WO1992002651A1

WO1992002651A1 - Hard alloy

Info

Publication number: WO1992002651A1
Application number: PCT/JP1990/000966
Authority: WO
Inventors: Hiroshi Izumi; Yukimichi Kakuma
Original assignee: Nippon Carbide Kogyo Kabushiki Kaisha
Priority date: 1989-03-17
Filing date: 1990-07-30
Publication date: 1992-02-20
Also published as: JPH02243735A

Abstract

A titanium-base hard alloy containing titanium, tungsten, molybdenum, vanadium, niobium, tantalum, nickel, cobalt, carbon, and nitrogen as the essential ingredients each in a specified proportion, wherein at least 80 atomic % in total of titanium, tungsten, molybdenum, vanadium, niobium, and tantalum are present in the form of carbides, nitrides and/or carbonitrides. This alloy has high hardness and excellent toughness and is suited for use in making various tools, especially cutting tools which are required to have sharp tool angles, such as a twist drill or an end mill.

Description

Harm

Hard alloy

Technical field

Honoki is a new hard alloy. More specifically, it has excellent hardness and toughness. In particular, titanium carbide that can be machined into cutting tools such as drills and end mills that require a sharp edge angle, The present invention relates to a tough superhard alloy based on nitride and / or carbonitride.

Background art

Hard alloys based on titanium carbides, nitrides, and carbonitrides (hereinafter abbreviated as “TiC-based alloys” for the sake of simplicity) have been replaced by conventional WC-based alloys. It is lighter in weight, has higher hardness, has better oxidation resistance, has less chemical affinity with other metals, and is used in some parts such as bytes.

However, TiC-based alloys are generally inferior in toughness and poor in secondary workability, such as sharp cutting edges with a small cutting edge angle, so that they are used for tools with relatively large cutting edges such as bytes. However, it was very difficult to use it for drills with a small edge angle and especially for small drills. To improve the toughness of the TiC base alloy, one of the metals such as M0, W, Nb, Ta, Cr, V, Zr, Hf, etc. It has often been proposed to add two or more types of carbides or nitrides [for example, Japanese Patent Publication No. 52-9403, Japanese Patent Publication No. 55-14856, Japanese Patent Publication No. 55-40998, Japanese Patent Publication No. No. 56-32384 and Japanese Patent Publication No. 56-32386].

Although the toughness deficiency is improved to some extent by these conventional TiC-based alloys, the toughness is not large enough to be satisfactory, and the cutting edge is It is difficult to machine a sharp cutting tool, such as a drill, and it is difficult to machine a drill with a small blade diameter and high precision. Even if it can be added, it can be used practically Then, it was broken or chipped in a short time, and it was not enough as a cutting tool. The present inventors have conducted intensive studies to develop a high-toughness TiC-based alloy that has solved the above-mentioned disadvantages, and as a result, have completed the present invention. Disclosure of the invention

Thus, according to the present invention, Ti ゝ W, Mo, V, Nb, Ta, Ni, Co, C and N are contained as essential components; Ti, W, Mo, At least 80 at.% Of the sum of V, Nb and Ta is present in the form of carbides, nitrides and Z or carbonitrides; the content of each of the above elements is based on the weight i of the hard alloy, Ti 24 to 45%, W 4 to 28%, Mo 2 to 5%, V 0.1 to 2.5%, Nb 2 to 20%, Ta 2 to 20%, Ni 5.7 to 37.9%, and Co 7.1 to 39.3%; the sum of Nb and Ta is 4 to 23%, and the weight ratio of Ta / Nb is in the range of 0.9 to 3.5. The content of the sum of Ni and Co (Ni + C0 :) is 20 to 45% and the weight ratio of Ni / Co is in the range of 0.4 to 1.8; And the weight ratio of Nip: child (C atom + N atom) is in the range of 0.30 -0.60, and (the total amount of C atom and N atom) Z (the above metal urine except Ni and Co) Hard alloy is provided atomic ratio of the total amount) and Toku徵 to be within the range of 0.8 to 1.0.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 is a side view of the straight shank drill, where H indicates the torsion angle and A indicates the tip angle (135 degrees). Fig. 2 is an enlarged view of the cutting edge of the straight shank drill shown in Fig. 1. In the figure, P indicates the single-step clearance angle, S indicates the two-step clearance angle, and (90-P) indicates the blade angle. It is.

FIG. 3 is a side view of the tip portion of the cutter. FIG. 4 is a plan view of the cutting edge portion of the power cutter of FIG. 3, in which indicates the cutting edge angle.

Embodiment of the Invention

The hard alloy of the present invention is composed of 10 kinds of elements of Ti, W, Mo, V, Nb, Ta, Ni, Co, C and N as essential components. The content ratio of these constituent elements can be in the range shown in the following table in terms of metal based on the weight of the final hard alloy. However, the inside of the katsuki shows a suitable range.

Metal component content (%)

T i 24-45 (28-40, especially 30-35) W 4-28 (6-25, especially 10-20) 'Mo 2-15 (3-12, especially 5-8)

V 0.1 -2.5 (0.2 ~ 2.0, especially 0.3 ~ 0)

N b 2 ~ 20 (3 ~ 17, especially 5 ~ 15) T a 2 ~ 20 (3 ~ 17, especially 5 ~ 15)

(N b + T a) 4 to 23 (7 to 20, especially 10 to 17)

T a / N b (weight ratio) 0.9-3.5 (1.0 to 2.5, especially 1.2

~ 2.0)

N i 5.7 ~ 37.9 (7.0 ~ 30, especially 8.0

~ 20) C o 7.1 to 39.3 (8.0 to 35, especially 9.0

-20)

(N i + Co) 20-45 (20-35, especially 20-30)

N i / C o (weight ratio) 0.4 to 1.8 (0.6 to 1.5, especially 0.8 to

B 1.2)

Of the above constituent elements, most of Ti, W, Mo, V, Nb and Ta, that is, at least 80 atomic%, preferably 85 atomic% or more of the total of these metallic elements, particularly 90 atomic% % Or more is contained in the hard alloy in the form of carbides, nitrides and Z or carbonitrides, and Nb is present substantially in the form of carbides, and Ta is substantially in the form of nitrides. Desirably it exists in a state.

It is important that the respective amounts of C atoms and N atoms derived from carbides, nitrides, and carbon or carbonitrides in the hard alloy of the present invention are mutually balanced, and N atoms / (. Atoms + The weight ratio of (1 ^ atoms) should be in the range of 0.30 to 0.60. If it is out of this range, it will be difficult to obtain a high toughness alloy intended by the present invention. Thus, the preferred range of the weight ratio of N atom Z (C atom + N atom) is 0.33 to 0.50, and more preferably 0.35 to 0.45. Therefore, the carbides, nitrides, and Z or carbonitrides of the metal elements constituting the hard alloy of the present invention are selected so that the weight ratio of N atoms Z (C atoms + N atoms) falls within the above range. It is important to control those combinations.

Further, in the hard alloy of the present invention, the balance between the total amount of C atoms and N atoms and the total amount of metal waste excluding Ni and Co is also important, and (the total amount of C atoms and N atoms). / (Total amount of metal atoms excluding Ni and C0) It is desirable that the atomic ratio be in the range of 0.8 to 1.0, preferably 0.82 to 0.98, and particularly 0.85 to 0.96. It is difficult to get Incidentally, the hard alloy of the present invention, in addition to the metal components mentioned above, also in inevitable impurities brought in accompanying the manufacture raw _s fee in the alloy C r and F e, etc. contain trace No problem.

The hard alloy of the present invention described above generally comprises, as starting materials, nitrides, nitrides and / or carbonitrides of the metal components Ti, W, Mo, V, Nb and Ta, and N It can be manufactured by using i and Co metal in the desired composition ratio for the final alloy product and subjecting it to compounding, grinding, mixing, drying, forming, sintering, etc. in a manner known per se. it can.

Some of the metal components Ti, W, Mo, V, Nb and Ta can also be used in the form of a simple metal. : Should not exceed 20 at.% Of the sum of these metal components and should preferably be less than 15 at.%, In particular less than 10 at. If decarburization or denitrification is likely to occur during the sintering process, it is desirable not to use a force that further reduces the amount of metal added as a single metal.

If at least a part of Mo is used in the form of a simple metal, a hard alloy having particularly excellent physical properties can be produced, which is preferable.

Thus, starting materials particularly suitable for producing the hard alloys of the present invention require the elements Ti, W, Mo, V, Nb, Ta, Ni, Co, C and N. These components are contained in the above-mentioned ratios, and each metal component of Ti, W, V, Nb and Ta is substantially present in the form of carbide, nitride and carbon or carbonitride. Mo is at least partially metal simple and the rest is carbide, Ni and Co are present in the form of a raw powder substantially as a simple metal, and in particular, Nb is substantially in the form of a carbide, and Conveniently, Ta is used in a substantially nitrided state.

First, in the compounding step, generally, the starting material is compounded with a binder and a dispersion medium. Examples of the binder include camphor, paraffin, liquid paraffin, and high molecular compounds (eg, polyvinyl butyral, polyacrylic acid ester, etc.). Examples of the dispersion medium include methyl alcohol, ethyl alcohol, and the like. Organic solvents such as acetone, toluene, xylene, and methyl acetate are included. The amount of the binder and the dispersing medium is usually in the range of 20 to 70% by weight, preferably 40 to 60% by weight, respectively, based on the starting materials.

The above formulation is then ground and mixed. This pulverization and mixing can be carried out using a pulverizer such as a pole mill, attritor, vibrating mill, or the like. It is desirable to keep it below 5 microns.

The uniform dispersion formulation thus obtained is then dried to remove the dispersion medium. Drying can be carried out according to a conventional method using a dryer such as a spray drier, a Herschel mixer, or a vacuum drier, whereby the content of the dispersion medium is reduced to about 0.01% by weight or less. It is preferable to do it. For example, as an example of drying conditions when drying is performed in a vacuum dryer, the temperature is 10 to 80 ° C, preferably 30 to 60 ° C, and the degree of vacuum is ¹⁰ to 11 to 1. 0 " ⁸ mmHg, time: 0.1 to 3 hours.

The dispersion formulation thus dried is then processed by a molding machine to the desired Into a molded product having a shape suitable for the intended use. As a molding machine, a press molding machine such as a rubberless machine or a powder press machine is mainly used, and in some cases, an extrusion molding machine or an injection molding machine can also be used. In the case of molding by extrusion molding or injection molding, it is also possible to appropriately add a plasticizer, a solvent and the like in order to enhance the fluidity of the compound. When molding in the compression molding machine, the molding pressure etc. but blending composition, generally, 0 .5 ~ 2 .0 t / on preferably appropriately within the range of 1 ~ 1 .5 t Zcm ² I think that the. Others, edited by Hisashi Suzuki, “Cemented Carbide and Sintered Hard Materials—Basics and Applications,” pp. 309-372 (published by Maruzen Co., Ltd. on February 20, 1986); Editing Committee Lecture Sub-Committee “Ceramics Manufacturing Process-Powder Adjustment and Forming-” pp. 214-219 (published by the Japan Ceramics Association) Yoichi Motoki, “Ceramics Manufacturing Process I”, pp. 239-241 (1980, October 10 Θ First edition, published by Gihodo Shuppan Co., Ltd.) The method is also applicable.

The molded product obtained as described above is fired in a vacuum or in an inert gas atmosphere. Generally 1 0-1 0 as vacuum that can be applied when the - ⁵ marrow H g, preferably about 1 0 _ ² to 1 0 - is appropriately within a range of ^{3 niniH} g, also an inert gas Examples thereof include argon, helium, and nitrogen. The sintering conditions can be changed over a wide range according to the raw material composition, the shape of the molded product, the molding conditions, and the like. Is usually about 1200 to about 170 ° C., particularly about 130 to about 160 ° C. The range of C is appropriate, and the firing time is about 0.1 to 3 hours, particularly about 0.5 to 1 hour. By firing as described above, the intended hard alloy of the present invention is obtained. This hard alloy can be made into a final product suitable for each application by cutting, polishing, and finishing with a diamond wheel or the like into a shape suitable for each application.

For example, the hard alloy provided by the present invention can be suitably used as a material for cutting tools, particularly cutting tools requiring hardness and toughness. Conventionally, a cutting tool made of a TiC-based alloy has been used only for a part of the pipe because of its inferior toughness despite having excellent cutting characteristics as described above. In addition, many proposals have been made to cover the surface of a tough cutting tool with a TiC-based alloy as a method of utilizing the cutting characteristics while supplementing the low toughness of the TiC-based alloy (for example, No. 6 1-501 034, Japanese Unexamined Patent Publication No. 60-162782, Japanese Unexamined Patent Publication No. 61-96072, Japanese Unexamined Patent Application Publication No. 61-2321 / 175, Japanese Unexamined Patent Publication No. 61-24 No. 7673, Japanese Patent Publication No. 62-44572 and Japanese Patent Application Laid-Open No. 62-93376).

However, a cutting tool having a sharp cutting angle made of a C-based alloy, particularly a cutting tool, has not yet been proposed.

In this specification, the term “cutting tool” includes the cutting tools described in “JIS Handbook Tools” published on April 12, 1988 (1st edition, 1st edition), edited by the Japan Standards Association. Includes pite, drill, milling machine, reamer, hobbing tool, broach, threading tool, Hacksaw and its frames, machinery

■ r

Examples thereof include cutting tools, and preferred are bytes, drills, and milling cutters. Knits are tools with cutting edges at the end of the shank or body used for lathes, boring machines, planing machines, shaping machines, vertical milling machines, etc. Depending on the structure of the machine, solid bytes, bladed pipes, welding bytes, filters There are a brazing byte, a clamp byte, a throwaway byte, an insertion byte, an assembly byte, and the like, and the hard alloy of the present invention includes, among others, a peeling byte, a cutting byte, a clamp byte, and a thrower. It is particularly suitable for processing into wavy bytes.

A drill is a tool mainly used for drilling, which has a cutting edge at the tip and a groove for discharging chips into the body. Or, depending on the application, there are luma type drill, core drill, shell drill, center hole drill, square hole drill, dish drill, target drill, gun drill, blade drill, etc., but the hard alloy of the present invention is In particular, it can be advantageously used for a luma type drill, a core drill, and a speed drill.

Milling cutters are also called milling cutters, which have a cutting edge on the outer peripheral surface, end surface or side surface, and are tools for rotary cutting, and are mainly used for milling machines. Depending on the function or application, there are two types: a pore type milling cutter and a shank type milling cutter. Examples of pore type mills include flat mills, slab cutters, side mills, single edge mills, union mills, face mills, shell end mills, groove mills, sit mills, metal saws and cold saws. , Segment saw, angle milling, single-sided milling, non-conformal milling, conformal milling, secondary milling, inner round milling, outer round milling, single-sided milling, double-sided milling , Impulse milling, sprocket milling, slab milling, serration milling, thread milling, and general milling.The hard alloy of the present invention is particularly suitable for flat mills and shell end mills. It is preferably used. On the other hand, for shank tie milling mills ^ For example, end mills, single-flute end mills, two-flute end mills, three-flute end mills, multi-flute end minoles, double-ended end minoles, tapered end mills, ponoré end mills, tapered pole end mills, and radius end dominoles , Square end mill, 緣 -shaped end mill, High helix end mill, For semi-finishing

5 End mill, roughing end mill, keyway end mill, gear cutting end mill, counterbore milling machine, flat screw sinking mill, countersunk screw sinking mill, hexagon socket bolt sinking mill, chamfering mill , A chamfering mill, a grooved milling cutter, a crisp smash cutter, a T-slot milling machine, a half-moon keyway milling machine, a honey mill, and the like.

Used as a component material for 10-mm, single-flute end mills, 2-flute end mills, 3-flute end mills, multi-flute end mills, pole end milles, square iron dominoles, and high-helix end mills In particular, it exhibits excellent performance. As described above, the hard alloy of the present invention has high toughness in addition to high hardness, so that if the hard alloy of the present invention is used, the cutting edge angle is 4 is 0 to 170 degrees. There is an excellent feature that a cutting tool having a sharp edge angle of preferably 45 to 90 degrees, more preferably 50 to 70 degrees can be easily machined. Here, the “edge angle” of the cutting tool is the angle of the edge of the cutting edge formed by the rake face and the flank face [for example, in the drill shown in FIG. The step clearance angle) is the zero angle of the cutting edge.]

Cutting tools obtained by using the hard alloy of the present invention, such as drills and end mills, are not only suitable for processing metals having high hardness, but also are suitable for processing relatively soft metals such as aluminum and copper. It turned out to be a good effect. In particular, this trend is due to the recently developed 30,000-80,000 rpm high-speed processing machine. This is remarkable when used as a tool.

Further, the hard alloy of the present invention can be processed into a cutting tool other than a cutting tool. Other blades other than cutting tools are listed in “Blue Books, Blade Trivia Dictionary, Illustration 'All of Blades”, published by Kobunsha Co., Ltd., the first press, August 20, 1986, by Hidefumi Tachibana. Cutting tools other than the cutting tools used are included, and specific examples thereof include cutting tools of the Kanna group, kitchen knife group, saw group, scissors group, file group and whetstone group, and cutting tools for cutting soil. The knife of the Kanna tribe is a knife having a function of cutting straight, and includes, for example, a canna, an axe, a flea, a nata, a razor, a chisel, a pencil sharpener, and the like. The hard alloy of the present invention can be suitably used for pencil sharpening and the like, especially for force razors. The knife of the kitchen knife family is a knife having a function of cutting by applying a pushing force, for example, a knife, a rotary knife, a knife, a knife and a cutter, and the present invention is preferably applied to a knife, a knife and a cutter. Can be used advantageously. The saw blade is a blade having a function of cutting with a number of aligned teeth, and includes, for example, a saw, a circular saw, a saw blade knife, and a chainsaw. A saw blade knife 7 is preferable. The cutting blades of the scissors are cutting blades having a function that can be held between blades, and the hard alloys of the present invention include, for example, scissors, clippers, razors, lawn mowers, shears, punches, pliers, snacks, wire cutting, cutting, and the like. It is preferably used as a material for at least the blade portion of scissors, razors and pliers. File-type knives are knives in which stubborn blades are aligned, specifically, files, graters, sandpaper, slivers, holes, knives sharpeners and croakers. Can advantageously utilize the hard alloys of the present invention in files and knife sharpeners. Whetstone-type blades are hard particles The hard alloy of the present invention can be applied to a paper file, a grinder, a fiber cleaner, a metal brush, or the like, preferably a grinder. The blade that cuts the soil is a blade that has the function of cutting soil, sand, and rocks, and is used for agriculture, horticulture, civil engineering, and mining. And a rock drill, etc., but the hard alloy according to the present invention exerts an excellent ability particularly for a rock drill.

As described above, since the hard alloy of the present invention has high toughness in addition to high hardness, it can be processed into a cutting tool other than the cutting tool as described above.

There is a unique feature that conventional hard alloys do not have, such as 10 ability.

However, when the hard alloy of the present invention is used, a cutting edge having a sharp edge of 10 to 40 degrees, preferably 12 to 35 degrees, more preferably 15 to 30 degrees is used. It can be processed into blades other than tools. Here, the term "cutting edge angle" for a cutting tool other than the cutting tool refers to the angle of the tip cutting edge formed by the rake face and the flank face, and specifically, for example, is indicated by in the cutter shown in FIG. Angle.

As described above, the hard alloy of the present invention can be machined into a blade with a sharp edge, and the blade using the hard alloy of the present invention has very little chipping of the blade and wear of the blade. There are various excellent advantages such as very little and little welding to metal during use.

Example

Hereinafter, the present invention will be described more specifically with reference to examples.

Examples 1-21 and Comparative Examples 1-9

A .—Preparation of hard alloy As the raw material powder, a sintered body of TiC and TiN having an average particle size of 1 ^ (TiCZ 11 ^ _: 50/50, hereinafter referred to as TiCN), 2〃 WC powder, 3 Mo ₂ C and Mo powders, 2-3 ^ VC powders, 2-3 NbC and NbN powders, 1-2; «TaC and TaN powders, 4 Ni powders and 2 C 0 powders were mixed as shown in Table 1, and these powders were mixed with ethyl alcohol 50% i% \ polyvinyl butyral double: ft% and dioctyl lid as a plasticizer. Then, 1% by weight of a rate (DOP) was added, and the mixture was pulverized and mixed with a stainless steel pole mill for 48 hours. However, only TiCN of hard alloy No. 20 (Example 20) in Table 1 was used, and TiCZTiN was set to 70/30.

Subsequently, the mixture obtained by drying under reduced pressure was pressure-molded at 1 T0 nZcm ² by a rubber bubbling machine. The molded body 300 to 500 ° C, 1 hour, binder removal one under the conditions of vacuum degree 1 0 one ² mmHg, further 1 360-1 50 0, 1 hour, a vacuum of 1 0 one ^{3 irnnH} g It was fired under the conditions to prepare a rod-shaped hard alloy (6 mm X 30 mm).

B. Evaluation of hard alloy

Table 2 shows the toughness and hardness of the obtained alloy. The methods for measuring physical properties are as follows.

(1) Measurement of brittleness

Three-point bending strength measurement according to JISB-4104.

(2) Hardness measurement

Measured by Shimadzu Micro Hardness Tester N036739.

As is clear from Table 2, the hard alloy of the present invention has extremely high toughness despite its high hardness.

Table 1 (Part 2)

Table 1 (Part 3) Rigid combination composition Combustion material composition

Alloy Ta

ヽ T iC wc TaC TaN NbC NbN Mo M0 ₂ CN i Co vc Ti w Mo V Nb Ta (Nb + Ta) Nb, N, i + C Ratio Example 1 18 40 3.2 6 0 6 0 3 2 12 9 0.8 45. S 3 4.9 0.7 5.3 5.5 10.8 1.0 0.3i 21 B

Lit 0 29.2 32 6 0 6 0 3 2 12 9 0.8 23.0 30.1 4.9 0.7 5.3 5.5 10.8 1.0 0.34 21

3 24 10 50 7 5 0 5 0 2 0 10 10 1 47.3 6.6 2 0.8 4.4 4.7 9.1 1.07 0.4 20

4 25 9 38 15 8 0 5 0 1 0 14 9 1 37 14.1 1 0.8 4.4 7.5 11.9 1.7 0.36 23

5 26 6 30 18 9 0 8 0 3 2 14 10 0 28.4 16.9 4.9 0 7.1 8.5 15.6 1.2 0.33 24

6 27 0 ・ 32 18 9 0 8 0 3 2 14 10 4 25- 1 16.S 4.9 3 -2 7.1 8.5 15.6 1.2 0.35 24

7 28 7 44 10 1.1 0 1.1 0 8 0 13 15 0.8 40.1 9.4 8 0.6 O.S 0.9 1.8 1.0 0.4 28

8 29 0 34 7 22.6 0 5.6 0 4 0 11 15 0 -8 26.7 6.6 4 0.6 5 21.2 26.2 4.24 0.3Ϊ 26

9 30 0 33.1 7 5.4 0 23.7 0 4 0 11 15 0.8 26- C 6.6 4 0.6 21 5.1 26.1 0.24 0.36 26

Z + Table 1 2 (Part 1)

Table 1 (Part 2)

Examples 22 to 63 and Comparative Examples 10 to 27 (Preparation and evaluation of cutting tools and cutting tools)

(C-1) Straight shank drill

The hard alloys obtained in the above Examples and Comparative Examples were polished into cylindrical bodies (5 j ^ mrn x 60 mm) by a diamond polisher, and as shown in Table 13, straight shank drills A and B (see Figures 1 and 2 for details). The state of the cutting edge of the obtained drill was observed, and the results are shown in Table-4. Table 1 3

(Unit: degree)

In addition, copper and SUS-304 were selected as the metals to be cut, and drilling tests were performed with a drill under the cutting conditions shown in Table 5, and the results are also shown in Table 14. Is as shown in Table 1.

Table 1 (Part 1)

Table 4 (Part 2)

Table 1 5

Table 1 6

As is clear from Table 1, the drill machined from the hard alloy of the present invention can be sharply prepared even when the cutting edge angles are 74 degrees and 65 degrees without any chipping of the cutting edges.

On the other hand, a drill machined from a Ti-based alloy having a composition other than that of the present invention suffers from chipping of the cutting edge and is not practically usable. In this case, the cutting edge is severely damaged or the metal to be cut is significantly welded. I got it.

On the other hand, in the drill using the hard alloy of the present invention, chipping of the cutting edge and welding to the metal to be cut were not observed at all even after the cutting test. This indicates that the drill made of the hard alloy of the present invention is a very excellent cutting tool.

The same applies to the end mill. The end mill made of the hard alloy of the present invention has no cutting edge and hardly adheres to the metal to be cut, indicating that it is an excellent cutting tool.

(C-1 2) Cutter

The hard alloy prepared in the above Examples and Comparative Examples was finish-processed with a diamond grindstone into a cutter having a blade angle of 16 degrees (hereinafter referred to as cutter A) and a cutter having a blade angle of 24 degrees (hereinafter referred to as cutter B). (See Figures 3 and 4 for details).

As the material to be cut, a polyvinyl chloride film containing 8% calcium carbonate and 5% titanium oxide and having a thickness of 150; "was selected. The line speed of this film was set to 5 mZrain. A power putting test was performed with the above power meter.

After the cutting test, the degree of wear on the blade edge of the cutter and the condition of the blade defect were investigated, and the results are shown in Table-7. The ₀ indicating the evaluation items and evaluation criteria in Table one 8 Table 7 (Part 1) Hard force cutter A cutter A Alloy When cutter is prepared After cutting test After force cutter is prepared After cutting test

(No.) Cutting edge condition Cutting edge condition Abrasion condition Cutting edge condition Cutting edge condition Example-43 1 ◎ ◎ ◎ ◎ ◎ ◎

44 2 ◎

45 3

46 4

47 5

48 6

49 7

50 8 \ 1 /

51 9

52 10

53 11

54 12 ψο ®οο〇 ® ◎> 〇〇 ◎.

55 13

56 14

57 15

58 16 〇 ◎ 〇〇 ◎

59 17

60 18

61 19

62 20

63 21

〇〇 ◎◎ ψ

> 〇〇 ◎◎ 〇 ◎ 〇 Table 1 7 (Part 2) Hard cutter A Cutter B alloy When preparing a power cutter After cutting test After preparing a cutter After cutting test

(No.) Cutting edge condition Cutting edge condition Wearing condition Cutting edge condition Cutting edge condition Wear ratio Ratio example 19-22 X X X X X

20 23

21 24

22 25

23 26

24 27

25 28

26 29

27 30 X X

o〇Φ〇 X x X X Ιl

〇> Table 1.

As is clear from Table 1, the cutter made of the hard alloy of the present invention was able to finish sharply at any of the cutting edge angles of 16 degrees and 24 degrees, but was processed from an alloy having a composition other than the present invention. Most of the power cutters of the comparative examples had a remarkable loss of the cutting edge and could not have a sharp cutting edge.

Of the power cutters of the comparative example, the cutters that could be sharply finished were subjected to a cutting test, and the cutting edge was damaged or worn, so that none of them could be used practically.

On the other hand, the cutter according to the present invention did not show any chipping after the cutting test, and had very little wear on the cutting edge, indicating that it was a practically useful cutting tool.

Further, it was also revealed that the force razor using the hard alloy of the present invention had no cutting edge and very little wear on the cutting edge. Industrial applicability

As described above, the hard alloy provided by the present invention has high hardness and excellent toughness, and is suitably used as a material for cutting tools, particularly cutting tools requiring hardness and Z or toughness. Can be.

Claims

The scope of the claims

1. Includes Ti, W, Mo, V, Nb, Ta, Ni, Co, C and N as essential components; Ti, W, Mo, V, Nb And at least 80 atomic% of the sum of Ta are present in the form of carbides, nitrides and / or carbonitrides; 45%, W4 ~ 28%, Mo 2 ~ 15%, V 0.2.5%, Nb 2 ~ 20%, Ta 2 ~ 20%, Ni 5.7 ~ 37.9% and Co 7.1 ~ 39.3 %; The content of the sum of Nb and Ta (Nb + Ta) is 4 to 23% and the weight: ft ratio of TaZNb is in the range of 0.9 to 3.5; The content of the sum of Ni and C0 (Ni + Co) is 20-45% and the weight ratio of NiZC0 is in the range of 0.4-1.8; and Nil child / (0 The atomic ratio of (atom + 1 ^ atom) is in the range of 0.30 to 0.60, and the atomic ratio of (total amount of C atoms and N atoms) / (total amount of the above metal atoms excluding Ni and C0) is 0.8. ~ 1.0 range Hard alloy which is characterized in that there.

2. The hard alloy according to claim 1, wherein at least 85 atomic% of the total of Ti, W, Mo, V, Nb, and Ta exists in a state of carbide, nitride, and / or carbonitride.

3. The hard alloy according to claim 1, wherein Nb exists substantially in a carbide state of Nb, and Ta exists substantially in a nitride state of Ta.

4. Based on the weight of the hard alloy, Ti 28 to 40%, W 6 to 25%, Mo 3 to 12%, V 0.2 to 2.0%, Nb 3 to 17%, Ta 3 to 1 The hard alloy according to claim 1, containing 7%, Ni 7.0 to 30%, and Co 8.0 to 35%.

5. What is the content of (N b + T a)? The hard alloy according to claim 1, wherein the content of the hard alloy is about 20%.

6. The hard alloy according to claim 1, wherein the weight ratio of D & N: ^ 13 is 1.0 to 2.5.

7. The hard alloy according to claim 1, wherein the content of (Ni + Co) is 20 to 35%.

8. The hard alloy according to claim 1, wherein the weight ratio of NiZCo is 0.6 to 1.5.

9. The hard alloy according to claim 1, wherein the weight ratio of N atoms (atomic atoms + atoms) is 0.33 to 0.50.

10. The hard material according to claim 1, wherein the atomic ratio of (total amount of C atoms and N atoms) (total amount of metal atoms excluding ZCNi and Co) is in the range of 0.82 to 0.98. alloy.

1 1. A cutting tool made of the hard alloy according to claim 1.

1 2. A cutting tool made of the hard alloy according to claim 1.

1 3. The cutting tool according to claim 12, wherein the cutting edge angle is 40 to 170 degrees.

1 4. The cutting tool according to claim 12, which is a drill or an end mill.

1 5. Each element of Ti, W, Mo, V, Nb, Ta, Ni, Co, C, and N is contained as an essential component at the ratio described in claim 1, and at that time, Each metal component of Ti, W, V, Nb and Ta exists substantially in the form of carbides, nitrides, and phosphorus or carbonitrides, and at least part of Mo is a simple metal and the remainder is carbide. Exist in the state of nitride and / or carbonitride, and 2. The method for producing a hard alloy according to claim 1, wherein a raw material powder mixture in which Ni and Co substantially exist as a simple metal is fired.

16. The method c S according to claim 15, wherein the raw material powder mixture contains Nb substantially in a carbide state, and contains Ta substantially in a nitride state.