JP2001212769A - Super-abrasive grain wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve performance of a super-abrasive grain wheel used for grinding processing of optical glass, ceramics, crystal, magnetic material, semiconductor material, or the like, and a super-abrasive grain cutting wheel used for fine cutting and/or grooving of these work pieces. SOLUTION: A pore-less super-abrasive grain layer area group and superabrasive grain layer group having pores are formed in a super-abrasive grain layer with a predetermined pattern. The super-abrasion grain layer area group having pores exhibits a lower grade compared to the pore-less super abrasion grain layer area group and tends to be worn and is depressed to form an edgeless gentle step working as a tip pocket. Thus, an effect to improve sharpness can be expected just like a segmented wheel. Since the super-abrasive grain layer is continuous, this super-abrasive grain wheel is edgeless, not like the segment, and exhibits an improved performance without problems such as chipping of a work piece and roughness on the surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superabrasive wheel used for grinding optical glass, ceramics, quartz, magnetic materials, semiconductor materials, etc., and more particularly, to precision cutting and grooving of these workpieces. The present invention relates to a superabrasive cutting wheel used for machining.

[0002]

2. Description of the Related Art The base material of conventional superabrasive cutting wheels is mainly steel, for example, carbon tool steel, alloy tool steel, and high-speed steel. And as a binder,
Resin bond, copper, tin, mainly composed of thermosetting resin,
Metal bond mainly composed of an alloy such as iron, cobalt and nickel, vitrified bond mainly composed of an inorganic material such as glass, electrodeposition bond mainly composed of nickel deposited by electroplating and chemical plating, etc. are used. Have been. And as the super abrasive, diamond abrasive, C
BN abrasive grains are used.

[0003] A superabrasive cutting wheel is often used, for example, for cutting or grooving magnetic materials, optical glass and ceramics. When used to form grooves in ferrite blocks or neodymium magnets, which are the cores of magnetic heads, or as superabrasive cutting wheels used to cut and separate prisms from optical glass materials, the outer diameter is Those having a diameter of Φ50 mm to Φ300 mm, a thickness of a blade portion of 0.1 mm to 4.0 mm, and a diamond substrate adhered to the outer periphery of a steel substrate with a resin bond, a metal bond, and an electrodeposition bond are often used.

Means for improving the sharpness and cutting efficiency of these superabrasive cutting wheels include, for example, a method in which a segment of a superabrasive layer is soldered to a substrate (base) as disclosed in Japanese Patent Laid-Open Publication No. 61-27007. What is fixed by attaching is known. The segment is made by sintering a mixture of super abrasive grains and a binder such as metal bond by heating and pressing.
In some cases, a holding layer containing no superabrasive grains (also referred to as a base) is simultaneously sintered to be easily brazed. This method is extremely excellent in sharpness, sharply improves cutting efficiency, and has the greatest effect. However, since the edge of the segment collides with the workpiece, chipping often occurs. However, the heat generated during brazing causes distortion of the substrate and segments,
It is suitable for the production of superabrasive cutting wheels having a large blade thickness, and is not at all applicable to the production of thin blades. .

[0005] As another means, there has been known a method in which a plurality of cut grooves are formed in the thickness direction of a superabrasive layer, as disclosed in Japanese Patent Laid-Open Publication No. Sho 59-118375.
This method is excellent in sharpness and is effective in improving cutting efficiency, but is inferior in sharpness to the segment method described above. However, since the edge does not directly collide with the machined part, chipping is less likely to occur than in the segment method, and the cut surface has a feature that a good surface roughness can be obtained. However, in this method, it is difficult to form a superabrasive layer having a small blade thickness, and it is also extremely difficult to form a groove after forming the superabrasive layer. There was a disadvantage.

As another means, there is known an apparatus disclosed in Japanese Patent Laid-Open Publication No. Sho 62-48464 in which only the outer peripheral edge of a cutting edge portion is formed into a wavy shape in the circumferential direction. This method is also excellent in sharpness and provides good surface roughness, but it is not only difficult to process the substrate into a corrugated shape, but it is not possible to use a tempered high-hardness substrate material. There was a disadvantage that the material was limited. Furthermore, there are also disadvantages such as application of resin bond, metal bond, and vitrified bond is difficult, and the binder is limited to electrodeposition.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. That is, the performance of superabrasive wheels used for grinding optical glass, ceramics, quartz, magnetic materials, semiconductor materials, and the like, and the performance of superabrasive wheels used for precision cutting and grooving of these workpieces are further improved. It is in.

[0008]

The most significant feature of the present invention is that in a superabrasive wheel having a base and a superabrasive layer, the superabrasive layer has a predetermined pattern and is made of nonporous superabrasives. That is, it is formed of an abrasive layer region group and a porous superabrasive layer region group. Here, the predetermined pattern is
For example, as shown in FIG. 1, the superabrasive layer is divided into eight equal parts in the circumferential direction, and a porous superabrasive layer region and a nonporous superabrasive layer region are alternately formed. In addition, 4 in FIG.
Equal division and 16 equal divisions of (b) are shown, but the present invention is not limited to these. Porous superabrasive layer layer group has a lower degree of bonding than nonporous superabrasive layer layer group, so it is easy to wear, similar to a wheel that has a gentle step without edges as it is used and has a segment The effect of improving sharpness can be expected. Since the superabrasive layer is continuous, there is no edge as in the segment system or the like, and it exhibits excellent performance without problems such as chipping of the workpiece and rough surface. Of course, depending on the method of finishing the superabrasive wheel, it is also possible to depress the superabrasive layer region group having pores from the beginning to form a tip pocket. For example, when dressing using free abrasive grains or the like after truing is completed with a super-abrasive cutting wheel of 100 mm in outer diameter, 0.3 mm in thickness, diamond grain size # 325, and metal bond, the maximum step in the radial direction is 0.1 to 0.2mm,
It is also possible to set the maximum step in the thickness direction to 0.01 to 0.02 mm.

More specifically, the porous superabrasive layer region group contains pores having a porosity of 1 to 50% by volume. The porosity determines how much the bonding degree is reduced and softened compared to the non-porous superabrasive layer region group. If the value of the porosity is too small, a difference in the degree of bonding with the non-porous superabrasive layer region group does not occur, so that the above-mentioned effect cannot be obtained. In addition, if the value of the porosity is too large, the strength of the superabrasive layer region group of the porosity is insufficient, and there is a possibility that the porosity may be broken during the processing, so depending on the type of the workpiece, the processing conditions, etc. The optimal value has to be determined. In consideration of the above, the porosity is preferably determined in the range of 2 to 40% by volume, more preferably 2 to 30% by volume, to obtain a good result.

[0010] The binder for the superabrasive layer is a metal bond. Considering the characteristics of the bond powder, almost all metal bond powders can be applied by providing irregularities of optimal dimensions on the die punch. In addition, a resin bond or a vitrified bond can be applied. In this case, it is necessary to devise the mold in consideration of the moldability and fluidity of the bond, such as splitting the upper and lower punch dies.

The superabrasive grain wheel is a superabrasive grain cutting wheel. The present invention
It is effective for a cutting wheel having a superabrasive layer having a thickness of 2 mm or less, and particularly effective for a thin blade cutting wheel having a superabrasive layer having a thickness of 1 mm or less. As a measure to improve the sharpness of the superabrasive cutting wheel, a method of using a segment method, a method of putting a plurality of grooves on the side surface of the superabrasive layer, and a plurality of cut grooves in the thickness direction of the outer peripheral superabrasive layer of the substrate are used. A method of forming, a method of forming only the outer peripheral edge of the substrate into a wavy shape in the circumferential direction, and the like are conceivable.However, if these methods are adopted in the thin blade cutting wheel,
This is because not only does the cost increase, but also good surface roughness cannot be obtained.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in the section of Examples.

[0013]

(Example 1) Outer diameter 101 mm, inner diameter 93 m
A ring-shaped upper and lower punch material having a thickness of 10 mm and a thickness of 10 mm was prepared. Each of the end faces on one side is divided into eight at a central angle of 45 degrees,
Grind the divided end face at every other four places to obtain 0.1
An upper and lower punch was provided with a step of mm. The punch was set in a mold, filled with a mixture of diamond abrasive grains and metal bond powder, and hot-pressed at 600 ° C. to complete sintering. After taking out from the mold and dressing the outer periphery of the sintered product, both surfaces were lap-finished to complete the superabrasive cutting wheel of the present invention. The finished superabrasive cutting wheel has a size of Φ100-0.3T-3X-40H,
The specifications are SD # 325-concentration 50-bronze metal bond. The pattern of the superabrasive layer was the eight-piece type shown in FIG. 1, and the porosity of the porous portion was about 3% by volume.

(Example 2) Outer diameter 101 mm, inner diameter 93 m
A ring-shaped upper and lower punch material having a thickness of 10 mm and a thickness of 10 mm was prepared. Each of the end faces on one side is divided into eight at a central angle of 45 degrees,
Grind the divided end faces at every other four places to obtain 0.2
An upper and lower punch was provided with a step of mm. The punch was set in a mold, filled with a mixture of diamond abrasive grains and metal bond powder, and hot-pressed at 600 ° C. to complete sintering. After taking out of the mold and dressing the outer periphery of the sintered product, both surfaces were lap-finished to complete the superabrasive cutting wheel of the present invention. The finished superabrasive cutting wheel has a size of Φ100-0.3T-3X-40H,
The specification is SD # 325-concentration 50-bronze metal bond. The pattern of the superabrasive layer was the eight-piece type shown in FIG. 1, and the porosity of the porous portion was about 8% by volume. Hereinafter, the superabrasive cutting wheels of Examples 3 to 6 were manufactured in the same manner, and compared with the conventional example by a cutting test. As a conventional example, the one having the same size and the same specification as the example and having a continuous non-porous superabrasive layer was used.

The cutting test was performed by slicing a crystal. The details are shown in Table 1.

[0016]

[Table 1]

Tables 2 and 3 show the results of the cutting test. In the example, it was found that the grinding resistance (Fv) was reduced by 40% at the maximum, the chipping was equivalent, and the cutting accuracy was improved by 15 μm at the maximum as compared with the conventional example. Proven.

[0018]

[Table 2]

[0019]

[Table 3]

As described above in detail, in the superabrasive wheel of the present invention, the superabrasive layer region group of the porosity is slightly recessed to form a chip pocket, thereby reducing grinding resistance and discharging ability of chips. Contribute to the improvement of Furthermore, a continuous superabrasive layer without edges provides good surface roughness with very little chipping. In particular, when applied to a superabrasive cutting wheel used for precision cutting and grooving of optical glass, ceramics, quartz, magnetic materials, semiconductor materials, etc., a very large effect can be expected.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment.

FIG. 2 is a diagram showing another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base 2 Porous superabrasive grain layer area 3 Porous superabrasive grain layer area 4 Superabrasive grain layer

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3C063 AA02 AB03 BA02 BA21 BB02 BC02 BC09 BG07 EE01 EE02 EE16 EE23 EE31 FF30

Claims (4)

[Claims] 1. A superabrasive grain wheel having a base and a superabrasive grain layer, wherein the superabrasive grain layer has a predetermined pattern in a nonporous superabrasive grain layer region group and a porous superabrasive grain layer. And a grain layer region group. 2. A superabrasive wheel according to claim 1, wherein said superabrasive layer region group having pores contains pores having a porosity of 1 to 50% by volume. 3. The superabrasive wheel according to claim 1, wherein the binder of the superabrasive layer is a metal bond. 4. The superabrasive wheel according to claim 1, wherein the superabrasive wheel is a superabrasive cutting wheel.