JPH10156606A - Aluminum oxide coating tool and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aluminum oxide coating tool of stable quality in a cutting characteristic or the like, by increasing adhesion of both interfaces of a connection layer, provided between an oxidized film mainly composed of α type aluminum oxide and a non-oxidized film which is a bed (base unit side film) thereof to come into direct contact with both the films, or mechanical strength of the connection layer itself and mechanical strength of the oxidized film itself mainly composed of the α type aluminum oxide. SOLUTION: In an aluminum oxide coating tool formed in a base unit surface with a single layer skin film of any one kind of carbide, nitride, carbide nitride, oxide, oxide carbide, oxide nitride and oxide carbide nitride of IVa, Va, VIa group metal in the periodic table or a multi-layer skin film consisting of two or more kinds and an oxidized film composed mainly of α type aluminum oxide of at least one layer, the strongest peak surface of X-ray diffraction of the oxidized film is a surface 110.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting and wear-resistant aluminum oxide-coated tool and a method for producing the same.

[0002]

2. Description of the Related Art In general, a coated tool is produced by forming a hard film on a substrate made of a super-hard alloy, high-speed steel or special steel by a chemical vapor deposition method or a physical vapor deposition method.
Such a coated tool has both the wear resistance of the film and the toughness of the substrate, and is widely used in practice. In particular, when cutting high-hardness materials at high speed, it is necessary to raise the cutting edge temperature of the cutting tool to around 1000 ° C. and to withstand mechanical shocks such as abrasion due to contact with a work material and intermittent cutting, and the like. Coated tools having both strength and toughness are useful.

The hard coating includes a non-oxidized film made of carbides, nitrides and carbonitrides of Group IVa, Va and VIa metals excellent in wear resistance and toughness and an oxide film excellent in oxidation resistance. Used as a single-layer or multilayer film. For example, TiC, TiN, and TiCN are used for the non-oxide film, and α-type aluminum oxide and κ-type aluminum oxide are particularly used for the oxide film. The disadvantage of non-oxide films made of carbides, nitrides, carbonitrides, etc. is that they are easily oxidized. To compensate for this disadvantage, an oxide film such as aluminum oxide with excellent oxidation resistance is formed on the non-oxide film. It has been practiced to prevent a non-oxidized film from being oxidized by having a multilayer film structure.

The disadvantage of the non-oxide / oxide film multilayer structure is that the adhesion between the non-oxide film and the oxide film is low, or the mechanical strength is not stable at high temperatures. When a κ-type aluminum oxide film is used as the oxide film, the κ-type aluminum oxide has an advantage that it has relatively good adhesion to the non-oxide film and can be formed at a relatively low temperature of 1000 to 1020 ° C. However, since it is a metastable alumina, it is transformed into α-type aluminum oxide when used at a high temperature, so that its volume changes, cracks occur in the film, and the film peels off. In contrast, when α-type aluminum oxide is used as the oxide film, this α-type aluminum oxide is an alumina film that is stable even at high temperatures and has an advantage of excellent high-temperature characteristics, but is directly formed on a non-oxide film. In order to achieve this, it is necessary to form a film at a high temperature, and there is a disadvantage that the crystal grain size of the α-type aluminum oxide increases and the mechanical properties deteriorate.

For this reason, conventionally, a method of obtaining an α-type aluminum oxide at a relatively low temperature of 1000 to 1020 ° C. by oxidizing the surface of the non-oxide film to form a base point for forming an oxide film and then forming aluminum oxide. It is commonly used. FIG. 4 schematically shows the vicinity of the interface between such a non-oxide film and the oxide film, and shows the relationship between the non-oxide film 3 formed on the substrate side and the oxide film 1 mainly composed of α-type aluminum oxide. Indicates the bonding layer 2. As described above, the bonding layer 2 is generally produced by oxidizing the surface of the non-oxide film 3, and its thickness is as thin as 1 μm or less. For this reason, at first glance, it appears that the oxide film 1 is directly formed on the non-oxide film 3. However, in the present invention, the oxide layer formed on the non-oxide film 3 is used to clarify its function and characteristics. Regardless of the production method, they are all described as the bonding layer 2.

As described above, the oxide film 1 mainly composed of α-type aluminum oxide formed after the bonding layer 2 is formed by oxidizing the surface of the non-oxide film 3 has insufficient adhesion strength. In some cases, an accident may occur in which the non-oxide film 3 serving as the base is peeled off at an early stage. Therefore, various methods have been devised for forming the bonding layer 2 in order to increase the adhesion strength between the oxide film 1 mainly composed of α-type aluminum oxide and the non-oxide film 3 formed on the substrate side. For example, Japanese Unexamined Patent Publication No.
In 316758, in order to improve the cutting performance for cast iron, after forming a TiCN layer (3 in FIG. 4) on the base, an H ₂ carrier gas having an oxidation potential of less than 20 ppm of H ₂ O is used, and CO ₂ , The nucleation of alumina was started by sequentially supplying the reaction gas in the order of CO and AlCl ₃ , the temperature at the time of nucleation was set to about 1000 ° C., and an α-alumina film was formed. An alumina layer having an equivalent X-ray intensity TC (012) of more than 1.3 has been proposed. In this case, the oxidation potential is first set to 20 pp of H ₂ O on the surface of the TiCN layer (3 in FIG. 4).
H ₂ carrier gas and CO ₂ gas at a concentration of less than m,
By flowing CO gas, the surface of the TiCN layer is oxidized to form a bonding layer (2 in FIG. 4).
It is considered that an α-alumina film was formed by further adding AlCl ₃ and flowing.

[0007] In order to improve the wear resistance and fracture resistance of aluminum oxide itself, H ₂ during deposition of the alumina
By using a reaction gas to which S gas and SO ₂ gas are added (JP-A-06-31503) or by further using ₂₀ to 30% by volume of CO ₂ in addition to H ₂ S gas and SO ₂ gas (Japanese Patent Laid-Open No. -108405), the X-ray diffraction peak intensity I (0) of the (030) plane which is the main peak.
X-ray diffraction peak intensities I (10) of (30) and (104) planes
4) and I (030) / I (104)> 1, or in addition, the X-ray diffraction peak intensity I (012) of the (012) plane is I (012) / I (030)> 1. An aluminum oxide having a crystal structure mainly composed of an α-type crystal having the following relationship has been proposed.

[0008]

SUMMARY OF THE INVENTION The present inventors conducted a cutting test on a cutting tool produced by forming a multilayer film containing an oxide film mainly composed of α-type aluminum oxide on a substrate such as a carbide substrate, and found that the cutting tool was damaged. As a result of detailed evaluation of the portion, as described above, the oxide film 1 mainly composed of α-type aluminum oxide was peeled off from the bonding layer portion (2 in FIG. 4) at the interface with the non-oxide film 3 as the base, It was found that the film itself had cracks and crystal grains were falling off. The problem to be solved by the present invention is that the bonding layer 2 which is between the oxide film 1 mainly composed of α-type aluminum oxide and the non-oxide film 3 which is the base (film on the substrate side) and is in direct contact with both films. Adhesion of both interfaces or bonding layer 2
An object of the present invention is to provide an aluminum oxide-coated tool with stable quality such as cutting characteristics by increasing the mechanical strength of itself and the mechanical strength of the oxide film 1 mainly composed of α-type aluminum oxide.

Generally, the bonding layer 2 is made of TiC, TiN,
The surface of the non-oxide film 3 made of TiCN film or the like between H ₂ O and CO ₂
However, it is difficult to stably produce an oxide film-coated tool mainly composed of high-quality α-type aluminum oxide as described below.
That is, when the concentration of the oxidizing gas such as CO ₂ is high during the formation of the bonding layer 2, Ti ₂ O ₃ (X-ray pattern
No. 10-63 reference) and Ti ₃ O ₅ (ASTMNo.1
1-217) or TiO ₂ (ASTM file N
o. 21-1276), the adhesion strength to the base is low, the oxide layer (bonding layer) itself is brittle, and the mechanical strength is low. On the other hand, when the concentration of the oxidizing gas due to CO ₂ or the like is reduced to oxidize the non-acidic lower film 3 so that Ti ₂ O ₃ , Ti ₃ O ₅ , and TiO ₂ are not formed, the underlying TiC,
Oxidation of the surface of the non-oxidized film 3 such as TiN or TiCN becomes insufficient. When the film forming temperature of aluminum oxide is 1020 ° C. or less, κ-type aluminum oxide is formed and α-type aluminum oxide is not formed stably. When the film forming temperature of aluminum is set to 1030 ° C. or more, the grain size of the oxide film 1 mainly composed of α-type aluminum oxide becomes coarse, and the center line average surface roughness Ra and the maximum surface roughness Rmax also become rough, so that the coating tool becomes harder. A disadvantage occurs in that the characteristics are deteriorated.

Further, as described above, the non-oxide film
Is not oxidized to form the bonding layer 2, but the bonding layer 2 of TiCO, TiNO, TiCNO, etc. is formed on the non-oxidized film 3.
The following has been proposed as a method for newly forming a film. In JP-A-63-195268, a 0.5 μm-thick TiCNO film is used as the inner layer of the alumina film as the bonding layer 2 shown in FIG.
A film is formed at 1100 ° C. or 1030 ° C., and then an alumina film 1 is formed at 960 ° C. and 1000 ° C., respectively.
After an O film or a TiCNO film is formed as the bonding layer 2 in FIG. 4, the alumina film 1 is formed. Also, Japanese Patent Application Laid-Open No. 05-3
No. 45976, a film thickness of 0.5 μm and 3 μm and a particle size of 0.2
TiCl the TiCNO film or TiCO film of ~1.5μm ₄
And CO, H ₂ , N ₂ gas to form a bonding layer 2 of 1000
After the film formation at 1000 ° C., the alumina film 1 is formed at 1000 ° C. The features of the conventional example in which these bonding layers 2 are formed separately are that the film forming temperature of the bonding layer 2 is higher than the film forming temperature of the alumina film (Japanese Patent Laid-Open No. 63-195268). Is as thick as 1 μm (JP-A-02-30406)
) And the use of a CO gas at the time of forming the bonding layer 2 (Japanese Patent Application Laid-Open No. 05-345976). If the oxidizing gas such as CO ₂ or H ₂ O is too large or the film forming temperature is too high during the formation of the bonding layer 2, the oxygen content in the bonding layer 2 will be too large, and the base The adhesive strength with the non-oxide film 3 is reduced, and the mechanical strength of the bonding layer 2 itself is lowered. When the thickness of the bonding layer 2 is as thick as 1 μm, the mechanical strength of the oxide film itself constituting the bonding layer is reduced. When the CO gas is used instead of the CO ₂ gas, the oxygen content in the bonding layer 2 becomes insufficient, and the oxide film 1 mainly composed of α-type aluminum oxide becomes stable. The disadvantage that it could not be formed appeared. As described above, an object of the present invention is to improve the adhesion and mechanical strength characteristics of the thin bonding layer 2 that bonds the underlying non-oxide film 3 and oxide film 1 to each other.
Provided is a long-life aluminum oxide-coated tool having an oxide film 1 mainly composed of α-type aluminum oxide having good adhesion to a non-oxide film 3 and having a small particle size and excellent mechanical strength, and a method for manufacturing the same. It is.

[0011]

Means for Solving the Problems The inventors of the present invention have made intensive studies based on the above findings, and have found that TiC and Ti
By modifying the thin bonding layer 2 formed between the non-oxide film 3 of N, TiCN or the like and the oxide film 1 mainly containing α-type aluminum oxide, the non-oxide film 3 and α-type aluminum oxide are mainly used. The adhesiveness with the oxide film 1 is improved, the X-ray peak intensity of the (110) plane of the oxide film 1 mainly containing α-type aluminum oxide is increased, and the crystal of the oxide film 1 mainly containing α-type aluminum oxide is increased. The present inventors have found that by reducing the particle size, mechanical properties are improved and the above-mentioned problems are solved, and the present invention has been reached.

That is, according to the present invention, the surface of the base
Group IVa, Va, VIa group metal carbides, nitrides, carbonitrides,
Oxide, oxycarbide, oxynitride and oxycarbonitride are formed of any one type of single-layer film or a multi-layer film composed of two or more types thereof, and at least one oxide film mainly composed of α-type aluminum oxide. In the aluminum oxide-coated tool, the strongest X-ray diffraction peak plane of the oxide film is (110).
An aluminum oxide-coated tool characterized by being a surface. In addition, on the surface of the substrate, carbides, nitrides, carbonitrides, oxides, oxycarbides of metals belonging to groups IVa, Va and VIa of the periodic table,
In an aluminum oxide-coated tool in which an oxynitride and an oxycarbonitride are a single layer coating or a multilayer coating composed of two or more kinds thereof, and at least one oxide film mainly composed of α-type aluminum oxide, Equivalent peak intensity PR (1) by (110) plane of X-ray diffraction of the oxide film
10) is not less than 1 and preferably not less than 1.5. In addition, the α
The thickness of the oxide film mainly composed of aluminum oxide is 2.5μ
m, the average particle size of the oxide film is 2 μm or less;
When the film thickness is 2.5 μm or more, the average particle size is 4 μm or less. Further, the oxide film mainly composed of the α-type aluminum oxide has a center line average surface roughness Ra of 0.6 μm or less, preferably 0.5 μm or less, and a film of the oxide film. Maximum surface roughness Rm of the oxide film when the thickness is less than 2.5 μm
a is 2 μm or less, and the maximum surface roughness Rmax when the film thickness is 2.5 μm or more is 3 μm or less. Also, the lattice stripes of the oxide film mainly composed of α-type aluminum oxide (1 in FIG. 4) and the bonding directly contacting the oxide film mainly composed of α-type aluminum oxide so as to increase the adhesion between the respective films. It is characterized in that lattice fringes of the layer (2 in FIG. 4) are continuous at the interface. Here, the lattice fringe means a transmission electron microscope (TEM).
Means a stripe pattern of a lattice image obtained when the crystal is observed at a high magnification. When trying to take a lattice image of two or more adjacent films (crystals), the lattice images of both crystals are simultaneously observed only when the crystal orientations of these films are almost parallel to the incident beam of the transmission electron microscope. Is done. The fact that the lattice fringes of the oxide film 1 mainly composed of α-type aluminum oxide and the lattice fringes of the coupling layer 2 are continuous at the interface means that the crystal orientations of both crystals are substantially parallel to the incident beam, and α
This shows that both the oxide film 1 mainly composed of aluminum oxide and the bonding layer 2 have an epitaxial relationship. When the crystal orientations of both films are not parallel and only one crystal orientation is parallel to the incident beam of the transmission electron microscope, a lattice image of only that crystal is obtained, and a lattice image of the other non-parallel crystal is obtained. I can't. In addition, even if the crystal orientations of both crystals are parallel, if both crystals are not in direct contact with each other and another substance is interposed, the lattice image of both crystals will be lattice fringes due to inclusions between those obtained. Are interrupted on the way, and the lattice fringes are not continuous. Further, the present invention is characterized in that a titanium nitride film is formed on the surface of an oxide film mainly composed of α-type aluminum oxide. Further, the present invention relates to IV of the periodic table.
An oxidation characterized by using, as a base, a super-hard alloy comprising at least one of carbides, nitrides and carbonitrides of a, Va and VIa group metals and at least one of Fe, Ni, Co, W, Mo and Cr. It is an aluminum coated tool.

Further, the production method of the present invention provides a method of preparing
A non-oxide film layer made of one or more of carbides, nitrides, and carbonitrides of Group a, Va, and VIa metals, and a gas composition used for forming the non-oxide film layer are mainly used. An oxide, oxycarbide, or oxynitride of a Group IVa, Va, or VIa metal of the periodic table formed by adding an oxidizing gas of 1 to 5 vol%, preferably 0.5 to 3 vol%, and forming a film at a film forming temperature of 950 to 1020 ° C. And a bonding layer formed of a combination of a thin layer of one or more of oxycarbonitrides, and an oxide film mainly composed of α-type aluminum oxide formed thereon. This is a method for producing an aluminum oxide-coated tool.

[0014]

FIG. 1 shows an example of an X-ray diffraction pattern measured by a 2θ-θ scanning method using a coating portion of an aluminum oxide-coated tool of the present invention as a sample surface. The X-ray source is Cu Kα1 (wavelength λ = 1.54).
05A) was used. In the present invention, TiN and TiCN are formed on the substrate surface in the same manner as the conventional product, then a thin TiC layer is formed, and CO ₂ gas is further added to the constituent gas used for forming the TiC continuously. After forming a TiC layer / TiCO layer by forming a TiCO layer by reacting with each other, α-type aluminum oxide is formed on the surface of the bonding layer. In the drawing, only the X-ray peak of α-Al ₂ O ₃ is shown as a peak surface, and the peak names of peaks (for example, TiCN or the like) due to other forming compounds are not shown.
As shown in FIG. 1, the product of the present invention has an X-ray peak of α-Al ₂ O ₃ (1
10) The plane shows a stronger peak than the other peaks, and (01)
2) The intensity of the peak or (030) peak is weak, and (11)
It can be seen that the peak intensity does not exceed 0). α-Al ₂
In order to quantitatively evaluate the X-ray peak intensity from the (hkl) plane of O _3, the equivalent peak intensity PR (hkl) and TC (hkl) based on the (hkl) plane were defined by the following equation. Here, I (hkl) represents the X-ray diffraction intensity at the time of actual measurement by the (hkl) plane, and I ₀ (hkl) represents the ASTM file N
o. 10-173 (Power Diffract
ion File Published by JCP
DS International Center f
or Diffraction Data), and indicates the X-ray diffraction intensity from the (hkl) plane of powder particles having isotropic orientation. T
C (hkl) is the same as that defined in JP-A-06-316758, and PR (hkl) further includes (124) and (03)
The same definition is made including the peak of 0). PR (hkl) and TC (hkl) are both AST
X from the (hkl) plane of the film measured by X-ray diffraction with respect to the X-ray peak intensity of the isotropic particles described in the data of M
Shows the relative intensity of the X-ray diffraction peak intensity, and PR (hk
l), the larger the value of TC (hkl) is, the stronger the X-ray peak intensity from the (hkl) plane is than the other peak intensities.
1) Indicates that the measurement sample is oriented in the direction. PR (hkl) = {I ( hkl) / I 0 (hkl)} / [Σ
{I (hkl) / I ₀ (hkl)} / 8 where (hkl) = (012), (104), (11
0), (113), (024), (116), (12
4), (030) TC ( hkl) = {I (hkl) / I 0 (hkl)} / [Σ
{I (hkl) / I ₀ (hkl)} / 6] (hkl) = (012), (104), (11
0), (113), (024), (116) Specifically, the PR (110) in FIG. 1 is 5.04,
The X-ray peak intensity of (110) in FIG. 1 is 5.04 times stronger than the (110) X-ray peak intensity of the powder particles. When 2θ is in the range of 20 to 80 °, in addition to the above eight peaks, (006), (202), and (21)
Although peaks 1), (122), and (018) also exist, these peak intensities have an I ₀ of 10 or less, and a small change in the peak intensity I greatly changes I / I _0, so that PR (hk)
l), not included in the calculation of TC (hkl).

The average crystal grain size on the surface of the oxide film of the product of the present invention was measured by a scanning electron microscope (S-2300) manufactured by Hitachi, Ltd.
Measured when the film thickness is less than 2.5 μm, 2
μm or less, and 4 μm when the film thickness is 2.5 μm or more.
It was below. The center line average surface roughness Ra is 0.6 μm.
m or less, and the maximum surface roughness Rmax was 2 μm or less when the thickness of the oxide film was less than 2.5 μm, and 3 μm or less when the thickness of the oxide film was 2.5 μm or more.

The vicinity of the interface between the oxide film mainly composed of α-type aluminum oxide, which is an example of the product of the present invention, the TiC / TiCO bonding layer which is in direct contact with the present oxide film, and the TiCN film thereunder is shown in FIG. ) Hitachi transmission electron microscope (H-
Observation by 9000 UHR) confirmed that lattice fringes were continuous at each interface between the films as shown in FIG. 3 described later. FIG. 5 schematically shows the continuity of the lattice fringes. FIG. 5 is provided only to explain the film formation state at the atomic level described below. Regarding the continuity of the lattice fringes at each interface, a slight shift (mismatch) between the lattice fringes is allowed. It goes without saying that the continuity of the lattice fringe, the lattice fringe interval, the number and the like are not limited to those shown in FIG.

The reason why the oxide film mainly comprising α-type aluminum oxide of the present invention is excellent in adhesion and mechanical properties is not clear, but the following may be considered. As shown in FIG. 1, the oxide film mainly containing α-type aluminum oxide of the present invention has a strong peak intensity in the (110) plane at the time of X-ray diffraction, and the (110) plane of the α-type aluminum oxide is parallel to the base material. Are strongly oriented. When manufactured by the manufacturing method of the present invention, an underlying non-oxide film (3 in FIG. 4), a bonding layer (2 in FIG. 4), and an oxide film mainly composed of α-type aluminum oxide (1 in FIG. 4)
In other words, an epitaxial relationship is established between the films, that is, each film is continuously formed at the interface (lattice stripes are continuously formed), so that the (110) plane of the α-type aluminum oxide is strongly oriented in the plane, and It is considered that vacancies and large defects hardly occur at the interface between the underlying non-oxide film 3 and the bonding layer 2 and the oxide film 1, and the adhesion between the films is increased. In this sense, the continuity (epitaxial relationship) of the lattice fringes does not need to be established at all interfaces, and the continuity of the lattice fringes (epitaxial relation) is observed when the vicinity of the coupling layer is observed at a magnification of 50,000 with a transmission electron microscope. If there is a region in which the relationship (1) is recognized, the excellent operation and effect according to the present invention can be obtained. Ti used for the base in the present invention
Non-oxidized films (3 in FIG. 4) such as C, TiN, and TiCN, and a bonding layer (corresponding to 2 in FIG. 4, for example, TiC / TiC
O, TiN / TiNO, TiCN / TiCNO, etc. 2) have an fcc crystal structure, and it is considered that when these films grow epitaxially, the oxide film 3 mainly composed of α-type aluminum oxide is likely to be oriented in the (110) direction. Further, when the equivalent X-ray peak intensity PR (110) by the (110) plane is 1 or more, preferably 1.5 or more, it indicates an isotropically oriented α-type aluminum oxide which is usually measured in powder form. The (110) X-ray peak intensity (ie, the X-ray intensity described in ASTM file No. 10-173) of the product of the present invention is higher than that of (110).
The X-ray peak intensity is 1 or more times, preferably 1.5 times or more, and the (110) plane is oriented 1 time or more, preferably 1.5 times or more, and the adhesion is excellent for the above reason. I understand. In the present invention, when the (110) peak intensity is high, the (012) peak intensity and the (030) peak intensity tend to be relatively weak. PR (110)
When the intensity is approximately 1 or more, TC (012) is 1.3 or less, the intensity of PR (110) increases, the TC (012) value decreases, and near the PR (110) = 8, TC (012) decreases. (012) becomes about 0.1. PR (11
When (0) is 1 or more, the intensity ratio I (030) / I (104) between the (030) peak and the (104) peak is 0 to 9.97.
The intensity ratio I (012) / I (030) between the (012) peak and the (030) peak is 0.08 to 6
3.06 and the value fluctuated PR (110) and I (030)
No correlation with / I (104) or I (012) / I (030) was found. In this developed product, the (110) peak is particularly strong, the (030) peak and the (012) peak are relatively weak, and the intensity of the (030) peak and the (012) peak is large. Kaihei 07-1
It can be seen that this is essentially different from the alumina film of No. 08405.

When the non-oxide film, the bonding layer and the oxide film mainly containing α-type aluminum oxide are grown epitaxially by the method of the present invention, the oxide film mainly containing α-type aluminum oxide is grown at a relatively low temperature. A film can be formed with high adhesion.
Therefore, the average crystal grain size of the oxide film mainly composed of α-type aluminum oxide is 2 μm or less when the thickness of the oxide film is less than 2.5 μm, and 4 when the thickness is 2.5 μm or more.
μm or less, and the center line average surface roughness Ra of the oxide film is 0.6 μm or less, and the maximum surface roughness Rmax is 2 μm or less when the thickness of the oxide film is less than 2.5 μm and When the film thickness is 2.5 μm or more, it can be reduced to 3 μm or less. As described above, in the present invention, the grain size and the center line average surface roughness R of the oxide film mainly composed of α-type aluminum oxide
a) Since the maximum surface roughness Rmax is small, friction when used as a tool for cutting or the like is small, and wear and shedding of the film are reduced, and it is considered that excellent mechanical properties are obtained. For the same reason, the center line average surface roughness Ra of the film surface is 0.1.
The thickness is preferably 5 μm or less, and the wear and shedding of the oxide film mainly composed of α-type aluminum oxide are further reduced, and the tool characteristics are further improved.

Next, a method for producing a novel aluminum oxide-coated tool according to the present invention will be described. The present invention forms a non-oxide film (3 in FIG. 4) formed of one or more of carbides, nitrides, and carbonitrides of metals of groups IVa, Va, and VIa of the periodic table, First, IV of the periodic table
a gas comprising a thin non-oxidized layer made of one or more of carbides, nitrides, and carbonitrides of a, Va, and VIa group metals, and continuously forming the non-oxidized film as it is Is formed at a film formation temperature of 950 to 1020 ° C. by adding an oxidizing gas of mainly 0.1 to 3.0 vol% to form a bonding layer (2 in FIG. 4). An oxide film (1 in FIG. 4) mainly composed of aluminum oxide is formed. By forming a film in this manner, first, carbides, nitrides, and metals of Group IVa, Va, and VIa of the periodic table
By forming a thin non-oxide layer (2-2 in FIG. 4) made of one or more of carbonitrides, an epitaxial relationship with the non-oxide film 3 serving as a base can be easily obtained. A high adhesion is obtained between the layer 3 and the bonding layer 2, and a layer formed by continuously adding an oxidizing gas (2 in FIG. 4).
-1) Oxide film 1 mainly composed of α-type aluminum oxide
The feature of the manufacturing method according to the present invention is that an epitaxial relationship is easily obtained between the bonding layer 2 and the bonding layer 2 and the oxide film 1 and high adhesion is obtained. Coated tools can be manufactured. At this time, the amount of the oxidizing gas added in the middle to continuously form the film in the bonding layer is 0.1 to 5 vol% of the total gas flow rate.
Needs to be When the amount of the oxidizing gas is less than 0.1 vol%, the amount of oxygen on the surface of the bonding layer is small, so that κ-type aluminum oxide is easily formed on the bonding layer, and an oxide film mainly composed of α-type aluminum oxide can be stably formed. 5 vol%
Proceeds oxidation coupling layer exceeds the excessive Ti ₂ O _3, Ti
_{Since a} large amount of ₃ O ₅ , TiO ₂ or the like is formed, the mechanical strength of the bonding layer itself is reduced, and a defect that an oxide film mainly composed of α-type aluminum oxide is easily peeled in the bonding layer occurs. Also,
When the film formation temperature is lower than 950 ° C., a dense bonding layer cannot be formed and the film is liable to peel off. When the temperature exceeds 1020 ° C., the crystal grains of the bonding layer are coarse and oxidization proceeds excessively, and the film is liable to peel. Further, in the film formation of the α-type aluminum oxide of the present invention, an oxide film can be formed by using a gas such as AlCl ₃ , H ₂ , CO ₂ , H ₂ S, and it is necessary to use SO ₂ gas having high toxicity and corrosiveness. And the amount of CO ₂ gas is the normal flow rate 2
Since the film can be formed at 0 vol% or less, an oxide film mainly composed of α-type aluminum oxide can be stably formed.

The oxide film mainly composed of α-type aluminum oxide of the present invention is not necessarily required to be the outermost layer, and at least one titanium compound (for example, a TiN layer) is formed on the oxide film mainly composed of α-type aluminum oxide. Etc.).

A known film forming method can be applied to the coating method in the present invention. For example, a normal chemical vapor deposition method (thermal CVD) or a chemical vapor deposition method (P
ACVD) can be used. The application is not limited to cutting tools, but may be a wear-resistant material, a mold, a molten metal part or the like coated with a single-layer or multilayer hard film containing an oxide film mainly composed of α-type aluminum oxide. The oxide film is not limited to α-type aluminum oxide single phase, and if α-type aluminum oxide is mainly used, other oxides such as a mixed film of α-type aluminum oxide and κ-type aluminum oxide or γ-type aluminum oxide, The same effect can be obtained even with a mixed film of other aluminum oxides such as θ-type aluminum oxide, δ-type aluminum oxide, and χ-type aluminum oxide, or a mixed film of α-type aluminum oxide and other oxides such as zirconium oxide. Can be Note that the oxide film mainly containing α-type aluminum oxide of the present invention means a film containing 80 vol% or more of α-type aluminum oxide.

Next, the coated tool according to the present invention will be specifically described with reference to examples. However, it goes without saying that the present invention is not limited to the scope of these examples.

(Example 1) WC 72%, TiC 8%,
A carbide substrate for a cutting tool having a composition of (Ta, Nb) C11%, Co9% (% indicates weight%) is CV
D furnace, and the surface was coated with H ₂ by chemical vapor deposition.
Using a carrier gas, a TiCl ₄ gas, and a N ₂ gas as source gases, a 0.3 μm thick TiN is first formed at 900 ° C., and then a H ₂ carrier gas, a TiCl ₄ gas, and a CH ₃ gas are formed.
Using a CN gas as a source gas, a 6 μm thick TiCN film
After forming a non-oxidized film (3 in FIG. 4) by forming the film at 00 ° C., a H ₂ carrier gas, a TiCl ₄ gas and a CH ₄ gas are added at 950 to 1020 ° C. for a total of 2,200 m.
1 / min for 5 to 30 minutes to form a film first, and then continuously and further add 2.2 to 110 ml / min of CO ₂
By adding a gas and forming a film for 5 to 30 minutes, TiC
A TiC / TiCO bonding layer (2 in FIG. 4) in which the layer and the TiCO layer were thinly laminated was prepared. Thereafter, AlCl ₃ gas and H ₂ gas 2 l / min were generated by flowing a H ₂ gas at a flow rate of 310 ml / min and a HCl gas at 130 ml / min into a small cylinder packed with small pieces of Al metal and kept at 350 ° C. Flow 100 ml / min of CO ₂ gas into the CVD furnace and
By reacting at 10 to 1020 ° C., an aluminum oxide film (1 in FIG. 4) having a predetermined thickness was formed to produce a product of the present invention. No SO ₂ gas was supplied during the formation of the aluminum oxide film.

The X-ray diffraction of the prepared film was measured using a X-ray diffractometer (RU-300R, manufactured by Rigaku Corporation) in the range of 20 to 90 ° by 2θ-θ method. Only the Kα1 ray was used as the X-ray source, and Kα2 ray and noise were removed by software built in the apparatus, and the measurement was performed.

In Example 1, after the film was formed up to the TiC / TiCO bonding layer, the aluminum oxide film was formed at 1020 ° C. by flowing AlCl ₃ gas, H ₂ gas 2 l / min and CO ₂ gas 100 ml / min. FIGS. 1 and 2 show the results of two representative X-ray diffraction measurements. In the figure, X of α-Al ₂ O ₃ is shown.
Only the line peak is shown as a peak plane, and the peak names of other forming compound peaks (eg, TiCN) are not shown. 1 and 2, the α (110) peak is stronger and α (01)
It can be seen that peaks such as 2), α (104) and α (030) are small. In the case of FIG. 1, I (030) / I (104)
<1, I (012) / I (030)> 1, and in the case of FIG. 2, I (030) / I (104)> 1, I (012) / I
(030)> 1. Example 1 measured similarly
PR (110) and TC (012) and I
(030) / I (104), I (012) / I (030)
Table 1 summarizes the evaluation results.

[0026]

[Table 1]

The average particle diameter of the aluminum oxide film was taken on a SEM photograph of the surface of the aluminum oxide film at a magnification of 5000 times as shown in FIG. 6A (magnification on the photograph was 5000 × 0.8).
= 4000 times), and FIG. 6B corresponding to FIG.
SE with dimensions of 70 mm x 85 mm as shown in the schematic diagram of
16.5mm, 35mm, 52.5mm from above on M-photo
A total of five lines were drawn by connecting a straight line drawn in the lateral direction to each position and a diagonal line of the photograph, and the average particle size was determined from the number of crystal grains in each straight line by the following formula. Average particle size (μm) = (total length of straight line (mm)) / (total number of crystal grains in straight line (q)) × 0.25 FIGS. 6 (a) and 6 (b) show the above average particle size. The total length of the straight line is 475 mm, the total number of crystal grains in the straight line is 85, and the average crystal grain size is 1.4.
μm. The center line average surface roughness Ra of the surface of the aluminum oxide film is Veeco Instruments Inc.
c. The maximum surface roughness Rma was measured with a measuring length of 0.25 mm using a palpation type surface roughness meter DEKTAK8000 manufactured by the company.
x is a laser microscope 1L manufactured by Lasertec Inc.
The measurement length was 18 μm using M11. The aluminum oxide film thickness at that time was measured by taking a fractured surface of the sample whose surface roughness was measured in a SEM photograph at a magnification of 5000 times. By measuring Rmax at the above measurement length of 18 μm, measurement errors due to foreign substances and the like were suppressed, and the original Rmax of the alumina film could be measured. Table 1 summarizes the results of these evaluations.

According to Table 1, the product of the present invention has PR (110) of 1 or more and TC (012) of 1.3 or less.
(030) / I (104) and I (012) / I (030)
Means that there is no correlation with PR (110)
It can be seen that the values vary from 4.369 to 0.082 to 11.693 and are not consistent. Also, it can be seen that the ratio of particle size / film thickness slightly increases as PR (110) increases. Also, from Table 1, the average particle size of the product of the present invention is 2 μm or less when the thickness of the oxide film is less than 2.5 μm, and 4 μm or less when the thickness is 2.5 μm or more. The surface roughness Ra is 0.6 μm or less, and the maximum surface roughness Rmax is 2 μm or less when the thickness of the oxide film is less than 2.5 μm, and Rmax is 3 μm or less when the thickness of the oxide film is 2.5 μm or more. It can be seen that it is.

(Embodiment 2) In the procedure of the above-mentioned embodiment 1, the same procedure as that of the embodiment of FIG.
3 μm thick TiN at 900 ° C., 6 μm thick TiC
After forming the N film at 900C, a TiC / TiCO bonding layer was formed at 950-1010C. Then, AlCl ₃
The gas, ₂ l / min of H ₂ gas, 100 ml / min of CO ₂ gas and 8 ml / min of H ₂ S gas were flowed into a CVD furnace and 1010
Film of aluminum oxide at 4 ° C. and then 4 l of H ₂ gas
/ Min, 50 ml / min of TiCl ₄ gas and 1.3 l / min of N ₂ gas
7, 8 and 9 show the results of three representative X-ray diffraction measurements of the product of the present invention when a titanium nitride film was formed at 1010 ° C. by flowing the components. Table 2 summarizes the evaluation results of the product of the present invention according to Example 2.

[0030]

[Table 2]

7, 8, and 9, it can be seen that the peak of α (110) is strong and the peaks of α (012), α (104), α (030) are small. This relatively weak α (01
2), α (104) and α (030) peaks are shown in FIG.
In the case of I (030) / I (104) <1, I (012) /
I (030)> 1, and in the case of FIG. 8, I (030) / I
(104)> 1, I (012) / I (030) <1, and in the case of FIG. 9, I (030) / I (104)> 1, I
It can be seen that (012) / I (030)> 1.

According to Table 2, the product of the present invention in which an aluminum oxide film was formed using H ₂ S gas had PR (110) of 1 or more and TC (012) of 1.3 or less, and I (03)
0) / I (104) and I (012) / I (030) are P
No correlation with R (110), 0.059-7.5 respectively
It can be seen that the values vary from 80, 0.082 to 63.060 and are not consistent. From Table 2, the average particle size of the product of the present invention is 2 μm or less when the thickness of the oxide film is less than 2.5 μm, and 4 μm or less when the thickness is 2.5 μm or more. The average surface roughness Ra is 0.6 μm or less, and the maximum surface roughness Rmax is such that the thickness of the oxide film is 2.5 μm.
Is less than 2 μm and the film thickness is 2.5 μm
In the above case, it is understood that it is 3 μm or less.

An oxide film (corresponding to 1 in FIG. 4), a binding layer (corresponding to 2 in FIG. 4) and a non-oxide film (corresponding to 2 in FIG. 4) mainly containing α-type aluminum oxide in Table 1 of the product of the present invention. (Corresponding to 3 out of 4.) The fracture surface in the vicinity was measured using a field emission scanning electron microscope (FE).
-SEM) are shown in FIGS. 10 and 11. FIG. 10 is an image of the vicinity of the binding layer at a magnification of 20,000, and FIG. From the FE-SEM photographs of the fracture surface of the product of the present invention including FIGS. 10 and 11, the product of the present invention has a thickness between the oxide film mainly composed of α-type aluminum oxide and the non-oxide film as the base. Is 100-500 nm and the particle size is 20-1.
It can be seen that a 60 nm bonding layer is formed. FIG.
2 is a transmission electron microscope (TE) near the bonding layer of the product of the present invention.
M) It is a photograph. In the figure, a bonding layer (FIG. 1) is formed on TiCN crystal grains (B4 and B5 in FIG.
2, B6 and B7 are partially formed), and an oxide film mainly composed of α-type aluminum oxide is formed thereon. FIG. 3 shows a lattice image photograph of the portion a in FIG. 12, that is, the vicinity of the interface between the oxide film mainly composed of α-type aluminum oxide and the bonding layer. The main oxide film, the interface of the oxide film / bonding layer mainly containing α-type aluminum oxide, and the bonding layer are shown. From FIG. 3, α
It can be seen that lattice fringes are continuous at the interface between the oxide film mainly composed of aluminum oxide and the bonding layer. In FIG. 3, the interface between the oxide film and the bonding layer mainly composed of α-type aluminum oxide is not perpendicular but obliquely shown on the TEM photograph surface. The interface between the bonding layer and the underlying non-oxide film (near b in FIG. 12) in FIG.
As a result of the same observation in (EM), it was confirmed that the bonding layer and the non-oxide film were in an epitaxial relationship with each other, and the lattice was continuously grown. FIG. 13 is an observation of the vicinity of the interface between the bonding layer and the oxide film mainly composed of α-type aluminum oxide for the sample 22 in Table 2 of the product of the present invention. FIG.
The upper direction of the oxide film 3 is the upper surface direction of the oxide film. The lattice plane of the coupling layer is seen in the center of FIG. 13, and the lattice plane of the oxide film mainly composed of α-type aluminum oxide is seen on both sides. The lattice fringes are continuous at both interfaces between the bonding layer and the particles of the oxide film mainly composed of α-type aluminum oxide on the right side of the figure and the interface between the bonding layer and the particles of oxide film mainly composed of α-type aluminum oxide on the left side of the figure. You can see that. The interface on the left side of FIG. 13 is an oxide film / bonding layer interface mainly composed of α-type aluminum oxide, which is relatively perpendicular to the TEM photograph surface.

Next, using a cutting tool of the present invention manufactured under the conditions of Examples 1 and 2, each of the five cutting tools of the present invention was used to continuously cut the cast workpiece for one hour under the following conditions. The state of peeling was observed and evaluated using an optical microscope with a magnification of 200 times. Work material FC25 (HB230) Cutting speed 300m / min Feed 0.3mm / rev Depth of cut 2.0mm Using water-soluble cutting oil As a result of this cutting test, all of the above-mentioned present invention products peel off the alumina film even after continuous cutting for 1 hour. No cutting was observed, and the cutting tool was excellent, and when PR (110) was 1.5 or more, the alumina film was not peeled even after continuous cutting for 1.5 hours. . In addition, each of the five cutting tools of the present invention was intermittently cut under the following conditions, and
After the zero-time impact cutting, the chipping state of the blade tip was observed and evaluated by a stereoscopic microscope with a magnification of 50 times. Work material SCM material Cutting conditions 100 m / min Feed 0.3 mm / rev Depth of cut 2.0 mm After the cutting test, any of the above-mentioned products of the present invention can be used without causing any defect in the cutting edge and have a long service life. Was. Also, P
R (110) is 2 or more, and the center line average surface roughness Ra is 0.5.
When the thickness is 5 μm or less, it can be used even after 1,500 times of impact cutting without causing any chipping defect on the cutting edge, and it is found that the cutting edge is more excellent.

(Conventional Example 1) In order to clarify the influence on the various characteristics and the cutting characteristics of the oxide film mainly composed of α-type aluminum oxide due to the difference in the method of forming the bonding layer, WC 72% was used similarly to the product of the present invention. , TiC8%, (Ta, Nb) C11
%, Co 9% (% indicates weight%) on the surface of a carbide substrate for a cutting tool having a thickness of 0.3 μm.
After forming the iN film and 6μm thick TiCN film, after forming a TiC film of H ₂ carrier gas and TiCl ₄ gas and CH ₄ gas are reacted for 5 to 30 minutes at 1010 ° C. using a raw material gas, TiCl ₄ The gas and CH ₄ gas were stopped, and a H ₂ carrier gas and a CO ₂ gas were allowed to flow on the produced TiC film to oxidize the TiC film at 1010 ° C. for 15 minutes to form a bonding layer. Then, 10 times under the same conditions as in Example 1.
A conventional product in which an aluminum oxide film having a predetermined thickness was formed at 20 ° C. using H ₂ gas, AlCl ₃ gas, and CO ₂ gas.

In the above conventional example 1, after forming the bonding layer, H ₂ gas, AlCl ₃ gas and CO ₂
X-ray diffraction of a conventional product in which an aluminum oxide film was produced with a gas yielded the X-ray diffraction pattern shown in FIG. In the case of FIG. 14, the X-ray diffraction peak intensities of α-Al ₂ O ₃ are (116), (104), (012), and (11).
It can be seen that the peak is stronger in the order of 3) and the (110) peak is weaker. In this manufactured conventional example, PR (110), TC (012), and I (03) were measured in the same manner as in the above example.
0) / I (104), I (012) / I (030), average grain size of crystal, center line average surface roughness Ra, maximum surface roughness Rma
x is summarized in Table 3.

[0037]

[Table 3]

From Table 3, it can be seen that the conventional example has a PR (11
0) is less than 1 and I (030) / I (104) and I
(012) / I (030) means 0.122 to 1.302.
And 0.268 to 3.044, which is around 1, and the average particle size is 2 μm even when the thickness of the oxide film is less than 2.5 μm.
And when the film thickness is 2.5 μm or more, 4
It can be seen that it may exceed μm. The center line average surface roughness Ra is 0.6 μm in a region where the film thickness is 2.5 μm or more.
m, and the maximum surface roughness Rmax exceeds 2 μm even when the thickness of the oxide film is less than 2.5 μm, and the maximum thickness is 2.5 μm.
It can be seen that if m is more than m, it may exceed 3 μm.

(Conventional Example 2) Also, after forming a bonding layer in the same manner as in Conventional Example 1, AlCl ₃ gas, H ₂
An aluminum oxide film having a predetermined thickness is formed with a gas, a CO ₂ gas, and a H ₂ S gas. Thereafter, ₄ l / min of H ₂ gas, 50 ml / min of TiCl ₄ gas, and 1.3 l / min of N ₂ gas are formed. FIG. 15 shows a typical X-ray diffraction result of a conventional product in which a titanium nitride film is formed at a flow rate of 1010 ° C. Α-Al in FIG.
_In the case of ₂ O ₃ , the peak intensity of X-ray diffraction is (012), (0
24), (116), and (030) in this order.
0) It can be seen that the peak is weak. PR (110), which was measured under the same conditions as the above example,
TC (012), I (030) / I (104), I (0
12) / I (030), the average grain size of the crystal, the center line average surface roughness Ra, and the maximum surface roughness Rmax are summarized in Table 4.

[0040]

[Table 4]

According to Table 4, H ₂ gas, AlCl ₃ gas, CO
Conventional Example 2 in which an aluminum oxide film was formed at 1010 ° C. using ₂ gas and H ₂ S gas was PR
(110) is less than 1 and I (030) / I (10
4), I (012) / I (030) are each 0.28
9 to 1.547 and 3.184 to 7.836.

As a result of performing the same continuous cutting test as that of the above-mentioned embodiment using five cutting tools of the above-mentioned conventional example, the alumina film was peeled off after 10 minutes of continuous cutting. In addition, each of the five cutting tools of the conventional example was intermittently cut under the same conditions as in the above example, and after 1,000 times of impact cutting, the chipping state of the tip of the cutting edge was observed with a stereoscopic microscope with a magnification of 50 times. Also showed large chipping, which proved to be inferior as a cutting tool.

From the above, it can be seen that even if the method of forming the aluminum oxide film itself is the same, various characteristics of the aluminum oxide film formed thereon can be controlled by changing the method of forming the bonding layer. The bonding layer is made of TiC /
Not limited to TiCO, TiN / TiNO, Ti
The same operation and effect as those of the above embodiment were obtained with any of CN / TiCNO or a plurality of layers in which these were combined.
The underlying film is not limited to TiCN, but may be a non-oxide film (2-2 in FIG. 4, for example, TiC / TiCO) in the bonding layer.
Even with the same material (TiC) as in the bonding layer (TiC), the same operation and effect as in the above-described embodiment were obtained.

[0044]

As described above, according to the product of the present invention, carbides, nitrides, carbonitrides, oxides, oxycarbides, oxynitrides of metals belonging to groups IVa, Va and VIa of the periodic table are formed on the surface of the substrate. Α-type aluminum oxide having a strong (110) plane peak intensity of X-ray diffraction, that is, a strong (110) plane orientation, on a single-layer film of at least one of oxycarbonitride and oxycarbonitride. By forming an oxide film mainly composed of aluminum oxide, the adhesion of the film is good, and a long-life aluminum oxide-coated tool having excellent mechanical properties can be realized.

[Brief description of the drawings]

FIG. 1 shows the X of the aluminum oxide coated tool according to the present invention.
It is a figure which shows a line diffraction pattern.

FIG. 2 shows the X of the tool coated with aluminum oxide according to the present invention.
It is a figure which shows a line diffraction pattern.

FIG. 3 is a photograph showing a crystal structure of an aluminum oxide-coated tool according to the present invention.

FIG. 4 is a schematic diagram for explaining a film configuration of an aluminum oxide-coated tool.

FIG. 5 is a schematic diagram for explaining a lattice image of a film interface of the aluminum oxide-coated tool according to the present invention.

FIGS. 6A and 6B are an SEM photograph (a) relating to a method for measuring the crystal grain size on the surface of aluminum oxide, and a schematic diagram (b) showing the method for measuring the grain size.

FIG. 7 shows the X of the aluminum oxide coated tool according to the present invention.
It is a figure which shows a line diffraction pattern.

FIG. 8 shows the X of the aluminum oxide-coated tool according to the present invention.
It is a figure which shows a line diffraction pattern.

FIG. 9 shows X of the tool coated with aluminum oxide according to the present invention.
It is a figure which shows a line diffraction pattern.

FIG. 10 is a structural photograph of the ceramic material of the aluminum oxide-coated tool according to the present invention.

FIG. 11 is a structural photograph of a ceramic material of an aluminum oxide-coated tool according to the present invention.

FIG. 12 is a structural photograph of a ceramic material of the aluminum oxide-coated tool according to the present invention.

FIG. 13 is a photograph showing a crystal structure of an aluminum oxide-coated tool according to the present invention.

FIG. 14 is a diagram showing an X-ray diffraction pattern of a tool coated with aluminum oxide according to a conventional material.

FIG. 15 is a view showing an X-ray diffraction pattern of a tool coated with aluminum oxide according to a conventional material.

[Brief description of reference numerals]

 1 oxide film, 2 bonding layer, 3 non-oxide film (underlying film).

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Ueda 13 Hitachi Tools Co., Ltd., 13-13 Shinsen, Narita City, Chiba Prefecture (72) Inventor Norihiko Shima Nobuhiko Shima 13 Hitachi Tools Co., Ltd., 13 Shinsen, Narita City, Chiba Prefecture Narita Plant

Claims (9)

[Claims] 1. The method according to claim 1, wherein the surface of the substrate is made of IVa, Va, VIa of the periodic table.
A single-layer coating or a multilayer coating composed of two or more of any one of a group III metal carbide, nitride, carbonitride, oxide, oxycarbide, oxynitride and oxycarbonitride, and at least one α-type oxidation An aluminum oxide-coated tool on which an oxide film mainly composed of aluminum is formed, wherein the strongest X-ray diffraction peak surface of the oxide film is a (110) plane. 2. The substrate of the periodic table, IVa, Va, VIa,
Group 1 metal carbide, nitride, carbonitride, oxide, oxycarbide, oxynitride and oxycarbonitride any one single-layer coating or multilayer coating comprising two or more thereof, and at least one α-type coating In an aluminum oxide-coated tool on which an oxide film mainly composed of aluminum oxide is formed, the equivalent peak intensity PR by the (110) plane of the X-ray diffraction of the oxide film.
(110) is 1 or more, The aluminum oxide coating tool characterized by the above-mentioned. 3. The method according to claim 1, wherein when the thickness of the oxide film mainly composed of α-type aluminum oxide is less than 2.5 μm, the average particle size of the oxide film is 2 μm or less, and when the thickness is 2.5 μm or more. The aluminum oxide-coated tool according to claim 1 or 2, wherein the average particle size is 4 µm or less. 4. The oxidation according to claim 1, wherein the oxide film mainly composed of α-type aluminum oxide has a center line average surface roughness Ra of 0.6 μm or less. Aluminum coated tool. 5. When the thickness of the oxide film mainly composed of α-type aluminum oxide is less than 2.5 μm, the maximum surface roughness Rmax of the oxide film is 2 μm or less, and the thickness is 2.5 μm or less.
The aluminum oxide-coated tool according to any one of claims 1 to 4, wherein the maximum surface roughness Rmax at 3 m or more is 3 m or less. 6. The lattice fringes of the oxide film mainly composed of the α-type aluminum oxide and the lattice fringes of the coupling layer are continuous at the interface so that the adhesion between the films is enhanced. An aluminum oxide-coated tool according to any one of claims 1 to 5. 7. The aluminum oxide coating according to claim 1, wherein a titanium nitride film is formed on a surface of the oxide film mainly composed of the α-type aluminum oxide. tool. 8. A material selected from the group consisting of carbides, nitrides and carbonitrides of metals of groups IVa, Va and VIa of the periodic table and Fe, Ni, C
The aluminum oxide-coated tool according to any one of claims 1 to 7, wherein the base is a super-hard alloy comprising at least one of o, W, Mo, and Cr. 9. A non-oxide film layer made of one or more of carbides, nitrides, and carbonitrides of metals belonging to groups IVa, Va and VIa of the periodic table, and The gas composition used is mainly 0.1 to 5 vol% oxidizing gas, and oxides, oxycarbides, and oxynitrides of metals of Group IVa, Va, and VIa of the periodic table formed at a film formation temperature of 950 to 1020 ° C. A bonding layer consisting of a combination of a thin layer consisting of one or more of a material and an oxycarbonitride,
A method for manufacturing an aluminum oxide-coated tool, comprising forming an oxide film mainly composed of α-type aluminum oxide thereon.