JP2003305601A - Hard film-coated tool and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hard film-coated tool exhibiting excellent wear resistance over a long period of time. <P>SOLUTION: This hard film-coated tool has at least a layer of a hard film formed on a metal base, having the following composition 1 or composition 2 and meeting the following requirements. Composition 1: (Ti<SB>1-a-b-c-d</SB>Al<SB>a</SB>Cr<SB>b</SB>Si<SB>c</SB>B<SB>d</SB>)(Cl<SB>-e</SB>N<SB>e</SB>) Requirements: 0.5≤a≤0.8, 0.06≤b, 0≤C≤0.1, 0≤d≤0.1, 0≤c+d≤0.1, a+b+c+d<1, 0.5≤e≤1 (where a, b, c and d are each atomic ratios of Al, Cr, Si and B, and e is the atomic ratio of N). Composition 2: (Ti<SB>a</SB>Al<SB>b</SB>V<SB>c</SB>)(C<SB>1-d</SB>N<SB>d</SB>) Requirements: 0.02≤a≤0.3, 0.5<b≤0.8, 0.05<c, 0.1≤b+c, a+b+c=1, 0.5≤d≤1 (where a, b and c are each atomic ratios of Ti, Al, and V, and d is the atomic ratio of N). <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hard film coated tool having a hard film formed on a base material, and more specifically, a hard film coated tool which exhibits excellent wear resistance over a long period of time. Regarding Incidentally, the hard coating tool of the present invention is a cemented carbide, an end mill having a base material such as cermet or high speed tool steel, a drill, a gear cutting tool such as a tip or a hob, a punch, a slitter cutter, an extrusion die, Although it can be widely applied as a jig for plastic working including a forging die and the like, a case where it is used for a cutting tool will be described below as a typical application example.

[0002]

2. Description of the Related Art Conventionally, a hard coating such as TiN, TiCN, or TiAlN is coated for the purpose of improving the wear resistance of a cutting tool based on cemented carbide, cermet or high speed tool steel. Is being done. In particular, since a composite nitride film of Ti and Al (hereinafter referred to as TiAlN) exhibits excellent wear resistance, it can be used for high-speed cutting instead of the film made of titanium nitride, carbide, carbonitride, etc. It is being applied to cutting tools for cutting hardened materials such as hardened steel.

For example, in Japanese Patent No. 3165658, in a gear machining method for forming a tooth profile by using a hob provided with a blade of high speed tool steel, (Ti _(1-x) Al _x ) ( N _y C _(1-y) ), 0.2 ≤ x ≤ 0.85, 0.25 ≤ y ≤ 1.0 If a hard coating is used, the cutting speed can be improved without using a cutting fluid. It has been shown that dry cutting can be performed at over 80 to 400 m / min.
It is shown that the abrasion resistance is the smallest in the vicinity of 1.0, and the oxidation resistance deteriorates when y becomes small.

However, the TiAlCN film is insufficient in performance for long-term use in a severe operating environment such as gear machining at a higher speed. Further, when an iron-based material such as high-speed tool steel is used as the base material, the adhesion to the TiAlCN film tends to be inferior to that of the cemented carbide base material, and thus the peeling of the TiAlCN film is suppressed. Therefore, it is necessary to improve the adhesion between the base material made of an iron-based material such as high speed tool steel and the TiAlCN film. Further, a cutting tool having a high speed tool steel as a base material, when the hard coating on the surface is worn, a chemical etching treatment is performed to remove the hard coating and then a recoating treatment, which may be repeatedly used. Since the TiAlCN film has good corrosion resistance,
There is a problem that it is difficult to remove.

Further, in Japanese Unexamined Patent Publication No. 2000-1768, 4a, 5a, 6a are provided so as to have both sliding characteristics and wear resistance.
A single or two or more layered film composed of a group and one or more elements selected from Al, Si, B and C and one or more elements selected from B, C, N and O It is shown that MoS ₂ or a compound mainly composed of MoS ₂ is formed on the formation by a sputtering method.
It has been shown that the compound mainly composed of oS ₂ should contain 0.5 to 10 at% of the elements of the 4a, 5a, and 6a groups, and that TiN, TiCN, or CrN should be used as the underlayer. There is.

In the above technique, MoS is used as the solid lubricating coating.
₂ or a compound mainly composed of MoS ₂ is used.
Since oS ₂ is a compound having a low hardness, it has a short life as a lubricating film, and as a result, the life of tools and the like is too short to withstand long-term use. In addition, TiN or Ti which is the underlayer
Since CN and CrN have low oxidation resistance and hardness, there is room for improvement when applied to cutting tools and the like that require good wear resistance.

German Patent (DE) 19816491 describes Ti, Zr, N for use in dry cutting tools and the like.
Forming a DLC (diamond-like carbon) film containing a metal element (Me) on a single-layer film or a multi-layer film of a nitride, a carbide, or a carbonitride made of one or more of b, Cr, TiAl and / or TiNb. Has been shown to
It has been shown that it is preferable to use W, Ti, Nb, Zr or Cr as the metal element (Me) and to provide a concentration gradient so that the metal component increases from the base material side to the surface.

German patent (DE) 1952355
No. 0 has TiAlN, TiAlYN or TiAlC
It has been shown that after MoS ₂ is formed on a rN single-layer film or a multi-layer film, the surface is mechanically polished so that MoS ₂ remains only in the crater portion. However, as described above, MoS ₂ has a low hardness and is inferior in adhesiveness to the base material, and therefore cannot exhibit excellent sliding characteristics.

US Pat. No. 5,707,748 proposes a tool in which a hard coating layer is provided on a base material, and a mixed layer of metal carbide and C (carbon) is formed as a friction coefficient reducing layer on the hard coating layer. It is disclosed that the average particle size of the hard coating layer and the friction coefficient reducing layer is 1 μm or less, and the thickness of the friction coefficient reducing layer is not more than the thickness of the hard coating layer. The hard coating layer is essentially composed of nitride, carbide, or carbonitride of Ti, Hf, Zr or their alloys, and the friction coefficient reducing layer is W or Cr.
Is included, and in the case of the W-C combination, C
It is suggested that the amount should be 61 atomic% or more.

However, the above technique has not been sufficiently studied for hard coatings, and in order to further improve the wear resistance of the tool, it is necessary to further improve the hard coatings in response to the demand for high-speed and high-efficiency machining. Will need to be examined.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and its purpose is to achieve high speed
A hard film coating tool capable of high-efficiency processing and exhibiting wear resistance superior to known TiAlCN films for a long period of time, and a hard film coating suitable for tools repeatedly used after removing the used film. When performing dry or semi-dry processing on tools and materials that are easily welded, such as iron-based alloys, aluminum-based alloys, and titanium-based alloys,
It is an object of the present invention to provide a hard film-coated tool that enables efficient cutting over a long period of time and a useful manufacturing method for obtaining such a hard film-coated tool.

[0012]

The hard coating tool according to the present invention is characterized in that at least one hard coating satisfying the requirements of the following composition 1 or composition 2 is formed on a metal substrate. The residual compressive stress of the hard coating is preferably 8 GPa or less.

[0013] <Composition _{1> (Ti 1-abcd Al} a Cr b Si c B d) (C
_1-e N _e ) 0.5 ≦ a ≦ 0.8, 0.06 ≦ b, 0 ≦ c ≦ 0.1, 0 ≦ d ≦ 0.1, 0 ≦ c + d ≦ 0.1, a + b + c + d <1, 0.5 ≦ e ≦ 1 (a, b, c and d represent the atomic ratios of Al, Cr, Si and B, respectively, and e represents the atomic ratio of N. The same applies hereinafter.)

<Composition 2> (Ti _a Al _b V _c ) (C _1-d N _d ) 0.02 ≦ a ≦ 0.3, 0.5 <b ≦ 0.8, 0.05 <c, 0 .7 ≦ b + c, a + b + c = 1, 0.5 ≦ d ≦ 1 (a, b, and c represent atomic ratios of Ti, Al, and V, and d represents atomic ratio of N. The same applies hereinafter).

It is preferable that at least one layer of a first intermediate film satisfying the following composition is formed between the metal substrate and the hard film. (Ti _1-x Al _x ) (C _1-y N _y ) 0 ≦ x ≦ 0.25, 0.5 ≦ y ≦ 1 (x represents the atomic ratio of Al and y represents the atomic ratio of N. same as below)

It is also a preferred embodiment of the present invention that at least one metal layer or alloy layer containing Ti and / or Cr is previously formed as a second intermediate film on the surface of the metal base material.

Further, the present invention also includes a hard coating tool in which a solid lubricating film having a wear coefficient for the material to be processed smaller than that of the hard coating for the material to be processed is formed as the outermost surface coating. As the solid lubricating film, W, C
at least 1 selected from the group consisting of r, Ti, and Mo
It is preferable to use the one containing 30% by atom or less of the seed and the balance being mainly C.

The hard film-coated tool having the solid lubricating film thus formed is useful when an iron-based alloy, an aluminum-based alloy, a titanium-based alloy or a copper-based alloy is used as a workpiece, and
When used as a tool for dry cutting or semi-dry cutting, the characteristics can be sufficiently exhibited.

An iron-based alloy base material can be used as the metal base material, and preferably an iron-based alloy base material tempered at 500 ° C. or higher is used. Further, when forming the solid lubricant and applying it to a tool such as a drill, it is preferable to use a cemented carbide base material as the metal base material.

The hard coating tool of the present invention is particularly suitable for hobs,
It can be seen that when used for a cutting tool such as a drill or an end mill, it exhibits superior wear resistance over a long period of time as compared with a conventional cutting tool.

In producing a hard film-coated tool whose base material is an iron-based alloy base material, an arc ion plating method is adopted, and the base material temperature is set within the range of 350 ° C to 520 ° C. Forming is recommended from the viewpoint of ensuring the mechanical properties of the tool.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, as a jig for plastic working for which higher speed and higher efficiency are required, it is excellent if a hard coating defined on a metal base material is used. It was found that the wear resistance was exhibited for a long time.

Further, stress control is important in order to further improve the adhesion between the hard coating and the metal substrate, and in order to secure the optimum stress state, it suffices to control the manufacturing method of the coating and the intermediate point of the regulation. It was found that a film should be formed.
Further, it has been found that the intermediate film defined in the present invention may be provided in order to facilitate the removal and recoating of the used film so that the tool can be repeatedly used.

Further, by forming a specified solid lubricating film on the hard film of the present invention, the conventional Ti film can be used even in a severe environment.
It was found that the wear resistance superior to that of the AlCN film can be exhibited for a long time, and the present invention was conceived.

Hereinafter, the coating and the base material constituting the tool in the present invention, and the reason for defining the preferable manufacturing conditions for forming the coating (film formation) will be described.

[0026] <Regarding hard film> The present inventors have, Ti of a conventionally known _{(Ti (1-x) Al} x) (N y C (1-y)) film (hereinafter, abbreviated as TiAlCN film) It has been found that if a part of the above is replaced with Cr or V, and Si and B are added if necessary, the hardness becomes higher than that of the TiAlCN film, and the cutting characteristics are remarkably excellent, and the application has already been made. Japanese Patent Application No. 2001-287587, etc .: However, unpublished).

The characteristics of these films are that a part of Ti is Cr
Alternatively, by substituting with V, it is possible to maintain a higher Al concentration and realize a cubic rock salt type structure having a high hardness phase. For example, in the case of the TiAlCN film, the content of A
It is known that the amount of 1 is limited to 60 to 65 atom% (ratio in the metal component), and if it exceeds the limit, the structure is transformed into a hexagonal crystal having a soft structure. On the other hand, the film of the present invention is A
Even if the amount of 1 is 60 atomic% or more, and further 65 atomic% or more, the cubic rock salt type structure can be maintained, and as a result, a film of high hardness can be obtained. The reasons for defining the composition of the hard coating to be coated on the tool of the present invention will be described below.

Regarding "composition 1" of the hard coating, TiAlN is a crystal of rock salt structure type and T of rock salt structure type.
It is a rock salt structure type composite nitride in which Ti site of iN is substituted with Al. Since rock salt structure type AlN is a high temperature and high pressure phase, it is expected to be a high hardness material. Therefore, if the ratio of Al in TiAlN is increased while maintaining the rock salt structure, the hardness of the TiAlN film can be increased. However, since rock salt structure type AlN is a non-equilibrium phase at room temperature and normal pressure and high temperature and low pressure, normally only soft ZnS type AlN is generated even if vapor phase coating is performed, and rock salt structure type AlN simple substance is generated. I can't.

However, since TiN is a rock salt structure type and has a lattice constant close to that of rock salt structure type AlN, if Al is added to Ti to form a nitride film, AlN is drawn into the structure of TiN and is kept at room temperature. Rock salt structure type TiA under high pressure and high temperature and low pressure
It is possible to generate 1N. However, as described above, when the composition ratio x of Al when TiAlN is expressed as (Al _x , Ti _1-x ) N exceeds 0.6 to 0.7,
The pulling effect of TiN is weakened and soft ZnS-type AlN precipitates.

By the way, since the lattice constant of CrN is closer to that of rock salt structure type AlN than that of TiN, the Ti of TiAlN is
By partially substituting Cr with Cr, the ratio of rock salt structure type AlN can be further increased. If the ratio of rock salt structure type AlN in the film can be increased by adding Cr in this way, the hardness can be made higher than that of the TiAlN film.

On the other hand, by adding Si to TiAlN, the hardness,
Japanese Patent Application Laid-Open No. 7-310174 discloses that oxidation resistance is improved. In this publication, Al is used in an atomic ratio of 0.
75 or less, and the atomic ratio of Si is specified to be 0.1 or less,
It has been shown that when Al and Si exceed the above range, the film changes to a soft hexagonal structure, so that it is impossible to further increase the oxidation resistance. The present inventors
It has been found that by adding Cr and further Si to the 1N film, it is possible to improve the oxidation resistance and increase the hardness while maintaining the rock salt structure type. Si
Although a detailed analysis has not been made on the behavior of the above, it is presumed that the behavior is similar to that of Al in TiAlN described above, that is, the TiN lattice is substituted with the Ti lattice position.

Since AlN, CrN and Si-N compounds also have better oxidation resistance than TiN, it is necessary to reduce the proportion of Ti and add Al, Cr and Si from the viewpoint of improving the oxidation resistance. Is preferred.

The (Ti _1-abcd Al _a C of the present invention is described below.
r, _{B, c, Bd} ) (C _{1-e Ne} ) Ti, A constituting the film
a depending on the atomic ratio of 1, Cr, Si, B, C and N,
The reason for defining b, c, d and e will be described in detail.

First, for Al, the lower limit of the atomic ratio a was set to 0.5 in order to secure oxidation resistance and hardness. The upper limit of the atomic ratio a of Al is set to 0.8 because if it exceeds this, soft hexagonal crystals are precipitated and the hardness of the film is reduced.

By adding Cr, the Al content can be increased while maintaining the rock salt structure type as described above, and in order to exert such an effect, the lower limit of the atomic ratio b of Cr is set. It was set to 0.06.

The atomic ratio a of Al is preferably 0.55 or more, more preferably 0.60 or more. The lower limit of the atomic ratio b of Cr is preferably 0.08. FIG. 1 is a composition diagram of the metal components Ti, Al and Cr in the (Ti, Al, Cr) N film. The Cr atomic ratio (b) = 4 (Al atomic ratio -0 in FIG. 1). .75) on the left side, that is, when the Cr atomic ratio (b) <4 (Al atomic ratio -0.75), the crystal structure of AlN in the film is a soft ZnS type ratio even if Cr is added. , The hardness of the film decreases sharply.
Therefore, when the atomic ratio a of Al exceeds 0.765, the ratio of the Cr atomic ratio (b) is b ≧ 4 (Al atomic ratio-
0.75) is preferable. CrN has a smaller hardness than TiN, and if added excessively, the hardness is lowered. Therefore, the upper limit of the atomic ratio b of Cr is preferably 0.35, and more preferably 0.3.

Si has the effect of improving the oxidation resistance as described above, and B has the same effect. Therefore, from the viewpoint of improving the oxidation resistance, Si and / or B have an atomic ratio (c + d). It is preferable to add 0.01 or more.
More preferably, it is 0.02 or more. On the other hand, if the proportion of Si and / or B is too large, a soft hexagonal crystal structure is deposited and the wear resistance is impaired.
The atomic ratio of: c, d or the upper limit of (c + d) is 0.1. It is preferably 0.07 or less, more preferably 0.05 or less.

The Si-N compound has a function of forming a protective coating of Si oxide in a high temperature oxidizing atmosphere and protecting the coating from oxidation. However, the BN compound itself has excellent oxidation resistance ( When the oxidation start temperature is around 1000 ° C.), the formed oxide has a small protective effect and is slightly inferior in effect to the addition of Si. Therefore, it is preferable to add Si rather than B, and it is recommended to add only Si as a more preferable form.

The amount of Ti depends on the above Al, Cr, Si and B.
Although it is determined by the amount, TiN has a higher hardness than CrN, and if Ti is not added at all, the hardness of the film decreases. Therefore, the atomic ratio of Ti (1-a-b-c-
The lower limit of d) is preferably 0.02, more preferably 0.03. Further, when the atomic ratio of Al is set to 0.6 or more, if Ti is excessively added, the amount of Cr becomes relatively small and the pulling effect becomes small,
In this case, the atomic ratio of Ti is preferably 0.35 or less, and more preferably 0.3 or less.

When Si and B are not added, that is, (c +
When the value of d) is 0, it is recommended that the atomic ratio of Ti, Al and Cr be within the following range as shown by the solid line in FIG. That is, 0.02 ≦ 1-ab−0.30, 0.55 ≦ a ≦ 0.765, 0.06 ≦ b, or 0.02 ≦ 1-ab−0.175, 0.765 It is effective to satisfy ≦ a and 4 (a−0.75) ≦ b.

When the atomic ratio of Ti is less than 0.20, the oxidation resistance is further improved, a higher oxidation starting temperature is exhibited, and more excellent oxidation resistance can be secured. Therefore, within the range of a and b defined above, 0.02 ≦ 1-ab−0.20, 0.55 ≦ a ≦ 0.765, 0.06 ≦ b or 0.02 ≦ 1-a It is preferable that -b <0.20, 0.765≤a, and 4 (a-0.75) ≤b.

Further, by setting the atomic ratio b of Al to be 0.6 or more and limiting the upper limit of the atomic ratio of Al to the region where the crystal structure of the film is almost a single phase of rock salt structure, Si and B are not contained. Even if not only oxidation resistance but also TiA
Among 1N (0.56 ≦ Al ≦ 0.75), it is possible to obtain a hardness higher than that of Ti _0.4 Al _0.6 N, which has the highest hardness.

Therefore, the most preferable ranges of a and b are 0.02 ≦ 1-a−b <0.20, 0.60 ≦ a ≦ 0.709, or 0, as shown by the broken line in FIG. .02 ≦ 1-ab−0.20, 0.709 ≦ a, and 11/6 × (a−0.66) ≦ b.

As described above, CrN has a smaller hardness than TiN, and if added excessively, the hardness is lowered. Therefore, even in these preferable ranges, the atomic ratio b of Cr is b.
The upper limit of is preferably 0.35, more preferably 0.3.

By the way, by adding C to the film,
It is possible to increase the hardness of the film itself by precipitating a high-hardness carbide such as TiC, SiC, or B ₄ C. Therefore, it is desirable that the C atomic ratio (1-e) be the same as the total atomic ratio of Ti, Si, and B (1-a-b).
However, if added excessively, chemically unstable Al
₄ C ₃ and Cr ₇ C ₃ will be deposited, and the oxidation resistance will be likely to deteriorate. Therefore (Ti _1-abcd Al _{a
Cr b Si c B d) (} C 1-e N e) the value of e in is 0.
Make it 5 or more. The value of e is preferably 0.7 or more, more preferably 0.8 or more, and most preferably e = 1.

Regarding "Composition 2" of Hard Film Next, the reason for defining "composition 2" of hard film will be described.

Both Al and V are elements that bring about the effect of increasing the hardness, and in order to exert such effects, the atomic ratio b of Al exceeds 0.5 and the atomic ratio c of V is 0. It is necessary that the total atomic ratio (b + c) of (Al + V) is 0.7 or more in addition to more than 05. The atomic ratio b of Al is preferably 0.55 or more, more preferably 0.6 or more, and the atomic ratio c of V is preferably 0.06.
Above, it is more preferably 0.1 or more. Furthermore (Al
The total atomic ratio (b + c) of + V is preferably 0.75 or more, and more preferably 0.8 or more.

The reason for defining the upper limit of the atomic ratio of Al is as follows. That is, if the atomic ratio of Al becomes too large, ZnS type AlN that is stable at room temperature and atmospheric pressure becomes dominant, and the structure of the coating will completely transform from the rock salt type that can maintain high hardness to the soft ZnS type. From 0.
It must be 8 or less, preferably 0.75 or less. The upper limit of the atomic ratio c of V is preferably 0.4.

Regarding the amount of Ti, as described above (Al +
Since it is necessary to set the atomic ratio of V) to 0.7 or more,
The atomic ratio a of Ti needs to be 0.3 or less, but when the (b + c) is 0.75 or more, it is preferably 0.25 or less, and more preferably 0.2 or less. . On the other hand, if Ti is not added at all, it is not possible to achieve high hardness by solid solution of crystals (TiN and VN, TiN and AlN) having different lattice constants as described above, and therefore Ti has an atomic ratio of 0. 02 or more is necessary, and 0.05 or more is desirable in order to maximize the solid solution hardening.

Further, the amounts of C and N are as follows. That is, when C is added to the film to precipitate high hardness carbides such as TiC and VC to increase the hardness of the film,
It is desirable that C be present in the same amount as the amount of Ti + V added. However, if C is excessively added, unstable aluminum carbide that easily decomposes by reacting with water as described above is excessively precipitated, so that the atomic ratio (1-d) of C is 0.5. Or less, that is, the atomic ratio d of N is 0.5
It is necessary to be above. d is preferably 0.7 or more, more preferably 0.8 or more, and d = 1 is the most preferable form.

In the present invention, in addition to the case where the hard coating film satisfying the above composition 1 or composition 2 is formed as a single layer on the substrate, it satisfies the range of composition 1 or composition 2.
The present invention also includes a tool in which two or more hard coatings having different compositions or different hard coatings having different crystal orientations are formed on the base material.

Whether the hard coating is a single layer or a plurality of layers, the total thickness is preferably about 1 to 5 μm. If it is too thin, good abrasion resistance will not be exhibited, while if it is too thick, the film will be broken or peeled during cutting. A more preferable film thickness is about 3 to 4 μm.

<Regarding the First Intermediate Film> Furthermore, in the present invention, (Ti _1-x Al _x ) (C _1-y N _y ) 0 ≦ x ≦ 0.25, 0 between the hard coating and the metal substrate. .5 ≦ y ≦ 1 (x represents the atomic ratio of Al and y represents the atomic ratio of N)
It is preferable that at least one layer of the film (hereinafter, simply referred to as “first intermediate film”) is formed from the viewpoint of improving the adhesion between the hard film and the substrate.

The Young's modulus of iron-based materials such as high speed tool steel or hot work tool steel generally used as a base material is about 200 G.
Although the hardness is about Pa, the Young's modulus of the hard coating specified in the present invention is a value near 450 GPa, which is about 1.5 times higher than that of conventional TiAlN. When cutting is performed using a tool in which a film with a Young's modulus that greatly differs is formed on the base material, the elastic deformation behavior of the cutting film and the base material when external stress is applied is significantly different. In some cases, the hard coating cannot follow the deformation of the base material and the coating may peel off.

In the present invention, by providing the first intermediate film showing the intermediate value of Young's modulus of the base material and the hard coating, stress relaxation in the hard coating portion under external stress load is achieved, and as a result, excellent adhesion is obtained. I was able to get it. When the first interlayer film is TiN, the Young's modulus of the interlayer film is about 30.
It is 0 GPa, and Young's modulus tends to increase with increase in Al, but the upper limit amount of Al atomic ratio is 0.25.
In this case, the Young's modulus is about 350 GPa, which is closer to that of the base material than the hard coating. As described above, the upper limit of the amount of Al in the first interlayer film is defined.
This is because the Young's modulus increases with an increase in the amount, and when the Al atomic ratio (x) exceeds 0.25, the Young's modulus of the intermediate film increases and the stress relaxation effect cannot be expected. The upper limit of the Al atomic ratio (x) is preferably 0.2, and more preferably 0.1.

By the way, since the Ti-Al nitride film and the carbonitride film tend to increase the electric resistance and the corrosion resistance of the film as the Al content increases, it is necessary to re-coat and repeatedly use the tool. When the used film is removed by utilizing an electrochemical reaction (hereinafter sometimes simply referred to as “film removal”), the film tends to be difficult to remove. The hard coating of the present invention is desirable to add 60 atomic% or more of Al. Since it has high corrosion resistance, it is removed as compared with the conventional TiAlCN film having a small amount of Al and low corrosion resistance and electric conductivity. Membrane is difficult.

In the present invention, if the first intermediate film having an Al content of 0.25 or less in atomic ratio is provided between the base material and the substrate, the first intermediate film can be preferentially dissolved in the film removing step. It was found that it was possible to easily remove the film from the substrate. If the Al atomic ratio (x) of the first intermediate film exceeds 0.25, the electric resistance of the film increases, and an Al oxide film that is difficult to dissolve is formed in the film removing step, which makes treatment difficult, which is not preferable. .

When C (carbon) is added to the first intermediate film, the corrosion resistance of the film can be slightly decreased and the electric resistance can be decreased, and the film removal can be efficiently performed. It is preferable that the ratio of atomic ratio in the total of is 0.5 or less.

The thickness of the first intermediate film is preferably within the range of 0.1 to 2 μm. If the film thickness is less than 0.1 μm, the stress relaxation effect cannot be expected. On the other hand, if it exceeds 2 μm, most of the film on the substrate, which is usually about 3 to 5 μm, is not covered with the first film.
This is because the intermediate film occupies a small proportion of the hard film, and good wear resistance cannot be ensured.

<Second Intermediate Film> For the purpose of improving the adhesion between the base material and the hard coating, a metal layer containing Ti and / or Cr as a second intermediate film on the surface of the metal base material in advance. Alternatively, at least one alloy layer is formed and the second
The hard coating or the first intermediate coating is formed on the intermediate coating so that the structure is base material-second intermediate coating-hard coating or base material-second intermediate coating-first intermediate coating-hard coating. You may

The second intermediate film does not contain nitrogen and does not contain Cr or T.
Since i does not exist in the state of a compound such as a nitride, it forms a strong metal bond (Fe-Ti compound, Fe-Cr compound) with Fe, which is the main component of the base material when the second intermediate film is formed, Improves adhesion to the substrate. The second
Since Cr and Ti of the intermediate film are elements that easily react with nitrogen, the adhesion to the hard film specified in the present invention and the nitride film and carbonitride film such as the first intermediate film is also good.

The thickness of the second intermediate film is preferably within the range of 0.01 to 1 μm. If the thickness is less than 0.01 μm, the effect of improving the adhesiveness is not recognized, while if it exceeds 1 μm, the second intermediate film occupies most of the film on the substrate as in the case of the first intermediate film. This is because the ratio of the hard coating is reduced and good wear resistance cannot be secured.

<Residual compressive stress of hard coating> It is desirable that the residual compressive stress of the hard coating is 8 GPa or less. This is because if the residual compressive stress of the hard coating exceeds 8 GPa and is too high, peeling of the hard coating is likely to occur when external stress is applied while the tool is being used for cutting or the like.

This residual compressive stress is determined by utilizing X-ray diffraction to obtain a specific peak of the hard coating [eg rock salt structure type (11
1), (200) plane], the incident angle ψ of the X-ray with respect to the sample surface is changed, the shift of the peak position is measured, and the shift can be derived from the following formula (1). Stress (GPa) = − E / 2 (1 + ν) ・ cotθ ₀・ π / 180 ・ δ (2θ) / δ (sin ² ψ)… (1) [In formula (1), E: Young's modulus of hard film (= 450 GPa) ν: Poisson's ratio of hard coating (= 0.22) θ ₀ : Standard Bragg angle δ (2θ) / δ (sin ² ψ): Diffraction angle of sin ² ψ of ψ angle of focused diffraction line Slope of graph plotting (2θ)]

<Solid Lubrication Film> In the present invention, the outermost surface film is formed by forming a solid lubrication film having a wear coefficient smaller than the wear coefficient of the hard coating on the work material, thereby improving the durability of the tool. Conventional TiAlCN
It can be remarkably superior to the membrane.

The TiAlCN film, which is a conventional hard film, is
The friction coefficient is about 0.5 to 0.7 with respect to a work material such as an iron-based alloy, an aluminum-based alloy, a titanium-based alloy or a copper-based alloy, whereas the hard coating of the present invention is slightly lower than this. 0.
Although it is about 4 to 0.6, in the actual cutting environment,
The work material or the chips of the work material easily adhere to the tool. Therefore, it is desirable to form a solid lubricating film having a small friction coefficient as the outermost surface film in order to reduce the welding of the work material and the chips and prolong the life of the tool.

As the solid lubricating film, W, Cr, T
i, 3 at least one selected from the group consisting of Mo
It is recommended to form a film containing 0 atomic% or less and the balance being mainly C.

The conventional MoS ₂ coating or the coating mainly composed of MoS ₂ to which a metal element is added has a low friction coefficient of about 0.1 to 0.2 with respect to various materials, but the solid lubrication of the present invention. Since the hardness is lower than that of the film (the hardness of the solid lubricating film of the present invention is HV 1500 or more, whereas the hardness of the MoS ₂ (main) film is about HV 1000), sliding with the work material or chips As a result, the film disappears easily and the effect does not continue. On the other hand, since the solid lubricating film of the present invention has a high hardness to some extent, it is possible to maintain the lubricating effect during long-term use.

As a method of measuring the friction coefficient, for example, a sliding reciprocating abrasion friction tester (ball-on-disk type) is used, and a film is formed on a ball (cemented carbide, HSS, etc.) The material to be processed may be used as the material. At this time, the test condition is, for example, load: 1.96.
N, sliding speed: 20 mm / sec, and it is recommended to measure the friction coefficient after sliding for a distance of about 50 to 100 m.

W, Cr, T contained in the solid lubricating film
The upper limit of the total amount of i and Mo is 30 atom%. This is because if these elements are excessively contained, the friction coefficient increases to 0.3 or more, and the desired lubricating effect cannot be obtained. More preferably, it is 20 atomic% or less in total. On the other hand, the lower limit of the element addition amount may be appropriately set according to the work material and cutting conditions, but when the work material is iron-based, titanium-based or copper-based, the resistance during cutting is large, As a result, a large load is applied to the solid lubricating film. Therefore, in order to secure the toughness of the solid lubricating film, it is desirable to add the metal element in a total amount of 5 atomic% or more. When the material to be processed is an Al-based material, the performance is similar if the total amount of the metal elements is approximately 20 atomic% or less.

The balance of the solid lubricating film of the present invention is mainly C. Specifically, for example, diamond-like carbon (DLC), hydrogen-free ta-C (tetrahedral amorphous carbon), Examples include aC: H (hydrogenated amorphous carbon) and the like.

In principle, the metal element used for forming the solid lubricating film is selected from the elements not contained in the material to be processed, from the viewpoint of reducing the affinity with the material to be processed and reducing the friction coefficient. desirable. That is, for example, if the work material is Ti
In the case of a base alloy, it is preferable to avoid using a tool provided with a solid lubricating film to which Ti is added and use a tool to which an element other than Ti is added to the solid lubricating film. The work material is C
In the case of an iron-based material containing r, it is desirable to use W or Mo as the metal element because the friction coefficient can be further reduced.

It is recommended that the thickness of the solid lubricating film is about 0.5 to 2 μm. If it is too thin, the desired lubricating effect is not sufficiently exhibited, while if it exceeds 2 μm and is too thick, the proportion of the solid lubricating film in the coating becomes large, and the characteristics of the hard coating are not fully exhibited.

In order to improve the adhesion between the solid lubricating film and a film such as a hard film, W, Cr, Ti, M are added between them.
A functionally gradient film in which a metal film made of one type selected from the group consisting of o or an alloy film made of two or more types is provided, or the C content is continuously or stepwise increased from the metal intermediate layer to the solid lubricating film. May be provided.

As described above, the tool of the present invention having the cutting film formed thereon and the solid lubricating film formed thereon is not limited to cutting in a wet environment using a lubricant, and in consideration of recent environmental problems. Even in dry cutting or semi-dry cutting with a minimum amount of lubricant, TiAl (CN) films and Ti that have been used as hard coatings until now.
Compared with the case where an Al (CN) film is coated with a solid lubricating film, it exhibits remarkably excellent durability performance.

<Substrate> The substrate constituting the hard coating tool of the present invention is not particularly limited as long as it is a metallic substrate, but SKH51, SKD61, SK.
An iron-based alloy base material such as D11 is preferably used.

When the film is formed, the temperature of the iron-based material is kept at about 480 ° C.
When film formation is performed at a high temperature, the base material temperature fluctuates slightly around 480 ° C. in actual operation, so tempering is performed at 500 ° C. from the viewpoint of maintaining the mechanical properties of the base material.
The iron-based alloy material obtained as described above is preferably used as the base material.

Further, as the metal base material, a cemented carbide base material whose hard phase is tungsten carbide, titanium carbide or the like and whose metal phase is cobalt or the like can be used.

<Applications> The hard film-coated tool of the present invention is not particularly limited in its application, and as described above, a gear cutting tool such as an end mill, a drill, a tip or a hob, a punching punch, a slitter cutter, an extrusion die. It can be used as a plastic working jig including a forging die and the like, but is particularly recommended when it is used as a gear cutting tool such as an end mill, a drill, a hob, etc., because the effect becomes more remarkable. The above gear cutting tool is used at a higher speed for a longer period of time, and because the usage environment is extremely severe compared to other tools such as chips, it is superior to the case where a conventional tool is used. It shows durability performance.

In particular, it is recommended to apply a coating obtained by combining the hard coating defined in the present invention and the solid lubricating coating to the coating formed on the drill. The chips are likely to be discharged in the turning process using the end mill or the tip, whereas the chips are likely to be clogged in the cutting hole in the drilling process, and the drill is likely to be damaged due to the clogging of the chips. This tendency is remarkable when the work material is carbon steel, aluminum-based alloy, copper-based alloy, titanium-based alloy in which chips are not easily discharged, or when the depth of the hole exceeds twice the diameter of the drill. is there. A drill formed with a film combining the hard film and the solid lubricating film of the present invention,
In cutting such a work material that is easily clogged with chips, it is possible to satisfactorily perform cutting even when the machining hole depth / tool diameter exceeds twice, and such severe cutting is performed. It can be used for a long time under the usage environment. In particular, when the processed hole depth / tool diameter exceeds 3 times, the excellent properties of the drill having the film of the present invention are remarkably exhibited as compared with the conventional drill having the film.

<Regarding the method for forming the film of the present invention> Examples of the method for forming the hard film, the first intermediate film, the second intermediate film and the solid lubricating film of the present invention include sputtering and arc vapor deposition. The cathode discharge type arc ion plating method in the arc vapor deposition method is recommended for the formation of the hard coating because the film formation rate is high and the productivity can be improved.

When the hard coating is formed by the above-mentioned sputtering method or arc vapor deposition method, the reaction between the hard coating and the substrate can be promoted by heating the base material during the film formation, and the adhesion can be improved. It is possible to improve, densify the film, and increase hardness. Substrate temperature during hard film formation is 350-5
It is preferable that the temperature is within the range of 20 ° C. This is because if the substrate temperature is too low, the hard coating formed is not dense and the adhesion is unfavorable. On the other hand, if the substrate temperature is too high, the tempering temperature of the substrate may be exceeded, which is not preferable.
A more preferable base material temperature at the time of forming the hard film depends on the tempering temperature of the base material, but is in the temperature range of 450 to 500 ° C.

Further, as a result of pursuing the characteristics of the hard coating by the present inventors, the coefficient of thermal expansion of the hard coating is 9 to 10 × 10 ⁻⁶ / ° C.
It was found that the degree of thermal expansion was less than 12 × 10 ⁻⁶ / ° C. of the iron-based alloy such as HSS used as the base material. Therefore, after film formation at a temperature higher than room temperature, the shrinkage of the material that occurs in the process of cooling to near room temperature is larger in the base material than in the hard coating, and as a result the compressive residual stress due to the difference in thermal expansion coefficient is hard. If the compressive residual stress is generated in the film and is too large, it causes the peeling of the hard film as described above. In the present invention, the substrate temperature during film formation is 520 ° C.
The compressive residual stress of the hard coating that occurred can be reduced by setting the temperature below not too high.

When forming a solid lubricating film to which C (carbon) and a metal element are added, (solid C target) + (metal target) is used as a target, and the sputtering method is used instead of the arc ion plating method. Is recommended. The reason is that in the arc ion plating method, the solid C target tends to have a non-uniform discharge state, which makes it difficult to form a stable film, and as a result, the film thickness, components, etc. may become non-uniform. is there.

[0085]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples, and may be appropriately applied within a range compatible with the gist of the preceding and the following. Modifications can be made and implemented, and all of them are included in the technical scope of the present invention.

Example 1 Using the cathode discharge type arc ion plating device shown in FIG. 2, Ti--Cr--
Al target 6, Ti-V-Al target 6, Ti
Using -Cr-Al-Si target 6 or Ti-Al target 6 (for conventional hard film formation), Table 1
Nitride film or carbonitride film (composition:
(About 3 μm) was formed on the substrate W, and the hardness and wear resistance of the obtained film were evaluated.

A high speed tool steel (JIS-S
A square end mill (two blades, diameter 10 mm) made of KH51 tempering temperature: 550 ° C., and chips made of the same high speed tool steel (JIS-SKH51 tempering temperature: 550 ° C. hardness: HV850) for analysis were used.

Film formation and evaluation of characteristics were performed as follows. That is, after the substrate is introduced into the apparatus, it is the substrate temperature (temperature during film formation. The maximum temperature of the substrate is 520 ° C. even in the preheating step and the ion cleaning step after the introduction into the apparatus.
It is the following. The same applies to the following examples), and the degree of vacuum is set to 4 × 10 ⁻³ Pa or less, and then cleaning with Ar ions is performed (Ar pressure: 2 Pa,
Substrate voltage: 400V). After the cleaning is completed, nitrogen is introduced so that the inside of the apparatus becomes about 3 Pa, the arc current is 100 to 150 A, and the substrate voltage is -1 with respect to the ground potential.
The film was formed at a voltage of 00 to -150V. After that, the sample was taken out, and the composition of the film coated on the chip was analyzed. Also, the film on the chip was partially scraped off to examine the hardness of the base material. Further, the following cutting test was performed using a coated end mill, and the wear resistance of the coating was evaluated by the wear amount of the tip portion after the test. The results are shown in Table 1.

<End mill cutting test> Work Material: SKD61 (HRC40) Cutting speed: 100m / min Notch: 0.5 mm Blade feed: 0.08 mm / blade Cutting length: 30m Others: Dry cut air blow

[0090]

[Table 1]

From Table 1, No. It can be seen that in Nos. 6 to 9, the hard film formed satisfies the requirements of the present invention, and thus the end mill has a small amount of wear and is excellent in wear resistance.

On the other hand, in No. It can be seen that the coatings formed by 1 to 5 are hard coatings that have been used conventionally or coatings that do not meet the requirements of the present invention, so that the end mill wears a large amount and is not excellent in wear resistance.

[Example 2] In Example 2, the adhesion between the base material and the hard coating when the first intermediate film and the second intermediate film defined in the present invention were formed between the base material and the hard coating. And the ease of film removal was investigated.

A cathode discharge type arc ion plating apparatus similar to that in Example 1 was used to form a film. In this example, in order to form the first intermediate film and the second intermediate film in addition to the hard film, a plurality of evaporation sources (targets) not shown in FIG. 2 were installed to form the film. That is, to form a hard film, Ti-Cr-Al (atomic ratio 10: 1
8:72) A target or a Ti—Al target (for forming a conventional hard film) is used, and T is used for forming the first intermediate film.
An i-Al target (a target having a composition different from that used for forming the hard film is also used) or a Ti target is used, and a Cr or Ti target is used for forming the second intermediate film (metal film). Hard films and intermediate films having the compositions shown in Table 2 were formed on the substrate. High speed tool steel (J
Chips made from IS-SKH51 tempering temperature: 550 ° C.) were used.

Film formation and evaluation of characteristics were performed as follows. That is, after introducing the substrate into the apparatus, the substrate temperature was set to 480 ° C., the degree of vacuum was set to 4 × 10 ⁻³ Pa or less, and then cleaning was performed using Ar ions (Ar pressure: 2 Pa, substrate voltage: 400 V). After the cleaning is completed, nitrogen is introduced so that the inside of the apparatus becomes about 3 Pa, and the arc current is 100 to
150A, substrate voltage -100 to-
First intermediate film having a thickness of about 1 μm and a thickness of about 3 μ at 150 V
m hard coating was formed. The thickness of the metal film formed as the second intermediate film was about 0.1 μm.

A scratch test was carried out using the chip thus formed with the coating film to evaluate the adhesion. In the scratch test, a diamond indenter (radius 200 μmR)
10 mm in length (final load 100) while increasing the load on the sample surface at a load increasing rate of 10 N / mm.
N), the scratch mark was observed with an optical microscope, and the load at the time when film peeling occurred was defined as the peeling load. Further, in order to examine the peeling property of the film (easiness of film removal), the film was subjected to a peeling treatment in the following aqueous solution, and the ease of film removal was evaluated by the time until the film was completely peeled (peeling time).

<Peeling condition> Treatment solution: Hydrogen peroxide water (concentration 20%, pH 9) Solution temperature: normal temperature

[0098]

[Table 2]

From Table 2, in the case where the hard coating of the present invention is formed (No. 2), the adhesion between the base material and the hard coating is better than in the case where the conventional hard coating is formed (No. 1). It has excellent properties, but no. As shown in 3 to 8, by forming the first interlayer film defined in the present invention between the base material and the hard coating, the adhesion between the base material and the hard coating can be further enhanced, and it can be used repeatedly. It can be seen that the removal of the film becomes easier. Incidentally, No. 3 to 6 and No. Comparing Nos. 7 and 8, it can be seen that it is preferable that the composition of the first interlayer film is within the specified range of the present invention from the viewpoint of easy film removal. Furthermore, No. As shown in FIGS. 9 and 10, it is understood that by forming the second intermediate film, both excellent adhesiveness and easy film removal can be achieved.

Example 3 In Example 3, the effect of the residual stress of the hard coating on the adhesion between the substrate and the hard coating was examined.

As in Example 1, a cathode discharge type arc ion plating device was used, and Ti--Cr--Al was used.
(10:18:72) using a target, the substrate temperature was changed within the range of 300 to 600 ° C. as shown in Table 3, and the other conditions were the same as in Example 1, and hard coatings with different residual stresses. (Each film thickness is about 3 μm) was formed on the substrate. High speed tool steel (JIS-SKH51
Chips made at tempering temperature: 550 ° C. were used.

Using a chip coated with a hard coating, a scratch test was conducted in the same manner as in Example 2 to evaluate the adhesion. Further, the film of the chip was partially scraped off to examine the hardness of the base material. Furthermore, the residual compressive stress of the formed hard film was measured by the above-mentioned X-ray diffraction method. For the measurement, the diffraction line of the (111) plane of TiCrAl nitride having a cubic rock salt structure was used, and the residual compressive stress of the hard coating was calculated using the following parameters. The results are shown in Table 3.

<Parameters for calculating residual stress of coating>Young's modulus of coating: 450 GPa Poisson's ratio of coating: 0.22 Standard Bragg angle: 37.6 °

[0104]

[Table 3]

Table 3 No. As shown in 2 to 6, if the film formation is performed with the substrate temperature within the specified range of the present invention, the residual compressive stress of the obtained hard film can be suppressed to 8 GPa or less, and the adhesion between the substrate and the hard film can be improved. It turns out that an excellent product can be obtained. On the other hand, No. In Nos. 7 and 8, since the base material temperature was higher than the tempering temperature of the base material, not only the residual compressive stress was large and the adhesion was poor, but also the hardness of the base material was lowered.

[Example 4] In Example 4, a cutting experiment was conducted using a drill or hob coated with the hard film or the intermediate film of the present invention.

A cathode discharge type arc ion plating apparatus similar to that in Example 1 was used to form a film. In addition, in the present example, in order to form the first intermediate film and the second intermediate film in addition to the hard film, a plurality of evaporation sources (targets) not shown in FIG. 2 were installed to form the film. That is, to form a hard film, Ti-Cr-Al (atomic ratio 10: 1
8:72) A target or a Ti—Al target (for forming a conventional hard film) is used, and T is used for forming the first intermediate film.
An i-Al target (using a target having a composition different from that used for hard film formation) or a Ti target was used, and a Ti target was used for forming the second intermediate film (metal film). The single-layer or multi-layer coating (total coating thickness: about 3 μm) shown in 1 was formed on the substrate. For the substrate, a high speed tool steel (JIS-SKH51 tempering temperature: 550 ° C.) drill (diameter 6 mm, 2 blades), a high speed tool steel (JIS-SKH51) hob (outer diameter 90
mm, blade length 90 mm, number of openings 3), and tips made of high speed tool steel were used. The substrate temperature during film formation was constant at 480 ° C.

Using a drill having a film formed thereon, a cutting test was conducted under the following conditions to examine the drill life. Further, using a hob having a film formed thereon, a cutting test was conducted under the following conditions to examine the degree of hob crater wear and to evaluate the wear resistance.
The results are shown in Table 4.

<Drill cutting test conditions> Workpiece material: S55C (non-heat treated material: HB220) Cutting speed: 60m / min Feed: 0.1 mm / revolution Hole depth: 12 mm Others: Dry cut, air blow only

<Hob cutting conditions> Work Material: SCM415 Cutting speed: 200m / min Axial feed: 3 mm / rotation Number of workpieces processed: 400 Evaluation: Crater wear

[0111]

[Table 4]

From Table 4, No. It can be seen that the coatings formed by Nos. 2 to 4 satisfy the requirements of the present invention, and thus have a long drill life, small hob crater wear, and good wear resistance when coated on a drill. On the other hand, No. No. 1 has a hard coating formed that does not satisfy the requirements of the present invention, and therefore it is understood that even if it is coated on a drill or a hob, it does not exhibit excellent wear resistance.

[Example 5] In Example 5, a solid lubricating film was formed on a hard film and a cutting test was conducted.

Using the apparatus shown in FIG. 3, Ti--Cr--Al
Target, Ti-V-Al target, Ti-Cr-
Using an Al-Si target or a Ti-Al target (for conventional film formation), a hard film (nitride film or carbonitride film: each having a composition shown in Table 5: a film thickness of about 3 μm
m) was formed on the substrate. A cemented carbide drill (diameter: 6 mm, two blades) and a cemented carbide tip (mirror finish) were used for the substrate.

The apparatus shown in FIG. 3 comprises a cathode discharge type arc ion plating apparatus for forming a hard film and a sputtering apparatus for forming a solid lubricating film. The film was formed using a cathode discharge type arc ion plating device.

The hard coating was formed as follows. That is, after introducing the substrate into the apparatus, the substrate temperature was set to 550 ° C., the degree of vacuum was set to 4 × 10 ⁻³ Pa or less, and then cleaning was performed using Ar ions (Ar pressure: 2 Pa, substrate voltage: 400 V). After the cleaning was completed, nitrogen was introduced so that the inside of the apparatus was about 3 Pa, the arc current was 100 A, and the substrate voltage was -150 V with respect to the earth potential to form a film.

Next, after cooling the substrate to about 200 ° C. in the apparatus, a hard coating is formed by using two sputtering evaporation sources (metal evaporation source: W or Cr and carbon evaporation source) provided in the same chamber. A solid lubricating film was formed on top.

The solid lubricating film was formed as follows.
First, using the metal evaporation source target 21, Ar gas pressure:
After forming a metal layer (Cr or W) of about 0.5 μm on the hard coating W under the conditions of 0.4 Pa, power: 500 W, and substrate bias: 50 V, the solid carbon target 22 is evaporated under the same Ar gas pressure. Then, by changing the electric power applied to the metal evaporation source 21 and the solid carbon source 22, a DLC (diamond-like carbon) film containing a metal element was formed. The substrate temperature at the time of forming the DLC film is about 200 ° C.,
The substrate bias was -150V with respect to the ground potential.

The compositions of the formed hard film and solid lubricating film were analyzed by Auger spectroscopy. The hardness of the hard film and the solid lubricating film was measured with a Vickers hardness meter (load: 0.
25N, holding time: 15 seconds). Further, a cutting test was performed under the following conditions using a drill having these coatings formed thereon.
The results are shown in Table 5.

<Drill cutting test> Work Material: S50C (Non-heat treated material) Cutting speed: 60m / min Feed: 0.1 mm / revolution Hole depth: 18 mm (hole depth / drill diameter = 3) Others: Dry cut, air blow only Life evaluation: Number of holes that can be drilled

[0121]

[Table 5]

From Table 5, in the case of only the conventional hard coating (N
o. The tool (No. 3 to 7) having the hard coating or the solid lubricating film of the present invention has a longer life than that of Nos. 1 and 2).
As shown in Nos. 8 to 11, it is preferable to form a solid lubricating film on the hard film of the present invention.

[Example 6] In Example 6, the effect of changing the composition of the solid lubricating film on the hardness, friction coefficient and cutting test results of the resulting film was examined.

Using a device similar to that of Example 5, Ti--Cr
Using an Al (atomic ratio 10:20:70) target, a hard coating (thickness of about 3 μm) is formed on a substrate made of a cemented carbide chip or a cemented carbide drill, and then,
As in Example 5, two sputtering evaporation sources (Cr or W) were used to form a solid lubricating film on the hard film in which the ratio of the metal component (Cr, W) and carbon was changed. The ratio of the metal component and carbon of the solid lubricating film was controlled by changing the electric power applied to each sputtering evaporation source. The other film forming conditions for the solid lubricating film are the same as in Example 5.

The compositions of the obtained hard coating and solid lubricating coating and the hardness of the hard coating and solid lubricating coating were measured in the same manner as in Example 5. In addition, when the target work material is an iron-based alloy, the friction coefficient of the composite coating (cutting film + solid lubricating film) with respect to the iron-based alloy was measured by the following sliding test using the chip on which the film was formed. .

<Sliding test conditions> Equipment: Reciprocating sliding ball-on-disk test equipment Target workpiece: S50C ball (non-heat treated material) Load: 1.96N Sliding speed: 2 cm / sec Sliding distance: 50m Evaluation: Friction coefficient when sliding 50 m

Then, a cutting test was conducted under the same conditions as in Example 5, using a drill having a film formed thereon. The results are shown in Table 6.

[0128]

[Table 6]

In Table 6, No. 1 to 3 and 8
No. 4 to 7, 9 and 10 have a higher hardness and a smaller wear coefficient of the solid lubricating film, and as a result, a longer life in the cutting test, as is clear from the above, the solid lubricating film defined in the present invention is applied on the hard film. It can be seen that by providing the solid lubricant film, the strength of the solid lubricating film can be secured and the life of the cutting tool can be extended.

[Embodiment 7] In Embodiment 7, the effect of the solid lubricating film specified in the present invention on the life of the drill was examined.

Using the same apparatus as in Example 5, Ti--Cr
Using an Al (atomic ratio 10:20:70) target, a hard coating (thickness of about 3 μm) is formed on a substrate made of a cemented carbide chip and a cemented carbide drill, and then,
Using two sputtering evaporation sources as in Example 5,
A solid lubricating film in which the ratio of metal components (Cr, W) and carbon was changed was formed on the hard film.

The composition of the obtained film was measured in the same manner as in Example 5. In addition, Table 7
The hole depth is changed as shown in FIG.
A cutting test was conducted in the same manner as in. The results are shown in Table 7.

[0133]

[Table 7]

From Table 7, when the hard film-coated tool of the present invention is used for cutting, it is preferable to provide a solid lubricating film from the viewpoint of prolonging the service life, and in particular, the hole depth / drill diameter exceeds twice. It can be seen that the solid lubricating film of the present invention sufficiently exerts its effect when cutting holes.

[0135]

As described above, by controlling the composition of the hard coating as in the present invention, it is possible to provide a tool which exhibits excellent wear resistance over a long period of time as compared with conventional cutting tools and the like. In addition, a hard coating tool that improves the adhesion between the base material and the hard coating by providing a specified intermediate film, and a specified solid lubricating film provides excellent sliding characteristics, making it possible to use iron-based alloys and aluminum. It has also become possible to provide a hard film-coated tool that enables long-term cutting in dry processing or semi-dry processing for materials that easily weld such as base alloys and titanium base alloys. The hard film-coated tool provided with the first intermediate film specified in the present invention is easy to remove the film portion, and is therefore suitable for a tool that is repeatedly used after removing the used film and re-coating.

[Brief description of drawings]

FIG. 1 is a metal component T in a (Ti, Al, Cr) N film.
The composition of i, Al and Cr shows the scope of the present invention.

FIG. 2 is a diagram schematically showing a film forming apparatus used in Example 1.

FIG. 3 is a diagram schematically showing a film forming apparatus used in Example 5.

[Explanation of symbols]

1 Container 2 Arc-type Evaporation Source 3 Support 4 Bias Power Supply 6 Arc Evaporation Source (Target) 7 Arc Power Supply 8 Magnet (Magnetic Field Forming Means) 11 Exhaust Port 12 Gas Supply Port W Object (Substrate, Substrate) 21 Sputtering Evaporation Source (Cr or W target) 22 sputtering evaporation source (solid carbon target) 23 sputtering power source

Continued front page    F-term (reference) 3C037 CC02 CC08 CC09                 3C046 FF03 FF05 FF10 FF16 FF21                 4K029 AA02 AA04 BA07 BA17 BA54                       BA55 BB02 BC02 BD05 CA04                       EA08

Claims (13)

[Claims] 1. The following composition 1 or composition 2 on a metal substrate.
A hard film-coated tool characterized in that at least one hard film satisfying the requirements of (1) is formed. <Composition _{1> (Ti 1-abcd Al} a Cr b Si c B d) (C
_1-e N _e ) 0.5 ≦ a ≦ 0.8, 0.06 ≦ b, 0 ≦ c ≦ 0.1, 0 ≦ d ≦ 0.1, 0 ≦ c + d ≦ 0.1, a + b + c + d <1, 0.5 ≦ e ≦ 1 (a, b, c and d represent atomic ratios of Al, Cr, Si and B, and e represents atomic ratio of N) <Composition 2> (Ti _a Al _b V _c ) (C _1-d N _d ) 0.02 ≦ a ≦ 0.3, 0.5 <b ≦ 0.8, 0.05 <c, 0.7 ≦ b + c, a + b + c = 1, 0.5 ≦ d ≦ 1 (a, b and c represent atomic ratios of Ti, Al and V, respectively, and d represents atomic ratio of N) 2. The hard coating tool according to claim 1, wherein at least one layer of a first intermediate film satisfying the following composition is formed between the metal base material and the hard coating. (Ti _1-x Al _x ) (C _1-y N _y ) 0 ≦ x ≦ 0.25, 0.5 ≦ y ≦ 1 (x represents the atomic ratio of Al and y represents the atomic ratio of N) 3. The hard coating according to claim 1, wherein at least one metal layer or alloy layer containing Ti and / or Cr is formed as a second intermediate film on the surface of the metal substrate in advance. tool. 4. The residual compressive stress of the hard coating is 8 GPa.
It is the following, The hard film coating tool in any one of Claims 1-3. 5. The solid lubricating film according to claim 1, wherein the outermost surface coating is a solid lubricating film having a wear coefficient smaller than that of the hard coating with respect to the work material. Hard coating tool. 6. The solid lubricating film comprises W, Cr, Ti, M
The hard film-coated tool according to claim 5, which contains 30 atomic% or less of at least one selected from the group consisting of o and the balance mainly comprises C. 7. The material to be processed is an iron-based alloy, an aluminum-based alloy, a titanium-based alloy or a copper-based alloy.
The hard film coated tool according to. 8. The hard coating tool according to claim 5, which is used for dry cutting or semi-dry cutting. 9. The hard coating tool according to claim 1, wherein the metal substrate is an iron-based alloy substrate. 10. The hard coating tool according to claim 9, wherein the iron-based alloy base material is an iron-based alloy base material that has been tempered at 500 ° C. or higher. 11. The hard coating tool according to claim 5, wherein the metal base material is a cemented carbide base material. 12. The hard coating tool according to claim 1, which is a hob, a drill or an end mill. 13. A method for producing a hard coating tool according to claim 9 or 10, wherein the arc ion plating method is adopted and the iron-based alloy base material is maintained at 350 ° C. to 520 ° C. A method for producing a hard coating tool, which comprises forming a hard coating.