JP2002066930A - Grinding wheel and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grinding wheel maintaining a sharpness of the grinding wheel and having a long life of the grinding wheel in the grinding wheel in which super-abrasive grain is brazed onto an outer periphery of base metal. SOLUTION: A diamond abrasive grain D at a first stage and a spacer S made of carbon are alternately and regularly disposed on an outer periphery of base metal 2 of the grinding wheel. A spacer S at a second stage is disposed on the diamond abrasive grain D at the first stage and a diamond abrasive grain D at a second stage is disposed on the spacer S at the first stage respectively. A spacer S at a third stage is disposed on the diamond abrasive grain D at the second stage and a diamond abrasive grain D at a third stage is disposed on the spacer S at the second stage respectively. These abrasive grains and the spacers are adhered to the base metal 2 by an active metal-including brazing material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a diamond abrasive,
The present invention relates to a grinding wheel using super-abrasives such as CBN abrasives, and particularly to a grinding wheel having an improved life of the grinding wheel and a method of manufacturing the same.

[0002]

2. Description of the Related Art A grindstone in which superabrasive grains such as diamond abrasive grains and CBN abrasive grains are fixed to a base metal by a brazing method is used for grinding and polishing. Such a grinding wheel is required to be excellent in sharpness, to be stable for a long time, and to have a long grinding wheel life. However, whether it be diamond abrasive grains or CBN abrasive grains,
The sharpness and the service life decrease with the progress of the grinding operation.

[0003] The main reasons for this are that the state of attachment of the abrasive grains to the base metal is unstable and the abrasive grains easily fall off, the chip pocket is small, and the wear of the binder layer is large. To improve these points, Japanese Patent Application Laid-Open
-118938 and JP-A-10-230465
There is a whetstone disclosed in Japanese Patent Publication No.

Japanese Patent Application Laid-Open No. Hei 10-118938 discloses that the metal binder of a grindstone in which superabrasive grains are protruded and fixed to the outer edge of a base metal by a metal binder is 一層 of the particle diameter of the fixed superabrasive grains.
A grindstone as a brazing material containing one or more hard particles of superabrasive grains, abrasive grains, and hard compounds having the following particle sizes is described.
According to this grindstone, it is said that the wear resistance of the metal bonding material made of brazing material is increased, and the grinding performance and life of the grindstone can be improved.

Japanese Patent Application Laid-Open No. Hei 10-230465 discloses a grindstone having a hard abrasive layer on the outer periphery of a base metal.
A grindstone is described in which hard abrasive layers are laminated in a plurality of layers, pores are formed between the hard abrasive layers, and the hard abrasive grains are mutually bonded with a small specific surface area. According to this whetstone, the frictional heat during cutting and grinding is reduced, the thermal wear of the abrasive grains and the bond friction are reduced, and the machinability and durability are improved.

[0006]

According to the grinding wheel disclosed in the above publication, the grinding wheel life can be improved to a certain extent. However, Japanese Patent Application Laid-Open No. 10-1189
No. 38, the grinding wheel has only one abrasive layer, so even if the brazing filler metal contains hard particles to improve the wear resistance of the binder layer, the service life can be improved if one abrasive layer is worn. Therefore, it cannot be expected that the life of the grinding wheel is prolonged.

The grindstone disclosed in Japanese Patent Application Laid-Open No. Hei 10-230465 is a grindstone in which abrasive grains are filled in a cutting edge portion and impregnated with an active metal braze to form a porous cutting edge layer. Is not uniform, and the sharpness and the abrasion speed become unstable.

The problem to be solved by the present invention is that super abrasive grains are laminated in a plurality of layers on the outer peripheral surface of a base metal, and in a brazed grinding wheel, the abrasive grains are uniform in the plane direction and the height direction of the abrasive layer. In order to maintain the sharpness of the grindstone and further extend the life of the grindstone.

[0009]

A grinding wheel according to the present invention is a grinding wheel in which superabrasive grains such as diamond and CBN are laminated in a plurality of layers on the outer peripheral surface of a base metal and brazed. The upper layer spacers are arranged on the lower layer abrasive grains in which spacers are regularly arranged alternately, and the upper layer abrasive grains are arranged on the lower layer spacers, and these abrasive grains and spacers are activated. It is characterized by being fixed to the base metal by a brazing filler metal.

In the grinding wheel of the present invention, the abrasive grains and the spacer group on the lower layer side and the upper layer side are arranged as described above, so that a plurality of layers are regularly formed in the surface direction and the height direction of the base metal outer peripheral surface. Are formed. Since the abrasive grains are arranged in a plurality of layers, the abrasive grains are changed once or twice or more, and the life of the grinding stone is remarkably improved.

The specific arrangement of the abrasive grains is, for example, when the number of stacked abrasive grains is three, the abrasive grains of the first layer and the spacers are alternately and regularly arranged, and the abrasive grains of the first layer are arranged. And a second layer of abrasive grains are respectively disposed on the first layer of spacers, and a third layer of abrasive grains are further disposed on the second layer of abrasive grains.
The third-layer spacer has a configuration in which the third-layer abrasive grains are respectively arranged on the second-layer spacer.

Here, by using carbon or graphite as the material of the spacer, a carbide in which carbon or graphite is chemically bonded to Ti or Cr which is an active metal in the brazing material is formed on the surface. The sticking force is increased, and carbon or graphite acts as a solid lubricant and does not hinder the replacement of abrasive grains.

[0013] The height of each spacer is 1/1 of the abrasive grain size.
It is desirable to make it 4 to 1 times. If the spacer height is smaller than 1/4 of the abrasive grain diameter, the number of abrasive grains existing on the surface of the abrasive grain layer at the time of changing becomes excessively large, and the sharpness is reduced. On the other hand, if the height of the spacer is larger than the particle diameter of the abrasive grains, there are many portions where the abrasive grains are not present on the surface at the time of switching, and the sharpness is reduced. Also, the height of the spacer should be 1/4 to 1/4 of the abrasive particle size.
By arbitrarily changing it within the range of 1 time, the arrangement interval of the abrasive grains in the height direction of the abrasive grain layer can be changed. The shape of the spacer is not particularly limited, but the surface in contact with the abrasive grains is desirably a smooth surface, and a flat cylindrical or prismatic shape is preferable.

The above-mentioned grinding wheel comprises a step of applying a paste in which a brazing filler metal containing an active metal and a binder are mixed to a portion of a base metal on which an abrasive layer is to be formed, and alternately providing first layer abrasive grains and spacers on the paste. A step of regularly applying a paste on the first layer of abrasive grains and spacers, and a second layer of the paste on the first layer of abrasive grains coated with the paste. The step of laminating the second layer of abrasive grains on the first layer of spacers and the step of additionally applying a paste to such an extent that the second layer of abrasive grains and the spacers are not buried; Manufacturing method, or, in the above manufacturing process, a step of applying a paste on the lower abrasive grains and the spacer in a dot-like manner, the upper spacer on the lower abrasive grains coated with the paste, Laminating the upper layer abrasive grains on the lower layer spacer, and It can be manufactured by the method abrasive grains and spacers of the upper side plus the step of adding applying a paste to the extent that not filled.

Although the upper limit of the number of layers of abrasive grains is not particularly limited, when the above-described manufacturing method is employed,
When the number of laminations increases, complicated steps increase and the manufacturing cost increases. Therefore, the upper limit of the number of laminations is practically about 10 layers, and at most 20 layers or less. For example, when the number of layers of the abrasive grains is three, a step of applying a paste in which a brazing filler metal containing an active metal and a binder are mixed on the abrasive grain layer forming portion of the base metal, and a step of applying a first layer of abrasive grains on the paste And a step of regularly arranging the spacers alternately; a step of applying a paste on the abrasive grains of the first layer and the spacers in a dot-like manner; and a step of applying a paste on the abrasive grains of the first layer to which the paste is applied. A step of laminating the second-layer spacers with the second-layer abrasive grains on the first-layer spacers, and additionally applying a paste to such an extent that the second-layer abrasive grains and the spacers are not buried. A step of laminating a third-layer spacer on the second-layer abrasive grains to which the paste is applied, and a third-layer abrasive grain on the second-layer spacer, and additionally applying the paste The manufacturing method includes steps.

[0016]

1 is a view showing a grinding wheel according to an embodiment of the present invention, in which (a) is a front view, (b) is a sectional view, and FIG. 2 is an arrangement of abrasive grains and spacers in an abrasive layer. (A) is a plan view and (b) is a cross-sectional structure diagram.

A grindstone 1 shown in FIG. 1 is a grindstone for surface grinding of a plastic lens, an aluminum alloy or the like, 2 is a base metal, and 3 is an abrasive layer. The base 2 is made of iron and the outer diameter is 100
mm and the thickness is 17 mm. The abrasive layer 3 is formed in an annular shape with a width of 1.5 mm on the outer peripheral surface of the base metal 2. The cross-sectional structure will be such that diamond abrasive particles D and spacers S are arranged in three layers as shown in FIG. The structure is fixed by the material W.

The diamond abrasive grains D are superabrasive grains having a grain size of # 40/50, and the spacers S are made of carbon having a compressive strength of 6 GPa and have an outer diameter of 0.5 mm and a thickness of 0.2 mm (about 1/1 of the abrasive grain diameter).
The cylindrical spacer and the brazing material W of 2) are Ti-Zr-Cu-based active metal-containing brazing materials. The manufacturing procedure of the whetstone 1 is as follows.

A paste in which an active metal-containing brazing material W and a binder (organic solvent) are mixed is applied to the portion of the base metal 2 where the abrasive layer is to be formed. Using a screen in which holes having a diameter of 0.5 mm are arranged in a grid pattern at 1.25 mm intervals, diamond abrasive grains D and spacers S of the first layer are alternately arranged in a staggered pattern on the paste. Apply the paste in a dot-like manner on the arranged diamond abrasive grains D and spacers S. A second-layer spacer S on the first-layer diamond abrasive grains D on which the paste is applied;
Second layer diamond abrasive grains D on the layer spacer S
Are laminated. -The paste is additionally applied to such an extent that the diamond abrasive grains D and the spacers S of the second layer are not buried. A third layer of diamond abrasive grains D and a spacer S in the same manner as the lamination of the second layer diamond abrasive grains D and spacers S;
And apply the paste additionally. In this state, a three-layer structure of diamond abrasive grains D and spacers S is formed as shown in FIG. Baking it at 950 ° C. for 1 hour in a non-oxidizing atmosphere, and fixing the diamond abrasive grains D and the spacer S to the base metal.

The grinding wheel 1 thus manufactured (invention product)
And a grindstone having an abrasive layer formed on the same base metal by the method described in JP-A-10-118938 (comparative product)
The aluminum alloy was subjected to a grinding test. In addition,
1 grit # 100 GC abrasive is used for the brazing filler metal of the comparative wheel.
0% by weight was added. [Test conditions] Grinding machine: Tool grinder Grinding wheel peripheral speed: 1200 m / min Material to be ground: High silicon aluminum (ADC-14) Cutting depth: 0.05 mm / pass Feeding speed: 1.0 m / min Grinding method: Wet

FIG. 3 shows the test results. The figure shows the sharpness (expressed in power consumption) and the life of the grinding wheel of the comparative product as 10%.
It shows the sharpness and the grinding wheel life of the invention product when it is set to 0. As can be seen from the figure, the invention product, in which the abrasive grains are uniformly arranged in three layers using spacers, has about the same sharpness and approximately 2.7 times the grinding wheel life as compared to the comparison product grinding wheel with a single layer configuration. are doing.

Although the above embodiment is an example in which the abrasive grains are arranged in three layers, the arrangement of the abrasive grains in the present invention is not limited to three layers, and the abrasive grains are arranged in two or four or more layers. It also includes the whetstone that has been used.

[0023]

According to the present invention, the following effects can be obtained.

(1) An upper spacer is arranged on a lower abrasive grain in which abrasive grains and spacers are alternately and regularly arranged;
By arranging the upper layer abrasive grains on the lower layer spacer, a plurality of layers of abrasive grains can be formed regularly in the surface direction and the height direction of the base metal outer peripheral surface. Because the change is performed once or more than once,
The life of the grinding wheel is significantly improved.

(2) By using carbon or graphite as the material of the spacer, carbon or graphite is formed on the surface of a carbide chemically bonded to the active metal in the brazing material, so that the bonding strength of the spacer by the brazing material is increased.

[Brief description of the drawings]

FIG. 1 is a view showing a grinding wheel in an embodiment of the present invention, wherein (a) is a front view and (b) is a cross-sectional view.

FIGS. 2A and 2B are schematic views showing the arrangement of abrasive grains and spacers in an abrasive grain layer, wherein FIG. 2A is a plan view and FIG.

FIG. 3 is a graph showing a grinding test result.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Whetstone 2 Base metal 3 Abrasive layer D Diamond abrasive grain S Spacer W Brazing material

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsuya Nonoshita Noritake Diamond Co., Ltd., 210, Takeshi, Tanushimaru-cho, Ukiha-gun, Fukuoka Prefecture F term (reference) 3C063 AA02 AB03 BA32 BA40 BB02 BB23 BC02 CC09

Claims (4)

[Claims] 1. A lower layer in which superabrasive grains such as diamond and CBN are laminated in a plurality of layers on the outer peripheral surface of a base metal and brazed, and the abrasive grains and spacers are arranged alternately and regularly. The upper-layer spacer is arranged on the upper-side abrasive grains, and the upper-layer abrasive grains are arranged on the lower-layer spacer.These abrasive grains and the spacer are fixed to the base metal by the brazing filler metal containing active metal. There is a grinding wheel. 2. The grinding wheel according to claim 1, wherein the material of the spacer is carbon or graphite. 3. The method for producing a grinding wheel according to claim 1, wherein a step of applying a paste in which an active metal-containing brazing filler metal and a binder are mixed is applied to an abrasive grain layer forming portion of the base metal. A step of regularly arranging the first-layer abrasive grains and the spacers alternately; a step of applying a paste on the first-layer abrasive grains and the spacers in a dot-like manner; and a first step of applying the paste. A second layer spacer is placed on the second layer of abrasive grains,
Manufacturing a grinding wheel including a step of laminating a second layer of abrasive grains on a first layer of spacers, and a step of additionally applying a paste to such an extent that the second layer of abrasive grains and the spacers are not buried. Method. 4. The method for producing a grinding wheel according to claim 3,
A step of applying paste in a dot-like manner on the lower layer abrasive grains and the spacer; and an upper layer spacer on the lower layer abrasive grains coated with the paste, and an upper layer abrasive on the lower layer spacer. A method for manufacturing a grinding wheel, comprising: a step of stacking grains; and a step of additionally applying a paste to such an extent that the upper abrasive grains and spacers are not buried.