JP5229826B2 - Coating, cutting tool, and manufacturing method of coating - Google Patents

Description

  The present invention relates to a coating, a cutting tool, and a method for manufacturing the coating, and more particularly, to a coating excellent in wear resistance and welding resistance in a high temperature environment, a cutting tool including the coating, and a method for manufacturing the coating.

Conventionally, various coatings are formed on various base materials for the purpose of improving wear resistance and slidability. For example, as a coating used for a cutting tool or the like, for example, a coating made of Al ₂ O ₃ as disclosed in Patent Documents 1 to 5 (hereinafter referred to as “α-Al ₂ O ₃ coating”). There is.

Al ₂ O ₃ is a coating material excellent in wear resistance and heat resistance, but when a CVD method is used to form an α-Al ₂ O ₃ coating, a high substrate temperature of 1000 ° C. or higher is required. When the unbalanced magnetron sputtering method which is a PVD method is used, a high substrate temperature of 750 ° C. or higher is required.

However, after the formation of the α-Al ₂ O ₃ film, the base material on which the α-Al ₂ O ₃ film is formed changes due to the high substrate temperature during the formation of the α-Al ₂ O ₃ film. There has been a problem that the characteristics such as toughness of the cutting tool deteriorate.

Further, a film made of γ-Al ₂ O ₃ (hereinafter referred to as “γ-Al ₂ O ₃ film”) and a film made of amorphous Al ₂ O ₃ (hereinafter referred to as “amorphous Al ₂ O ₃ film”). Can be formed at a low temperature of less than 750 ° C., the film structure is smooth and fine-grained, and is superior to the α-Al ₂ O ₃ coating in welding resistance.

However, the γ-Al ₂ O ₃ coating and the amorphous Al ₂ O ₃ coating have a lower hardness than the α-Al ₂ O ₃ coating, and thus are inferior in wear resistance. The volume change accompanying the transformation to α-Al ₂ O ₃ and other crystal systems results in a sparse and brittle structure, and the wear resistance rapidly deteriorates. As a result, it cannot be used in a high temperature environment.

  In recent cutting tools, high-speed and high-efficiency machining is required, and there are also high demands for dry machining due to environmental considerations. These demands tend to shift the cutting edge temperature of cutting tools to higher temperatures. It is in. Therefore, as a coating for a cutting tool, it is desired to develop a coating having wear resistance and welding resistance in a high temperature environment.

JP 2000-246507 A JP 2001-219303 A JP 2001-219304 A JP 2001-219305 A JP 2001-219306 A

  In view of the above circumstances, an object of the present invention is to provide a coating having excellent wear resistance and welding resistance in a high temperature environment, a cutting tool including the coating, and a method for producing the coating.

The present invention is a film comprising at least one oxide layer, and the composition of the oxide layer is represented by the following formula (1):
(Al _1-x Zr _x ) ₂ O _{3 (1 + y)} (1)
In the formula (1), x is a real number satisfying 0.01 ≦ x ≦ 0.07, y is a real number satisfying −0.1 ≦ y ≦ 0.2, and the oxide layer is a γ-alumina type have a crystal structure and an amorphous structure, in the formula (1), x is a real number der Ru film satisfying 0.025 ≦ x ≦ 0.04.

  Moreover, in the film of this invention, it is preferable that the layer thickness of an oxide layer is 0.05 micrometer or more and 20 micrometers or less.

  Moreover, in the film of this invention, it is preferable that an oxide layer has a compressive residual stress of 0.1 GPa or more and 10 GPa or less.

  In the coating of the present invention, the content ratio of the γ-alumina type crystal structure and the amorphous structure in the oxide layer (γ-alumina type crystal structure / (γ-alumina type crystal structure + amorphous) The structure)) is preferably 10% or more and 90% or less.

  Further, in the coating of the present invention, at least one metal nitride selected from the group consisting of Ti (titanium), Al (aluminum), Cr (chromium), Zr (zirconium), and Si (silicon), charcoal It is preferable to include at least one compound layer made of nitride, nitride oxide, carbonate or oxynitride.

  Moreover, in the film of this invention, it is preferable that the film thickness of a film is 0.05 micrometer or more and 25 micrometers or less.

  Moreover, this invention is a cutting tool containing a base material and one of said coating films formed on the base material.

  Here, in the cutting tool of the present invention, the base material may be high-speed steel, cemented carbide, cermet, ceramic sintered body, diamond sintered body, or cubic boron nitride sintered body.

  Furthermore, this invention is a manufacturing method of a film including the process of forming at least one said oxide layer by PVD method.

  Here, in the method for producing a film of the present invention, at least one metal nitride, carbonitride, nitride oxide selected from the group consisting of Ti, Al, Cr, Zr and Si by PVD method, It is preferable to include a step of forming at least one compound layer made of carbonate or carbonitride.

  In the method for producing a coating film of the present invention, the PVD method may be at least one selected from the group consisting of an arc ion plating method, an unbalanced magnetron sputtering method, and a dual magnetron sputtering method.

In the method for producing a coating film of the present invention, the oxide layer can be formed by a dual magnetron sputtering method, and the compound layer can be formed by an arc ion plating method.

  In the method for producing a coating film of the present invention, an Al target and a Zr target can be attached to a pair of magnetron electrodes used in the dual magnetron sputtering method, respectively.

  In the method for producing a coating film of the present invention, the oxide layer can be formed by an unbalanced magnetron sputtering method, and the compound layer can be formed by an arc ion plating method.

  ADVANTAGE OF THE INVENTION According to this invention, the coating tool excellent in abrasion resistance and welding resistance in a high temperature environment, the cutting tool containing the coating film, and the manufacturing method of the coating film can be provided.

It is a figure which shows the outline of an example of the apparatus which forms the film of this invention. It is a typical expanded side view illustrating the cutting of the work material by the cutting tool of the present invention.

  Embodiments of the present invention will be described below. In the drawings of the present invention, the same reference numerals represent the same or corresponding parts.

(Coating)
The film of the present invention includes at least one oxide layer described later. When the coating film of the present invention is a single layer, the coating film of the present invention is constituted only by an oxide layer described later. However, when the coating film of the present invention is a plurality of layers, an oxide layer described later is provided. A plurality of layers may be included, and a layer other than an oxide layer such as a compound layer described later may be included in addition to the oxide layer described later.

  Moreover, the formation position of the oxide layer described later when the coating film of the present invention is a plurality of layers is not particularly limited. Therefore, the oxide layer described later may be formed at a position in contact with the substrate in the coating of the present invention, or may be formed at the position of the outermost surface. It may be formed at an intermediate position that is neither of the above.

  Further, the film thickness of the coating of the present invention is preferably 0.05 μm or more and 25 μm or less, and more preferably 0.5 μm or more and 10 μm or less. When the thickness of the coating of the present invention is less than 0.05 μm, the wear resistance of the coating may not be sufficient, and the effect of extending the life of the cutting tool may not be exhibited. May change and the wear resistance of the coating may not be exhibited. Moreover, when the film thickness of the film of the present invention is 0.5 μm or more and 10 μm or less, the film tends to have sufficient wear resistance.

(Oxide layer)
The film of the present invention includes one or more oxide layers, and the composition of the oxide layer is represented by the following formula (1):
(Al _1-x Zr _x ) ₂ O _{3 (1 + y)} (1)
In the above formula (1), x is a real number that satisfies 0.01 ≦ x ≦ 0.07, y is a real number that satisfies −0.1 ≦ y ≦ 0.2, and the oxide layer is γ− It is characterized by having an alumina type crystal structure and an amorphous structure.

Here, in the present invention, “the oxide layer has a γ-alumina type crystal structure and an amorphous structure” means that the oxide layer has a mixture of a γ-alumina type crystal structure and an amorphous structure. In the γ-alumina (γ-Al ₂ O ₃ ) type crystal structure in the oxide layer, it is included in the oxide layer at the position where Al atoms of the γ-Al ₂ O ₃ crystal are present. This means that it has a crystal structure in which O atoms contained in the oxide layer are present at positions where the metal atoms are present and O atoms of the γ-Al ₂ O ₃ crystal are present.

  Further, the content ratio of the γ-alumina type crystal structure to the amorphous structure in the oxide layer (γ-alumina type crystal structure / (γ-alumina type crystal structure + amorphous structure)) is 10% or more. It is preferably 90% or less, and more preferably 50% or more and 85% or less. The content ratio of γ-alumina type crystal structure and amorphous structure in the oxide layer (γ-alumina type crystal structure / (γ-alumina type crystal structure + amorphous structure)) is 10% or more and 90% Hereinafter, particularly in the case of 50% or more and 85% or less, the balance between the hardness and smoothness of the oxide layer becomes good, and as a result, both the wear resistance and the welding resistance have good characteristics. There is a tendency to obtain cutting tools.

  Here, in the present invention, the content ratio of the γ-alumina crystal structure and the amorphous structure in the oxide layer (γ-alumina crystal structure / (γ-alumina crystal structure + amorphous structure) ) Is a ratio of the area occupied by the crystal of the γ-alumina type crystal structure to the area of the surface of the oxide layer observed by SEM (scanning electron microscope) Is divided by the sum of the ratio of the area occupied by the crystal of the γ-alumina type crystal structure and the ratio of the area occupied by the amorphous structure. The area occupied by the crystals of the γ-alumina type crystal structure is the total area when there are a plurality of crystals of the γ-alumina type crystal structure, and is occupied by the amorphous structure. When there are a plurality of amorphous structures, the total area is the total area.

Further, the ratio x of the number of Zr atoms when the total number of atoms in the oxide layer (the total number of Al atoms and Zr atoms) is 1 is set to 0.01 or more and 0.07 or less. The layer structure can be a structure having a γ-alumina type crystal structure and an amorphous structure, and the wear resistance of the film using this oxide layer at high temperatures is improved. In the above formula (1), when x is less than 0.01, it is difficult to improve the hardness of the oxide layer by adding Zr, and when x exceeds 0.07, the hardness of the oxide layer May significantly decrease and the ZrO ₂ phase may be precipitated.

  Furthermore, the hardness of an oxide layer can be made high by making y of said Formula (1) into -0.1 or more and 0.2 or less. In the above formula (1), y is more preferably −0.05 or more and 0.1 or less. In the above formula (1), 3 (1 + y) at the lower right of O is an O atom when the total number of atoms in the oxide layer (the total number of Al atoms and Zr atoms) is 2. It represents the ratio of numbers. In view of technical common sense, the possibility that the value of y exceeds 0.2 is considered to be very low.

  In the above formula (1), x is more preferably 0.025 or more and 0.04 or less. In this case, since the hardness and heat resistance of the oxide layer are further improved, the wear resistance and heat resistance of the coating containing the oxide layer tend to be further improved.

The layer thickness of the oxide layer is preferably 0.05 μm or more and 20 μm or less, 0.5
More preferably, it is not less than μm and not more than 5 μm. When the thickness of the oxide layer is less than 0.05 μm, the effect of improving the wear resistance, heat resistance and chemical stability due to the formation of the oxide layer is not sufficient, and the life of the cutting tool is extended. It is difficult to obtain an effect. Further, when the thickness of the oxide layer exceeds 20 μm, the oxide layer tends to be easily peeled off. When the thickness of the oxide layer is 0.05 μm or more and 20 μm or less, particularly when the thickness is 0.5 μm or more and 5 μm or less, the coating film has stable wear resistance even under a severe environment such as a high temperature environment, It tends to exhibit heat resistance and chemical stability.

  The oxide layer preferably has a compressive residual stress of 0.1 GPa or more and 10 GPa or less, and more preferably has a compressive residual stress of 0.5 GPa or more and 5 GPa or less. When the compressive residual stress of the oxide layer is 0.1 GPa or more and 10 GPa or less, particularly 0.5 GPa or more and 5 GPa or less, the impact resistance of the coating tends to be increased, and the toughness of the substrate on which the coating is formed tends to be increased. It is in. In addition, when the compressive residual stress of the oxide layer is less than 0.1 GPa, the effect of the oxide layer having the compressive residual stress is not recognized, and when the compressive residual stress is greater than 10 GPa, the oxide layer compresses itself. It becomes easy to peel off due to residual stress.

  The compressive residual stress of the oxide layer can be applied, for example, by applying a bias voltage to the substrate when forming the oxide layer on the substrate. By appropriately adjusting the bias voltage, the magnitude of the compressive residual stress of the oxide layer can be appropriately adjusted. The bias voltage applied to the substrate may be a DC voltage, but may be a bias voltage in which positive and negative are switched at a frequency of 20 kHz or higher, preferably 40 kHz or higher.

The compressive residual stress of the oxide layer is calculated by forming an oxide layer on the surface of a thin plate-like substrate and measuring the radius of curvature of the substrate warpage caused by the compressive residual stress of the oxide layer. Can do. Specifically, the compressive residual stress of the oxide layer is that of "Thin Film Mechanical Properties Evaluation Technology-Tribology / Internal Stress / Adhesion" (issued March 19, 1992, publisher: Realize Inc.). 228 pp is the (9) formula ^{_{S = E s D 2/6}} (1-ν s) R, can be calculated by determining the S by substituting the radius of curvature R of the measured said substrate. Incidentally, in this equation, E _s denotes the Young's modulus of the substrate, D is shown the thickness of the substrate, [nu _s represents the Poisson's ratio of the substrate.

(Compound layer)
The coating of the present invention may contain at least one layer other than the above oxide layer. The layer other than the oxide layer includes at least one metal nitride, carbonitride, nitride oxide, carbonate or carbonitride oxidation selected from the group consisting of Ti, Al, Cr, Zr and Si. A compound layer made of a material (hereinafter referred to as “compound layer”) may be included.

  Here, carbonitride is a compound containing carbon and nitrogen, nitrogen oxide is a compound containing nitrogen and oxygen, and carbon oxide is a compound containing carbon and oxygen. The carbonitride oxide is a compound containing carbon, nitrogen, and oxygen.

  Since the compound layer is high in hardness and excellent in heat resistance and chemical stability, a film having excellent wear resistance, heat resistance and chemical stability can be obtained by combining with the above oxide layer. You may be able to get it.

As the compound layer, for example, a TiAlN layer, TiSiN layer, AlCrN layer, TiAlSiN layer, TiAlNO layer, AlCrSiCN layer, TiCN layer, TiSiC layer, CrSiN layer, AlTiSiCO layer, or TiSiCN layer can be used. In the present specification, for example, when the ratio of the number of atoms of the elements described on the left side of the “layer” is not described at all, such as “TiAlN layer”, the number of atoms is not specified unless otherwise specified. It means that there is no limit to the ratio. That is, in this specification, for example, “TiAlN layer” is not limited to a layer in which the atomic ratio is Ti: Al: N = 0.5: 0.5: 1, and Ti _z This means any conventionally known layer represented by the formula Al _1-z N (where 0 <z <1), and the same applies to the description of layers other than the “TiAlN layer”. In the compound layer according to the present invention, a metal element such as Ti, Al, Si, or Cr and a non-metal element such as N (nitrogen), O (oxygen), or C (carbon) are not necessarily in a stoichiometric composition. It is not necessary to configure.

  Here, since the TiAlN layer has a very high hardness, when the TiAlN layer is included in the coating of the present invention, it tends to be excellent in wear resistance.

  In addition, since the TiSiN layer has high hardness and excellent heat resistance, and has a very fine structure and suppresses permeation of oxygen, when the TiSiN layer is included in the coating of the present invention, The abrasion resistance and heat resistance of the coating are excellent, and oxidation of the substrate on which the coating is formed can be suppressed.

  Moreover, since the AlCrN layer has high hardness and does not contain Ti, it has better oxidation resistance than the TiAlN layer and TiSiN layer and has higher heat resistance, so the AlCrN layer is included in the coating of the present invention. In such a case, the wear resistance, heat resistance and chemical stability of the coating tend to be improved. In addition, the AlCrN layer is excellent in adhesion with the oxide layer.

In addition, since the TiAlSiN layer has the characteristics of both the TiAlN layer and the TiSiN layer, and the characteristics are superior to those of the TiAlN layer and the TiSiN layer, the TiAlSiN layer is included in the coating of the present invention. In such a case, the wear resistance, heat resistance and chemical stability of the coating tend to be further improved. Here, TiAlSiN layer is a compound layer of the formula of _{Ti 1-ab Al a Si b} N (0 <a <1,0 <b <1), b showing an atomic ratio of Si, It is preferable to satisfy 0.01 <b <0.3. Here again, the metal element and the non-metal element do not necessarily constitute a stoichiometric composition.

  The layer thickness of the compound layer is preferably 0.05 μm or more and 20 μm or less, and more preferably 0.5 μm or more and 10 μm or less. When the thickness of the compound layer is less than 0.05 μm, the effect of improving the wear resistance, heat resistance and chemical stability due to the formation of the compound layer is not sufficient, and the effect of extending the life of the cutting tool is achieved. Difficult to get. Further, when the thickness of the compound layer exceeds 20 μm, the compound layer tends to be easily peeled off. When the layer thickness of the compound layer is 0.05 μm or more and 20 μm or less, particularly when the thickness is 0.5 μm or more and 10 μm or less, the film has stable wear resistance and heat resistance even under severe conditions such as high temperature environments. Tend to exert sexuality and chemical stability.

  Further, when two or more compound layers are included in the coating of the present invention, each compound layer may be a layer having the same composition, or may be a layer having a different composition from each other, There may be a mixture of at least two layers having the same composition and layers having different compositions.

(Cutting tools)
The cutting tool of the present invention has a structure including a base material and the above-described coating film of the present invention coated on the base material. Examples of the cutting tool of the present invention include drills, end mills, milling or turning cutting tips for turning, metal saws, gear cutting tools, reamers, taps or tips for crankshaft pin milling.

  As the base material included in the cutting tool of the present invention, a conventionally known material known as the base material for the above-described cutting tool can be used without particular limitation, and for example, high speed steel, cemented carbide (for example, WC) Cemented carbide, WC, Co, or further carbonitride such as Ti, Ta, Nb etc.), Cermet (TiC, TiN, TiCN etc.) A sintered body (such as titanium carbide, silicon carbide, boron nitride, aluminum nitride, aluminum oxide), a cubic boron nitride sintered body, a diamond sintered body, or the like can be used.

  When a cemented carbide is used as a base material included in the cutting tool of the present invention, free carbon or an abnormal phase called η phase may be included in the structure of the cemented carbide.

  Further, the base material included in the cutting tool of the present invention may have a modified surface. For example, when a cemented carbide is used as the base material included in the cutting tool of the present invention, a de-β layer may be formed on the surface, and when a cermet is used, a hardened surface layer is formed on the surface. May be.

(Method for producing coating)
The coating of the present invention is formed by, for example, a PVD (Physical Vapor Deposition) method, a thermal CVD (Chemical Vapor Deposition) method, a MOCVD (Metal Organic Chemical Vapor Deposition) method, a PCVD (Plasma Chemical Vapor Deposition) method, or a wet method. Can do. Among these, from the viewpoint of easily forming a dense and compressive residual stress film at a low temperature, it is preferable to use the PVD method as the method for producing the film of the present invention.

  Here, as the PVD method, for example, at least one selected from the group consisting of an arc ion plating method, an unbalanced magnetron sputtering method, and a dual magnetron sputtering method can be used.

(I) Arc type ion plating method As an example of the arc type ion plating method, an example of a method of forming the TiAlN layer as the above compound layer on the substrate by the arc type ion plating method will be described below. .

  First, a base material is installed in the apparatus, and a target (Ti-Al target) made of a Ti—Al alloy is set in the apparatus as an arc evaporation source so as to face the base material. Next, nitrogen is introduced into the apparatus to form a gas atmosphere composed of nitrogen.

  And after applying a voltage to said Ti-Al target, arc discharge is produced from a Ti-Al target. Thereby, the Ti—Al target is melted, and Ti atoms and Al atoms are released from the Ti—Al target. At least a part of Ti atoms and Al atoms emitted from the Ti—Al target collide with electrons in the arc discharge to become ions. Then, Ti atoms and / or Ti ions and Al atoms and / or Al ions reach the substrate, respectively, and form a TiAlN layer together with nitrogen. Thereby, a TiAlN layer is formed on the substrate. Here, in the arc type ion plating method, the atomic ratio of Ti, Al, and N can be appropriately set by appropriately adjusting the composition ratio and formation conditions of the Ti—Al target.

In such an arc type ion plating method, since the ionization rate is high and the deposition rate is high, it is selected from the group consisting of Ti, Al, Cr, Zr and Si, which is high in hardness, dense and excellent in wear resistance. It tends to be possible to form a compound layer composed of nitride, carbonitride, nitride oxide, carbonate or carbonitride of at least one metal produced at low temperature.

  In the above description, the case where the compound layer is formed using the arc type ion plating method has been described. However, in the present invention, the oxide layer, the oxide layer, and the compound layer other than the compound layer are used using the arc type ion plating method. It goes without saying that layers may be formed. In the present invention, the arc ion plating method is not limited to the above-described method, and a conventionally known arc ion plating method can be used.

(Ii) Unbalanced Magnetron Sputtering Method Hereinafter, as an example of the unbalanced magnetron sputtering method, an example of a method for forming the oxide layer on the substrate by the unbalanced magnetron sputtering method will be described.

  First, in the apparatus in which one magnetron electrode provided with a magnet is installed, a base material is set so as to face the magnetron electrode, and a target made of an Al—Zr alloy (Al—Zr target) is placed on the magnetron electrode. ) Is set.

  Next, a gas containing oxygen and a rare gas such as argon, xenon, krypton, or helium is introduced into the apparatus. A pulsed DC voltage is applied to the magnetron electrode to generate the rare gas and oxygen gas plasma. The rare gas ions generated by the generation of this plasma collide with the Al—Zr target, and Al atoms and Zr atoms are released from the Al—Zr target, respectively.

  Here, in the unbalanced magnetron sputtering method, since the magnetic field generated by the magnetron electrode is unbalanced, the plasma is generated compared to the balanced magnetron sputtering method in which the magnetic field generated by the magnetron electrode is balanced. The range can be expanded to the vicinity of the substrate.

  Then, Al atoms and / or Al ions and Zr atoms and / or Zr ions respectively reach the substrate, and form the oxide layer together with oxygen there. Thereby, an oxide layer is formed on the substrate. Here, by appropriately adjusting the composition ratio of the Al—Zr target and the conditions of the unbalanced magnetron sputtering method, it is possible to make Al, Zr and O each have a composition represented by the above formula (1). .

  In such an unbalanced magnetron sputtering method, when a negative bias voltage is applied to the substrate, an oxide layer is formed by using an attractive force acting between the substrate and Al ions and Zr ions. Therefore, the oxide layer can be formed at a low substrate temperature, and a dense oxide layer with high hardness can be formed.

  In the unbalanced magnetron sputtering method, when the oxide layer is formed while alternately changing the polarity of the voltage applied to the target at a frequency of 10 kHz or more and 1 MHz or less, a denser oxide layer is efficiently formed. It is preferable in that it can be formed. The frequency is more preferably 20 kHz or more, further preferably 40 kHz or more, and more preferably 500 kHz or less.

(Iii) Dual Magnetron Sputtering Method Hereinafter, as an example of the dual magnetron sputtering method, an example of a method for forming the oxide layer on the substrate by the dual magnetron sputtering method will be described.

  First, a target made of Al (Al target) is set on one magnetron electrode of a pair of magnetron electrodes installed in the apparatus, and a target made of Zr (Zr target) is set on the other magnetron electrode. Here, the magnetron electrodes are respectively installed so as to face the base material, and these magnetron electrodes are connected to one bipolar power source. Each magnetron electrode is provided with a magnet.

  Next, a gas containing oxygen and a rare gas such as argon, xenon, krypton, or helium is introduced into the apparatus. A pulsed DC voltage is applied between the pair of magnetron electrodes to generate the rare gas and oxygen gas plasma. The rare gas ions generated by the generation of the plasma collide with the target, and Al atoms and Zr atoms are emitted from the target, respectively. Here, since the anode and the cathode are alternately switched in the pair of magnetron electrodes, the collision of the rare gas ions with the Al target and the collision with the Zr target are alternately performed.

  And at least a part of each of Al atoms and Zr atoms released from the target by collision of rare gas ions reaches the substrate as ions, and forms an oxide layer together with oxygen there. Thereby, an oxide layer is formed on the substrate. Here, by appropriately adjusting the conditions of the dual magnetron sputtering method, it is possible to make Al, Zr and O each have a composition represented by the above formula (1).

  Note that in the dual magnetron sputtering method, the voltage and / or power of the Al target and the voltage and / or power of the Zr target can be controlled to some extent independently, and sputtering is performed under optimum conditions for the Al target and the Zr target. Therefore, an oxide layer in which Al and Zr are uniformly dispersed can be formed.

  In the dual magnetron sputtering method, strong discharge occurs between the magnetron electrode on which the Al target is set and the magnetron electrode on which the Zr target is set. Therefore, the oxidation is smooth and smooth at a low substrate temperature. A physical layer can be formed.

  Here, in the magnetron electrode on which the Al target is set and the magnetron electrode on which the Zr target is set, the frequency for alternately switching between the anode and the cathode is preferably 20 kHz or more, and more preferably 40 kHz or more. The frequency is preferably 1 MHz or less, and more preferably 500 kHz or less.

  When the frequency is less than 20 kHz, abnormal discharge may occur due to the oxide layer formed on the surface of the target, and the oxide layer may not be stably formed on the substrate. In addition, when the above frequency is 40 kHz or more, there is a tendency to suppress even a small abnormal discharge caused by dirt or scratches on the surface of the target, and it is possible to efficiently form a higher quality oxide layer. It tends to be possible.

  Further, when the above frequency is higher than 1 MHz, the cost of the apparatus tends to increase from the viewpoint that high frequency countermeasures are required. From the viewpoint of suppressing an increase in cost of the apparatus, the frequency is preferably 500 kHz or less.

Further, in the dual magnetron sputtering method, plasma generated between a pair of magnetron electrodes can reach a range near the substrate. Thereby, since the plasma density in the vicinity of the substrate can be improved, a more efficient oxide layer can be formed.

  In the unbalanced magnetron sputtering method and the dual magnetron sputtering method, when the oxide layer is formed while alternately changing the polarity of the pulsed DC voltage applied to the substrate at a frequency of 10 kHz to 1 MHz, This is preferable in that a denser oxide layer can be efficiently formed at a lower substrate temperature.

  In the above description, the unbalanced magnetron sputtering method and the dual magnetron sputtering method have been described with respect to the case where an oxide layer is formed. In the present invention, the above-described compound is formed by the unbalanced magnetron sputtering method or the dual magnetron sputtering method. It goes without saying that layers other than the layer and the compound layer and the oxide layer may be formed. In the present invention, the unbalanced magnetron sputtering method and the dual magnetron sputtering method are not limited to the above-described methods, and conventionally known unbalanced magnetron sputtering methods and dual magnetron sputtering methods can be used.

  Moreover, in the above, each example in the case of using the arc type ion plating method, the unbalanced magnetron sputtering method or the dual magnetron sputtering method has been described, but in the formation of the film of the present invention, a method other than the above is used. Needless to say.

  In the method for producing a coating film of the present invention, for example, when two or more oxide layers are included, the method for forming each oxide layer may or may not be the same. . Further, in the method for producing a coating film of the present invention, for example, when two or more compound layers are included, the method for forming each compound layer may or may not be the same.

(Sample No. 1-8)
A cemented carbide cutting tip having a composition of JIS standard P30 and a shape of JIS standard SNG432 is used as a base material, and an arc ion plating method using the apparatus schematically shown in FIG. And Sample No. in Table 1 by the dual magnetron sputtering method. A coating tool having a structure described in each of columns 1 to 8 was formed to produce a cutting tool. Hereinafter, sample No. A method for forming the coating film of the cutting tools 1 to 8 will be specifically described.

  First, in the apparatus 1 shown in FIG. 1, two arc evaporation sources, a first arc evaporation source 13 and a second arc evaporation source 14, are set, and a first dual magnetron sputtering source 11 and a second dual magnetron are set. Two dual magnetron sputtering sources, called a sputtering source 12, are set. Then, the base material 10 is placed on the rotating holder 8 that rotates around the center points of the first arc evaporation source 13, the second arc evaporation source 14, the first dual magnetron sputtering source 11, and the second dual magnetron sputtering source 12. I set it. The device 1 also includes a heater 16.

Here, a Ti target was set as the first arc evaporation source 13, and a Ti (80 atomic%)-Si (20 atomic%) target was set as the second arc evaporation source 14. As the first dual magnetron sputtering source 11, an Al target was set on one of a pair of magnetron electrodes, and a Zr target was set on the other. Further, as the second dual magnetron sputtering source 12, an Al target was set on one of a pair of magnetron electrodes, and a Zr target was set on the other.

Then, after the vacuum in the apparatus 1 is evacuated to 7 × 10 ⁻⁴ Pa or less, argon is introduced from the gas inlet 15 and the base material 10 is heated to 650 ° C. while maintaining the vacuum at 3 Pa. Held for hours.

  Then, the surface of the base material 10 was cleaned by argon ions by applying a voltage of −1000 V to the base material 10 to generate glow discharge in argon. Then, argon was exhausted from the apparatus 1 after the cleaning process.

Next, after introducing nitrogen into the apparatus 1 from the gas inlet 15, the second arc evaporation source 14 is discharged with a discharge current of 100 A while applying a voltage of −200 V to the base material 10, thereby generating an arc type. A Ti _0.8 Si _0.2 N layer (the first layer of sample Nos. 1 to 8 in Table 1) was formed on the surface of the substrate 10 by ion plating. Then, after the formation of the Ti _0.8 Si _0.2 N layer, the gas in the apparatus 1 was exhausted.

Subsequently, argon and oxygen are introduced into the apparatus 1 from the gas inlet 15 and the degree of vacuum is maintained at 1 Pa, while the pair of magnetron electrodes of the first dual magnetron sputtering source 11 and the second dual magnetron sputtering source 12 are connected. A voltage having a frequency of 50 kHz alternately switching between the anode and the cathode is applied to each of the pair of magnetron electrodes to be discharged, and a pulsed DC voltage that switches from +15 V to −150 V at a frequency of 55 kHz is applied to the substrate 10. When applied, an oxide layer represented by the formula of (Al _1-x Zr _x ) ₂ O _{3 (1 + y)} by the dual magnetron sputtering method (second layer of sample Nos. 1 to 8 in Table 1) Formed. Here, by adjusting the negative voltage value of the pulsed DC voltage applied to the substrate 10, the compressive residual stress generated in the oxide layer was adjusted to the value shown in Table 1. And after formation of said oxide layer, the gas in the apparatus 1 was exhausted.

Next, after introducing methane and nitrogen into the apparatus 1 from the gas inlet 15, the first arc evaporation source 13 is discharged with a discharge current of 100 A, so that the surface of the substrate 10 is formed by the arc ion plating method. A TiC _0.2 N _0.8 layer (a third layer of sample Nos. 1 to 8 in Table 1) was formed.

  Thereby, the sample No. 1 in which the first layer, the second layer, and the third layer shown in Table 1 were formed on the surface of the substrate 10 was obtained. 1 to 8 cutting tools were obtained.

  Sample No. In forming the coating film of the cutting tools 1 to 8, the first layer and the third layer shown in Table 1 are sample Nos. 1 to 8 were formed under the same conditions, but the second layer shown in Table 1 was sample No. No. 1 was formed without setting a Zr target. About 2-8, it formed by changing suitably the formation conditions, especially the electric power applied to each of an Al target and a Zr target. For example, sample No. The oxide layer of the cutting tool 2 was formed under the condition that the power applied to the Al target was 7 kW, the power applied to the Zr target was 1.5 kW, and the substrate temperature was 720 ° C.

In Table 1, “γ” in the column of the crystal structure of the second layer means a γ-alumina type crystal structure, and “γ + amo” means that a γ-alumina type crystal structure and an amorphous structure are “Amo + ZrO ₂ ” means that the ZrO ₂ phase appears together with the amorphous phase.

  The crystal structure of the second layer in Table 1 was identified by using an X-ray diffractometer to obtain an X-ray diffraction pattern by a thin film method with an X-ray incident angle fixed at a predetermined angle.

Also, the column of “γ / (γ + amo)” in Table 1 shows the content ratio of the γ-alumina type crystal structure and the amorphous structure in the second layer (γ-alumina type crystal structure / (γ-alumina type). Crystal structure + amorphous structure)).

  Here, the content ratio of the γ-alumina type crystal structure and the amorphous structure in the second layer (γ-alumina type crystal structure / (γ-alumina type crystal structure + amorphous structure)) No. The first layer and the second layer were respectively produced in this order on the base material in the same manner and under the same conditions as those of 1-21, and the surface of the produced second layer was observed by SEM and observed. The ratio of the area occupied by the crystal of the γ-alumina type crystal structure to the area of the surface of the second layer is the ratio of the area occupied by the crystal of the γ-alumina type crystal structure and the amorphous structure. Calculated by dividing by the sum of the proportion of occupied area. The area occupied by the crystals of the γ-alumina type crystal structure is the total area when there are a plurality of crystals of the γ-alumina type crystal structure, and the area occupied by the amorphous structure described above. When there are a plurality of amorphous structures, the total area is defined as the total area.

  Further, “−” in the stress column in Table 1 means that compressive residual stress is generated in the layer, and the numerical value located to the right of “−” indicates the magnitude of the compressive residual stress of the layer.

  Sample No. 1 in Table 1 The numerical values of “x” and “y” of the second layer of Nos. 1 to 21 are sample No. It is the value calculated | required by measuring using the Rutherford backscattering method (RBS method) about the oxide layer of the single layer formed on the same conditions as each of the 2nd layer of 1-21.

(Sample Nos. 9 to 15)
Sample No. shown in Table 1 For the films 9 to 15, the target set as each evaporation source and the gas (introduction gas) introduced into the apparatus 1 are as follows, and the volume ratio of methane and nitrogen introduced at the time of forming the third layer is changed. Except for the above, sample no. Samples Nos. 2 to 7 were formed in the same manner. 9-15 cutting tools were obtained.

The first dual magnetron sputtering source 11 and the second dual magnetron sputtering source 12 are sample Nos. 2-7, an Al target and a Zr target were set, and sample No. The second layers 9 to 15 were formed by appropriately changing the compressive stress of the second layer by appropriately changing the pulsed DC voltage applied to the substrate 10. First arc evaporation source 13: Ti target Second arc evaporation source 14: Ti (50 atomic%)-Al (50 atomic%) Target introduction gas: nitrogen / oxygen (first layer), oxygen / argon (second layer) , Nitrogen / Methane (3rd layer)
(Sample Nos. 16-21)
Sample No. shown in Table 1 Samples Nos. 16 to 21 except that the target to be set as each evaporation source and the introduced gas were as follows. Sample No. 2 was formed on the substrate in the same manner as in Nos. 2-7. 16-21 cutting tools were obtained.

The first dual magnetron sputtering source 11 and the second dual magnetron sputtering source 12 are sample Nos. 2-7, an Al target and a Zr target were set, and sample No. For the second layers 16 to 21, the content ratio of the γ-alumina type crystal structure and the amorphous structure in the second layer (γ-alumina type crystal structure / ( The γ-alumina type crystal structure + amorphous structure)) was appropriately changed and formed. For example, sample No. The temperature of the base material 10 at the time of forming the second layer 21 was 550 ° C.
First arc evaporation source 13: Ti (95 atom%)-Si (5 atom%) target Second arc evaporation source 14: Al (50 atom%)-Cr (40 atom%)-Si (10 atom%)
Target introduction gas: nitrogen / methane (first layer), oxygen / argon (second layer), methane (third layer)
(Sample No. 22)
Sample No. 1 in which the first layer, the second layer, and the third layer shown in Table 1 were formed on the surface of the substrate 10 using a conventional thermal CVD method. 22 cutting tools were obtained.

(Sample No. 23)
A Ti (50 atomic%)-Al (50 atomic%) target was set as the first arc evaporation source 13 shown in FIG. 1, and a Ti target was set as the second arc evaporation source 14. In addition, nothing was set as the first dual magnetron sputtering source 11 and the second dual magnetron sputtering source 12.

Then, after the vacuum in the apparatus 1 is evacuated to 7 × 10 ⁻⁴ Pa or less, argon is introduced from the gas inlet 15 and the base material 10 is heated to 650 ° C. while maintaining the vacuum at 3 Pa. Held for hours.

  Then, the surface of the base material 10 was cleaned by argon ions by applying a voltage of −1000 V to the base material 10 to generate glow discharge in argon. Then, argon was exhausted from the apparatus 1 after the cleaning process.

  Next, after nitrogen is introduced into the apparatus 1 from the gas inlet 15, the second arc evaporation source 14 is discharged in a state where a voltage of −200 V is applied to the base material 10, whereby an arc ion plating method is used. A TiN layer (first layer of sample No. 23 in Table 1) was formed on the surface of the substrate 10.

Thereafter, the first arc evaporation source 13 is discharged in a state where a voltage of −200 V is applied to the base material 10, whereby a Ti _0.5 Al _0.5 N layer (Table 1) is formed on the surface of the base material 10 by an arc ion plating method. Sample No. 23 of the second layer) was formed. Then, after the Ti _0.5 Al _0.5 N layer was formed, the gas in the apparatus 1 was exhausted.

  Thereby, the sample No. 1 in which the first layer and the second layer shown in Table 1 were formed on the surface of the substrate 10. 23 cutting tools were obtained.

(Evaluation)
Sample No. shown in Table 1 By using the cutting tools 1 to 23 and rotating the work material 3 after bringing the corners of the cutting tool 2 into contact with the work material 3 as shown in the schematic enlarged side view of FIG. The wear width of the flank 4 of the cutting tool 2 was measured by subjecting the work material 3 to continuous cutting (continuous cutting test) and intermittent cutting (intermittent cutting test) under the cutting conditions shown. The results are shown in Table 3. The smaller the value of the flank wear width shown in Table 3, the better the wear resistance of the coating film of the cutting tool.

  As is apparent from Table 3, the sample No. 1 has a composition represented by the above formula (1) and an oxide layer having a γ-alumina type crystal structure and an amorphous structure in the second layer. 2-7 and sample no. The flank wear width in the continuous cutting test of the cutting tools 9 to 20 is the sample No. having no oxide layer in the second layer. It was smaller than the flank wear width of the cutting tools 1, 8, 21, 22, and 23. Therefore, considering that the cutting environment is a high temperature environment, the sample No. 2-7 and sample no. It was confirmed that the wear resistance of the coating of 9 to 20 cutting tools in a high temperature environment is excellent.

  In particular, sample no. The cutting tools 9 and 22 were defective in the intermittent cutting test. In the 23 cutting tools, peeling of the film was observed in the continuous cutting test.

  In addition, after the above continuous cutting test, the sample No. 2-7 and sample no. When the welding resistance of the cutting tools 9 to 20 was also evaluated, Sample No. 2-7 and sample no. Since it was confirmed that the work material did not adhere to the outermost surface of the cutting tools 9 to 20, the sample No. 2-7 and sample no. It was confirmed that the coatings of 9 to 20 cutting tools were excellent in welding resistance in a high temperature environment.

(Sample No. 24)
Sample No. 2 types shown in Table 5 in which the shape of the base material is SNGN120408 (JIS-B-4121) and the base material is cermet and cubic boron nitride sintered body instead of the base material used in 1 to 23 A base material was prepared.

Then, on each base material made of cermet and cubic boron nitride sintered body, sample Nos. In Table 4 were prepared by arc type ion plating method and unbalanced magnetron sputtering method using the apparatus shown in FIG. A coating tool having the structure described in the column 24 was formed to produce a cutting tool. Hereinafter, sample No. The method for forming the coating film of the 24 cutting tool will be specifically described.

  First, an Al (70 atomic%)-Cr (30 atomic%) target was set as the first arc evaporation source 13 shown in FIG. 1, and a Ti target was set as the second arc evaporation source 14. Further, as an unbalanced magnetron sputtering source 11, an Al—Zr target was set on the magnetron electrode. The composition of the Al—Zr target was 95 atomic% for Al and 5 atomic% for Zr.

Then, after the vacuum in the apparatus 1 is evacuated to 7 × 10 ⁻⁴ Pa or less, argon is introduced from the gas inlet 15 and the base material 10 is heated to 650 ° C. while maintaining the vacuum at 3 Pa. Held for hours.

  Then, the surface of the base material 10 was cleaned by argon ions by applying a voltage of −1000 V to the base material 10 to generate glow discharge in argon. Then, argon was exhausted from the apparatus 1 after the cleaning process.

  Next, after introducing nitrogen into the apparatus 1 from the gas inlet 15, the second arc evaporation source 14 is discharged with a discharge current of 100 A while applying a voltage of −200 V to the base material 10, thereby generating an arc type. A TiN layer (the first layer of sample No. 24 in Table 4) was formed on the surface of the substrate 10 by an ion plating method.

Subsequently, the first arc evaporation source 13 is discharged with a discharge current of 80 A while a voltage of −200 V is applied to the base material 10, so that Al _0.7 Cr is formed on the surface of the base material 10 by the arc ion plating method. _{A 0.3} N layer (second layer of sample No. 24 in Table 4) was formed. Then, after forming the Al _0.7 Cr _0.3 N layer, the gas was exhausted from the inside of the apparatus 1.

Thereafter, argon and oxygen are introduced into the apparatus 1 from the gas inlet 15 and the pulsed DC with a frequency of 200 kHz is applied to the Al-Zr target as the unbalanced magnetron sputtering source 11 while maintaining the degree of vacuum at 0.3 Pa. By applying a voltage, the substrate 10 is discharged with a power of 6 kW, and a pulsed DC voltage that switches from +15 V to −200 V at a frequency of 185 kHz is applied to the substrate 10 by an unbalanced magnetron sputtering method (Al _1-x An oxide layer represented by the formula of Zr _x ) ₂ O _{3 (1 + y)} (third layer of sample No. 24 in Table 4) was formed.

  Thus, the first layer, the second layer, and the third layer shown in Table 4 were formed on the surface of the base material 10, and the base material 10 was made of cermet and cubic boron nitride sintered body 2 Sample No. 24 cutting tools were obtained.

  In Table 4, “γ + amo” in the column of the crystal structure of the third layer means that the γ-alumina type crystal structure and the amorphous structure are mixed.

  The crystal structure of the third layer in Table 4 was identified by using an X-ray diffractometer to obtain an X-ray diffraction pattern by a thin film method with an X-ray incident angle fixed at a predetermined angle.

  The column of “γ / (γ + amo)” in Table 4 shows the content ratio of the γ-alumina type crystal structure to the amorphous structure in the third layer (γ-alumina type crystal structure / (γ-alumina type). Crystal structure + amorphous structure)).

Here, the content ratio of the γ-alumina type crystal structure and the amorphous structure in the third layer (γ-alumina type crystal structure / (γ-alumina type crystal structure + amorphous structure)) No. The first layer, the second layer, and the third layer were respectively formed in this order on the base material in the same manner and under the same conditions as each of 24-28, and each of the surfaces of the manufactured third layers was observed by SEM The ratio of the area occupied by the crystal of the γ-alumina type crystal structure to the observed area of the surface of the third layer is different from the ratio of the area occupied by the crystal of the γ-alumina type crystal structure. It was determined by dividing by the sum of the proportion of the area occupied by the crystalline structure. The area occupied by the crystals of the γ-alumina type crystal structure is the total area when there are a plurality of crystals of the γ-alumina type crystal structure, and the area occupied by the amorphous structure described above. When there are a plurality of amorphous structures, the total area is defined as the total area.

  Further, “−” in the stress column in Table 4 means that compressive residual stress is generated in the layer, and the numerical value located to the right of “−” indicates the magnitude of the compressive residual stress of the layer.

  In addition, Sample No. The numerical values of “x” in the third layer of 24-28 are respectively sample Nos. It is the value calculated | required by measuring using the Rutherford backscattering method (RBS method) about the single-layer oxide layer formed on the same conditions as each of the 3rd layer of 24-28. Further, although not shown in Table 4, the sample No. The numerical values of “y” of the third layer from 24 to 28 were all in the range of −0.1 ≦ y ≦ 0.2.

(Sample No. 25)
Sample No. shown in Table 4 For the 25 coatings, the target set as each evaporation source is as follows, and the conditions such as the composition of the Al-Zr target set as the unbalanced magnetron sputtering source 11 are changed to change the first to third layers. Except for the formation, sample no. 24, and two types of sample Nos. 1 and 2 in which the base material 10 is made of cermet and cubic boron nitride sintered body, respectively. 25 cutting tools were obtained.
First arc evaporation source 13: Cr (80 atom%)-Si (20 atom%) target Second arc evaporation source 14: Ti (90 atom%)-Si (10 atom%) target (Sample No. 26)
Sample No. shown in Table 4 For the 26 coatings, the targets set as the respective evaporation sources are as follows, and the conditions such as the composition of the Al—Zr target set as the unbalanced magnetron sputtering source 11 and the introduced gas are changed to the first layer to the second layer. Except for forming three layers, Sample No. 24, and two types of sample Nos. 1 and 2 in which the base material 10 is made of cermet and cubic boron nitride sintered body, respectively. 26 cutting tools were obtained.
First arc evaporation source 13: Ti (70 atomic%)-Al (15 atomic%)-Si (15 atomic%) target Second arc evaporation source 14: Ti target (Sample No. 27)
Sample No. 2 types shown in Table 5 in which the shape of the base material is SNGN120408 (JIS-B-4121) and the base material is cermet and cubic boron nitride sintered body instead of the base material used in 1 to 23 A base material was prepared.

Then, on each base material made of cermet and cubic boron nitride sintered body, sample Nos. In Table 4 were prepared by arc type ion plating method and unbalanced magnetron sputtering method using the apparatus shown in FIG. A coating tool having the structure described in the column 27 was formed to produce a cutting tool. Hereinafter, sample No. A method for forming the coating film of the cutting tool 27 will be specifically described.

  First, an Al (65 atomic%)-Ti (30 atomic%)-Si (5 atomic%) target was set as the second arc evaporation source 14 shown in FIG. In addition, an Al—Zr target was set as the unbalanced magnetron sputtering source 11.

Then, after the vacuum in the apparatus 1 is evacuated to 7 × 10 ⁻⁴ Pa or less, argon is introduced from the gas inlet 15 and the base material 10 is heated to 650 ° C. while maintaining the vacuum at 3 Pa. Held for hours.

  Then, the surface of the base material 10 was cleaned by argon ions by applying a voltage of −1000 V to the base material 10 to generate glow discharge in argon. Then, argon was exhausted from the apparatus 1 after the cleaning process.

Next, methane and oxygen are introduced into the apparatus 1 from the gas inlet 15, and the second arc evaporation source 14 is discharged with a discharge current of 100 A while applying a voltage of −200 V to the base material 10, thereby generating an arc. An Al _0.65 Ti _0.3 Si _0.05 C _0.93 O _0.05 layer (the second layer of sample No. 27 in Table 4) was formed on the surface of the substrate 10 by the formula ion plating method. Sample No. 27 and No. described later. In 28, the 1st layer was not formed, the 2nd layer was formed as a layer which contacts a substrate, and the 3rd layer was formed as a layer located in the outermost surface.

  Thereafter, argon and oxygen are introduced into the apparatus 1 from the gas inlet 15, and a pulsed DC having a frequency of 120 kHz is applied to the Al-Zr target as the unbalanced magnetron sputtering source 11 while maintaining the degree of vacuum at 0.4 Pa. By applying a voltage, the substrate 10 is discharged at a power of 10 kW, and a pulsed DC voltage that switches from +50 V to −250 V at a frequency of 121 kHz is applied to the base material 10, so that Al, Zr, and O are obtained by unbalanced magnetron sputtering. An oxide layer (third layer of sample No. 27 in Table 4) was formed.

  As a result, the second layer and the third layer shown in Table 4 were formed on the surface of the base material 10, and the material of the base material 10 was made of two types of sample Nos. Made of cermet and cubic boron nitride sintered body. 27 cutting tools were obtained.

(Sample No. 28)
Sample No. shown in Table 4 For the coating 28, the target set as the second arc evaporation source 14 is set as follows, and the conditions such as the composition of the Al—Zr target set as the unbalanced magnetron sputtering source 11 and the introduced gas are changed. Sample No. except that layers 3 to 3 were formed. In the same manner as in Sample No. 27, two types of sample Nos. 2 were formed on the base material, and the base material 10 was made of cermet and cubic boron nitride sintered body. 28 cutting tools were obtained.
Second arc evaporation source 14: Ti (80 atomic%)-Si (20 atomic%) target (Sample No. 29)
Sample No. 1 in which the first layer, the second layer, and the third layer shown in Table 4 were formed on the surface of the substrate 10 using a conventional thermal CVD method. 29 cutting tools were obtained.

(Sample No. 30)
A Ti (50 atomic%)-Al (50 atomic%) target was set as the first arc evaporation source 13 shown in FIG. 1, and a Ti target was set as the second arc evaporation source 14.

Then, after the vacuum in the apparatus 1 is evacuated to 7 × 10 ⁻⁴ Pa or less, argon is introduced from the gas inlet 15 and the base material 10 is heated to 650 ° C. while maintaining the vacuum at 3 Pa. Held for hours.

  Then, the surface of the base material 10 was cleaned by argon ions by applying a voltage of −1000 V to the base material 10 to generate glow discharge in argon. Then, argon was exhausted from the apparatus 1 after the cleaning process.

  Next, after nitrogen is introduced into the apparatus 1 from the gas inlet 15, the second arc evaporation source 14 is discharged in a state where a voltage of −200 V is applied to the base material 10, whereby an arc ion plating method is used. A TiN layer (first layer of sample No. 30 in Table 4) was formed on the surface of the substrate 10.

Thereafter, the first arc evaporation source 13 is discharged in a state where a voltage of −200 V is applied to the base material 10, so that a Ti _0.5 Al _0.5 N layer (Table 4) is formed on the surface of the base material 10 by an arc ion plating method. Sample No. 30 of the third layer) was formed.

  As a result, the first layer and the third layer shown in Table 4 were formed on the surface of the base material 10, and the material of the base material 10 was two types of sample Nos. Made of cermet and cubic boron nitride sintered body. 30 cutting tools were obtained.

(Evaluation)
Sample No. with a coating film having the structure shown in Table 4 was formed. Using a cutting tool of 24-30, the flank wear width of the cutting tool can be reduced every minute by performing a continuous cutting test of the work material and a grooved round bar cutting test under the cutting conditions shown in Table 5. The time when the flank wear width exceeded 0.2 mm was evaluated as the life. The results are shown in Table 6. In addition, it has shown that it is a film excellent in abrasion resistance, so that the lifetime of the lifetime shown in Table 6 is long. In addition, Sample No. whose substrate is made of cermet. The cutting tools 24 to 30 were subjected to a continuous cutting test. About the cutting tools of 24-30, the round bar cutting test with a groove | channel was done.

  As is apparent from Table 6, Sample No. 1 having the composition represented by the above formula (1) and an oxide layer having a γ-alumina type crystal structure and an amorphous structure. The lifespan of the cutting tools 24 to 28 is the same as that of the sample No. having no oxide layer. It was longer than the life of 29-30 cutting tools. Considering that the cutting environment is a high temperature environment, the sample No. The wear resistance of the coatings of cutting tools 24 to 28 in a high-temperature environment is the same as that of Sample No. It was found to be superior to the 29-30 coating. In particular, sample no. 29 cutting tools were found to be defective in a grooved round bar cutting test.

  In addition, after the above-mentioned continuous cutting test and after the grooved round bar cutting test, the sample No. The welding resistance of 24-28 cutting tools was also evaluated. As a result, sample no. Since it was confirmed that the work material did not adhere to the surfaces of the cutting tools 24 to 28, sample No. It was confirmed that the coating films of 24-28 cutting tools were excellent in welding resistance in a high temperature environment.

It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  ADVANTAGE OF THE INVENTION According to this invention, the coating tool excellent in abrasion resistance and welding resistance in a high temperature environment, the cutting tool containing the coating film, and the manufacturing method of the coating film can be provided.

  DESCRIPTION OF SYMBOLS 1 apparatus, 2 cutting tool, 3 work material, 4 flank, 8 rotation holder, 10 base material, 11 1st dual magnetron sputter source or 1st unbalanced magnetron sputter source, 12 2nd dual magnetron sputter source, 13 first arc evaporation source, 14 second arc evaporation source, 15 gas inlet, 16 heater.

Claims (14)

A coating comprising at least one oxide layer,
The composition of the oxide layer is represented by the following formula (1):
(Al _1-x Zr _x ) ₂ O _{3 (1 + y)} (1)
In the formula (1), x is a real number that satisfies 0.01 ≦ x ≦ 0.07, y is a real number that satisfies −0.1 ≦ y ≦ 0.2, and
The oxide layer will have a crystalline structure and amorphous structure of γ- alumina type,
In the formula (1), x characterized real der Rukoto satisfying 0.025 ≦ x ≦ 0.04, coating. The film according to claim 1, wherein the oxide layer has a thickness of 0.05 μm or more and 20 μm or less. The oxide layer is characterized by having a 10GPa following compressive residual stress than 0.1 GPa, the film according to claim 1 or 2. The content ratio of the γ-alumina type crystal structure to the amorphous structure in the oxide layer (γ-alumina type crystal structure / (γ-alumina type crystal structure + amorphous structure)) is 10%. The film according to any one of claims 1 to 3 , wherein the film is 90% or less. Including at least one compound layer composed of nitride, carbonitride, nitride oxide, carbonate or carbonitride of at least one metal selected from the group consisting of Ti, Al, Cr, Zr and Si, The film according to any one of claims 1 to 4 . Wherein the thickness of said coating is 0.05μm or more 25μm or less, the film according to any one of claims 1 to 5. The cutting tool containing a base material and the coating film in any one of Claim 1 to 6 formed on the said base material. The cutting tool according to claim 7 , wherein the base material is high-speed steel, cemented carbide, cermet, ceramic sintered body, diamond sintered body, or cubic boron nitride sintered body.   The manufacturing method of a film including the process of forming at least 1 layer of the oxide layer of Claim 1 by PVD method. At least a compound layer made of nitride, carbonitride, nitride oxide, carbonate or carbonitride of at least one metal selected from the group consisting of Ti, Al, Cr, Zr and Si by the PVD method The manufacturing method of the film of Claim 9 including the process of forming 1 layer. The film according to claim 9 or 10 , wherein the PVD method is at least one selected from the group consisting of an arc ion plating method, an unbalanced magnetron sputtering method, and a dual magnetron sputtering method. Manufacturing method. The method for producing a coating film according to claim 11 , wherein the oxide layer is formed by the dual magnetron sputtering method, and the compound layer is formed by the arc ion plating method. The method for producing a coating according to claim 12 , wherein an Al target and a Zr target are respectively attached to a pair of magnetron electrodes used in the dual magnetron sputtering method. 12. The method for producing a coating film according to claim 11 , wherein the oxide layer is formed by the unbalanced magnetron sputtering method, and the compound layer is formed by the arc type ion plating method.

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