the pretreated ceramic balls reach the first preset removal amount, the first preset roundness, or the first preset processing time, to obtain the first coarse-ground ceramic balls.

4. The method for optimizing the regrinding process of ceramic balls according to claim 1, characterized in that, S3 includes the following steps: S3-1. Discharge the residual abrasive, grinding fluid and grinding debris after the first stage of coarse grinding, and clean the first coarse grinding ceramic balls; S3-2. Mix the second abrasive with the grinding fluid to form a second abrasive suspension; S3-3. Add the cleaned first coarse grinding ceramic balls and the second abrasive suspension to the coarse grinding equipment; S3-4. Apply the second grinding pressure to the first coarse grinding ceramic ball and drive the grinding disc to rotate, so that the first coarse grinding ceramic ball continues to roll and grind under conditions lower than the first level of coarse grinding pressure; S3-5. After the first coarse grinding ceramic ball reaches the second preset removal amount, the second preset roundness, or the second preset processing time, stop the second stage of coarse grinding to obtain the second coarse grinding ceramic ball.

5. The method for optimizing the regrinding process of ceramic balls according to claim 1, characterized in that, S4 includes the following steps: S4-1. Add the second coarse grinding ceramic ball into the fine grinding disc of the ultrasonic-assisted fine grinding equipment; S4-2. Mix the fine grinding abrasive with the fine grinding liquid to form a fine grinding abrasive suspension, and supply the fine grinding abrasive suspension to the fine grinding disc; S4-3. Apply ultrasonic vibration to the grinding disc, grinding fluid, or grinding disc support structure through an ultrasonic transducer and an amplitude transformer. S4-4. Set the ultrasonic frequency according to the material type of the ceramic ball blank; S4-5. The second coarse-ground ceramic ball is fine-ground under ultrasonic vibration environment, and the processing temperature is controlled to 20±1℃ by the cooling circulation component to obtain the fine-ground ceramic ball. The abrasive used for fine grinding is boron carbide micro powder or diamond micro powder, and the particle size of the abrasive is W3.5-W7. When the ceramic ball blank is a zirconia ceramic ball blank, the ultrasonic frequency is 20-28kHz; when the ceramic ball blank is a silicon nitride ceramic ball blank, the ultrasonic frequency is 35-40kHz.

6. The method for optimizing the regrinding process of ceramic balls according to claim 5, characterized in that, The ultrasonic-assisted fine grinding equipment is a planetary gear set rotary fine grinding machine, and S4 further includes: The second coarse grinding ceramic ball is arranged between the grinding discs of the planetary gear set rotary fine grinding mill; Control the rotation of the sun gear, gear ring, and cage respectively, so that the second coarse grinding ceramic ball forms a multi-directional rolling trajectory in the fine grinding disk; The sun gear rotates at 100-120 rpm, the ring gear rotates at 80-100 rpm, and the cage rotates at 30-50 rpm.

7. The method for optimizing the regrinding process of ceramic balls according to claim 1, characterized in that, S4 also includes an online monitoring and adjustment step: S4-A1. During ultrasonic-assisted fine grinding, grinding force signals are collected in real time by a grinding force sensor. S4-A2: Calculate the average grinding force based on the grinding force signal within the preset time window, and determine the grinding force fluctuation range based on the current grinding force and the average grinding force; S4-A3. Compare the grinding force fluctuation amplitude with a preset fluctuation threshold; S4-A4 When the fluctuation of the grinding force exceeds 15% of the average grinding force, reduce at least one of the loading pressure, grinding disc speed or feed speed, and increase the coolant flow rate.

8. The method for optimizing the regrinding process of ceramic balls according to claim 1, characterized in that, S5 includes the following steps: S5-1. Select nano-sized silica polishing liquid or nano-sized cerium dioxide polishing liquid as the nano-sized chemical mechanical polishing liquid according to the material type of the ceramic ball blank. S5-2. Adjust the pH value of the nanoscale chemical mechanical polishing slurry to 9.5-10.5, and add 0.1%-1% of oxidant to the nanoscale chemical mechanical polishing slurry; S5-3. Place the finely ground ceramic ball between the polishing pad and the polishing disc, and perform chemical mechanical polishing under a polishing pressure of 0.05-0.15 MPa; S5-4. After polishing, the ceramic balls are cleaned and dried to obtain the refurbished ceramic balls.

9. An industrial application system for regrinding ceramic balls, characterized in that, include: The annealing module is used to set the annealing temperature according to the material type of the ceramic ball blank, and to anneal the ceramic ball blank to obtain pretreated ceramic balls. The graded coarse grinding module is used to add the pretreated ceramic balls, the first abrasive and the grinding fluid into the coarse grinding equipment, and perform the first stage of coarse grinding under the first grinding pressure to obtain the first coarse grinding ceramic balls. After discharging the residual abrasive and grinding fluid after the first stage of coarse grinding and cleaning the first coarse grinding ceramic balls, the first coarse grinding ceramic balls, the second abrasive and the grinding fluid are added into the coarse grinding equipment, and the second stage of coarse grinding is performed under the second grinding pressure to obtain the second coarse grinding ceramic balls. Wherein, the particle size of the second abrasive is smaller than that of the first abrasive, and the second grinding pressure is lower than that of the first grinding pressure, so that the decreasing relationship of abrasive particle size corresponds to the decreasing relationship of grinding pressure; The ultrasonic-assisted fine grinding module is used to transfer the second coarse-grinding ceramic ball into the ultrasonic-assisted fine grinding equipment, and to finely grind it using fine grinding abrasive in an ultrasonic vibration environment to obtain finely ground ceramic balls. Temperature control module, used to control the processing temperature during fine grinding; A chemical mechanical polishing module is used to place the finely ground ceramic balls into a chemical mechanical polishing device and polish them with a nano-scale chemical mechanical polishing liquid to obtain refurbished ceramic balls.

10. The ceramic ball regrinding industrial application system according to claim 9, characterized in that, The graded coarse grinding module includes a first coarse grinding unit, a cleaning unit, and a second coarse grinding unit. The first coarse grinding unit is used to add the pretreated ceramic balls, the first abrasive and the grinding fluid into the coarse grinding equipment, and drive the pretreated ceramic balls to roll and grind under the first grinding pressure; The cleaning unit is used to discharge the residual abrasive, grinding fluid and grinding debris after the first stage of coarse grinding, and to clean the first coarse grinding ceramic balls; The second coarse grinding unit is used to add the cleaned first coarse grinding ceramic ball, the second abrasive and the grinding fluid into the coarse grinding equipment, and drive the first coarse grinding ceramic ball to roll and grind under the second grinding pressure; The ceramic ball regrinding industrial application system also includes a grinding force monitoring module and a control module; The grinding force monitoring module is used to collect grinding force signals in real time during ultrasonic-assisted fine grinding. The control module is used to determine the grinding force fluctuation range based on the average grinding force within a preset time window, and when the grinding force fluctuation range exceeds 15% of the average grinding force, it controls the ultrasonic-assisted fine grinding module to reduce at least one of the loading pressure, grinding disc rotation speed or feed speed, and controls the temperature control module to increase the coolant flow rate.

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