JP2003011019A - Sintered super abrasive grain tip material and method of manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide tip material whose joining strength to tool base material is improved and an effective method of manufacturing it. SOLUTION: 1. Sintered super abrasive grain tip material comprises a sintered super abrasive grain layer comprising its super abrasive grains adjacent to each other joined to each other through a metal layer and/or a ceramic layer or directly and a steel material layer containing carbon of 0.90% or less integrated due to sintering. 2. Sintered super abrasive grain tip material is manufactured in such a way that mixture of super abrasive grain particles and metallic and/or ceramic binder, a cemented carbide alloy disk having the same outer diameter as the inner diameter of a cylindrical body made of metal of high melting point, and a disk made of steel containing carbon of 0.90% or less are layered in the cylindrical body in this order and sealed, and then, a sintered super abrasive grain layer is formed by sintering super abrasive grain particles with each other by putting it into a super high pressure and temperature process. At the same time, this sintered super abrasive grain layer, the cemented carbide alloy disk and steel disk are jointed to each other, and a layered structural body made of sintered super abrasive grains, cemented carbide alloy and steel is recovered from the super high pressure and temperature process.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to diamond and c.
-Sintered superabrasive grains formed by sintering superabrasive grains such as BN (cubic boron nitride), and structures such as chip materials, especially base materials
The present invention relates to a chip structure having improved strength of joining to (base metal) and withstanding an irregular impact load. The present invention also provides
It also relates to an effective method of manufacturing such a chip structure.

[0002]

2. Description of the Related Art A tip saw having a plurality of abrasive tips arranged on the circumference of a disc-shaped substrate (base metal) is used for cutting various composite materials and new materials. Conventionally, such a chip is constructed as a sintered superabrasive grain chip in which cemented carbide or so-called superabrasive grains such as diamond and c-BN are integrally sintered with a cemented carbide layer as a substrate. The chip is used by being joined to the base metal by a known method such as brazing.

As is well known, cemented carbide chips are relatively inexpensive, but they cannot always cope with the recent diversified new materials and composite materials. On the other hand, the joining of the sintered superabrasive grain tip to the steel base material is generally performed by brazing, but in this step, even if the superabrasive grains having high hardness themselves are used, the thermal effect during brazing is not affected. While receiving and deteriorating, there is a problem that this bonding strength is significantly reduced at high temperatures.
As a result, in the case of high-load machining, especially in the case of a hand saw with a large load fluctuation and a lot of dry work, the chips are likely to fall off the tool base material, and a sufficient tool life cannot be obtained.

[0004]

The present invention has been made to solve the above problems of the known art, and particularly, a chip material having an improved bonding strength to a tool base material and its effective effect. Its main purpose is to provide a manufacturing method.

[0005]

According to the present invention, firstly, the following chip material is provided. That is, the adjacent superabrasive particles have a metal phase and / or a ceramic phase,
Alternatively, a sintered superabrasive grain layer in which superabrasive grain particles are directly joined without passing through these phases and a steel material layer having a carbon content of 0.90% or less are integrally formed by sintering. Abrasive chip material.

According to the present invention, the following method is also provided as a typical and efficient method for producing the above sintered superabrasive grain tip material. That is, a mixture of superabrasive particles and a metallic and / or ceramic binder in a bottomed cylindrical body made of a high melting point metal, and a cemented carbide material having an outer diameter substantially the same as the inner diameter of the cylindrical body. After stacking and sealing the disk and the disk made of steel with a carbon content of 0.9% or less in this order, an ultra-high pressure and high temperature process,
That is, the superabrasive grains used such as diamond and c-BN are subjected to pressure and temperature conditions for a thermodynamically stable phase for several minutes for processing.

In this processing operation, sintering between the superabrasive particles progresses to form a sintered superabrasive layer, and at the same time, the sintered superabrasive layer, the cemented carbide disc, and the steel disc. Bonding between them also progresses. After the treatment is completed, the temperature and pressure are lowered, and the laminated structure made of sintered superabrasive grains, cemented carbide and steel is collected.

In the above-mentioned sintered superabrasive layer, the use of a metallic or ceramic binder slightly reduces the hardness of the sintered superabrasive layer, but in this case the liquid phase is supplied in the sintering process. As a result, the bonding of the entire chip material having the laminated structure can be made more reliable, so that an appropriate type and mixing amount are determined and mixed.

As the ceramic binder, a mixed powder of tungsten carbide and cobalt is most suitable, but tungsten carbide is partially replaced by other carbides such as titanium carbide and tantalum carbide, and cobalt is partially replaced by nickel. It is possible to

On the other hand, as the metallic binder, simple metals such as cobalt and nickel, or alloys containing these metals as main components, in particular, nichrome, amber, etc., in which the melt phase wets the superabrasive grains well. Appropriate.

In the present invention, the outer layer portion used for joining with the base metal in the chip structure is made of steel so that it can be welded to various steel materials constituting the base metal. As a steel grade, carbon content is 0.90% or less, preferably 0.40
Use the following: Especially chrome / molybdenum steel,
Austenitic or martensitic stainless steels are effective. Typically S in JIS (Japanese Industrial Standard)
Mention may be made of US 304 and 410 species.

By adopting such a constitution, the chip structure of the present invention can be firmly bonded to the steel base metal by various known welding or welding methods such as TIG, MIG, laser, beam welding. .

In either structure, the sintered superabrasive grain layer is welded to the steel layer as a whole. In this case, the sintered superabrasive grain layer and the steel material can be directly adjacent to each other, but between the two layers, a cemented carbide layer and / or a refractory metal such as titanium, tantalum, molybdenum or the like is a main component. If an intermediate layer made of a high melting point alloy is interposed, it is effective for preventing peeling due to relaxation of residual stress. The high melting point refers to a melting point of 1400 ° C. or higher in the present invention.

The refractory metals and alloys described above are more effective in stress relaxation if they are used as an intermediate layer and mixed in advance with the superabrasive grains as powder.

In the above-mentioned ultra-high pressure and high temperature process, Japanese Patent Publication No.
In addition to the device described in the publication, various known devices can be used.

As an alternative to the above-mentioned ultra-high pressure and high temperature method,
A chemical oven or the like based on the combustion synthesis reaction can also be used for producing the sintered superabrasive chip material of the present invention. That is, during the combustion synthesis reaction, the superabrasive grains are subjected to thermodynamically metastable pressure and temperature conditions, but since the heating time is extremely short, the adverse effect on the superabrasive grains contained can be ignored, By appropriately selecting the reaction system, it can be used as a heat source for sintering.

In the present invention, the thickness of the cemented carbide, the refractory metal or the alloy layer depends on the constitution of the superabrasive grain layer, but is generally effective if it is about 0.5 mm or more. On the other hand, the thickness of the steel material layer can be set arbitrarily.

In the present invention, the laminated structure composed of the superabrasive grains and the steel material layer recovered from the ultrahigh pressure and high temperature step is cut into a predetermined shape by a known method such as wire cutting after a predetermined polishing step. Use chip material. If necessary, this material is further polished to be finished into chips, which are then fixed to, for example, the outer peripheral portion of the base metal using a technique such as laser welding.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be concretely described with reference to the attached explanatory drawings. FIG. 1 is a schematic diagram of a sample configuration for use in an ultrahigh pressure and high temperature process. 2 is a front view showing an example of a tip saw to which the tip of the present invention can be applied, and FIG. 3 is a detail of the tip welded to a base metal (see FIG. 2).
FIGS. 4 and 5 are schematic views showing a portion indicated as A ″), and FIGS. 4 and 5 are structural diagrams showing particularly a welded portion of a chip manufactured according to the present invention.

[0020]

Example 1 As shown in FIG. 1, 100 parts of diamond powder (manufactured by Tomei Diamond Industry Co., Ltd.) having a nominal value of 8-16 μm and WC were used in a metal tantalum capsule 1 having an inner diameter of 14.37 mm.
And 40 parts of a premixed powder of Co. Next, a hard metal (WC-8% Co) disk 3 with an outer diameter of 14.3 mm and a thickness of 1 mm, and a SUS 304 stainless steel disk 4 (outer diameter 14.3 mm, thickness)
1 mm) was placed in this order, and the end of the capsule was bent inward to close it. The sample composition prepared in this manner is used for the indirect heating method and is known as a uniaxial type ultra-high pressure high temperature apparatus (for example, Japanese Patent Publication No. 60-59).
(See Japanese Patent Publication No. 008), and loaded in a reaction chamber of 6 GPa and 1550 ° C. for 5 minutes.

After the temperature and pressure were lowered, the sample constituents were recovered, the reaction chamber constituent materials and the tantalum capsule material were removed, and then the surface was polished to obtain a chip material. Further, it was cut into 4 × 2 × 2.2 mm strips by wire cutting, and the back surface of stainless steel was polished to obtain chips.

8 pieces of such strip-shaped chips 5 are prepared and shown in FIG.
It welded to the tool steel base metal 6 of the type shown in FIG. As shown in FIG. 3, the sintered diamond layer 5a,
As described above, each chip 5 including the cemented carbide layer 5b and the stainless steel layer 5c has the surface of the stainless steel 5c welded to the base metal 6. The welded part 7 was observed with a microscope with a magnification of 30 times. As shown in Fig. 4, no delamination of the chip, heat damage or burn cracking of the base metal / chip boundary surface was observed at all, and the table was in a good adhesion state. It was firmly bonded to gold.

[0023]

Example 2 The same diamond powder and the same SUS410 type stainless steel disc (outer diameter 14.3 mm, thickness 1.5 mm) were placed in this order in a metal tantalum capsule of the same size as in Example 1 above, and the end of the capsule was inserted. The part was bent inward and closed. The sample composition thus prepared was subjected to ultrahigh pressure and high temperature conditions in the same manner as in Example 1 above.

Similar to Example 1, the collected sample composition was polished on the surface and then cut into strips of 4 × 2 × 2.2 mm by wire cutting, and the back surface of stainless steel was polished to form chips. did.

Eight strip-shaped chip materials were prepared and laser-welded to the tool steel chip saw base metal shown in FIG. These chips were also joined to the base metal in good adhesion as shown in the structure chart of FIG.

[0026]

The sintered superabrasive chip structure of the present invention is
In particular, since the bonding strength to the base material (base metal) is improved and the strength against irregular impact load is significantly improved, it is particularly suitable for use in a tool for manual work in which the load fluctuation range is large.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a sample configuration for use in an ultrahigh pressure and high temperature process.

FIG. 2 is a front view of a tip saw manufactured in an example.

FIG. 3 is a detailed schematic diagram of a welded chip (“A” in FIG. 2)
Part shown as).

FIG. 4 is a structural diagram of a welded portion of a chip manufactured in an example of the present invention.

FIG. 5 is a structural diagram of a welded portion of a chip manufactured in another example.

[Explanation of symbols]

1 tantalum capsule 2 A mixture of diamond, WC and Co 3 Cemented Carbide Disc 4 stainless steel disc 5 strip-shaped chips 6 Tool Steel Base Metal 7 Welded part

Claims (10)

[Claims] 1. Adjacent superabrasive particles are metallic phase and / or
Alternatively, a sintered superabrasive grain layer in which superabrasive grain particles are directly bonded to each other via a ceramic phase or without these phases, and a steel material layer having a carbon content of 0.90% or less directly or the above sintered A sintered superabrasive grain tip material, characterized by being integrally configured by sintering through an intermediate layer sandwiched between a superabrasive grain layer and a steel material layer. 2. The sintered superabrasive chip material according to claim 1, wherein the intermediate layer is a cemented carbide material. 3. The intermediate layer is made of one or a combination of titanium, tantalum, and molybdenum elemental metals, and a metal material containing any of these metal species as a main component and having a melting point of 1400 ° C. or higher. The sintered superabrasive chip material according to claim 1, which is present. 4. The sintered superabrasive chip material according to claim 1, wherein the carbon content of the steel material is 0.4% or less. 5. The sintered superabrasive grain tip material according to claim 1, wherein the steel material is an austenite or martensite (Cr or Ni-Cr) series stainless steel material type. 6. The sintered superabrasive chip material according to claim 2, wherein the cemented carbide material is mainly composed of tungsten carbide and cobalt. 7. The sintered superabrasive grain tip stock according to claim 1, wherein the superabrasive grains are selected from diamond and cubic boron nitride. 8. A mixture of superabrasive grains and a metallic and / or ceramic binder in a cylindrical body made of a refractory metal, and a cemented carbide having an outer diameter substantially the same as the inner diameter of the cylindrical body. Material discs and steel discs with a carbon content of 0.9% or less are stacked and sealed in this order, and then subjected to the ultrahigh pressure and high temperature process to sinter and burn the superabrasive grains. At the same time as forming the bonded superabrasive grain layer, the sintered superabrasive grain layer, the cemented carbide disc, and the steel disc are joined together. A method for manufacturing a sintered superabrasive grain chip material, comprising: collecting a laminated structure made of steel and a steel material. 9. The binder is at least one carbide selected from WC, TiC and TaC, and at least one selected from Co, Ni or an alloy containing them as a main component.
9. The method for producing a sintered superabrasive chip material according to claim 8, which contains a metal of a kind. 10. A cylindrical body made of a refractory metal and superabrasive particles,
The carbon content having an outer diameter substantially the same as the inner diameter of the cylindrical body is 0.9% or less, and the discs made of steel are stacked and sealed in this order, and then subjected to an ultrahigh pressure and high temperature step to produce superabrasive particles. At the same time as forming a sintered superabrasive grain layer by performing mutual sintering, this sintered superabrasive grain layer, the joining between the steel discs, sintered superabrasive grains from the above ultra high pressure and high temperature step, And a method of manufacturing a sintered superabrasive grain tip material, comprising recovering a laminated structure made of steel.