JP2002205203A - Multilayer covering tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a covering tool having a titanium zirconium carbonitroxide film to be further excellent in oxidation resistance and resistance to cracking of a film than those of a conventional covering tool and extremely excellent in a tool life. SOLUTION: A multilayer covering tool is featured that a layer having a diploid structure consisting of a titanium zirconium carbonitroxide layer and a zirconium carbonitride layer forms a unit layer and/or a layer having a diploid structure consisting of a titanium zirconium carbonitroxide layer and a zirconium carbonitroxide layer forms a unit layer and a tool substrate is covered by at least one unit layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coated tool used as a cutting tool, a wear-resistant tool or the like.
Group A metal and aluminum carbide, nitride, carbonitride, carbonate, nitride, and carbonitride have a multilayer film composed of any two or more layers. The present invention relates to a multi-layer coated tool having at least one zirconium carbonitride oxide film and at least one zirconium carbonitride film.

[0002]

2. Description of the Related Art A coated tool in which a single-layer or multi-layer hard coating is applied to the surface of a tool base made of cemented carbide, high-speed steel, special steel, or the like has a high wear resistance and a high toughness of the base. It is widely used for practical use. In particular, when cutting at high speed or when turning without using a cutting fluid, the cutting edge temperature of the cutting tool reaches around 1000 ° C, so wear and intermittent cutting due to contact with the work material in a high temperature environment It is necessary to withstand mechanical shocks such as those described above, and coated tools excellent in both wear resistance and toughness are commonly used.

[0003] Generally, a hard film of a coated tool is required to have excellent wear resistance and toughness, and is therefore made of a carbide, nitride or carbonitride of a metal belonging to Group 4a, 5a or 6a of the periodic table. A film is used, and an aluminum oxide film having excellent oxidation resistance is also used. As is well known, these hard films are formed by CVD or P
The film is formed by the VD method. The PVD method has a feature that a film containing a large number of elements can be formed relatively easily, but the adhesion between the substrate and the film and between the films is smaller than that of the film formed by the CVD method. There is a disadvantage that it is inferior.
On the other hand, the CVD method has a drawback that it is difficult to form a film containing a large number of elements because the film is formed by using a chemical reaction, but the film is formed at a high temperature of 600 to 1050 ° C. Therefore, the film has characteristics such as high adhesion of the film and little deterioration of film characteristics even when used at a high temperature.

[0004] For this reason, TiC, TiN, TiCN, Al ₂ O ₃ films and the like formed by a CVD method have been put into practical use as films for turning tools and the like whose cutting edges rise to relatively high temperatures during cutting. It's just that. Among these commercially available films, the TiC, TiN, and TiCN films have Vickers hardnesses Hv of about 3200, 210 measured at room temperature.
Since it is very hard at 0 and 2700 and has excellent wear resistance, it is frequently used as a film of a turning tool. But,
These films, such as a TiCN film, have a blade edge temperature of 1
When the temperature reaches a high temperature range exceeding 000 ° C., there is a drawback that the tool life is inferior, for example, the hardness is reduced and the film is easily oxidized, and cracks are formed in the film and crystal grains are dropped.

[0005] As an improvement in the properties of these films,
For example, a surface defining the highest peak intensity in the X-ray diffraction of the TiCN layer (JP-A-6-158324,
JP-A-6-158325 and JP-A-7-62542
No.) and those defining the chlorine content in the film (Japanese Patent Application Laid-Open No.
-100701) and the like, and the applicant of the present application has also proposed one in which the film thickness, the structure and the like are specified (Japanese Patent No. 266).
0180).

In order to improve the characteristics of these TiC, TiN, and TiCN films, (Ti, Al) N, (Ti,
Films containing two or more types of metal components such as Zr) N and (Ti, Zr) C have been studied. However, known films containing these two or more metal components are all formed by a PVD method such as a sputtering method or an ion plating method, or a plasma CVD method, and the film formation temperature is low. In addition, there is a problem in the adhesion of the film. Further, the hardness of the film is low, and there is a problem in abrasion resistance.

On the other hand, by forming a film by a thermal CVD method,
To improve the adhesion by obtaining a Zr-containing film having a residual tensile stress is disclosed in JP-A-1-252305 and JP-A-5-205305.
No. 177412 and Japanese Patent Application Laid-Open No. 5-177413 disclose and are proposed. However, the films in the inventions disclosed in these publications include a ZrC film, a ZrN film, and a ZrC film.
An N film, a ZrCO film, and a ZrCNO film, all of which are CVD films in which the metal component consists only of Zr. The hardness of a film such as a ZrC film in which the metal element is made of Zr alone is low at room temperature. Therefore, when the cutting edge temperature is used at a relatively low temperature, such as wet cutting or low-speed cutting, there is a disadvantage that the wear resistance is poor.

Further, a plurality of metal components, for example, Ti and Zr
As a film containing both, a film was formed by a plasma CVD method according to JP-A-3-267361 (Ti,
A Zr) N film is disclosed. However, the known film forming method using the plasma CVD method has a problem due to a low film forming temperature as described above, and chlorine remains in the film, and the hardness of the film becomes low, so that a tool is formed. However, there is a defect that the abrasion resistance is poor. Further, in the invention described in this publication, an alumina plate is used for the substrate, and since the substrate itself has low toughness, the substrate tends to be chipped when used as a tool, and there is a problem in cutting durability characteristics.

[0009]

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies to solve the above-mentioned drawbacks of the coated tool in the prior art, and as a result, have found that a hard film containing titanium and zirconium as metal components, for example, (Ti, It has been found that, when specific conditions are satisfied in a Zr) CN film or the like, the film hardness does not decrease sharply even at a high temperature, and a film having excellent film adhesion and wear resistance can be realized. 11-1
No. 82622 and Japanese Patent Application No. 11-355004 have disclosed the technology.

[0010] In order to improve the wear resistance of a titanium carbonitride film, a titanium carbonitride film, etc., which has been conventionally used in coated tools, a method of coating a film of titanium zirconium carbonitride on a tool substrate is known. Recently proposed (Tokuheihei 11
510856). In this method, a carbonitride film containing at least two kinds of metal elements is formed by using a CN compound gas to form a carbon nitride film.
This is a method of coating by the VD method. However, as a result of the inventors' re-examination according to the technology described in the publication, the obtained titanium-zirconium carbonitride film has a large crystal grain size, and does not necessarily satisfy the wear resistance and chipping resistance as a tool. Did not.

The present invention is a further development of the invention previously proposed by the inventors of the present invention, that is, the invention relating to a hard film containing titanium and zirconium as metal components, and has abrasion resistance, chipping resistance, and high-temperature hardness. It is an object of the present invention to provide a coated tool having excellent tool life and a long tool life.
That is, the problem to be solved by the present invention based on these actual conditions is to have a titanium zirconium oxycarbonitride film in which the oxidation resistance and crack resistance of the film are superior to those of the prior art and the tool life is remarkably excellent. An object of the present invention is to provide a coated tool.

[0012]

All of the conventional inventions described above focus on only the carbonitride layer of titanium or the carbonitride layer of titanium-zirconium, and many of them have improved contents. . The inventors of the present application studied the improvement of the properties of the individual films and also examined the relativity of the films. As a result, the titanium zirconium carbonitride oxide film having excellent high-temperature abrasion resistance and a small crystal grain size was obtained. By combining a zirconium carbonitride film or a zirconium carbonitride oxide film having excellent oxidation resistance, it has been found that both characteristics can be combined and the crack resistance can be further enhanced, and the present invention has been completed.

That is, the present invention provides a method for forming a layer of a metal of Group 4a, 5a, or 6a of the periodic table and a carbide, nitride, carbonitride, carbonate, oxynitride, or carbonitride of aluminum on the surface of a tool base. Among them, a multilayer film composed of any two or more kinds of layers, and in the multilayer film, a layer having a multilayer structure composed of a titanium zirconium carbonitride oxide layer and a zirconium carbonitride layer is formed as a unit layer or / and / or a carbon layer. A multilayer coated tool comprising: a unit layer having a multilayer structure composed of a titanium zirconium oxynitride layer and a zirconium carbonitride oxide layer; and at least one unit layer on the tool base. is there.

The multilayer coated tool of the present invention is a unit layer having a multilayer structure composed of a titanium zirconium carbonitride layer and a zirconium carbonitride layer, or a unit layer having a multilayer structure composed of a titanium zirconium carbonitride layer and a zirconium carbonitride layer. In addition to containing each layer alone, these two unit layers may be mixed and contained.

According to the present invention, cemented carbide, cermet,
Using a well-known tool base made of high-speed steel, special steel, etc., and having a multilayer film including at least one unit layer, preferably a composite structure layer of two or more unit layers, has an excellent tool life. A multilayer coated tool is obtained. Although the reason is not clear, the high-temperature wear resistance is excellent, the titanium zirconium carbonitride film having a small crystal grain size, and the zirconium carbonitride or zirconium carbonitride layer having excellent crack resistance and oxidation resistance. The combination of high-temperature abrasion resistance, thermal conductivity and oxidation resistance are all well-balanced,
Furthermore, the cracks generated in the outer film of the unit layer are blocked at the boundary region between the two films and are hardly propagated in the film thickness direction, so that the crack resistance is further improved, and the coating having excellent tool life is provided. It is believed that a layer is obtained.

In the present invention, at least one unit layer having a multilayer structure composed of the titanium zirconium carbonitride layer and the zirconium carbonitride or zirconium carbonitride layer must be present in the multilayer film. Is preferably a multilayer coating film containing two or more unit layers.
This makes it difficult for cracks to run in the film thickness direction between the titanium zirconium carbonitride layer and the zirconium carbonitride layer or the zirconium carbonitride layer, so that crack resistance is further improved, and a more favorable tool is provided. It is considered that a coating layer having a long life can be obtained.

In the present invention, the zirconium carbonitride layer or the zirconium carbonitride in at least one unit layer is preferably formed on the titanium zirconium carbonitride. Even if tool wear progresses,
The presence of the zirconium carbonitride layer or the zirconium carbonitride oxide layer, which is rich in oxidation resistance, prevents the oxidation of the inner layer and has good crack resistance. is there.

In the present invention, the titanium zirconium oxycarbonitride layer and the zirconium carbonitride or zirconium carbonitride layer in the unit layer have a thickness ratio (titanium oxynitride / zirconium carbonitride layer / zirconium carbonitride layer or carbonitride oxide). (Titanium zirconium layer / zirconium carbonitride layer) should be in the range of 0.5 to 100, preferably 1 to 100.
The range is 50. When the thickness ratio is less than 0.5 or more than 100, the effect of forming a layer having a multilayer structure is small, and crack resistance is reduced. In a preferred range, the balance among crack resistance, oxidation resistance, and film hardness is particularly improved, and excellent tool characteristics can be obtained.

In the present invention, titanium carbide, zirconium carbonitride layer or zirconium carbonitride layer, which constitutes a unit layer having a multilayer structure, is provided between titanium carbide,
Titanium nitride, titanium carbonitride, titanium aluminum nitride,
It is also effective to insert a thin layer of zirconium carbide, zirconium nitride or the like to further enhance the adhesion between the two layers.

In the present invention, the zirconium content in at least one set of unit layers constituting the multilayer structure or the titanium zirconium oxycarbonitride film constituting one set of unit layers is 0.3%. Preferably, it is contained in an amount of from 50 to 50% by mass. 0.3 to 50% by mass of zirconium in the film
By containing Zirconium, the effect of Zirconium inclusion, that is, good heat resistance and high-temperature high strength can be obtained. If it is less than 0.3% by mass, the effect of containing zirconium is small, and if it exceeds 50% by mass, the film hardness at room temperature is lower than that of the TiC film or TiCN film, and as a result, the cutting durability tends to decrease. In addition, zirconium is 1 to 40
When it is contained by mass%, more favorable heat resistance and high-temperature high strength can be obtained, so the more preferable zirconium content is 1 to 40 mass%. Furthermore, when 5 to 30% by mass of zirconium is contained, the best heat resistance and high temperature and high strength characteristics of the zirconium-containing film appear, and the best cutting durability is obtained. Most preferably, the amount is in the range of 5 to 30% by weight. The content of zirconium can be adjusted by appropriately adjusting the concentration of a zirconium supply gas (for example, ZrCl4 or the like) in the source gas and optimizing the amount of zirconium in the film in a manufacturing method described later.

In the present invention, the oxygen content in the titanium zirconium oxycarbonitride film constituting at least one set of the unit layers constituting the multilayer structure or the unit layer constituting the set of unit layers may be 0.1 to 0.1%. More preferably, the content is from 0.05 to 10% by mass. When the film contains 0.05 to 10% by mass of oxygen, the intensity of the X-ray diffraction peak of the titanium zirconium carbonitride film having a surface index of (422) or (311) increases, And the average crystal grain size on the film surface is reduced, and more excellent cutting durability is obtained. If the oxygen content is less than 0.05% by mass, the effect of oxygen content is relatively small. On the other hand, if it exceeds 10% by mass, the film hardness at room temperature decreases, and as a result, the cutting durability tends to decrease. When oxygen is contained in an amount of 0.3 to 5% by mass, the above-mentioned characteristics of the titanium zirconium carbonitride film appear more strongly. When oxygen is contained in an amount of 0.3 to 3% by mass, the above characteristics of the titanium zirconium carbonitride film are most remarkably exhibited, and the best cutting durability is obtained. Therefore,
A more preferred oxygen content is 0.3-5% by weight, and the most preferred oxygen content is in the range of 0.3-3% by weight.

The zirconium content and oxygen content of the titanium zirconium carbonitride layer alone or the unit layer composed of the titanium zirconium carbonitride oxide layer and the zirconium carbonitride layer or the zirconium carbonitride oxide layer are polished. By using an energy dispersive X-ray analyzer (EDX). Since the measurement area of the EDX measuring device attached to the scanning electron microscope (SEM) used for general measurement is as large as about 2 μm or less, when the thickness of the titanium zirconium carbonitride layer is about 2 μm or more, titanium zirconium carbonitride is used. The zirconium content and oxygen content of the film alone can be measured, but when the thickness of the titanium zirconium carbonitride film is less than about 2 μm, it is not possible to measure the zirconium content or oxygen content of the film alone. difficult. At this time, the average zirconium amount and the average oxygen amount of the entire multilayer film region can be measured by expanding the measurement range of EDX to the width of the multilayer film region to be measured × the length of 10 μm. The zirconium content and the oxygen content of the titanium zirconium carbonitride layer alone can be calculated by proportionally dividing the film thickness ratio of the layers.
Also in this case, the zirconium content and the oxygen content of each film alone can be analyzed by using a transmission electron microscope (TEM).

The carbon oxide gas used for forming the titanium zirconium oxynitride film or the zirconium oxycarbonitride film is as follows:
Known gases such as C ₃ O ₂ and C ₅ O ₂ can be used, but it is preferable to use CO gas, CO 2 gas, or a mixed gas thereof. By using these gases, there is an advantage that oxygen can be supplied stably at lower cost and industrially than when other carbon oxide gases such as C ₃ O ₂ and C ₅ O ₂ are used. Further, the amount of oxygen in the film can be adjusted by optimizing the concentration of an oxygen supply gas such as CO or CO ₂ in a source gas in a manufacturing method or the like to be described later. There is an advantage that optimal conditions can be set for obtaining an excellent tool life with a columnar structure.

In the present invention, at least one of the titanium zirconium carbonitride films in the multilayer structural unit layer has a maximum equivalent X-ray diffraction intensity ratio PR from the (422) plane or the (311) plane. Preferably, there is. As a result, the titanium zirconium oxycarbonitride layer has high crystallinity, as well as more excellent wear resistance and toughness, and a good tool life can be obtained. This film can be formed by optimizing the conditions for forming the titanium zirconium carbonitride film. For example, when the film formation temperature of the titanium zirconium carbonitride is in the temperature range of 700 to 950 ° C,
Equivalent X-ray diffraction intensity ratio P of (422) plane and (311) plane
R increases. At high temperatures exceeding 950 ° C (2
There is a tendency that the equivalent X-ray diffraction intensity ratio PR of the (20) plane and the (111) plane becomes large.

In the present invention, it is preferable that at least one titanium zirconium carbonitride film constituting the multilayer structural unit layer has an elongated columnar structure in its thickness direction. Since the titanium zirconium carbonitride layer is elongated and continuous in the film thickness direction, coarsening of crystal grains can be prevented and a good tool life can be obtained. To form the titanium zirconium carbonitride layer, for example, at 700 to 950 ° C., and preferably, an organic CN compound gas as a source gas,
It can be manufactured by forming a film by a thermal CVD method using a halogenated gas of titanium and a halogenated gas of zirconium.

In the present invention, it is preferable that at least one unit layer in the multilayer structural unit layer is formed immediately above a titanium carbonitride layer or a titanium carbonitride layer. . Thereby, the titanium zirconium oxycarbonitride layer in the multilayer structural unit layer easily has the maximum equivalent X-ray diffraction intensity ratio PR from the (422) plane or the (311) plane, and is elongated in the film thickness direction. It becomes easier to have a columnar structure. As a result, the titanium zirconium oxycarbonitride layer has high crystallinity, crystal grains can be prevented from becoming coarse, wear resistance and toughness are further improved, and a better tool life can be obtained.

The X-ray diffraction of titanium zirconium oxynitride is based on a JCPDS file (Powder Diffraction File Publis) of a substance close to the film composition of titanium zirconium oxynitride.
hed by JCPDS International Center for Diffraction
Data) in the same manner. That is, in the examples described later, since the X-ray diffraction of titanium zirconium carbonitride is not described in the JCPDS file, the X-ray diffraction data of TiC and TiN (JCPDS files No. 29-1361 and No. 3) are not described.
8-1420) and an X-ray diffraction pattern obtained by actually measuring the product of the present invention.

[0028]

[Table 1]

Here, the X-ray diffraction pattern is CuK
with alpha ₁ line (lambda = 0.15405 nm), as measured surface of the tool surface film portion of the flat portion of the sample is measured in the range of 2θ = 10~145 ° by 2 [Theta]-theta scan technique. The background was removed by software built in the apparatus. The lattice constant of titanium zirconium oxynitride is 0.42
Since TiC and T appear in the X-ray diffraction peak measured on the basis of the 2θ value in Table 1,
iN, WC (JCPDS file No. 25-104
The X-ray diffraction peak of titanium zirconium carbonitride was determined in consideration of the positional relationship with the peaks such as 7).

[0030]

[Table 2]

From Table 2, the equivalent X-ray diffraction intensity ratio PR (hl
k) was defined by the following formula in order to quantitatively evaluate the X-ray diffraction peak intensity from the (hlk) plane of titanium zirconium carbonitride. This value indicates the relative intensity of the actually measured X-ray diffraction peak intensity I (hkl) of the coating with respect to the X-ray diffraction peak intensity I0 (hkl) of the isotropic particles described in Table 1. As the PR (hkl) value increases, the X from the (hkl) plane increases.
The X-ray diffraction peak intensity is stronger than the other X-ray diffraction peak intensities, indicating that the (hkl) plane of the film is strongly oriented in a direction parallel to the substrate.

[0032]

(Equation 1)

Where Σ is (111), (200),
(220), (311), (222), (422),
(420) and (511) indicate that the sum is obtained by eight (hkl).

In the coated tool of the present invention, the titanium zirconium oxycarbonitride layer, the zirconium carbonitride layer or the zirconium oxycarbonitride layer comprises (Ti, Zr) (C, N, O)
It is not limited to Zr (C, N) or Zr (C, N, O). These components include, for example, Cr, Ta, Nb, Zr, H
A layer in which f, Mg, Y, Si, and B are used alone or in combination of two or more and each element is added by 0.3 to 10% by mass may be used. 0.3
When the amount is less than 10% by mass, the effect of adding these components is not exhibited. When the amount exceeds 10% by mass, the characteristics of the titanium zirconium carbonitride layer and the zirconium carbonitride layer are lowered. Also,
The layer is allowed to contain impurities such as W and Co, for example, up to about several mass% within a range not to lose the effect of the present invention.

In the coated tool of the present invention, the base film of the unit layer having the multilayer structure is not limited to a titanium carbonitride layer or a titanium carbonitride, but may be, for example, a titanium carbide film or a base film. A titanium nitride film, a zirconium carbide film, a zirconium nitride film, or a zirconium carbonitride film can be used. Furthermore, in the coated tool of the present invention, the unit layer having the multilayer structure does not necessarily need to be the outermost layer film.
For example, an α-type aluminum oxide film, a κ-type aluminum oxide film, a zirconium oxide film, or a composite film thereof, and a titanium compound (for example, a titanium nitride film or a titanium carbonitride film and a multilayer film thereof), A zirconium compound (for example, zirconium nitride, zirconium carbide, zirconium carbonitride, and a multilayer film thereof) may be coated.

In the multilayer coated tool of the present invention, the unit layer having the multilayer structure is formed by a thermal CVD method, and the residual stress of the film is preferably a tensile stress. Or a PVD method such as an arc ion plating method. However, plasma CV
When the film is formed by the method D, the amount of chlorine in the film exceeds 2% by mass, the film hardness and the wear resistance are reduced, and the disadvantage that the tool life is shortened tends to appear. In addition, when the film is formed by the PVD method, the residual stress of the film becomes a compressive stress, the adhesion of the film to the base is reduced, the film is easily peeled, and the disadvantage that the tool life is shortened is likely to appear.

[0037]

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the multilayer coated tool of the present invention will be described.
The present invention will be described specifically with reference to examples and the like, but the present invention is not limited to these examples.

(Example 1) WC: 72% by mass, TiC:
On a cemented carbide indexable chip having a composition of 8% by mass, (Ta, Nb) C: 11% by mass and Co: 9% by mass, a thickness of 0.4 μm at a film forming temperature of 900 ° C. by a thermal CVD method.
m titanium nitride film was formed first. Subsequently, the film formation temperature 8
50 ° C., the raw material gas was TiCl ₄ gas: 1.5 vol%,
CH ₃ CN gas: 1.0 vol%, N ₂ gas: 45 vol
A raw material gas composed of 1% and the remaining H ₂ carrier gas was flowed into the CVD furnace at a rate of 6000 ml / min.
A 1 μm thick titanium carbonitride film was formed at 5.0 kPa. Next, 1.5 vol% of TiCl ₄ gas, ZrCl ₄
1.5 vol% of gas, 1.0 vol% of CH ₃ CN gas,
0.5 to 2.5 vo mixed gas of CO gas and CO ₂ gas
1%, 45 vol% of N ₂ gas and residual H ₂ carrier gas are flowed into the CVD furnace at a rate of 6000 ml / min, a film forming pressure of 5.0 kPa, and a film forming temperature of 750 to 95.
By reacting under the condition changed in the range of 0 ° C., T
A titanium zirconium carbonitride film made of i and Zr, C, N, O was formed. Subsequently, a film forming temperature of 700 to 950
° C, the raw material gas was ZrCl ₄ gas: 1.5 vol%, CH
₃ CN gas: 1.0vol%, _{N 2} gas: 45 vol
%, And a source gas composed of the remaining H ₂ carrier gas is flowed into the CVD furnace at a rate of 6000 ml / min.
A zirconium carbonitride layer was formed at 0 kPa. The multi-layered structure having the titanium zirconium oxynitride layer and the zirconium carbonitride layer as one set is a unit layer, and 1 to 26 sets of multi-layered structure unit layers are laminated to form a carbon oxynitride having a total thickness of 9 μm. A multilayer film composed of a titanium zirconium layer and a zirconium carbonitride layer was formed. In addition, so that the total film thickness is 9 μm,
As the number of film formation sets increases from one to 25,
The film formation time of both the titanium zirconium carbonitride layer and the zirconium carbonitride layer was reduced uniformly. Table 3 shows the samples.
Shown in

[0039]

[Table 3]

The following samples were prepared for comparison. As Comparative Example 27, an example of a single layer of titanium zirconium carbonitride and 9 μm in thickness was used. As Comparative Example 28, a titanium nitride film of 0.4 μm in thickness, a titanium carbonitride film of 1 μm in thickness, and a thickness of 7 .6 μm zirconium carbonitride is deposited,
An example having a total film thickness of 9 μm was manufactured.

FIG. 1 shows a scanning section of a film section of a multilayer structure having a main layer of a unit layer composed of a titanium zirconium carbonitride oxide layer and a zirconium carbonitride layer of Sample No. 1 shown in Table 3. It was taken with an electron microscope. FIG.
The titanium zirconium oxynitride layer and the zirconium carbonitride layer constituting the unit layer film of the sample No. 1 which is the product of the present invention have a columnar structure elongated in the film thickness direction, and the titanium zirconium oxynitride layer and the zirconium carbonitride It can be seen that the crystal grain boundary with the layer is continuous in a direction substantially perpendicular to the film thickness. FIG. 2 shows that the oxygen content of the prepared titanium zirconium carbonitride layer or the unit layer composed of the titanium zirconium carbonitride oxide layer and the zirconium carbonitride layer was determined by measuring the polished cross section of the film by an energy dispersive X-ray analyzer (EDX). It measured using.
When the thickness of the titanium zirconium oxycarbonitride layer was about 2 μm or more (sample numbers 17 to 26), the amount of oxygen in the titanium zirconium oxycarbonitride layer alone was measured. The thickness of the titanium carbonitride zirconium layer is less than about 2 μm (sample numbers 1 to 1).
In the case of 6), the thickness × length of the multilayer film for measuring the measurement range of EDX was expanded to 10 μm, and the average oxygen amount of the entire multilayer film was measured.

FIG. 2 shows the measurement results of the X-ray diffraction pattern of the coating on the flat part of the tool surface of sample No. 7. Table 3 summarizes the 2θ value of each peak, the X-ray diffraction intensity, and the lattice constant obtained from each 2θ value of the titanium zirconium carbonitride film obtained from the X-ray diffraction pattern of FIG. 2 according to the present invention.
FIG. 3 shows an equivalent X-ray diffraction intensity ratio PR of each (hkl) surface of the titanium zirconium carbonitride oxide film of Sample No. 7 obtained from FIG.
(Hkl) are shown together. It can be seen that the equivalent X-ray diffraction intensity ratio PR of this sample is the largest at the (422) plane, followed by (311).

Using the multilayer coated tool of the present invention obtained as described above, continuous cutting was performed under the following conditions, and the tool life of the coated tool was evaluated. Work material: SCM435 (HS40) Cutting speed: 240 m / min Feed: 0.40 mm / rev Depth of cut: 2.5 mm Dry cutting Here, the cutting condition is checked at 2-minute intervals, and the average flank wear is 0.35 mm. The time when the crater wear reached one of 0.1 mm and the boundary wear reached 0.5 mm was determined as the continuous cutting life, and this was defined as the tool life. The results are also shown in Table 3.

From Table 3, it can be seen that the multilayer coated tool according to the present invention is:
In each case, the continuous cutting life is as long as 10 minutes or more, which is excellent. In Table 3, sample numbers 19, 25, and 2
Sample No. 2 of titanium zirconium carbonitride oxide layer 6 alone
The average oxygen content in the unit layer in 3, 14, 16 is about 1-2%
In the present invention example, even when the zirconium content and the oxygen content in the film are almost the same, the tool life of two sets of unit layers having a multilayer structure is longer and better than that of one set. It can be seen that three or more sets are more excellent. That is, when the sample number 26 and the sample number 25 are compared, the number of units increases from one set to two sets, so that the continuous cutting life becomes 1
1.6 times longer from 0 minutes to 16 minutes, and 3 unit layers
In the case of the set (sample No. 19), the continuous cutting life was 22 minutes, which is 1.4 times longer, indicating that the continuous cutting life was even better. As the number of unit layers increased to 5 sets (sample No. 16), 8 sets (sample No. 15), and 15 sets (sample No. 7), the continuous cutting life was 24 minutes, 26 minutes, and 28 minutes. It is getting longer. When the number of sets is 10 or more, the continuous cutting life tends to be saturated. However, the total thickness is limited to 9 μm, and the thickness of the unit layer becomes thinner as the number of sets increases. It is thought to become. It can be seen that there is an optimum range of the number of units for the entire film thickness.

Further, in the sample composed of three sets of unit layers of sample Nos. 17 to 24, when the oxygen content in the titanium zirconium carbonitride film is 11.5% by mass, the continuous cutting life is 14 minutes. On the other hand, when the content is 0.05 to 10% by mass, the continuous cutting life is as long as 18 minutes or more, and when the oxygen content in the titanium zirconium carbonitride is 0.3 to 5% by mass, When the continuous cutting life is longer than 20 minutes and the oxygen content is 0.3 to 3% by mass, the continuous cutting life is 2 minutes.
The longest time is 2 minutes or more, which indicates that the cutting durability is the best. Further, in Sample Nos. 5 to 13, the content of oxygen in the multilayer film was 8.4% by mass (since the thickness ratio between titanium zirconium carbonitride and zirconium carbonitride was about 4: 1, (Corresponding to about 10.5% by mass when converted to a zirconium layer alone), the continuous cutting life is 22 minutes, while the oxygen content in the multilayer film is 0.05 to 7.9% by mass. % (Corresponding to 0.05 to 9.9% by mass), the continuous cutting life becomes longer than 24 minutes, and the oxygen content becomes 0.3 to 3.9% by mass (0.3 to 9.9% by mass).
In the case of 5.0 mass%, the continuous cutting life is further extended to 26 minutes or more, and the oxygen content is 0.3 to 2.3 mass% (same as above, about 0.3 to 3.0 mass%). ), The continuous cutting life is the longest at 28 minutes or more, and it can be seen that the cutting durability characteristics are the most excellent. That is, in the coated tool of the present invention, it is essential to contain oxygen in the titanium zirconium carbonitride layer, but the content is preferably 10% by mass or less, more preferably 0.3 to 5% by mass. %. Further, in order to obtain the most excellent characteristics, the oxygen in the titanium zirconium carbonitride oxide layer is reduced to 0.1.
Most preferably, it is in the range of 3 to 3% by mass.

In the case of the single layer of Comparative Example 27, the single layer was peeled off without adhering to the substrate, and the life was initially shortened.
8 is due to oxidation of the film or cracks in the film,
Wear progressed rapidly and the continuous cutting life was 6 minutes. In addition, the tool life of the invention example, one unit layer coating of Sample No. 26, is about 1.7 times better than Comparative Example 28, which coats a single layer of titanium zirconium carbonitride.

Example 2 In order to clarify the influence of the Zr content in the titanium zirconium carbonitride layer in the product of the present invention, the same thickness as in Example 1 was applied to the surface of the cemented carbide substrate for a cutting tool. After forming a 0.4 μm titanium nitride film, a 1 μm thick titanium carbonitride film was formed. Then, immediately above, 0.3 to 2.5 vol% of TiCl ₄ gas, Z
RCL ₄ gas 0.3~2.5vol%, _CH 3 CN gas 0.6~5vol%, 1.0vol%, a mixed gas of CO gas and CO ₂ gas, _{N 2} gas 25~45vol%, residual H
_The raw material gas composed of _two carrier gases is supplied at 5500 / min.
ml in a CVD furnace, and a film forming pressure of 2.7k to 13.k.
By reacting under the conditions of 3 kPa and a film formation temperature of 750 to 1000 ° C., Ti and Z having a predetermined thickness are formed.
Various titanium zirconium carbonitride films composed of r, C, N, and O were formed. Subsequently, the film formation temperature 750 to 1000
The raw material gas was ZrCl ₄ gas: 1.5 vol%, C
H ₃ CN gas: 1.0vol%, 1.0vol%, a mixed gas of CO gas and CO ₂ gas, _{N 2} gas: 45 vol
%, And a source gas composed of the remaining H ₂ carrier gas is flowed into the CVD furnace at a rate of 6000 ml / min.
A zirconium oxycarbonitride layer was formed at 0 kPa. The multilayer structure having the titanium zirconium oxynitride layer and the zirconium oxycarbonitride layer as one set is defined as one unit layer, and three sets of multilayer structure unit layers are laminated to form a titanium oxycarbonitride having a total thickness of 9 μm. Sample numbers 29 to 39 were formed by forming a multilayer film composed of a zirconium layer and a zirconium carbonitride layer. Table 4 shows the structure of the titanium zirconium carbonitride oxide layer, the Zr content, the oxygen content, the maximum surface of the X-ray diffraction intensity ratio PR, and the cutting life for the sample numbers 30 to 39. The oxygen content of the titanium zirconium carbonitride layer was about 1.6% by mass. For comparison, as Comparative Example 40, a pair of a titanium nitride film having a thickness of 0.4 μm, a titanium carbonitride film having a thickness of 1 μm, a titanium carbonitride oxide layer and a zirconium carbonitride oxide layer were formed on a substrate. The multi-layered structure as one unit layer
By stacking the sets, a sample of a titanium carbonitride layer and a zirconium carbonitride layer having a total thickness of 9 μm was also prepared.

[0048]

[Table 4]

As shown in Table 4, when the zirconium content of Sample Nos. 30 to 38 is 0.3 to 50% by mass, the continuous cutting life is as long as 18 minutes or more, and the sample Nos. 30 to 36 are 1 to 40%.
In mass%, the continuous cutting life is further increased to 20 minutes or more, and in 5 to 30 mass% of Sample Nos. 31 to 35, the continuous cutting life is maximized to 22 minutes or more, and the cutting durability is most excellent. You can see that. In the present invention, it is essential to contain zirconium in the titanium zirconium carbonitride layer, but the content is 0.3 to 50% by mass, more preferably 1 to 40% by mass, and still more preferably 5 to 50% by mass.
-30% by mass. In Comparative Example 40, wear progressed probably because the hardness was relatively low, and the continuous cutting life was 1
One minute. When the number of units is compared with three sets, sample number 2
The sample No. 9 has a continuous cutting life of 16 minutes, which is about 1.5 times longer than that of Comparative Example 40, and the tool life of the product of the present invention coated with a unit layer composed of a titanium zirconium oxynitride layer and a zirconium oxycarbonitride layer. Has a tool life of about 1.10 compared to the sample of Comparative Example 40 in which a unit layer comprising a titanium oxycarbonitride layer containing no zirconium and a zirconium oxycarbonitride layer is coated.
It was found to be 5 times or more superior.

Example 3 The same cutting as in Example 1 was carried out to clarify the effect on the tool life of a multilayer film comprising a unit layer of a titanium zirconium carbonitride and a zirconium carbonitride in the present invention. After a titanium nitride film having a thickness of 0.4 μm was formed on a cemented carbide substrate for a tool, a titanium carbonitride film having a thickness of 1 μm was formed. Next, a titanium zirconium carbonitride oxide layer was formed directly thereon under the same conditions as those of Sample Nos. 5 to 13 in Example 1. Subsequently, a film formation temperature was 900 ° C., and a raw material gas was ZrCl ₄ gas: 1.5 vol%. CH ₃ CN gas: 1.0vol%, 0.5~2.5vol% a mixed gas of CO gas and CO ₂ gas, _{N 2} gas: 45 vol%,
The source gas composed of the remaining H ₂ carrier gas is reduced to 6 per minute.
Flow only 000 ml into the CVD furnace, and deposit pressure: 5.0k
A zirconium carbonitride layer was formed at Pa. The multi-layered structure comprising the titanium zirconium oxynitride layer and the zirconium oxycarbonitride layer as one set is defined as one unit layer, and 15 sets of multi-layered structure unit layers are laminated to form a titanium oxycarbonitride having a total thickness of 9 μm. A multilayer film composed of a zirconium layer and a zirconium oxycarbonitride layer was formed, and sample numbers 40 to 49 were obtained. Table 5 shows the structure of the titanium zirconium carbonitride oxide layer, the oxygen content, the maximum surface of the X-ray diffraction intensity ratio PR, and the cutting life for the sample numbers 40 to 49. In each case, the zirconium content in the titanium zirconium carbonitride layer was about 10% by mass. Further, as Comparative Example 50, a thickness of 0.4
A 3 μm-thick titanium nitride film, a 1 μm-thick titanium carbonitride film, a zirconium carbonitride layer, and three layers each including a titanium zirconium carbonitride layer as one unit layer were provided, and a sample having a total thickness of 9 μm was also manufactured.

[0051]

[Table 5]

In Table 5, when the oxygen content in the multilayer film of Sample Nos. 40 to 47 is 0.05 to 10% by mass, the continuous cutting life is as long as 22 minutes or more, and that of Sample Nos. 40 to 44 is 0.3. ~
At 5% by mass, the continuous cutting life is further extended to 24 minutes or more, and at 0.3 to 3% by mass of sample numbers 40 to 43, the continuous cutting life is the longest at 26 minutes or more, and the cutting durability characteristics are the most. It turns out that it is excellent. Further, in the example of Comparative Example 50 in which three sets of unit layers were provided, abrasion progressed because the columnar crystal form of the film was weak and crack resistance was relatively poor, and the continuous cutting life was 12 minutes. This means that the sample of Sample No. 17 (oxygen amount 0.05 mass%) having three units of the present invention and a sample number of 17 (oxygen amount 0.05 mass%) has a continuous cutting life of 18 minutes, about 1.5 times longer, Example 29 in which the tool life of the present invention coating a unit layer composed of a zirconium carbonitride layer and a unit layer composed of an oxygen-free titanium zirconium carbonitride layer and a zirconium carbonitride layer was compared. It was found that the tool life was about 1.5 times or more superior to that of the sample.

(Example 4) Tool life when a unit layer having a multilayer structure comprising a titanium zirconium carbonitride layer and a zirconium carbonitride layer in the product of the present invention is formed immediately above the titanium carbonitride oxide layer. To clarify the impact on
On the same cemented carbide substrate for a cutting tool as in Example 1, a thickness of 0.4
After forming a titanium nitride film having a thickness of μm, 1.5 vol% of TiCl ₄ gas, 2.0 vol% of CH ₃ CN gas, and C
1.0 vol% of a mixed gas of O gas and CO ₂ gas, N ₂ gas
A source gas composed of 45 vol% of gas and the remaining H ₂ carrier gas was flowed into the CVD furnace at 5500 ml / min.
At a pressure of 6.6 kPa and a film forming temperature of 850 ° C., a thickness of 1
A μm-thick titanium carbonitride film was formed. Then, immediately above it, 15 sets of unit layers composed of a titanium zirconium carbonitride layer and a zirconium carbonitride layer were formed under the same conditions as sample No. 7 of Example 1 to form a coating having a total thickness of 9 μm.
It was set to 1. Further, after forming a titanium nitride film having a thickness of 0.4 μm on a cemented carbide substrate under the same film forming conditions as sample number 51, directly forming a titanium carbonitride oxide film or a titanium carbonitride film, , 15 sets of unit layers composed of a titanium zirconium carbonitride layer and a zirconium carbonitride layer, having a total thickness of 10 μm
Was formed, and this was designated as Sample No. 52. Table 6 summarizes the structure, the zirconium content, the oxygen content, the maximum surface of the X-ray diffraction intensity ratio PR, and the continuous cutting life of the titanium zirconium carbonitride layers of Sample Nos. 51 and 52.

[0054]

[Table 6]

For comparison, a titanium nitride film having a thickness of 0.4 μm and a titanium carbonitride film having a thickness of 1 μm were similarly formed on a substrate made of a cemented carbide for a cutting tool. Comparative Example 53 having a total thickness of 9 μm was produced by coating with a zirconium film. The results of the test are also shown in Table 6.

From Table 6 and Sample No. 7 in Example 1, Sample No. 51 has a continuous cutting life of 28 minutes compared to Sample No. 52 in which the unit layer of the present invention is formed immediately above the titanium nitride film. It can be seen that the continuous cutting life was as excellent as 20 minutes. In Comparative Example 53, the flank wear rapidly increased, the continuous cutting life was as short as 4 minutes, and the tool life was inferior to that of the present invention.

(Example 5) The titanium zirconium oxycarbonitride layer in the unit layer of the multilayer structure composed of the titanium zirconium carbonitride oxide layer and the zirconium carbonitride layer according to the present invention is as follows:
In order to clarify the effect on the tool life when the columnar structure and the granular structure are elongated in the film thickness direction, a titanium nitride film having a thickness of 0.4 μm was formed on the same cemented carbide substrate for a cutting tool as in Example 1. After forming the film, a titanium carbonitride film having a thickness of 1 μm was formed. Next, a film forming temperature of 1050 ° C. and a source gas of TiCl
₄ Gas: 1.5vol%, ZrCl ₄ gas: 1.5vo
l%, CH ₄ gas 2.5 vol%, _{N 2} gas: 45Vo
1%, mixed gas of CO gas and CO ₂ gas: 1.0 vol
%, And a source gas composed of the remaining H ₂ carrier gas is flowed into the CVD furnace at a rate of 6000 ml / min.
A titanium carbonitride zirconium layer was formed at 0 kPa.
Subsequently, the film forming temperature was 1050 ° C., and the source gas was ZrCl ₄ gas: 1.5 vol%, CH ₄ gas: 1.0 vol%, N
A source gas composed of ₂ gases: 45 vol% and the remaining H ₂ carrier gas was flowed into the CVD furnace at a rate of 6000 ml / min, and a zirconium carbonitride layer was formed at a film forming pressure of 5.0 kPa. The multi-layered structure including the titanium zirconium oxynitride layer and the zirconium carbonitride layer is a set of unit layers, and the titanium zirconium oxycarbonitride layer and the zirconium carbonitride having a total thickness of 9 μm, each including 15 sets of unit layers. A film composed of the layers was formed to obtain Sample No. 54.

The structure of Sample No. 54 is granular, having a zirconium content of 10.0% and an oxygen content of 1.2.
%, The maximum plane of the X-ray diffraction intensity ratio PR is (220),
The continuous cutting life was 16 minutes.

Further, when comparing Sample No. 54 with Sample No. 7, it is found that the titanium zirconium carbonitride zirconium layer in the unit layer having the multilayer structure composed of the titanium zirconium carbonitride and zirconium carbonitride layers is elongated in the film thickness direction. It can be seen that the continuous cutting life is longer and superior in the case of a columnar structure (sample No. 7, continuous cutting life of 28 minutes) than in the case of not having an elongated columnar structure (sample number 49, continuous cutting life of 16 minutes).

Embodiment 6 In the present invention, in order to investigate the influence of the difference in the plane where the equivalent X-ray diffraction intensity ratio PR of the titanium zirconium carbonitride oxide layer constituting the unit layer shows the maximum, a unit layer having a multilayer structure was used. The film forming temperature when forming the titanium zirconium carbonitride oxide layer is 950 ° C. (Sample No. 55), 1000 ° C. (Sample No. 56), 1050 ° C.
A coated tool of the present invention having 15 sets of unit layers was produced in the same manner as in Example 1 except that the sample was changed to (Sample No. 57). The structure, zirconium content, and oxygen content of the titanium zirconium carbonitride oxide layers of the obtained sample numbers 55 to 57,
Table 7 summarizes the maximum surface and the continuous cutting life of the X-ray diffraction intensity ratio PR.

[0061]

[Table 7]

From Table 7, the equivalent X-ray diffraction intensity ratio PR of the titanium zirconium carbonitride oxide layer in the unit layer of the present invention is as follows:
It can be seen that the continuous cutting life is longer and superior when the (422) plane or the (311) plane is the maximum than when the (111) plane and the (220) plane are the maximum. Also,
It can also be seen that the continuous cutting life is longer and better when the (111) plane is maximum than when the (220) plane is maximum.

[0063]

As described above, according to the present invention, titanium zirconium oxycarbonitride having excellent balance of oxidation resistance, crack resistance and abrasion resistance of the film, and remarkably excellent tool life, as compared with the prior art. A multilayer coated tool having a layer and a zirconium carbonitride or zirconium carbonitride layer can be realized.

[Brief description of the drawings]

FIG. 1 is an example of a micrograph showing the structure of a ceramic material of a multilayer coated tool according to an example of the present invention.

FIG. 2 shows an example of an X-ray diffraction pattern of the multilayer coated tool of the present invention.

FIG. 3 is a view showing an example of an equivalent X-ray diffraction intensity ratio PR of a titanium zirconium carbonitride film of the multilayer coated tool of the present invention.

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 3C046 FF10 FF11 FF16 FF22 4K030 AA03 AA09 AA14 AA17 AA18 BA18 BA22 BA35 BA41 BB01 BB12 CA02 CA03 CA18 FA10 JA09 JA10 LA22

Claims (7)

[Claims] 1. A multi-layer structure comprising a titanium zirconium carbonitride layer and a zirconium carbonitride layer, and / or a unit structure layer comprising a titanium zirconium carbonitride layer and a zirconium carbonitride layer. A multi-layer coated tool comprising a unit layer, wherein the unit layer is coated on a tool base body at least one unit layer or more. 2. The multi-layer coated tool according to claim 1, wherein at least one unit layer of the multilayer structure has a zirconium carbonitride layer or a zirconium carbonitride layer formed on the titanium zirconium oxide carbonitride layer. A multilayer coated tool characterized by being constituted. 3. The multi-layer coated tool according to claim 1, wherein the zirconium content of the titanium zirconium oxycarbonitride film forming at least one set of unit layers of the multilayer structure or one set of unit layers is 10% by mass. % Or less. 4. The multi-layer coated tool according to claim 1, wherein at least one unit layer of said multilayer structure or a titanium zirconium carbonitride film forming one set of unit layers is formed. A coated tool, wherein the oxygen content in the film is 10% by mass or less. 5. The multilayer coated tool according to claim 1, wherein at least one titanium zirconium oxycarbonitride layer in the unit layer is from the (422) plane or the (311) plane. A multilayer coated tool, wherein the equivalent X-ray diffraction intensity ratio PR is maximum. 6. The multi-layer coated tool according to claim 1, wherein at least one titanium zirconium carbonitride in the unit layer has a columnar structure elongated in a film thickness direction. Multi-layer coated tool. 7. A multi-layer coated tool according to claim 1, wherein at least one of said unit layers is formed directly on a titanium carbonitride layer or a titanium carbonitride layer. A multi-layer coated tool characterized by the following.