JPH02292174A - Super abrasive grain grindstone - Google Patents

Abstract

PURPOSE:To form a base metal with a titanium alloy without causing a crack and defective adherence on the joining face with a grindstone layer by joining a grindstone layer including super abrasive grains to a base metal made of titanium or titanium alloy. CONSTITUTION:A grindstone layer 2 having super abrasive grains like a diamond and CBN bonded thereto by a vitrified bond is directly joined on a base metal 1 made of a plate like titanium alloy an a desired super abrasive grain grindstone is obtained. A crack on the joining face of the base metal 1 and grindstone layer 2 and a defective adherence can thus be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a superabrasive grindstone used for precision machining such as grinding, cutting, and small work of various workpieces.

"Prior Art" A superabrasive grindstone using ultra-hard abrasive grains such as diamond or CBN is usually constructed by bonding a grindstone layer containing the superabrasive grains to a base metal. The grindstone layer consists of abrasive grains, a binder, and a filler. Among these, binders can be broadly classified into the following four types.
Various types are used and are appropriately selected depending on the abrasive grain and processing conditions. That is, resin bond made of a thermosetting organic binder mainly composed of phenolic resin, Cu, Sn. There are metal bonds made of alloys such as Ni, vitrified bonds made of inorganic binders such as glass and ceramics, and electrodeposition methods in which abrasive grains are electrodeposited by electroplating.

On the other hand, focusing on the base metal for bonding and holding the grindstone layers, for example, in the case of a flat grindstone, a resin base metal is often used.

In addition, in the case of grinding wheels and cutting blades, metal bases are often used, specifically Aj alloys and Fe-based alloys (ordinary steel or high alloy steels such as Ni-Co@ and stainless steel). In some cases, hardening materials such as WC and ceramic composite materials are also used. (For example, JP-A-58-22663, JP-A-58-181574)
No., JP-A-59-59352, JP-A-59-1105
(Refer to each publication No. 60) [Problems to be solved by the invention] By the way, when considering the properties required of the base metal of a super-abrasive grinding wheel, it is a prerequisite that the base metal can be integrally joined to the grinding wheel layer in close contact with it. The main points are that the grinding wheel layer can be held rigidly, that it is strong, and that it has high heat resistance and corrosion resistance.
Requirements include low specific weight, low coefficient of thermal expansion, high vibration absorption ability, and high cooling effect with grinding fluid. However, the base metals made of the above-mentioned materials used in current superabrasive grinding wheels have advantages and disadvantages due to manufacturing constraints, and can be broadly adapted to the various properties required of the grinding wheel. I can't find anything.

In view of these circumstances, the present invention aims to open a new frontier in the field of superabrasive grindstones by improving the base metal, and at the same time improve the performance of the grindstone as a whole.

[Means for Solving the Problems] The superabrasive grinding wheel newly proposed by the present invention is made by using the various bonding methods described above on a base metal made of titanium or titanium alloy (hereinafter simply referred to as titanium alloy). It is made by bonding grindstone layers containing super abrasive grains.

At that time, if the adhesion of the grinding wheel layer to the base metal is insufficient, the bonding surface of the titanium alloy base metal should be etched multiple times with oxuic acid or a mixed acid mainly composed of oxuic acid. You may use the one you have prepared.

Furthermore, for the purpose of bonding the grinding wheel layer to the base metal by metal bonding or electrodeposition, the bonding surface of the titanium alloy base metal is etched multiple times with oxuic acid or a mixed acid mainly composed of oxuic acid, and then copper It is possible to use a material that has been subjected to a surface treatment to form a film.

[Function] In this way, in the case of a superabrasive grindstone in which the grinding wheel layer is bonded to the base metal made of titanium alloy, the titanium alloy has a large specific strength compared to other metal materials, and is rich in heat resistance and corrosion resistance. In addition, it exhibits a number of properties that are advantageous in bonding and holding the grinding wheel layers, such as a small coefficient of thermal expansion and excellent vibration absorption ability, so by improving the characteristics of this base metal, various improvements and improvements can be made to the grinding wheel structure. Changes can be made, and at the same time, the performance of the grindstone as a whole can be improved.

In addition, if the adhesion of the grinding wheel layer to the titanium alloy base metal is insufficient, the problem of poor adhesion can be avoided by etching the joint surface of the base metal multiple times with oxuic acid, etc. It can be solved.

Furthermore, if a base treatment to form a copper film is performed in addition to the multiple etchings described above, it is possible to bond the grinding wheel layer to the titanium alloy base metal by metal bonding or electrodeposition, and the titanium alloy base metal The structure of super-abrasive grinding wheels using gold can be made more diverse.

[Example] Examples of the present invention will be described below for each type of grindstone.

This example shows a case where the present invention is applied to a flat plate-shaped super-abrasive grindstone used for hand-polishing grindstones and the like.

Figure 1 shows a cross section of a superabrasive grinding wheel, in which a grinding wheel layer 2 in which superabrasive grains such as diamond or CBN are bonded by vitrified bond is directly bonded onto a plate-shaped titanium alloy base metal 1. There is.

This grindstone can be shaped without cracking during firing.

That is, a vitrified bond grinding wheel layer 2, which is a mixture of superabrasive grains, bond, necessary fillers, etc. in a predetermined ratio, is applied to a titanium alloy base metal 1 in a layered manner, as shown in FIG.
It is manufactured by a process in which it is set in press molds 3 and 4, pressure-molded, dried, and then fired at a high temperature.

If a metal base such as Ap alloy or steel is used, there are many cases in which cracks and peeling occur in the whetstone layer during the above-mentioned firing stage. It is used by bonding it to gold.

However, when using the base metal 1 made of titanium alloy, if the grinding wheel layer 2 is bonded with a vitrified bond, the surface of the base metal 1 is chemically compatible with the components of the vitrified bond, and the titanium alloy base metal 1 is bonded with a vitrified bond. Due to the small coefficient of thermal expansion, the grinding wheel layer 2 does not crack or separate from the base metal 1 during the firing process, and the grinding wheel layer 2 is bonded to the titanium alloy base metal 1.
It can be bonded over a wide area with good adhesion.

In a flat superabrasive grindstone in which the base metal 1 is made of a titanium alloy, compared to a resin-based one, the grindstone layer 2 is formed on the base metal 1.
It is advantageous in that it can be integrally molded.

By the way, in the above example, the case where the grinding wheel layer 2 is bonded with triphite bond is explained, but if resin bond is used as the bonding agent, there is a problem of poor adhesion of the grinding wheel layer 2 to the base metal 1. is recognized. In such a case, an effective solution is to previously perform a surface treatment on the bonding surface of the titanium alloy base metal 1 by etching it multiple times with oxuic acid or a mixed acid containing oxuic acid as a main component.

That is, by performing this surface treatment, as the present inventor had already proposed in his previous application (Japanese Patent Application No. 63-304992), the bonding surface of the titanium alloy base metal 1 has a dense group of small holes. At the same time, a unique surface corrosion structure in which micropores are wrapped at the bottom of each small hole appears. When the bond material is applied to the activated surface, the small hole and the group of micropores are etched. A mechanical bonding effect can be obtained in which the bond material penetrates and is fitted into or anchored to the small hole and the group of small holes.

Therefore, if the grinding wheel layer 2 is bonded after performing such a ground treatment, good adhesion with the titanium alloy base metal 1 can be ensured even if the grinding wheel layer 2 uses resin bond as a binder. be able to. Therefore, for the grinding wheel layer 2 that is bonded to the titanium alloy base metal 1, the optimal bonding agent can be selected according to the abrasive grains and processing conditions, and a process of forming a copper film is added to the above-mentioned surface treatment. This makes it possible to use metal bonding and electrodeposition as described below.

Of course, even in the case of the vitrified bond grinding wheel layer mentioned first, the above-mentioned surface treatment can be applied, and in that case, the mechanical bond is superimposed on the chemical bond at the bonding surface, and the adhesion is further improved. It will be strengthened.

FIG. 2 shows a modified embodiment in which the base metal structure of the superabrasive grindstone shown in FIG. 1 is partially improved. That is, only the thick portion 1a on the side of the grindstone layer 2 is made of titanium alloy, and the remaining thick portion 1b is made of, for example, an alumite-treated A. The Q alloy is used to save the wall thickness of the relatively expensive titanium alloy. Note that an adhesive 5 may be appropriately interposed between the bonding surfaces of the two.

This example shows a case where the present invention is applied to a disc-shaped super-abrasive grindstone used for rotary grinding.

Figure 4 shows a cross section of a superabrasive grinding wheel, in which superabrasive grains such as diamond or CBN are bonded to the outer periphery of a disc-shaped titanium alloy base metal 6 with a shaft hole 8 in the center using a vitrified bond. The grindstone layer 7 is directly bonded.

In this grindstone, by filling and forming the grindstone layer 7 between the base metal 6 and the outer peripheral form, drying and firing, it is possible to join the grindstone layer 7 without cracking as in the flat type. Further, by performing the base treatment by etching multiple times, even if the grindstone layer 7 uses resin bond as a binder, it is possible to ensure adhesion and bond.

When applied to such a grinding wheel, a wheel made of a titanium alloy base metal 6 has remarkable advantages. In other words, this type of super-abrasive grinding wheel is used for ultra-precision processing such as NC processing and automatic sizing processing, but when the grinding wheel is heated by grinding heat or heat from the bearing, In terms of things,
Since the coefficient of thermal expansion is large, the outside diameter of the grinding wheel changes greatly, which causes a problem of large errors in machining accuracy. On the other hand, those using high-alloy steel have a high specific gravity, which induces vibrations in the grinding wheel, which is a factor that deteriorates machining accuracy.

However, when the base metal 6 made of titanium alloy is used, the coefficient of thermal expansion and specific gravity are small, while the specific strength and vibration absorption ability are large, so dimensional changes due to heat and vibration of the whetstone during rotation are suppressed. It is highly suitable for the purpose of ultra-precision machining.

FIG. 5 shows a modified embodiment in which the base metal 6 is combined by fitting an outer ring 6a made of titanium alloy to an inner ring 6b made of AfJ alloy.

FIG. 6 shows an improved embodiment in which the superabrasive grindstone shown in FIG. 4 is coated with an alumina spray coating 9 on both sides of its outer periphery.

In other words, shavings constantly collide with both sides of the base metal 6 near the grinding wheel layer 7 during grinding, and with the base metal 6 made of titanium alloy, which is somewhat lacking in wear resistance, this part (the edge of the cutting edge) is damaged early. Although there is a risk of wear, such a wear problem can be solved by coating with the alumina thermal spray coating 9.

In this case, both sides of the titanium alloy base metal 6 are also subjected to the above-mentioned surface treatment of etching with oxuic acid, etc., as described in detail in the specification of Japanese Patent Application No. 63-304992. , high adhesion of the sprayed coating 9 to the base metal 6 can be ensured.

FIG. 7 shows the superabrasive grinding wheel layer 7 shown in FIG.
An improved example is shown in which this is replaced with . That is, in this case, after the above-mentioned surface treatment is applied to the outer circumferential joint surface of the titanium alloy base metal 6, alumina abrasive grains 11 are first sprayed to an appropriate thickness, and then the abrasive grains 11 and A vitrified bond grindstone layer l2 of the same quality and good familiarity is bonded.

In this way, diamond and C are placed on the alumina abrasive grains 11.
In the case where the grinding wheel layers 12 containing super-abrasive grains such as BN are stacked, a material with a composition that has good adhesion to aluminum oxide can be reasonably selected as the grinding wheel layer 12, and the super-abrasive grains and the binder make the grinding wheel layer 12
can be made extremely hard. As a result, the service life of the grinding wheel layer 12 is extended, and the grinding wheel layer 1
2 can be formed into a highly rigid material with low elasticity as a whole, and high-precision machining with little distortion even after long-term use can be realized. On the other hand, since the binder can be imparted with appropriate brittleness, it can be expected to enhance the self-growth effect of the superabrasive grains and extend the dressing interval of the grindstone layer 12.

FIG. 8 shows a modified embodiment in which the grindstone layer l3 uses metal bond as a binder. In this case, the grinding wheel layer 13 is made of a copper coating wA that is well-fitted to the outer peripheral joint surface of the base metal 6 made of titanium alloy.
14 to ensure adhesion. As disclosed in Japanese Patent Application No. 63-304992, the copper film 14 is formed by etching with oxuic acid or the like several times, then applying copper halide to the surface, and performing a base treatment to thermally decompose the copper halide. , good adhesion to the base metal 6 made of titanium alloy is maintained.

This embodiment shows a case in which the present invention is applied to a superabrasive grindstone used as a cutting blade for an internally shaped vine.

Figures 9 and 10 show the plane of the grindstone and its inner circumferential cutting section 16.
It shows an enlarged cross section of the hollow base metal made of titanium alloy (
A grinding wheel layer 16 forming a cutting part at the inner circumferential end of the core base body 15
It is constructed by joining. In this case, since the grindstone layer 16 is required to have good sharpness, an electrodeposited grindstone is used. Therefore, the entire base metal 15 is first subjected to a base treatment to make the surface porous by etching multiple times with oxic acid, etc., and then a base treatment is added to form the copper film 17 only on the necessary inner peripheral edge by the above-mentioned process. . When the inner peripheral portion of the base metal 15 is eutectoid plated by immersing it in a Ni plating solution etc. in which diamond abrasive grains etc. are dispersed, the superabrasive grains 19 precipitated together with the plating metal 18 are electrolytically deposited only on the portion covered with the copper film 17. It will be worn.

The cutting blade with the grinding wheel layer 16 electrodeposited in this manner is suitable for precision machining for the same reason as mentioned in the example of the grinding wheel, based on the base metal 15 being formed of a titanium alloy. do. In addition, the problem is that the grinding fluid supplied to the grinding wheel layer (cutting part) is scattered in the rotational direction by centrifugal force and does not sufficiently penetrate into the cutting part, causing the cutting part to heat up and wear out, resulting in poor sharpness. The inner periphery type ivy is superior to the outer periphery type, but if the entire base metal 15 is etched multiple times to form a surface bolus as described above, the groups of small holes etched on the surface can be removed. This forms a so-called boget through which the grinding fluid permeates, thereby making it possible to further increase the cooling effect.

FIG. 11 shows an improved embodiment in which reinforcing means are added to the surface of the cutting blade shown in FIG. 10. That is, in this case, the surface of the titanium alloy base metal 15 that has been subjected to the surface treatment by etching a plurality of times is coated with the alumina spray coating 20 on the surface of the portion excluding the grinding wheel layer 16. In this way, wear in the vicinity of the grindstone layer 16 can be prevented, and the hard ceramic layer 20 is coated to increase the required rigidity of the base metal 15.

FIG. 12 shows an improved embodiment in which the holding of the superabrasive grains 19 in the grindstone layer 16 is also strengthened. That is, in this example, the superabrasive grains 19 are attached with their proximal ends partially embedded in the copper coating 17 formed on the inner peripheral end of the base metal 15, and the space between the superabrasive grains 19 is attached to the outside. A plating metal 18 such as Ni is plated so as to fill the area. The grinding wheel layer 16 having such a structure is obtained by mixing superabrasive grains 19 into a copper halide solution applied to the surface when performing a base treatment to form a copper film after etching the joint surface multiple times. , is produced by eutectoiding this with the copper film 17 and electroplating the plating metal 18 thereon. And this oval whetstone layer 1
In No. 6, the superabrasive grains 19 are deeply held in the outer plated metal 18 and the exposed height is reduced, so that the abrasive grain retention can be increased. At the same time, the outer plated metal 18 is preferentially deposited in the gaps between the electrically base superabrasive grains 19, so the grinding wheel layer 16
This eliminates the problem of locally amplifying the plating thickness at corners, etc., and as a result, the cut shape can be finished with high dimensional accuracy.

Incidentally, the above-mentioned embodiments are similarly applied to the case of a circumferentially shaped ivy.

This embodiment shows a case where the present invention is applied to a whetstone with a shaft used for small work processing.

FIG. 13 shows a cross-sectional structure of a whetstone with a shaft, in which an electrodeposited whetstone layer 25 in which superabrasive grains 23 are eutectoided with plated metal 24 via a copper coating 22 is placed on the outer peripheral tip of a shaft 21 made of titanium alloy. (Note that a metal bonded grindstone may be used instead of the electrodeposited grindstone).

If this is the case, the problem is that steel shafts lack rigidity and vibration damping ability, and carbide shafts such as WC lack adhesion to the grinding wheel layer. can be solved. In addition, if the ceramic spray coating 26 is formed adjacent to the grindstone layer 25 at the tip as in the embodiment, a composite grindstone having properties suitable for the processing area is provided.

[Effects of the Invention] As described above in detail in the Examples, the present invention prevents the occurrence of cracks or poor adhesion at the joint surface with the grinding wheel layer for various types of superabrasive grindstones used for processing such as grinding, cutting, and small work. Instead, the base metal could be made of titanium alloy. For products that use a titanium alloy base metal, bonding methods and electroplating can be performed by performing oxic acid etching multiple times as necessary, or by applying a base treatment to the bonding surface that forms a copper film after etching. Depending on the bonding method, it is possible to join various types of grinding wheel layers, and the combined structures and types of superabrasive grinding wheels can be diversified.In addition, it has many superior properties compared to other metal materials. The unique material properties of titanium alloys can improve the performance of grinding wheels in many ways.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a flat grindstone showing a first embodiment of the present invention, and FIG. 2 shows a modified embodiment thereof. FIG. 3 is a sectional view of a press form showing a method for manufacturing a flat grindstone. FIG. 4 is a sectional view of a grinding wheel showing a second embodiment of the present invention, and FIG. 5 is a sectional view showing a modified embodiment thereof. FIG. 6, FIG. 7, and FIG. 8 are sectional views showing an improved embodiment of the second embodiment, respectively. FIG. 9 is a plan view of a cutting blade showing a third embodiment of the present invention, and FIG. 10 is an A-A thereof.
It is an enlarged sectional view taken along the line. FIGS. 11 and 12 are sectional views having the same meaning as FIG. 10, respectively, showing an improved embodiment that is an improvement on the third embodiment. FIG. 13 is a sectional view of a titanium alloy shafted grindstone showing a fourth embodiment of the present invention. 1, 6, 15, 21... Titanium alloy base metal 2, 7, 1
2... Grindstone layer (vitrified bond) 13... Grindstone layer (metal bond) 16, 25... Grindstone layer (electrodeposited grindstone) 9, 26... Alumina spray coating 10... Composite grindstone 1. ... Alumina abrasive grains 14, 17, 22 ... Copper coating 18, 24 ... Plated metal 19, 23 ... Super abrasive grains

Claims (3)

[Claims] (1) A superabrasive grindstone characterized by having a grindstone layer containing superabrasive grains bonded to a base metal made of titanium or a titanium alloy. (2) A super grinding wheel layer containing super abrasive grains is bonded to the base treatment surface of a base made of titanium or titanium alloy that has been etched multiple times with oxuic acid or a mixed acid containing oxuic acid as a main component. Abrasive grindstone. (3) A grinding wheel layer containing superabrasive grains is bonded to the base treatment surface of a titanium or titanium alloy base that has been etched multiple times with oxuic acid or a mixed acid mainly composed of oxuic acid to form a copper film. Features of super abrasive grindstone.