JP2001179517A - Diamond drill and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a long diamond drill as a precision cutting tool used in the boring technique of minimum diameter, capable of forming a deep bore of minimum diameter of above 10 mm onto a hard material difficult in working such as a hard metal material, a silicon monocrystalline material and a ceramics material. SOLUTION: A diamond powder green compact is laminated on a green compact base material of a hard metal material, and treated under high temperature and high pressure to manufacture a hard metal integrally sintered- polycrystalline diamond board, and the board is cut in lattice as the cutting-out work of the material from the obtained integrally sintered-board in a state that the board is cut in the thickness direction with an arbitrary inclination angle of θ=30 deg.-85 deg. in the cutter inserting direction in one of the X.Y axial direction of at least the polycrystalline sintered-diamond board surface, whereby obtaining a long diamond drill shaped-blank having a pair of cutting faces opposite to each other and completing the top solid diamond drill by using this long rod-shaped worked blank material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a precision cutting tool used for a technology for drilling a hole having a very small diameter, and more particularly to a hard material such as a super hard material, a silicon single crystal material, and a ceramic material. The present invention relates to a top solid type diamond drill for drilling a very small diameter deep hole.

[0002]

2. Description of the Related Art Conventionally, a cutting tool for hard materials of this type includes, in metal working, a cutting surface of a drill base material made of a metal material having a general helical groove.
Titanium carbides / nitrides such as TiC and TiN, and DLC
When a hard film of (diamond-like carbon) is formed by a film forming method such as ion plating, or in the processing of glass / ceramics, diamond abrasive grains are electrodeposited on the surface of a metal material tool, or diamond abrasive grains are applied. (Hereinafter referred to as a diamond tool in which diamond abrasive grains are fixed to the surface of a metal tool) formed by baking the surface of a metal tool with a resin or the like to form a grindstone portion.

A common problem demanded of these various cutting tools is to firstly improve wear resistance, that is, extend the life cycle of the tip portion. The most typical one improved for that purpose is a “diamond drill” that can be used for various purposes without selecting the material of the workpiece.

In this method, a sintered body tip of polycrystalline diamond is attached to a cutting tool cutting edge of a drill base material made of a metal material and used in a drill shape. Due to the excellent properties such as hardness, wear resistance and thermal conductivity of polycrystalline sintered diamond, diamond drill using the polycrystalline sintered diamond as a cutting tool for drilling holes in silicon, carbon, ceramics, etc. Is attracting attention.

In general, the diamond drill is effective not only as a cutting tool for drilling holes in light alloys such as aluminum, but also for drilling holes in composite materials such as glass and epoxy resin and printed circuit boards. It has been specially developed for use in drilling difficult-to-machine materials such as cemented carbide, sapphire single crystal, and zirconia ceramics. “Top solid diamond drills” with tips are gradually being put into practical use and are currently being used.

[0006] More recently, with the demand for micromachining technology for ultra-precision parts that are indispensable for etching equipment used in semiconductor manufacturing processes, there has been a demand for a drill for drilling a very fine hole with higher precision, higher speed and longer life. And is being applied to difficult-to-machine materials such as silicon electrode plate parts of the etching apparatus.

However, at present, when a difficult-to-machine material such as a silicon electrode plate having a substrate thickness of 10 mm or more is used, the material is cut like a currently marketed top solid diamond drill with a shank shown in FIG. The drill length (L dimension of the effective portion for drilling) on the spindle tool side is short, and the length becomes insufficient, and the drilling dimension is limited.

In particular, in the case of a top solid diamond drill having a hole diameter of about φ0.30 mm to φ0.60 mm, in the manufacturing process of polycrystalline sintered diamond, from the current technical level of integral sintering with a cemented carbide base material, The L dimension of the drill length was limited to about 7 mm in length including the sintered diamond 81 and the base metal part 82.

[0009]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the diamond drill for drilling an ultra-fine deep hole and the problems of the prior art by forming a diamond powder compact on a cemented carbide compact. The body is laminated and processed under high temperature and high pressure to produce a cemented carbide integrated sintered type polycrystalline diamond substrate, and as a material removal from the formed integrated sintered substrate, the substrate is formed into a lattice shape. When cutting, at least one of the X and Y axis directions on the surface of the polycrystalline sintered diamond substrate is inclined obliquely in the thickness direction with an arbitrary inclination angle of θ = 30 ° to 85 ° in the cutting direction. In this way, a long and narrow rod-shaped diamond drill-formed blank in which a pair of opposing cut surfaces are parallel is obtained, and a long and long type top with a drill length (L dimension) of 7 mm or more is obtained using this long and narrow rod-shaped processed blank material. solid It is intended to produce a diamond drill.

At this time, when the substrate obtained in the process of producing polycrystalline diamond by integral sintering with a cemented carbide is cut into a lattice, the substrate is cut obliquely in the thickness direction with an angle of inclination in the direction of cutting. This ultimately determines the drill length (L dimension). That is, instead of simply cutting the sintered material substrate in a direction perpendicular to the substrate plane, at least one of the X and Y axis directions of the substrate surface is set as a cutting angle θ = 30 ° ~ 85
°, and the oblique cutting in the thickness direction is performed, and if the thickness of the substrate is t, the drill length (L dimension) is L = t / Cosθ. A blank can be obtained.

However, when the inclination angle is θ = 30 ° or less, the effect of the oblique cutting on the drill length (L dimension) can hardly be expected, and when θ = 85 ° or more,
It is not preferable because the material strength as a cutting tool of a very small diameter cemented carbide having a diameter of 0.3 mm may be insufficient.

By secondary processing of the above-mentioned drill compact blank, the external shape of the thin rod drill having polycrystalline sintered diamond at the tip is, for example, a pyramidal or multi-step tip angle at the tip of the drill. It has a substantially shell-shaped pyramid shape, and has an integrally sintered metal base material that is a polygonal prism having an elongated triangular prism or more, and as another example, has a spiral groove and land, and a twist angle. In the shape of a drill with a cylindrical side groove, the tip of which has a sintered diamond tip processed into a straight or undercut type shape or the like with a tip edge having a tip angle, or a spiral as another example. Sintered diamond processed into a drill shape with a groove, a land, and a cylindrical groove having a torsion angle, and a cone-shaped or substantially shell-shaped cone with a multi-step tip angle. Such as those having a-up to the tip, these elongated long type of top solid diamond drill can be easily manufactured.

Further, instead of the polycrystalline sintered diamond material, a polycrystalline cubic boron nitride (PCBN sintered body) is used as a hard material integrally sintered with a cemented carbide, and a similar top solid Drills for drilling may be prepared, and combinations of base materials such as cemented carbide suitable for integral sintering may be changed without departing from the spirit of the present invention.

[0014]

Embodiment 1 An embodiment of the manufacturing process of the present invention will be described below with reference to the drawings. The disk-shaped one shown in FIG. 5 (a) is a polycrystalline sintered diamond substrate obtained by sintering a cemented carbide integrally, and a diamond powder pressure is placed on a compacted substrate of a cemented carbide material (WC). Stack the powder,
This is processed under high temperature and high pressure to obtain an integrated sintered material substrate 50. The size of the formed integrally sintered material substrate 50 is approximately φ60 mm in outer diameter, and approximately 7 mm thick in the thickness direction including the sintered diamond layer 51 and the cemented carbide layer 52.

Next, as shown in FIG. 5 (b), the integrated sintered material substrate 50 is finely cut into a lattice shape in order to remove the material of a fine rod-shaped drill. At this time, at least one of the X and Y axis directions on the surface of the polycrystalline sintered diamond substrate,
The thickness direction is cut obliquely with an arbitrary inclination angle θ of 30 ° to 85 °.

As a result, an elongated rod-shaped diamond drill which is divided into individual rods as shown in FIG. 3C and has a thin rod shape as shown in FIG. A molded blank 105 is obtained.

More specifically, as shown in FIG. 6, for example, when the thickness of the substrate is about t = 7 mm and the cutting inclination angle of the cutting is θ = 55 °, the drilled blank 10
The effective drill length (L dimension) as 6 is L = about 12 mm including the cutting loss. Similarly, if the inclination angle is θ = 70
°, L = approximately 20 mm, and it is possible to obtain a long-sized molded blank nearly three times the limit length of the conventional drill length (L dimension).

Next, an example of producing a square pillar type diamond drill using the elongated rod-shaped drill-formed blank will be described. First, the cut elongated bar-shaped drill-formed blank is ground and shaped into the shape of each side that becomes a square prism.
Polishing is performed, and the tip of the polycrystalline sintered diamond side is further processed into a substantially shell shape having multiple tip angles shown in FIG.

By fixing this to the end of the cylindrical metal shank 5 by brazing, an elongated long size top solid diamond drill 20 having a drill length (L dimension) of about 20 mm having the external shape shown in FIG. 2 is completed. I do.

FIG. 1 is an enlarged perspective view of a tip portion of a blade of a diamond drill according to an embodiment of the present invention, wherein 1 is a polycrystalline sintered diamond portion, and 2 is a metal base of a main portion of a prismatic drill. The cemented carbide (tungsten carbide: WC) part used as the material, 3 is the boundary line of the joint formed by integral sintering, and 4 is the roughly bullet-shaped pyramid part with a multi-step tip angle that becomes the cutting edge of the drill tip FIG. 2 is a schematic perspective view of a completed diamond drill 20 in which the sintered body is brazed and fixed to five metal shank parts actually used for drilling.

The diamond drill 20 shown in FIG.
The finished product has L = approximately 20 when the drill length (L dimension) of the diamond drill main shaft part 10 is set to θ = 70 °.
mm, and drilling a hole using this diamond drill 20 makes it possible to drill a deep hole twice or more the limit length of the conventional drill length (L dimension).

[0022]

[Embodiment 2] Next, a process for producing a diamond drill having a different external shape by using an elongated rod-shaped diamond drill-formed blank obtained by a substrate cutting process similar to that of the embodiment 1 will be described. Here, the description of the contents relating to the manufacture of the substrate is omitted, but as shown in FIG. 7, as shown in FIG. 7, the cutting blade inclination angle is set to θ = 75 °, and the effective drill length as the drill forming base material is set to L = A molded blank 107 having a size of about 25 mm is obtained by cutting.

An example of manufacturing a diamond drill having a spiral groove using the elongated rod-shaped drill forming blank 107 will be described below. First, the cut elongated rod-shaped drill-formed blank 107 is formed into a cylindrical shape by grinding / polishing or electric discharge machining so that each diagonal portion becomes a perfect circular column, and further, the tip portion of the polycrystalline sintered diamond is formed. Is machined into a drill shape with a spiral groove to produce a diamond drill main shaft portion 30 shown in FIG.

As a result, the external shape of the thin rod drill having the polycrystalline sintered diamond at the tip is, as shown in FIG. 3, a spiral groove 34 and a land 35, and a helix angle of the spiral. The polycrystalline sintered diamond 31 at the tip of the cutting edge can have a tip cutting edge shape processed into a straight or undercut type shape having a tip angle.

By fixing this to the end of the cylindrical metal shank by brazing, it is possible to form a top solid with a spiral groove of a slender super long type having a drill length (L dimension) of 20 mm or more in the external shape shown in FIG. The diamond drill 40 is completed.

FIG. 3 shown here is an enlarged hexahedral view of the tip of the blade of a diamond drill according to another embodiment of the present invention, wherein 31 is a polycrystalline sintered diamond portion, and 32 is a main portion of a cylindrical drill. The cemented carbide (tungsten carbide: WC) part that becomes the metal base of the material, 33 is the boundary of the joint by sintering, and 36 is the straight or undercut type shape with the tip angle to be the tip of the drill FIG. 4 is a schematic side view of a finished product of a top solid diamond drill 40 in which the main shaft portion 30 of the sintered body is brazed and fixed to five metal shank parts actually used for processing. FIG.

Drilling using the actually completed diamond drill 40 having a diameter of 0.3 mm is performed by attaching the metal shank 5 shown in FIG. 4 to the collet chuck pedestal on the rotary shaft of the drilling machine. The centering position of the rotation center on the processing machine side is adjusted, and a silicon single crystal (10
0) Approx. 2000 in the center of the board, 100mm square x 16.0mm thick
The drilling of individual pieces was repeated continuously and evaluated.

An actual measurement evaluation test was performed on the silicon single crystal substrate on which the drilling process was completed.
As a result of measuring the diameter of each of the 1000th processed holes, the 100th, 200th, 300th, ‥
孔, 900th, 1000th hole diameter change at every 100th interval,
The diameter tolerance was within a set value range of ± 1 μm or less, and there was no significant change in the hole diameter and shape from the 1000th to 2000th holes, and the hole state was stable until the end.
At the same time, there was no significant change in the shape and diameter of the drill tip at the tip of the diamond drill, and stable drilling performance was maintained until the end.

[0029]

As described above, in the method of manufacturing a monolithically sintered diamond drill according to the present invention (claim 6), a diamond powder compact is formed on a cemented carbide base material. Are laminated and processed under high temperature and high pressure to produce a cemented carbide integrated sintered type polycrystalline diamond substrate,
When cutting the substrate into a lattice shape as a material removal from the formed integrally sintered substrate, at least one of the X and Y axis directions on the surface of the polycrystalline sintered diamond substrate, θ = By obliquely cutting in the thickness direction with an arbitrary inclination angle of 30 ° to 85 °, an elongated rod-shaped diamond drill forming blank in which a pair of opposed cut surfaces is parallel is obtained, and the elongated rod-shaped forming is performed. By forming the external shape of a diamond drill using a blank material, it is possible to obtain an unprecedented long size top solid diamond drill having a drill length (L dimension) of 10 mm or more.

In the diamond drill according to the present invention (claim 1), in the top solid diamond drill formed by sintering a cemented carbide in which a polycrystalline sintered diamond is arranged at the tip of a cutting drill, the polycrystalline sintered diamond is used. The diamond chip part of the above is a one-piece sintered metal base material separated from the drill tip by the cutting surface in the downward direction of the drill neck (the other direction of the center axis of the drill diameter) and at an angle to the center axis. A long size diamond drill can be provided in which an oblique region is disposed at an intermediate portion of a drill length extending from the tip of the drill to the above-mentioned joining surface in a direction below the neck with the joining surface as a boundary.

Further, in the diamond drill of the present invention (claim 2), the external shape of the thin rod drill having polycrystalline sintered diamond at the tip is substantially a pyramid or a multi-stage tip angle at the tip of the drill. It is possible to provide a long-sized diamond drill having a shell-shaped pyramid shape and an integrally sintered metal base material being a polygonal prism having an elongated triangular prism or more.

In the diamond drill of the present invention (claim 3), the external shape of the thin rod drill having polycrystalline sintered diamond at the tip is a spiral groove and a land, and a cylindrical groove having a twist angle. It is possible to provide a long-sized diamond drill having, at its tip, a sintered diamond tip processed into a straight or undercut type shape or the like having the same drill shape and a tip edge having a tip angle.

In the diamond drill of the present invention (claim 4), the external shape of the thin rod drill having polycrystalline sintered diamond at the tip is a spiral groove and a land, and a cylindrical groove having a twist angle. It is possible to provide a long-sized diamond drill having, at its tip, a sintered diamond tip that has a drilled shape and a tip of which is formed into a conical shape or a substantially shell-shaped conical shape having a multi-stepped tip angle. .

The present invention is also directed to a precision cutting tool dedicated to the above-described ultra-small hole drilling technique, which is used for hard-to-machine hard materials such as cemented carbide materials, silicon single crystal materials, and ceramic materials. It is possible to provide an elongated long size diamond drill for deep hole drilling, and realize a top solid diamond drill excellent in cost performance and wear resistance.

[Brief description of the drawings]

FIG. 1 is an enlarged perspective view of a tip portion showing an example of a diamond drill according to the present invention.

FIG. 2 is a schematic external view showing an example of a usage form of a diamond drill according to the present invention.

FIG. 3 is an enlarged hexahedral view of a tip portion showing another example of the diamond drill according to the present invention.

FIG. 4 is a schematic external view showing another example of a use form of the diamond drill according to the present invention.

FIG. 5 is a schematic view illustrating a part of the manufacturing process of the diamond drill according to the present invention.

FIG. 6 is a schematic view illustrating a cutting step in the production of a diamond drill according to the present invention.

FIG. 7 is a schematic diagram illustrating a cutting step in the production of a diamond drill according to the present invention.

FIG. 8 is a side view showing an example of a conventional top solid diamond drill having a spiral groove shape.

[Explanation of symbols]

 1, 31, 51, 81 Sintered polycrystalline diamond 2, 32, 52, 82 Cemented carbide 3, 33, 53, 83 Boundary boundary 4, 36 Cutting edge 5 Shank 34 Groove 35 Land 105, 106, 107 Drill forming blank

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[Procedure amendment]

[Submission date] February 9, 2001 (2001.2.9)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction contents]

By secondary processing of the above-mentioned drill compact blank, the external shape of the thin rod drill having polycrystalline sintered diamond at the tip is, for example, a pyramidal or multi-step tip angle at the tip of the drill. It has a substantially shell-shaped pyramid shape, and has an integrally sintered metal base material that is a polygonal prism having an elongated triangular prism or more, and as another example, has a spiral groove and land, and a twist angle. In the shape of a drill with a cylindrical side groove, the tip of which has a sintered diamond tip processed into a straight or undercut type shape or the like with a tip edge having a tip angle, or a spiral as another example. groove and the land portion, and the sintered drill shape cylindrical groove having a twist angle, and the tip edge portion is pyramid also <br/> is processed into a substantially bullet-shaped pyramid which gave the tip angle of the multi-stage Diamond Such as those having a Ndochippu the tip,
These elongated long type top solid diamond drills can be easily manufactured.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction contents]

In the diamond drill of the present invention (claim 4), the external shape of the thin rod drill having polycrystalline sintered diamond at the tip is a spiral groove and a land, and a cylindrical groove having a twist angle. It is possible to provide a long-sized diamond drill having, at its tip, a sintered diamond tip that has a drill shape and a tip edge portion is processed into a pyramid shape or a substantially shell-shaped pyramid shape having a multi-step tip angle. .

Claims (6)

[Claims] In a top solid diamond drill made of sintered cemented carbide in which polycrystalline sintered diamond is arranged at the tip of a cutting drill, the diamond tip portion of the polycrystalline sintered diamond is moved from the tip of the drill to the neck of the drill. From the tip of the drill to the neck at the joint surface with the integral sintered metal substrate, which is separated in a downward direction (the other direction of the center axis of the drill diameter) and at an angle of inclination with respect to the center axis, A diamond drill, characterized in that an obliquely mixed region is disposed at an intermediate portion of a drill length extending over the joining surface in a downward direction. 2. The appearance of a thin rod-shaped drill having polycrystalline sintered diamond at the tip is a pyramid or a substantially shell-shaped pyramid having a multi-stepped tip at the tip of the drill, and is integrally sintered. The diamond drill according to claim 1, wherein the metal substrate is a polygonal prism having an elongated triangular prism or more. 3. A thin rod-shaped drill having a polycrystalline sintered diamond at its tip has a spiral groove portion and a land portion.
2. A sintered diamond chip having a drill shape having a cylindrical side groove having a torsion angle and a tip or cutting edge processed into a straight or undercut type shape having a tip angle. Diamond drill. 4. A fine rod-shaped drill having a polycrystalline sintered diamond at its tip has a spiral groove portion and a land portion.
And a sintered diamond chip having a drilled shape with a cylindrical side groove having a torsion angle, and a tip edge portion processed into a conical shape or a substantially shell-shaped conical shape having a multi-staged tip angle. The diamond drill according to claim 1, wherein 5. The diamond drill according to claim 1, wherein a sintered boron nitride is used instead of the polycrystalline sintered diamond material. 6. A diamond powder compact is laminated on a cemented carbide base material and processed at high temperature and high pressure to produce a cemented carbide integrated sintered polycrystalline diamond substrate. When the substrate is cut into a lattice shape as a material removal from the formed integrally sintered substrate, at least one of the X and Y axis directions of the surface of the polycrystalline sintered diamond substrate is inserted in the cutting direction. By obliquely cutting in the thickness direction while giving an arbitrary inclination angle of θ = 30 ° to 85 °, an elongated rod-shaped diamond drill-formed blank in which a pair of opposed cut surfaces are parallel to each other is obtained. 5. A method for producing a diamond drill, wherein the external shape of the top solid diamond drill according to claim 1 or claim 2, 3 or 4 is formed using a rod-shaped blank material.