JPH0632655A - Diamond sintered compact and its production - Google Patents

Abstract

PURPOSE:To easily obtain at a low cost the subject uniform, firm, high- performance and high-density diamond sintered compact by using coated diamond powder prepared by coating the individual particles diamond powder with a binder and/or a sintering auxiliary each in an arbitrary amount ranging from a slight to large amount. CONSTITUTION:The objective diamond sintered compact can be obtained by coating the individual particles of diamond powder with a binder and/or a sintering auxiliary through immersion process followed by, either directly (i.e., in a powdered form) or after press molding, sintering at elevated temperatures under an ultrahigh pressure of >=2000MPa.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high density sintered body containing diamond and a method for producing the same.

[0002]

2. Description of the Related Art Diamond has many excellent properties due to its strong covalent bond, but on the other hand, due to its covalent bond, its self-diffusion coefficient is very small, which makes it extremely difficult to burn. In addition, diamond is thermodynamically stable only under ultrahigh pressure, and at high temperatures, there is also a problem of phase transition to graphite if the pressure is insufficient. Without the addition of a binder, strong sintering cannot be achieved unless a very high temperature of about 2440 K and an ultrahigh pressure of about 8500 MPa are applied.
However, such sintering conditions are extremely severe and are unsuitable for industrially producing a high-density diamond sintered body. Therefore, in order to manufacture the high-density diamond sintered body, it is necessary to sinter under industrially applicable conditions, and for that purpose, the addition of a binder and / or a sintering aid is essential. .

When a binder and / or a sintering aid is added in powder form, it is extremely difficult to add it uniformly ideally, that is, evenly disperse it. Even if even dispersion is realized, the binder is added. Since the sintering aid is added in powder particle units, there is a limit to the meaning of uniformity. In particular, when the added amount is small, there is a portion in the sintered body where the binder and the sintering aid do not exist. In reality, in many cases, the diamond powder and the powder of the binder and / or the sintering aid are aggregated and exist in a lump in the sintered body, or unevenly distributed in the sintered body. To do. Therefore, the agglomerated portion of the diamond powder is locally unsintered as in the case where no binder or sintering additive is added.

Therefore, in order to manufacture a high-density and strongly-bonded diamond sintered body, it is necessary to surely distribute the binder and / or the sintering aid in each particle of the diamond powder. It is necessary to evenly distribute the particles on the surface of each diamond powder. For that purpose, it is desirable that the particles of the diamond powder be uniformly coated with the sintering aid.

Conventionally, the PVD method, the CVD method, and the like have been used as the coating method, but it has been difficult to add an arbitrary amount of a substance from a very small amount to a large amount. Furthermore, it was difficult to uniformly coat the surface of each particle of the diamond powder with the binder and / or the sintering aid. Moreover, these methods are expensive because they require large equipment. Therefore, although the obtained sintered body is expensive, the performance of the sintered body is not sufficiently satisfactory.

[0006]

An object of the present invention is to uniformly coat a surface of each particle of diamond powder with a binder and / or a sintering aid in an arbitrary amount from a trace amount to a large amount. The present invention provides a high-performance, high-density, high-density diamond sintered body that is uniformly, densely, and strongly sintered with a coated diamond powder obtained by the method, and is simple and inexpensive. It is provided by means.

[0007]

Means for Solving the Problems The dipping method is a method previously proposed as a method for improving hardness and wear resistance as a surface treatment technique for metal materials (see Japanese Patent Publication No. 61-87873). After that, a method invented as a method for coating the abrasive grains for the grinding wheel to prevent oxidation of the abrasive grains for the grinding wheel and to prevent clogging of the grinding wheel during the grinding process (JP-A-1-
No. 207380, JP-A-1-234168), but as a result of intensive studies, by applying the dipping method as a binder and / or a sintering additive addition method, the binder and / or A method for producing a characteristic high-density diamond sintered body having a uniform and fine microstructure in which the distribution of the sintering aid is controlled was found, and the distribution of the binder and / or the sintering aid was controlled. Moreover, a high-performance high-density diamond sintered body having a uniform and dense microstructure and being strongly sintered was obtained.

In the present invention, the substance that coats the surface of the diamond powder is a so-called sintering aid that promotes the sintering of the diamond and / or the diamond sintered body.
It goes without saying that it is composed of a binder that firmly bonds the diamond particles.

That is, basically, in the method for producing a diamond sintered body of the present invention, a coating film of a substance consisting of a binder and / or a sintering aid, which is derived from the dipping method, is formed on the surface of diamond powder. Ultra high pressure of 2000MPa or more
It is characterized by being sintered at a high temperature.

Alternatively, a coated diamond powder having a coating film of a substance, which is derived from the dipping method and is composed of a binder and / or a sintering aid, is provided on the surface of the diamond powder in an amount of 1% by volume.
An ultra-high powder of 2000 MPa or more is obtained by powder-mixing a mixed powder made by mixing 99% to 0.1% by volume of a powder of 99.9% with the balance being metal or a compound, and then pressing. Coated diamond powder characterized by being sintered under pressure and high temperature, or provided with a coating film of a substance consisting of a binder and / or a sintering aid derived from an immersion method on the surface of the diamond powder The body is 1% to 99.9% by volume, the balance is
A mixed powder obtained by mixing 99% to 0.1% by volume of a coated powder in which a coating made of at least one kind of a metal or a compound is provided on the surface of a powder of a metal or a compound in a powder form, Alternatively, it is characterized by being sintered at an ultrahigh pressure of 2000 MPa or higher and at a high temperature after embossing, or a substance derived from an immersion method on the surface of a diamond powder, which is composed of a binder and / or a sintering aid. The coated diamond powder provided with the coating film of 50% to 99.9% by volume, the balance being a metal having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more. Alternatively, a fibrous substance composed of at least one kind of compound is added in an amount of 50% to 0.1% by volume.
It is characterized in that the mixture obtained by mixing the above is sintered at the same time or after embossing and molding under an ultrahigh pressure of 2000 MPa or higher and a high temperature.

Alternatively, a coated diamond powder having a coating film of a substance which is a binder and / or a sintering aid derived from the dipping method is provided on the surface of the diamond powder in an amount of 50% to 50% by volume.
99.9%, the balance being 500 μm or less in minor axis, and the ratio of the major axis to the minor axis is 2 or more on the surface of the fibrous substance made of at least one kind of metal or compound,
A mixture of 50% to 0.1% by volume of a coated fibrous material provided with a coating made of at least one kind of metal or compound is used at the same time or after embossing to obtain a mixture of 2000 MPa or more. Characterized by sintering under ultra high pressure and high temperature, or on the diamond powder surface,
The coated diamond powder, which is derived from the dipping method and is provided with a coating film of a substance that serves as a binder and / or a sintering aid, has a volume of 1% to 99.9%, and the balance of 500 mm or less in minor axis ,
The volume ratio of the fibrous substance made of at least one kind of metal or compound and the powder of metal or compound in the ratio of the major axis to the minor axis of 2 or more is 0.1: 100 to 10 by volume.
The mixture of 0: 0.1 is mixed with 99% to 0.1% by volume, and the mixture is pulverized or is pressed and then sintered under ultrahigh pressure and high temperature of 2000 MPa or more. 1% to 99% by volume of coated diamond powder, which is characterized in that a coating film of a binder and / or a sintering aid derived from an immersion method is provided on the surface of the diamond powder. .9%, the balance being a fibrous substance made of at least one kind of metal or compound having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more, and a powder of the metal or the compound. A mixture having a coating powder of at least one kind of metal or compound on the surface thereof in a volume ratio of 0.1: 100 to 100: 0.1 is added in an amount of 99% to 0.1%. Mix the resulting mixture in powder form, After stamping molding, 2000MPa
Characterized by being sintered under the ultra-high pressure and high temperature described above, or by coating the surface of diamond powder with a coating film of a substance that is a binder and / or a sintering aid derived from an immersion method. The coated diamond powder has a volume of 1% to 99.9%, and the balance is at least one kind of metal or compound having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more. The ratio of the coated fibrous substance to the powder of the metal or compound is 0.1: 10 by volume, in which the surface of the fibrous substance is coated with at least one kind of metal or compound.
The mixture consisting of 0-100: 0.1 is 99% by volume.
A mixture obtained by mixing 0.1% is characterized in that it is powdered, or after stamping and molding, it is sintered under ultrahigh pressure and high temperature of 2000 MPa or more, or on the diamond powder surface, The coated diamond powder, which is derived from the dipping method and is provided with a coating film of a substance that serves as a binder and / or a sintering aid, has a volume of 1% to 99.9%, and the balance is 500 μm or less in minor axis. A coated fibrous substance comprising a fibrous substance made of at least one kind of metal or compound in a shape in which the ratio of the major axis to the minor axis is 2 or more, and a coating made of at least one kind of metal or compound is provided on the surface of the fibrous substance. ,
A mixture comprising a powder of a metal or a compound, the surface of which is provided with a coating of at least one kind of a metal or a compound, and the ratio of the coated powder is 0.1: 100 to 100: 0.1 by volume,
A mixture formed by mixing 99% to 0.1% by volume,
It is characterized in that it is sintered in a powder form or after embossing at an ultrahigh pressure of 2000 MPa or higher and a high temperature.

The above is more preferably sintered in the thermodynamically stable region of diamond and under ultrahigh pressure and high temperature of 2000 MPa or more.

Further, the diamond sintered body of the present invention is a diamond sintered body characterized by being sintered by the above-mentioned method, and the surface of each particle of the raw material diamond powder is subjected to the dipping method. By sintering the particles of the coated diamond powder obtained by uniformly providing a coating film made of a substance consisting of a binder and / or a sintering aid, which is derived from the diamond, Except where the particles are directly contacted and bonded, the binder and / or the sintering aid is always present, and the binder and / or the binder is present on at least a part of the particle surface of the diamond in the diamond sintered body. And / or a high-performance, high-density diamond sintered body in which a sintering aid is present in contact, is uniformly, densely, and strongly sintered.

[0014]

Description of Means The means for solving the problems will be described in more detail below.

Here, the dipping method in the present invention is generally a method in which the diamond powder is dipped in a molten salt bath to form a surface coating. In addition, the disproportionation reaction is also generally called an asymmetric change, and as a result of mutual oxidation, reduction or other reaction of two molecules or more of one type of substance,
To produce more than one type of substance.

The dipping method according to the present invention is, for example, a dipping method involving the above-mentioned disproportionation reaction, and a coating film of a substance derived from the dipping method which is a binder and / or a sintering aid is provided. The coated diamond powder is obtained by a method of forming a coating film of at least one kind of a target metal carbide, boride, nitride and silicide on the surface of the diamond powder by an immersion method. It is manufactured by preparing a molten salt bath containing a metal, and then immersing the diamond powder to be treated in the dipping bath for an appropriate period of time.

The molten salt bath comprises, for example, at least one kind of chloride of alkali metal and alkaline earth metal, and the fluoride comprises at least one kind of fluoride of alkali metal and alkaline earth metal. Or, alternatively,
The molten salt is a fluoride-containing molten oxalate bath, a fluoride-containing molten iodide bath or a fluoride-containing molten fluoride bath, which is an oxide, halide or elemental metal or a metal of the above-mentioned object. The immersion bath may be prepared by adding an alloy. In this case, the fluoride and oxalide or iodide may preferably be selected from the alkali metal and alkaline earth metal fluorides and oxaides or iodides as described above.

Alternatively, the molten salt bath may be a molten halide bath. Alternatively, it may be at least one kind of molten salt selected from the group consisting of carbonate, phosphate, ferrate, aluminate and silicate. Alternatively, the molten salt may be a fluoride containing halide bath. The molten salt bath is a fluoride-containing carbonate.
It may be at least one kind of molten salt selected from the group consisting of phosphate, ferrate, aluminate and silicate.

As a concrete representative example, KCl-BaC
1 ₂ as a basic composition, and as a fluoride, for example, N 2
The thing which added aF is mentioned. Other typical molten chloride baths include NaCl, LiCl, and CaC.
l _{2 and the} like are exemplified. Further, as the fluoride, the N
In addition to aF, KF, LiF, CaF ₂ , BaF _{2 and the} like can be mentioned. The alkali metal chloride-alkaline earth metal chloride-alkali metal fluoride bath composition is preferably selected. For example, the specific composition ratio is KCl
In the case of a —BaCl ₂ —NaF system, KCl is 5 to 95 mol%, BaCl ₂ is 5 to 95 mol%, and NaF is 5 to 50 mol%.
Mol%.

As a modification, in the molten salt bath,
In place of the chloride, oxalate, iodide, or fluoride may be used. Even in that case, the oxalate, iodide, or fluoride of alkali metal and alkaline earth metal, respectively, may be used. It may be appropriately selected from iodide or fluoride. In addition, the molten salt bath may be a molten salt bath of carbonate, phosphate, ferrate, aluminate, or silicate. Even in these cases, salts of alkali metals or alkaline earth metals are preferable. Therefore, in the case of carbonate, as a carbonate of an alkali metal or an alkaline earth metal, for example, Li ₂ C
O ₃ , K ₂ CO ₃ , Na ₂ CO ₃ , SrCO ₃ , BaC
O ₃ is preferred. As the phosphate, as a phosphate of an alkali metal or an alkaline earth metal, for example, NaP
O ₃ , KPO ₃ , LiPO ₃ , KH ₂ PO ₄ , K ₂ HP
O ₄ , NaHPO ₄ , Sr ₃ (PO ₄ ) ₂ , Ca (PO
₄ ) ₂ and BaHPO ₄ are preferred. In addition, as the ferrate, as the ferrate of an alkali metal or an alkaline earth metal, for example, K ₂ Fe ₂ O ₄ and CaFe ₂ O ₄ are suitable. Alternatively, in the case of aluminate, similarly, as an aluminate of alkali metal or alkaline earth metal, K ₂ A
l ₂ O ₄ , NaAlO ₂ and BaAl ₂ O ₄ are preferred. Alternatively, in the case of silicate, the same silicate of alkali metal or alkaline earth metal, such as CaSi
O ₃ , Na ₂ SiO ₃ , Li ₂ SiO ₃ , BaSi
O ₃ and Mg ₂ Si ₃ O ₈ are suitable.

The coated diamond powder according to the present invention may, if necessary, be provided before the dipping treatment in order to form a coating film of a substance consisting of a binder and / or a sintering aid derived from the dipping method. Alternatively, the diamond powder surface may be coated with a substance in advance. For example, when forming a thick coating film made of a target metal carbide on the surface of diamond powder, it is preferable to use diamond powder coated with carbon. The method of coating the substance in advance is not particularly limited, but for example, electroplating method, electroless plating method, clad method, physical vapor deposition method (sputtering method, ion plating method, etc.), chemical vapor deposition method, etc. Is preferred. However, when the diamond powder is subjected to the soaking treatment,
A coating film of carbide is formed by the chemical reaction.

Such an immersion treatment may be repeated two or more times by using another kind of target metal.

According to another embodiment, an oxide of boron (B) and an alloy containing boron or a carbide containing boron (for example, B ₄ C) is used in the fluoride-containing molten halide bath.
Etc.) to prepare an immersion bath, and then diamond powder or Ti, Cr, V, W, Mo, Zr, Hf, N
A coated diamond powder having a boron compound layer formed on the surface thereof, characterized in that the diamond powder coated with a metal or a metal compound selected from b, Ta, Ni and alloys thereof is immersed in an immersion bath for an appropriate time. It may also depend on the manufacturing method.

The above Ti, Cr, V, W, Mo, Z
The coating means of the diamond powder coated with a metal or a metal compound selected from r, Hf, Nb, Ta, Ni and alloys thereof is not particularly limited, but for example, conventional electroplating method, electroless method, etc. A plating method, a clad method, a physical vapor deposition method (a sputtering method, an ion plating method, etc.), a chemical vapor deposition method, or the like can be used.

The type of metal of the target metal compound is not particularly limited as long as it is within the range applicable to the binder and / or the sintering aid of the present invention, but it has been considered difficult to form a coating film as compared with the prior art. Existing metals such as Si, Cr, V, B,
Preferred examples include transition metals of groups 4a, 5a and 6a of the periodic table such as W, Mo, Ti, Zr, Hf, Nb and Ta.

The metal, which has been conventionally difficult to form a coating film, such as Si, Cr, V, B, W, Mo or T.
i, Zr, Hf, Nb, Ta, etc. Periodic Table 4a, 5a,
When a group 6a transition metal or the like is released without forming these compounds in the chemical reaction derived from the above immersion treatment,
Sintering the diamond powder provided with the coating film,
In either case of forming a compound or after the sintering, when the free metal remains unreacted, it effectively acts as a binder and / or a sintering aid.

On the diamond powder surface according to the present invention,
A natural and / or artificial diamond powder is used as the diamond raw material for the coated diamond powder, which is provided with a coating film of a substance that is derived from the dipping method and that is composed of a binder and / or a sintering aid. The diamond powder is not particularly limited in particle size, but when a fine and uniform structure is desired, for example, a diamond powder having a particle size of about 1 μm is used, and the diamond powder is dipped by a dipping method. You can use it.

According to the present invention, the amount of the substance, which is derived from the dipping method and is a binder and / or a sintering aid, which is coated on the surface of the diamond powder, is, for example, the dipping temperature or dipping time. Although controlled by the immersion treatment conditions such as, under the same immersion treatment conditions, the addition amount changes depending on the particle size of the powder, for example, when the particle size is small,
The amount of addition increases relatively. Therefore, considering the above points,
An arbitrary amount from a trace amount to a large amount is added.

On the diamond powder surface according to the present invention,
Powders of metals or compounds which are derived from the dipping method and which are mixed with a coated diamond powder provided with a coating film of a substance consisting of a binder and / or a sintering aid are represented by Periodic Tables 2a, 3 and 3.
Powders of at least one of a, 4a, 5a, 6a, 7a, group 8 transition metals, rare earth metals, B, Si, Al, or a compound containing one or more of these are used. More specifically, the periodic table 2a, 3a, 4a, 5a, 6
a, 7a, 8 group transition metal, rare earth metal, B, Si, A
l, or their carbides, oxides, nitrides, oxycarbides,
A powder made of at least one of oxynitride, carbonitride, oxycarbonitride, boride, and silicide is used. Preferably C
(Diamond), SiC, B ₄ C, Cr ₃ C ₂ , Ti
C, ZrC, WC, W ₂ C, HfC, NbC, TaC,
Ta ₂ C, VC, Mo ₂ C, Si ₃ N ₄ , TiN, Zr
N, Si ₂ N ₂ O, AlN, HfN, V _X N (x = 1-
3), NbN, TaN, Ta ₂ N, TiB, TiB ₂ ,
ZrB ₂ , VB, V ₃ B ₂ , VB ₂ , NbB ₂ , Nb
B, TaB ₂ , TaB, MoB, MOB ₄ , MoB ₂ ,
Mo ₂ B, WB, W ₂ B ₅ , WB ₄ , LaB ₆ , BP,
_{B 13 P 2, MoSi 2,} Al 2 O 3, ZrO 2 (Y 2
O _3, MgO or CaO stabilizer was added partially stabilized zirconia: PSZ, or tetragonal zirconia polycrystals: T
ZP), MgAl ₂ O ₄ (spinel), Al ₂ SiO ₅
A powder consisting of at least one type of (mullite) is selected.

Alternatively, on the surface of the powder, the second periodic table
a, 3a, 4a, 5a, 6a, 7a, Group 8 transition metal, rare earth metal, B, Si, Al, or a coating powder provided with a coating of at least one of compounds containing one or more of these Use the body. More specifically, the periodic table Nos. 2a, 3a, 4a, 5a, 6a, 7 are formed on the surface of the powder.
a, at least Group 8 transition metal, rare earth metal, B, Si, Al, or their carbides, oxides, nitrides, oxycarbides, oxynitrides, carbonitrides, oxycarbonitrides, borides, and silicides A coated powder provided with a coating of one type is used. Preferably, B, Ti, Zr, H is added to the surface of the powder.
f, Ta, Nb, V, Si, Mo, SiC, TiC, Z
rC, B ₄ C, WC, HfC, TaC, NbC, Si ₃
N ₄ , TiN, ZrN, AlN, HfN, TaN, Ti
B, TiB ₂ , ZrB ₂ , LaB ₆ , MOSi ₂ , B
A coating powder provided with a coating of at least one of P and Al ₂ O ₃ is selected. The coating method for providing the coating may be an immersion method, an electroplating method, an electroless plating method, a clad method, a physical vapor deposition method (for example, a sputtering method, an ion plating method, etc.), a chemical vapor deposition method, or the like. Can be done. Alternatively, the powder can be selected by coating the powder with an oxide film on the surface of the powder by oxidizing the powder in an oxidizing atmosphere.

On the diamond powder surface according to the present invention,
The minor diameter is 500 μm or less, and the ratio of the major diameter to the minor diameter is 500 μm or less, which is mixed with the coated diamond powder provided with the coating film of the substance that is derived from the dipping method and is composed of the binder and / or the sintering aid. In the present invention, a fibrous substance composed of at least one kind of metal or compound having a shape of 2 or more is a rod-like material having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more, and / or Alternatively, long fibers made of continuous fibers by melt-spinning to form a fiber and / or short fibers made of self-shaped fibers in which crystals themselves have a fiber shape and / or whiskers (w) formed by unidirectionally crystal growing into a fiber shape
isker). The whisker (beard crystal)
Is a true crystal that is defined by the fact that in its formation, the phenomenon of a phase change or a chemical reaction affecting the entire volume does not occur, and / or a crystal of a crystal produced by a phase change or a chemical change affecting the entire volume. By growing only the plane, a whisker in a broad sense indicating a single crystal that has become a long needle-like crystal and / or a cross-sectional area of 8 × 10 ⁻⁵ in ²
In the following, the whiskers are single crystals having a length of 10 times or more the average diameter.

As the fibrous substance, the periodic table 2a,
3a, 4a, 5a, 6a, 7a, Group 8 transition metal, rare earth metal, B, Si, Al, or at least one kind of a compound containing one or more kinds thereof, and a minor axis of 500.
A fibrous substance having a shape of not more than μm and having a ratio of the major axis to the minor axis of 2 or more is used. More specifically, the periodic table group 2a, 3a, 4a, 5a, 6a, 7a, 8 group transition metal, rare earth metal, B, Si, Al, or their carbides, oxides, nitrides, oxycarbides, Oxynitride, carbonitride,
A fibrous substance made of at least one kind of oxycarbonitride, boride, and silicide and having a short diameter of 500 μm or less and a ratio of the long diameter to the short diameter of 2 or more is used. Suitably, for example, Ta, Zr, Cr, Si, C, W, B,
Mo, Nb, V, Al ₂ O ₃ , Fe ₂ C, B ₄ C, Si
C, TiC, Fe ₃ C, Ta ₂ C, Nb ₂ C, Si ₃ N
₄ , a fibrous substance made of at least one kind of Cr ₂ N, AlN, Si ₂ ON ₂ and TiN, and having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more is selected. .

Alternatively, a coated fibrous substance having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more is formed on the surface of the fibrous substance by periodic table 2a,
3a, 4a, 5a, 6a, 7a, Group 8 transition metal, rare earth metal, B, Si, Al, or a coating made of at least one kind of a compound containing one or more of these, for a minor axis A coating material having a shape having a ratio to the major axis of 2 or more is used. More specifically, the minor axis is 500 μm
In the following, the coated fibrous material having a shape in which the ratio of the major axis to the minor axis is 2 or more is formed on the surface of the fibrous material by the periodic table groups 2a, 3a, 4a, 5a, 6a, 7a and 8 groups. Transition metal, rare earth metal, B, Si, Al, or their carbides, oxides, nitrides, oxycarbides, oxynitrides, carbonitrides,
A coating material is used which is made of at least one of oxycarbonitride, boride, and silicide, and which has a coating and has a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more. . Suitably, for example, B, Ti, Zr, Hf, Ta, Nb, V, SiC, on the surface of the fibrous substance,
TiC, ZrC, B ₄ C, WC, HfC, TaC, Nb
C, Si ₃ N ₄ , TiN, ZrN, AlN, HfN, T
aN, TiB, TiB ₂ , ZrB ₂ , LaB ₆ , MoS
A coated fibrous substance having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more, which is provided with a coating composed of at least one of i ₂ , BP, and Al ₂ O ₃ is selected. . The coating method for providing the coating includes dipping, electroplating, electroless plating, cladding,
Physical vapor deposition (eg, sputtering, ion plating, etc.), chemical vapor deposition, etc. can be used. Alternatively, the coated fibrous substance having a shape in which the minor axis is 500 μm or less and the ratio of the major axis to the minor axis is 2 or more is obtained by oxidizing the fibrous material in an oxidizing atmosphere. A coated fibrous substance having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more, in which an oxide film is provided on the surface of the fibrous substance, can be selected.

According to another aspect, a coated diamond powder obtained by providing a coating film of a substance made of a dipping method, the substance being a binder and / or a sintering aid, on the surface of the diamond powder. Since the surface of each of the particles is uniformly coated with the above-mentioned substance consisting of the binder and / or the sintering aid, the particles of the coated diamond powder are
Or, if a proper amount is mixed so as to come into contact with the circumference of each particle of the diamond powder without providing the coating of the substance consisting of the sintering aid, as described above, it is sure that each particle of the diamond powder has the binder and It is preferable that the sintering aid can be distributed. The diamond powder not provided with the coating of the substance made of the binder and / or the sintering aid is
The particle diameter of the diamond powder is relatively large with respect to the coated diamond powder obtained by forming a coating film of a substance made of a binder and / or a sintering aid on the surface of the diamond powder by the dipping method. If it is large, even if a relatively large amount is added, as described above,
Binders and / or sintering aids can be distributed around the diamond powder particles. More specifically, the coated diamond powder is 50% to 99.9% by volume.
%, The balance being 50% to 0.
Mix 1%. More preferably, 60% to 99.5% by volume of the coated diamond powder and 40% to 0.5% by volume of the remaining diamond powder may be mixed.

Thus, the coated diamond powder, which is provided with a coating film of a substance consisting of a binder and / or a sintering aid, which is derived from the dipping method, on the surface of the diamond powder is used alone or Coated diamond powder and the rest is the powder and / or the coated powder and / or the minor axis is 500 μm
In the following, a fibrous substance having a shape in which the ratio of the major axis to the minor axis is 2 or more and / or the coated fibrous material having a shape in which the minor axis is 500 μm or less and the ratio of the major axis to the minor axis is 2 or more. The mixture obtained by mixing the substances is powdered, or after stamping and molding, it is sintered for an appropriate period of time at an ultrahigh pressure of 2000 MPa or higher and a high temperature.

As the ultrahigh pressure device, a cubic type, a tetra type, a girdle type, a belt type and the like can be applied, and there is no particular limitation.

The pressure for pressurizing the sample with good reproducibility is
Since an ultrahigh pressure device such as the cubic type ultrahigh pressure device is used, the pressure is 2000 MPa or more. Even if the sintering temperature is slightly out of the thermodynamically stable region of the diamond, when a material that does not catalyze the phase transition from diamond to graphite is used as the binder and / or the sintering aid. It doesn't matter.

However, more preferably, it is sintered in a thermodynamically stable region of diamond under ultrahigh pressure and high temperature of 2000 MPa or more.

As an example, the production of a diamond sintered body using a cubic type ultra-high pressure apparatus will be described. First, the surface of the diamond powder is coated with a binder and / or a sintering aid by a dipping method. The coated diamond powder provided with the film is embossed into a pellet shape,
This is wrapped with zirconium foil, surrounded by a hexagonal boron nitride (h-BN) molded body, and a graphite tube heater is arranged on the outer side. Outside the heater, pyrophyllite from which water of crystallization has been removed by heat treatment at 700 ° C. is arranged as a solid pressure medium. The sample thus constructed is placed in a cubic type ultra high pressure device,
The pressure is increased to a predetermined pressure, then the temperature is raised to a predetermined temperature, and sintering is performed for an appropriate time. After sintering, the temperature is lowered and the pressure is reduced. The pressure medium is taken out from the cubic type ultrahigh pressure device, and the sample is taken out from the pressure medium. In this way, a characteristic high-density diamond sintered body having a uniform and fine microstructure in which the distribution of the binder and / or the sintering aid is controlled is obtained.

[0040]

The preferred embodiments of the present invention will be described below.

[0041]

[First Embodiment] As a dipping bath, KCl, BaCl ₂ , N
aF is used as a base salt, and K ₂ TiF ₆ and Ti metal are added thereto to prepare a molten mixed salt bath.
The fine diamond powder, which is the raw material for the sintered body, of m, was put in, and subjected to a dipping treatment accompanied by a disproportionation reaction under the condition of 900 ° C. for 2 hours. Then, a chemical reaction between diamond and Ti metal formed a TiC coating film as shown in the powder X-ray diffraction pattern of FIG. The powder was washed with distilled water and then vacuum dried to obtain a coated diamond powder.

[0042]

[Figure 1]

Generally, since diamond is not conductive, it is charged up when it is observed under a free electron microscope, and unless the conductive material is vapor-deposited, the portion where the coating film is not formed shines white. It becomes unobservable. However, since the TiC coated in the first embodiment is conductive, it is easy to see how the coating film is distributed by observing the coated diamond powder with a scanning electron microscope. FIG. 2 is an electron micrograph (× 5000) of the coated diamond powder, in which vapor deposition of a conductive substance for observing the coated diamond powder with an electron microscope is not performed at all. As shown in FIG. 2, there was no charge-up part, and a very clear image was observed. Moreover, each of the individual particles of the coated diamond powder had a dense and smooth coating. It can be seen that it is covered with a film.

[0044]

[Fig. 2]

The coated diamond powder has an outer diameter of 6 mm,
Molded to a height of 2 mm, and stamped with zirconium (Z
r) Wrap with foil, and then hexagonal boron nitride (hB
N) Embedded in a pressure medium in which the molded body is placed,
Vacuum drying was carried out at 10 ⁻³ torr for one day to remove low boiling point impurities. This was set in a cubic type ultra-high pressure device, and the pressure was first raised to 5.5 GPa at room temperature, then 15
The temperature was raised to 00 ° C., the temperature was kept for 30 minutes, and then the temperature was lowered to lower the pressure.

When the obtained sintered body was examined by X-ray diffraction, as shown in FIG. 3, the composition was the same as that of the coated diamond powder, and only diamond and TiC were found. According to X-ray quantitative analysis, the sintered body had a volume ratio of diamond and TiC of about 50% and 50%, respectively.

[0047]

[Figure 3]

The surface of the obtained sintered body was polished with a diamond paste, and the Pickers microhardness was measured. Hv (0.5 / 10) of the sintered body obtained in the first embodiment of the present invention
Was as high as about 4000. Moreover, the hardness of the sintered body of the first example was constant over the entire hardness measurement surface of the sintered body, and there was almost no variation.

FIG. 4 shows an electron micrograph (× 5000) of the polished surface obtained by subjecting the polished surface of the sintered body of the first embodiment to ordinary gold vapor deposition for observation. As is clear from FIG. 4, there were no pores in the sintered body, and it was possible to sinter to a relative density of 100%. Moreover, there were no unsintered parts. Since the diamond particles in the sintered body are particularly fine, diamond and TiC cannot be clearly distinguished from each other, but TiC is uniformly distributed, and a dense, uniform and controlled sintering aid distribution is obtained. It can be easily seen that the sintered body has a characteristic. Moreover, the diamond particles do not grow as compared with the diamond powder as the raw material, and the diamond and Ti in the molten salt bath chemically react with each other to form a coating film. However, there is also a feature that it is finer than the raw material before coating. This is very convenient for the mechanical properties of the sintered body and is ideal. These features are shown in FIG.
Compared with an electron micrograph (× 5000) of the polished surface obtained by subjecting the polished surface of a typical commercially available diamond sintered body cutting tool to ordinary gold vapor deposition for observation, the commercially available diamond sintered body In the cutting tool, there are many deficient sintering aids and binders, and unsintered parts are found there. Further, it is clearly understood that the diamond particles of the cutting tool are extremely coarse, which is a big difference from the first embodiment of the present invention.

As described above, although diamond is originally extremely difficult to sinter, the coated diamond powder particles of the present invention are particles that are relatively easy to sinter under ultrahigh pressure and high temperature. It behaved like a fine, dense, strong, and highly hard structure.

[0051]

[Figure 4]

[0052]

[Figure 5]

[0053]

[Second Embodiment] 90% by volume of coated diamond powder coated with TiC, which is obtained by performing the dipping treatment under the same conditions as in the first embodiment, and the balance is diamond powder not coated (particle size). 0-1 μm) by volume 10% using a mortar,
The mixture was wet-mixed in acetone and then vacuum dried to obtain a mixed powder. The mixed powder was press-molded to have an outer diameter of 6 mm and a height of 2 mm, and was set in a cubic type ultra-high pressure apparatus as in the first embodiment. First, the pressure was increased to 5.3 GPa at room temperature and then to 1480 ° C. The temperature was raised, the temperature was maintained for 30 minutes, and then the temperature was lowered to lower the pressure. The surface of the obtained sintered body was polished with diamond paste, and the Vickers microhardness was measured. As a result, Hv (0.5 / 10) was about 4500, which was a high hardness. When the crystal phase of this sintered body was examined by powder X-ray diffraction, only diamond and TiC were found as in the first example. Also, although not shown, in the second embodiment as well, the sintered body does not have any pores like the polished surface of the sintered body of the first embodiment and can be sintered to a relative density of 100%. , Because there was no unsintered part at all,
A dense and uniform distribution of the sintering aid was established, and the uncoated diamond particles were not aggregated, and a sintered body uniformly dispersed between the coated diamond particles was obtained. In the second example, the coated diamond particles functioned as an apparent base material. Therefore, by adding an appropriate amount of uncoated diamond powder, fine adjustment of the added amount can be performed by this simple method. Needless to say, the volume fraction of uncoated diamond powder can be increased by using uncoated diamond powder having a different particle size, for example, a larger particle size.

[0054]

[Third Embodiment] The first embodiment is the same as the first embodiment except that the immersion treatment time is 1 hour.
80% by volume of the coated diamond powder coated with TiC, which was obtained by performing the dipping treatment under the same conditions as in the example, the balance being alumina powder (Al ₂ O ₃ ; average particle size 0.2 μm,
Purity 99.99%) 20% by volume using a mortar,
The mixture was wet-mixed in acetone and then vacuum dried to obtain a mixed powder. The mixed powder was press-molded to have an outer diameter of 6 mm and a height of 2 mm, and was set in a cubic type ultra-high pressure apparatus as in the first embodiment. First, the pressure was increased to 5.0 GPa at room temperature and then to 1450 ° C. The temperature was raised, the temperature was maintained for 30 minutes, and then the temperature was lowered to lower the pressure. In the obtained sintered body, according to the X-ray quantitative analysis, diamond, TiC and Al ₂ O
₃ was about 60%, 20% and 20%, respectively.
The surface of the sintered body is polished with diamond paste,
When the Vickers microhardness was measured, it was Hv (0.5 / 1
0) had a high hardness of about 4,800. When the crystal phase of this sintered body was examined by powder X-ray diffraction, only diamond and TiC were found as in the first example except for Al ₂ O ₃ . Also in the third embodiment, the sintered body is
A dense and uniform composite sintered body was obtained in which the coated diamond particles functioned as an apparent base material, and the Al ₂ O ₃ particles were not aggregated and were uniformly dispersed between the coated diamond particles.

[0055]

[Fourth Embodiment] The coated diamond powder coated with TiC, which is obtained by performing the dipping treatment in the same manner as the third embodiment, has a volume of 8
0%, balance is silicon carbide powder (SiC; average particle size 1μ
m, purity 99%) by volume, 20% by volume was wet-mixed in acetone using a mortar and then vacuum-dried to obtain a mixed powder. The mixed powder was press-molded to have an outer diameter of 6 mm and a height of 2 mm, and was set in a cubic type ultra-high pressure apparatus as in the first embodiment. First, the pressure was raised to 5.5 GPa at room temperature and then raised to 1500 ° C. Warm up, hold for 30 minutes, then cool down,
Reduced pressure. According to the X-ray quantitative analysis, diamond, TiC and SiC in the obtained sintered body were about 60%, 20% and 20%, respectively. The surface of the sintered body was polished with diamond paste, and the Vickers microhardness was measured, and Hv (0.5 / 10) was about 500.
The hardness was 0 and high. When the crystal phase of this sintered body was examined by powder X-ray diffraction, only diamond and TiC were detected as in the first example except for SiC. Also in the fourth embodiment, the sintered body is dense, uniform,
Moreover, the coated diamond particles functioned as an apparent base material, and a composite sintered body was obtained in which the SiC particles were not aggregated and were uniformly dispersed between the coated diamond particles.

[0056]

Fifth Embodiment 90% by volume of coated diamond powder coated with TiC, obtained by immersion treatment under the same conditions as in the first embodiment, the balance being silicon carbide whiskers (SiC;
Minor axis 0.1 μm, average length 5 μm) 10% by volume
Was wet-mixed in acetone using a mortar and then vacuum-dried to obtain a mixed powder. The mixed powder was press-molded to have an outer diameter of 6 mm and a height of 2 mm, and was set in a cubic type ultra-high pressure apparatus in the same manner as in the first embodiment. First, the pressure was raised to 5.5 GPa at room temperature, and then 1500 ° C. The temperature was raised, the temperature was maintained for 30 minutes, and then the temperature was lowered to lower the pressure. In the obtained sintered body, according to the X-ray quantitative analysis, diamond,
TiC and SiC are about 45%, 45% and 1 respectively.
It was 0%. The surface of the sintered body was polished with a diamond paste, and the Vickers microhardness was measured.
(0.5 / 10) was a high hardness of about 4000. When the crystal phase of this sintered body was examined by powder X-ray diffraction, diamond, TiC and SiC were all found, as in the fourth example. Also in the fifth embodiment, the sintered body is a dense and uniform composite sintered body in which the coated diamond particles function as an apparent base material, and the SiC whiskers do not agglomerate and are uniformly dispersed between the coated diamond particles. A unity was obtained.

[0057]

As described above, according to the diamond sintered body and the method for producing the same of the present invention, which have been described in detail above, the diamond powder is used as the binder and / or the sintering aid substance in an arbitrary amount from a trace amount to a large amount. The coated diamond powder obtained by uniformly coating the surface of each of the particles is used alone or with the coated diamond powder, and the remainder is the powder and / or the coated powder and / or the short diameter. A fibrous substance having a shape of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more, and / or the coated fiber having a shape of the minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more. The mixture formed by mixing the substances in powder form, or after embossing,
Uniform and dense, characterized by being manufactured by a method for manufacturing a diamond sintered body characterized by being sintered under an ultrahigh pressure of 2000 MPa or higher and a high temperature, and a method for manufacturing the diamond sintered body. It is possible to provide a high-performance, high-density, high-density diamond sintered body that is strongly sintered by a simple and inexpensive means. Since the diamond sintered body has dramatically improved performance, for example,
The range of application as a variety of high-hardness sintered bodies will be greatly expanded. Therefore, the present invention greatly contributes to the development of the industry.

[Brief description of drawings]

FIG. 1 is an X-ray diffraction pattern diagram of TiC-coated diamond powder derived from an immersion method.

FIG. 2 is a drawing-substitute electron micrograph (x5) showing the particle structure of TiC-coated diamond powder derived from the dipping method.
000).

FIG. 3 is an X-ray diffraction pattern diagram of a diamond sintered body obtained by sintering TiC-coated diamond powder derived from an immersion method under ultrahigh pressure and high temperature.

FIG. 4 is a drawing-substitute electron micrograph (x5000) showing a grain structure on a polished surface of a diamond sintered body of the present invention.
Is.

FIG. 5 is a drawing-substitute electron micrograph (x5000) showing a particle structure on a polished surface of a typical commercially available diamond sintered body cutting tool as a comparative example.

Claims (37)

[Claims] 1. A coated diamond powder, which is obtained by immersing a coating film of a substance consisting of a binder and / or a sintering aid on the surface of the diamond powder, in the form of powder or embossing. After the forming, a method for producing a diamond sintered body, which comprises sintering at an ultrahigh pressure of 2000 MPa or higher and a high temperature. 2. A coated diamond powder, which comprises a coating film of a substance consisting of a binder and / or a sintering aid, which is derived from a dipping method and is provided on the surface of the diamond powder in a volume of 1% to 9%.
9.9%, the balance being powder of metal or compound, 9% by volume
A mixed powder of 9% to 0.1% is mixed in powder form or after embossing, and then sintered under ultrahigh pressure and high temperature of 2000 MPa or more. Manufacturing method. 3. A coated diamond powder having a coating film of a substance made of a binder and / or a sintering aid, which is derived from an immersion method, provided on the surface of the diamond powder, the volume of 1% to 9%.
9.9%, the balance being 99% to 0.1% by volume of coated powder in which a coating of at least one kind of metal or compound is provided on the surface of powder of metal or compound Mix powders in powder form or after stamping 2
A method for producing a diamond sintered body, which comprises sintering under an ultrahigh pressure of 000 MPa or more and a high temperature. 4. A coated diamond powder comprising a coating film of a substance made of a binder and / or a sintering aid, which is derived from an immersion method, provided on the surface of the diamond powder in a volume of 50% to 9%.
9.9%, the balance is a fibrous substance consisting of at least one kind of metal or compound having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more by volume.
A method for producing a diamond sintered body, characterized in that a mixture obtained by mixing 0% to 0.1% is sintered at the same time or after embossing at an ultrahigh pressure of 2000 MPa or higher and a high temperature. . 5. A coated diamond powder, wherein the mixture is provided on the surface of the diamond powder with a coating film of a substance that is derived from an immersion method and that is composed of a binder and / or a sintering aid,
60% to 99.5% by volume, the balance is 500 μm in minor axis
In the following, the mixture is formed by mixing 40% to 0.5% by volume of a fibrous substance composed of at least one kind of metal or compound having a shape in which the ratio of the major axis to the minor axis is 2 or more. The method for producing a diamond sintered body according to claim 4, wherein. 6. A coated diamond powder, which comprises a coating film of a substance made of a binder and / or a sintering aid, which is derived from an immersion method, on the surface of the diamond powder, the volume of the coated diamond powder being 50% to 9%.
9.9%, with the balance being 500 μm or less in the minor axis, and the ratio of the major axis to the minor axis in the ratio of 2 or more, the surface of the fibrous substance made of at least one kind of the metal or the compound, the metal or the compound A mixture of 50% to 0.1% by volume of a coated fibrous substance provided with a coating of at least one kind is used at the same time or after embossing, and an ultrahigh pressure of 2000 MPa or more. A method for producing a diamond sintered body, which comprises sintering at a high temperature. 7. A coated diamond powder, wherein the mixture is provided on the surface of the diamond powder with a coating film of a substance derived from an immersion method and comprising a binder and / or a sintering aid,
60% to 99.5% by volume, the balance is 500 μm in minor axis
In the following, a coated fiber in which a coating made of at least one kind of metal or compound is provided on the surface of a fibrous substance made of at least one kind of metal or compound in a shape in which the ratio of the major axis to the minor axis is 2 or more. 40% by volume of substances
7. The method for producing a diamond sintered body according to claim 6, wherein the mixture is formed by mixing 0.5% to 0.5%. 8. A coated diamond powder, comprising a coating film of a substance made of a binder and / or a sintering aid, which is derived from a dipping method, provided on the surface of the diamond powder in a volume of 1% to 9%.
9.9%, with the balance being a fibrous substance consisting of at least one kind of metal or compound having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more, and a powder of the metal or the compound. The ratio is 0.1: 100 to 100: 0 by volume.
The mixture obtained by mixing 99% to 0.1% by volume of the mixture consisting of
A method for producing a diamond sintered body, which comprises sintering at an ultrahigh pressure of 2000 MPa or more and a high temperature. 9. A coated diamond powder having a coating film of a substance made of a binder and / or a sintering aid, which is derived from an immersion method, provided on the surface of the diamond powder, the volume of 1% to 9%.
9.9%, the balance is a fibrous substance made of at least one kind of metal or compound having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more, and metal or compound powder The ratio of the coated powder in which the coating of at least one kind of metal or compound is provided on the surface of 0.
A mixture consisting of 1: 100 to 100: 0.1 is mixed with 9 by volume.
A method for producing a diamond sintered body, characterized in that a mixture obtained by mixing 9% to 0.1% is sintered in powder form or after embossing under ultrahigh pressure and high temperature of 2000 MPa or more. . 10. A coated diamond powder having a coating film of a substance made of a binder and / or a sintering aid, which is derived from an immersion method, provided on the surface of the diamond powder, the volume of 1% to 9%.
9.9%, the balance being at least 500 μm in minor axis, and at least a metal or compound on the surface of a fibrous substance made of at least one kind of metal or compound in a ratio of the major axis to the minor axis of 2 or more. 99% to 0.1% by volume of a mixture in which the ratio of the coated fibrous substance provided with a coating of one kind and the powder of metal or compound is 0.1: 100 to 100: 0.1 by volume A method for producing a diamond sintered body, characterized in that the mixture obtained by mixing is mixed in powder form or after embossing, and then sintered under ultrahigh pressure and high temperature of 2000 MPa or more. 11. A coated diamond powder comprising a coating film of a substance, which is derived from an immersion method and is composed of a binder and / or a sintering aid, provided on the surface of the diamond powder, the volume of 1% to 9%.
9.9%, the balance being at least 500 μm in minor axis, and at least a metal or compound on the surface of a fibrous substance made of at least one kind of metal or compound in a ratio of the major axis to the minor axis of 2 or more. The ratio of the coated fibrous substance provided with a coating made of one type to the coated powder provided with a coating made of at least one type of metal or compound on the surface of the powder of metal or compound is 0.1: by volume. 100-100:
By mixing 99% to 0.1% by volume of the mixture of 0.1, a mixture in the form of powder or after embossing may be sintered at an ultrahigh pressure of 2000 MPa or higher and at a high temperature. A method for producing a characteristic diamond sintered body. 12. A coating film comprising a substance consisting of a binder and / or a sintering aid, which is derived from an immersion method, on the surface of the diamond powder, wherein the coated diamond powder is formed by a dipping method.
A coated diamond powder provided by the manufacturing method of No. 07380, claim 1, claim 2,
Claim 3, Claim 4, Claim 5, Claim 6, Claim 7,
The method for manufacturing a diamond sintered body according to claim 8, claim 9, claim 10, or claim 11. 13. A coating film, wherein the coated diamond powder is a diamond powder, which is derived from an immersion method and is made of a substance consisting of a binder and / or a sintering aid.
Claim 1, Claim 2, Claim 3, Claim 4, Claim 5, Claim 6, Claim 7, characterized by comprising coated diamond powder provided by the manufacturing method of No. 168. The method for producing a diamond sintered body according to claim 8, claim 9, claim 10, or claim 11. 14. The method according to claim 1, wherein the substance that is derived from the immersion method and that is a binder and / or a sintering aid is a compound of a target metal that is derived from the immersion method. 2, claim 3, claim 4, claim 5, claim 6, claim 7, claim 8, claim 9, claim 10, claim 12, or claim 13 Body manufacturing method. 15. The coated diamond powder is provided with a coating film made of at least one of carbide, boride, nitride and silicide of a target metal derived from an immersion method on the surface of the diamond powder. Claim 1, claim 2, claim 3, claim 4, claim 5, claim 6, claim 7, claim 8, claim 9, characterized in that they consist of coated diamond powder. The method for producing a diamond sintered body according to claim 10, claim 11, claim 12, claim 13 or claim 14. 16. A method for forming a coating film comprising at least one of a target metal carbide, boride, and nitride on the diamond powder surface by an immersion method, the method comprising: By preparing a dipping bath composed of a molten salt containing a metal, and dipping the diamond powder to be treated in the dipping bath for an appropriate time, a carbide of the desired metal is formed on the diamond powder surface. Claim 1, Claim 2, Claim 3, Claim 4, and Claim 4 which consist of coated diamond powder which provides a coating film which consists of at least 1 sort (s) of this, a boride, and a nitride. 5, claim 6, claim 7, claim 8, claim 9, claim 10, claim 11, claim 12, claim 14
Alternatively, the method for producing a diamond sintered body according to claim 15. 17. A method of forming a coating film of the coated diamond powder on the surface of the diamond powder by a dipping method, the coating film comprising at least one kind of carbide, boride, nitride and silicide of a target metal. , A dipping bath is prepared by adding at least one of a simple substance metal or alloy of the intended metal, a halide, and an oxide to the molten salt bath, and dipping diamond powder into the dipping bath to obtain the target metal. A coating film made of at least one kind of carbide, boride, nitride and silicide of a target metal on the surface of the diamond powder by a manufacturing method comprising coating the surface of the diamond powder with the compound of 2. A coated diamond powder comprising:
Claim 2, Claim 3, Claim 4, Claim 5, Claim 6,
Claim 7, Claim 8, Claim 9, Claim 10, Claim 1
The method for producing a diamond sintered body according to claim 1, claim 13, claim 14, or claim 15. 18. The method according to claim 1, wherein the substance that is derived from the immersion method and that is a binder and / or a sintering aid is a compound and / or metal that is derived from the immersion method. Claim 2, Claim 3, Claim 4, Claim 5, Claim 6, Claim 7, Claim 8, Claim 9, Claim 10, Claim 1
1, claim 12, claim 13, claim 14, claim 1
The method for producing a diamond sintered body according to claim 5, claim 16 or claim 17. 19. The dipping method involves a disproportionation reaction in which two or more substances are produced as a result of mutual oxidation, reduction or other reaction of one substance with two molecules or more. It is a dipping method, It is characterized by the above-mentioned.
Claim 3, Claim 4, Claim 5, Claim 6, Claim 7,
Claim 8, Claim 9, Claim 10, Claim 11, Claim 1
2, claim 13, claim 14, claim 15, claim 1
The method for producing a diamond sintered body according to claim 6, claim 17, or claim 18. 20. The balance of the powder is the periodic table No. 2a,
3a, 4a, 5a, 6a, 7a, a Group 8 transition metal, a rare earth metal, B, Si, Al, or a powder containing at least one kind of a compound containing one or more kinds thereof, The method for producing a diamond sintered body according to claim 2, claim 3, claim 8, claim 9, claim 10 or claim 11. 21. The balance of the powder is the periodic table No. 2a,
3a, 4a, 5a, 6a, 7a, Group 8 transition metals, rare earth metals, B, Si, Al, or their carbides, oxides,
Nitride, oxycarbide, oxynitride, carbonitride, oxycarbonitride,
A diamond sintered body according to claim 2, claim 3, claim 8, claim 9, claim 10 or claim 11, characterized in that it is a powder of at least one of boride and silicide. Manufacturing method. 22. The remaining coated powder is formed on the surface of the powder by the periodic table Nos. 2a, 3a, 4a, 5a, 6a and 7 of the periodic table.
A coated powder comprising a coating of at least one of a, a Group 8 transition metal, a rare earth metal, B, Si, Al, or a compound containing one or more of these. 3. The method for manufacturing a diamond sintered body according to claim 9 or claim 11. 23. The balance of the coated powder is formed on the surface of the powder by means of Periodic Table Nos. 2a, 3a, 4a, 5a, 6a, and 7a.
a, at least Group 8 transition metal, rare earth metal, B, Si, Al, or their carbides, oxides, nitrides, oxycarbides, oxynitrides, carbonitrides, oxycarbonitrides, borides, and silicides The method for producing a diamond sintered body according to claim 3, claim 9 or claim 11, wherein the method comprises a coated powder comprising a coating of one kind. 24. The remaining fibrous substance having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more is a periodic table 2a, 3a, 4a, 5a, 6
a, 7a, 8 group transition metal, rare earth metal, B, Si, A
or a fibrous substance having a shape with a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more, which is composed of at least one compound containing 1 or more of these. The method for producing a diamond sintered body according to claim 4, claim 5, claim 6, claim 7, claim 8, claim 9, claim 10, or claim 11. 25. The remaining fibrous substance having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more is a periodic table 2a, 3a, 4a, 5a, 6
a, 7a, 8 group transition metal, rare earth metal, B, Si, A
l, or their carbides, oxides, nitrides, oxycarbides,
A fibrous substance made of at least one kind of oxynitride, carbonitride, oxycarbonitride, boride, and silicide and having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more. The method for producing a diamond sintered body according to claim 4, claim 5, claim 6, claim 7, claim 8, claim 9, claim 10 or claim 11, characterized in that 26. The remaining fibrous substance having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more is formed on the surface of the fibrous substance according to Table 2 of the periodic table.
a, 3a, 4a, 5a, 6a, 7a, a Group 8 transition metal, a rare earth metal, B, Si, Al, or a coating containing at least one kind of a compound containing one or more of these, The coated fibrous material having a diameter of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more. 12. The claim 6, claim 7, claim 10 or claim 11. Manufacturing method of diamond sintered body. 27. A coated fibrous material having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more in the remaining portion is provided on the surface of the fibrous material in Periodic Table 2a. 3a, 4a, 5a, 6a, 7a, Group 8 transition metal, rare earth metal, B, Si, Al, or their carbides, oxides, nitrides, oxycarbides, oxynitrides, carbonitrides,
The coated fibrous material provided with a coating made of at least one of oxycarbonitride, boride, and silicide, and the coated fibrous material according to claim 6, claim 7, claim 10, or claim 11. Manufacturing method of diamond sintered body. 28. A volume of coated diamond powder, wherein said mixed powder is provided with a coating film of a substance made of a dipping method and comprising a binder and / or a sintering aid on the surface of diamond powder. 50% to 99.9%, and the balance is a mixed powder obtained by mixing 50% to 0.1% by volume of diamond powder by volume.
A method for manufacturing a diamond sintered body according to claim 10, claim 20 or claim 21. 29. A volume of coated diamond powder, wherein said mixed powder has a coating film of a substance, which is derived from an immersion method and is composed of a binder and / or a sintering aid, provided on the surface of said diamond powder. 60% to 99.5% by weight, and the balance being a mixed powder obtained by mixing 40% to 0.5% by volume of diamond powder by volume.
A method for manufacturing a diamond sintered body according to claim 10, claim 20, claim 21 or claim 28. 30. The remaining powder is SiC, TiC,
ZrC, B ₄ C, WC, HfC, TaC, NbC, Si
₃ N ₄ , TiN, ZrN, AlN, HfN, TaN, T
iB, TiB ₂ , BP, Al ₂ O ₃ , Al ₂ SiO
₅ (mullite), ZrO ₂ (Y ₂ O ₃ , MgO or Ca)
A zirconia: PSZ or tetragonal zirconia polycrystal: TZP) added with an O stabilizer and a powder comprising at least one kind of MgAl ₂ O ₄ (spinel). The method for manufacturing a diamond sintered body according to claim 8, claim 9, claim 10, claim 11, claim 20, claim 21, claim 22 or claim 23. 31. The balance of the coated powder, B, Ti, Zr, Hf, Ta, Nb, V, Si, on the surface of the powder.
Mo, SiC, TiC, ZrC, B ₄ C, WC, Hf
C, TaC, NbC, Si ₃ N ₄ , TiN, ZrN, A
1N, HfN, TaN, TiB, TiB ₂ , ZrB ₂ ,
A coated powder comprising a coating made of at least one of LaB ₆ , MoSi ₂ , BP, and Al ₂ O ₃ , which is characterized in that it is a coated powder.
The method for manufacturing a diamond sintered body according to claim 2 or claim 23. 32. The remaining coated powder is a coated powder in which an oxide film is provided on the surface of the powder by oxidizing the powder in an oxidizing atmosphere. The method for producing a diamond sintered body according to claim 3, claim 9, claim 11, claim 22 or claim 23. 33. The remaining fibrous material having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more is SiC, TiC, B ₄ C, Si ₃ N ₄ ,
AlN, TiN, Al ₂ O ₃ , C, W, B, Mo, N
b, Ta, V, or Zr, having a minor axis of not more than 500 μm and a ratio of major axis to minor axis of 2
The fibrous substance having the above-mentioned shape is formed, claim 5, claim 5, claim 6, claim 7, claim 8, claim 9, claim 10, claim 11, and claim 24. The method for producing a diamond sintered body according to claim 25, claim 26 or claim 27. 34. A coated fibrous substance having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more in the remaining portion is B or T on the surface of the fibrous substance.
i, Zr, Hf, Ta, Nb, V, SiC, TiC, Z
rC, B ₄ C, WC, HfC, TaC, NbC, Si ₃
N ₄ , TiN, ZrN, AlN, HfN, TaN, Ti
B, TiB ₂ , ZrB ₂ , LaB ₆ , MoSi ₂ , B
A coated fibrous substance having a short diameter of 500 μm or less and a ratio of the long diameter to the short diameter of 2 or more, which is provided with a coating made of at least one of P and Al ₂ O _3. The method for producing a diamond sintered body according to claim 6, claim 7, claim 10, claim 11, claim 26 or claim 27. 35. A coated fibrous material having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more in the remaining part, wherein the fibrous material is in an oxidizing atmosphere,
Oxidation results in a coated fibrous substance having a minor axis of 500 μm or less and a ratio of the major axis to the minor axis of 2 or more, in which an oxide film is provided on the surface of the fibrous substance. The method for producing a diamond sintered body according to claim 6, claim 7, claim 10, claim 11, claim 26 or claim 27. 36. A method for manufacturing the diamond sintered body,
Claim 1, claim 2, claim 3, claim 4, claim 5, claim 6, characterized in that they are sintered under ultrahigh pressure of 2000 MPa or higher and high temperature in the thermodynamically stable region of diamond. Claim 7, Claim 8, Claim 9, Claim 10,
Claim 11, Claim 12, Claim 13, Claim 14, Claim 15, Claim 16, Claim 17, Claim 18, Claim 19, Claim 20, Claim 21, Claim 22, Claim. 23, claim 24, claim 25, claim 26, claim 2
7, claim 28, claim 29, claim 30, claim 3
1, claim 32, claim 33, claim 34 or claim 3
5. The method for producing a diamond sintered body according to item 5. 37. Claim 1, Claim 2, Claim 3, Claim 4, Claim 5, Claim 6, Claim 7, Claim 8, Claim 9, Claim 10, Claim 11, and Claim. Item 12, claim 1
3, claim 14, claim 15, claim 16, claim 1
7, claim 18, claim 19, claim 20, claim 2
1, claim 22, claim 23, claim 24, claim 2
5, claim 26, claim 27, claim 28, claim 2
9, claim 30, claim 31, claim 32, claim 3
3. A diamond sintered body manufactured by the method for manufacturing a diamond sintered body according to claim 3, claim 34, claim 35 or claim 36.