JP2021119026A - Hard coating film-coated tool and manufacturing method thereof - Google Patents

Abstract

To provide a hard coating film-coated tool excellent in heat resistance and chipping resistance and to provide a manufacturing method of the hard coating film-coated tool.SOLUTION: A hard coating film-coated tool is made by forming titanium nitride aluminum coating film onto a base body according to chemical deposition method, and has a cutting edge, a rake face and a flank. There is a thinnest portion of the titanium nitride aluminum coating film on the cutting edge, of the cutting edge, the rake face and the flank, the titanium nitride aluminum coating film on the cutting edge has a composition rich in Ti and the titanium nitride aluminum coating film has a composition rich in Al on a portion of the rake face and the flank each separated by at least 1000 μm from the thinnest portion of the titanium nitride aluminum coating film on the cutting edge.SELECTED DRAWING: Figure 5

Description

The present invention relates to a tool coated with a titanium nitride aluminum hard film having excellent heat resistance and fracture resistance, and a method for manufacturing the same.

Conventionally, a cutting tool in which a hard film such as TiAlN, TiC, TiN, Ti (CN) is coated in a single layer or multiple layers has been used for cutting mild steel and the like. However, under increasingly severe cutting conditions, the cutting edge temperature of the cutting tool rises significantly during cutting. In the blade portion where the temperature is high, the crystal structure of the hard film is changed and the hardness is lowered, and the crater wear on the rake face and the wear on the flank surface progress, and there is a problem that the life is shortened. _{Therefore, a hard film using an Al 2} O ₃ film with excellent heat resistance has been proposed, but the fracture resistance is not sufficient under high-speed cutting conditions. In order to solve such a problem, a cutting tool having a hard film having excellent heat resistance and fracture resistance is desired.

Patent No. 3277558 (Patent Document 1) states that when a wear-resistant TiAlN film is formed on the surface of a substrate by a plasma CVD method, the discharge energy intensity of plasma on the rake face side is made stronger than that on the flank side. A method for manufacturing a coated cutting tip in which the atomic ratio of Al to Ti in the film (C _Al / C _Ti ) is 1.5 to 9.0 on the rake face and 0.6 to 1.4 on the flank surface is disclosed. However, Patent Document 1 describes a technique for improving heat resistance and fracture resistance by making the composition of the TiAlN film coated on the cutting edge Ti-rich and the composition of the TiAlN film coated on the rake face and flank surface Al-rich. The idea was not recognized, and it was not possible to obtain a coated cutting tip with sufficient fracture resistance and heat resistance under high-speed cutting conditions.

Patent No. 3006453 (Patent Document 2), the surface of the cemented carbide substrate has a multilayer ceramic film containing Al ₂ O ₃ film, Al ₂ O part or the whole of the area of friction occurs between the workpiece _{Disclosed is a coated hard alloy tool in which several layers including three} films are removed and the film mainly composed of TiN or TiCN is exposed. However, it was found that the heat resistance was not sufficient and the tool life was short when used for high-speed cutting.

Patent No. 5800571 (Patent Document 3) states that Ti _a M _1-a (C _1-x N _x ) (where M is the 4th, 5th and 6th groups of the periodic table excluding Ti) on the surface of the substrate. A layer having a composition of 0.3 ≤ a ≤ 0.9, 0 ≤ x ≤ 1), which is at least one selected from the metals, Al, Si and Y, and Al _{b M'1-b} (C _1-y). N _y ) (However, M'is the composition of at least one selected from the metals of the 4th, 5th and 6th groups of the periodic table, Si and Y, 0.4 ≤ b ≤ 0.9, 0 ≤ y ≤ 1). The B layer (the ratio of Al to the total amount of Ti and Al is higher than that of the A layer) is alternately and repeatedly laminated to form a coating layer, and the thickness of the A layer and the B layer in the coating layer at the cutting edge is increased. We disclose a cutting tool in which the ratio (t _cA / t _cB ) is larger than the ratio of the thickness of the A layer to the B layer of the coating layer on the rake face (t _rA / t _rB). However, it was found that since the A layer and the B layer have a difference in thermal expansion coefficient due to the composition difference, delamination occurs during high-speed cutting and the life is short.

Japanese Patent No. 3277558 Japanese Patent No. 3006453 Japanese Patent No. 5800571

Therefore, an object of the present invention is a case where a titanium aluminum nitride film is formed by a chemical vapor deposition method and used for high-speed cutting by optimizing each composition of the titanium nitride aluminum film on the cutting edge portion, the rake face and the flank surface. Even so, it is an object of the present invention to provide a hard film coating tool having a titanium nitride aluminum film excellent in heat resistance and fracture resistance, and a method for producing the same.

The hard film coating tool of the present invention is formed by forming a titanium nitride aluminum film on a substrate, and has a cutting edge portion, a rake surface, and a flank surface.
The titanium nitride aluminum film is a chemical vapor deposition film.
Of the cutting edge portion, the rake face, and the flank surface, the cutting edge portion has the thinnest portion of the titanium nitride aluminum film, and the titanium nitride aluminum film on the cutting edge portion is (Tix ₁ Aly ₁ ) Nz. ₁ (However, x ₁ , y ₁ and z ₁ are atomic ratios, respectively, and are numbers that satisfy _{0.26 ≤ x 1} ≤ 0.4, 0.1 ≤ y ₁ ≤ 0.24, and x ₁ + y ₁ + z _{1 = 1.)} Has a Ti-rich composition represented
At the rake face and the flank, respectively, at least 1000 μm away from the thinnest portion of the titanium nitride aluminum film on the cutting edge, the titanium nitride aluminum film is (Tix ₂ Aly ₂ ) Nz ₂ (where x _2). , Y ₂ and z ₂ are atomic ratios, respectively, and are Al-rich numbers that satisfy _{0.06 ≤ x 2} ≤ 0.23, 0.25 ≤ y ₂ ≤ 0.45, and x ₂ + y ₂ + z _{2 = 1.} It is characterized by having a composition.

x ₁ and y ₁ satisfy the atomic ratios of 0.28 ≤ x ₁ ≤ 0.40 and 0.10 ≤ y _{1 ≤ 0.2 2 , respectively, and x 2} and y 2 satisfy the atomic ratios of 0.08 ≤ x ₂ ≤ 0.22 and 0.26 ≤ y ₂ ≤, respectively. It is preferable that 0.43 is satisfied, _{the difference between x 1} and x ₂ is 0.10 or more, and the difference between y ₂ and y ₁ is 0.10 or more.

The region of the titanium nitride aluminum film on the rake face and the flank surface adjacent to the cutting edge portion preferably has a Ti-rich composition.

The titanium nitride aluminum film preferably has a columnar crystal structure as a main component.

The region of the titanium aluminum nitride film on the rake face having a Ti-rich composition is 180 to 600 μm from the boundary between the cutting edge portion and the rake face and from the thinnest portion of the titanium nitride aluminum film on the cutting edge portion. A region existing in a range up to a distant position and having a Ti-rich composition of the titanium nitride aluminum film on the flank surface is formed from the boundary between the cutting edge portion and the flank surface to the cutting edge portion. It is preferably present in the range of 160 μm to 550 μm away from the thinnest portion of the titanium nitride aluminum film.

In the hard coating tool of the present invention, it is preferable that z ₁ satisfies the atomic ratio of 0.64 to 0.36 and z ₂ satisfies the atomic ratio of 0.69 to 0.32.

The hard film coating tool of the present invention has a base layer between the substrate and the titanium aluminum nitride film, and the base layer is a single-layer film composed of at least one of titanium carbonitride, titanium nitride, and titanium nitride zirconium. Alternatively, it is preferably a laminated film and has an fcc structure.

The method of the present invention for producing the above-mentioned hard film coating tool by a chemical vapor deposition method is 0.1 to 0.8% by volume, where the total of _{TiCl 4} gas, AlCl ₃ gas, NH ₃ gas, N ₂ gas and H _{2 gas is 100% by volume.} TiCl ₄ gas, 0.4 to 1.2% by volume AlCl ₃ gas, 4.0 to 23.5% by volume N ₂ gas, and the balance H ₂ gas, and the volume ratio of TiCl _{4 gas to AlCl 3 gas (TiCl 4} / AlCl _3). ) Is 0.3 to 0.7, and 0.7 to 1.9% by volume of NH ₃ gas, 3 to 16.5% by volume of N ₂ gas, and the remaining H ₂ gas are mixed gas B. This is characterized by forming the titanium nitride aluminum film.

In the manufacturing method of the present invention, a chemical vapor deposition apparatus including first and second pipes that rotate about a rotation axis O is used, and the first pipe has a first nozzle and the second pipe. The pipe has a second nozzle, and the distance H ₁ between the spout of the first nozzle and the rotating shaft O is made longer than _{the distance H 2 between the spout of the second nozzle and the rotating shaft O.} It is preferable that the mixed gas A is ejected from the first nozzle and the mixed gas B is ejected from the second nozzle.

Further, in the manufacturing method of the present invention, a chemical vapor deposition apparatus including first and second pipes that rotate about a rotation axis O is used, and the first pipe has a first nozzle and the second pipe. The pipe has a second nozzle, and the distance H ₁ between the spout of the first nozzle and the rotating shaft O is longer than _{the distance H 2 between the spout of the second nozzle and the rotating shaft O.} Then, it is preferable that the mixed gas A is ejected from the second nozzle and the mixed gas B is ejected from the first nozzle.

The chemical vapor deposition apparatus is provided around the first and second pipes between a plurality of shelves for placing the substrate and adjacent shelves, respectively, in order to block the flow of the raw material gas. The first and second nozzles are provided between each shelf and the partition plate located above the partition plate and at the upper part of the uppermost shelf, respectively, and the substrate in the shelf is provided. It is preferable that at least one through hole is provided around the hole, so that the raw material gas ejected from the first and second nozzles passes through the through hole.

The ratio of the distance H ₁ to the distance H _{2 (H 1} / H ₂ ) is preferably in the range of 1.5 to 3.

In the production method of the present invention, it is preferable to use a film formation pressure of 3 to 6 kPa and a film formation temperature of 750 to 830 ° C.

In the hard film coating tool of the present invention, the thinnest part of the titanium nitride aluminum film on the cutting edge is (Tix ₁ Aly ₁ ) Nz ₁ (however, x ₁ , y ₁ and z ₁ are atomic ratios, respectively, and 0.26 ≤ It _{has a Ti-rich composition represented by x 1} ≤ 0.4, 0.1 ≤ y ₁ ≤ 0.24, and x ₁ + y ₁ + z ₁ = 1), and is a titanium nitride aluminum film on the rake face and flank surface. However, at a portion at least 1000 μm away from the thinnest portion, (Tix ₂ Aly ₂ ) Nz ₂ (where x ₂ , y ₂ and z ₂ are atomic ratios, respectively, 0.06 ≤ x ₂ ≤ 0.23, 0.25 ≤ y. _It has an Al-rich composition represented by 2 ≤ 0.45 and x ₂ + y ₂ + z ₂ = 1 (that is, the titanium nitride aluminum film is Ti-rich at least at the cutting edge, and the above-mentioned Since the rake face and flank surface that are not affected by the cutting edge are Al-rich), the cutting edge that receives a strong impact during high-speed cutting not only has excellent chipping resistance (chipping resistance), but also has excellent chipping resistance. The Al-rich parts of the rake face and flank surface have excellent heat resistance, and the tool life is long even under high-speed cutting conditions.

It is the schematic which shows the cutting edge part, rake surface and flank surface of a hard film coating tool, and the base cutting edge part, the base rake surface and the base flank surface of the substrate. It is a schematic diagram which shows the vertical cross section of an example of the cutting edge part of a hard film coating tool. It is a schematic diagram which shows the vertical cross section of another example of the cutting edge part of a hard film coating tool. It is a perspective view which shows typically the substrate of the insert which is an example of the hard film coating tool of this invention. It is a schematic diagram which shows an example of the Ti-rich part and the Al-rich part in the titanium nitride aluminum film formed on the insert substrate of FIG. FIG. 6 is a schematic view partially showing a vertical cross section of the titanium nitride aluminum-coated insert of FIG. 4 (a). It is a scanning electron microscope (SEM) photograph (magnification 500 times) which shows the vertical cross section of the cutting edge part of the hard film coating tool of Example 1. It is an SEM photograph (magnification 5,000 times) which shows the vertical cross section near the _{position P 1} in the cutting edge part of the hard film coating tool of Example 1 shown in FIG. It is an SEM photograph (magnification 5,000 times) which shows the vertical cross section near the _{position P 2} of the rake face of the hard film covering tool of Example 1. FIG. It is an SEM photograph (magnification 5,000 times) which shows the vertical cross section near the _{position P 3 of the} flank surface of the hard film covering tool of Example 1. FIG. It is a schematic diagram which shows the measurement position of the composition and the film thickness in the vertical cross section of the cutting edge part of the hard film coating tool of Example 1. FIG. It is a schematic diagram which shows an example of the chemical vapor deposition apparatus (CVD furnace) which can be used for forming a titanium nitride aluminum film. It is a cross-sectional view which shows an example (the first pipe assembly) of a pipe assembly in a CVD furnace. It is sectional drawing which shows another example (the second pipe assembly) of the pipe assembly in a CVD furnace. It is a cross-sectional view which shows still another example (third pipe assembly) of a pipe assembly in a CVD furnace. It is a top view which shows an example of the substrate placing shelf in a CVD furnace. It is a partial vertical sectional view which shows the CVD furnace provided with the shelf of FIG. It is a schematic diagram which shows the gas flow path in the CVD furnace of FIG. It is a top view which shows another example of the substrate placing shelf in a CVD furnace. It is a partial cross-sectional schematic diagram which shows an example of the cutting edge exchange type rotary tool which attached the insert. It is a schematic diagram which shows the conventional CVD furnace. It is a cross-sectional view which shows the pipe used for the CVD furnace of FIG. It is a graph which shows the distribution of the atomic ratio of Ti and Al in the titanium aluminum nitride film on the rake face side of the hard film coating tool of Example 1. It is a graph which shows the distribution of the atomic ratio of Ti and Al in the titanium nitride aluminum film on the flank side of the hard film coating tool of Example 1. FIG. It is an SEM photograph (magnification 500 times) which shows the vertical cross section of the cutting edge part of the hard film coating tool of the prior art example 1.

[1] Hard film coating tool In the hard film coating tool of the present invention, a titanium aluminum nitride film is formed by a chemical vapor deposition method, and the thinnest part of the titanium aluminum nitride film on the cutting edge is (Tix ₁ Aly ₁ ) Nz ₁ (Tix 1 Aly 1). However, x ₁ , y ₁ and z ₁ are atomic ratios, respectively, and are represented by 0.26 ≤ x ₁ ≤ 0.4, 0.1 ≤ y ₁ ≤ 0.24, and x ₁ + y ₁ + z ₁ = 1). Titanium aluminum nitride film on the rake face and flank surface is at least 1000 μm away from the thinnest part (Tix ₂ Aly ₂ ) Nz ₂ (however, x ₂ , y ₂ and z ₂ is an atomic ratio, and has an Al-rich composition represented by _{0.06 ≤ x 2} ≤ 0.23, 0.25 ≤ y ₂ ≤ 0.45, and x ₂ + y ₂ + z _{2 = 1).} It is characterized by.

In the present specification, the cutting edge portion, the rake face, and the flank surface of the hard film coating tool are the cutting edge portion, the rake face, and the flank surface on the hard film surface, respectively. On the other hand, the cutting edge portion, the rake face, and the flank surface of the tool base are referred to as the base cut edge portion, the base rake face, and the base flank surface, respectively.

As shown in FIG. 1, the cutting edge portion 101 of the hard film coating tool (hard film) is located between _{the inflection point Q 1 of the rake face 102 and the inflection point Q 2} of the flank surface 103. On the other hand, the base 21, the base cutting edge portion 101 'substrate rake surface 102' located between the inflection point Q ₂ '' of the base flank 103 and 'inflection point to Q _1. As apparent from FIG. 1, the presence of the hard film, the inflection point Q ₂ inflection points Q ₁ and flank 103 of the rake face 102 of the hard-coated tool substrate rake surface 102 inflection point to Q ₁ ''and the base flank 103' present in the inflection point Q ₂ 'and different positions.

FIG. 2 (a) shows an example of the vertical cross section of the cutting edge portion 101 of the hard film coating tool. A cutting edge portion 101 having an arcuate vertical cross-sectional shape that gently protrudes is formed between the rake face 102 and the flank surface 103. Blade section 101 expired, the inflection point Q ₁ to the rake face 102 begins bending gradual, is formed in a region between the inflection point Q ₂ to which flank 103 begins bending gradual, the inflection point Q ₁ The arcuate cutting edge 101 between _{inflection point Q 2} and inflection point Q 2 has a width W. From the viewpoint of practicality, the width W of the arcuate cutting edge portion 101 is preferably 10 to 500 μm.

FIG. 2B shows another example of the vertical cross section of the cutting edge 101. In this example, a cutting edge portion 101 having a linear vertical cross-sectional shape is formed between the rake face 102 and the flank surface 103. In this example, the cutting edge portion 101 is formed in a region between the inflection point R ₂ inflection point R ₁ and the clearance surface 103 of the rake face 102, inflection point R ₁ and the inflection point R _The linear cutting edge 101 between 2 and 2 has a width W. From the viewpoint of practicality, the width W of the linear cutting edge portion 101 is also preferably 10 to 500 μm. The vertical cross-sectional shape of the cutting edge portion 101 shown in FIG. 2B is linear, but it may be polygonal.

In the hard film coating tool of the present invention, the base layer 22 and the titanium nitride aluminum film 23 mainly composed of columnar crystal structures are sequentially formed on the substrate 21. 6 (a) to 6 (c) are SEM photographs (magnification of 5,000 times) showing the layer configurations of the hard film cutting edge portion 101, the rake face 102, and the flank surface 103 of the hard film coating tool of the present invention, respectively. ..

(A) Tool base The tool base must be made of a highly heat-resistant material to which the chemical vapor deposition method can be applied. For example, WC-based cemented carbide, cermet, high-speed steel, tool steel, and cubic boron nitride are the main components. Examples thereof include boron nitride sintered body (cBN) and ceramics such as Sialon. From the viewpoint of strength, hardness, wear resistance, toughness and thermal stability, WC-based cemented carbide, cermet and ceramics are preferable. For example, in the case of WC-based cemented carbide, a titanium nitride aluminum film can be formed on the unprocessed surface as it is sintered, but it is formed on the processed surface (polished surface and cutting edge processed surface) in order to improve the dimensional accuracy of the tool. It is preferable to do so.

(B) Shape of the substrate FIG. 3 is a perspective view showing an example of the insert substrate used in the present invention. The illustrated substrate 21 is an insert for milling (base SEE42TN-C9), and has an upper surface (base rake surface) 102', a side surface (base relief surface) 103', and a base cutting edge 101'between them. Has. The substrate cutting edge portion 101'is formed by alternately connecting four substrate corner cutting edge portions 101a'and four substrate side cutting edge portions 101b' over the entire circumference. The illustrated insert 10 has an octagonal flat plate shape, and the side surface 103'has a corner side surface portion 103a'corresponding to each corner cutting edge portion 101a'and a side side surface portion 103b' corresponding to each side cutting edge portion 101b'. Has.

The substrate used in the present invention is not limited to FIG. 3, and inserts having other shapes (for example, solid type or cutting edge exchange type end mills, thread mills, drills, etc.) may be used.

(C) Titanium Aluminum Nitride Film The titanium aluminum nitride film in the hard film coating tool of the present invention contains Ti, Al and N as essential components. The titanium nitride aluminum film is formed on the cutting edge, the rake face, and the flank, and the titanium nitride aluminum film area formed on each is referred to as the "cutting edge titanium nitride aluminum film area" and the "rake surface titanium nitride aluminum film area". , And the flank titanium nitride aluminum film region.

FIG. 4A shows an example of the distribution of the Ti-rich portion and the Al-rich portion in the titanium nitride aluminum film 23 in the hard film coating tool (insert) 10 of the present invention. The Ti-rich portion is the cutting edge titanium nitride aluminum film region 101 _Ti in the cutting edge portion 101, the Ti rich portion (Ti rich rake surface titanium nitride aluminum film region) 102 _{Ti in the} rake face 102, and the flank 103. It consists of a Ti-rich part (Ti-rich flank titanium nitride aluminum film region) 103 _Ti . The Al-rich part is the Ti-rich part 102 on the rake face 102, the Al-rich part (Al-rich rake surface titanium nitride aluminum film region) 102 _{Al formed inside the Ti} , and the Ti-rich part on the flank surface 103. The Al-rich portion (Al-rich flank titanium nitride aluminum film region) formed below the _{103 Ti (the direction far from the cutting edge 101) is 103 Al} .

In Fig. 4 (a), the width of the Ti-rich rake face titanium nitride aluminum film region 102 _Ti (the thinnest part of the cutting edge titanium nitride aluminum film region and the inner edge of the _{Ti-rich rake face titanium nitride aluminum film region 102 Ti.} Distance) W ₂ , and Ti-rich flank titanium nitride aluminum film region 103 _Ti width (cutting edge between the thinnest part of the titanium nitride aluminum film region and the Ti-rich flank titanium nitride aluminum film region 103 _Ti Distance) W ₃ is less than 1000 μm. Further, on the rake face 102 side and the flank surface 103, _{the inside of the Ti-rich rake face titanium-aluminum nitride film region 102 Ti} (the side away from the cutting edge 101) and the Ti-rich flank surface titanium-aluminum nitride film region 103 _Ti . _{Al-rich rake face titanium aluminum nitride film region 102 Al} and Al-rich flank titanium aluminum nitride film region 103 _Al are formed below (the side away from the cutting edge 101), respectively. Therefore, the titanium nitride aluminum film 23 is surely Al-rich at the portion of the cutting edge 101 that is at least 1000 μm away from the thinnest portion of the titanium nitride aluminum film 23 on the rake face 102 side and the flank surface 103 side. In view of the above, in the present invention, the composition of the Al-rich rake face titanium nitride aluminum film region 102 _Al and the Al-rich flank titanium nitride aluminum film region 103 _Al is determined from the cutting edge portion 101 to the rake face 102 side and the flank 103. Measure at least 1000 μm away from the side. When the substrate 21 is placed on a shelf or the like to form a titanium nitride aluminum film, the Al-rich portion 103 _Al on the flank side may not be Al-rich. The composition of the titanium nitride aluminum film can be measured by EPMA under the conditions described below.

(1) Cutting edge titanium nitride aluminum film region
(a) Composition The cutting edge titanium nitride aluminum film region is (Tix ₁ Aly ₁ ) Nz ₁ (where x ₁ , y ₁ and z ₁ are 0.26 ≤ x ₁ ≤ 0.4 and 0.1 ≤ y ₁ ≤ 0.24, respectively. , And x ₁ + y ₁ + z ₁ = 1.) A Ti-rich titanium nitride aluminum film having a composition. Being Ti-rich improves fracture resistance (chipping resistance). Outside the composition range, the effect of improving fracture resistance is insufficient. The lower and upper limits of x ₁ are preferably 0.28 and 0.40, respectively, and the lower and upper limits of y ₁ are preferably 0.10 and 0.22, respectively. Further, from the viewpoint of high performance, the _{difference between x 1} and x ₂ is preferably 0.10 or more.

Within the above composition range of the cutting edge titanium nitride aluminum film region 101 _Ti , the atomic ratio of the metal atom (Ti + Al) is preferably 0.36 to 0.64, and the atomic ratio of the nitrogen atom (N) is 0.64 to 0.36. Is preferable. From the viewpoint of high performance, the atomic ratio of the metal atom (Ti + Al) is more preferably 0.38 to 0.62, and the atomic ratio of the nitrogen atom (N) is more preferably 0.62 to 0.38. 30 atomic% or less of N may be replaced with C and / or B. The cutting edge titanium nitride aluminum film region 101 _Ti may contain Cl as an unavoidable impurity, but the Cl content is preferably 1.5 atomic% or less, more preferably 0.8 atomic% or less.

_{(b) Film thickness The film thickness t 1} of the thinnest portion of the titanium nitride aluminum film region 101 _Ti of the cutting edge is preferably 2 to 13 μm, more preferably 3 to 11 μm. If the film thickness t ₁ is less than 2 μm, the coating effect of the film cannot be sufficiently obtained. On the other hand, if the film thickness t ₁ exceeds 13 μm, the film becomes too thick and cracks occur inside the film, which may shorten the life. A particularly preferable film thickness t ₁ is 4 to 9 μm. The film thickness of the titanium nitride aluminum film region 101 _Ti of the cutting edge can be appropriately controlled by the film formation time.

The film thickness t ₁ is measured by the following method. For example, when the hard film coating tool is an insert, two samples for film thickness measurement are prepared, and in each sample, position P ₁ and position P _{1 on the cutting edge 101 of the insert shown in FIG. 4 (a).} Each sample is broken along _{position P 2} on the rake face 102 1000 μm away from _{and position P 3} on the flank 103 1000 μm away from position P _1. FIG. 4 (b) shows the vertical fracture surface 115 of the sample. The longitudinal fracture section 115 of FIG. 4 (b) shows SEM photographs of the longitudinal section of the cutting edge portion of the insert (first sample) of Example 1 in FIGS. 5 (500 times) and 6 (a) (5,000). Double). For the second sample, take the same SEM photographs as in Fig. 5 and Fig. 6 (a). From the SEM photographs of the two samples obtained, the film thickness of the thinnest portion of the cutting edge portion 101 of the titanium nitride aluminum film 23 is measured, and the average value of the obtained measured values is defined as the film thickness t ₁ .

(c) Crystal structure The cutting edge titanium nitride aluminum film region 101 _Ti is preferably composed mainly of a columnar crystal structure. Further, under the nanobeam diffraction (NAD) condition described later, it is preferable to have a crystal structure mainly composed of at least an fcc structure, and it is more preferable to have a single structure of fcc.

The cutting edge titanium nitride aluminum film region 101 _Ti has a higher Ti content than the Al-rich rake face titanium nitride aluminum film region 102 _Al and the Al-rich flank titanium nitride aluminum film region 103 _Al , so that it has fracture resistance (fracture resistance). Excellent chipping property).

(2) Ti-rich titanium nitride aluminum film region Of the rake face 102 and flank 103, _{the region adjacent to Ti-rich cutting edge titanium nitride aluminum film region 101 Ti} is the Ti-rich rake face titanium aluminum nitride film region, respectively. 102 _Ti and Ti Rich flank titanium nitride aluminum film region 103 _Ti . In FIG. 4 (a), Ti-rich rake face titanium aluminum nitride coating region 102 _Ti width W ₂ and Ti-rich flank titanium aluminum nitride coating region 103 _Ti width W ₃ of the both is less than 1000 .mu.m. The widths W ₂ and W ₃ are both preferably 800 μm or less, and more preferably 600 μm or less.

(a) Composition
The composition of the Ti-rich rake face titanium aluminum nitride coating region 102 _Ti, and Ti-rich flank titanium aluminum nitride coating region 103 _Ti has a Ti-rich composition close to the titanium cutting edge aluminum nitride film region 101 _Ti.

(b) Crystal structure
The crystal structures of the Ti-rich rake face titanium aluminum nitride film region 102 _Ti and the Ti-rich flank titanium nitride aluminum film region 103 _Ti are preferably mainly columnar crystal structures, and substantially only from columnar crystal structures. It is more preferable to be.

(c) Crystal structure
The crystal structures of the Ti-rich rake face titanium nitride aluminum film region 102 _Ti and the Ti-rich flank titanium nitride aluminum film region 103 _Ti are crystal structures mainly composed of at least the fcc structure under the nanobeam diffraction (NAD) conditions described later. , And more preferably a single structure of fcc.

(3) Al-rich titanium nitride aluminum film region
Inner Ti rich rake face titanium aluminum nitride coating region 102 _Ti, and Ti-rich flank under the titanium aluminum film region 103 _Ti nitride, titanium Al-rich rake face nitride each aluminum film region 102 _Al and Al-rich relief There is a surface titanium nitride aluminum film region 103 _Al . Ti-rich rake face Titanium nitride aluminum film region 102 _Ti width W ₂ and Ti-rich flank titanium nitride aluminum film region 103 _Ti width W ₃ are both less than 1000 μm, so titanium nitride aluminum nitride in the cutting edge 101 _{Al-rich rake surface titanium nitride aluminum film region 102 Al} and Al-rich flank titanium aluminum nitride film region 103 _Al at a distance of at least 1000 μm from the thinnest part of the film 23 to the rake face 102 side and the flank surface 103 side. Measure the composition.

(a) Composition
Al-rich rake face titanium nitride aluminum film region 102 _Al and Al-rich flank titanium nitride aluminum film region 103 _Al are both at least 1000 μm away from the thinnest part of the cutting edge titanium nitride aluminum film region 101 _Ti. , (Tix ₂ Aly ₂ ) Nz ₂ (However, x ₂ , y ₂ and z ₂ are 0.06 ≤ x ₂ ≤ 0.23, 0.25 ≤ y ₂ ≤ 0.45, and x ₂ + y ₂ + z ₂ = 1 respectively. It has a composition of.). By being Al-rich, heat resistance (oxidation resistance) is improved. The heat resistance is insufficient outside the composition range. The lower and upper limits of x ₂ are preferably 0.08 and 0.22, and the lower and upper limits of _{y 2 are preferably 0.26 and 0.43.} Further, from the viewpoint of high performance, the _{difference between y 2} and y ₁ is preferably 0.10 or more.

Within the above composition range of the Al-rich titanium nitride aluminum film region, the atomic ratio of metal atoms (Ti + Al) is preferably 0.31 to 0.68, and the atomic ratio of nitrogen atoms (N) is 0.69 to 0.32. Is preferable. From the viewpoint of high performance, the atomic ratio of the metal atom (Ti + Al) is more preferably 0.34 to 0.65, and the atomic ratio of the nitrogen atom (N) is more preferably 0.66 to 0.35. 30 atomic% or less of N may be replaced with C and / or B. The Al-rich rake face titanium aluminum nitride film region 102 _Al and the Al-rich flank titanium nitride aluminum film region 103 _Al may contain Cl as an unavoidable impurity, but the Cl content is 1.5 atomic% or less. It is preferably 0.8 atomic% or less, and more preferably 0.8 atomic% or less.

(b) In order to have excellent heat resistance on the rake face and flank surface, in Fig. 4 (b), the film thickness t ₂ at position P _{2 of the Al-rich rake face titanium nitride aluminum film region 102 Al} and The film thickness t _{3 at} the position P ₃ of the Al-rich flank titanium nitride aluminum film region 103 _Al is preferably 5 to 15 μm, and more preferably 6 to 12 μm, respectively. If the film thicknesses t ₂ and t ₃ are less than 5 μm, the coating effect of the film cannot be sufficiently obtained. If the film thicknesses t ₂ and t ₃ exceed 15 μm, the film may become too thick and cracks may occur inside the film. The film thickness t ₂ is measured by the following method. Take SEM photographs of the same two samples used to measure the film thickness t ₁ at the longitudinal fracture section 115 [Fig. 4 (b)] _{at position P 2 on the rake face 102, respectively.} FIG. 6 (b) is an SEM photograph (magnification of 5,000 times) showing the measurement position _{of the film thickness t 2} in the first sample of the same example. The film thickness t _{2 of the second} sample is also measured in the same manner as described above, and the average value of the measured values is defined as the film thickness t ₂ . The film thickness t _{3 is} also measured _{at position P 3} in the same manner as the film thickness t _2.

When the hard film coating tool of the present invention is a solid type or blade tip exchange type end mill or the like, the cutting edge portion of the end mill or the like is _{separated from the measurement position of the film thickness t 1} by 1000 μm on the rake face side and the flank surface side, respectively. The film thicknesses t ₂ and t ₃ can be obtained at the position in the same manner as above.

(c) Film thickness ratio t ₁ / t ₂ and t ₁ / t ₃
Cutting edge Titanium nitride aluminum film region 101 _Ti thinnest part thickness t ₁ and Al-rich rake face Titanium nitride aluminum film region 102 _Al position P ₂ thickness t ₂ and Al-rich flank titanium aluminum nitride The film thickness ratios t ₁ / t ₂ and t ₁ / t ₃ to the film thickness t _{3 at} the position P ₃ of the film region 103 _Al are both preferably 0.35 to 0.85. If the film thickness ratios t ₁ / t ₂ and t ₁ / t ₃ are both less than 0.35, the coating effect of the film cannot be sufficiently obtained. If the film thickness ratios t ₁ / t ₂ and t ₁ / t ₃ both exceed 0.85, the film becomes too thick and cracks occur inside the film, resulting in a short life.

The film thicknesses t ₁ , t ₂ , and t ₃ are obtained by measuring the titanium nitride aluminum nitride film as it is formed when the film-forming post-deposition cutting edge treatment is not performed. This is a measurement of the titanium nitride aluminum film after the treatment. Decrease in the film thickness t _2, t ₃ thickness t ₁ and the rake face and the flank face of the cutting edge portion by edge processing is very small, before and after edge processing thickness ratio t ₁ / t _2, t ₁ / t ₃ is almost the same, and it is preferable that all of them are 0.35 to 0.85.

(d) Crystal structure
It is preferable that both the Al-rich rake face titanium aluminum nitride film region 102 _Al and the Al-rich flank titanium nitride aluminum film region 103 _Al have a columnar crystal structure. Further, under the nanobeam diffraction (NAD) condition described later, it is preferable to have a crystal structure mainly composed of at least an fcc structure, and it is more preferable to have a single structure of fcc.

(D) Base layer Although not particularly limited, from the viewpoint of prolonging the service life, the base layer 22 between the base 21 and the titanium nitride aluminum film 23 is a Ti (CN) film, a TiN film, and a TiZr (CN) film. It is preferable to provide at least one of these films by a chemical vapor deposition method. A TiN film is particularly preferable as the base layer 22. The film thickness of the base layer 22 is preferably about 0.05 to 0.1 μm.

(E) Upper layer On the titanium nitride aluminum film 23, at least one element selected from the group consisting of Ti, Al, Cr, B and Zr, and a group consisting of C, N and O are selected. A single-layer or multi-layer hard film that requires at least one of the above elements may be formed by a chemical vapor deposition method. As the upper layer, for example, TiC, CrC, SiC, VC, ZrC, TiN, TiAlN, CrN, Si ₃ N ₄ , VN, ZrN, Ti (CN), (TiSi) N, (TiB) N, TiZrN, TiAl (CN) ), TiSi (CN), TiCr (CN), TiZr (CN), Ti (CNO), TiAl (CNO), Ti (CO), TiB _2, etc. Can be mentioned.

[2] Chemical Vapor Deposition Equipment The hard film coating tool of the present invention can be formed by a chemical vapor deposition method using a thermochemical vapor deposition apparatus or a plasma-assisted chemical vapor deposition apparatus (CVD furnace). As shown in FIG. 8, the chemical vapor deposition apparatus (CVD furnace) 1 includes a chamber 2, a heater 3 provided in the wall of the chamber 2, a plurality of shelves 4, 4, and a reaction vessel that covers the shelves 4, 4. 5 and a plurality of partition plates 6 and 6 provided between the shelves 4 and 4, and first and second pipes 11 and 12 vertically penetrating the central opening 40 of the shelves 4 and 4. , Each of the pipes 11 and 12 is provided with a plurality of nozzles 11a and 12a, and the reaction vessel 5 is provided with a plurality of discharge holes 5a. The first pipe 11 and the second pipe 12 penetrate the bottom of the chamber 2 so that they can rotate integrally, and are rotatably connected to an external pipe (not shown). At the bottom of the chamber 2, there is a pipe 13 for discharging the carrier gas and the unreacted gas among the raw material gases ejected from the first and second pipes 11 and 12.

[3] Manufacturing Method The hard film coating tool of the present invention will be described in detail below by taking the case of using the thermochemical vapor deposition method as an example, but of course, the present invention is not limited to this, and can be applied to other chemical vapor deposition methods. ..

(A) Formation of base layer When a TiN film is used as the base layer, H ₂ gas and, if necessary, N ₂ gas and / or Ar gas are flowed into the CVD furnace 1 in which the base is set, and the temperature rises to the film formation temperature. After warming, a _{raw material gas composed of TiCl 4} gas, N ₂ gas and H ₂ gas is flowed into the CVD furnace 1 to form a TiN film of the underlying layer.

When a Ti (CN) film is used as the base layer, H ₂ gas and, if necessary, N ₂ gas and / or Ar gas are flowed into the CVD furnace 1 in which the substrate is set, and the temperature is raised to the film formation temperature. A _{raw material gas consisting of TiCl 4} gas, CH ₄ gas, N ₂ gas and H ₂ gas, or TiCl ₄ gas, CH ₃ CN gas, N ₂ gas and H ₂ gas is flowed into the CVD furnace, and the Ti (CN) of the underlying layer is poured. ) Form a film.

When a TiZr (CN) film is used as the base layer, H ₂ gas and, if necessary, N ₂ gas and / or Ar gas are flowed into the CVD furnace 1 in which the substrate is set, and the temperature is raised to the film formation temperature. TiCl ₄ gas, CH ₄ gas, N ₂ gas, H ₂ gas and Zr Cl ₄ gas, or _{a raw material gas consisting of TiCl 4} gas, ZrCl ₄ gas, CH ₃ CN gas, N ₂ gas and H ₂ gas is put into the CVD furnace 1. To form a TiZr (CN) film of the base layer.

(B) Formation of titanium nitride aluminum film
(1) Raw material gas
The raw material gas forming the titanium aluminum nitride film having a single structure of fcc is 0.1 to 0.8% by volume, where the total of _{TiCl 4} gas, AlCl ₃ gas, NH ₃ gas, N ₂ gas and H _{2 gas is 100% by volume.} TiCl ₄ gas, 0.4 to 1.2% by volume AlCl ₃ gas, 4.0 to 23.5% by volume N ₂ gas, and the balance H ₂ gas, and the volume ratio of TiCl _{4 gas to AlCl 3 gas (TiCl 4} / AlCl _3). ) Is 0.3 to 0.7, and 0.7 to 1.9% by volume of NH ₃ gas, 3 to 16.5% by volume of N ₂ gas, and the balance H ₂ gas. In the raw material gases A and B, _{a part of the H 2} gas which is a carrier gas may be replaced with an Ar gas. The composition of the mixed gas A is preferably 0.2 to 0.7% by volume of TiCl ₄ gas, 0.5 to 1.1% by volume of AlCl ₃ gas, 4.3 to 23.2% by volume of N ₂ gas, and the balance H ₂ gas, preferably AlCl ₃ gas. The volume ratio of TiCl _{4 gas to TiCl 4 (TiCl 4} / AlCl ₃ ) is preferably 0.3 to 0.6. The composition of the mixed gas A is more preferably composed of 0.2 to 0.6% by volume of TiCl ₄ gas, 0.5 to 1.0% by volume of AlCl ₃ gas, 5 to 22% by volume of N ₂ gas, and the balance H _{2 gas.} The composition of the mixed gas B is preferably 0.7 to 1.8% by volume of NH ₃ gas, 4 to 16% by volume of N ₂ gas, and the balance H ₂ gas.

(a) Mixed gas A
If the TiCl ₄ gas is less than 0.1% by volume, the Al content of the titanium nitride aluminum film becomes excessive, and the wear resistance and the fracture resistance are lowered. On the other hand, when the TiCl ₄ gas exceeds 0.8% by volume, the Ti content of the titanium nitride aluminum film becomes excessive, and the oxidation resistance and heat resistance are lowered. The TiCl ₄ gas content is preferably 0.2 to 0.7% by volume.

If the AlCl ₃ gas is less than 0.4% by volume, the Al content of the titanium nitride aluminum film becomes too small, and the oxidation resistance and heat resistance of the rake face and flank surface of the titanium nitride aluminum film decrease. If the AlCl ₃ gas exceeds 1.2% by volume, the Al content of the titanium nitride aluminum film becomes excessive, and the wear resistance and fracture resistance deteriorate. The AlCl ₃ gas content is preferably 0.5 to 1.1% by volume.

When the N ₂ gas is less than 4.0% by volume or more than 23.5% by volume, the reaction rate of the raw material gas changes, and the film thickness distribution of the titanium nitride aluminum hard film formed on the substrate placed in the CVD furnace is poor. Become. The content of N ₂ gas is preferably 4.9 to 21.8% by volume.

If the volume ratio of TiCl _{4 gas to AlCl 3 gas (TiCl 4} / AlCl ₃ ) is less than 0.3, the Al content of the titanium nitride aluminum film becomes excessive, and wear resistance and fracture resistance deteriorate. When (TiCl ₄ / AlCl ₃ ) is more than 0.7, the Al content of the titanium nitride aluminum film becomes too small, and the oxidation resistance and heat resistance of the titanium nitride aluminum film on the rake face and the flank surface decrease. (TiCl ₄ / AlCl ₃ ) is preferably 0.3 to 0.6.

(b) Mixed gas B
Whether the NH ₃ gas is less than 0.7% by volume or more than 1.9% by volume, the reaction rate of the raw material gas changes, and the cutting edge titanium nitride aluminum film region, the rake face titanium nitride aluminum film region, and the flank titanium nitride aluminum film region are changed. No film area can be obtained. The content of NH ₃ gas is preferably 0.7 to 1.8% by volume.

When the N ₂ gas is less than 3% by volume or more than 16.5% by volume, the reaction rate of the raw material gas changes, and the film thickness distribution of the titanium nitride aluminum film formed on the substrate placed in the CVD furnace 1 is poor. Become. The content of N ₂ gas is preferably 4 to 16% by volume.

(2) Method of introducing raw material gas In order to form a titanium nitride aluminum film with different compositions on the cutting edge, rake face and flank surface, highly reactive mixed gas A and mixed gas B are put into CVD furnace 1. It must be delivered in a non-contact state. Therefore, the mixed gas A may be ejected from the first nozzle 11a of the first pipe 11, the mixed gas B may be ejected from the second nozzle 12a of the second pipe 12, and the mixed gas A may be ejected from the second nozzle 12a. The mixed gas B may be ejected from the second nozzle 12a of the pipe 12 of the first pipe 11 and the mixed gas B may be ejected from the second nozzle 11a of the first pipe 11.

As shown in FIG. 8, the first nozzle 11a is arranged on the outer peripheral side and the second nozzle 12a is arranged on the center side so as not to obstruct the flow of the mixed gases A and B ejected from each nozzle. .. The first and second pipes 11 and 12 preferably rotate at a speed of 2 to 4 rpm, but their directions of rotation are not limited.

In FIG. 8, the first pipe 11 has a plurality of first nozzles 11a, 11a arranged vertically, and the second pipe 12 has a plurality of second nozzles 12a arranged vertically. .. The first nozzle 11a ejects one of the raw material gases A and B, and the second nozzle 12a ejects the other of the raw material gases A and B.

Preferred examples of the pipe assembly having the first and second nozzles for introducing the mixed gases A and B into the CVD furnace 1 in a non-contact manner are shown in FIGS. 9 to 11.

(a) First pipe assembly An example of the pipe assembly shown in FIG. 9 (first pipe assembly 30) consists of two first pipes 11 and 11 and one second pipe 12. , Both ends of the first and second pipes 11, 11 and 12 are integrally fixed by holding members (not shown).

The first pipe 11 has a radius R ₁ and the second pipe 12 has a radius R ₂ . _{The central axis O 1} of the first pipe 11 is located on the circumference C _{1 of the first diameter D 1} centered on the rotation axis O. Therefore, the two first pipes 11 and 11 are equidistant from the axis of rotation O. _{The central angle θ of the central axes O 1} and O ₁ of the first pipes 11 and 11 with respect to the rotation axis O is preferably 90 to 180 °. Further, the central axis O ₂ of the second pipe 12 coincides with the rotation axis O, and the outer circumference of the second pipe 12 has a second diameter D ₂ (= 2R ₂ ) centered on the rotation axis O. Consistent with circumference C _2.

The first nozzles 11a and 11a of the first pipes 11 and 11 face outward in the opposite direction (180 ° direction). In the illustrated example, each first pipe 11 has one row of first nozzles 11a in the vertical direction, but the present invention is not limited to this, and the first nozzles 11a may have a plurality of rows. Further, the second pipe 12 has two rows of second nozzles 12a and 12a arranged in the radial direction (180 ° direction). Of course, the second nozzle 12a is not limited to two rows, and may be one row. Since the first diameter D ₁ is larger than the second diameter D ₂ , [D ₁ ≥ 2 (R ₁ + R ₂ )], when the pipe assembly 30 rotates about the rotation axis O, the first nozzle 11a, 11a is located on the outer peripheral side, and the second nozzles 12a and 12a are located on the inner peripheral side.

If the second pipe 12 has a row of second nozzles 12a and _{the central angles θ of the central axes O 1} and O ₁ of the first pipes 11 and 11 are less than 180 °, the second nozzle 12a Is preferably oriented in the direction far from the first nozzles 11a and 11a (opposite the central angle θ). In this case, it is preferable that the ejection direction of the first nozzle 11a and the ejection direction of the second nozzle 12a are orthogonal to each other.

_{The central axes O 1} and O _{1 of} the first pipes 11 and 11 are on the same straight line as the central axis O _{2 of} the second pipe 12, and the second pipe 12 is the second nozzle 12a and 12a in two rows. The first nozzles 11a and 11a are oriented in the opposite direction (180 ° direction), and the second nozzle 12a is oriented in the direction orthogonal to the first nozzles 11a and 11a. (It has a central angle of 90 °) is preferable.

A first nozzle 11a on the outer peripheral side that ejects one of the mixed gases A and B in order to form a titanium nitride aluminum film having a different composition between the cutting edge portion and the rake face and the flank surface in the present invention. the ratio of the ejection port and the distance H ₁ between the rotation axis O, the distance of H ₂ gas mixture a and the other spout of the second nozzle 12a of the circumferential side for jetting out the B and the rotation axis O ( H ₁ / H ₂ ) is preferably in the range of 1.5 to 3.

(b) Second pipe assembly Fig. 10 shows another example of a pipe assembly (second pipe assembly 33) in which the mixed gas A and the mixed gas B are introduced into the CVD furnace 1 in a non-contact state. .. The pipe assembly 33 is composed of one first pipe 11 and one second pipe 12, and both ends of the first and second pipes 11 and 12 are integrally formed by holding members (not shown). It is fixed. The first pipe 11 has a row of first nozzles 11a, and the second pipe 12 also has a row of second nozzles 12a in the vertical direction.

_{The central axis O 2} of the second pipe 12 coincides with the rotation axis O of the pipe assembly 33, and the first pipe 11 is located close to the second pipe 12. The first pipe 11 has a radius R ₁ and the second pipe 12 has a radius R ₂ . _{The central axis O 1} of the first pipe 11 is located on the circumference C _{1 of} the first diameter D ₁ centered on the rotation axis O, and the central axis O _{2 of the second pipe 12 is the rotation axis O.} It coincides, and its outer circumference coincides with the circumference C _{2 of the second diameter D 2} (= 2R ₂ ) centered on the axis of rotation O. Since the first diameter D ₁ is larger than the second diameter D ₂ , [D ₁ ≥ 2 (R ₁ + R ₂ )], when the pipe assembly 40 rotates about the rotation axis O, the first nozzle 11a has an outer circumference. It is located on the side, and the second nozzle 12a is located on the inner peripheral side.

In the illustrated example, the first nozzle 11a of the first pipe 11 and the second nozzle 12a of the second pipe 12 are oriented in the opposite directions (180 ° direction), but of course, they are not limited. The central angle between the first nozzle 11a and the second nozzle 12a may be within the range of 90 to 180 °.

(c) Third pipe assembly Fig. 11 shows yet another example of a pipe assembly (third pipe assembly 36) in which the mixed gas A and the mixed gas B are introduced into the CVD furnace 1 in a non-contact state. show. This pipe assembly 36 consists of four first pipes 11, 11, 11, 11 and one second pipe 12, both ends of the first and second pipes 11, 11, 11, 11, 12. The portion is integrally fixed by a holding member (not shown). Each first pipe 11 has a vertical row of first nozzles 11a, and a second pipe 12 has two vertical rows of second nozzles arranged in orthogonal radial directions (180 °). It has 12a, 12a, 12a, and 12a. The first nozzles 11a, 11a, 11a, 11a of all the first pipes 11, 11, 11, 11 are facing outward.

The first pipe 11 has a radius R ₁ and the second pipe 12 has a radius R ₂ . _{The central axis O 1} of the first pipe 11 is located on the circumference C _{1 of the first diameter D 1} centered on the rotation axis O. Therefore, the four first pipes 11, 11, 11, 11 are equidistant from the axis of rotation O. Further, the central axis O ₂ of the second pipe 12 coincides with the rotation axis O, and the outer circumference thereof coincides with the circumference C _{2 of the second diameter D 2} (= 2R _{2) centered on the rotation axis O.} I am doing it. Since the first diameter D ₁ is larger than the second diameter D ₂ , [D ₁ ≥ 2 (R ₁ + R ₂ )], when the pipe assembly 36 rotates about the rotation axis O, the first nozzles 11a, 11a , 11a, 11a are located on the outer peripheral side, and the second nozzles 12a, 12a, 12a, 12a are located on the inner peripheral side. In the example shown the central angle θ about the rotation axis O of the center axis O _1, O ₁ of the first pipe 11 adjoining a 90 °, without being limited thereto, may be a 60 to 120 ° ..

(3) Film formation temperature The film formation temperature of the titanium nitride aluminum film is preferably 750 to 830 ° C, more preferably 780 to 820 ° C. If the film formation temperature is less than 750 ° C., the chlorine content of the titanium nitride aluminum film increases and the film hardness decreases. On the other hand, when the film formation temperature exceeds 830 ° C., the reaction is promoted too much and a granular crystal structure is formed, which is inferior in oxidation resistance and heat resistance. The film formation temperature is determined by providing a thermocouple (not shown) at a position close to the reaction vessel 5 in the CVD furnace 1 shown in FIG. 8 and measuring the furnace body temperature during film formation.

(4) Film formation pressure The film formation pressure of the titanium nitride aluminum film is preferably 3 to 6 kPa. If the film forming pressure is less than 3 kPa, the cutting edge titanium nitride aluminum film region, the rake face titanium nitride aluminum film region, and the flank surface titanium nitride aluminum film region cannot be obtained. On the other hand, when the film forming pressure exceeds 6 kPa, the titanium nitride aluminum film becomes a granular crystal structure and is inferior in oxidation resistance and heat resistance.

(5) Gas flow path Fig. 12 shows an example of a shelf 4 made for the purpose of facilitating the flow of raw material gas around each substrate 10 in the CVD furnace 1. Two through holes 4a are provided in the vicinity of each side of each of the substrates 10 placed on the shelf 4. The arrows in FIG. 12 indicate the direction of rotation of the first pipe assembly 30.

FIG. 13 schematically shows a partial cross-sectional view of the CVD furnace 1 when the shelves 4 and 4 shown in FIG. 12 are used. The first nozzle 11a and the second nozzle 12a (not shown) are provided between each shelf 4 and the partition plate 6 above the shelf 4. The discharge hole 5a of the reaction vessel 5 is formed between each shelf 4 and the partition plate 6 above it (upper space of the shelf 4) and between each partition plate 6 and the upper shelf 4 (lower space of the shelf 4). ) Are provided respectively.

FIG. 14 shows a gas flow path G when, for example, the mixed gas A is ejected from the first nozzle 11a. A part of the mixed gas A ejected into the upper space of the shelf 4 passes through the upper space as it is, and is discharged from the discharge hole 5a provided in the upper space. The remaining portion of the mixed gas A ejected into the upper space of the shelf 4 passes through the through hole 4a of each shelf 4 and flows into the lower space from the upper space of the shelf 4, and the discharge hole 5a provided in the lower space. Is discharged from. With this configuration, a gas flow path G is formed in which a part of the mixed gas A passes through the through hole 4a of each shelf 4. FIG. 14 shows that the mixed gas B blown out from the second nozzle 12a of the second pipe 12 also forms the gas flow path G in the same manner as the mixed gas A. Since the through hole 4a is provided in the vicinity of the corner portion of each substrate 10, both the mixed gas A and the mixed gas B passing through the through hole 4a mainly pass in the vicinity of the corner portion of each substrate 10. Therefore, it is considered that the probability that the mixed gas A and the mixed gas B react on the surface of each substrate 10 increases. When the mixed gas A is ejected from the second nozzle 12a and the mixed gas B is ejected from the first nozzle 11a, the gas flow path G is formed in the same manner as described above.

FIG. 15 shows another example of shelf 4. The shelf 4 of FIG. 15 differs from the shelf 4 of FIG. 12 in that three through holes 4b are provided in the vicinity of each side of each substrate 10. With such a configuration, it is considered that the probability that the mixed gas A and the mixed gas B react on the surface of each substrate 10 is further increased. The arrows in FIG. 15 indicate the direction of rotation of the first pipe assembly 30.

(C) Formation of upper layer Although not particularly limited, an upper layer can be formed on the titanium nitride aluminum film by a known chemical vapor deposition method. The film formation temperature may be 700 to 830 ° C. Examples of the raw material gas used to form the upper layer are as follows.
1. TiC film TiCl ₄ gas, CH ₄ gas and H ₂ gas.
2. CrC film CrCl ₃ gas, CH ₄ gas and H ₂ gas.
3. SiC film SiCl ₄ gas, CH ₄ gas and H ₂ gas.
4. VC film VCl gas, CH ₄ gas and H ₂ gas.
5. ZrC film ZrCl ₄ gas, CH ₄ gas and H gas.
6. TiN film TiCl ₄ gas, N ₂ gas and H ₂ gas.
7. AlN film AlCl ₃ gas, NH ₄ gas and H ₂ gas.
8. CrN film CrCl ₃ gas, NH ₄ gas and H ₂ gas.
9. Si ₃ N ₄ film SiCl ₄ gas, NH ₄ gas and H ₂ gas.
10. VN film VCl ₃ gas, NH ₄ gas and H ₂ gas.
11. ZrN film ZrCl ₄ gas, N ₂ gas and H ₂ gas.
12. Ti (CN) film TiCl ₄ gas, CH ₄ gas, N ₂ gas and H ₂ gas, or _{Ti Cl 4} gas, CH ₃ CN gas, N ₂ gas and H ₂ gas.
13. (TiSi) N film TiCl ₄ gas, SiCl ₄ gas, N ₂ gas and NH ₃ gas.
14. (TiB) N film TiCl ₄ gas, N ₂ gas and BCl ₃ gas.
15. TiZr (CN) film TiCl ₄ gas, ZrCl ₄ gas, N ₂ gas, CH ₄ gas and H ₂ gas, or TiCl ₄ gas, ZrCl ₄ gas, N ₂ gas, CH ₃ CN gas and H ₂ gas.
16. TiAl (CN) film TiCl ₄ gas, AlCl ₃ gas, N ₂ gas, CH ₄ gas, NH ₃ gas and H ₂ gas, or TiCl ₄ gas, AlCl ₃ gas, N ₂ gas, CH ₃ CN gas and H ₂ gas.
17. TiSi (CN) film TiCl ₄ gas, SiCl ₄ gas, N ₂ gas, CH ₄ gas, NH ₃ gas and H ₂ gas, or TiCl ₄ gas, SiCl ₄ gas, N ₂ gas, CH ₃ CN gas and H ₂ gas.
18. TiCr (CN) film TiCl ₄ gas, CrCl ₃ gas, N ₂ gas, CH ₄ gas, NH ₃ gas and H ₂ gas, or TiCl ₄ gas, CrCl ₃ gas, N ₂ gas, CH ₃ CN gas and H ₂ gas.
19. TiV (CN) coating TiCl ₄ gas, VCl ₃ gas, N ₂ gas, CH ₄ gas, NH ₃ gas and H ₂ gas, or TiCl ₄ gas, VCl ₃ gas, N ₂ gas, CH ₃ CN gas and H ₂ gas.
20. TiZr (CN) film TiCl ₄ gas, ZrCl ₃ gas, N ₂ gas, CH ₄ gas, NH ₃ gas and H ₂ gas, or TiCl ₄ gas, ZrCl ₄ gas, N ₂ gas, CH ₃ CN gas and H ₂ gas.
21. Ti (CNO) film TiCl ₄ gas, N ₂ gas, CH ₄ gas, CO gas and H ₂ gas, or _{Ti Cl 4} gas, N ₂ gas, CH ₃ CN gas, CO gas and H ₂ gas.
22. TiAl (CNO) film TiCl ₄ gas, AlCl ₃ gas, N ₂ gas, CH ₄ gas, CO gas and H ₂ gas, or TiCl ₄ gas, AlCl ₃ gas, N ₂ gas, CH ₃ CN gas, CO gas And H ₂ gas.
23. Ti (CO) film TiCl ₄ gas, N ₂ gas, CH ₄ gas, CO gas, CO ₂ gas and H ₂ gas.
24. TiB ₂ film TiCl ₄ gas, BCl ₃ gas, H ₂ gas.

(D) Cutting edge treatment after coating with a hard film The titanium aluminum nitride film formed on the substrate is smoothed by treatment with a brush, buff, blast, etc., resulting in a surface state with excellent chipping resistance. In particular, when a ceramic powder such as alumina, zirconia, or silica is used as a projection material and the cutting edge of the hard film is treated by a wet or dry blasting method, the surface of the hard film is smoothed and the chipping resistance is improved.

[4] Mechanism of the present invention At least the composition of the titanium nitride aluminum film region of the cutting edge is Ti-rich, and the flank titanium aluminum nitride film region of Ti-rich and the Ti-rich rake face titanium aluminum nitride film region of Ti-rich are adjacent to the cutting edge. The mechanism by which the Al-rich flank titanium nitride aluminum film region and the Al-rich rake face titanium nitride aluminum film region are formed is not necessarily clear, but is considered as follows. That is, the TiCl ₄ gas and the AlCl _{3 gas in the mixed gas A are extremely reactive with the NH 3} gas in the mixed gas B, and react rapidly when introduced into the CVD furnace.

For example, if the distance between the spout of the nozzle for mixed gas B and the coating (base) is shorter than the distance between the spout of the nozzle for mixed gas A and the covering, the mixed gas until the mixed gas A reaches the covering The reaction with B is reduced. On the contrary, even if the distance between the ejection port of the nozzle for mixed gas A and the coating (base) is shorter than the distance between the ejection port of the nozzle for mixed gas B and the coating, until the mixed gas B reaches the coating. Reaction with the mixed gas A is reduced. In the mixed gas A, the volume ratio of TiCl _{4 gas to AlCl 3 gas (TiCl 4} / AlCl ₃ ) is 0.3 to 0.7, and _{the ratio of AlCl 3} gas is high. Therefore, the titanium aluminum nitride film immediately after film formation has a columnar crystal structure. It has a microstructure composed of an Al-rich TiAlN phase and a Ti-rich TiAlN phase. In the Al-rich TiAlN phase, Al is dissolved in Ti, so the more Al-rich TiAlN phase, the larger the internal strain. On the other hand, in the cutting edge portion where the rake face and the flank intersect, the stress is remarkably concentrated more than the flat rake face and the flank. Since the periphery of the cutting edge is also affected by the cutting edge, the internal strain increases. When an Al-rich TiAlN phase having a high internal strain is formed on the cutting edge portion having a high internal strain and its periphery by the method of the present invention, the Al-rich TiAlN phase has its own internal strain and the cutting edge portion and its periphery. Self-destruction due to peeling, etc. due to the synergistic effect of stress concentration in the surrounding area. As a result, a Ti-rich titanium nitride aluminum film is formed on and around the cutting edge. On the other hand, in the rake face titanium nitride aluminum film region and the flank titanium nitride aluminum film region separated from the cutting edge by a certain distance (for example, 1000 μm), stress concentration unlike the titanium nitride aluminum film region of the cutting edge does not occur. A rich state is maintained.

_{Similar to the above, the mechanism by which the thinnest film thickness t 1} is generated in the titanium nitride aluminum film region of the cutting edge is also the specific part of the cutting edge during film formation due to the internal strain accumulated concentrated in the cutting edge. It is considered that this is because the self-destruction of the film in the above is remarkably advanced.

Within the composition range of the raw material gas used in the present invention, the larger the volume% (flow rate) of the total of _{TiCl 4} gas, AlCl ₃ gas and NH _{3 gas, the more the film thickness ratios t 1} / t ₂ and t ₁ / t _{3 become.} It decreases and the Ti-rich part formed on the rake face and flank surface expands. It _{is considered that the larger the volume% (flow rate) of TiCl 4} gas, AlCl ₃ gas, and NH ₃ gas is, the more the reaction between the mixed gas A and the mixed gas B at the time of film formation is activated, so that the above phenomenon occurs.

The present invention will be described in more detail with reference to the following examples, but the present invention is, of course, not limited thereto. In the following examples and comparative examples, the flow rate (L / min) is the flow rate under the conditions of 1 atm and 25 ° C. The thickness of each layer is an average value.

Example 1
(1) Formation of base layer Made of WC-based cemented carbide (consisting of 11.5% by mass Co, 2.0% by mass TaC, 0.7% by mass CrC, balance WC and unavoidable impurities), which is schematically shown in Fig. 3. Milling insert substrate (SEE42EN-C9) and WC-based cemented carbide (7% by mass Co, 0.6% by mass CrC, 2.2% by mass ZrC, 3.3% by mass TaC, 0.2% by mass NbC, balance WC and An insert substrate for physical property evaluation (SNMN120408) made of (consisting of unavoidable impurities) is set in the CVD furnace 1 shown in FIG. 8, and the temperature inside the CVD furnace 1 is raised to 900 ° C. while flowing _{H 2 gas.} After that, at 900 ° C and 12 kPa, a _{raw material gas consisting of 82.0% by mass of H 2} gas, 18.5% by mass of N ₂ gas, and 1.5% by mass of TiCl ₄ gas was put into the CVD furnace 1 at a flow rate of 45 L / min. A titanium nitride layer (underlayer) having a thickness of 0.3 μm was formed by a flow and a chemical vapor deposition method.

(2) Formation of titanium nitride aluminum film After the formation of the base layer, the pipe assembly 30 shown in FIG. 9 rotating at a speed of 2 rpm while maintaining the temperature and pressure in the CVD furnace 1 at 800 ° C. and 4 kPa. In the CVD furnace 1, the first nozzles 11a, 11a of the first pipes 11, 11 to 0.33% by volume TiCl ₄ gas, 0.72% by volume AlCl ₃ gas, 43.02% by volume H ₂ gas, and 15.37. Introducing a mixed gas A consisting of% N ₂ gas, the second nozzle 12a of the second pipe 12, 12a to 1.38% by volume NH ₃ gas, 31.50% by volume H ₂ gas, and 7.68% by volume. A mixed gas B consisting of _{N 2 gas was introduced.} The total flow rate of the mixed gases A and B was 65 L / min. In this way, the hard film coating tool (insert) of the present invention in which the titanium nitride aluminum film was formed by the chemical vapor deposition method was produced. The width W of the cutting edge portion 101 of the hard film coating tool was 90 μm. Of the formed titanium aluminum nitride film, the composition _{at position P 1 of the cutting edge titanium nitride aluminum film region is Ti 0.32} Al _0.16 N _{0.52 (atomic ratio), and the composition at position P 2} of the rake face titanium nitride aluminum film region. Was Ti _0.16 Al _0.35 N _0.49 (atomic ratio), and the _{composition at position P 3} of the _{flank titanium nitride aluminum film region was Ti 0.17} Al _0.33 N _0.50 (atomic ratio). The raw material gas composition of the titanium nitride aluminum film is shown in Table 1 (a), and the film formation conditions are shown in Table 1 (b).

(3) Measurement of film thickness Two inserts (insert samples for evaluating physical properties) of Example 1 were prepared, and the SEM photograph (magnification of 5,000 times) of FIG. 6 (b) showing the vertical cross section of the cutting edge portion 101 for each sample. Therefore, the film thickness _{of the thinnest portion (position P 1} ) of the titanium nitride aluminum film 23 (cutting edge titanium nitride aluminum film region) in the cutting edge portion 101 was measured. The measured values of the film thickness at position P _{1 in the two samples were averaged to obtain the film thickness t 1} .

The measurement position _{of the film thickness t 2} of the rake face titanium nitride aluminum film region _{is the point P 2} on the rake face 102 1000 μm away from the _{position P 1} , and the measurement position of _{the film thickness t 3} of the flank surface titanium nitride aluminum film region is. It was _{point P 3} on the flank 103 1000 μm away from position P _1. From SEM photograph of FIG. 6 shows a longitudinal section of the rake face 102 near the P ₂ (b) (5,000 magnifications), the film thickness at the position P ₂ in the two samples were measured, and the film thickness t ₂ and the average value did. Similarly, the SEM photograph of FIG. 6 shows a longitudinal section of the P ₃ near the flank 103 (c) (5,000 magnifications) to measure the film thickness at the position P ₃ in the two samples, film thickness and the average value It was set to t ₃ . Table 3 shows the film thicknesses t ₁ , t ₂ , t ₃ , and the film thickness ratios t ₁ / t ₂ , t ₁ / t _3.

(4) Observation of the crystal structure of the titanium nitride aluminum film From Fig. 6 (b) and Fig. 6 (c), the rake face titanium nitride aluminum film region and the flank titanium nitride aluminum film region are both substantially uniform columnar crystal grains. It can be seen that it consists of polycrystals. From FIG. 6 (a), it can be seen that the morphology of the columnar crystal grains of the cutting edge portion 101 has a substantially uniform columnar crystal structure except for the vicinity _{of the film thickness t 1.}

(5) Measurement of crystal structure
(a) TEM sample For observation of TEM (field emission transmission electron microscope JEM-2100 manufactured by JEOL Ltd.) with the longitudinal fracture surface 115 exposed as shown in Fig. 4 (b) by polishing, Ar ion milling, etc. A sample was prepared.

(b) Nanobeam diffraction (NAD)
Nanobeam diffraction (NAD) was performed on the cutting edge 101 (position P ₁ ), rake face 102 (position P ₂ ), and flank 103 (position P ₃ ) of the observation sample using JEM-2100 under the following conditions. ) Was performed. As a result, it was found that the cutting edge titanium nitride aluminum film region, the rake face titanium nitride aluminum film region, and the flank surface titanium nitride aluminum film region all consist of a single structure of fcc.
Acceleration voltage: 200 kV
Camera length: 50 cm
Analysis area: 1 nm in diameter

(6) Measurement of composition of titanium aluminum nitride film The composition of titanium nitride aluminum film is analyzed using an electron probe microanalyzer (EPMA, JXA-8500F manufactured by JEOL Ltd.) with an acceleration voltage of 10 kV and an irradiation current of 0.05. The procedure was performed under the conditions of A and a beam diameter of 0.5 μm. FIG. 7 shows each range of the cutting edge portion 101, the rake face 102, and the flank surface 103, as well as the positions of each composition analysis by EPMA.

(a) Composition on the rake face side In the vertical cross section of the above observation sample, as shown in FIG. 7, _{the surface position R 20} to 20 μm above the rake face from _{the surface position P 1 of the thinnest part of the cutting edge 101.} R _500, and the surface position R ₅₀₀ to R ₈₀₀ of 50μm intervals, and analyzing compositions on the surface position R _1000. The measurement results are shown in Table 4. Figure 19 shows the distribution of the atomic ratios of Ti and Al at _{the surface positions R 20 to} R ₁₀₀₀ of the rake face titanium nitride aluminum film region. The horizontal axis in FIG. 19 shows the distance (μm) between the _{surface position P 1 and the measurement position.}

(b) Composition on the flank side In the vertical cross section of the above observation sample, as shown in FIG. 7, _{the surface position F 20} to 20 μm above the flank surface from _{the surface position P 1 of the thinnest part of the cutting edge portion 101.} Composition analysis was performed at F ₅₀₀ , surface positions F _{500 to} F _{800 at} intervals of 50 μm, and surface positions F _1000. The measurement results are shown in Table 5. Figure 20 shows the distribution of the atomic ratios of Ti and Al at _{the surface positions F 20 to} F ₁₀₀₀ of the flank titanium nitride aluminum film region. The horizontal axis in FIG. 20 shows the distance (μm) between the _{surface position P 1 and the measurement position.}

(c) Composition in the film thickness direction In the vertical cross section of the above observation sample, as shown in FIG. 7, each surface position P ₁ , R ₃₈₀ , R ₄₀₀ , R ₁₀₀₀ , F ₃₆₀ , F ₃₈₀ , F ₄₀₀ , F _1000. The composition of the titanium nitride aluminum film 23 was analyzed at _{the deep positions S, SR 380} , SR ₄₀₀ , SR ₁₀₀₀ , SF ₃₆₀ , SF ₃₈₀ , SF ₄₀₀ , and SF ₁₀₀₀ near the base layer 22 corresponding to the above. The measurement results are shown in Table 6. The deep position in the vicinity of the base layer 22 corresponding to the surface position means a position in the titanium nitride aluminum film 23 in the vicinity of the point where the perpendicular line extending from the surface position intersects the base layer 22.

(7) Performance evaluation The above insert 10 is attached to the tip of the replaceable cutting edge rotary tool (A45E-4160R) 50 shown in Fig. 16 with a wedge screw (not shown), and the tool life and tool life are as follows. The presence or absence of defects (chipping) was measured. The tool life was defined as the total cutting length (m) when the wear width of the titanium nitride aluminum film on the flank was observed with an optical microscope and the maximum wear width of the flank exceeded 0.25 mm. The presence or absence of defects (chipping) was determined by observing the optical microscope to determine whether or not minute chipping of 10 μm or more was generated in the cutting edge portion. The results are shown in Table 3.
Work Material: SCM440 with Hardness 32 HRC
Processing method: Milling Insert shape: SEE42EN-C9
Cutting speed: 200 m / min Rotation speed: 398 rpm
Feed per blade: 0.15 mm / tooth
Feed rate: 59.7 mm / min Axial depth of cut: 1.0 mm
Radial depth of cut: 100 mm
Cutting method: Wet cutting with a single blade

Examples 2 to 13
In Example 2, the TiCl ₄ gas of the mixed gas A was increased to 0.50% by volume, and the H ₂ gas was reduced to 42.85% by volume. In Examples 3 to 5, the volume ratio of the mixed gas A (TiCl ₄ / AlCl ₃ ) was changed in the range of 0.26 to 0.64. In License 6, the volume ratio of mixed gas A (TiCl ₄ / AlCl ₃ ) was fixed at 0.45, and the NH ₃ gas of mixed gas B was reduced to 1.00% by volume. In License 7, the volume ratio of mixed gas A (TiCl ₄ / AlCl ₃ ) was fixed at 0.46, and the NH ₃ gas of mixed gas B was increased to 1.78% by volume. In the royalty 8, the volume ratio of the mixed gas A (TiCl ₄ / AlCl ₃ ) is fixed at 0.46, _{the volume% of the N 2} gas of the mixed gas A and B is increased, and the volume% of the H ₂ gas of the mixed gas A is increased. Was reduced. In the royalty 9, the volume ratio of the mixed gas A (TiCl ₄ / AlCl ₃ ) is fixed at 0.46, _{the volume% of the N 2} gas of the mixed gas A and B is reduced, and the volume% of the H ₂ gas of the mixed gas A is reduced. Was increased. In Examples 10 and 11, the film formation pressure was changed to 3 kPa and 6 kPa. In Examples 12 and 13, the film formation temperature was changed to 750 ° C and 850 ° C. A hard film coating tool (insert) was prepared in the same manner as in Example 1 except that the raw material gas composition and film thickness conditions of the titanium nitride aluminum film were changed as shown in Table 1, and the positions P ₁ and P were changed. _2, the composition of the titanium aluminum nitride coating at P _3, the film thickness t _1, t _2, t _3, the film thickness ratio _{t 1 / t 2, t 1} / t 3, to evaluate the presence or absence of the tool life, and defects. The results are shown in Tables 2 (a) to 2 (c) and Table 3.

Example 14
A hard film-covered tool (insert) was manufactured in the same manner as in Example 1 except that a shelf without a through hole was used instead of the shelf 4 having a through hole 4a shown in FIG. 12, and each position P ₁ , P ₂ , P _3, the composition of the titanium nitride aluminum film, the film thickness t ₁ , t ₂ , t ₃ , the film thickness ratio t ₁ / t ₂ , t ₁ / t ₃ , the tool life, and the presence or absence of defects were evaluated. .. The results are shown in Tables 2 (a) to 2 (c) and Table 3.

Example 15
A titanium nitride layer (base layer) having a thickness of 0.3 μm was formed on the same substrate as in Example 1 as in Example 1. After forming the base layer, the mixed gas A is introduced into the CVD furnace 1 from the second nozzles 12a and 12a of the second pipe 12 using the pipe assembly 30 shown in FIG. 9, and the first pipe 11, The hard film coating tool (insert) of the present invention in which the titanium aluminum nitride film was formed by the chemical vapor deposition method was produced in the same manner as in Example 1 except that the mixed gas B was introduced from the first nozzles 11a and 11a of 11. Composition of titanium nitride aluminum film at positions P ₁ , P ₂ , and P _{3 , film thickness t 1} , t ₂ , t ₃ , film thickness ratio t ₁ / t ₂ , t ₁ / t ₃ , tool life, and presence / absence of defects Was evaluated. The results are shown in Tables 2 (a) to 2 (c) and Table 3.

Comparative example 1
A hard film thickness coating tool (insert) was manufactured in the same manner as in Example 1 except that the volume ratio (TiCl ₄ / AlCl ₃ ) of the mixed gas A was set to 1.30, and titanium nitride at _{each positions P 1} , P ₂ , and P _{3 was produced.} The composition of the aluminum film, the film thickness t ₁ , t ₂ , t ₃ , the film thickness ratio t ₁ / t ₂ , t ₁ / t ₃ , the tool life, and the presence or absence of defects were evaluated. The results are shown in Tables 2 (a) to 2 (c) and Table 3.

Conventional example 1
The CVD furnace 100 shown in FIG. 17 was used to form the titanium nitride aluminum film. The CVD furnace 100 comprises a pipe 110 having the nozzle 110a shown in FIG. 18 instead of the pipe assembly 30, and the shelf 4'has no through holes. Using such a CVD furnace 100, after forming the base layer in the same manner as in Example 1, 0.33% by volume of TiCl ₄ gas and 0.25% by volume of AlCl ₃ gas from the nozzle 110a at a temperature of 800 ° C. and a pressure of 4 kPa. , 74.99% by volume H ₂ gas, 23.05% by volume N ₂ gas, and 1.38% by volume NH ₃ gas, except that only mixed gas A was flowed into the CVD furnace 100 at a flow rate of 65.08 L / min. A hard film coating tool (insert) coated with a titanium nitride aluminum film was prepared and evaluated in the same manner as in Example 1. The results are shown in Tables 2 and 3.

_{For the inserts of Examples 6 and 7, EPMA analysis was performed from the surface position P 1} to the surface positions R ₁₀₀₀ and F _{1000 of the} titanium nitride aluminum film 23 in the same manner as in Example 1, and the Ti-rich rake face titanium nitride aluminum film region was performed. 102 _Ti inner edge position (cutting edge titanium nitride aluminum film region 101 _Ti from the thinnest part to width W ₂ position), and Ti rich flank titanium nitride aluminum film area 103 _Ti lower end position (cutting edge titanium nitride aluminum film) _{The position of the width W 3} from the thinnest part of the film region 101 _Ti ) was identified, and the film composition at those positions was measured. The results are shown in Table 7 (a) and Table 7 (b).

注：(1) 混合ガスAのみを原料ガスとして使用した。
(2) TiCl₄とAlCl₃との体積比。

Note: (1) Only mixed gas A was used as the raw material gas.
(2) Volume ratio of _{TiCl 4} and AlCl _3.

注：(1) 混合ガスAのみを原料ガスとして使用し、図18のノズル110aから噴出させた。

Note: (1) Only the mixed gas A was used as the raw material gas, and the gas was ejected from the nozzle 110a in FIG.

注：(1) 表面位置P₁で測定した。
(2) 切れ刃部の中心位置の表面で測定した。

Note: (1) Measured at _{surface position P 1.}
(2) Measured on the surface at the center of the cutting edge.

注：(1) 表面位置P₂で測定した。
(2) 切れ刃部の中心から1000μｍ離れたすくい面の表面で測定した。

Note: (1) Measured at _{surface position P 2.}
(2) The measurement was performed on the surface of the rake face 1000 μm away from the center of the cutting edge.

注：(1) 表面位置P₃で測定した。
(2) 切れ刃部の中心から1000μｍ離れた逃げ面の表面で測定した。

Note: (1) was measured by a surface position P _3.
(2) The measurement was performed on the surface of the flank surface 1000 μm away from the center of the cutting edge.

注：(1) 工具寿命時における欠損（10μm以上の微小チッピング）。
(2) 切れ刃部の中心の膜厚をt₁とし、切れ刃部の中心から1000μｍ離れたすくい面及び逃げ面の膜厚をそれぞれt₂、t₃とした。

Note: (1) Defects at the end of tool life (small chipping of 10 μm or more).
(2) The film thickness at the center of the cutting edge was t _1, and the film thicknesses of the rake face and flank surface 1000 μm away from the center of the cutting edge were t ₂ and t ₃ , respectively.

注：(1) 切れ刃窒化チタンアルミニウム皮膜領域。
(2) Tiリッチなすくい面窒化チタンアルミニウム皮膜領域。
(3) Alリッチなすくい面窒化チタンアルミニウム皮膜領域。

Note: (1) Cutting edge titanium nitride aluminum film area.
(2) Ti-rich rake face Titanium nitride aluminum film area.
(3) Al-rich rake face Titanium nitride aluminum film area.

注：(1) 切れ刃窒化チタンアルミニウム皮膜領域。
(2) Tiリッチな逃げ面窒化チタンアルミニウム皮膜領域。
(3) Alリッチな逃げ面窒化チタンアルミニウム皮膜領域。

Note: (1) Cutting edge titanium nitride aluminum film area.
(2) Ti-rich flank titanium nitride aluminum film region.
(3) Al-rich flank titanium nitride aluminum film region.

注：(1) 切れ刃窒化チタンアルミニウム皮膜領域。
(2) Tiリッチなすくい面窒化チタンアルミニウム皮膜領域。
(3) Alリッチなすくい面窒化チタンアルミニウム皮膜領域。
(4) Tiリッチな逃げ面窒化チタンアルミニウム皮膜領域。
(5) Alリッチな逃げ面窒化チタンアルミニウム皮膜領域。

Note: (1) Cutting edge titanium nitride aluminum film area.
(2) Ti-rich rake face Titanium nitride aluminum film area.
(3) Al-rich rake face Titanium nitride aluminum film area.
(4) Ti-rich flank titanium nitride aluminum film region.
(5) Al-rich flank titanium nitride aluminum film region.

注：(1) Tiリッチなすくい面窒化チタンアルミニウム皮膜領域102_Tiの内端位置。

Note: (1) Ti rich rake face Titanium nitride aluminum film region 102 _Ti inner edge position.

注：(1) Tiリッチな逃げ面窒化チタンアルミニウム皮膜領域103_Tiの下端位置。

Note: (1) Ti rich flank Titanium nitride aluminum film region 103 _Ti lower end position.

As is clear from Tables 2 (a) to 2 (c), all of the titanium nitride aluminum films of Examples 1 to 15 have a Ti-rich composition at _{the position P 1 of the cutting edge portion 101, and the rake face 102.} And 103 flank positions P ₂ and P ₃ had an Al-rich composition. As is clear from Table 3, each titanium nitride aluminum film of Examples 1 to 15 has a film thickness t ₁ of 4.2 to 9.2 μm, a film thickness t ₂ of 7.2 to 14.5 μm, and a film thickness t of 7.1 to 14.2 μm. _3, the thickness ratio t ₁ / t ₂ of 0.44 to 0.82, and has a film thickness ratio t ₁ / t ₃ of 0.48 to 0.83, the thickness t ₁ of the cutting edge titanium aluminum nitride coating region rake surface titanium aluminum nitride The film thicknesses of the film region and flank titanium-aluminum nitride film region were smaller than _{t 2} and t _3. On the other hand, in the inserts of Comparative Example 1 and Conventional Example 1, the film thickness ratio t ₁ / t ₂ is 0.95 and 0.98, respectively, and the film thickness ratio t ₁ / t ₃ is 1.01 and 1.03, respectively, and the film thickness difference is almost the same. There wasn't.

As is clear from Table 3, the tool life of each of Examples 1 to 15 was 5 m or more in the cutting distance, and no defect occurred. On the other hand, the tool life of Comparative Example 1 and Conventional Example 1 was less than 1/2 of that of Examples 1 to 15, and a defect was observed. This is because a Ti-rich titanium aluminum nitride film having excellent fracture resistance is formed on the cutting edge of each of the inserts of Examples 1 to 15, and Al-rich nitride having excellent heat resistance is formed on the rake face and the flank surface. It is considered that this is because a titanium-aluminum film is formed. On the other hand, each of the inserts of Comparative Example 1 and Conventional Example 1 has a titanium aluminum nitride film having almost the same Al, Ti and N contents formed on the cutting edge portion, the rake face and the flank surface, so that the heat resistance and the heat resistance are improved. It had poor fracture resistance and a short life.

As shown in FIGS. 7, 19 and 4, in Example 1, the cutting edge titanium nitride aluminum film region 101 _Ti and the Ti-rich rake face titanium nitride aluminum film region 102 _Ti are Ti-rich with similar atomic ratios. It had a composition, and the Ti content sharply decreased and the Al content sharply increased from the vicinity of the position R _{380, which was 380 μm away from the position P 1 , and the Al-rich rake face titanium nitride aluminum film region 102 Al} was formed. As shown in Table 4, the N content remained almost unchanged _{from position P 1} to position R _1000.

As shown in FIGS. 7, 20 and Table 5, in Example 1, the cutting edge titanium nitride aluminum film region 101 _Ti and the Ti-rich flank titanium nitride aluminum film region 103 _Ti are Ti-rich with similar atomic ratios. It had a composition, and the Ti content decreased sharply and the Al content increased sharply from the vicinity of _{F 360, which} was 360 μm away from _{the position P 1, and an Al-rich flank titanium nitride aluminum film region 103 Al} was formed. As shown in Table 5, the Ti content and Al content are located near the position F ₃₈₀ between the Ti-rich flank titanium nitride aluminum film region 103 _Ti and the Al-rich flank titanium nitride aluminum film region 103 _Al. Almost the same boundary portion 120 was formed. The N content remained almost unchanged from position P ₁ to position F _1000.

As shown in Table 7 (a), the inner end position of the Ti-rich rake face titanium nitride aluminum film region 102 _{Ti is R 180 in Example 6 and R 600} in Example 7, both of which are inside the rake face 102. Was there. As shown in Table 7 (b), the lower end position of the Ti-rich flank titanium nitride aluminum film region 103 _{Ti is F 160 in Example 6 and R 550} in Example 7, both of which are within the flank. there were.

_{The total amount of (TiCl 4} gas + AlCl ₃ gas + NH ₃ gas) in the raw material gas of each example used was 2.43% by volume in Example 1, 1.90% by volume in Example 6, and 3.12% by volume in Example 7. there were. The NH ₃ gas content was 1.38% by volume in Example 1, 1.00% by volume in Example 6, and 1.78% by volume in Example 7. From the comparison of these raw material gas compositions with R ₃₈₀ and F _{360 of Example 1, R 180} and F ₁₆₀ of Example 6, and R ₆₀₀ and F _{550 of Example 7, (TiCl 4} gas) in the raw material gas. It can be seen that the larger the total amount of + AlCl ₃ gas + NH _{3 gas), especially the higher the ratio of NH 3} gas in the raw material gas, the larger the Ti-rich portion expands on the rake face 102 and the flank surface 103.

As is clear from Table 6 and FIG. 7, in the titanium nitride aluminum film 23 of Example 1, positions P ₁ and S, positions R ₃₈₀ and SR ₃₈₀ , positions R ₄₀₀ and SR ₄₀₀ , positions R ₁₀₀₀ and SR ₁₀₀₀ , and positions The _{compositions of F 360} and SF ₃₆₀ , positions F ₃₈₀ and SF ₃₈₀ , positions F ₄₀₀ and SF ₄₀₀ , and positions F ₁₀₀₀ and SF ₁₀₀₀ were all almost the same, and the composition variation in the film thickness direction was very small.

Comparing the SEM photograph of FIG. 5 with the SEM photograph of FIG. 21, the titanium nitride aluminum film of Example 1 has a cutting edge thinner than the rake face and the flank surface, whereas the titanium aluminum nitride film of Conventional Example 1 is cut. It can be seen that the blade portion, the rake surface, and the flank surface have almost the same film thickness.

In the titanium nitride aluminum film 23 of Example 1, the Ti-rich portion 102 _Ti and the Al-rich portion 102 _Al are in contact with each other on _{the rake face 102, and the Ti-rich portion 103 Ti} and the Al-rich portion 103 _{Al on the flank surface 103.} A boundary portion having substantially the same Ti content and Al content was formed between the two, but the hard film coating tool of the present invention is not particularly limited to this, and even if the boundary portion is formed on the rake face 102. It may be good, and the flank 103 may have no boundary.

In all of the above examples, the cutting edge portion is not subjected to the cutting edge treatment, but even when the cutting edge portion is subjected to the cutting edge treatment, the advantageous effect of the present invention can be achieved, and heat resistance and fracture resistance can be improved. A hard film coating tool having an excellent titanium nitride aluminum film can be obtained.

1: CVD furnace
2: Chamber
3: Heater
4: Shelf
4a, 4b, 4c: Through hole
4': Shelf without through holes
5: Reaction vessel
5a: Cloaca
6: Partition plate
10: Insert
11: First pipe
11a: Nozzle of the first pipe
12: Second pipe
12a: Nozzle of the second pipe
13: Discharge pipe
21: Hypokeimenon
22: Base layer
23: Titanium nitride aluminum film
30: First pipe assembly
33: Second pipe assembly
36: Third pipe assembly
40: Central opening of the shelf
50: Rotating tool with replaceable cutting edge
101: Cutting edge
101a: Corner cutting edge
101b: Edge cutting edge
102: Scoop surface
102 _Ti : Ti rich rake face titanium nitride aluminum film area
102 _Al : Al-rich rake face titanium nitride aluminum film region
103: Escape surface
103 _Ti : Ti rich flank titanium nitride aluminum film region
103 _Al : Al-rich flank titanium nitride aluminum film region
103a': Corner side
103b': Side side
115: Longitudinal section
120: Boundary
P ₁ , P ₂ , P ₃ : Measurement position
Q ₁ , Q ₂ , R ₁ , R ₂ : Inflection points on the rake face and flank surface of the titanium nitride aluminum film
W: Width of cutting edge
W ₂ : Ti-rich rake face Titanium nitride Aluminum film region width
W ₃ : Ti-rich flank titanium nitride aluminum film region width

Claims (13)

A hard film coating tool formed by forming a titanium nitride aluminum film on a substrate, which has a cutting edge portion, a rake surface, and a flank surface.
The titanium nitride aluminum film is a chemical vapor deposition film.
Of the cutting edge portion, the rake face, and the flank surface, the cutting edge portion has the thinnest portion of the titanium nitride aluminum film, and the titanium nitride aluminum film on the cutting edge portion is (Tix ₁ Aly ₁ ) Nz. ₁ (However, x ₁ , y ₁ and z ₁ are atomic ratios, respectively, and are numbers that satisfy _{0.26 ≤ x 1} ≤ 0.4, 0.1 ≤ y ₁ ≤ 0.24, and x ₁ + y ₁ + z _{1 = 1.)} Has a Ti-rich composition represented
At the rake face and the flank, respectively, at least 1000 μm away from the thinnest portion of the titanium nitride aluminum film on the cutting edge, the titanium nitride aluminum film is (Tix ₂ Aly ₂ ) Nz ₂ (where x _2). , Y ₂ and z ₂ are atomic ratios, respectively, and are Al-rich numbers that satisfy _{0.06 ≤ x 2} ≤ 0.23, 0.25 ≤ y ₂ ≤ 0.45, and x ₂ + y ₂ + z _{2 = 1.} A hard film coating tool characterized by having a composition. In the hard coating tool according to claim 1, x ₁ and y ₁ satisfy the atomic ratios of 0.28 ≤ x ₁ ≤ 0.40 and 0.10 ≤ y _{1 ≤ 0.2 2 , respectively, and x 2} and y 2 each satisfy the atomic ratio of 0.08. A hard film characterized in that ≤ x ₂ ≤ 0.22 and 0.26 ≤ y ₂ ≤ 0.43 are satisfied, _{the difference between x 1} and x ₂ is 0.10 or more, and the difference between y ₂ and y _{1 is 0.10 or more.} Covering tool. The hard film coating tool according to claim 1 or 2, wherein a region of the titanium aluminum nitride film on the rake face and the flank surface adjacent to the cutting edge portion has a Ti-rich composition. Hard film coating tool. In the hard film coating tool according to claim 3, the region where the titanium nitride aluminum film on the rake face has a Ti-rich composition is from the boundary between the cutting edge portion and the rake face, and the cutting edge portion is described. The region existing in a range of 180 to 600 μm away from the thinnest portion of the titanium nitride aluminum film and having a Ti-rich composition of the titanium aluminum nitride film on the flank is the cutting edge portion and the cutting edge portion. A hard film coating tool characterized in that it exists in a range from the boundary of the flank surface to a position 160 μm to 550 μm away from the thinnest portion of the titanium nitride aluminum film on the cutting edge portion. The hard film coating tool according to any one of claims 1 to 4, wherein the titanium nitride aluminum film mainly has a columnar crystal structure. The hard film coating tool according to any one of claims 1 to 5, wherein z ₁ satisfies an atomic ratio of 0.64 to 0.36 and z ₂ satisfies an atomic ratio of 0.69 to 0.32. In the hard film coating tool according to any one of claims 1 to 6.
A base layer is provided between the substrate and the titanium nitride aluminum film.
A hard film coating tool characterized in that the base layer is a single layer film or a laminated film composed of at least one of titanium carbonitride, titanium nitride, and zirconium titanium nitride, and has an fcc structure. A method for manufacturing a hard film coating tool according to any one of claims 1 to 7 by a chemical vapor deposition method.
Taking the total of TiCl ₄ gas, AlCl ₃ gas, NH ₃ gas, N ₂ gas and H ₂ gas as 100% by volume, 0.1 to 0.8% by volume of TiCl ₄ gas, 0.4 to 1.2% by volume of AlCl ₃ gas, 4.0 to 23.5. A mixed gas A consisting of% by volume N ₂ gas and the balance H ₂ gas and having a volume ratio of TiCl _{4 gas to AlCl 3 gas (TiCl 4} / AlCl ₃ ) of 0.3 to 0.7, and 0.7 to 1.9% by volume. A method characterized by forming the titanium nitride aluminum film by supplying a raw material gas composed of NH ₃ gas, 3 to 16.5% by volume N ₂ gas, and _{mixed gas B composed of the balance H 2 gas.} In the method for manufacturing a hard film coating tool according to claim 8,
Using a chemical vapor deposition apparatus equipped with first and second pipes that rotate around the axis O,
The first pipe has a first nozzle
The second pipe has a second nozzle
_{The distance H 1} between the spout of the first nozzle and the rotating shaft O is made longer than _{the distance H 2} between the spout of the second nozzle and the rotating shaft O.
A method characterized in that the mixed gas A is ejected from the first nozzle and the mixed gas B is ejected from the second nozzle. In the method for manufacturing a hard film coating tool according to claim 8,
Using a chemical vapor deposition apparatus equipped with first and second pipes that rotate around the axis O,
The first pipe has a first nozzle
The second pipe has a second nozzle
_{The distance H 1} between the spout of the first nozzle and the rotating shaft O is made longer than _{the distance H 2} between the spout of the second nozzle and the rotating shaft O.
A method characterized in that the mixed gas A is ejected from the second nozzle and the mixed gas B is ejected from the first nozzle. In the method for manufacturing a hard film coating tool according to claim 9 or 10.
The chemical vapor deposition apparatus is provided around the first and second pipes between a plurality of shelves on which the substrate is placed and adjacent shelves, respectively, in order to block the flow of the raw material gas. Has a partition plate and
The first and second nozzles are provided between each shelf and a partition plate located above the shelf and at the upper part of the uppermost shelf, respectively.
A method characterized in that at least one through hole is provided around the substrate in the shelf, and the raw material gas ejected from the first and second nozzles passes through the through hole. In the method for manufacturing a hard film coating tool according to any one of claims 8 to 11, the ratio (H ₁ / H _{2 ) of the distance H 1} to the distance H ₂ should be within the range of 1.5 to 3. How to feature. A method according to any one of claims 8 to 12, wherein a film forming pressure of 3 to 6 kPa and a film forming temperature of 750 to 830 ° C. are used in the method for manufacturing a hard film coating tool.

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