Microstructured CBN (Cubic Boron Nitride) grinding wheel for double-arc raceway grinding and preparation method of microstructured CBN grinding wheel

Abstract

The invention relates to the technical field of precision grinding machining, in particular to a microstructured CBN grinding wheel for double-arc raceway grinding and a preparation method thereof.The microstructured CBN grinding wheel comprises an annularly-arranged base body, the base body serves as a foundation of the CBN grinding wheel and is used for being connected with a grinding rod, and an annular ceramic CBN layer is arranged on the outer ring of the base body and used for conducting grinding work; a structured area is arranged on the outer side, away from the base body, of the ceramic CBN layer, and the section shape of the structured area is matched with a target raceway; arc-shaped grinding surfaces are arranged on the two sides of the structured area respectively, and the two arc-shaped grinding surfaces are symmetrically arranged on the two sides of the structured area; and a microstructure array is arranged on the grinding surface. The contact area of the grinding wheel and the surface of the workpiece can be effectively reduced, the grinding force and the grinding temperature are reduced, grinding cracks can be effectively reduced, and therefore the surface quality of the ground workpiece is improved.

Description

Technical Field

[0001] This invention relates to the field of precision grinding technology, and in particular to a microstructured CBN grinding wheel for double circular arc raceway grinding and its preparation method. Background Technology

[0002] Double-arc raceways can better distribute loads evenly and reduce contact stress, resulting in higher load-bearing capacity, higher rigidity, better wear resistance, and longer service life. They are commonly found in high-load, high-precision ball screw assemblies and are widely used in heavy-duty machinery, aerospace, and the automotive industry. As a core component for achieving transmission functions, the grinding quality of the double-arc raceways in ball screw assemblies directly determines the transmission accuracy, transmission efficiency, load-bearing capacity, and service life of electromechanical servo systems.

[0003] Traditional grinding tools such as cubic boron nitride (CBN) grinding wheels generally use profile grinding when performing double arc-shaped raceway grinding. The grinding process generates large grinding forces, the grinding wheel is prone to clogging, the cooling performance is poor, the grinding heat is high, and the residual stress is large, which makes the ground surface prone to micro-cracks, resulting in low grinding accuracy and efficiency, and making it difficult to guarantee the quality of the processed surface.

[0004] Therefore, this application designs a microstructured CBN grinding wheel for double circular arc raceway grinding and its preparation method to solve the above-mentioned technical problems. Summary of the Invention

[0005] The purpose of this invention is to provide a microstructured CBN grinding wheel for double circular arc raceway grinding and its preparation method, aiming to solve the problems of high grinding force, easy clogging of grinding wheel, poor cooling performance, high grinding heat, large residual stress, and easy generation of microcracks on the grinding surface in existing double circular arc raceway grinding processes.

[0006] To achieve the above objectives, the present invention provides the following solution: The present invention provides a microstructured CBN grinding wheel for double circular arc raceway grinding, comprising a ring-shaped substrate, the substrate serving as the base of the CBN grinding wheel for connection with a grinding rod, and the outer ring of the substrate being provided with a ring-shaped ceramic CBN layer for grinding operations;

[0007] The ceramic CBN layer has a structured region on its outer side away from the substrate, and the cross-sectional shape of the structured region is adapted to the target raceway.

[0008] The structured region is provided with arc-shaped grinding surfaces on both sides, and the two arc-shaped grinding surfaces are symmetrically arranged on both sides of the structured region; a microstructure array is provided on the arc-shaped grinding surfaces.

[0009] Preferably, the microstructure array includes a plurality of microgrooves, which are uniformly arrayed along the circumferential direction of the arc-shaped grinding surface, and the microgrooves on the two arc-shaped grinding surfaces are symmetrically arranged.

[0010] Preferably, the width of the microgroove is w, the depth is D, the angle between the microgroove and the radial direction of the CBN grinding wheel is θ, and the spacing between adjacent microgrooves is α, satisfying the following formula:

[0011]

[0012]

[0013]

[0014]

[0015] Where k1, k2, and k3 are proportional coefficients, R0 is the initial dressing allowance, N is the number of dressing cycles for the CBN grinding wheel, Δd is the dressing depth per cycle, and F t For tangential grinding force, σ b d represents the fracture strength of the ceramic CBN layer. g H represents the abrasive grain size. b H represents the hardness of the grinding wheel bond. w The hardness of the workpiece material.

[0016] Preferably, the initial trimming allowance R0 satisfies

[0017]

[0018] Among them, E m For the manufacturing precision of grinding wheels, E i This refers to the installation deviation of the grinding wheel.

[0019] Preferably, the single trimming depth Δd satisfies

[0020]

[0021] Among them, R w Where n is the grinding wheel wear rate, L is the workpiece raceway length, and n is the grinding wheel wear rate. c a is the number of grinding operations within a dressing cycle. p This refers to the grinding depth.

[0022] This invention discloses a method for preparing a microstructured CBN grinding wheel for double-circular-arc raceway grinding, comprising the following steps:

[0023] Step 1. Mount the CBN grinding wheel to be processed on the grinding spindle that can move along the X direction, and mount the dressing wheel on the dressing spindle that can move along the Z direction. Adjust the spatial position of the grinding spindle and the dressing spindle so that their axes are parallel and the center line of the CBN grinding wheel is aligned with that of the dressing wheel.

[0024] Step 2. Based on the arc raceway parameters of the workpiece, obtain the radius R2 and the arc eccentricity a of the arc of the required arc grinding surface. The grinding spindle and the dressing spindle move in conjunction to achieve the initial dressing of the CBN grinding wheel and obtain a CBN grinding wheel without microstructure.

[0025] Step 3. Mount the laser galvanometer on a laser platform that can move along the Z-axis. Adjust the spatial position of the laser platform and the grinding spindle so that the arc surface of the arc-shaped grinding surface is located within the machined area of ​​the laser. When the width H in the Z-direction of the arc structure on one side of the CBN grinding wheel is less than or equal to 2*Z... R At that time, one-time processing; when the width H of the single-sided arc structure of the CBN grinding wheel in the z-direction is greater than 2*Z R At that time, the process is divided into multiple steps;

[0026] Step 4. Use a laser to process microstructures on the arc-shaped grinding surface. Adjust the position of the laser platform so that the arc-shaped grinding surface to be processed is located at the Rayleigh length Z of the laser beam. R Inside, the microstructure array is processed layer by layer until the surface of the arc-shaped grinding surface has a microstructure array, and the processing of the microstructure array on one side is completed.

[0027] Step 5. Turn the CBN grinding wheel over and repeat steps 3 and 4 to complete the preparation of the microstructured CBN grinding wheel.

[0028] Preferably, in step one, the dressing wheel is used to set the tool on the left and right sides of the CBN grinding wheel, and the coordinate positions of the dressing wheel are recorded as a1 and a2 respectively. The dressing wheel is then adjusted to the coordinate position A0 of (a1+a2) / 2 to achieve centerline alignment.

[0029] Preferably, in step two, the dressing spindle is adjusted to coordinate position A1 (a1+a2+a) / 2+R2+r, and the grinding spindle is moved until the CBN grinding wheel contacts the dressing wheel to achieve dressing and tool setting. Then, the grinding spindle and the dressing spindle run in conjunction to run a double arc dressing trajectory to achieve the initial dressing of the CBN grinding wheel.

[0030] Preferably, in step three, when multiple processing operations are performed, the number of processing operations is n:

[0031] .

[0032] Preferably, in step three, laser energy field modeling is performed, and the laser processing trajectory is optimized by varying the spacing. The X-direction displacement is achieved by adjusting the density of the scan lines in the grating scan. The scan density is increased in the low-energy region and decreased in the high-energy region, thereby achieving uniformity of global energy deposition.

[0033] This invention discloses a microstructured CBN grinding wheel for double circular arc raceway grinding and its preparation method. Compared with the prior art, this invention has the following advantages and technical effects:

[0034] 1) The microstructured CBN grinding wheel for double arc raceway grinding disclosed in this invention can effectively reduce the contact area between the grinding wheel and the workpiece surface, reduce the grinding force and grinding temperature, and thus effectively reduce the generation of grinding cracks, thereby improving the grinding quality.

[0035] 2) The microstructured CBN grinding wheel for double arc raceway grinding disclosed in this invention has a microstructure array on its arc-shaped grinding surface that can accommodate grinding chips, effectively reduce grinding wear, improve the chip holding and chip removal capacity of the CBN grinding wheel, and can also accommodate grinding fluid, which is beneficial for the grinding fluid to enter the grinding area, which is beneficial for reducing the grinding temperature of the workpiece, reducing grinding burn, and thus improving the surface finish.

[0036] 3) The method for preparing a microstructured CBN grinding wheel for double-arc raceway grinding disclosed in this invention utilizes picosecond laser processing to cause transient evaporation or thermal oxidation on the surface of the CBN grinding wheel, thereby rapidly removing the material. The method considers the influence of different laser incident angles on the laser processing parameters on the arc of the grinding wheel and optimizes the laser processing trajectory. To ensure the uniformity of the width and depth of the microstructure processed by the arc grinding wheel, the density of the scanning lines in the grating scanning is adjusted. The scanning density is increased in the low-energy area and decreased in the high-energy area, thereby achieving uniformity of global energy deposition and realizing the efficient preparation of a microstructured CBN grinding wheel for double-arc raceway grinding. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0038] Figure 1 This is a schematic diagram of the microstructured CBN grinding wheel used for double circular arc raceway grinding according to the present invention;

[0039] Figure 2This is a schematic diagram of the microstructured CBN grinding wheel structure for double circular arc raceway grinding according to the present invention;

[0040] Figure 3 This is a front view of the microstructured CBN grinding wheel used for double circular arc raceway grinding according to the present invention;

[0041] Figure 4 This is a side view of the microstructured CBN grinding wheel used for double circular arc raceway grinding according to the present invention;

[0042] Figure 5 This is a diagram of the equipment used in the preparation method of the microstructured CBN grinding wheel for double circular arc raceway grinding according to the present invention.

[0043] Figure 6 This is a schematic diagram of laser defocusing processing of the laser of the present invention;

[0044] Figure 7 This is a schematic diagram of the laser distribution of the laser of the present invention on the surface of the arc-shaped grinding surface;

[0045] Figure 8 This is a schematic diagram of the laser optimization trajectory of the laser of the present invention;

[0046] Figure 9 The diagram shows the cumulative laser energy distribution of the laser in this invention before and after laser optimization.

[0047] Figure 10 A comparison of the scanning path spacing before and after laser optimization of the laser of the present invention;

[0048] Figure 11 This is a flowchart illustrating the optimized scanning path in the preparation method of the microstructured CBN grinding wheel for double circular arc raceway grinding according to the present invention.

[0049] In the figure: 1. CBN grinding wheel; 2. Grinding spindle; 3. Dressing wheel; 4. Dressing spindle; 5. Laser; 6. Laser platform; 101. Substrate; 102. Ceramic CBN layer; 103. Arc-shaped grinding surface; 104. Microstructure array; 105. Microgroove. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0052] Reference Figures 1 to 11 As shown, this embodiment provides a microstructured CBN grinding wheel for double circular arc raceway grinding, including a ring-shaped substrate 101, which serves as the base of the CBN grinding wheel 1 and is used to connect with the grinding rod. The outer ring of the substrate 101 is provided with a ring-shaped ceramic CBN layer 102 for grinding operations.

[0053] The ceramic CBN layer 102 has a structured region on its outer side away from the substrate 101, and the cross-sectional shape of the structured region is adapted to the target raceway.

[0054] Two arc-shaped grinding surfaces 103 are respectively provided on both sides of the structured region, and the two arc-shaped grinding surfaces 103 are symmetrically arranged on both sides of the structured region; a microstructure array 104 is provided on the grinding surface.

[0055] This invention comprises a hierarchical structure consisting of an annular substrate 101, an annular ceramic CBN layer 102, structured regions, and a microstructure array 104. The substrate 101, serving as the foundation of the CBN grinding wheel 1, possesses sufficient structural strength for assembly and connection with the grinding rod, ensuring the stability of the CBN grinding wheel 1 during grinding. The ceramic CBN layer 102, located on the outer ring of the substrate 101, is the core working layer for achieving the grinding function. The cross-sectional shape of its outer structured region precisely matches the target double-arc raceway, and symmetrically arranged arc-shaped grinding surfaces 103 on both sides ensure close contact with the workpiece raceway during grinding. The microstructure array 104 is positioned on the arc-shaped grinding surfaces 103 on both sides, covering an area no less than the area of ​​the double-arc structure, forming a discrete grinding working surface. This allows the grinding wheel to meet the high-load, high-precision processing requirements during profile grinding while alleviating the technical pain points of traditional profile grinding, balancing processing adaptability and processing effect. The microstructure array 104 discretizes the complete grinding surface into an array structure, significantly reducing the actual contact area between the grinding wheel and the workpiece. This reduces the grinding force and temperature generated during grinding, effectively minimizing grinding cracks and preventing workpiece surface damage due to high temperature and high stress, thus ensuring the grinding accuracy of the double-arc raceway. Simultaneously, the groove structure formed by the microstructure array 104 effectively accommodates grinding debris, preventing grinding wheel blockage caused by debris accumulation and improving chip removal efficiency. It also stores grinding fluid, promoting its entry into the grinding area, further enhancing cooling, and reducing the risk of grinding burns. This improves workpiece surface finish, reduces grinding wheel wear, and extends grinding wheel life.

[0056] In one embodiment of the present invention, the CBN grinding wheel 1 is a conformal disc structure, and the base 101 is a steel ring structure to ensure the overall structural strength; a circular mounting hole with a diameter of 20mm is provided at the center of the base 101 for mounting the CBN grinding wheel 1.

[0057] In one embodiment of the present invention, such as Figure 2 As shown, the CBN grinding wheel 1 has a radius R1 of 100mm and a width of b.

[0058] In one embodiment of the present invention, such as Figure 2 As shown, the arc-shaped grinding surface 103 has a double arc structure with an arc radius R2 of 6.604 mm and an arc eccentricity a of 0.43 mm.

[0059] In one embodiment of the present invention, such as Figure 2 As shown, the radius of the arc R2 and the eccentricity of the arc a are determined by the arc raceway parameters of the workpiece to be processed. According to the formula b=2R2+a+2c, the grinding wheel width b is calculated to be 14.6mm, where c is the reserved dressing allowance, which is 0.5-1mm.

[0060] In one embodiment of the present invention, the coverage area of ​​the microstructure array 104 is greater than or equal to the structural area of ​​the arc-shaped grinding surface 103, ensuring that the grinding working area of ​​the arc-shaped grinding surface 103 can all play a role through the microstructure array 104, avoiding the high stress and high temperature problems of traditional grinding in the uncovered area, ensuring that the processing effect of the entire grinding surface is uniform and consistent, and further improving the overall processing quality of the double arc raceway.

[0061] Further optimizing the design, the microstructure array 104 includes several microgrooves 105. These microgrooves 105 are uniformly arrayed along the circumference of the arc-shaped grinding surface 103, and are symmetrically arranged on the two arc-shaped grinding surfaces 103. The uniform array of microgrooves 105 along the circumference of the arc-shaped grinding surface 103, symmetrically distributed on both sides, ensures more balanced force and chip removal during grinding by the CBN grinding wheel 1, avoids local chip accumulation or uneven cooling, and reduces the risk of grinding wheel clogging. The symmetrical design of the microgrooves 105 on both sides is compatible with the symmetrical structure of the double arc-shaped raceway, ensuring consistent machining quality on both sides of the raceway, while improving the stability of the grinding wheel during rotation and reducing the impact of vibration on machining accuracy.

[0062] Further optimization of the scheme: the width of the microgroove 105 is w, the depth is D, the angle between the microgroove 105 and the radial direction of the CBN grinding wheel 1 is θ, and the spacing between adjacent microgrooves 105 is α, satisfying the following formula:

[0063]

[0064]

[0065]

[0066]

[0067] Where k1, k2, and k3 are proportional coefficients, R0 is the initial dressing allowance, N is the number of dressing cycles for CBN grinding wheel 1, Δd is the dressing depth per cycle, and F t For tangential grinding force, σ b d represents the fracture strength of the ceramic CBN layer 102. g H represents the abrasive grain size. b H represents the hardness of the grinding wheel bond. w The hardness of the workpiece material.

[0068] Further optimize the scheme and adjust the initial margin R0 to meet the requirements.

[0069]

[0070] Among them, E m For the manufacturing precision of grinding wheels, E i This refers to the installation deviation of the grinding wheel.

[0071] The scheme was further optimized so that the single trimming depth Δd satisfies

[0072]

[0073] Among them, R w Where n is the grinding wheel wear rate, L is the workpiece raceway length, and n is the grinding wheel wear rate. c a is the number of grinding operations within a dressing cycle. p This refers to the grinding depth.

[0074] In one embodiment of the present invention,

[0075] This invention discloses a method for preparing a microstructured CBN grinding wheel for double-circular-arc raceway grinding, comprising the following steps:

[0076] Step 1. Mount the CBN grinding wheel 1 to be processed on the grinding spindle 2, which can move along the X direction, and mount the dressing wheel 3 on the dressing spindle 4, which can move along the Z direction. Adjust the spatial position of the grinding spindle 2 and the dressing spindle 4 so that the axes of the grinding spindle 2 and the dressing spindle 4 are parallel and the center line of the CBN grinding wheel 1 is aligned with that of the dressing wheel 3.

[0077] Step 2. Based on the arc raceway parameters of the workpiece, obtain the radius R2 and the arc eccentricity a of the arc of the required arc grinding surface 103. The grinding spindle 2 and the dressing spindle 4 work together to achieve the initial dressing of the CBN grinding wheel 1 and obtain the CBN grinding wheel 1 without microstructure.

[0078] Step 3. Mount the laser galvanometer on the laser platform 6, which can move along the Z-axis. Adjust the spatial position of the laser platform 6 and the grinding spindle 2 so that the arc surface of the arc-shaped grinding surface 103 is located in the machined area of ​​the laser 5. When the width H of the arc structure on one side of the CBN grinding wheel 1 in the Z-axis is less than or equal to 2*ZR At that time, one-time processing; when the width H of the single-sided circular arc structure of CBN grinding wheel 1 in the z direction is greater than 2*Z R The process is divided into multiple steps, with the number of steps being n. In a single processing cycle, the laser scanning trajectory is defined as a raster scan, with the scanning direction along the Y-axis and the offset direction along the X-axis. By adjusting the density of the scan lines in the raster scan (X-axis displacement), the scanning density is increased in areas of low energy (large defocus) and decreased in areas of high energy (close focus), thereby achieving uniform global energy deposition. In multiple processing cycles, the laser galvanometer is moved along the Z-axis of the machine tool, moving the laser focus to the center of each processing layer each time. Then, each layer is processed based on the optimized scanning trajectory.

[0079] Step 4. Use laser 5 to process microstructures on the arc surface of the arc-shaped grinding surface 103. Adjust the position of laser platform 6 so that the arc-shaped grinding surface 103 to be processed is located at the Rayleigh length Z of the laser. R Inside, the microstructure array 104 is processed layer by layer until the surface of the arc-shaped grinding surface 103 has the microstructure array 104, thus completing the processing of one side of the microstructure array 104.

[0080] Step 5. Turn the CBN grinding wheel 1 over and repeat steps 3 and 4 to complete the preparation of the microstructured CBN grinding wheel 1.

[0081] In one embodiment of the present invention, in step one, the CBN grinding wheel 1 to be processed is a 1F1 type ceramic grinding wheel with a diameter of 100mm, a thickness of 14.6mm, and a grit size of 120 mesh; the dressing wheel 3 is a diamond disc wheel with a diameter 1.2-1.5 times that of the CBN grinding wheel, an arc radius r of 1mm, and a grit size of 1 / 2-1 / 3 that of the CBN grinding wheel.

[0082] To further optimize the scheme, in step one, the dressing wheel 3 is used to adjust the tool on the left and right sides of the CBN grinding wheel 1, and the coordinate positions of the dressing wheel 3 are recorded as a1 and a2 respectively. The dressing wheel 3 is then adjusted to the coordinate position A0 of (a1+a2) / 2 to achieve center line alignment.

[0083] In one embodiment of the present invention, the rotational speed of the CBN grinding wheel 1 is 3000-4000 rpm, and the rotational speed of the dressing wheel 3 is 2000-3000 rpm, so that the dressing speed ratio is between 0.5 and 0.7. The dressing method is adopted, the dressing depth of each combined relative motion is 2-3 μm, and the axial feed rate is 15-25 mm / min.

[0084] In one embodiment of the present invention, in step two, the dressing spindle 4 is adjusted to the coordinate position A1 of (a1+a2+a) / 2+R2+r, and the grinding spindle 2 is moved until the CBN grinding wheel 1 contacts the dressing wheel 3 to achieve dressing and tool setting. Then, the grinding spindle 2 and the dressing spindle 4 work together to run a double arc dressing trajectory to achieve the initial dressing of the CBN grinding wheel.

[0085] In one embodiment of the present invention, before laser processing in step three, the energy distribution of a single-pulse laser spot is first established based on the spatial interaction between the laser and the arc surface of the grinding wheel, such as... Figure 6 , Figure 7 As shown, due to the arc-shaped structure of the grinding wheel, the laser cannot be incident at an angle to the grinding wheel surface. The laser energy will be different under different laser incident angles. A laser energy distribution model is established. In order to ensure that the span and depth of the microgrooves processed along the arc direction of the grinding wheel are uniform, the density of the scanning lines (X-direction displacement) in the grating scanning is adjusted. The scanning density is increased in the low energy area (large defocus) and decreased in the high energy area (close focus), thereby achieving uniformity of global energy deposition.

[0086] In one embodiment of the present invention, an energy field model is first established, and then the optimal scanning trajectory is optimized to achieve uniformity of global energy deposition.

[0087]

[0088] Peak intensity (based on energy conservation):

[0089]

[0090] The local strength is:

[0091]

[0092] The total energy field E is the sum of the contributions of all pulses j on all scan lines m:

[0093]

[0094] The laser scanning trajectory is defined as a raster scan, with the scanning direction along the y-axis and the offset direction along the x-axis. The initial x-axis offset can be set to be uniform, and the offset in the x-axis is adjusted according to the energy distribution results during subsequent optimization. No offset is made in the z-axis. Processing is achieved through defocusing within the Rayleigh length. Figure 8 As shown.

[0095] Using the standard deviation of laser energy as the uniformity optimization index,

[0096]

[0097]

[0098] in, The total number of voxels.

[0099] X-coordinate set of scan lines These are the variables we want to optimize:

[0100]

[0101] in, It represents the total number of scan lines.

[0102] Calculate the objective function pair Partial derivatives:

[0103]

[0104] The SLSQP numerical algorithm is used for continuous iterative optimization and updating. Variables, such as the comparison of laser energy and spacing before and after optimization. Figure 9 , Figure 10 As shown, the specific flowchart is as follows: Figure 11 As shown.

[0105] In one embodiment of the present invention, in step three, the laser 5 is a picosecond laser with a power of 10-20W, a repetition frequency of 700-800kHz, a pulse width of 15-200ps, and a laser wavelength of 1064nm.

[0106] In one embodiment of the present invention, in step four, microstructure processing of one side of the CBN grinding wheel 1 is performed according to the designed laser scanning trajectory and the corresponding laser processing parameters.

[0107] In one embodiment of the present invention, in step five, the CBN grinding wheel 1 is flipped over, and the tilt angle of the microstructure array is changed to -θ. Steps three and four are repeated to complete the preparation of the microstructured CBN grinding wheel with bilateral symmetry.

[0108] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0109] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A microstructured CBN grinding wheel for double circular arc raceway grinding, characterized in that: The substrate (101) includes an annularly arranged base, which serves as the base of the CBN grinding wheel (1) and is used to connect with the grinding rod. The outer ring of the substrate (101) is provided with an annular ceramic CBN layer (102) for grinding operations. The ceramic CBN layer (102) has a structured region on its outer side away from the substrate (101), and the cross-sectional shape of the structured region is adapted to the target raceway. Arc-shaped grinding surfaces (103) are respectively provided on both sides of the structured region, and the two arc-shaped grinding surfaces (103) are symmetrically arranged on both sides of the structured region; a microstructure array (104) is provided on the arc-shaped grinding surfaces (103).

2. The microstructured CBN grinding wheel for double circular arc raceway grinding according to claim 1, characterized in that: The microstructure array (104) includes a plurality of microgrooves (105), which are uniformly arrayed along the circumferential direction of the arc-shaped grinding surface (103), and the microgrooves (105) located on the two arc-shaped grinding surfaces (103) are symmetrically arranged.

3. The microstructured CBN grinding wheel for double circular arc raceway grinding according to claim 2, characterized in that: The microgroove (105) has a width of w and a depth of D. The angle between the microgroove (105) and the radial direction of the CBN grinding wheel (1) is θ, and the spacing between adjacent microgrooves (105) is α, satisfying the following formula: Where k1, k2, and k3 are proportional coefficients, R0 is the initial dressing allowance, N is the number of dressing cycles for the CBN grinding wheel (1), Δd is the single dressing depth, and F t For tangential grinding force, σ b d represents the fracture strength of the ceramic CBN layer (102). g H represents the abrasive grain size. b H represents the hardness of the grinding wheel bond. w The hardness of the workpiece material.

4. The microstructured CBN grinding wheel for double circular arc raceway grinding according to claim 3, characterized in that: The initial trimming allowance R0 satisfies Among them, E m For the manufacturing precision of grinding wheels, E i This refers to the installation deviation of the grinding wheel.

5. The microstructured CBN grinding wheel for double circular arc raceway grinding according to claim 3, characterized in that: The single trimming depth Δd satisfies Among them, R w Where n is the grinding wheel wear rate, L is the workpiece raceway length, and n is the grinding wheel wear rate. c a is the number of grinding operations within a dressing cycle. p This refers to the grinding depth.

6. A method for preparing a microstructured CBN grinding wheel for double-circular-arc raceway grinding, used to prepare the microstructured CBN grinding wheel for double-circular-arc raceway grinding as described in any one of claims 1-5, characterized in that, Includes the following steps: Step 1. Mount the CBN grinding wheel (1) to be processed on the grinding spindle (2) which can move along the X direction, and mount the dressing wheel (3) on the dressing spindle (4) which can move along the Z direction. Adjust the spatial position of the grinding spindle (2) and the dressing spindle (4) so ​​that the axes of the grinding spindle (2) and the dressing spindle (4) are parallel and the center line of the CBN grinding wheel (1) is aligned with that of the dressing wheel (3). Step 2. Based on the arc raceway parameters of the workpiece, obtain the radius R2 and eccentricity a of the arc of the required arc grinding surface (103). The grinding spindle (2) and the dressing spindle (4) work together to achieve the initial dressing of the CBN grinding wheel (1) and obtain the CBN grinding wheel (1) without microstructure. Step 3. Mount the laser galvanometer on the laser platform (6) that can move along the Z direction, and adjust the spatial position of the laser platform (6) and the grinding spindle (2) so that the arc surface of the arc-shaped grinding surface (103) is located in the machinable area of ​​the laser (5). When the width H of the arc structure on one side of the CBN grinding wheel (1) in the Z direction is less than or equal to 2*Z R At that time, one-time processing; when the width H of the single-sided circular arc structure of the CBN grinding wheel (1) in the z direction is greater than 2*Z R At that time, the process is divided into multiple steps; Step 4. Use a laser (5) to process microstructures on the arc surface of the arc-shaped grinding surface (103), and adjust the position of the laser platform (6) so that the arc-shaped grinding surface (103) to be processed is located at the Rayleigh length Z of the laser. R Inside, the microstructure array (104) is processed layer by layer until the surface of the arc-shaped grinding surface (103) has a microstructure array (104), and the processing of one side of the microstructure array (104) is completed; Step 5. Turn the CBN grinding wheel (1) over and repeat steps 3 and 4 to complete the preparation of the microstructured CBN grinding wheel (1).

7. The method for preparing a microstructured CBN grinding wheel for double-circular-arc raceway grinding according to claim 6, characterized in that: In step one, the dressing wheel (3) is used to adjust the tool on the left and right sides of the CBN grinding wheel (1). The coordinate positions of the dressing wheel (3) are recorded as a1 and a2 respectively. The dressing wheel (3) is adjusted to the coordinate position A0 of (a1+a2) / 2 to achieve center line alignment.

8. The method for preparing a microstructured CBN grinding wheel for double circular arc raceway grinding according to claim 6, characterized in that: In step two, the dressing spindle (4) is adjusted to coordinate position A1 (a1+a2+a) / 2+R2+r, and the grinding spindle (2) is moved until the CBN grinding wheel (1) contacts the dressing wheel (3) to achieve dressing and tool setting. Then the grinding spindle (2) and the dressing spindle (4) run in conjunction to achieve the initial dressing of the CBN grinding wheel (1).

9. The method for preparing a microstructured CBN grinding wheel for double circular arc raceway grinding according to claim 6, characterized in that: In step three, when multiple processing steps are performed, the number of processing steps is n: 。 10. The method for preparing a microstructured CBN grinding wheel for double circular arc raceway grinding according to claim 6, characterized in that: In step three, laser energy field modeling is performed, and the laser processing trajectory is optimized by varying the spacing. The X-direction displacement is achieved by adjusting the density of the scan lines in the grating scan. The scan density is increased in the low-energy region and decreased in the high-energy region, thereby achieving uniformity of global energy deposition.

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