JP3337884B2 - Multilayer coating member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a member coated with a multilayer film having excellent wear, oxidation and thermal shock resistances by covering a metallic member with a coating member comprising a film of double carbide of Ti and Al held between films of Ti carbides or the like. SOLUTION: A base body consisting of a metallic member (such as stainless steel), a sintered alloy (such as cemented carbide) or a ceramic sintered body (such as Al2 O3 sintered body) is covered with a coating member, which consists of a single layer film of one kind or a composite layer film of two or more kinds selected from double carbide, nitride, carbonitride, carbide oxide, or nitride oxide of Ti and Al [such as (TiAl)C] held between single layers of one kind or composite layers of two or more kinds selected from carbide, nitride, carbonitride, carbide oxide, nitride oxide, or carbide nitride oxide of Ti (such as TiC). The total film thickness is controlled to 0.5-15mm, while the upper and the lower layer are controlled to 0.1-3mm each. Thereby, the obtd. member coated with a multilayer film has excellent resistance against chipping, melt sticking and peeling.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer film-coated member in which a metal, alloy or ceramic sintered body is coated with at least three layers including a layer made of a compound of Ti and Al on a substrate. Specifically, a high-hardness, high-toughness multi-layer coating is coated on a metal, alloy or ceramic sintered body base, for example, a cutting tool represented by a turning tool, a milling tool, a drill, an end mill, a slitter, or the like. The present invention relates to a multilayer film-coated member which is optimal as a wear-resistant tool represented by a cutting tool such as a cutting blade, a cutting blade, a die, and a nozzle.

[0002]

2. Description of the Related Art Metal, alloy and ceramic substrates are coated with a ceramic coating having a thickness of 20 μm or less,
Numerous coating members have been proposed in order to effectively draw out the characteristics of the base and the coating to achieve a long life. The method of coating the coating on the coating member is roughly classified into a chemical vapor deposition method (CVD method) and a physical vapor deposition method (PVD method). Among them, a film coated by the PVD method has an advantage of increasing abrasion resistance without deteriorating the strength of the substrate. For this reason, coatings of coated cutting tools typified by drills, end mills, and throw-away inserts for milling, which generally emphasize strength and fracture resistance, are currently coated by a PVD method.

[0003] It is well known that a titanium nitride film is applied to improve wear resistance. However, metal nitrides typified by titanium nitride are liable to be oxidized at high temperatures, and have a problem that wear resistance is significantly deteriorated. In order to improve the problem of oxidation of the titanium nitride film, one proposed in the mid-1980s was TiOA.
There is a 1N coating. A representative example of a coating member coated with this TiAlN coating is disclosed in Japanese Patent Application Laid-Open No. Sho 62-56565.

[0004]

Japanese Patent Application Laid-Open No. 62-56565 as a prior art relating to a coating of a TiAl compound discloses that one of a carbide, a nitride and a carbonitride of Ti and Al is formed on the surface of a substrate. A surface-coated hard member having excellent wear resistance in which a hard coating layer composed of a single layer or two or more layers is formed with a thickness of 0.5 to 10 μm.

[0005] The surface-coated hard member described in the publication is a coated hard member having improved oxidation resistance and abrasion resistance as compared with the Ti compound coating as in the beginning of development, but has a degraded mechanical property. However, there is a problem that the cutting performance is reduced when applied to a tool, especially a cutting tool used under severe conditions. In other words, the surface-coated hard member described in the publication is
By including Al in the coating, the chemical properties of the coating surface have been improved as compared with the coating of the Ti compound, but the fracture toughness value is lowered. There is a problem that the life of the coating is shortened due to oxidation of the coating, rapid progress of wear, deterioration due to thermal shock resistance, and welding to the work material.

The present invention has solved the above-mentioned problems. Specifically, in a wide range from a low-temperature region to a high-temperature region, the present invention has abrasion resistance, oxidation resistance, thermal shock resistance, and thermal shock resistance. It is an object of the present invention to provide a multilayer-coated member that is more excellent in chipping property, welding resistance, and peeling resistance of a coating film.

[0007]

Means for Solving the Problems The present inventors have found that a coated member in which a coating of a compound of Ti and Al is coated on a cemented carbide substrate exhibits an excellent effect when used in a low temperature range. On the other hand, while studying the problem that the effect is reduced when used in a high-temperature region, if a small amount of oxygen element is contained in the film of the compound of Ti and Al, the temperature ranges from low to high temperatures. It has been found that abrasion resistance is not reduced and the life is improved, and based on this, one of the present inventors has proposed as Japanese Patent Application No. 6-180908.

After that, the present inventors have studied a film containing a small amount of oxygen element in a film of a compound of Ti and Al in consideration of another direction. In order to make the most of the film of the compound of Ti and Al having the characteristics described above, the composition of the film including this film has a very large effect, and in particular, the film of the compound of Ti and Al is applied to the outermost surface. The inventors have found that the effect can be further exerted when the film is sandwiched by a film of a Ti compound without forming the film, thereby completing the present invention.

That is, the multilayer film-coated member of the present invention is a coated member in which a coating is coated on a base made of a metal member, a sintered alloy or a ceramic sintered body.
At least a first coating and a second coating are coated, and the first coating is made of a carbide, nitride, carbonitride, carbonate, or oxide of Ti.
A first layer composed of one type of a single layer or a composite layer of two or more types of a nitric oxide and a carbonitride; A composite layer containing a second layer composed of a composite carbonitride and a third layer composed of a composite nitride of Ti-Al, wherein the second coating is a laminate sandwiched by the first coating; It is characterized by the following.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The substrate in the multilayer film-coated member of the present invention is made of a metal member, a sintered alloy or a ceramic sintered body that can withstand the heating temperature when coating the multilayer film. Are metal members represented by, for example, stainless steel, heat-resistant alloys, high-speed steels, die steels, Ti alloys, Al alloys, cemented carbides, cermets, sintered alloys of powdered high-speed steel, and Al ₂ O ₃ based sintering. Ceramic sintered body such as a sintered body, a Si ₃ N ₄ based sintered body, a sialon based sintered body, and a ZrO ₂ based sintered body. Among these, when used as a cutting tool or a wear-resistant tool, a substrate made of a cemented carbide, a nitrogen-containing TiC-based cermet or a ceramic sintered body is preferable.

The coating on the substrate has a laminated structure in which at least a first coating and a second coating are covered, and the second coating is sandwiched between the first coatings. Then, the first coating, the second coating, and the first coating are formed of at least three coatings in that order on the substrate.

Of these coatings, the first coating is, for example, TiC, TiN, TiCN, TiCO, T
It is a single layer or a composite layer of two or more of iNO and TiCNO. Further, the second coating is, for example, (TiAl) C, (TiAl) N, (TiA
l) CN, (TiAl) CO, (TiAl) NO, (T
iAl) A single layer or a composite layer of two or more layers of CNO. Of these, the second coating will be described in detail. For example, the TiAlN coating is made of Ti in TiN.
The atoms are replaced by Al atoms at a certain ratio, and if the concentration exceeds a certain concentration, AlN will precipitate. In this case, the mechanical properties of the coating are significantly reduced. When the TiAlN film is exposed to an oxidizing atmosphere at a high temperature, the solid solution of Al is oxidized near the surface to form an aluminum oxide film, which serves as a protective film. For this purpose, the second coating made of a TiAl compound has an Al concentration of 30% or more and Al and T
It is preferable that the total concentration of i and the metal element is 50% or more.

The layered structure in which the second coating is sandwiched by the first coating means that the lower layer made of the first coating formed between the base and the second coating is formed on the surface opposite to the second coating. When there is an upper layer made of the first coating, and the lower layer and the upper layer each have symmetry including the same element with respect to the second coating, specifically, for example, the substrate -TiC ( Underlayer)
-Second coating-TiC (upper layer), substrate-TiN (lower layer)-
Second film-TiN (upper layer), substrate-TiCN (lower layer)-
Second film-TiCN (upper layer), substrate-TiN (lower layer)-
TiNC (lower layer)-second coating-TiN (upper layer)-TiN
A combination of C (upper layer) can be given. Further, when the lower layer and the upper layer have the same thickness with the second coating as the center, specifically, for example, the base is -0.5 μm
Film thickness (lower layer)-second film-0.5 µm film thickness (upper layer), substrate-1.5 µm film thickness (lower layer)-second film-
A combination of 1.5 μm film thickness (upper layer), substrate-3.0 μm film thickness (lower layer) -second coating-3.0 μm film thickness (upper layer) can be given. Further, the lower layer and the upper layer are made of the same element with the second coating as the center,
In addition, a combination having the same film thickness is excellent in balance and is particularly preferable. With such a coating configuration, compressive stress remains in the coating, particularly on the coating surface, and stress is relaxed at the interface between the substrate and the coating, thereby improving the peeling resistance of the coating and the fracture resistance of the coating member. Which is preferable.

More specifically, a more preferred configuration of the laminate in which the second coating is sandwiched by the first coating is as follows. The first coating is made of Ti nitride, and the second coating is made of Ti-Al composite carbonitride. (TiAlCNO), a second layer made of Ti-Al composite carbonitride (TiAlCN), and Ti-A
1) and a third layer made of a composite nitride (TiAlN), and the first layer is laminated so as to have a symmetry sandwiched between the second layer and the third layer. It is even more preferred. To express this in another way, the substrate-TiN layer (first coating) -TiAlN layer (third layer) -TiAlCN layer (second layer) -TiAlCN
O layer (first layer) -TiAlCN layer (second layer) -TiAl
N layer (third layer)-TiN layer (first coating)
That is, they are sequentially laminated on the base.

Further, a more preferable structure of the lamination will be described in detail. The first film is made of Ti nitride, and the second film is made of Ti.
Composite carbonitride with Ti-Al coating (TiAlCNO)
Carbon nitride (TiAlC) composed of a first layer of Ti and Al
N) and a composite nitride of Ti-Al (TiAl)
N) is a composite layer composed of a third layer and a first layer having a symmetry sandwiched by a second layer and a third layer in a sequential manner as described above. Is represented by TiaAlbCxNyOz.
i-Al composite carbonitride, the second layer of which is TiaAl
bCsNt is made of a complex carbonitride of Ti—Al represented by the formula of CCSNt, and the third layer is made of Ti—A represented by the formula of TiaAlbN.
1 of the composite nitride. [However, in each formula, Ti is titanium, Al is aluminum, C is carbon, N
Represents nitrogen, O represents oxygen, a and b represent the respective atomic ratios of metal elements Ti and Al, and x, y and z represent the respective atomic ratios of non-metallic elements C, N and O. And s and t represent the respective atomic ratios of the nonmetallic elements C and N, and a + b = 1, 0.95 ≧ a ≧ 0.
05, x + y + z = 1, 0.89 ≧ x ≧ 0.1, 0.8
9 ≧ y ≧ 0.1, 0.25 ≧ z ≧ 0.01, 0.9 ≧ s
≧ 0.1, 0.9 ≧ t ≧ 0.1]

The coating of the multi-layer coating member of the present invention described above can have various configurations. Specifically, for example, depending on the material of the base, it is preferable to coat a base layer made of a metal or an alloy between the base and the coating in order to enhance the adhesion between the base and the coating. As the underlayer, specifically, for example, Ti, Zr,
W, Mo, Ta, Nb metal or TiAl, Ti ₃ A
1, an alloy made of an intermetallic compound of TiAl ₃ . Among these, it is preferable that the underlayer is made of Ti or an alloy containing Ti. The thickness of the underlayer may be a thickness that enhances the adhesion between the substrate and the coating, and specifically,
For example, it is 0.05 to 2 μm, preferably 0.1 to 1 μm.

The thickness of the coating in the multi-layer coating member of the present invention can be determined by considering the impact resistance and fracture resistance, specifically, for example, in a heavy cutting area or a milling cutting tool to which a high load is applied, and a drill. Edge shears such as
When it is used for a simple cutting tool, it may be formed as thin as possible, and may be formed slightly thicker in applications where wear resistance is important.
The specific coating thickness is the total coating thickness of the total of the first coating and the second coating, that is, the total coating thickness is 0.5 to 15 μm,
Preferably, the thickness is 1 to 9 μm and the thickness of the first coating is 0.1 μm.
-3 μm, preferably 0.2-2 μm, and the thickness of the second coating is 0.4-12 μm, preferably 0.8-7 μm
And the thickness of the first layer in the second coating is 0.2 to 5 μm.
m, preferably 0.4 to 3 μm, the thickness of the second layer is 0.1 to 4 μm, preferably 0.2 to 2 μm, and the thickness of the third layer is 0.1 to 3 μm, preferably 0.2-2μ
m.

The multilayer film-coated member of the present invention is a metal member represented by stainless steel, a heat-resistant alloy, a high-speed steel, a die steel, a Ti alloy, an Al alloy, a cemented carbide, a cermet, which are conventionally commercially available. , Sintered alloy of powdered high-speed steel, Al ₂ O ₃ based sintered body, Si ₃ N ₄ based sintered body, Sialon based sintered body, ZrO
A cemented carbide equivalent to P20 to P40, M20 to 40 and K10 to K20, which is based on a ceramic sintered body of the ₂ series sintered body and is preferably classified in the selection criteria for the use of cemented carbide according to JIS B4053 Material, particularly preferably P
A substrate made of a cemented carbide material equivalent to 30, M20 or M30 may be used. The surface of the substrate is polished if necessary, and is subjected to a cleaning process using ultrasonic waves, an organic solvent, or the like.
It can be manufactured by coating a film on a substrate by a conventional physical vapor deposition method (PVD method), chemical vapor deposition method (CVD method) or plasma CVD method.

When a film is coated on a substrate, a PVD method, a CVD method, or a plasma CVD method can be used depending on the quality of each film, including a base layer to be coated if necessary. Among these, it is preferable to perform all coatings from the manufacturing process by a PVD method typified by an ion plating method or a sputtering method. Among them, coating treatment is preferably performed by an ion plating method, particularly an arc ion plating method. Is preferred.

The case where the coating in the multilayer coating member of the present invention is produced by the ion plating method will be described in more detail. The metal source is made of titanium, metal aluminum and the metal to be added independently. Or an alloy containing the respective elements may be used. The method of ionizing the metal may be arc discharge, glow discharge, high-frequency heating, or the like. As a gas used in the ion plating method, a compound gas such as ammonia containing nitrogen may be used in addition to a gas for generating nitride, that is, a nitrogen gas. It is preferable to introduce this reaction gas into a furnace, ionize a metal or alloy as a metal source, and apply a negative bias to the substrate to synthesize a coating.

[0021]

The multilayer film-coated member of the present invention has a film structure in which the second film is sandwiched by the first film, and in particular, the second film is formed by a titanium / aluminum carbonitride film as a core. By forming a film, an action of causing a large compressive stress to remain in the coating occurs, and an action of relaxing the stress in the vicinity of the interface between the substrate and the coating occurs. As a result, the strength, abrasion resistance and resistance of the coating are obtained. It is a function of improving the deficiency.

Commercially available shape SNGN 120408
A substrate made of cemented carbide (material equivalent to JIS standard P30). After cleaning the surface of the substrate with an organic solvent, the substrate is installed in a chamber of an arc discharge plasma device. installation with), the inside of the chamber was set to 1.0 × 10 ^over 6 to 3.0 × 10 ^over 6 Torr vacuum. Next, the inside of the chamber was maintained at the gas composition and gas pressure shown in Tables 1-1, 1-2 and 1-3, and the substrate was heated to about 450 ° C. First, the substrate was coated with Ti ions for 2 minutes (underlayer). Next, the arc discharge current was maintained at about 100 A, and the Ti-Al alloy was added in Tables 1-1 and 1-2.
Under the respective conditions shown in Tables 1-3, the first coating and the second coating were coated in the order from the top to the bottom of the table to obtain products 1 to 5 of the present invention and comparative products 1 to 3.
(A bias voltage of -800 V was applied to the substrate when the underlayer was coated, and a bias voltage of -100 V was applied to the substrate when coating other films.)

The film thickness of each of the underlayer, the first coating, and the second coating of the products 1 to 5 of the present invention and the comparative products 1 to 3 was
Investigated with a high-resolution scanning electron microscope
The results are shown in Table 1-1, Table 1-2 and Table 1-3. Work material: S45C using inventive products 1 to 5 and comparative products 1 to 3
(HB190), cutting speed: 300 m / min, feed:
0.5 mm / rev, depth of cut: 2.0 mm, cutting time:
Dry cutting test conditions for 60 min (described as "first cutting strip" in Table 2), work material: S48C, cutting speed: 15
0 m / min, feed: 0.3 mm / rev, depth of cut:
Under a dry cutting test condition (1.5 mm, cutting time: 30 min) (described in Table 2 as “second cutting condition”), a cutting test was performed to determine an average flank wear width, and the results are shown in Table 2. .

[0024]

[Table 1-1]

[0025]

[Table 1-2]

[0026]

[Table 1-3]

[0027]

[Table 2]

[0028]

Example 2 A commercially available cemented carbide end mill (equivalent to JIS standard M20) was used as a substrate, and only the first layer of the second coating was thinned by 0.2 μm using this substrate. The products of the present invention 6 to 10 under the same coating conditions as in Example 1.
I got Except that the substrate was the same as the products 6 to 10 of the present invention,
Comparative products 4 to 6 were obtained under the same coating conditions as Comparative products 1 to 3 obtained in Example 1. Using the inventive products 6 to 10 and comparative products 4 to 6 thus obtained, a work material: SKD61 (HRC4
1), feed: 0.08 / rev, depth of cut: Ad = 12m
m, Rd = 0.8 mm, cutting speed: 20 m / min, tool shape: water-soluble cutting test consisting of cutting conditions of a 2-flute end mill with a diameter of 8 mm (described in Table 3 as “third cutting condition”)
And work material: SUS304 (HB180), feed: 0.
03 / rev, depth of cut: Ad = 7 mm, Rd = 1 mm,
Water-soluble cutting test under cutting conditions of cutting speed: 50 m / min, tool shape: 2-flute end mill with 5 mm diameter (Table 3)
Was described as “fourth cutting condition”, and the flank wear width at a cutting length of 50 m was examined. The results are shown in Table 3.

[0029]

[Table 3]

[0030]

The multilayer coating member of the present invention comprises titanium / aluminum carbonitride, titanium / aluminum carbonitride,
Or, compared to conventional coated members coated with a coating of titanium / aluminum nitride, abrasion resistance, oxidation resistance, thermal shock resistance, fracture resistance, The welding property and the peeling resistance of the coating film are more excellent, and the remarkable effect is exhibited particularly in a high temperature region, and as a result, there is an excellent effect that the life is extended in a wide range from a low temperature region to a high temperature region.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Mamoru Kohata 580 Horikawa-cho, Saiwai-ku, Kawasaki-shi, Kanagawa Solid Square Toshiba Tungaloy Co., Ltd. In-house (56) References JP-A-4-201002 (JP, A) JP-A-4-201003 (JP, A) JP-A-6-136514 (JP, A) JP-A-6-170610 (JP, A) JP-A-7-108404 (JP, A) JP-A-3-120352 (JP) JP-A-5-69205 (JP, A) JP-A-5-337703 (JP, A) JP-A-6-346226 (JP, A) JP-A-7-243024 (JP, A) 8-168904 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C23C 14/00-14/58 C23C 16/00-16/56 C23C 28/04 B23B 27/14

Claims (5)

(57) [Claims] 1. A coating member comprising a substrate made of a metal member, a sintered alloy or a ceramic sintered body coated with a coating, wherein the coating is coated with at least a first coating and a second coating. The first film is a single layer or a composite layer of two or more of carbides, nitrides, carbonitrides, carbonates, nitrides and carbonitrides of Ti, and the second film is Ti A composite layer containing a first layer composed of a composite carbonitride of -Al, a second layer composed of a composite carbonitride of Ti-Al, and a third layer composed of a composite nitride of Ti-Al; The second coating is the first
A multilayer film-coated member, wherein the member is a laminate sandwiched between films. 2. The second coating according to claim 1, wherein the first layer comprises the second layer.
The multi-layer film-coated member according to claim 1, wherein the member is a symmetrical laminate sandwiched between a layer and the third layer, and the total of the coatings is at least seven layers. 3. The method according to claim 1, wherein the first layer has the following formula (A), the second layer has the following formula (B), and the third layer has the following formula (C). The multilayer-coated member according to claim 1 or 2, wherein _{Ti a Al b C x N y} O z ------ (A) Ti a Al b C s N t -------- (B) Ti a Al b N ------- --- (C) {where, Ti in each of the formulas (A), (B) and (C)
Is titanium, Al is aluminum, C is carbon, N is nitrogen,
O represents oxygen, and a and b are metal elements Ti and A
1 represents the atomic ratio of each, x, y, and z represent the atomic ratios of the nonmetallic elements C, N, and O, and s and t represent the atomic ratios of the nonmetallic elements, C and N. A + b = 1, 0.95 ≧ a ≧ 0.05, x + y +
z = 1, 0.89 ≧ x ≧ 0.1, 0.89 ≧ y ≧ 0.
1, 0.25 ≧ z ≧ 0.01, 0.9 ≧ s ≧ 0.1,
0.9 ≧ t ≧ 0.1. 4. The multilayer film-coated member according to claim 1, wherein an underlayer made of a metal or an alloy is coated between the substrate and the film. 5. The coating according to claim 1, wherein the total thickness is 0.5 to 15 μm.
5. The multilayer film-coated member according to claim 1, wherein the first film has a thickness of 0.1 to 3 μm.