Grinding wheel manufacturing method and grinding wheel

Abstract

To provide an adhesive force of a grind stone with respect to an annular base.SOLUTION: A manufacturing method of a grinding wheel includes: an irregularity forming step for forming irregularities on a side surface and / or a bottom surface of an annular groove by imparting ultrasonic vibrations to the annular groove of an annular base where the annular groove is formed on one surface along a circumferential direction from an ultrasonic vibration imparting unit via water; and a grind stone fixing step for fixing a plurality of grind stones to the annular groove with adhesive after the irregularity forming step.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a grinding wheel used when grinding a workpiece, and to a grinding wheel. [Background technology]

[0002] Electronic devices such as mobile phones and personal computers are equipped with device chips that include devices such as ICs (Integrated Circuits). When manufacturing device chips, for example, the backside of a wafer on which multiple devices are formed on the front side is ground to thin the wafer, and then the wafer is cut and divided into device units.

[0003] A grinding machine is used to grind a wafer. For example, a grinding machine is known that performs rough grinding on the backside of a wafer using a rough grinding unit and then performs finish grinding using a finish grinding unit (see Patent Document 1).

[0004] The rough grinding unit has a first spindle arranged substantially parallel to the vertical direction. A rough grinding wheel is attached to the lower end of the first spindle. Similarly, the finish grinding unit has a second spindle arranged substantially parallel to the vertical direction. A finish grinding wheel is attached to the lower end of the second spindle.

[0005] Grinding wheels, such as rough grinding wheels and finish grinding wheels, have an annular base made of metal. An annular groove having a predetermined width is formed on one side of the annular base along the circumferential direction of the annular base. A plurality of grinding wheels (hereinafter, grinding wheels will be simply referred to as grinding wheels) are arranged in this annular groove at approximately equal intervals along the circumferential direction of the annular base.

[0006] Each grinding wheel is fixed to the annular base with adhesive. However, the width of the annular groove is only a few millimeters, and more than half of each grinding wheel protrudes from one side of the annular base in the thickness direction of the cutting edge. Therefore, if the grinding wheel is not fixed to the annular base with sufficient adhesive strength, the grinding wheel may fall off the annular base during grinding. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-288881 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made in view of the above problems, and has as its object to improve the adhesive strength of the grinding wheel to the annular base. [Means for solving the problem]

[0009] According to one aspect of the present invention, there is provided a method of manufacturing a grinding wheel, comprising the steps of: Made of metal material A method for manufacturing a grinding wheel is provided, which includes an unevenness forming step in which an annular groove is formed in one surface of an annular base along the circumferential direction, and unevenness is formed on one or both of the side and bottom surfaces of the annular groove by applying ultrasonic vibrations via water from an ultrasonic vibration imparting unit to the annular groove, and a grinding wheel fixing step in which, after the unevenness forming step, multiple grinding wheels are fixed to the annular groove with an adhesive.

[0010] According to another aspect of the present invention, there is provided a grinding wheel comprising: Made of metal materialThe grinding wheel includes an annular base having an annular groove on one surface thereof arranged along the circumferential direction, and a plurality of grinding stones fixed to the annular groove with an adhesive, wherein a first periodic asperity is formed on the side surface of the annular groove in a thickness direction perpendicular to the circumferential direction, and a second periodic asperity is formed on the bottom surface of the annular groove in a radial direction perpendicular to the circumferential direction and the thickness direction, and a third asperity having a depth smaller than that of the first asperity and the second asperity is formed on one or both of the side surface and the bottom surface of the annular groove. [Effects of the Invention]

[0011] In one embodiment of the present invention, a method for manufacturing a grinding wheel includes applying ultrasonic vibrations to the annular groove of an annular base via water from an ultrasonic vibration applying unit, thereby forming irregularities on one or both of the side and bottom surfaces of the annular groove (irregularity forming step). The irregularities formed in the annular groove by applying ultrasonic vibrations increase the contact area between the annular base and the adhesive, thereby improving the adhesive strength of the grinding wheel to the annular base.

[0012] In addition, in a grinding wheel according to another aspect of the present invention, third asperities having a depth smaller than that of the first and second asperities are formed on one or both of the side and bottom surfaces of the annular groove. The third asperities increase the contact area between the annular base and the adhesive, thereby improving the adhesive strength of the grinding wheel to the annular base. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a flow diagram of a method for manufacturing a grinding wheel. [Figure 2] 10A and 10B are diagrams illustrating a step of forming irregularities. [Figure 3] FIG. 3(A) is an enlarged cross-sectional view of the annular groove, and FIG. 3(B) is an enlarged view of region A in FIG. 3(A). [Figure 4] FIG. [Figure 5] FIG. 2 is a perspective view of a grinding wheel. [Figure 6] FIG. 1 is a schematic diagram of a universal testing machine. [Figure 7] 10 is a graph showing test results of a bending test of a cantilever grinding wheel. [Figure 8] FIG. [Figure 9] FIG. 9(A) is an enlarged photograph of region B to which ultrasonic vibration is not applied, and FIG. 9(B) is a schematic diagram of the cross-sectional outline of the disk-shaped base. [Figure 10] FIG. 10(A) is an enlarged photograph of region B after cutting and sandblasting, and FIG. 10(B) is a schematic diagram of the cross-sectional outline of the disk-shaped base. [Figure 11] FIG. 11(A) is an enlarged photograph of region B after cutting and application of ultrasonic vibration, and FIG. 11(B) is a schematic diagram of the cross-sectional outline of the disk-shaped base. DETAILED DESCRIPTION OF THE INVENTION

[0014] An embodiment according to one aspect of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a flow diagram of a method for manufacturing a grinding wheel 2 (see Fig. 5). First, with reference to Figs. 4 and 5, the structure of the grinding wheel 2 in which a plurality of grinding wheels 6 are fixed to an annular base 4 will be described.

[0015] The grinding wheel 2 has an annular base 4 made of a metal material such as an aluminum alloy. The annular base 4 has an annular first surface 4a and an annular second surface 4b arranged generally parallel to each other. A grinding stone 6 (described later) is fixed to the first surface 4a of the annular base 4 (the upper surface in FIG. 5).

[0016] In contrast, the other surface 4b (the lower-upper surface side in FIG. 5) is fixed to a wheel mount (not shown) with bolts, etc. The outer diameters of the one surface 4a and the other surface 4b are approximately the same, and the outer peripheral side surface of the annular base 4 is a cylindrical side surface that is approximately perpendicular to the one surface 4a and the other surface 4b.

[0017] On the other hand, the inner diameter of the one surface 4a is larger than the inner diameter of the other surface 4b. Therefore, an inclined surface is formed on part of the inner peripheral side surface of the annular base 4. An opening 4c is formed in the center of the annular base 4 in the radial direction 4B, penetrating from the one surface 4a to the other surface 4b.

[0018] An annular groove 4d is formed on one surface 4a along the circumferential direction 4A of the annular base 4. The width of the annular groove 4d is a predetermined value, for example, not less than 2.0 mm and not more than 4.0 mm. A plurality of grinding stones 6 are arranged at approximately equal intervals in the annular groove 4d.

[0019] Each grinding wheel 6 is formed by mixing a binder such as metal, ceramics, or resin with superabrasive grains such as diamond or cBN (cubic boron nitride), and then molding, firing, etc. Each grinding wheel 6 has a width 6a (i.e., segment width) that is approximately the same as the width of the annular groove 4d.

[0020] The base end 6b (see FIG. 4) of each grinding wheel 6 is fixed to the annular groove 4d with an adhesive 7. The adhesive 7 in this embodiment is a thermosetting resin such as an epoxy resin, but the adhesive 7 is not limited to this example.

[0021] At least two-thirds of the height 6c of the fixed grinding wheel 6 protrudes from the surface 4a. The length of the area of ​​the height 6c of the grinding wheel 6 that protrudes from the surface 4a is called the segment height. The segment height is a predetermined value, for example, between 4.0 mm and 15.0 mm.

[0022] A plurality of grinding fluid supply ports 8 are formed inward of the annular groove 4d on one surface 4a in the radial direction 4B of the annular base 4. The grinding fluid supply ports 8 are arranged at approximately equal intervals along the circumferential direction 4A of the annular base 4. During grinding, grinding fluid (not shown) such as pure water is supplied to the grinding wheel 6 from each grinding fluid supply port 8.

[0023] Next, a method for manufacturing the grinding wheel 2 will be described with reference to the flow diagram shown in Fig. 1. In the method for manufacturing the grinding wheel 2 according to this embodiment, first, as shown in Fig. 2, ultrasonic vibrations are applied to the annular groove 4d via water 10, such as pure water, to form irregularities in the annular groove 4d (irregularity forming step S10). Note that, hereinafter, the irregularities formed in the annular groove 4d by applying ultrasonic vibrations in the irregularity forming step S10 will be referred to as third irregularities 4e3 (see Fig. 3(B)).

[0024] 2 is a diagram showing the unevenness forming step S10. In the unevenness forming step S10, first, the annular base 4 is immersed in a water tank 12 containing a predetermined amount of water 10, with one surface 4a facing upward. Then, with the lower end 16a of the vibration amplification transmission part 16 of the ultrasonic vibration imparting unit 14 positioned in the annular groove 4d, ultrasonic vibration is imparted from the vibration amplification transmission part 16.

[0025] The ultrasonic vibration imparting unit 14 of this embodiment has a bolt-clamped Langevin-type transducer (BLT) including a piezoelectric element. A conical horn (vibration amplifier) ​​for amplifying ultrasonic vibrations is connected to the BLT.

[0026] Furthermore, a cylindrical vibration transmission rod (vibration transmission section) for transmitting the ultrasonic vibrations amplified by the horn is connected to the tip of the horn, and the horn and vibration transmission rod constitute the vibration amplification and transmission section 16. However, the configuration of the ultrasonic vibration imparting unit 14 is not limited to this example.

[0027] An oscillator (not shown) that generates a high-frequency electric signal is electrically connected to the ultrasonic vibration imparting unit 14. The high-frequency electric signal supplied from the oscillator causes the ultrasonic vibration imparting unit 14 to generate ultrasonic vibrations.

[0028] In the unevenness forming step S10 of this embodiment, the frequency of the ultrasonic vibration is set to a predetermined value of 16 kHz to 100 kHz (for example, 20 kHz), and the output is set to a predetermined value of 5.0 W to 100 W (for example, 30 W).

[0029] Furthermore, ultrasonic vibrations are applied to the annular base 4 for at least one minute (more preferably at least three minutes) while the ultrasonic vibration imparting unit 14 is kept stationary, and then the ultrasonic vibration imparting unit 14 is translated a predetermined distance along the circumferential direction 4A of the annular groove 4d.

[0030] In this way, by alternately repeating the application of ultrasonic vibrations and the translation of the ultrasonic vibration application unit 14, ultrasonic vibrations are applied to the entire annular groove 4d in the circumferential direction 4A. 1A and outer peripheral side 4d 1B ) and the bottom surface 4d2, a third irregularity 4e3 is formed on one or both of them.

[0031] The water 10 does not contain abrasive grains or the like that may scratch the annular base 4. Therefore, it is presumed that the third irregularities 4e3 are formed by, for example, shock waves (i.e., cavitation effect) generated by the bursting of bubbles.

[0032] As shown in FIG. 3(A), the side surface 4d1 (inner peripheral side surface 4d 1A and outer peripheral side 4d 1B ) and the bottom surface 4d2, periodic unevenness remains, which was formed when cutting the annular base 4 using a machining center.

[0033] More specifically, the inner peripheral side surface 4d 1A and outer peripheral side 4d 1B First irregularities 4e1 are formed periodically along the thickness direction 4C of the annular base 4. The first irregularities 4e1 in this embodiment are a plurality of grooves that are approximately parallel to one another and extend along the circumferential direction 4A.

[0034] Similarly, second irregularities 4e2 are formed periodically on the bottom surface 4d2 along the radial direction 4B of the annular base 4. The second irregularities 4e2 in this embodiment are also a plurality of grooves that are approximately parallel to one another and extend along the circumferential direction 4A. Fig. 3(A) is an enlarged cross-sectional view of the annular groove 4d.

[0035] 3A, the circumferential direction 4A, the radial direction 4B, and the thickness direction 4C of the annular base 4 are perpendicular to one another. For ease of explanation, the first irregularities 4e1 on the side surface 4d1 and the second irregularities 4e2 on the bottom surface 4d2 are exaggerated in FIG. 3A, but in reality, the first irregularities 4e1 and the second irregularities 4e2 are very small.

[0036] For example, the first and second asperities 4e1 and 4e2 have a period (pitch) of 80 μm to 100 μm (e.g., 90 μm) and a depth of 20 μm to 100 μm (e.g., 30 μm). Therefore, the first and second asperities 4e1 and 4e2 are generally almost invisible to the naked eye.

[0037] Fig. 3(B) is an enlarged view of region A on bottom surface 4d2 in Fig. 3(A). Fig. 3(B) also shows the pitch 4f and depth 4g of second asperities 4e2 formed on bottom surface 4d2. Pitch 4f is, for example, the distance between the peaks of two adjacent mountains, but may also be the distance between the bottoms of two adjacent valleys.

[0038] In addition, the depth 4g in this embodiment is the distance between the highest peak and the lowest valley within a predetermined length (i.e., the reference length) extracted from the roughness curve, and is also referred to as the maximum height Rz (JIS B 0601:2013, ISO 4287:1997) and corresponds to the maximum height Ry (JIS B 0601:1994).

[0039] By applying ultrasonic vibration to the annular groove 4d in the irregularity forming step S10, third irregularities 4e3 are formed on one or both of the side surface 4d1 and the bottom surface 4d2, as shown in FIG. 3(B).

[0040] The third asperity 4e3 on the bottom surface 4d2 is composed of the surface of the periodic second asperity 4e2 and a plurality of holes formed on the bottom surface 4d2 in the asperity forming step S10. Similarly, the third asperity 4e3 on the side surface 4d1 is composed of the surface of the periodic first asperity 4e1 and a plurality of holes formed on the side surface 4d1 in the asperity forming step S10.

[0041] The third asperity 4e3 has a depth 4h (e.g., 10 μm) that is smaller than the depth 4g of the first asperity 4e1 and the second asperity 4e2. For example, as shown in FIG. 3B, the depth 4h of the third asperity 4e3 formed on the surface of the periodic second asperity 4e2 is defined as the maximum depth of the holes in the normal direction to the surface of the second asperity 4e2 when no holes are formed.

[0042] The third asperity 4e3 is formed substantially randomly, unlike the periodic first asperity 4e1 and second asperity 4e2. In this embodiment, the third asperity 4e3 is formed on both the side surface 4d1 and the bottom surface 4d2, but may be formed only on the bottom surface 4d2 or only on the side surface 4d1.

[0043] After the unevenness forming step S10, the annular base 4 is removed from the water tank 12 and dried. Then, after supplying liquid adhesive 7 to the annular groove 4d, multiple grinding wheels 6 are inserted into the annular groove 4d (see FIG. 4). Next, the adhesive 7 is solidified, thereby fixing each grinding wheel 6 to the annular groove 4d with the adhesive 7 (grinding wheel fixing step S20). FIG. 4 is a diagram showing the grinding wheel fixing step S20.

[0044] The adhesive 7 is not limited to a thermosetting resin, but may be a two-part mixture type room temperature curing resin that starts curing when a base agent and a curing agent are mixed, or an ultraviolet curing resin that starts curing when irradiated with ultraviolet light.

[0045] Fig. 5 is a perspective view of the grinding wheel 2 manufactured according to the flow diagram shown in Fig. 2. In this embodiment, the third asperities 4e3 formed in the annular groove 4d by applying ultrasonic vibrations increase the contact area between the annular base 4 and the adhesive 7, thereby improving the adhesive strength (adhesion) of the grinding stone 6 to the annular base 4.

[0046] In the unevenness forming step S10, the annular base 4 may be placed on a rotatable table, and the table may be rotated relatively slowly at a predetermined rotation speed. Alternatively, instead of rotating the table, a ring-shaped vibration transmitting unit (not shown) that can fit into the annular groove 4d may be used as the vibration amplifying and transmitting unit 16, and ultrasonic vibrations may be applied to the entire annular groove 4d simultaneously.

[0047] In the unevenness forming process S10, instead of immersing the annular base 4 in a water tank 12 containing water 10, ultrasonic vibrations may be applied to the annular groove 4d while supplying water 10, such as pure water, from a nozzle (not shown) between the vibration amplification transmission section 16 and the annular groove 4d.

[0048] Next, the experimental results of the bending test will be described with reference to Fig. 6 to Fig. 11. In this experiment, a universal testing machine (model number: AG50-kNG) 20 manufactured by Shimadzu Corporation was used. First, the configuration of the universal testing machine 20 will be described with reference to Fig. 6. Fig. 6 is a schematic diagram of the universal testing machine 20.

[0049] The universal testing machine 20 has an indenter 22 that can be lowered along the Z-axis direction. The indenter 22 has a cylindrical shape with a diameter of 3 mm and is arranged so that the longitudinal direction of the cylinder is perpendicular to the Z-axis direction. In this experiment, the test piece 11 was fixed in a vice 24 provided at the bottom of the universal testing machine 20, and the indenter 22 was lowered at 1 mm / min.

[0050] The test piece 11 used in this experiment had a disk-shaped base 13 made of an aluminum alloy. One surface 13a of the disk-shaped base 13 was machined using a machining center, and periodic irregularities remained, similar to the side surface 4d1 and bottom surface 4d2 of the above-mentioned annular base 4 (see Figures 9(A), 9(B), etc.).

[0051] The pitch of the irregularities formed on one surface 13a of the disk-shaped base 13 is approximately 90 μm, and the depth (Rz) of the irregularities is approximately 30 μm. One surface 6d of the grinding wheel 6 corresponding to the base end 6b side of the grinding wheel 6 inserted into the annular groove 4d was fixed to one surface 13a of the disk-shaped base 13 with adhesive 7.

[0052] In addition, we prepared a disk-shaped base 13 that had not undergone the above-mentioned unevenness formation process S10, and a disk-shaped base 13 to which ultrasonic vibrations had been applied using the unevenness formation process S10 in a predetermined area of ​​one surface 13a where the adhesive 7 was applied.

[0053] Specifically, two first test pieces 11 were prepared in which a grinding wheel 6 was fixed with adhesive 7 to a disk-shaped base 13 that had not undergone the above-mentioned unevenness forming process S10, and two second test pieces 11 in which the ultrasonic vibration was applied for 30 seconds in the unevenness forming process S10.

[0054] Furthermore, two third test pieces 11 were prepared by applying ultrasonic vibration for one minute in the unevenness forming process S10, and two fourth test pieces 11 were prepared by applying ultrasonic vibration for three minutes in the unevenness forming process S10.

[0055] The adhesive 7 was a one-component heat-curing epoxy resin. The adhesive 7 was applied at a rate of 160 g / m2 to the area of ​​the surface 13a corresponding to the surface 6d of the grinding wheel 6. 2 and solidified at 120° C. for 2 hours, thereby fixing the grindstone 6 in a cantilevered state to the one surface 13a.

[0056] Then, with the disk-shaped base 13 fixed by the vice 24, the indenter 22 was lowered approximately perpendicularly to the side surface of the grinding wheel 6. At this time, the maximum stress (MPa) applied to the indenter 22 was measured until the adhesive 7 broke and the grinding wheel 6 peeled off from the disk-shaped base 13.

[0057] Fig. 7 is a graph showing the test results of the bending test of the cantilever-shaped grinding wheel 6. Fig. 7 shows the smaller value (i.e., the minimum value) of the maximum stresses measured when the grinding wheel 6 peeled off from the disk-shaped base 13 for each of the first to fourth test pieces 11.

[0058] The minimum value of the maximum stress applied to the indenter 22 in the tests on the two first test pieces 11 was 122.95 MPa. The minimum value of the maximum stress in the tests on the two second test pieces 11 was 122.10 MPa.

[0059] Furthermore, the minimum value of the maximum stress in the test on the two third test pieces 11 was 127.35 MPa, and the minimum value of the maximum stress in the test on the two fourth test pieces 11 was 152.85 MPa.

[0060] Thus, the longer the time for which ultrasonic vibrations are applied, the more improved the adhesive strength (adhesion) of the adhesive 7 that bonds the disc-shaped base 13 and the grinding wheel 6. Based on the experimental results, it can be said that the time for which ultrasonic vibrations are applied to the area where the grinding wheel 6 is fixed is preferably 1 minute or more, and more preferably 3 minutes or more.

[0061] Next, the observation results of one surface 13a of the disk-shaped base 13 used in the above-mentioned experiment will be described. Fig. 8 is a plan view of the disk-shaped base 13. Enlarged photographs of a part of region B of the one surface 13a where the grinding wheel 6 is fixed with adhesive 7 are shown in Figs. 9(A), 10(A), and 11(A), respectively.

[0062] Fig. 9(A) is an enlarged photograph of region B on one surface 13a of disk-shaped base 13 (corresponding to first test piece 11) that has been machined using a machining center but not subjected to ultrasonic vibration. Fig. 9(B) is a schematic cross-sectional view of the outline of disk-shaped base 13 in a plane parallel to predetermined direction C and perpendicular to one surface 13a in Fig. 9(A).

[0063] 9(B) correspond to the valley bottoms of the periodic asperities 13b1 formed on the surface 13a. These periodic asperities 13b1 correspond to the first asperities 4e1 and second asperities 4e2 of the annular groove 4d described above.

[0064] Fig. 10(A) is an enlarged photograph of region B on one surface 13a of the disk-shaped base 13 after cutting using a machining center and sandblasting. Fig. 10(B) is a schematic diagram of the outline of the cross section of the disk-shaped base 13 on a plane parallel to the predetermined direction C in Fig. 10(A) and perpendicular to one surface 13a.

[0065] The dashed lines in Fig. 10(B) indicate that the periodic irregularities 13b1 formed on the surface 13a have disappeared. Also, as shown in Fig. 10(B), minute irregularities 13c are formed in a substantially random pattern on the surface 13a after sandblasting.

[0066] For the sandblasting process, a commercially available sandblasting device was used to process the disk-shaped base 13 for 3 minutes at 0.5 MPa using polygonal particles made of white alundum (WA) (i.e., fused alumina) material and having a central particle size (i.e., 50% diameter, median diameter) of 45 μm or more and 75 μm or less.

[0067] The above-mentioned bending test was also carried out on the sandblasted test pieces 11. In the test on the two sandblasted test pieces 11, the minimum value of the maximum stress was 136.85 MPa.

[0068] In this way, sandblasting can contribute to improving the adhesive strength of the adhesive 7 that bonds the disk-shaped base 13 and the grinding wheel 6. However, when sandblasting is performed, powder is sprayed onto the disk-shaped base 13 at high pressure, so the powder adheres to the disk-shaped base 13.

[0069] Therefore, when sandblasting is applied to the annular base 4, cleaning is required after processing to remove the powder from the annular base 4, which requires additional man-hours. The same problem also occurs when sandblasting is applied to the annular base 4.

[0070] In contrast, when the irregularities are formed by applying ultrasonic vibrations as in the irregularity forming step S10 described above, no abrasive grains are used, which has the advantage that cleaning after the irregularities are formed is not required.

[0071] Fig. 11(A) is an enlarged photograph of region B after cutting using a machining center and application of ultrasonic vibrations. Fig. 11(A) is a photograph of the disk-shaped base 13 (corresponding to the fourth test piece 11) to which ultrasonic vibrations were applied for 3 minutes in the concave-convex forming step S10.

[0072] Fig. 11(B) is a schematic diagram of the cross-sectional contour of the disk-shaped base 13 in a plane parallel to the predetermined direction C in Fig. 11(A) and perpendicular to the surface 13a. The dashed lines in Fig. 11(B) correspond to the valley bottoms of the periodic irregularities 13b1 formed on the surface 13a. As described above, the periodic irregularities 13b1 correspond to the first irregularities 4e1 and the second irregularities 4e2.

[0073] As shown in Figure 11(B), by applying ultrasonic vibrations, it is possible to form irregularities 13b2 (corresponding to the third irregularities 4e3) that are finer than the periodic irregularities 13b1 on one surface 13a formed by cutting processing, while leaving the periodic irregularities 13b1.

[0074] The minute irregularities 13b2 formed by applying ultrasonic vibrations increase the contact area between the disk-shaped base 13 and the adhesive 7, which is thought to improve the adhesive strength (adhesion) of the grinding wheel 6 to the disk-shaped base 13.

[0075] The technical scope of the present invention is not limited to the scope described in the above-described embodiments. The structures, methods, etc. according to the above-described embodiments can be appropriately modified and implemented without departing from the scope of the object of the present invention.

[0076] In one example, in the above-mentioned unevenness forming process S10, the annular base 4 was immersed in water 10 in a water tank 12 so that one surface 4a of the annular base 4 faced upward, but as long as ultrasonic vibrations can be applied through the water 10, one surface 4a of the annular base 4 may face sideways or downward. [Explanation of symbols]

[0077] 2: Grinding wheel, 4: Annular base, 4A: Circumferential direction, 4B: Radial direction, 4C: Thickness direction 4a: One side, 4b: Other side, 4c: Opening 4d: annular groove, 4d1: side, 4d 1A : Inner periphery side, 4d 1B : outer side, 4d2: bottom 4e1: First unevenness, 4e2: Second unevenness, 4e3: Third unevenness (unevenness) 4f: pitch, 4g: depth, 4h: depth 6: grinding stone, 6a: width, 6b: base end, 6c: height, 6d: one surface 7: Adhesive 8: Grinding fluid supply port 10: Water, 12: Aquarium 11: Test piece 13: disc-shaped base, 13a: one surface, 13b1, 13b2, 13c: uneven 14: ultrasonic vibration imparting unit, 16: vibration amplification and transmission part, 16a: lower end 20: Universal testing machine, 22: Indenter, 24: Vice A, B: Area, C: Predetermined direction S10: unevenness forming process, S20: grindstone fixing process

Claims

1. A method for manufacturing a grinding wheel, comprising: an annular base formed of a metal material and having an annular groove formed along a circumferential direction on one surface thereof, and applying ultrasonic vibrations to the annular groove from an ultrasonic vibration applying unit via water to form irregularities on one or both of a side surface and a bottom surface of the annular groove; a grindstone fixing step of fixing a plurality of grindstones in the annular groove with an adhesive after the concave-convex forming step; A method for manufacturing a grinding wheel, comprising:

2. A grinding wheel comprising: an annular base formed of a metal material and having an annular groove formed on one surface thereof along a circumferential direction; a plurality of grinding wheels fixed in the annular groove with an adhesive; Equipped with a first concave-convex pattern is formed on a side surface of the annular groove in a thickness direction perpendicular to the circumferential direction, a second concave-convex pattern is formed on a bottom surface of the annular groove in a radial direction perpendicular to the circumferential direction and the thickness direction, A grinding wheel characterized in that a third concave-convex portion having a depth smaller than that of the first concave-convex portion and the second concave-convex portion is formed on one or both of the side surface and bottom surface of the annular groove.

Images