JP3359221B2 - TiCN-based cermet tool and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a TiCN cermet tool and a method of manufacturing the same. INDUSTRIAL APPLICABILITY The cermet tool of the present invention can be suitably used for high-speed finish cutting of a high-hardness material by using its sintered surface as a cutting edge of a cutting tool.

[0002]

2. Description of the Related Art Sintered cermets containing Ti as a main component and carbides, nitrides, and carbonitrides of elements of groups 4a, 5a, and 6a as hard phase components are harder than cemented carbides that have been widely used in the past. Since the tool life is long due to its plastic deformation resistance, cutting tools have become mainstream. In particular, the TiC-based cermet has high wear resistance in finish cutting with a small depth of cut because of its high hardness due to the inherent physical properties of TiC as a main component.

In recent years, it has been proposed that TiC further contain a nitride such as TiN or a carbonitride as a hard phase. This is due to the fact that TiN itself has high toughness and high thermal conductivity.
It is intended to improve the thermal shock resistance and the thermal plastic deformation, and for example, the invention of Japanese Patent Publication No. Sho 56-5201 is known.

[0004] Thereafter, as disclosed in Japanese Patent Application Laid-Open No. 6-228702 as an attempt to improve the wear resistance and fracture resistance of such a TiN-containing cermet, a depth of about 3 to 500 µm from the surface of the sintered body is disclosed. Structures are disclosed that have the highest amount of binder phase in the range.

[0005]

However, Japanese Patent Laid-Open No. 6-2 / 1994
In the case where the sintered body described in Japanese Patent No. 28702 is used as a cutting tool, in particular, the sintered surface is used as a cutting edge of the tool.
In the case of a class tool, cutting is performed at the highest part of the amount of the binder phase, in other words, at the lowest part of the amount of the hard phase, as the wear of the tool progresses, which leads to a sharp decrease in wear resistance.

[0006] Also, a point to be noted in the manufacturing process is that Ti
Since a TiC-based cermet containing N tends to generate pores due to denitrification in the sintered body, the pressure at which nitrides and carbonitrides decompose to prevent denitrification in order to obtain a dense sintered body It is necessary to perform sintering under the above nitrogen atmosphere. Anyway,
When sintering is performed in a nitrogen atmosphere in order to suppress denitrification, an altered phase due to nitriding may occur on the surface of the sintered body.
Therefore, a production method that prevents denitrification inside the sintered body and does not generate a deteriorated phase on the surface of the sintered body has not yet been proposed.

Accordingly, a first object of the present invention is to provide a TiC having excellent fracture resistance and wear resistance regardless of the wear amount of the tool.
An object of the present invention is to provide an N cermet tool. A second object is to provide a method for producing a dense carbonitride-containing cermet sintered body having no altered phase.

[0008]

To achieve the first object, a TiCN cermet tool according to the present invention (first invention)
Is a TiCN-based cermet tool composed of a first hard phase, a second hard phase, and a binder phase metal, and has a surface portion having a depth of 5 μm from the surface on either the flank face or the rake face of the cermet tool. Is composed of the second hard phase and the binder phase metal and has a depth of 5 mm from the surface of the cermet tool.
The inside of the transition portion, in which the first hard phase increases as the second hard phase decreases toward the inside, the first hard phase and the binder phase metal inside the transition portion. And the ratio N / (C + N) of the amount of nitrogen to the total amount of carbon and nitrogen in the entire cermet is in the range of 0.2 to 0.5 in atomic ratio. The amount of the binder phase metal at the surface up to a depth of 100 μm is less than the amount of the binder phase metal inside it, and the first and second hard phases comprise Ti, non-Ti metal,
A compound having carbon and nitrogen, wherein the first hard phase has a composition structure in which Ti increases and non-Ti metal decreases toward the center thereof, and the second hard phase includes: This is a TiCN-based cermet tool having a composition structure in which Ti and non-Ti metal are uniformly dispersed.

Similarly, the TiCN-based cermet tool (second invention) of the present invention has a three-component composition diagram shown in FIG. 1 having a total composition of Ti carbide (TiC), nitride (TiN), and carbonitride.
(TiCN) and 40 to 60% by weight of one or more Ti compounds selected from solid solutions composed of two or more of these, and one or more non-Ti compounds selected from metals of Groups 4a, 5a and 6a of the Periodic Table of the Elements. 30-40% by weight of a non-Ti metal compound composed of at least one selected from the group consisting of metal carbides, nitrides, carbonitrides and solid solutions composed of two or more thereof, Co, Ni
And a composition of a region surrounded by 10 to 20% by weight of a binder phase metal of at least one iron group metal selected from the group consisting of a first hard phase, a second hard phase, and a binder phase metal. A cermet-based cermet tool having a surface portion extending from the surface of the cermet tool to a depth of 5 μm,
And a transition portion in which the second hard phase decreases toward the inside and the first hard phase increases from a depth of 5 μm from the surface of the cermet tool. And a central portion composed of the first hard phase and the binder phase metal inside the transition portion, wherein the first and second hard phases are composed of Ti, the non-Ti metal, carbon, A first hard phase having a composition structure in which Ti increases and the non-Ti metal decreases toward the center thereof, and the second hard phase includes Ti and the non-Ti metal. This is a TiCN-based cermet tool having a composition structure in which Ti metal is uniformly dispersed.

[0010] Then, even in the second invention, the ratio of nitrogen to the sum of the carbon and nitrogen (N / (C + N) ) in an atomic ratio of
The amount of the binder metal on the surface in the range of 0.2 to 0.5 and up to 100 μm deep from the surface of the cermet tool is smaller than the amount of the binder metal inside. .

[0011] Also preferred is the case where the amount of hard phase up to 100 μm from the surface of the cermet tool is greater than the amount of hard phase inside it.

More preferably, the ratio of nitrogen to the total of carbon and nitrogen (N / (C + N)) is 0.2 in atomic ratio.
~ 0.5, and the amount of the binder metal on the surface up to a depth of 100 μm from the surface of the cermet tool is less than the amount of the binder metal inside it up to a depth of 300 μm,
This is the case where the amount of the internal binder metal from the depth of 300 μm to 500 μm below the surface is smaller than the amount of the internal binder metal more than 500 μm above the surface.

More preferably, the amount of the binder phase metal increases and the amount of the hard phase relatively decreases toward the inside of the cermet tool at the transition portion.

More preferably, the depth from the surface is 100
This is the case when the amount of binder phase metal up to μm is １ ／ or less with respect to the amount of internal binder phase metal exceeding 500 μm from the surface.

More preferably, the depth from the surface is 100
the amount of binder phase metal up to μm is from 2 to 6% by weight and the amount of internal binder phase metal over 500 μm from the surface is from 7 to
20% by weight.

It has been experimentally confirmed that the cermet tool of the present invention having the above-mentioned structure exhibits excellent chipping resistance and wear resistance, particularly in finishing to medium finishing cutting with a cut depth of about 0.5 to 1.5 mm. This is considered to be because the cermet tool of the present invention has a hard phase having a double structure inside, but is homogenized near the surface.

If the content of TiC, TiN or its solid solution TiCN is less than 40% by weight, practical wear resistance as a tool cannot be obtained, and if it exceeds 60%, sinterability and chipping resistance decrease. , 40-60% by weight. 4a, 5 other than Ti
The group a and 6a element compounds fall within this range because good cutting performance was obtained at 30 to 40% by weight. If the iron group metal such as Ni or Co is less than 10% by weight, practical fracture resistance cannot be obtained as a tool, and if it exceeds 20% by weight, the wear resistance is rapidly reduced. did.

When the amount of the binder phase has a gradient composition that decreases as approaching the surface as described above, the binder phase is sufficiently present inside, so that the toughness of the tool as a whole is maintained while maintaining the toughness of the tool as a whole. , The amount of the hard phase relatively increases, so that the hardness increases. For this reason, it becomes particularly excellent in fracture resistance and abrasion resistance.

A suitable method for producing the above-mentioned TiCN-based cermet tool and a production method for attaining the second object are as follows: (1) The following Ti compounds 40 to 40 in the three-component composition diagram shown in FIG. 50% by weight, 30 to 40% by weight of the following non-Ti metal compound, and
The composition is a region surrounded by 20% by weight, and the ratio of nitrogen to the total of carbon and nitrogen (N /
(C + N)) is mixed with the raw material powder so that the atomic ratio is in the range of 0.2 to 0.5, (2) the mixed powder is pressed and formed into a compact, and (3) the compact is formed. Is heated to a liquid phase appearance temperature at a heating rate of 1 to 3 ° C./min under a reduced pressure gas atmosphere, and then (4) a liquid partial appearance temperature or higher under an inert gas atmosphere having a gas partial pressure of 100 to 500 Torr. The cermet is fired at the temperature described above to produce a cermet sintered body used for a tool.

Ti compound: One or more compounds selected from the group consisting of Ti carbides, nitrides, carbonitrides, and solid solutions composed of two or more of them. Non-Ti metal compounds: Metals of the periodic table 4a, 5a, 6a And at least one compound selected from the group consisting of carbides, nitrides, carbonitrides and two or more solid solutions of metals excluding Ti. Binder phase metals: Co, Ni, Fe and two or more thereof. At least one metal selected from the group of alloys Here, preferably, the reduced pressure gas atmosphere up to the liquid phase appearance temperature is a nitrogen atmosphere. The liquid phase appearance temperature is determined from the phase diagram of the binder phase component.

Under a reduced pressure atmosphere up to the liquid phase appearance temperature
Bubbles are discharged by raising the temperature at a gradual heating rate of about 1 to 3 ° C./min, so that generation of micropores and a pool of binder phases near the surface of the sintered body can be suppressed,
Generation of a systematic defect near the surface can be suppressed.
In addition, when compounded at an atomic ratio of N / (C + N) = 0.2 to 0.5, nitrides and carbides coexist appropriately in the sintered body, but when the temperature is increased in a nitrogen atmosphere, the hardness near the surface increases. The phase is rich in nitride. Then, since the binder phase component is hardly wet by the nitride, it moves into the inside where the nitride is relatively poor. As a result, it is considered that the gradient composition decreases as the amount of the binder phase approaches the surface as described above, and a high-hardness region with a small amount of the binder phase is generated on the surface of the sintered body.

Further, after holding at the liquid phase appearance temperature for 1 hour, baking is performed under an inert gas pressure of 100 to 500 Torr up to the maximum temperature, so that denitrification which is a problem in the nitrogen-containing cermet can be suppressed. Generation of micropores and C / N caused by denitrification that adversely affect cutting performance
Fluctuation of the ratio can be suppressed.

The present invention may have the following configuration. The overall composition is a carbide of Ti (Ti
C), nitrides (TiN), carbonitrides (TiCN), and 40 to 60% by weight of one or more Ti compounds selected from solid solutions composed of two or more thereof, and 4 of the periodic table of elements other than Ti.
a non-Ti metal compound of 30 to 40% by weight selected from the group consisting of carbides, nitrides, carbonitrides of a, 5a, and 6a group metals and solid solutions of two or more thereof;
o, having a composition of a region surrounded by 10 to 20% by weight of a binder phase metal of at least one iron group metal selected from Ni and Fe, and a ratio of nitrogen to the total of carbon and nitrogen
(N / (C + N)) is in the range of 0.2 to 0.5 in atomic ratio, and
Surface part up to 100 μm deep from the surface of the cermet tool
The amount of the binder phase metal is higher than the amount of the inner binder phase metal.
Less, a first hard phase, a second hard phase,
A cermet tool comprising a binder phase metal;
Has a double structure composed of the Ti compound and a metal compound other than the Ti, and the Ti compound is covered by the metal compound other than the Ti. A compound comprising Ti, at least one metal selected from metals of Groups 4a, 5a, and 6a of the periodic table other than Ti, carbon, and nitrogen, and having a depth of 5 μm from the surface of the cermet tool.
A TiCN-based cermet tool comprising the second hard phase and the binder phase up to m, and the first hard phase and the binder phase at a depth of 500 μm from the surface to the inside.

The following configuration may also be used. The total composition is one or more Ti compounds 40 selected from carbides (TiC), nitrides (TiN), carbonitrides (TiCN) and solid solutions of two or more of these in the ternary composition diagram.
６０60% by weight, and 4a, 5 of the periodic table of elements other than Ti
a, 30 to 40% by weight of a metal compound other than Ti selected from the group consisting of carbides, nitrides, carbonitrides of group 6a metals, and solid solutions of two or more thereof, other than Ti;
It has a composition of a region surrounded by 10 to 20% by weight of a binder phase metal of at least one iron group metal selected from Ni and Fe, and a ratio of nitrogen to the total of carbon and nitrogen (N / (C
+ N)) is in the range of 0.2 to 0.5 in atomic ratio, and
Bonding of the surface part up to 100 μm deep from the surface of the cutting tool
Phase metal is less than the amount of internal binder phase metal
A cermet tool comprising a first hard phase, a second hard phase, and a binder phase metal, wherein the first hard phase comprises the Ti compound, a metal compound other than Ti, Having a double structure in which the Ti compound is covered with a metal compound other than the Ti, and wherein the second hard phase comprises Ti
And a compound having at least one metal selected from Group 4a, 5a, and 6a metals of the periodic table other than Ti, carbon, and nitrogen, and a depth of 5 μm from the surface of the cermet tool. A transition portion composed of the second hard phase and the binder phase, and having a depth of 5 μm from the surface, in which the second hard phase decreases toward the inside and the first hard phase increases, A TiCN-based cermet tool comprising the first hard phase inside the transition portion and a central portion composed of the binder phase.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION As raw material powder, average particle size: 1.5
μm TiCN powder (TiC / TiN = 70/30), average particle size: 1.0μm T
iC powder, average particle diameter: 1.4 μm TiN powder, average particle diameter: 1.4 μm
NbC powder, average particle size: 1.6 μm WC powder, average particle size: 3.3
μm Mo ₂ C powder, average particle size: 3.0 μm Ni powder, average particle size:
A 1.5 μm Co powder was prepared, blended to have the blending composition shown in Table 1, wet-mixed in a ball mill for 72 hours, dried, and then kneaded by adding a microwax binder. Thereafter, green compacts A to I were prepared by press-molding the green compacts at a pressure of 1.5 ton / cm ² , and the binder was removed.

[0028]

[Table 1]

The green compacts A to I shown in Table 1 were charged into a baking furnace, and the inside of the baking furnace was maintained in an N ₂ atmosphere of 100 Torr or less, and a liquid phase appeared at an average temperature gradient shown in Table 2. The temperature was raised to 1200 ° C., the temperature. Thereafter, the temperature was continuously increased in an inert gas atmosphere having a pressure shown in Table 2 to a maximum temperature of 1500.
C. for 1 hour, and then cooled in an inert gas atmosphere of approximately 650 torr to obtain the ISO standard CNMG120
No. 408 (hereinafter, referred to as the present invention tool) having a shape of 408 (non-abrasive grade throwaway tip). 1-9 were produced.

Further, as a comparative example, the temperature of the same green compact was raised to 1200 ° C. in a vacuum atmosphere, and then the temperature was raised in a nitrogen atmosphere of 10 Torr and maintained at a maximum temperature of 1500 ° C. for 1 hour. By cooling in an inert gas atmosphere, a cutting tool made of comparative cermet having the shape of ISO standard CNMG120408 (hereinafter referred to as comparative tool)
No. 1-9 were produced.

[0030]

[Table 2]

After cutting the center part of the thus manufactured tool of the present invention and the comparative tool and polishing the cross-section to a mirror surface, 0 to 100 μm, 100 to 300 μm, and 300 μm to 50 μm from the flank.
Micro Vickers hardness (load load: 200 gf) in the depth range of 0 μm and 500 μm or more was measured. Further, the amount of the binding phase in each depth range was quantified by EDS. The composition of the entire cermet tool may be the same as the composition
Confirmed by EDS. Further, when the configuration of the hard phase particles was identified by SEM and EDS, in the case of the tool of the present invention, the hard phase particles up to 5 μm from the surface had a single structure mainly composed of a nitride of a 4a, 5a or 6a group element. There was a composite or double structure in which the carbonitrides of the 4a, 5a, and 6a group elements were present around TiCN, while the comparative tool had both a surface and an interior. It had a composite structure or a double structure.

Tables 3 and 4 show the measurement results of the amount of the binder phase in each depth range. The depth from the burnt surface of the tool is shown on the horizontal axis, and the amount of the binder phase within 500 μm from the surface is shown as 100.
% Is plotted on the vertical axis, and the tool N of the present invention
o. 1 and comparative tool No. FIG. 3 shows a graph plotting the measured values of No. 1.

[0032]

[Table 3]

[0024]

[Table 4] As can be seen from Tables 3 and 4, the tool of the present invention
The amount of binder phase in the depth range up to 500 μm is lower than the amount of binder phase inside it. In particular, the amount of the binder phase in the depth range from the surface to 300 μm is １ ／ or less of the amount of the inner binder phase, and the amount of the binder phase in the depth range from the surface to 100 μm is less than ３ of the amount of the inner binder phase. Had become. In contrast, the comparative tool had the same amount of binder phase both on the surface and inside.

Next, using the tool of the present invention and the comparative tool, high-speed cutting was performed under the following conditions, and the flank wear of the cutting edge was measured. Table 5 shows the results. Workpiece: SCM439 (H _B = 300) Cutting Speed: 300 (m / min) feed rate: 0.15 (mm / rev) Depth of cut: 1.5 (mm) Cutting Time: 3 (min) Cutting Conditions: Continuous dry cutting

[0024]

[Table 5]

As shown in Table 5, the flank wear of the tool of the present invention was 70 to 90% with respect to 100% of the wear of the conventional tool. This is because, as described above, the amount of the binder phase in the conventional tool is almost constant from the inside to the surface, while the amount of the binder phase in the area within 500 μm from the flank of the tool of the present invention is smaller than that in the inside. Therefore, it is considered that the hardness of the tool of the present invention increases from the inside toward the flank of the tool.

[0035]

As described above, the TiCN-based cermet tool of the present invention is excellent in chipping resistance and abrasion resistance, and thus is suitable for high-speed finish cutting of a hard material. In addition, the production method of the present invention suppresses the denitrification and does not produce a deteriorated phase,
For producing a TiC-based cermet containing
Suitable for manufacturing CN-based cermet tools.

[Brief description of the drawings]

FIG. 1 is a ternary composition diagram of a Ti compound, a metal compound other than Ti, and an iron group metal.

FIG. 2 is a schematic diagram illustrating the structure of a TiCN-based cermet tool of the present invention.

FIG. 3 is a graph plotting the relationship between the distance from the burnt surface of a TiCN-based cermet tool and the amount of a binder phase.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B23B 27/14 C22C 1/05 C22C 29/04

Claims (11)

(57) [Claims] 1. A TiCN-based cermet tool comprising a first hard phase, a second hard phase, and a binder phase metal, wherein the cermet tool has a flank face or a rake face with a depth of 5 μm from the surface. The surface portion of the cermet tool is composed of the second hard phase and the binder phase metal. From the surface of the cermet tool at a depth of 5 μm, the first hard phase decreases as the second hard phase decreases toward the inside. And a central portion comprising the first hard phase and the binder phase metal inside the transition portion, wherein the amount of nitrogen relative to the total amount of carbon and nitrogen in the entire cermet is The ratio N / (C + N) is in the range of 0.2 to 0.5 in atomic ratio, and the amount of the binder phase metal on the surface portion of the cermet tool up to a depth of 100 μm is smaller than the binder phase inside the cermet tool. Less than the amount of metal, the first The second hard phase is a compound having Ti, a non-Ti metal, carbon, and nitrogen. The first hard phase has a structure in which Ti increases toward the center and non-Ti metal decreases. The second hard phase has a composition structure in which Ti and non-Ti metal are uniformly dispersed.
iCN-based cermet tool. 2. The composition according to claim 1, wherein the total composition is at least one selected from the group consisting of carbides (TiC), nitrides (TiN), carbonitrides (TiCN), and solid solutions of at least two of these in the three-component composition diagram. 40 to 60% by weight of a Ti compound selected from metals of Groups 4a, 5a and 6a of the Periodic Table of the Elements
30 to 40% by weight of a non-Ti metal compound of at least one selected from the group consisting of carbides, nitrides, carbonitrides of at least one or more non-Ti metals and solid solutions of at least two of them; It has a composition of a region surrounded by 10 to 20% by weight of one or more binder group metals selected from iron group metals, and the ratio of nitrogen to the total of carbon and nitrogen (N / (C + N)) is
In the range of 0.2-0.5 in the ratio of the cermet tool
Amount of binder phase metal on the surface up to 100 μm deep from the surface
Is less than the amount of internal binder metal
Ri, a TiCN-base cermet tool composed of a binder phase metal and the first hard phase and the second hard phase, the surface portion to a depth of 5μm from the surface of the cermet tool, and the second hard phase A transition portion comprising the binder phase metal, wherein the second hard phase decreases toward the inside and the first hard phase increases from a depth of 5 μm from the surface of the cermet tool; A first hard phase and a central portion composed of the binder phase metal, the first and second hard phases each including Ti, the non-Ti metal, carbon, and nitrogen. The first hard phase has a composition structure in which Ti increases toward the center and the non-Ti metal decreases, and the second hard phase has a uniform structure of Ti and the non-Ti metal. A TiCN-based cermet tool having a compositional structure that disperses in a steel. 3. The amount of the hard phase up to 100 μm from the surface of the cermet tool is greater than the amount of the hard phase inside it.
3. The TiCN-based cermet tool according to any one of items 1 to 3. (4) Up to 100 μm deep from the surface of the cermet tool
The amount of binder phase metal on the surface of
Less than the amount of internal binder phase metal at a depth of 30
From 0μm to 500μm the amount of internal binder phase metal is on the surface
Less than 500 μm internal binder phase metal
3. The TiCN-based cermet according to claim 2,
Utensils. 5. A according to any one of claims 1 to 4, the amount of the hard phase increases the amount of binding phase metal towards the interior of the cermet tool in the transition section is relatively lowered Ti
CN-based cermet tool. 6. A binding phase metal to a depth of 100μm from the surface amount according to any one of claims 1 to 5, 1/2 or less relative to the amount of binding phase metal of the internal exceeding 500μm from the surface TiCN based cermet tool. 7. The amount of binder phase metal from the surface to a depth of 100 μm is 2 to 6% by weight, and the amount of internal binder phase metal exceeding 500 μm from the surface is 7 to 20% by weight. A TiCN-based cermet tool according to any one of claims 1 to 6 . 8. (1) In the three-component composition diagram, the following Ti compound 40 to 50% by weight, the following non-Ti metal compound 30
４０40% by weight and the following binder phase metal in a region surrounded by 10 組成 20% by weight, and the ratio of nitrogen to the total of carbon and nitrogen in the composition (N / (C + N))
The raw material powder is mixed such that the atomic ratio is in the range of 0.2 to 0.5. (2) The mixed powder is molded under pressure to form a compact. After raising the temperature to a liquid phase appearance temperature at a temperature rising rate of 1 to 3 ° C./min, (4) In an atmosphere of an inert gas having a gas partial pressure of 100 to 500 Torr, at a temperature higher than the liquid phase appearance temperature. A method for producing a TiCN-based cermet tool, comprising sintering to obtain a cermet sintered body used for a tool. Ti compound: at least one compound selected from the group consisting of Ti carbides, nitrides, carbonitrides, and solid solutions composed of two or more of them. Non-Ti metal compounds: Among metals in the periodic table 4a, 5a, and 6a of the elemental periodic table. At least one compound selected from the group consisting of carbides, nitrides, carbonitrides and two or more solid solutions of metals excluding Ti Binder phase metals: Co, Ni, Fe and alloys composed of two or more of these One or more metals selected from the group 9. The TiC according to claim 8 , wherein the reduced pressure gas atmosphere up to the liquid phase appearance temperature is a nitrogen atmosphere.
A method for manufacturing an N-based cermet tool. 10. The total composition is at least one selected from carbides (TiC), nitrides (TiN), carbonitrides (TiCN), and solid solutions of at least two of these in a three-component composition diagram. And at least one selected from the group consisting of carbides, nitrides, carbonitrides, and solid solutions of two or more of metals belonging to groups 4a, 5a, and 6a of the periodic table other than Ti. has a non-Ti metal compounds 30-40 wt%, Co, the composition of the region surrounded by the 10 to 20% by weight of iron group metal one or more binding phase metal selected from among Ni and Fe consisting of carbon The ratio of nitrogen to the total of nitrogen and nitrogen (N / (C + N))
In the range of 0.2-0.5 in the ratio of the cermet tool
Amount of binder phase metal on the surface up to 100 μm deep from the surface
Is less than the amount of internal binder metal
A cermet tool comprising a first hard phase, a second hard phase and a binder phase metal, wherein the first hard phase comprises the Ti compound and a metal compound other than Ti The Ti compound has a double structure in which the Ti compound is covered with a metal compound other than Ti, and the second hard phase is composed of Ti and a metal belonging to Group 4a, 5a, or 6a of the periodic table other than Ti. A compound having at least one selected metal, carbon, and nitrogen, wherein the depth of the second surface from the surface of the cermet tool is 5 μm;
A TiCN-based cermet tool comprising the first hard phase and the binder phase at a depth of 500 μm from the surface. 11. The total composition is at least one selected from the group consisting of a carbide of Ti (TiC), a nitride (TiN), a carbonitride (TiCN) and a solid solution comprising at least two of these in a three-component composition diagram. And at least one selected from the group consisting of carbides, nitrides, carbonitrides, and solid solutions of two or more of metals belonging to groups 4a, 5a, and 6a of the periodic table other than Ti. A composition of a region surrounded by 30 to 40% by weight of a metal compound other than Ti consisting of: and 10 to 20% by weight of a binder phase metal of at least one iron group metal selected from Co, Ni and Fe; The ratio of nitrogen to the sum of carbon and nitrogen (N / (C + N))
In the range of 0.2-0.5 in the ratio of the cermet tool
Amount of binder phase metal on the surface up to 100 μm deep from the surface
Is less than the amount of internal binder metal
A cermet tool comprising a first hard phase, a second hard phase and a binder phase metal, wherein the first hard phase comprises the Ti compound and a metal compound other than Ti The Ti compound has a double structure in which the Ti compound is covered with a metal compound other than Ti, and the second hard phase is composed of Ti and a metal belonging to Group 4a, 5a, or 6a of the periodic table other than Ti. A compound having at least one selected metal, carbon, and nitrogen, wherein the depth of the second surface from the surface of the cermet tool is 5 μm;
A transition portion where the second hard phase decreases toward the inside and the first hard phase increases, and the transition portion includes a hard phase having a depth of 5 μm from the surface. A TiCN-based cermet tool comprising a more internal first hard phase and a central portion comprising the binder phase.