KR20100088997A - Complete solid-solution powder for cemented carbide, cemented carbide and processes for preparing thereof - Google Patents

Abstract

The present invention relates to fully solid solution powders for cemented carbide production, cemented carbide, and methods for their preparation. More specifically, the present invention provides a solid solution powder for producing cemented carbide having a composition of (W _1-x M _x ) C or (W _1-x M _x ) (CN), wherein the metal (M) is represented by tungsten (T) on the periodic table of elements. Selected from Group 4 to Group 6 metals excluding W) and from solid solution powder for solid carbide production, rod or plate-like columnar phases, and from Groups 4 to 6 excluding tungsten (W) on the periodic table of elements, wherein 0 <x≤0.40. Cemented carbide comprising a metal phase (M) based solid phase carbide and a bonded phase combining the columnar phase with the minor phase, and a method of making them.

Description

Solid solution powder for cemented carbide production, cemented carbide sintered body and its manufacturing method {COMPLETE SOLID-SOLUTION POWDER FOR CEMENTED CARBIDE, CEMENTED CARBIDE AND PROCESSES FOR PREPARING THEREOF}

The present invention relates to fully solid solution powders for cemented carbide production, cemented carbide, and methods for their preparation. More specifically, the present invention provides a solid solution powder for producing cemented carbide having a composition of (W _1-x M _x ) C or (W _1-x M _x ) (CN), wherein the metal (M) is represented by tungsten (T) on the periodic table of elements. Cemented carbide solution for producing cemented carbide, rod or plate major phase, selected from Group 4 to Group 6 metals except W), Groups 4 to 6 except tungsten on the periodic table of the elements Cemented carbide comprising a minor phase of a metal (M) based solid solution carbide selected from the group and a binder phase combining the columnar phase with the minor phase, and a method of making them It is about.

The main cutting tools or wear resistant tools used in the metal cutting process required by the mechanical industry include WC-based cemented carbide, TiC or Ti (CN) -based cermet alloys, and other ceramic or high-speed steels.

Among them, the cemented carbide is composed mainly of a binding phase metal such as WC, Co, Ni, and Fe, and thus the IVa, Va, VIa group (Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W) metals in the periodic table. Refers to a sintered body of ceramic-metal composite powder containing carbide, nitride, and carbonitride as an additive.

In detail, the cemented carbide is hard ceramic powder such as TiC, TiN, Ti (CN), VC, Cr ₂ C ₃ , Mo ₂ C, NbC, TaC, WTiCN in addition to WC, and Co, Ni, Fe, etc., which are known phases for bonding them. Are prepared by mixing the metal powders and sintering them in a vacuum or hydrogen atmosphere.

The WC has a very high hardness (Vicker's hardness) of 2,100 kg / mm ² , a very high melting point of 3,050 K, and has excellent wear and corrosion resistance. Therefore, WC is used for cutting and die materials as a high-speed cutting tool material.

However, when the cemented carbide is manufactured using WC, which has superior toughness compared to other carbide and carbonitride tool materials, a binder phase metal such as Co is used as a liquid metal during sintering. In most cases, the shape of the equiaxed polyhedron is reduced because the wetting angle is small and the grain growth of the WC is mostly represented by the equiaxial growth of the faceted shape except when abnormal grain growth conditions are provided. Will be carried.

In terms of fracture mechanics, when designing high toughness materials, if rod-shaped or platelet-shaped materials with a high aspect ratio have a large fraction in the microstructure, Toughness can be remarkably increased compared to an equiaxial material. In other words, if an existing equiaxed WC can be replaced with a high aspect ratio rod or platelet shape WC, then if the crack progresses, the long WC particles can be rotated or the WC The cracks can continue to progress only if they are destroyed, resulting in a higher resistance to cracking. Higher toughness can be expected by using WC material of this shape. Therefore, many attempts have been made to obtain the microstructures by manufacturing rod-shaped or needle-shaped WCs and sintering with Co according to necessity. none.

Meanwhile, additive carbides such as TiC, TiN, Ti (CN), VC, Cr ₂ C ₃ , Mo ₂ C, NbC, TaC, and WTiCN have been used for improving the hardness within a given toughness range. Products in the form of WC-TiC-TiN-Co have been commercialized. Recently, when VC and Cr ₂ C ₃ are added to the nano-WC-Co to improve the hardness, the growth of the WC particles is controlled to obtain a remarkable hardness, but the relative toughness is reduced. Recently, efforts have been made to improve the toughness of cemented carbide using solid solution such as WTiCN.

In the present application, the oxides of the corresponding metal elements are mixed and pulverized according to the composition, and then reduced, carbonized, or carbonized to form a (W, M) C or (W, M) (CN) complete solid having a hexagonal closeness (hcp) structure. WC or (W, M) of hexagonal close structure is prepared by sintering a fully solid cemented carbide powder composed of and a small amount of face-centered cubic structure (M, W) C or (M, W) (CN) solid solution. The toughness of the conventional cemented carbide material is further increased by manufacturing a cemented carbide sintered body in which C is present as a main phase of 60% or more by volume fraction and whose shape is present in a rod shape or platelet shape.

Currently Treibach, H.C. Solid solution powders such as (W, Ti) (CN), which are marketed by Cermet composite sintered powder manufacturers such as Starck, are analyzed by XRD analysis and the microstructure of the sintered bodies. It appeared to be a microstructure with core / rim. It is estimated to be manufactured by mixing various carbonitrides for a long time at high temperature (1,700 ℃ ~ 2,200 ℃), and it is (W, M) C, (W, M) (CN) which is composed of full solid solution with hexagonal closest crystal structure. Solid solution powders such as (M = Group IVa, Group Va and Group VIa transition metals) have not been commercialized.

In the past, attempts to develop Ti-based cermets with improved toughness through the production of fully solid cermet composite sintered powders having no core structure have been carried out by metalworking tool companies such as Mitsubishi Corp. and Sumitomo Corp. of Japan. Has been made steady by.

For example, Japanese Patent Laid-Open No. 58-213619, filed by Nippon Shinkinzoku KK, and Japanese Patent Laid-Open No. 58-213842, filed by Mitsubishi (Method for Manufacturing High Strength Cermet, December 12, 1983) are solid solutions. It attempted to form but eventually produced a powder containing a partially solid solution with a core / rim structure. The sintered compact cermet obtained using this powder exhibited a conventional core / rim structure and did not show any characteristic different from that of other Ti-based carbides.

To still another prior art used as a starting material for preparing the cermet composite sintered body of a metal oxide USP 5,166,103 (1992.11.24) is the production of WC + TiC mixed powders (0.2μm to about 0.5μm) or a non-solid solution WC, WO _3, TiO ₂ and C are mixed to produce a cermet composite sintered compact powder using a vacuum rotary electric furnace at 1,200 ° C. to 2,000 ° C. (preferably 1,400 ° C. to 1,450 ° C.). However, this technique is reported to be a large amount of W ₂ C, W because the phase formation is not complete because it is a simple physical mixing process. Also no solid solution formation was reported.

In addition, Dow Chemical's USP 5,380,688 10 by at least mixing of one or more oxides and the carbon in the (Mehtod for making submicron meter carbides, submicron solid solution carbides, and the material resulting therefrom, 1995, 01.10) ² - to 10 ⁸ ℃ / sec Rapid heating discloses the preparation of WC single carbide and solid solution carbides of 0.01 μm to 1.0 μm size at 1,550 ° C. to 1,950 ° C. (Table 2).

Dow Chemical produced (W, Ti) C and (W, Mo) C of hcp structure containing a small amount of Ti or Mo by this method. The oxygen content was 2.7 wt% and 0.36 wt%, respectively. In addition, the variation of oxygen content was large according to each Example (Examples 3 and 4). Dow Chemical's patent also found that 5% to 20% by weight of WC and 30% to 40% by weight of W ₂ C, even for the manufacture of (W, Ta) C, (W, Ti, Ta) C Examples 10-11, 14, 15).

In combination with Examples 1 to 15 described in the Dow Chemical Patent and the results for the composite solid solution (Examples 16 to 37, Table 3), when a solid solution was made using two or more oxides through the manufacturing method of USP 5,380,688, 10 ^Since the solid solution was formed by rapidly raising the temperature to 2-10 ⁸ ° C / sec, it was mostly composed of a mixture of two partial solid solutions rather than a complete solid solution to form a solid solution.

These prior arts do not mention the preparation of carbonitride solid solution powders and the preparation of cermet powders including binding phases, and the grinding step is omitted as a process of mixing at 20 rpm in a jar lined with polyurethane.

In addition, Korean Patent Application No. 10-2003-0058941 filed by the Korea Institute of Science and Technology (for ultrafine grain cermet manufacturing method having a uniform solid solution particle structure, filed Aug. 26, 2003) and US Patent Publication US 2005/0047950 A1 According to (March 3, 2005), Ti, transition metal (TM), C, Ni and Co element powders are mixed and pulverized, and the (Ti, TM) C- of the face-centered cubic crystal structure, which is a solid solution of the material, is directly ground during the grinding process. While the method of manufacturing (Ni, Co) powder is disclosed, the method of manufacturing a sintered compact using the same is disclosed. For more information on this, see Mechanochemical synthesis of nanocomposite powder for ultra-fine (Ti, Mo) C-Ni cermet without core-rim strucutre, Int. J. Ref. Met. Hard Met., 22 (4-5), 2004 p193-196.

In addition to these prior arts, USP 5,166,103, US 6,793,875 and the like have a number of patents and a number of papers for the manufacture of carbides in a similar manner, but all of them are related to the preparation of carbide mixed powders that are not completely solid solutions.

General contents of the technique related to the production of solid solution powder are disclosed in Korean Patent Registration No. 10-0626224 (Solid powder, its preparation method, cermet powder including the solid solution powder, its preparation method and cermet using the cermet). This patent discloses a Ti-based fully solid solution of a face-centered cubic crystal structure, in which an oxide of the corresponding metal element is mixed (when using a nano-sized metal oxide) or mixed and pulverized to a relative temperature of 1000 ° C to 1300 ° C. A method of producing Ti-based fully solid solution carbides and carbonitrides of face-centered cubic crystal structure by reducing, carbonizing or nitriding at low temperatures is described.

Therefore, a method of preparing solid solution powder using a mixture of metal oxides pulverized with high energy as a starting material compared to the prior art in which various carbonitrides are mixed and heat treated at a high temperature (1,700 ° C to 2,200 ° C) for a long time to obtain an incomplete solid solution is a powder crystal grain. The small size, low process temperature, and simple manufacturing process also allow the phase separation during sintering through the composition adjustment to easily obtain a rod-shaped or plate-shaped WC solid solution having a large long ratio.

However, until now, the production technology of high quality WC solid solution powder which can be mass-produced commercially and easily control the amount of oxygen and carbon, and also the production technology of sintered body using such powder to optimize the production of cemented carbide for cutting tools It was never developed.

The basic object of the present invention is a solid solution powder for cemented carbide production having a composition of (W _1-x M _x ) C or (W _1-x M _x ) (CN), wherein metal (M) is represented by tungsten (W) on the periodic table of elements. It is to provide a complete solid solution powder for cemented carbide production, which is selected from Group 4 to Group 6 metals except 0, wherein 0 <x ≦ 0.40.

Still another object of the present invention is i) one or more materials selected from the group consisting of tungsten and tungsten oxide, one or more metals except for tungsten, oxides of these metals, and carbon powders of the metals of Groups 4 to 6 on the Periodic Table of the Elements. Mixing or mixing to grind; And ii) heating and reducing the carbonized mixture of step i), or reducing and carbonizing to provide a method for producing a solid solution powder for cemented carbide production.

Still another object of the present invention is a rod-shaped or plate-shaped columnar phase, an accessory phase of a metal (M) based solid solution carbide selected from Groups 4 to 6 except tungsten (W) in the periodic table of elements, and the columnar phase and the secondary phase It is to provide cemented carbide, including a bonded phase to bond the.

Still another object of the present invention is i) one or more materials selected from the group consisting of tungsten and tungsten oxide, one or more metals except for tungsten, oxides of these metals, and carbon powders of the metals of Groups 4 to 6 on the Periodic Table of the Elements. Mixing or mixing to grind; ii) reducing and carbonizing the mixture of step i) or reducing and carbonizing; And iii) to provide a cemented carbide manufacturing method comprising the step of sintering by mixing the binding phase metal to the powder obtained in step ii).

The basic object of the present invention described above is that in a solid solution powder for cemented carbide manufacturing having a composition of (W _{1 - x} M _x ) C or (W _{1 - x} M _x ) (CN), the metal (M) is represented by tungsten ( It can be achieved by providing a fully solid solution powder for cemented carbide production, selected from Groups 4 to 6 metals, except W), wherein 0 <x ≦ 0.40.

The complete solid solution powder is a single phase of (W, M) C or (W, M) (CN), or (W, M) C phase and (M, W) C phase or (W, M) (CN) phase And two phases of (M, W) (CN).

The M is preferably selected from Ti, V, Cr, Zr, Nb, Mo, Hf or Ta. In addition, the size of the fully solid solution powder is nanometer size or micrometer size.

Another object of the present invention described above is i) one or more materials selected from the group consisting of tungsten and tungsten oxide, one or more metals except tungsten and oxides of these metals in the metals of Groups 4 to 6 on the Periodic Table of the Elements, and Mixing or pulverizing the carbon powder; And ii) heating and reducing the carbonized mixture of step i), or reducing and carbonizing the mixture.

In the method for producing a fully solid solution powder for cemented carbide production of the present invention, at least one metal except for tungsten is preferably selected from Ti, V, Cr, Zr, Nb, Mo, Hf or Ta.

In the grinding process, a device such as a high energy ball mill may be used. The grinding process may be performed according to the size of the prepared raw powder. In addition, the size of the powder obtained in step i) is nanometer size or micrometer size.

In the method for producing a fully solid solution powder for cemented carbide production of the present invention, the heating temperature of step ii) is preferably 800 ° C to 1,600 ° C, more preferably 1,100 ° C to 1,500 ° C. In addition, the heating time of step ii) is preferably 5 minutes to 3 hours.

The complete solid solution powder prepared by the method for preparing solid solution powder for cemented carbide according to the present invention may be a single phase of (W, M) C or (W, M) (CN), or a (W, M) C phase and (M, W It may consist of two phases: a) C phase or (W, M) (CN) phase and (M, W) (CN) phase.

Another object of the present invention described above is a rod or plate-shaped columnar phase, an elementary phase of metal (M) based solid solution carbide selected from Groups 4 to 6 except tungsten (W) in the periodic table of elements, and the columnar phase and the It can be achieved by providing cemented carbide, including a bonding phase that binds the accessory phases.

In the cemented carbide of the present invention, it is preferable that the main phase contains 60% by volume to 95% by volume. In addition, the columnar phase is a hexagonal close structure (hcp) WC phase or WC and a small amount of M solid solution phase, the aspect ratio of the columnar phase (aspect ratio) is preferably 4: 1 to 30: 1, the length of the columnar phase It is preferable that it is 0.1 micrometer-50 micrometers.

In comparison, the accessory phase is (M, W) C of the face centered cubic structure fcc. The main phase and the accessory phase M are preferably selected from Ti, V, Cr, Zr, Nb, Mo, Hf or Ta.

The bonding phase of the cemented carbide of the present invention is preferably selected from the group consisting of Co, Ni, Fe and alloys thereof.

In addition, the accessory phase is an additive selected from the group consisting of carbides, nitrides and carbonitrides of metals selected from Groups 4 to 6 except W on the periodic table of elements (for example, TiC, TiN, Ti (CN), ZrC, MoC, Mo ₂ C, Cr ₂ C ₃ , VC, etc.) may be further included, and the additive is preferably contained in the cemented carbide 0.1 to 20% by weight.

Another object of the present invention described above is i) one or more materials selected from the group consisting of tungsten and tungsten oxide, one or more metals except tungsten and oxides of these metals in the metals of Groups 4 to 6 on the Periodic Table of the Elements, and Mixing or pulverizing the carbon powder; ii) reducing and carbonizing the mixture of step i) or reducing and carbonizing; And iii) it can be achieved by providing a cemented carbide production method comprising the step of sintering by mixing the binding phase metal to the powder obtained in step ii).

The size of the powder obtained in step i) of the cemented carbide production process of the present invention is nanometer size or micrometer size.

The heating temperature of step ii) of the cemented carbide production method of the present invention is preferably 800 ° C to 1,600 ° C, more preferably 1,100 ° C to 1,500 ° C. In addition, the heating time of step ii) is preferably 5 minutes to 3 hours.

The powder obtained in step ii) is a single phase of (W, M) C or (W, M) (CN), or (W, M) C and (M, W) C phase or (W, M) ( CN) phase and (M, W) (CN) phase.

Sintering of step iii) is preferably carried out for 5 minutes to 1 hour in the temperature range of 1,200 ℃ to 1,600 ℃. Moreover, it is preferable to heat at the temperature increase rate of 1 degree-C / min-20 degree-C / min to the said sintering temperature.

In the cemented carbide production method of the present invention, an additive selected from the group consisting of carbides, nitrides and carbonitrides of metals selected from Groups 4 to 6 except tungsten (W) in the mixture of step i) For example, TiC, Ti (CN), TiN, TaC, NbC, etc.) may be further included. The additive is preferably contained in 0.1 to 20% by weight of the mixture of step i).

According to the present invention, physical properties such as toughness and strength can be greatly improved by forming a rod-like or plate-like dispersed phase in the microstructure of the sintered body through phase separation or particle growth from a completely solid solution phase. Therefore, it is possible to replace the conventional WC-Co cemented carbide material including the conventional equiaxed angular WC dispersed phase to enable the production of high strength and high toughness cutting tools.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following description of the embodiments is only intended to specifically describe the specific embodiments of the present invention, it is not intended to limit or limit the scope of the present invention to the contents described therein.

Example  One.

WO ₃ , TiO ₂ and carbon powders were prepared to prepare (W _{1 - x} Ti _x ) C fully solid carbide powders. The mixture of materials thus prepared was ground using a WC-Co ball dry for 20 hours under conditions of 250 rpm and a ball-to-powder ratio (BPR) of 30: 1 using a high energy planetary mill. Solid solution carbide powders were prepared by heat treatment at 1,300 ° C. or 1,500 ° C. for 2 hours under vacuum, followed by reduction and carbonization. In addition, (W _{1 - x} Ti _x ) C-10wt% Co cermet powder prepared by mixing the (W _{1 - x} Ti _x ) C solid solution and Co prepared to prepare a cermet in a vacuum furnace for 1 hour at 1,450 ℃ Sintering was carried out to prepare a sintered body.

A 1 is produced at 1,300 ℃ reduction for 2 hours, the carbide _{(a) (W 0 .95 Ti} 0 .05) C, (b) (W 0 .90 Ti 0 .10) C, (c) (W _{0 .85} Ti _{0 .15)} is a SEM photograph of the C, and _{(d) (W 0 .80 Ti} 0 .20) the microstructure of the powder C.

FIG. 2 shows sintered bodies ((a) obtained by mixing (W _{1 - x} Ti _x ) C solid solution powder prepared by reducing and carbonizing at 1,300 ° C for 2 hours with Co and sintering in a vacuum furnace at 1,450 ° C for 1 hour. _{W 0 .95 Ti 0 .05) C} -10Co, (b) (W 0 .90 Ti 0 .10) C-10Co, (c) (W 0 .85 Ti 0 .15) C-10Co and (d) SEM image of the microstructure of (W _0.80 Ti _0.20 ) C-10Co).

The sintered body sintered from the powder mainly consisted of WC or WC solid solution in the form of rod or plate, having an aspect ratio of 4: 1 to 30: 1 and most of the phases having a length of 5 μm or more.

3 is reduced from 1,500 ℃ for 2 hours, which was prepared by carbonization _{(a) (W 0 .95 Ti} 0 .05) C, (b) (W 0 .90 Ti 0 .10) C, (c) (W _{0 .85} Ti _{0 .15)} is a SEM photograph of the C, and _{(d) (W 0 .80 Ti} 0 .20) the microstructure of the powder C.

FIG. 4 shows (a) (W _0.95 Ti) obtained by sintering in a vacuum furnace at 1,450 ° C. by mixing Co with (W _{1 - x} Ti _x ) C solid solution powder prepared by reducing and carbonizing at 1,500 ° C. for 2 hours. _{0.05) C-10Co, (b} ) (W 0 .90 Ti 0 .10) C-10Co, (c) (W 0 .85 Ti 0 .15) C-10Co and _{(d) (W 0.80 Ti 0.20} ) C SEM picture of the microstructure of -10Co (Co in wt%) sintered bodies.

The (W _{1 - x} Ti _x ) C solid solution powder prepared by reduction and carbonization at 1,500 ° C. for 2 hours was not much different from the powder produced at 1,300 ° C. However, in the sintered body sintered from the powder produced at 1,500 ° C, the plate-shaped WC or WC solid solution mainly made the cross section. The long width ratio decreased compared to FIG. 2, and as the amount of Ti in solid solution increased, the amount of hcp WC solid solution (white plate / rod) decreased and the amount of fcc (Ti, W) C solid solution (gray background) increased.

The W, WO _3, TiO ₂ and carbon powder in order to produce the above (W _{0 .90 0 .10} Ti) C solid solution carbide powder was completely ready. At this time, W and WO ₃ were maintained at a weight ratio of 1: 1. The mixture of materials thus prepared was ground using a WC-Co ball dry for 20 hours under conditions of 250 rpm and a ball-to-powder ratio (BPR) of 30: 1 using a high energy planetary mill. Solid solution carbide powder was prepared by heat treatment at 1,300 ° C. under vacuum for 2 hours to undergo reduction and carbonization. In addition, for one hour at 1,450 ℃ by molding the (W _{0 .90} Ti _{0 .10)} the (W _{0 .90} Ti _{0 .10)} cermet powder, a mixture of C solid solution with Co to prepare the Preparation C-10wt% Co cermet Was sintered in a vacuum furnace to prepare a sintered body. In the case where the powder was prepared by mixing W together, the results were similar to those of FIGS. 1 and 2.

Example  2.

WO ₃ , TiO ₂ , and carbon powders were prepared to prepare (W _{1 - x} Ti _x ) C fully solid carbide powders. The mixture of materials thus prepared was ground using a high energy planetary mill at 250 rpm and a BPR (Ball-to-Powder Ratio) 30: 1 for 20 hours, dry using WC-Co balls, and then at 1,000 ° C. under vacuum. A solid solution carbide powder was prepared by heat treatment at 1,100 ° C. for 2 hours to undergo reduction and carbonization, and the phase separation of (W _{1 - x} Ti _x ) C on the XRD (001) plane was investigated.

Figure 5 is a pulverized mixture of WO _3, TiO _2, C powder according to the second embodiment of the present invention, and prepared by carbonizing for 2 hours at a vacuum of 1,000 ℃ reduction _{(a) (W 0 .95 Ti} 0 .05 ) for _{C, (b) (W 0.90} Ti 0.10) C, (c) (W 0 .85 Ti 0 .15) C and _{(d) (W 0 .80 Ti} 0 .20) X -ray diffraction analysis of the powder C It is a graph showing the results of phase analysis.

Figure 6 is in accordance with the second embodiment of the present invention, WO _3, TiO _2, a mixture of C powder was pulverized, and prepared by carbonizing reduction for 2 hours at a vacuum of 1,100 ℃ _{(a) (W 0 .95 Ti} 0 .05 ) for _{C, (b) (W 0.90} Ti 0.10) C, (c) (W 0 .85 Ti 0 .15) C and _{(d) (W 0 .80 Ti} 0 .20) X -ray diffraction analysis of the powder C It is a graph showing the results of phase analysis.

In 1,000 ℃ start (Ti, W) peak (peak) C on the employment of the fcc structure is separated from the _{(W 0 .9 Ti 0 .1)} C employing a hcp crystal structure, and that this peak moves to increasingly elevation Show a tendency. However, the 1,100 ℃ (W _{0 .8} Ti _{0 .2)} from C of the fcc structure (Ti, W) C begins to peak separation. This shows that as the reduction carbonization temperature is raised, more Ti atoms can be substituted and dissolved in the WC, resulting in more Ti added at 1,100 ° C than 1,000 ° C and later phase separation.

Example  3.

_{(W 1 - x Ti x)} WO 3, TiO 2, Co 3 O 4, and to prepare a carbon powder in order to produce a complete solid-solution powder, the cermet having C-6wt% Co composition. The mixture of materials thus prepared was ground using a planetary mill at 250 rpm and ball-to-powder ratio (BPR) for 30 hours dry using a WC-Co ball for 20 hours and then under vacuum at 1,000 ° C. or 1,100 ° C. Heat treatment was performed for 2 hours at, followed by reduction and carbonization. Manufactured by the above method _{(W 0.95 Ti 0.05) C-} 6Co, (W 0 .90 Ti 0 .10) C-6Co, (W 0 .85 Ti 0 .15) C-6Co and (W _{0 .80} Ti _{0 .20),} a sintered body was manufactured by sintering in a vacuum furnace for molding a solid-solution C-6Co cermet powder for 1 hour at 1,510 ℃.

Figure 7 according to the third embodiment of the present invention, _{WO 3, TiO 2, Co 3} O 4, mixing the pulverized powder C, and a reduced production for two hours at a vacuum of 1,000 ℃ by carbonization (a) (W _{0 .95 Ti 0 .05) C-6Co,} (b) (W 0.90 Ti 0.10) C-6Co, (c) (W 0 .85 Ti 0 .15) C-6Co and _{(d) (W 0 .80 Ti} 0. ₂₀ ) Graph showing the results of phase analysis by X-ray diffraction analysis of C-6Co (Co in wt%) powder.

Figure 8 according to the third embodiment of the present invention, _{WO 3, TiO 2, Co 3} O 4, a mixture of C powder was pulverized and prepared by carbonizing reduction for 2 hours at a vacuum of 1,100 ℃ (a) (W _{0 .95 Ti 0 .05) C-6Co,} (b) (W 0.90 Ti 0.10) C-6Co, (c) (W 0 .85 Ti 0 .15) C-6Co and _{(d) (W 0 .80 Ti} 0. ₂₀ ) is a graph showing the results of phase analysis by X-ray diffraction analysis of C-6Co powder.

XRD results of the powders synthesized at 1,000 ° C. and 1,100 ° C. showed (W, Ti) C solid-state phase, eta phase due to Co and carbon deficiency. This shows that a large amount of carbon is required when reducing at low temperatures.

Example  4.

(W _{1 - x} Ti _x) was prepared WO _3, TiO _2, and the carbon powder to C-6 ~ 10wt% Me producing a complete solid-solution powder, the cermet having (Me = Co or Ni) composition. The mixture thus prepared was ground under the same conditions as in the above examples, and then heat-treated under vacuum at 1,100 ° C. or 1,300 ° C. for 2 hours to form a solid solution carbide through reduction and carbonization, and mixed with an appropriate amount of Ni or Co. The solid solution cermet powder of (W _{1 - x} Ti _x ) C-ywt% Me (Me = Co, Ni) composition prepared by the above method was molded and sintered in a vacuum furnace at 1,450 ° C or 1,510 ° C for 1 hour. Prepared.

9 is reduced from 1,100 ℃ for 2 hours, one hour vacuum sintered at 1,510 ℃ using a solid solution carbide produced by carbonizing _{(a) (W 0 .95 Ti} 0 .05) C-6Co, (b) (W to _{0 .90 Ti 0 .10) C-} 6Co, (c) (W 0 .85 Ti 0 .15) C- 6Co and _{(d) (W 0 .80 Ti} 0 .20) of the microstructure of sintered bodies C-6Co For SEM picture.

FIG. 10 shows (a) (W) prepared by mixing and molding (W _{1 - x} Ti _x ) C powders prepared by reduction carbonization at 1,300 ° C. for 2 hours with Co and sintering in a vacuum furnace at 1,450 ° C. for 1 hour. _{0.95 Ti 0.05) C-10Co,} (b) (W 0 .90 Ti 0 .10) C-10Co, (c) (W 0 .85 Ti 0 .15) C-10Co and (d) (W _{0 .80} Ti _{0 .20)} is a SEM photo of the microstructure of sintered bodies C-10Co.

FIG. 11 shows (a) (W) prepared by mixing and shaping (W _{1 - x} Ti _x ) C powders prepared by reduction carbonization at 1,300 ° C. for 2 hours with Co and sintering in a vacuum furnace at 1,450 ° C. for 1 hour. _{0.95 Ti 0.05) C-10Co,} (b) (W 0 .90 Ti 0 .10) C-10Co, (c) (W 0 .85 Ti 0 .15) C-10Co and (d) (W _0.80 Ti _0.20 SEM image showing fracture section of C-10Co sintered body.

A 12 is at 1,300 ℃ reduction for 2 hours, a vacuum carbide sintered for one hour at 1,450 ℃ using a solid solution carbide prepared by _{(a) (W 0 .95 Ti} 0 .05) C-10Ni, (b) ( _{W 0.90 Ti 0.10) C-10Ni} , (c) (SEM photograph of the _{W 0 .85 Ti 0 .15) C} -10Ni and _{(d) (W 0 .80 Ti} 0 .20) the microstructure of the sintered bodies C-10Ni to be.

The results show that the shape of the hcp (W, Ti) C solid solution can vary greatly depending on the amount of Co in the bonding phase. Show that you have In the case of using Ni as a binding phase, it was not so different from that of Co.

FIG. 13 is an XRD result of (W _{1 - x} Ti _x ) C solid solution carbide (x = 0.05 to 0.4) prepared by reducing and carbonizing at 1,300 ° C. for 2 hours.

Significant separation of (Ti, W) C solid solution of fcc structure from (W, Ti) C solid solution powder of hcp crystal structure began to appear from x = 0.2 ~ 0.25 around 2θ = 36 °. W) the (W _{0 .90} C exists on the employment Ti _{0 .10)} were found from C, i.e. x = 0.1 composition. Compared with FIG. 6, it can be seen that the presence of the bonded phase and the high temperature sintering increase the solubility of Ti in the solid solution.

14 is at 1,300 ℃ reduction for 2 hours, one hour vacuum sintered at 1,450 ℃ using a solid solution carbide produced by carbonizing _{(W 0 .90 Ti 0 .10)} C-10Co ((a) and (b)) SEM images of the microstructures of (W _0.90 Ti _0.10 ) C-20Co ((c) and (d)) and typical WC-10Co ((e) and (f)) sinters. 14 (b), (d) and (f) show the progress of indentation cracks made for toughness measurement in the sintered body. In Figure 14 (b) and (d) it can be seen that the long grown WC effectively prevents the progress of cracking.

Table 1 and the _{(W 0 .90 Ti 0 .10)} C-10Co and (W _{0 .90} Ti _{0 .10)} commercial WC-10Co as a result of measuring the toughness and hardness of C-20Co used in Example 4 Compared. It can be seen that the presence of rod-shaped or plate-shaped WC or WC solid solution significantly improves toughness.

Hardness (H _v , GPa) Toughness (K _IC , MPa · m ^1/2 ) WC-10Co (ref) 13 ± 0.7 13 ± 0.8 _{(W 0 .90 Ti 0 .10)} C-10Co 12 ± 0.4 15 ± 0.9 _{(W 0 .90 Ti 0 .10)} C-20Co 12 ± 0.5 21 ± 0.7

Example  5.

WO ₃ , Nb ₂ O ₅ , MoO, V ₂ O ₅ , ZrO _{2 ,} TiO to prepare various (W _{1 - x} M _x ) C (M = Nb, Zr, Mo, V, Ti) fully solid carbide powders ₂ , and carbon powder was prepared according to the composition. The mixture thus prepared was ground under the same conditions as the above examples, and then heat-treated at 1,100 ° C., 1,300 ° C., or 1,500 ° C. for 2 hours to prepare a solid solution carbide through reduction and carbonization. A (W _{1- x} M _x ) C-10wt% Co solid solution cermet powder prepared by mixing an appropriate amount of Co was molded and sintered in a vacuum furnace at 1,450 ° C. for 1 hour to prepare a sintered body.

FIG. 15 is prepared by mixing and grinding WO ₃ , Nb ₂ O ₅ , MoO, V ₂ O ₅ , ZrO ₂ , and carbon powder according to Example 5 of the present invention and reducing carbonization in a vacuum furnace at 1,300 ° C. for 2 hours. (a) (W _{0 .95 0 .05} M) C and _{(b) (W 0 .90 M} 0 .10) C powder phase analysis by X-ray diffraction analysis of a (M = Nb, Zr, Mo , V) A graph showing the results.

FIG. 16 is prepared by mixing and grinding WO ₃ , Nb ₂ O ₅ , MoO, V ₂ O ₅ , ZrO ₂ , and carbon powder according to Example 5 of the present invention and reducing carbonization for 2 hours in a vacuum furnace at 1,500 ° C. FIG. (a) (W _{0 .95 0 .05} M) C and _{(b) (W 0 .90 M} 0 .10) C powder phase analysis by X-ray diffraction analysis of a (M = Nb, Zr, Mo , V) A graph showing the results.

Powders employing Nb, V, Mo, and Zr prepared by reduction carbonization at 1,300 ° C for 2 hours had a secondary phase of W ₂ C due to lack of carbon regardless of the amount and type of additives, and Nb and Zr were added. case, (Zr, W) C and (Nb, W) C employing different _{(W 0 .95 M 0 .05)} C, (W 0.90 M 0.10) were observed in both the C composition. Powders prepared by reduction carbonization at 1,500 ° C. for 2 hours did not contain W ₂ C regardless of the type of added element when the amount of the additive was 5 mol%. This is because less carbon was used in high temperature reduction. In the case of the addition amount of 10 mol%, W ₂ C was not present in all the solid solutions except (W, V) C. However, when Nb and Zr were added, the (Nb, W) C and (Zr, W) C solid solution phases of the fcc crystal structure were separated and precipitated from the (W, M) C solid solution phase of the hcp crystal structure.

17 is according to the fifth embodiment of the present invention, WO _3, TiO _2, and mixed by pulverizing the carbon powder manufactured 1,100 ℃, 1,300 ℃ or from 1,500 ℃ reduction for 2 hours to carbonization in a vacuum (a) (W _{0. 90} Ti _{0 .10)} C and _{(b) (W 0 .80 Ti} 0 .20) is a graph showing a phase analysis by X-ray diffraction analysis of the powder C.

Is to be reduced with increasing the carbonization temperature reduction is easy without the use of carbon when the Ti is employed in a solid solution did not exist, _{W 2 C, (W 0 .90} Ti 0 .10) C and (W _{0 .80} Ti _{0 In} both _.20 ) _Cs , the WC solid solution was the main phase, with some (Ti, W) C solid phases present as shown in FIG. 13.

FIG. 18 is a pulverized mixture of WO ₃ , Nb ₂ O ₅ , MoO, V ₂ O ₅ , ZrO ₂ , and carbon powder in accordance with Example 5 of the present invention, according to the composition, and in a vacuum furnace of 1,300 ° C. time to reduction carbide is mixed with a prepared (W _{0 .95 0 .05} M) C powder (M = Nb, Zr, Mo , V) Co and molding are manufactured by sintering for 1 hour at 1,450 ℃ in a vacuum furnace ( _{a) (W 0 .95 V 0} .05) c-10wt% Co, (b) (W 0 .95 Mo 0 .05) c-10wt% Co, (c) (W 0 .95 Zr 0 .05) a SEM photograph of the C-10wt% Co, and _{(d) (W 0 .95 Nb} 0 .05) microstructure of C-10wt% Co sintered body.

The results show that the particle shape can vary greatly depending on the type of solid solution added, and that even when V is used, rod- or plate-shaped WC solid solution phases can be produced.

Hardness (H _v , GPa) Toughness (K _IC , MPam ^1/2 ) Porosity WC-10Co (ref.) 13.0 ± 0.7 13.0 ± 0.8 A2B1 _{(W 0 .95 V 0 .05)} C-10Co 15.0 ± 0.5 10.0 ± 0.9 A2B1 _{(W 0 .95 Mo 0 .05)} C-10Co 13.6 ± 0.4 10.9 ± 0.1 A3B2 _{(W 0 .95 Zr 0 .05)} C-10Co 12.3 ± 0.5 12.6 ± 0.7 A2B1 _{(W 0 .95 Nb 0 .05)} C-10Co 14.8 ± 0.7 9.5 ± 1 A1B1

Table 2 shows the hardness, toughness and porosity of cermet using WC solid solution powders of various compositions, and compared with general WC-Co. All the sintered bodies showed excellent porosity and physical properties.

A 1 is prepared by reduction at 1,300 ℃ for two hours, carbonized in the first embodiment of the present invention _{(a) (W 0 .95 Ti} 0 .05) C, (b) (W 0 .90 Ti 0 .10) _{C, (c) (W 0} .85 Ti 0 .15) is a SEM photograph of the C, and _{(d) (W 0 .80 Ti} 0 .20) the microstructure of the powder C.

2 is obtained by mixing (W _{1 - x} Ti _x ) C solid solution powder prepared by reduction and carbonization at 1,300 ℃ for 2 hours in Example 1 of the present invention by mixing with Co in a vacuum furnace for 1 hour at 1,450 ℃ Sintered bodies ((a) (W _0.95 Ti _0.05 ) C-10Co, (b) (W _0.90 Ti _0.10 ) C-10Co, (c) (W _0.85 Ti _0.15 ) C-10Co and (d) (W _0.80 Ti _0.20 SEM image of the microstructure of C-10Co).

A 3 is prepared from 1,500 ℃ reduction for two hours, carbonized in the first embodiment of the present invention _{(a) (W 0 .95 Ti} 0 .05) C, (b) (W 0 .90 Ti 0 .10) _{C, (c) (W 0} .85 Ti 0 .15) is a SEM photograph of the C, and _{(d) (W 0 .80 Ti} 0 .20) the microstructure of the powder C.

4 is obtained by mixing (W _{1 - x} Ti _x ) C solid solution powder prepared by reduction and carbonization at 1,500 ℃ for 2 hours in Example 1 of the present invention by mixing with Co at 1,450 ℃ for 1 hour in a vacuum furnace _{(a) (W 0.95 Ti 0.05} ) c-10Co, (b) (W 0.90 Ti 0.10) c-10Co, (c) (W 0.85 Ti 0.15) c-10Co and _{(d) (W 0 .80 Ti} 0. ₂₀ ) SEM picture of the microstructure of C-10Co (Co in wt%) sintered bodies.

5 is manufactured WO _3, TiO _2, mixed powder C was pulverized, and reduced for 2 hours at a vacuum of 1,000 ℃ by carbonization in the second embodiment of the present invention _{(a) (W 0 .95 Ti} 0 .05) C, (b) (W _0.90 Ti _0.10 ) C, (c) (W _0.85 Ti _0.15 ) C and (d) (W _0.80 Ti _0.20 ) C is a graph showing the results of phase analysis by X-ray diffraction analysis.

Figure 6 is a manufacturing WO _3, TiO _2, mixed powder C was pulverized, and reduced for 2 hours at a vacuum of 1,100 ℃ by carbonization in the second embodiment of the present invention _{(a) (W 0 .95 Ti} 0 .05) C, (b) (W _0.90 Ti _0.10 ) C, (c) (W _0.85 Ti _0.15 ) C and (d) (W _0.80 Ti _0.20 ) C is a graph showing the results of phase analysis by X-ray diffraction analysis.

7 is prepared by mixing and grinding WO ₃ , TiO ₂ , Co ₃ O ₄ , C powder in Example 3 of the present invention and reducing carbonization for 2 hours in a vacuum furnace at 1,000 ° C. (W _0.95 Ti _0.05 ) C-6Co, (b) (W _0.90 Ti _0.10 ) C-6Co, (c) (W _0.85 Ti _0.15 ) C-6Co and (d) (W _0.80 Ti _0.20 ) C-6Co (Co in wt%) powder It is a graph showing the results of phase analysis by X-ray diffraction analysis.

In Figure 8, a third embodiment of the present invention, _{WO 3, TiO 2, Co 3} O 4, a mixture of C powder was pulverized and prepared by carbonizing reduction for 2 hours at a vacuum of 1,100 ℃ (a) (W _{0 .95} Ti _X -ray of _{0 .05} ) C-6Co, (b) (W _0.90 Ti _0.10 ) C-6Co, (c) (W _0.85 Ti _0.15 ) C-6Co and (d) (W _0.80 Ti _0.20 ) C-6Co powder It is a graph showing the results of phase analysis by diffraction analysis.

9 is reduced for 2 hours at 1,100 ℃ in Example 4 of the present invention, the carbonized using the viscous solid solution carbide for one hour vacuum sintered at _{1,510 ℃ (a) (W 0} .95 Ti 0 .05) C- _{6Co, (b) (W 0} .90 Ti 0 .10) C-6Co, (c) (W 0.85 Ti 0.15) C- 6Co and _{(d) (W 0.80 Ti 0.20} ) on the microstructure of sintered bodies C-6Co SEM picture.

10 is (W _{1 - x} Ti _x ) C powder prepared by Coding with reduced carbon at 1,300 ℃ for 2 hours in a vacuum furnace in Example 4 of the present invention by mixing with Co and shaping at 1,450 ℃ for 1 hour in a vacuum furnace (A) (W _0.95 Ti _0.05 ) C-10Co, (b) (W _0.90 Ti _0.10 ) C-10Co, (c) (W _0.85 Ti _0.15 ) C-10Co and (d) (W _0.80 Ti _0.20 ) SEM picture of the microstructure of the C-10Co sintered bodies.

11 is (W _{1 - x} Ti _x ) C powder prepared by Co 2 in the vacuum furnace 1,300 ℃ 2 hours reduced carbon in Example 4 of the present invention by mixing and molding with Co and sintered in a vacuum furnace for 1 hour at 1,450 ℃ (A) (W _0.95 Ti _0.05 ) C-10Co, (b) (W _0.90 Ti _0.10 ) C-10Co, (c) (W _0.85 Ti _0.15 ) C-10Co and (d) (W _0.80 Ti _0.20 ) SEM image showing fracture section of C-10Co sintered body.

12 is (a) (W _0.95 Ti _0.05 ) C-10Ni, (s) vacuum-sintered at 1,450 ° C. for 1 hour using a solid solution carbide prepared by reducing and carbonizing at 1,300 ° C. for 2 hours in Example 4 of the present invention. b) SEM image of the microstructure of (W _0.90 Ti _0.10 ) C-10Ni, (c) (W _0.85 Ti _0.15 ) C-10Ni and (d) (W _0.80 Ti _0.20 ) C-10Ni sintered body.

FIG. 13 is an XRD result of (W _{1 - x} Ti _x ) C solid solution carbide (x = 0.05 to 0.4) prepared by reducing and carbonizing at 1,300 ° C. for 2 hours in Example 4 of the present invention.

Figure 14 is a 10Co-C reduction for one hour vacuum sintered at 1,450 ℃ using a solid solution carbide produced by carbonizing (W _{0 .90} Ti _{0 .10)} for 2 hours at 1,300 ℃ in Example 4 of the present invention (( SEM pictures of the microstructures of a) and (b)), (W _0.90 Ti _0.10 ) C-20Co ((c) and (d)) and sinters of general WC-10Co ((e) and (f)).

15 is prepared by mixing and grinding WO ₃ , Nb ₂ O ₅ , MoO, V ₂ O ₅ , ZrO ₂ , and carbon powder in Example 5 of the present invention and reduced carbonization for 2 hours in a vacuum furnace at 1,300 ° C. ( a) (W _0.95 M _0.05 ) C and (b) (W _0.90 M _0.10 ) C A graph showing the results of phase analysis by X-ray diffraction analysis of powders (M = Nb, Zr, Mo, V).

16 is prepared by mixing and grinding WO ₃ , Nb ₂ O ₅ , MoO, V ₂ O ₅ , ZrO ₂ , and carbon powder in Example 5 of the present invention and reduced carbonization in a vacuum furnace at 1,500 ° C. for 2 hours ( a) (W _0.95 M _0.05 ) C and (b) (W _0.90 M _0.10 ) C A graph showing the results of phase analysis by X-ray diffraction analysis of powders (M = Nb, Zr, Mo, V).

FIG. 17 shows (a) (W _0.90 Ti _0.10 ) prepared by mixing and grinding WO ₃ , TiO ₂ , and carbon powder in Example 5 of the present invention, and reducing carbonization at 1,100 ° C., 1,300 ° C., or 1,500 ° C. for 2 hours. A graph showing the results of phase analysis by X-ray diffraction analysis of (C) and (b) (W _0.80 Ti _0.20 ) C powders.

FIG. 18 is a pulverized mixture of WO ₃ , Nb ₂ O ₅ , MoO, V ₂ O ₅ , ZrO ₂ , and carbon powder according to the composition in Example 5 of the present invention, and a vacuum furnace at 1,300 ° C. for 2 hours. reducing the hydrocarbon prepared by (W _{0 .95 0 .05} M) C powder (M = Nb, Zr, Mo , V) and the Co were mixed and molded to prepare by sintering in a vacuum furnace for one hour at 1,450 ℃ (a _{) (W 0 .95 V 0 .05} ) C-10wt% Co, (b) (W 0.95 Mo 0.05) C-10wt% Co, (c) (W 0 .95 Zr 0 .05) C-10wt% Co and _{(d) (W 0 .95 Nb} 0 .05) is a SEM photo of the microstructure of the C-10wt% Co sintered body.

Claims (30)

In a solid solution powder for solid carbide production having a composition of (W _1-x M _x ) C or (W _1-x M _x ) (CN), the metal (M) is in Groups 4 to 6 except tungsten (W) on the periodic table of elements. A solid solution powder for cemented carbide production, selected from group metals, wherein 0 <x ≦ 0.40. The method of claim 1 wherein the fully solid solution powder is a single phase of (W, M) C or (W, M) (CN), or (W, M) C phase and (M, W) C phase or (W, A solid solution powder for cemented carbide production, characterized by consisting of two phases, M) (CN) and (M, W) (CN). The solid solution powder for preparing cemented carbide according to claim 1, wherein M is selected from the group consisting of Ti, V, Cr, Zr, Nb, Mo, Hf and Ta. i) one or more materials selected from the group consisting of tungsten and tungsten oxide, one or more metals except tungsten, oxides of these metals, and carbon powders of the metals of Groups 4 to 6 on the periodic table step; And ii) reducing and carbonizing the mixture of step i), or reducing and carbonizing the mixture. The method of claim 4, wherein at least one metal except tungsten is selected from the group consisting of Ti, V, Cr, Zr, Nb, Mo, Hf and Ta. 5. The method of claim 4, wherein the heating temperature of step ii) is 800 ° C to 1,600 ° C. 5. The method of claim 4, wherein the heating temperature of step ii) is 1,100 ° C to 1,500 ° C. 5. The method of claim 4, wherein the heating time of step ii) is 5 minutes to 3 hours. The method of claim 4, wherein the fully solid solution powder is a single phase of (W, M) C or (W, M) (CN), or (W, M) C phase and (M, W) C phase or (W, Method for producing a fully solid solution powder for cemented carbide production, characterized in that it consists of two phases (M) (CN) and (M, W) (CN). A rod-like or plate-shaped columnar phase, an elementary phase of a metal (M) based solid-solution carbide selected from Groups 4 to 6 except tungsten (W) in the periodic table of elements, and a bonding phase combining the columnar phase with the minor phase Cemented carbide. The cemented carbide according to claim 10, wherein the columnar phase contains from 60% to 95% by volume. The carbide according to claim 10, wherein the M is selected from the group consisting of Ti, V, Cr, Zr, Nb, Mo, Hf and Ta. The cemented carbide according to claim 10, wherein the columnar phase is a hexagonal-tungsten tungsten carbide (WC) phase or a solid solution phase of tungsten carbide (WC) and a small amount of M. The cemented carbide of claim 10, wherein the columnar aspect ratio is 4: 1 to 30: 1. The cemented carbide of claim 10, wherein the columnar has a length of 0.1 μm to 50 μm. The cemented carbide according to claim 10, wherein the accessory phase is (M, W) C having a face centered cubic structure. The carbide according to claim 10, wherein the bonding phase is selected from the group consisting of Co, Ni, Fe and alloys thereof. The cemented carbide according to claim 10, wherein the bonded phase is 0.1 wt% to 50 wt% of the cemented carbide. The method of claim 10, wherein the accessory phase is characterized in that it further comprises an additive selected from the group consisting of carbides, nitrides and carbonitrides of the metal selected from Groups 4 to 6 except tungsten (W) in the periodic table of the elements Carbide. 20. The carbide according to claim 19, wherein the additive is contained in the cemented carbide in an amount of 0.1 wt% to 20 wt%. i) one or more materials selected from the group consisting of tungsten and tungsten oxide, one or more metals except tungsten, oxides of these metals, and carbon powders of the metals of Groups 4 to 6 on the periodic table step; ii) reducing and carbonizing the mixture of step i) or reducing and carbonizing; And iii) mixing the sintered metal with the powder obtained in step ii) and sintering the cemented carbide manufacturing method. The method of claim 21, wherein the at least one metal except tungsten is selected from the group consisting of Ti, V, Cr, Zr, Nb, Mo, Hf and Ta. The method of claim 21, wherein the heating temperature of step ii) is a carbide production method, characterized in that 800 ℃ to 1,600 ℃. The method of claim 21, wherein the heating temperature of step ii) is a cemented carbide production method, characterized in that 1,100 ℃ to 1,500 ℃. The method of claim 21, wherein the heating time of step ii) is carbide production method, characterized in that 5 minutes to 3 hours. The method of claim 21, wherein the powder obtained in step ii) is a single phase of (W, M) C or (W, M) (CN), or (W, M) C phase and (M, W) C phase or A method of manufacturing a cemented carbide sintered body comprising two phases (W, M) (CN) and (M, W) (CN). 22. The method according to claim 21, wherein the sintering of step iii) is performed for 5 minutes to 1 hour at a temperature range of 1,200 ° C to 1,600 ° C. 22. The method according to claim 21, wherein the sintering of step iii) is carried out under a vacuum of 0.1 Torr to 100 Torr in a nitrogen atmosphere. 22. The method of claim 21, wherein in step i), an additive selected from the group consisting of carbides, nitrides and carbonitrides of metals selected from Groups 4 to 6 except tungsten (W) on the periodic table of elements is further mixed. Carbide manufacturing method to use. The method of claim 29, wherein the additive is a cemented carbide production method, characterized in that contained in the mixture of step i) 0.1% to 20% by weight.

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