WO2023008189A1

WO2023008189A1 - Coated tool and cutting tool

Info

Publication number: WO2023008189A1
Application number: PCT/JP2022/027485
Authority: WO
Inventors: 啓吉見
Original assignee: 京セラ株式会社
Priority date: 2021-07-30
Filing date: 2022-07-12
Publication date: 2023-02-02
Also published as: JPWO2023008189A1; CN117529381A

Abstract

A coated tool according to the present disclosure comprises a base material, and a coating layer that is positioned on the base material. The coating layer comprises a first coating layer that contains Al, Cr, Si and N. The first coating layer comprises first layers and second layers, which are alternately arranged in the thickness direction. The first layers and the second layers contain Al, Cr, Si and N. The Al content in the first layers is expressed as the first Al content; the Cr content in the first layers is expressed as the first Cr content; the Si content in the first layers is expressed as the first Si content; the Al content in the second layers is expressed as the second Al content; the Cr content in the second layers is expressed as the second Cr content; and the Si content in the second layers is expressed as the second Si content. In this case, the first Al content is higher than the second Al content; the first Cr content is lower than the second Cr content; and the first Si content is higher than the second Si content.

Description

coated and cutting tools

The present disclosure relates to coated tools and cutting tools.

2. Description of the Related Art As a tool used for cutting such as turning and milling, there is known a coated tool whose wear resistance is improved by coating the surface of a substrate made of cemented carbide, cermet, ceramics, or the like with a coating layer. there is

Japanese Patent Application Laid-Open No. 2004-50381 JP 2018-30212 A

A coated tool according to one aspect of the present disclosure has a substrate and a coating layer located on the substrate. The coating layer has a first coating layer containing Al, Cr, Si and N. The first coating layer has first layers and second layers alternately positioned in the thickness direction. The first layer and the second layer contain Al, Cr, Si and N. The Al content in the first layer is the first Al content, the Cr content in the first layer is the first Cr content, the Si content in the first layer is the first Si content, and the Al content in the second layer is the second Al The Cr content in the second layer is defined as the second Cr content, and the Si content in the second layer is defined as the second Si content. In this case, the first Al content is greater than the second Al content, the first Cr content is less than the second Cr content, and the first Si content is greater than the second Si content.

1 is a perspective view showing an example of a coated tool according to an embodiment; FIG. FIG. 2 is a side cross-sectional view showing an example of the coated tool according to the embodiment. FIG. 3 is a cross-sectional view showing an example of a coating layer according to the embodiment; 4 is a schematic enlarged view of the H portion shown in FIG. 3. FIG. FIG. 5 is a schematic diagram for explaining the Al content, Cr content and Si content of the first layer and the second layer. FIG. 6 is a front view showing an example of the cutting tool according to the embodiment; FIG. 7 shows sample no. 1 to No. 16 is a table summarizing the manufacturing conditions of the first coating layer for No. 16. FIG. 8 shows sample no. 1 to No. 16 is a table summarizing the measurement results of the composition of the first coating layer and the metal content of No. 16. FIG. FIG. 9 shows sample no. 1 to No. 16 is a table summarizing the wear test results for No. 16; FIG. 10 is a scanning transmission electron microscope image of the first coating layer according to the embodiment. FIG. 11 is a graph showing changes in Al content, Cr content, Si content and N content in the stacking direction of the first layer and the second layer.

Hereinafter, embodiments for carrying out the coated tool and cutting tool according to the present disclosure (hereinafter referred to as "embodiments") will be described in detail with reference to the drawings. It should be noted that this embodiment does not limit the coated tools and cutting tools according to the present disclosure. Further, each embodiment can be appropriately combined within a range that does not contradict the processing contents. Also, in each of the following embodiments, the same parts are denoted by the same reference numerals, and overlapping descriptions are omitted.

Further, in the embodiments described below, expressions such as "constant", "perpendicular", "perpendicular" or "parallel" may be used, but these expressions are strictly "constant", "perpendicular", " It does not have to be "perpendicular" or "parallel". That is, each of the expressions described above allows deviations in, for example, manufacturing accuracy and installation accuracy.

The conventional technology described above has room for further improvement in terms of improving chipping resistance.

<Coated tool>
1 is a perspective view showing an example of a coated tool according to an embodiment; FIG. Moreover, FIG. 2 is a sectional side view which shows an example of the coated tool 1 which concerns on embodiment. As shown in FIG. 1, the coated tool 1 according to the embodiment has a tip body 2. As shown in FIG.

(Chip body 2)
Chip body 2 has, for example, a hexahedral shape in which the upper and lower surfaces (surfaces intersecting the Z-axis shown in FIG. 1) are parallelograms.

One corner of the tip body 2 functions as a cutting edge. The cutting edge has a first surface (eg, top surface) and a second surface (eg, side surface) contiguous with the first surface. In the embodiment, the first surface functions as a "rake surface" for scooping chips generated by cutting, and the second surface functions as a "flank surface". A cutting edge is positioned on at least a part of the ridge line where the first surface and the second surface intersect, and the coated tool 1 cuts the work material by bringing the cutting edge into contact with the work material.

A through hole 5 penetrating vertically through the chip body 2 is located in the center of the chip body 2 . A screw 75 for attaching the coated tool 1 to a holder 70, which will be described later, is inserted into the through hole 5 (see FIG. 6).

As shown in FIG. 2, the chip body 2 has a substrate 10 and a coating layer 20. As shown in FIG.

(Substrate 10)
Substrate 10 is made of cemented carbide, for example. Cemented carbide contains W (tungsten), specifically WC (tungsten carbide). Moreover, the cemented carbide may contain Ni (nickel) or Co (cobalt). Specifically, the substrate 10 is made of a WC-based cemented carbide containing WC particles as a hard phase component and Co as a main component of a binder phase.

Also, the substrate 10 may be made of cermet. The cermet contains, for example, Ti (titanium), specifically TiC (titanium carbide) or TiN (titanium nitride). Moreover, the cermet may contain Ni or Co.

Further, the base 10 may be formed of a cubic boron nitride sintered body containing cubic boron nitride (cBN) particles. Substrate 10 is not limited to cubic boron nitride (cBN) particles, but may contain particles such as hexagonal boron nitride (hBN), rhombohedral boron nitride (rBN), wurtzite boron nitride (wBN), and the like. .

(Coating layer 20)
The coating layer 20 is coated on the substrate 10 for the purpose of improving wear resistance, heat resistance, etc. of the substrate 10, for example. In the example of FIG. 2, the coating layer 20 covers the substrate 10 entirely. The coating layer 20 may be positioned at least on the substrate 10 . When the coating layer 20 is located on the first surface (here, the upper surface) of the substrate 10, the first surface has high wear resistance and heat resistance. When the coating layer 20 is located on the second surface (here, side surface) of the substrate 10, the second surface has high wear resistance and heat resistance.

Here, a specific configuration of the coating layer 20 will be described with reference to FIGS. 3 and 4. FIG. FIG. 3 is a cross-sectional view showing an example of the coating layer 20 according to the embodiment. Moreover, FIG. 4 is a model enlarged view of the H section shown in FIG.

As shown in FIG. 3 , the covering layer 20 has a first covering layer 23 positioned on the intermediate layer 22 and a second covering layer 24 positioned on the first covering layer 23 .

(First covering layer 23)
The first coating layer 23 is selected from the group consisting of at least one element selected from the group consisting of Al, Group 5 elements, Group 6 elements and Group 4 elements excluding Ti, and C and N. It has at least one element, Si and Cr.

Specifically, the first coating layer 23 contains Al, Cr, Si, and N. That is, the first coating layer 23 may be an AlCrSiN layer containing AlCrSiN, which is a nitride of Al, Cr and Si. The notation "AlCrSiN" means that Al, Cr, Si and N are present in an arbitrary ratio, and the ratio of Al, Cr, Si and N is not necessarily 1:1:1:1. It is not meant to exist.

By positioning the first covering layer 23 containing the metal (eg, Si) contained in the intermediate layer 22 on the intermediate layer 22 in this way, the adhesion between the intermediate layer 22 and the covering layer 20 is high. This makes it difficult for the covering layer 20 to separate from the intermediate layer 22, so that the durability of the covering layer 20 is high.

As shown in FIG. 4, the first covering layer 23 has a plurality of first layers 23a and a plurality of second layers 23b. The first covering layer 23 has a striped configuration in which first layers 23a and second layers 23b are alternately laminated in the thickness direction. The first layer 23a is a layer in contact with the intermediate layer 22, and the second layer 23b is formed on the first layer 23a.

The thicknesses of the first layer 23a and the second layer 23b may each be 50 nm or less. Since the thin first layer 23a and the second layer 23b have a small residual stress and are less likely to be peeled off or cracked, the durability of the coating layer 20 is increased.

The second coating layer 24 may contain Ti, Si and N. That is, the second coating layer 24 may be a nitride layer (TiSiN layer) containing Ti and Si. Note that the expression “TiSiN layer” means that Ti, Si, and N are present in an arbitrary ratio, and that Ti, Si, and N are necessarily present in a ratio of 1:1:1. not something to do.

Thereby, for example, when the coefficient of friction of the second coating layer 24 is low, the adhesion resistance of the coated tool 1 can be improved. Moreover, for example, when the hardness of the second coating layer 24 is high, the wear resistance of the coated tool 1 can be improved. Further, for example, when the oxidation initiation temperature of the second coating layer 24 is high, the oxidation resistance of the coated tool 1 can be improved.

FIG. 5 is a schematic diagram for explaining the Al content, Cr content and Si content of the first layer 23a and the second layer 23b.

The first layer 23a and the second layer 23b contain Al, Cr, Si and N. Here, the Al content in the first layer 23a is referred to as the first Al content, the Cr content in the first layer 23a is referred to as the first Cr content, and the Si content in the first layer 23a is referred to as the first Si content. Also, the Al content in the second layer 23b is referred to as the second Al content, the Cr content in the second layer 23b is referred to as the second Cr content, and the Si content in the second layer 23b is referred to as the second Si content.

In this case, the first Al content may be greater than the second Al content, the first Cr content may be less than the second Cr content, and the first Si content may be greater than the second Si content.

The coated tool 1 having the first coating layer 23 having such a configuration has high hardness and excellent chipping resistance.

Also, the total amount of Al, Cr, and Si in the metal elements contained in the first coating layer 23 may be 98 atomic % or more.

The coated tool 1 having the first coating layer 23 having such a configuration has higher hardness and excellent chipping resistance.

Also, the ratio of Al to the metal elements of the first coating layer 23 may be 38 atomic % or more and 55 atomic % or less. The ratio of Cr to the metal elements of the first coating layer 23 may be 33 atomic % or more and 48 atomic % or less. The ratio of Si to the metal elements of the first coating layer 23 may be 4 atomic % or more and 15 atomic % or less.

The coated tool 1 having the first coating layer 23 having such a configuration has improved oxidation resistance and excellent wear resistance.

Also, the difference between the first Al content and the second Al content may be 1 atomic % or more and 9 atomic % or less.

The coated tool 1 having the first coating layer 23 having such a structure maintains high oxidation resistance and high hardness, relieves the stress inside the coating layer, and has excellent wear resistance.

The coated tool 1 having the first coating layer 23 having such a configuration has particularly high hardness.

Also, the difference between the first Cr content and the second Cr content may be 1 atomic % or more and 12 atomic % or less.

The coated tool 1 having the first coating layer 23 having such a configuration has even better wear resistance.

The coated tool 1 having the first coating layer 23 having such a configuration is particularly excellent in chipping resistance.

Also, the difference between the first Si content and the second Si content may be 0.5 atomic % or more and 5 atomic % or less.

Also, the thickness of the first layer 23a and the second layer 23b may be 1 nm or more and 20 nm or less.

The coated tool 1 having the first coating layer 23 having such a configuration has excellent hardness and chipping resistance.

(Intermediate layer 22)
An intermediate layer 22 may be positioned between the substrate 10 and the covering layer 20 . Specifically, the intermediate layer 22 is in contact with the upper surface of the substrate 10 on one surface (here, the lower surface) and on the lower surface of the coating layer 20 (the first coating layer 23) on the other surface (here, the upper surface). touch.

The intermediate layer 22 has higher adhesion to the substrate 10 than the coating layer 20 does. Examples of metal elements having such properties include Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, Si, Y, and Ti. The intermediate layer 22 contains at least one metal element among the above metal elements. For example, intermediate layer 22 may contain Ti. Although Si is a metalloid element, metalloid elements are also included in metal elements in this specification.

When the intermediate layer 22 contains Ti, the content of Ti in the intermediate layer 22 may be 1.5 atomic % or more. For example, the content of Ti in intermediate layer 22 may be 2.0 atomic % or more.

The intermediate layer 22 may contain metal element components other than the above metal elements (Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, Si, Y, Ti). However, from the viewpoint of adhesion to the substrate 10, the intermediate layer 22 may contain at least 95 atomic percent of the above metal elements in total. More preferably, the intermediate layer 22 may contain the above metal elements in a total amount of 98 atomic % or more. The ratio of metal components in intermediate layer 22 can be identified by analysis using, for example, an EDS (energy dispersive X-ray spectroscope) attached to a STEM (scanning transmission electron microscope).

Thus, in the coated tool 1 according to the embodiment, by providing the intermediate layer 22 between the substrate 10 and the coating layer 20, which has higher wettability with the substrate 10 than the coating layer 20, the substrate 10 and the coating layer 20 can be improved. In addition, since the intermediate layer 22 has high adhesion to the covering layer 20 , the covering layer 20 is less likely to separate from the intermediate layer 22 .

Note that the thickness of the intermediate layer 22 may be, for example, 0.1 nm or more and less than 20.0 nm.

<Cutting tool>
Next, the configuration of a cutting tool provided with the above-described coated tool 1 will be described with reference to FIG. FIG. 6 is a front view showing an example of the cutting tool according to the embodiment;

As shown in FIG. 6, the cutting tool 100 according to the embodiment has a coated tool 1 and a holder 70 for fixing the coated tool 1. As shown in FIG.

The holder 70 is a rod-shaped member extending from a first end (upper end in FIG. 6) toward a second end (lower end in FIG. 6). The holder 70 is made of steel or cast iron, for example. In particular, among these members, it is preferable to use steel with high toughness.

The holder 70 has a pocket 73 at the end on the first end side. The pocket 73 is a portion to which the coated tool 1 is mounted, and has a seating surface that intersects with the rotational direction of the work material and a restraining side surface that is inclined with respect to the seating surface. The seating surface is provided with screw holes into which screws 75, which will be described later, are screwed.

The coated tool 1 is positioned in the pocket 73 of the holder 70 and attached to the holder 70 with screws 75 . That is, the screw 75 is inserted into the through hole 5 of the coated tool 1, and the tip of the screw 75 is inserted into the screw hole formed in the seating surface of the pocket 73 to screw the screw portions together. Thereby, the coated tool 1 is attached to the holder 70 so that the cutting edge portion protrudes outward from the holder 70 .

The embodiment exemplifies a cutting tool used for so-called turning. Turning includes, for example, inner diameter machining, outer diameter machining, and grooving. The cutting tools are not limited to those used for turning. For example, the coated tool 1 may be used as a cutting tool used for milling. Examples of cutting tools used for milling include flat milling cutters, face milling cutters, side milling cutters, grooving milling cutters, single-blade end mills, multiple-blade end mills, tapered blade end mills, ball end mills, and other end mills. .

(Production method)
Next, an example of a method for manufacturing the coated tool 1 according to this embodiment will be described. In addition, the manufacturing method of the coated tool by this indication is not limited to the following manufacturing method.

The coating layer may be formed, for example, by physical vapor deposition. Examples of physical vapor deposition include ion plating and sputtering. As an example, when the coating layer is produced by the ion plating method, the coating layer can be produced by the following method.

First, an example of a method for producing the first coating layer 23 by ion plating is shown. First, as an example, metal targets of Cr, Si and Al, composite alloy targets, or sintered targets are prepared.

Next, the target, which is a metal source, is vaporized and ionized by arc discharge, glow discharge, or the like. The ionized metal is reacted with a nitrogen source such as nitrogen (N ₂ ) gas, etc., and deposited on the surface of the substrate. An AlCrSiN layer can be formed by the above procedure.

In the above procedure, the temperature of the substrate is set to 500 to 600° C., the nitrogen gas pressure is set to 1.0 to 6.0 Pa, a DC bias voltage of −50 to −200 V is applied to the substrate, and the arc discharge current is set to 100 to 100. It may be 200A.

For the composition of the first coating layer, the voltage and current values during arc discharge and glow discharge applied to an aluminum metal target, a chromium metal target, an aluminum-silicon composite alloy target, and a chromium-silicon composite alloy target are determined for each target. can be adjusted by controlling each independently. The composition of the coating layer can also be adjusted by controlling the coating time and atmospheric gas pressure. In one embodiment, the amount of ionization of the target metal can be changed by changing the voltage/current values during arc discharge/glow discharge. In addition, by periodically changing the current value during arc discharge/glow discharge for each target, the ionization amount of the target metal can be changed periodically. By periodically changing the current value during the arc discharge/glow discharge of the target at intervals of 0.01 to 0.5 min, the ionization amount of the target metal can be changed periodically. Thereby, in the thickness direction of the coating layer, the content ratio of each metal element can be changed at each period.

When performing the above procedure, the composition of Al, Si, and Cr is changed so that the amounts of Al and Si are reduced and the amounts of Cr are increased, and then the amounts of Al and Si are increased. By varying the composition of Al, Si, and Cr, it is possible to produce a first coating layer having a first layer and a second layer, such that the amount of Cr is reduced.

Next, an example of a method for manufacturing the second coating layer, which is a TiSiN layer, will be described.

Similarly to the first coating layer, the second coating layer may also be formed by physical vapor deposition. As an example, first, a Ti metal target and a Ti—Si composite alloy target are prepared. Then, the second coating layer having a striped structure can be produced by independently controlling the voltage/current values applied to each prepared target during arc discharge/glow discharge for each target.

In the above procedure, the temperature of the substrate is set to 500 to 600° C., the nitrogen gas pressure is set to 1.0 to 6.0 Pa, a DC bias voltage of −50 to −200 V is applied to the substrate, and the arc discharge current is set to 100 to 100. 200A and the arc current change period may be 0.01 to 0.5 min.

Examples of the present disclosure will be specifically described below. Note that the present disclosure is not limited to the examples shown below.

A coated tool was produced by forming a first coating layer on a substrate made of WC. 1 to No. 16. FIG. 7 shows sample no. 1 to No. 16 is a table summarizing the manufacturing conditions of the first coating layer for No. 16. In addition, sample no. 1 to No. Sample No. 16 out of 16 1 to No. 11, No. 14 to No. 16 corresponds to an embodiment of the present disclosure. Moreover, sample no. 1 to No. Sample No. 16 out of 16 12, No. 13 corresponds to a comparative example.

First, various metal targets, composite alloy targets, or sintered targets were prepared. Specifically, three types of targets (first to third targets) were prepared. Next, the target, which is a metal source, was vaporized and ionized by arc discharge, glow discharge, or the like. Next, the ionized metal was vapor-deposited on the surface of the substrate while reacting with nitrogen (N ₂ ) gas as a nitrogen source. A first coating layer was formed on the substrate by the above procedure. In addition, the current value during arc discharge/glow discharge was periodically changed for each target. Thereby, the ionization amount of the target metal can be changed periodically, and the content ratio of each metal element can be changed periodically in the thickness direction of the first coating layer.

　Each sample No. 1 to No. The manufacturing conditions of the first coating layer for No. 16 are as shown in FIG. Sample no. 1 to No. 16, sample no. Sample Nos. other than 10; 1 to No. 9, No. 11 to No. 15 used an Al metal target as the first target, a Cr metal target as the second target, and an Al—Si composite alloy target as the third target. Samples N0.1 to No. 9, No. 11 to No. 15 is the period of the arc current, the magnitude of the arc current during the deposition of the first layer and the second layer for the first target, the arc current during the deposition of the first layer for the second target and the second The magnitude of the arc current during the deposition of the two layers and the combination of the magnitude of the arc current during the deposition of the first layer and the magnitude of the arc current during the deposition of the second layer with respect to the third target are different. Sample no. 10 used an Al metal target as the first target, a Cr metal target as the second target, and an Al—Si—Ti composite alloy target as the third target.

Fig. 8 shows sample No. 1 to No. 16 is a table summarizing the measurement results of the composition of the first coating layer and the metal content of No. 16. FIG.

As shown in FIG. 1 to No. 9, No. 11, No. 14 to No. The average composition of the first coating layer of sample No. 16 is (Al ₅₀ Cr ₃₉ Si ₁₁ )N. 10 has an average composition of the first coating layer of (Al ₅₀ Cr ₃₉ Si ₁₁ Ti ₃ )N. Moreover, sample no. The average composition of the first coating layer of sample No. 12 is (Al ₆₉ Cr ₁₁ Si ₂₀ )N. 13 has an average composition of the first coating layer of (Al ₇₀ Cr ₁₀ Si ₂₀ )N. Sample no. 1 to No. 16, sample no. For samples other than 10, the sum of Al, Cr, and Si in the metal elements contained in the first coating layer was 100 atomic %. Sample no. The total of Al, Cr, and Si in the metal elements contained in the ten first coating layers is 97 atomic %.

　Sample No. 1 to No. The layer thickness (average layer thickness) of the first layer and the second layer in 13 is about 5 nm. Moreover, sample no. The layer thickness (average layer thickness) of the first layer and the second layer in Sample No. 14 is about 10 nm. The layer thickness (average layer thickness) of the first layer and the second layer in Sample No. 15 is about 20 nm. The layer thickness (average layer thickness) of the first and second layers at 16 is about 30 nm.

These sample No. 1 to No. 16, the difference between the first Al content and the second Al content (the first Al content - the second Al content) is 6 atomic %, 2 atomic %, 4 atomic %, 6 atomic %, 8 atomic %, 9 atomic %, 10 atomic %, 9 atomic %, 6 atomic %, 6 atomic %, 6 atomic %, 8 atomic %, 6 atomic %, 6 atomic %, 6 atomic %, 6 atomic %.

Also, sample No. 1 to No. 16, the difference between the first Cr content and the second Cr content (the second Cr content - the first Cr content) is 8 atomic %, 3 atomic %, 6 atomic %, 9 atomic %, 12 atomic %, 11 atomic %, 11 atomic %, 13 atomic %, 12 atomic %, 8 atomic %, 4 atomic %, 4 atomic %, 8 atomic %, 8 atomic %, 8 atomic %, 8 atomic %.

Also, sample No. 1 to No. 16, the difference between the first Si content and the second Si content (samples No. 1 to No. 10, No. 13 to No. 16 are the first Si content - the second Si content, sample No. 11, No. .12 is the second Si content - the first Si content) is 2 atomic %, 1 atomic %, 2 atomic %, 3 atomic %, 4 atomic %, 2 atomic %, 1 atomic %, 4 atomic %, They were 6 atomic %, 2 atomic %, 2 atomic %, 4 atomic %, 2 atomic %, 2 atomic %, 2 atomic %, and 2 atomic %.

Fig. 9 shows sample No. 1 to No. 16 is a table summarizing the wear test results for No. 16; Each test condition of the abrasion test is as follows.

<Abrasion test>
The wear test was performed under the following conditions using a two-blade carbide ball end mill (model number: 2KMBL0200-0800-S4).
(1) Cutting method: Pocket machining (2) Work material: SKD11H
(3) Feed fz: 1320mm/min
(4) Cut: ap 0.08 mm x ae 0.20 mm
(5) Evaluation method: The wear width of the side flank after 20 m cutting was measured with a microscope.

The first Al content is larger than the second Al content, the first Cr content is smaller than the second Cr content, and the first Si content is larger than the second Si content. 13 to No. No. 16 exhibited excellent adhesion of the coating layer and high wear resistance. In particular, the ratio of Al in the metal elements of the first coating layer is 38 atomic % or more and 55 atomic % or less, the ratio of Cr is 33 atomic % or more and 48 atomic % or less, and the ratio of Si is 4 atoms. % or more and 15 atomic % or less, and the difference between the first Al content and the second Al content is 1 atomic % or more and 9 atomic % or less, and the difference between the first Cr content and the second Cr content is 1 atomic % or more and 12 atomic % or less, and the difference between the first Si content and the second Si content is 0.5 atomic % or more and 5 atomic % or less. 6 resulted in excellent wear resistance.

<EDX analysis>
Sample no. 1 was subjected to EDX analysis. Specifically, a range spanning a plurality of first and second layers is extracted from the EDX analysis data, and the extracted range is scanned in the direction along the stacking direction of the first and second layers (scanning direction). The changes in Al content, Cr content, Si content and N content in were measured. Analysis conditions are as follows.
(1) Sample pretreatment: Thinning by FIB method (μ-sampling method) (2) Elemental analysis (area analysis)
(3) Scanning transmission electron microscope: JEM-ARM200F manufactured by JEOL Ltd.
(4) Acceleration voltage: 200 kV
(5) Beam diameter: about 0.2 nmφ
(6) Elemental analyzer: JEOL JED-2300T
(7) X-ray detector: Si drift detector (8) Energy resolution: about 140 eV
(9) X-ray extraction angle: 21.9°
(10) Solid angle: 0.98sr
(11) Number of captured pixels: 256×256

FIG. 10 is a scanning transmission electron microscope image (HAADF-STEM image) of the first coating layer according to the embodiment. As shown in FIG. 10, the first coating layer according to the example has a striped structure in which the first layer and the second layer are alternately arranged.

FIG. 11 is a graph showing changes in Al content, Cr content, Si content and N content in the stacking direction of the first layer and the second layer. The horizontal axis of the graph shown in FIG. 11 corresponds to the scanning direction shown in FIG. That is, the starting point of the scanning direction shown in FIG. 10 ("0 nm" shown in FIG. 10) corresponds to "0 nm" on the horizontal axis of the graph shown in FIG. 50 nm”) corresponds to “50 nm” on the horizontal axis of the graph shown in FIG.

As shown in FIG. 11, it can be seen that the Al content and Cr content fluctuate periodically along the scanning direction (that is, the stacking direction of the first and second layers). Specifically, the Al content increases in the first layer and decreases in the second layer. Also, the Cr content decreases in the second layer and increases in the second layer.

In addition, the Si content also fluctuates periodically along the scanning direction. Specifically, the Si content increases in the first layer and decreases in the second layer, similar to the Al content.

Thus, in the first coating layer according to the example, the Al content (first Al content) in the first layer is greater than the Al content (second Al content) in the second layer, The 1 Cr content is less than the 2 Cr content in the second layer, and the first Si content in the first layer is greater than the second Si content in the second layer.

Also, as shown in FIG. 11, the difference between the first Al content and the second Al content is 1 atomic % or more and 9 atomic % or less.

Also, as shown in FIG. 11, the difference between the first Cr content and the second Cr content is found to be 1 atomic % or more and 12 atomic % or less.

Also, as shown in FIG. 11, the difference between the first Si content and the second Si content is 0.5 atomic % or more and 5 atomic % or less.

As described above, the coated tool according to the embodiment (coated tool 1 as an example) includes a base (base 10 as an example) and a coating layer (covering layer 20 as an example) located on the base. have. The coating layer has a first coating layer (as an example, the first coating layer 23) containing Al, Cr, Si and N. The first covering layer has a first layer (as an example, the first layer 23a) and a second layer (as an example, the second layer 23b) alternately positioned in the thickness direction. The first layer and the second layer contain Al, Cr, Si and N. The Al content in the first layer is the first Al content, the Cr content in the first layer is the first Cr content, the Si content in the first layer is the first Si content, and the Al content in the second layer is the second Al The Cr content in the second layer is defined as the second Cr content, and the Si content in the second layer is defined as the second Si content. In this case, the first Al content is greater than the second Al content, the first Cr content is less than the second Cr content, and the first Si content is greater than the second Si content.

Therefore, according to the coated tool according to the embodiment, oxidation resistance and wear resistance can be improved.

The shape of the coated tool 1 shown in FIG. 1 is merely an example, and does not limit the shape of the coated tool according to the present disclosure. A coated tool according to the present disclosure may, for example, include a rod-shaped body having an axis of rotation and extending from a first end to a second end, a cutting edge located at the first end of the body, and a cutting edge extending from the cutting edge to the second end of the body. It may have a groove extending spirally toward the side.

Further effects and modifications can be easily derived by those skilled in the art. Therefore, the broader aspects of the invention are not limited to the specific details and representative embodiments so shown and described. Accordingly, various changes may be made without departing from the spirit or scope of the general inventive concept defined by the appended claims and equivalents thereof.

REFERENCE SIGNS LIST 1 coated tool 2 tip body 5 through hole 10 substrate 20 coating layer 22 intermediate layer 23 first coating layer 23a first layer 23b second layer 24 second coating layer 70 holder 73 pocket 75 screw 100 cutting tool

Claims

having a substrate and a coating layer overlying the substrate;
The coating layer has a first coating layer containing Al, Cr, Si and N,
The first coating layer has a first layer and a second layer alternately positioned in the thickness direction,
the first layer and the second layer comprise Al, Cr, Si and N;
Let the Al content in the first layer be the first Al content, the Cr content in the first layer be the first Cr content, and the Si content in the first layer be the first Si content,
When the Al content in the second layer is the second Al content, the Cr content in the second layer is the second Cr content, and the Si content in the second layer is the second Si content,
The first Al content is greater than the second Al content,
The first Cr content is less than the second Cr content,
A coated tool, wherein the first Si content is greater than the second Si content.
The coated tool according to claim 1, wherein the total of Al, Cr and Si in the metal elements contained in the first coating layer is 98 atomic % or more.
The ratio of Al to the metal elements of the first coating layer is 38 atomic % or more and 55 atomic % or less,
The ratio of Cr to the metal elements of the first coating layer is 33 atomic % or more and 48 atomic % or less,
The coated tool according to claim 1 or 2, wherein the proportion of Si in the metal elements of said first coating layer is 4 atomic% or more and 15 atomic% or less.
The coated tool according to any one of claims 1 to 3, wherein the difference between the first Al content and the second Al content is 1 atomic % or more and 9 atomic % or less.
The coated tool according to any one of claims 1 to 4, wherein the difference between the first Cr content and the second Cr content is 1 atomic % or more and 12 atomic % or less.
The coated tool according to any one of claims 1 to 5, wherein the difference between the first Si content and the second Si content is 0.5 atomic % or more and 5 atomic % or less.
The coated tool according to any one of claims 1 to 6, wherein the thicknesses of the first layer and the second layer are 1 nm or more and 20 nm or less.
a rod-shaped holder having a pocket at its end;
and a coated tool according to any one of claims 1 to 7, located within said pocket.