Metal bond grindstone

Abstract

To maintain good sharpness by appropriately expressing self-sharpening action due to breakage or wear of a metal binder.SOLUTION: A metal bond grindstone 1 comprises an abrasive grain layer 3 in which a plurality of abrasive grains 6 and a plurality of pores 7 are dispersed in a metal binder 5. A porosity of the plurality of pores 7 in the abrasive grain layer 3 is 40% or more and 99% or less. Each of the plurality of pores 7 is spherically formed. The plurality of pores 7 have: a communication pore 71 in which two or more pores 7 are communicated with each other; an independent pore 72 which is not communicated with other pores 7; and a micropore 73 having a pore diameter of 2 μm or more and 10 μm or less.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a metal bonded grinding wheel in which a plurality of abrasive grains are dispersed in a metal bond material. [Background technology]

[0002] A conventional metal bonded grinding wheel is described in Patent Document 1. The metal bonded grinding wheel described in Patent Document 1 has a volume ratio of abrasive grains to metal binder of 55-65% abrasive grains and 35-45% metal binder, and contains interconnected pores with a volume ratio of 25-35% in the grinding wheel. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 10-277948 Summary of the Invention [Problem to be solved by the invention]

[0004] The metal bonded grinding wheel described in Patent Document 1 contains interconnected pores, which allows the grinding wheel to exhibit a self-sharpening effect due to fracture or wear. However, because the porosity of the interconnected pores is 25-35%, the promotion of fracture or wear of the grinding wheel is insufficient, making it difficult to maintain good sharpness.

[0005] Therefore, an object of the present invention is to provide a metal bonded grinding wheel capable of maintaining good sharpness by appropriately exerting the self-sharpening action due to the fracture or wear of the metal bond material. [Means for solving the problem]

[0006] The metal bonded grinding wheel according to the present invention has an abrasive layer in which a plurality of abrasive grains and a plurality of pores are dispersed in a metal bond material, and the porosity of the plurality of pores in the abrasive layer is 40% or more and 99% or less. In this metal bonded grinding wheel, since the porosity of the plurality of pores in the abrasive layer is 40% or more and 99% or less, the strength of the abrasive layer is ensured while the self-sharpening action due to the fracture or wear of the metal bond material can be appropriately expressed. Therefore, good sharpness can be maintained.

[0007] Each of the plurality of pores may be formed in a spherical shape. In this metal bond grinding wheel, by forming each of the plurality of pores in a spherical shape, it becomes easier to control the strength of the abrasive layer and the self-sharpening cycle for realizing the self-sharpening action of the abrasive layer.

[0008] The average sphericity of the plurality of pores may be 0.2 or more and 1.0 or less. In this metal bond grinding wheel, the average sphericity of the plurality of pores is 0.2 or more and 1.0 or less, which makes it easier to control the strength of the abrasive layer and the self-sharpening cycle for expressing the self-sharpening action of the abrasive layer.

[0009] The plurality of pores may include interconnected pores formed by two or more pores interconnected. In this metal bond grinding wheel, the interconnected pores formed by two or more pores interconnected improve the dischargeability of chips and suppress clogging of the pores by chips.

[0010] The interconnected pores may include two or more interconnected pores having a pore diameter of 10 μm or more and 2000 μm or less. In this metal bonded grinding wheel, the interconnected pores include two or more interconnected pores having a pore diameter of 10 μm or more and 2000 μm or less, thereby ensuring the strength of the abrasive layer, improving the discharge of chips, and shortening the self-sharpening cycle caused by the fracture or wear around the interconnected pores. This allows the grinding wheel to maintain a high level of sharpness.

[0011] The metal bond grindstone may further include a reinforcing portion provided in the communicating pores to reinforce the abrasive layer. In this metal bond grindstone, the reinforcing portion for reinforcing the abrasive layer is provided in the communicating pores, so that the strength of the abrasive layer, which is reduced by the communicating pores, can be improved.

[0012] The reinforcing portion may be filled in at least a part of the communicating pores so as to be connected to at least a part of the inner surface of the abrasive layer that forms the communicating pores. In this metal bond grinding wheel, by filling at least a part of the communicating pores with the reinforcing portion so as to be connected to at least a part of the inner surface of the abrasive layer that forms the communicating pores, excessive crushing or wear around the communicating pores can be suppressed.

[0013] The reinforcing portion may contain a resin. In this metal bonded grinding wheel, the reinforcing portion contains a resin, so that the reinforcing portion can be easily formed.

[0014] The plurality of pores may be independent pores that are not connected to other pores. By having independent pores that are not connected to other pores, the metal bond grinding wheel can appropriately exhibit the self-sharpening action due to the crushing of the metal bond material while suppressing the decrease in strength of the abrasive layer.

[0015] The average pore size of the independent pores may be 2 μm or more and 100 μm or less. In this metal bonded grinding wheel, the average pore size of the independent pores is 2 μm or more and 100 μm or less, so that the strength of the abrasive layer is ensured and the self-sharpening cycle caused by the fracture or wear around the independent pores can be shortened. This makes it possible to maintain a high level of sharpness.

[0016] The plurality of pores may be micropores having a pore size of 2 μm or more and 10 μm or less. In this metal bond grinding wheel, the plurality of pores have micropores having a pore size of 2 μm or more and 10 μm or less, which can promote micro-fracturing or wear of the metal bond material. This makes it easier to control the self-sharpening cycle for expressing the self-sharpening action of the abrasive layer.

[0017] The porosity of the micropores in the abrasive layer may be 0.01% or more and 10% or less. In this metal bond grinding wheel, the porosity of the micropores in the abrasive layer is 0.01% or more and 10% or less, so that the strength of the abrasive layer is ensured while micro-fracturing or abrasion of the metal bond material can be promoted. Effect of the Invention

[0018] According to the present invention, good sharpness can be maintained by appropriately exerting the self-sharpening action due to the fracture or wear of the metal binder. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1(a) is a plan view showing an example of a metal bonded grindstone of the present embodiment, and FIG. 1(b) is a front view of the metal bonded grindstone shown in FIG. 1(a). [Diagram 2] FIG. 2 is a schematic end view showing a part of the abrasive layer taken along line II-II in FIG. [Diagram 3] FIG. 3 is a schematic end view showing a part of an abrasive layer according to a modified example, and corresponds to FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding elements are designated by the same reference numerals, and duplicated description will be omitted.

[0021] 1 and 2, the metal bond grinding wheel 1 according to this embodiment includes, as an example, a base metal 2 and an abrasive grain layer 3 fixed to the base metal 2. This metal bond grinding wheel 1 is a wheel-type metal bond grinding wheel in which an annular abrasive grain layer 3 is formed on the periphery of the disk-shaped base metal 2. However, the shape, size, use, etc. of the metal bond grinding wheel 1 are not particularly limited. In addition, the metal bond grinding wheel 1 may not include the base metal 2 and may be composed of only the abrasive grain layer 3.

[0022] The abrasive layer 3 of the metal bond grindstone 1 is configured by dispersing a plurality of abrasive grains 6 and a plurality of pores 7 in a metal bond material 5 .

[0023] The metal binder 5 holds a plurality of abrasive grains 6 and is made of a metal material. Examples of the metal material that forms the metal binder 5 include metals such as Ti (titanium), Cr (chromium), Fe (iron), Co (cobalt), Ni (nickel), Cu (copper), Ag (silver), Sn (tin), and W (tungsten), or alloys that contain at least a portion of these metals. Examples of the alloy that can be used include a Cu-Ag-Ti alloy, a Cu-Sn-Ti alloy, a Ni-Cr alloy, and a Cu-Sn alloy.

[0024] For example, superabrasive grains such as diamond, CBN, etc. are used as the abrasive grains 6. For example, grains having any grain size between #325 and #30000 can be used as the abrasive grains 6. For example, a filler such as WA (white alundum) or GC (green carborundum) may be added to the abrasive grain layer 3.

[0025] The pores 7 are holes formed in the abrasive layer 3. That is, the abrasive layer 3 is porous due to the pores 7. Some of the pores 7 are located on the surface of the abrasive layer 3, and the remaining part of the pores 7 is located inside the abrasive layer 3. The porosity of the pores 7 in the abrasive layer 3 is 40% or more and 99% or less. The porosity of the pores 7 in the abrasive layer 3 can be selected so as to obtain a suitable self-regenerating cycle depending on the application or purpose. For example, the porosity may be 70% or more and 90% or less, or 40% or more and 60% or less. The porosity of the pores 7 in the abrasive layer 3 is the percentage of the ratio of the pores 7 in the abrasive layer 3 to the area of ​​the abrasive layer 3. The porosity of the pores 7 in the abrasive layer 3 can be, for example, the percentage of the ratio of the total area of ​​the pores 7 to the area of ​​the abrasive layer 3 in any cross section of the abrasive layer 3.

[0026] Each of the multiple pores 7 is formed in a spherical shape. In addition to a perfect sphere, the sphere may be an oblate sphere or a deformed sphere having irregularities. The average sphericity of the multiple pores 7 may be, for example, 0.2 to 1.0, 0.5 to 1.0, or 0.7 to 1.0. The sphericity of the pores 7 is, for example, the ratio of the minimum diameter to the maximum diameter. That is, the sphericity of a pore 7 having a maximum diameter of 200 μm and a minimum diameter of 100 μm is 0.5. The average sphericity of the multiple pores 7 may be, for example, the average of the sphericities of the multiple pores 7 exposed to any cross section of the abrasive layer 3. In this case, the pores 7 exposed to any cross section of the abrasive layer 3 are partially cut off by the cross section, so that the sphericity may be measured by, for example, interpolating the shape of the cut-off part from the shape of the remaining part. As the interpolation, various well-known methods can be adopted.

[0027] The plurality of pores 7 have a communicating pore 71 formed by communicating two or more pores 7. That is, the communicating pore 71 is composed of two or more pores 7 that are mutually communicating. The abrasive layer 3 has a plurality of communicating pores 71. The communicating pores 71 are formed, for example, by adjacent pores 7 partially overlapping each other. In this case, for example, the sphericity of each pore 7 constituting the communicating pore 71 may be measured by interpolating the shape of the portion overlapping the adjacent pores 7 from the shape of the portion not overlapping the adjacent pores 7 by using a circular arc. The number of pores 7 constituting the communicating pore 71 is not particularly limited. The communicating pores 71 may include pores 7 having a hole diameter that can obtain an appropriate self-healing cycle depending on the application or purpose. For example, the communicating pores 71 may include two or more pores 7 that are connected to each other and have a pore diameter of 10 μm or more and 2000 μm or less, may include two or more pores 7 that are connected to each other and have a pore diameter of 10 μm or more and 1000 μm or less, or may include two or more pores 7 that are connected to each other and have a pore diameter of 10 μm or more and 100 μm or less. The pore diameters of the two or more pores 7 that constitute the communicating pores 71 can be obtained, for example, by interpolating the shape of the portion of each pore 7 of the communicating pores 71 exposed in any cross section of the abrasive layer 3 that overlaps with adjacent pores 7 using an arc, and measuring the pore diameter of each pore 7. The pore diameter of each pore 7 can be, for example, the maximum diameter of the pore 7.

[0028] The plurality of pores 7 have independent pores 72 that are not connected to other pores 7. The independent pores 72 are each composed of one pore 7. The abrasive layer 3 has a plurality of independent pores 72. The average pore size of the independent pores 72 may be, for example, 2 μm or more and 100 μm or less, 2 μm or more and 50 μm or less, or 50 μm or more and 100 μm or less. The average pore size of the independent pores 72 can be obtained, for example, by measuring the pore size of each of the independent pores 72 exposed on any cross section of the abrasive layer 3 and calculating the average of these measurement results. In this case, the independent pores 72 exposed on any cross section of the abrasive layer 3 are partially cut off by the cross section, so that the pore size may be measured, for example, by interpolating the shape of the cut-off part from the shape of the remaining part. As the interpolation, various well-known methods can be adopted.

[0029] The multiple pores 7 include micropores 73. The micropores 73 are pores 7 with a pore diameter of 2 μm or more and 10 μm or less. The micropores 73 may be pores 7 with a pore diameter of 2 μm or more and 4 μm or less, or may be pores 7 with a pore diameter of 5 μm or more and 10 μm or less. The pore diameter of the micropores 73 may be, for example, the longest diameter of the micropores 73. The abrasive layer 3 includes multiple micropores 73. The micropores 73 may be some of the pores 7 constituting the communicating pores 71, or may be independent pores 72.

[0030] The porosity of the micropores 73 in the abrasive layer 3 may be, for example, 0.01% to 10%, 0.01% to 5%, or 5% to 10%. This porosity is the percentage of the area of ​​the micropores 73 in the abrasive layer 3. The porosity of the micropores 73 in the abrasive layer 3 may be, for example, the ratio of the total area of ​​the micropores 73 to the area of ​​the abrasive layer 3 in any cross section of the abrasive layer 3.

[0031] As described above, in the metal bond grinding wheel 1 according to this embodiment, the porosity of the pores 7 in the abrasive layer 3 is 40% or more, so that the self-sharpening action due to the fracture or wear of the metal bond 5 can be appropriately exhibited. On the other hand, the porosity of the pores 7 in the abrasive layer 3 is 99% or less, so that the strength of the abrasive layer 3 can be ensured. In other words, the porosity of the pores 7 in the abrasive layer 3 is 40% or more and 99% or less, so that the strength of the abrasive layer 3 can be ensured while the self-sharpening action due to the fracture or wear of the metal bond 5 can be appropriately exhibited. Therefore, good sharpness can be maintained. These effects are further enhanced by the porosity of the pores 7 in the abrasive layer 3 being 70% or more and 90% or less, or 40% or more and 60% or less.

[0032] Furthermore, in this metal-bonded grinding wheel 1, each of the multiple pores 7 is formed into a spherical shape, which makes it easier to control the strength of the abrasive layer 3 and the self-sharpening cycle for expressing the self-sharpening action of the abrasive layer 3.

[0033] Furthermore, in this metal bond grinding wheel 1, the average sphericity of the plurality of pores 7 is 0.2 or more and 1.0 or less, which makes it easier to control the strength of the abrasive layer 3 and the self-sharpening cycle for realizing the self-sharpening action of the abrasive layer 3. These effects are further enhanced by the average sphericity of the plurality of pores 7 being 0.5 or more and 1.0 or less, or 0.7 or more and 1.0 or less.

[0034] Furthermore, in this metal bonded grinding wheel 1, the multiple pores 7 have interconnected pores 71, which improves the discharge of chips and prevents the pores 7 from becoming clogged with chips.

[0035] In addition, in this metal bonded grinding wheel 1, the communicating pores 71 include two or more pores 7 that are connected to each other and have a pore diameter of 10 μm or more, thereby improving the discharge of chips and ensuring the strength of the abrasive layer 3. On the other hand, the communicating pores 71 include two or more pores 7 that are connected to each other and have a pore diameter of 2000 μm or less, thereby shortening the self-renewal cycle caused by fracture or wear around the communicating pores 71. In other words, the communicating pores 71 include two or more pores 7 that are connected to each other and have a pore diameter of 10 μm or more and 2000 μm or less, thereby ensuring the strength of the abrasive layer 3, improving the discharge of chips, and shortening the self-renewal cycle caused by fracture or wear around the communicating pores 71. This makes it possible to maintain high sharpness. These effects are further enhanced when the communicating pores 71 include two or more pores 7 that are communicated with each other and have a size of 10 μm or more and 1000 μm or less, or 10 μm or more and 100 μm or less.

[0036] Furthermore, this metal bonded grinding wheel 1 has independent pores 72 that are not connected to other pores 7, which prevents a decrease in the strength of the abrasive layer 3 while allowing the metal bonding material 5 to properly exhibit its spontaneous sharpening action due to crushing, etc.

[0037] In addition, in this metal bonded grinding wheel 1, the average pore size of the isolated pores 72 is 2 μm or more, so that the strength of the abrasive layer 3 can be ensured. On the other hand, the average pore size of the isolated pores 72 is 100 μm or less, so that the self-renewal cycle caused by the fracture or wear around the isolated pores 72 can be shortened. In other words, the average pore size of the isolated pores 72 is 2 μm or more and 100 μm or less, so that the strength of the abrasive layer 3 can be ensured and the self-renewal cycle caused by the fracture or wear around the isolated pores 72 can be shortened. This makes it possible to maintain high sharpness. These effects are further enhanced by the average pore size of the isolated pores 72 being 2 μm or more and 50 μm or less, or 50 μm or more and 100 μm or less.

[0038] Furthermore, in this metal bonded grinding wheel 1, the pores 7 have micropores 73 with a pore size of 2 μm or more and 10 μm or less, which can promote micro-fracturing or wear of the metal binder 5. This makes it easier to control the self-sharpening cycle for expressing the self-sharpening action of the abrasive layer 3. These effects are further enhanced by the pores 7 having micropores 73 with a pore size of 2 μm or more and 4 μm or less, or 5 μm or more and 10 μm or less.

[0039] Furthermore, in this metal bond grinding wheel 1, the porosity of the micropores 73 in the abrasive layer 3 is 0.01% or more, which can promote micro-fracture or wear of the metal binder 5. On the other hand, the porosity of the micropores 73 in the abrasive layer 3 is 10% or less, which can ensure the strength of the abrasive layer 3. In other words, the porosity of the micropores 73 in the abrasive layer 3 is 0.01% or more and 10% or less, which can promote micro-fracture or wear of the metal binder 5 while ensuring the strength of the abrasive layer 3. These effects are further enhanced by the porosity of the micropores 73 in the abrasive layer 3 being 0.01% or more and 5% or less, or 5% or more and 10% or less.

[0040] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0041] For example, as shown in Fig. 3, the metal bond grinding wheel may have a reinforcing portion 9 provided in the communicating pores 71 to reinforce the abrasive layer 3A. The material of the reinforcing portion 9 is not particularly limited, but the reinforcing portion 9 may include, for example, a resin such as a phenolic resin, an epoxy resin, or a liquid resin, a coating material to which an inorganic material or a metal powder is added, liquid glass, or plating. When the reinforcing portion 9 includes a resin, the reinforcing portion 9 can be easily formed. When the reinforcing portion 9 for reinforcing the abrasive layer 3A is provided in the communicating pores 71, the strength of the abrasive layer 3A, which is reduced by the communicating pores 71, can be improved.

[0042] The reinforcing parts 9 may, for example, fill at least some of the communicating holes 71 of the abrasive layer 3A so as to be connected to at least a part of the inner surface 31 of the abrasive layer 3A that forms the communicating holes 71. By filling at least some of the communicating holes 71 with the reinforcing parts 9 so as to be connected to at least a part of the inner surface 31, excessive crushing or wear around the communicating holes 71 can be suppressed. In the modified abrasive layer 3A shown in FIG. 3, as an example, the reinforcing parts 9 fill all of the communicating holes 71.

[0043] In addition, in the above embodiment, the multiple pores are described as having all of the communicating pores, the independent pores, and the fine pores, but the multiple pores do not have to have all of the communicating pores, the independent pores, and the fine pores, and may have only some of the communicating pores, the independent pores, and the fine pores. [Explanation of symbols]

[0044] 1...metal bonded grinding wheel, 2...base metal, 3...abrasive layer, 3A...abrasive layer, 5...metal bonding material, 6...abrasive grains, 7...pores, 9...reinforcement portion, 31...inner surface, 71...communicating pores, 72...independent pores, 73...micropores.

Claims

1. The material comprises a metal binder with a layer of abrasive grains and multiple spherical pores dispersed within it. The porosity of the plurality of spherical pores in the abrasive layer is 40% or more and 99% or less. The plurality of spherical pores have communicating pores formed by two or more of the spherical pores being connected to each other, in a metal bond grinding wheel.

2. The metal bond grinding wheel according to claim 1, wherein the porosity of the plurality of spherical pores is 70% or more.

3. The metal bond grinding wheel according to Claim 1, wherein the porosity of the plurality of spherical pores is 70% or more and 90% or less.

4. The metal bond grinding wheel according to any one of claims 1 to 3, further comprising a reinforcing portion provided in the communicating pores for reinforcing the abrasive grain layer.

5. The metal bond grinding wheel according to claim 4, wherein the reinforcing portion is filled in at least a portion of the communicating pores so as to be connected to at least a portion of the inner surface of the abrasive layer forming the communicating pores.

6. The aforementioned reinforcing part includes resin, Some of the aforementioned spherical pores are located inside the abrasive layer. The metal bond grinding wheel according to claim 4 or 5, wherein the plurality of spherical pores arranged inside the abrasive layer have the communicating pores reinforced by the filling of the resin.

7. The plurality of spherical pores have independent pores that are not connected to the communicating pores. A metal bond grinding wheel according to any one of claims 1 to 6.

8. The average pore size of the independent pores is between 2 μm and 100 μm. The metal bond grinding wheel according to claim 7.

9. The plurality of spherical pores have micropores with a pore diameter of 2 μm or more and 10 μm or less. A metal bond grinding wheel according to any one of claims 1 to 8.

10. The porosity of the micropores in the abrasive layer is 0.01% or more and 10% or less. The metal bond grinding wheel according to claim 9.

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