JPH1192852A - Intergranular metal dispersion strengthened wc-containing cemented carbide and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce intergranular metal dispersion strengthened cemented carbide improved in characteristics such as hardness, toughness, wear resistance, chipping resistance, impact-resistance or the like, at the time of precipitating tungsten carbide in the process of heating in a sintering stage, by dispersing fine and soft metals, alloys and intermetallic compds. into the tungsten carbide crystals and to provide a method for producing the same. SOLUTION: This intergranular metal dispersion strengthened cemented carbide contains, by volume, 3 to 40 vol.% bonding phases essentially consisting of iron base metal, <=50% (including zero) cubic system compds. of one or more kinds among the carbides, nitrides, carbonitrides, carboxides and carbon nitrooxides of the group 4a, 5a and 6a metals in the Periodic Table or their mutual solid solutions, and the balance tungsten carbide as essential components. In this case, the tungstent carbide contains intergranular dispersion strengthened tungsten carbide in which intergranular dispersing materials composed of metals, alloys and/or intermetallic compds. softer than the tungsten carbide are dispersed into the grains of the tungsten carbide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a WC-containing cemented carbide containing WC, in which fine particles of an intragranular dispersion comprising a metal, an alloy and / or an intermetallic compound are dispersed in crystal grains of tungsten carbide. Regarding the manufacturing method, specifically,
Residual stress is added to the tungsten carbide crystal grains by uniformly dispersing fine particles of a metal, alloy and / or intermetallic compound intragranular dispersion finer and softer than tungsten carbide in the tungsten carbide crystal grains. In addition, this soft intragranular dispersion suppresses the growth of fracture cracks, further improving the hardness, toughness, wear resistance, fracture resistance, plastic deformation resistance, heat crack resistance, etc. of the cemented carbide. Cutting tools such as inserts, drills and end mills for milling and turning, die tools such as dies and punches, cutting tools such as slitters, cutting tools,
Related to WC-containing cemented carbides with intragranular metal dispersion strengthening and optimized for wear-resistant tools and parts represented by nozzles and mechanical seals, or tools for civil engineering construction represented by various bits used for drilling and crushing, etc. It is.

[0002]

2. Description of the Related Art Generally, material properties such as hardness and toughness of a cemented carbide tend to have a trade-off that when one is improved, the other is reduced. There have been proposed a large number of cemented carbides containing platelet WC and methods for producing the same in order to simultaneously improve both properties of hardness and toughness. As typical prior art relating to the cemented carbide containing the platelet crystal WC, Japanese Patent Application Laid-Open Nos. 7-258785, 7-292426, and 7-3 by the present inventors.
No. 16688. In addition, although it is different from liquid phase sintering cemented carbide, it is a nanocomposite material in which ultrafine particles of other components are dispersed in matrix particles as a material that improves performance by simultaneously improving material properties. Many sintered bodies have been proposed. As typical prior arts of nanocomposite materials related to this ceramic sintered body, Japanese Patent Application Laid-Open Nos. Hei 2-229756, Hei 2-229775, Hei 6-116
No. 038 and JP-A-6-116072.

[0003]

Among prior arts relating to a typical cemented carbide having both improved hardness and toughness at the same time, Japanese Patent Application Laid-Open No. Hei 7-258785 discloses a hexagonal carbide contained in a cemented carbide. When the ratio of the (001) crystal plane to the (101) crystal plane in the X-ray diffraction of tungsten is 0.
A WC-containing cemented carbide comprising at least 50 platelets is disclosed. Also, Japanese Patent Application Laid-Open No. 7-292426 discloses that, when heating and sintering a powder of Co and / or Ni, a carbon source, and W, or a mixed powder of W and WC,
A first process in which a WC-based, Ni-WC-based, or Co-Ni-WC-based composite carbide is produced, and a second process in which plate-like crystals WC are produced by a reaction between the composite carbide and residual carbon. And a process for producing a platelet-shaped WC-containing cemented carbide comprising the steps of: Further, Japanese Patent Application Laid-Open No. 7-316638 discloses that Co and / or Ni powder, a carbon source, WC, 4a, 5a,
When heating and sintering a mixed powder of a Group 6a metal and an oxygen-containing compound, Co-WC, Ni-WC, Co-Ni
A method for producing a plate-like WC-containing cemented carbide including a first process in which a WC-based composite carbide is generated, and a second process in which a plate-like crystal WC is generated by a reaction between the composite carbide and residual carbon. Are listed. The plate-shaped WC-containing cemented carbide disclosed in these three publications has improved hardness and toughness as compared with conventional cemented carbide. However, the present inventors were not satisfied with these platelet WC-containing cemented carbides,
The object was to further improve the properties of the cemented carbide.

Among the typical prior arts having improved material properties, Japanese Patent Application Laid-Open Nos. 2-229756 and 2-2
Japanese Patent No. 29575 discloses that the characteristics of an alumina-based ceramics sintered body are improved by dispersing nanoparticles of titanium nitride or titanium carbide in crystal grains of alumina. Japanese Patent Application Laid-Open Nos. 6-116038 and 6-116072 disclose that silicon carbide nanoparticles are dispersed in silicon nitride crystal grains to improve the characteristics of a silicon nitride-silicon carbide ceramic sintered body. Is disclosed. The ceramic sintered bodies disclosed in these publications have improved characteristics as compared with conventional ceramic sintered bodies, but have poor toughness as compared with cemented carbides, making them impractical in the region where cemented carbides are used. There is.

The present invention has solved the above-mentioned problems. More specifically, the present invention relates to a plate-like WC-containing cemented carbide described in detail as the prior art and a superalloy obtained by a method for producing the same. Further improvement of hard alloys, mainly by distributing fine and soft metals, alloys and intermetallic compounds in tungsten carbide crystals during the selection of starting materials and the precipitation of tungsten carbide during heating in the sintering process The purpose of the present invention is to provide an intragranular metal dispersion strengthened cemented carbide having improved properties such as hardness, toughness, abrasion resistance, fracture resistance and impact resistance, and a method for producing the same.

[0006]

In a cemented carbide obtained by sintering a mixed powder of WC and Co, it is difficult to disperse fine particles of other components in the WC crystal. They have studied for a long time how to simultaneously improve the hardness and toughness of cemented carbides, and have found that W and Co represented by Co-W alloys, compounds, or Co-WC complex carbides, etc. When carbon powder is added to a starting material in which is uniformly dissolved as a solid and sintered, fine Co metal particles may be taken in and dispersed in WC crystals generated and grown in the sintering process. The inventors have found that a cemented carbide in which Co metal particles are uniformly dispersed in crystal particles is excellent in hardness, toughness, wear resistance, fracture resistance, impact resistance, and the like, and have completed the present invention. Things.

[0007] The cemented carbide containing WC with strengthened intragranular metal dispersion according to the present invention has a binder phase of 3 to 40% by volume containing iron group metal as a main component.
And at least 50% by volume of at least one cubic compound among carbides, nitrides, carbonitrides, carbonates, carbonitrides, and mutual solid solutions of metals belonging to groups 4a, 5a and 6a of the periodic table (Including 0) and the remainder being a cemented carbide containing tungsten carbide as a main component, wherein the tungsten carbide contains a softer metal, alloy and / or metal than the tungsten carbide in the tungsten carbide grains. It is characterized in that it contains intragranular dispersion-strengthened tungsten carbide in which an intragranular dispersion comprising an intermetallic compound is dispersed.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The binder phase in the cemented carbide according to the present invention is specifically Co, Ni, Co-Ni alloy, Fe-
Ni alloy and Co-W alloy, Co-Cr alloy, Co-Cr-W alloy, Ni-Cr alloy, Co-Ni-W-Cr alloy, Fe
-Ni-Co-W-Cr-Mo alloy as a typical example,
It consists of at least one selected from these. When the content of this binder phase with respect to the entire cemented carbide is less than 3% by volume, cavities remain in the cemented carbide and the strength, toughness, and fracture resistance are remarkably reduced, and conversely, it exceeds 40% by volume. When the amount increases, the hardness and abrasion resistance decrease remarkably, so the amount of the binder phase is set to 3 to 40% by volume.

The cubic compound phase in the cemented carbide according to the present invention is, specifically, TiC, TiN, ZrC, HfC,
TaC, NbC, VC, HfN, Ti (CN), Zr
(CN), (WTi) C, (WZr) C, (WTit
a) C, (WTiNbTa) C, (WTiTa) (C
N), (WZr) (C0), (WHf) C and the like as representative examples, and at least one selected from these. When the content of the cubic compound phase with respect to the entire cemented carbide exceeds 50% by volume, the content of the remaining tungsten carbide also relatively decreases, and the intragranular dispersion strengthening in the entire cemented carbide is increased. Since the content of tungsten carbide is also relatively small, the effect of improving strength and toughness is difficult to be exhibited.

[0010] The cemented carbide of the present invention substantially comprises the above-mentioned binder phase, the intragranular dispersion strengthened tungsten carbide and the conventional tungsten carbide, or the above-mentioned cubic compound phase. May be distributed.
Of these, the intragranular metal dispersion strengthened tungsten carbide is
In the conventional tungsten carbide, an intragranular dispersion made of a metal, an alloy, and / or an intermetallic compound which is softer than tungsten carbide is uniformly dispersed.

This intragranular dispersion is specifically made of Co, N
i, Fe, Ti, Zr, V, Hf, Nb, Ta, V, C
r, Mo, W, B, Si, Re, Os, Ir, Pt, P
Metals represented by d, Rh, and Ru, their alloys, Ti
Al, Ti ₃ Al, TiAl ₃ , NiAl, Ni ₃ Al,
NiAl ₃ , W ₆ Co ₇ , WCo ₃ , WNi ₄ , Fe ₃ W ₂ ,
Fe ₂ W, (TiNi) Al, (TiNi) ₃ Al, (T
INI) is made of at least one selected from among an intermetallic compound represented by Al _3.

Of these intragranular dispersions, Co, Ni,
Iron group metal of Fe, Co-Ni alloy, Co-W alloy, Ni
-Alloy containing iron group element represented by Cr alloy, NiA
1, Ni ₃ Al, NiAl ₃ , W ₆ Co ₇ , WCo ₃ , WN
i ₄ , Fe ₃ W ₂ , Fe ₂ W, (TiNi) Al, (TiN
i) ₃ Al, (TiNi) if composed of at least one selected from among an intermetallic compound containing iron group elements typified by Al ₃ is manufactured of grain dispersion strengthening tungsten carbide in the simple to the rate This is preferable because it is easy to adjust, and the effect of enhancing the strength, toughness, thermal crack resistance and thermal shock resistance of the obtained cemented carbide becomes remarkable.

This intragranular dispersion naturally consists of particles smaller than the particle size of the intragranular dispersion strengthened tungsten carbide.
When the average particle size exceeds 1.0 μm, WC
The average particle size of 1.0 μm or less is preferable because it is difficult to be incorporated into the crystal, and the average particle size is preferably 0.5 μm or less to further enhance the effect of improving the hardness and toughness by dispersion strengthening. is there. The relation between the particle size of the intragranular dispersion and the particle size of the intragranular dispersion-strengthened tungsten carbide is preferably such that the average particle size of the intragranular dispersion-strengthened tungsten carbide is at least three times the average diameter of the intragranular dispersion. In particular, when the ratio is 3 to 300 times, it is preferable because the effect can be further enhanced. Further, the content of the intragranular dispersion is preferably 0.005% by volume or more based on the whole tungsten carbide in order to exert the effect of the intragranular dispersion,
In order to further enhance the effect, the content is preferably 0.01% by volume or more.

The tungsten carbide in the cemented carbide according to the present invention is a WC crystal having a hexagonal structure, and among them, it is preferable that the shape of the intragranular dispersion strengthened tungsten carbide is a plate-like crystal. Intragranular dispersion-strengthened tungsten carbide made of plate-like crystals usually has the appearance of a triangular prism,
It is preferable to form a triangular or hexagonal plate-like crystal with a developed (001) plane, since the hardness and toughness are further improved at the same time. This intragranular dispersion strengthened tungsten carbide is
In order to enhance the effect of the intragranular dispersion, the content is preferably 20% by volume or more based on the entire cemented carbide.

The cemented carbide of the present invention, which has been described in detail above,
Similar to a conventional coated cemented carbide, a part or all of the surface can be coated with a conventional coating to be used as a coated cemented carbide. Specifically, the coating is made of a metal belonging to Group 4a, 5a, or 6a of the periodic table, carbides, nitrides, oxides of Al and Si, and their mutual solid solutions, diamond, diamond-like carbon, cubic boron nitride, and hard. Typical examples include a single layer or a laminate of two or more of boron nitride, a compound of carbon and nitrogen, and a compound of carbon, nitrogen and boron.

The cemented carbide according to the present invention is obtained by doping or ion-implanting an inorganic substance to be used as an intragranular dispersion into tungsten or tungsten carbide as a starting material, and using the doped or ion-implanted starting material. It is also conceivable to apply the method of manufacturing powder metallurgy described above. However, in such a method, the selection of the intragranular dispersion is limited, the process becomes complicated by the addition of the manufacturing process, and the manufacturing cost is increased. Therefore, the following manufacturing method of the present invention is preferable. is there.

The method for producing a cemented carbide according to the present invention comprises a first step of mixing and pulverizing starting materials for producing a cemented carbide to form a mixed powder, and molding the mixed powder into a powder compact. In a second step, a method for producing a cemented carbide in which the powder compact is heated and sintered at 1200 to 1600 ° C. in a non-oxidizing atmosphere or in a vacuum, the starting raw material contains W and an iron group element. A method characterized by containing one or both of an alloy powder and a composite carbide powder containing an iron group element, W and carbon, and a carbon source powder of carbon and / or graphite.

The first step and the second step in the manufacturing method of the present invention
The step and the third step can be performed by applying each step by a conventional method of manufacturing a cemented carbide and a conventional method of manufacturing a powder metallurgy. The starting material in this method is, specifically, a W-based alloy in which 1% by weight or more of iron group metal is dissolved, W ₆ Co ₇ , WCo ₃ , WNi ₄ , Fe ₃ W ₂ ,
W-containing alloy powders represented by intermetallic compounds such as Fe ₂ W, Co ₃ W ₉ C ₄ , Co ₂ W ₄ C, Co ₃ W ₃ C, Ni ₂ W ₄
At least one selected from the group consisting of C, FeW ₃ C, Fe ₄ W ₂ C, Fe ₆ W ₆ C and composite carbide powders represented by mutual solid solutions thereof, and a carbon source powder represented by carbon and / or graphite Is preferable because it is easy to uniformly disperse the intragranular dispersion of the iron group metal, and the binder phase can be formed at the same time.

The starting material in the production method of the present invention may be a second starting material containing W powder, iron group metal powder and carbon and / or graphite carbon source powder. This is preferable because the intragranular dispersion can be easily formed and the binder phase can be formed at the same time. However, in this case, it is important to form the first starting material during the heat sintering in the third step. These first and second starting materials include:
Further, a third material containing carbides, nitrides, carbonitrides, and their mutual solid solutions of elements of groups 4a, 5a, and 6a of the periodic table.
It is preferable that the starting material is used because a cubic compound can be formed in the cemented carbide.

As the other starting materials, it is preferable to use a binder phase precursor material which becomes a binder phase after sintering to form a binder phase, for example, cobalt oxide, nickel oxide or the like. In the case of a cemented carbide containing, the use of a metal or a hydride of the group 4a or 5a is preferable because of its excellent activation and the effect of increasing the reactivity.

[0021]

In the cemented carbide containing WC with strengthened intragranular metal dispersion according to the present invention, the intragranular dispersion softer than tungsten carbide is uniformly dispersed in the grains of tungsten carbide, so that the residual stress in the tungsten carbide grains is reduced. It has the effect of suppressing the propagation of cracks in the grains as well as reducing the defects of tungsten carbide that is recrystallized during sintering and the function of strengthening the grains of tungsten carbide. By uniformly dispersing the reinforced tungsten carbide in the cemented carbide, the cemented carbide acts to increase the hardness, strength, toughness, thermal crack resistance and thermal shock resistance of the cemented carbide. In addition, the method for producing a WC-containing cemented carbide with intragranular metal dispersion strengthening according to the present invention is a method for producing and growing fine intragranular dispersion particles added to a mixed powder of W, carbon and Co in a sintering process.
Being taken up and dispersed in the C crystal, the dispersed intragranular dispersion particles simultaneously improve the hardness and toughness of the WC crystal, and in particular, are uniformly dispersed in the cemented carbide to provide strength, toughness, It has the effect of significantly increasing the heat crack resistance and the thermal shock resistance.

[0022]

[Experimental test] First, a commercially available average particle size of 1.5
μm W, 1.2 μm Co, 1.7 μm Ni, 0.
Using each powder of 5 μm of Fe and 0.02 μm of carbon (denoted as “C” in the table), the mixture was weighed to the composition shown in Table 1, and inserted into a stainless steel pot together with an acetone solvent and a cemented carbide ball. After mixing and pulverizing for 24 hours, the mixed powder obtained by drying was inserted into a graphite crucible and subjected to an atmospheric pressure of 1%.
Heat treatment was performed at 1300 ° C. × 1 hour in a vacuum of Pa to obtain starting material powders M _{1 to} M ₇ of metals, alloys, and / or composite carbides. Starting material powders M _{1 to} M ₇ thus obtained
Table 1 also shows the approximate composition, carbon content, and average particle size of the sample by X-ray diffraction.

Next, the commercially available W, Co, Ni, Fe,
Carbon and the powders of M _{1 to} M ₇ prepared above, and commercially available WC having an average particle size of 2.5 μm, 4.5 μm
m of graphite (shown as “G” in the table), 1.7 μm of Cr
₃ C ₂ , 1.0 μm (WCi) C composite carbide (WC / TiC = 70/30 by weight ratio), and 1.0 μm TaC starting material powders were weighed to the composition shown in Table 2. Then, the mixture was inserted into a stainless steel pot together with an acetone solvent and a cemented carbide ball, mixed and pulverized for 48 hours, and dried to obtain a mixed powder. A mold is filled with these mixed powders, and 2to
Approximately 5.5 x 9.5 x 29 mm with a pressure of n / cm ²
Is prepared and placed on a sheet made of alumina and carbon fiber, and in a vacuum at an atmospheric pressure of 10 Pa,
By heating and holding at the temperatures shown in Table 2 for 1 hour, inventive products 1 to 7 and comparative products 1 to 7 were obtained.

The cemented carbides of the present invention products 1 to 7 and comparative products 1 to 7 thus obtained were wet-ground with a # 230 diamond grindstone to form a 4.0 × 8.0 × 25.0 mm shape. The bending force according to JIS standard was measured, and the results are shown in Table 3. After lapping one surface of the sample with a diamond paste of 0.3 μm, the hardness and fracture toughness K _1c at a load of 196 N using a Vickers indenter were measured.
(IM method) was measured, and the results are shown in Table 3. Further, the content of tungsten carbide, the binder phase, and the composition of other cubic compounds were determined and are shown in Table 3.

Then, a photograph of the structure of the wrapped surface of each of these samples was taken with an electron microscope, and the W
The material, particle size and volume ratio of the intragranular dispersion dispersed in the C crystal to the total WC were measured, and the results are shown in Table 4. Further, the average particle diameter of WC and the volume ratio of intragranular dispersed tungsten carbide (plate-like WC crystal having a longest diameter / shortest diameter of 3 or more) with respect to the entire cemented carbide were measured.

Next, using the mixed powder of the present invention 3 and the comparative product 3, the SP described in JIS-B4210 was used.
2 ton / cm with mold for GN120302 shape
^After the pressure press molding of No. ² , sintering was performed by the same method and conditions as described above. The obtained cemented carbide chip material was ground using a 230 # diamond grindstone, and SPGN120
308 cutting tips were produced.

Using this chip, a work material: SCM44
0, cutting speed: 100m / min, depth of cut: 2.0m
m, feed: 0.40 mm / tooth, cutting distance: 2 m, after performing a dry milling test, vertical cracks (vertical to the flank) and horizontal cracks (parallel to the flank) generated on the rake face of the blade edge ) Were measured and the depth in the cross section was measured, and the results are shown in Table 5. In addition, a test was performed under the above cutting conditions using three chips, and the maximum wear amount of the flank was 0.40.
mm, or the average cutting distance until chipping / breakage of the cutting edge was determined. The results are shown in Table 5.

Using a powder mixture prepared from the product 1 of the present invention and the comparative product 1, a powder isoform having a diameter of about 10 mm and a length of about 60 mm was formed by a dry isostatic pressing machine, and the blade was blanked. After that, it was heated and sintered under the same method and conditions as described above to obtain a super hard tip material for a gun drill. After the material chip thus obtained was brazed to a steel shank, it was wet-ground with a diamond grindstone to produce a gun drill having a tool diameter of 6.0 mm and a total length of 400 mm.

Using this gun drill, a workpiece: S4
5C, cutting speed: 90m / min, feed: 0.02mm
/ Rev, processing oil: water-soluble cutting oil, deep hole processing was performed, and the processing length until the corner wear of the cutting edge became 0.4 mm was determined. As a result, the product 1 of the present invention has a processing length of about 1
Compared to 0 m, Comparative Product 1 was 0.5 m due to significant chipping of the cutting edge.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Table 3]

[0033]

[Table 4]

[0034]

[Table 5]

[0035]

The WC cemented carbide with intragranular metal dispersion of the present invention has all of the transverse rupture strength, hardness and fracture toughness as compared with the conventional cemented carbide made of the same composition. It is excellent in strength, especially its strength, toughness, thermal crack resistance and thermal shock resistance are remarkably excellent. In addition, it is necessary to emphasize the strength, toughness, thermal crack resistance and thermal shock resistance, especially for milling and milling. When used as a rotary cutting tool typified by a gun drill, the tool life is significantly improved.

Claims (10)

[Claims] 1. A binder phase comprising 3 to 40 iron-group metals as a main component.
% By volume, and at least one cubic compound 50 among carbides, nitrides, carbonitrides, carbonates, carbonitrides, and mutual solid solutions of metals belonging to groups 4a, 5a and 6a of the periodic table.
When the content is equal to or less than the volume% (including 0), the balance is a cemented carbide containing tungsten carbide as a main component, and the tungsten carbide contains a metal, an alloy, and a softer than the tungsten carbide in the grains of the tungsten carbide. A WC-containing cemented carbide containing a strengthened intragranular metal dispersion, characterized by containing intragranular dispersion strengthened tungsten carbide in which an intragranular dispersion comprising an intermetallic compound is dispersed. 2. The intragranular metal dispersion strengthening according to claim 1, wherein the intragranular dispersion comprises an iron group metal, an alloy containing an iron group element, and / or an intermetallic compound containing an iron group element. WC-containing cemented carbide. 3. The intragranular dispersion has an average diameter of 0.5 μm.
The WC-containing cemented carbide containing WC according to claim 1 or 2, wherein the cemented carbide has a size of not more than m. 4. The WC-containing super-granular metal dispersion-enhanced dispersion according to claim 1, wherein the intragranular dispersion is dispersed in an amount of 0.005% by volume or more based on the whole of the tungsten carbide. Hard alloy. 5. The tungsten carbide for intragranular dispersion strengthening,
5. The WC according to claim 1, wherein the WC is made of plate-like crystal tungsten carbide.
Containing cemented carbide. 6. The tungsten carbide for intragranular dispersion strengthening,
The WC-containing cemented carbide containing WC according to any one of claims 1, 2, 3, 4 and 5, wherein the content is 20% by volume or more based on the whole cemented carbide. 7. A first step of mixing and pulverizing a starting material for producing a cemented carbide to form a mixed powder, a second step of molding the mixed powder to form a powder compact, The molded body is placed in a non-oxidizing atmosphere or in a vacuum at 1200 to 1600
And a third step of heating and sintering the alloy to a temperature of 0 ° C., wherein the starting material comprises W and an iron group element.
An intragranular metal comprising: one or both of an alloyed alloy powder and a composite carbide powder containing an iron group element, W and carbon; and a carbon source powder of carbon and / or graphite. Manufacturing method of dispersion strengthened WC containing cemented carbide. 8. A first step of mixing and pulverizing a starting material for producing a cemented carbide to form a mixed powder, a second step of molding the mixed powder to form a powder compact, The molded body is placed in a non-oxidizing atmosphere or in a vacuum at 1200 to 1600
And a third step of heating and sintering the alloy to a temperature of 0 ° C., wherein the starting material comprises W and an iron group element.
One or both powders of an alloyed alloy powder and a composite carbide powder containing an iron group element, W and carbon, a carbon source powder of carbon and / or graphite, and groups 4a, 5a and 6a of the periodic table A method for producing a WC-containing cemented carbide containing WC with at least one metal compound powder of metal carbides, nitrides, carbonitrides, and mutual solid solutions thereof. 9. A first step of mixing and pulverizing a starting material for producing a cemented carbide to form a mixed powder, a second step of molding the mixed powder to form a powder compact, The molded body is placed in a non-oxidizing atmosphere or in a vacuum at 1200 to 1600
A step of heating and sintering at a temperature of 300 ° C., wherein the starting material contains W powder, iron group metal powder, and a carbon source powder of carbon and / or graphite. A method for producing a WC-containing cemented carbide containing intragranular metal dispersion strengthened, characterized by the following: 10. A first step of mixing and pulverizing a starting material for producing a cemented carbide to form a mixed powder, a second step of forming the mixed powder into a powder compact, and the powder compact. 1200-1600 ° C. in a non-oxidizing atmosphere or vacuum
In the method for producing a cemented carbide which is heat-sintered, the starting materials are W powder, iron group metal powder, carbon source powder of carbon and / or graphite, and 4a, 5a, and 4a of the periodic table.
The WC-containing cemented carbide containing WC according to claim 9, which contains at least one metal compound powder of a carbide, nitride, carbonitride and a mutual solid solution of a Group 6a metal. Alloy manufacturing method.