Cutting tools

Abstract

A cutting tool comprising a substrate and a coating disposed on the substrate, wherein the coating comprises a first layer and a second layer, the first layer having a hardness H1 of 25 GPa or more and 40 GPa or less, and the second layer having a hardness H2 satisfying 0.5 × H1 ≤ H2 ≤ 0.9 × H1, and an X-ray diffraction intensity I relative to the (200) plane of the coating. (200) X-ray diffraction intensity I of plane (111) (111) X-ray diffraction intensity I of plane (220) (220) The total of the I (200) The ratio I (200) / (I (200) +I (111) +I (220) ), relative to the total of I (111) The ratio I (111) / (I (200) +I (111) +I (220) ), and the I relative to the total (220) The ratio I (220) / (I (200) +I (111) +I (220) At least one of the values ​​in the equation is 0.45 or higher.

Description

Technical Field

[0001] This disclosure relates to cutting tools. This application claims priority based on international application PCT / JP2021 / 024828, filed June 30, 2021. The entire contents of that international application are incorporated herein by reference. Background Technology

[0002] Various studies have been conducted with the aim of extending the lifespan of cutting tools. Japanese Patent Application Publication No. 2018-69433 (Patent Document 1) discloses a cutting tool having a coating comprising Ti... x M 1-x C y N 1-y (M is a compound layer composed of one or more elements selected from the group consisting of Group 4, Group 5, Group 6, Al, Si and B (excluding Ti), satisfying 0.2≤x≤1 and 0≤y≤1) and having an elastic recovery rate of 52% or higher.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-69433 Summary of the Invention

[0006] The cutting tool disclosed herein includes a substrate and a coating disposed on the substrate, wherein,

[0007] The coating consists of a first layer and a second layer.

[0008] The hardness H1 of the first layer is above 25 GPa and below 40 GPa.

[0009] The hardness H2 of the second layer satisfies 0.5×H1≤H2≤0.9×H1.

[0010] X-ray diffraction intensity I relative to the (200) plane of the coating (200) X-ray diffraction intensity I of plane (111) (111) X-ray diffraction intensity I of plane (220) (220) The total of the I (200) The ratio I (200) / (I (200) +I (111) +I (220) ),

[0011] Relative to the total of I (111) The ratio I (111) / (I(200) +I (111) +I (220) ),as well as

[0012] Relative to the total of I (220) The ratio I (220) / (I (200) +I (111) +I (220) At least one of the values ​​in the equation is 0.45 or higher. Attached Figure Description

[0013] Figure 1 This is a perspective view illustrating one way of using a cutting tool.

[0014] Figure 2 This is a schematic cross-sectional view of the cutting tool in one embodiment of this invention.

[0015] Figure 3 This is a schematic cross-sectional view of the cutting tool in another embodiment of this invention.

[0016] Figure 4 This is a schematic cross-sectional view of the cutting tool in another embodiment of this invention.

[0017] Figure 5 This is a schematic cross-sectional view of the cutting tool in another embodiment of this invention.

[0018] Figure 6 This is a schematic cross-sectional view of the cutting tool in this embodiment, which includes a base layer in the coating.

[0019] Figure 7 This is a schematic cross-sectional view of the cutting tool in this embodiment, which includes an intermediate layer in the coating.

[0020] Figure 8 This is a schematic cross-sectional view of the cutting tool in this embodiment, which includes a surface layer in the coating.

[0021] Figure 9 This is a schematic diagram of a graph representing an example of the results obtained by performing X-ray diffraction measurements on a coating. Detailed Implementation

[0022] [The problem this disclosure aims to solve]

[0023] In recent years, cutting tools have tended to be exposed to harsh cutting conditions due to the demands of high-load cutting. Currently, however, there are no cutting tools that can be reliably used under harsh cutting conditions; in other words, there are no cutting tools with a sufficiently long tool life. This is especially true in high-load cutting (particularly interrupted machining) of high-hardness materials such as hardened steel, where resistance to peeling and chipping is sometimes insufficient. Therefore, there is a demand for cutting tools that maintain a long tool life even in high-load cutting (particularly interrupted machining) of high-hardness materials such as hardened steel.

[0024] Therefore, the purpose of this disclosure is to provide a cutting tool that has a long tool life even in high-load cutting of high-hardness materials.

[0025] [The Effects of This Disclosure]

[0026] According to this disclosure, it is possible to provide a cutting tool that has a long tool life even in high-load cutting of high-hardness materials.

[0027] [Description of embodiments of this disclosure]

[0028] First, embodiments of this disclosure will be described.

[0029] (1) A cutting tool comprising a substrate and a coating disposed on the substrate, wherein...

[0030] The coating consists of a first layer and a second layer.

[0031] The hardness H1 of the first layer is above 25 GPa and below 40 GPa.

[0032] The hardness H2 of the second layer satisfies 0.5×H1≤H2≤0.9×H1.

[0033] X-ray diffraction intensity I relative to the (200) plane of the coating (200) X-ray diffraction intensity I of plane (111) (111) X-ray diffraction intensity I of plane (220) (220) The total of the I (200) The ratio I (200) / (I (200) +I (111) +I (220) ),

[0034] Relative to the total of I (111) The ratio I (111) / (I (200) +I (111) +I (220) ),as well as

[0035] Relative to the total of I (220) The ratio I (220) / (I (200) +I (111) +I (220) At least one of the values ​​in the equation is 0.45 or higher.

[0036] The cutting tool disclosed herein can have a long tool life even in high-load cutting of high-hardness materials.

[0037] (2) Preferably, in (1) above, the thickness of the first layer is 0.2 μm or more and 10 μm or less. As a result, the wear resistance of the cutting tool is further improved.

[0038] (3) Preferably, in (1) or (2) above, the thickness of the second layer is 0.2 μm or more and 10 μm or less. This further improves the chipping resistance and peeling resistance of the cutting tool.

[0039] (4) Preferably, in any one of (1) to (3) above, the ratio T1 / T2 of the thickness T1 of the first layer to the thickness T2 of the second layer is 0.02 or more and 50 or less. As a result, the balance of wear resistance, peel resistance and chipping resistance of the cutting tool is further improved.

[0040] (5) Preferably, in any one of (1) to (4) above, the first layer comprises a first unit layer.

[0041] The first unit layer is composed of Ti x Al y M 1-x-y C z N 1-z constitute,

[0042] The element M is selected from the group consisting of zirconium, hafnium, elements from Group 5 of the periodic table, elements from Group 6 of the periodic table, silicon, boron, and yttrium.

[0043] The x-value is greater than 0.20 and less than 0.99.

[0044] The value of y is above 0.01 and below 0.80.

[0045] The 1-xy is greater than 0.01 and less than 0.20.

[0046] The z-value is greater than 0 and less than 1. Therefore, the wear resistance of the cutting tool is further improved.

[0047] (6) Preferably, in (5) above, the first layer further includes a second unit layer.

[0048] The second unit layer is composed of Alm Cr 1-m N constitutes,

[0049] The value of m is greater than 0 and less than 0.8.

[0050] The thickness of the first unit layer is greater than 5 nm and less than 50 nm.

[0051] The thickness of the second unit layer is greater than 5 nm and less than 50 nm.

[0052] The first unit layer and the second unit layer are stacked alternately. As a result, the wear resistance of the cutting tool is further improved.

[0053] (7) Preferably, in (5) above, the first layer further includes a third unit layer.

[0054] This third unit layer is composed of Ti 1-n Al n N constitutes,

[0055] The value of n is greater than 0 and less than 0.8.

[0056] The thickness of the first unit layer is greater than 5 nm and less than 50 nm.

[0057] The thickness of the third unit layer is greater than 5 nm and less than 50 nm.

[0058] The first unit layer and the third unit layer are stacked alternately. As a result, the wear resistance of the cutting tool is further improved.

[0059] (8) Preferably, in any one of (1) to (7) above, the second layer includes a fourth unit layer.

[0060] The fourth unit layer is composed of Ti a Al b C c N 1-c constitute,

[0061] The value of 'a' is greater than 0.2 and less than 1.0.

[0062] The value of b is greater than 0 and less than 0.8.

[0063] The value of c is greater than 0 and less than 1. Therefore, the chipping resistance and peeling resistance of the cutting tool are further improved.

[0064] [Details of the embodiments disclosed herein]

[0065] Hereinafter, a specific example of a cutting tool according to one embodiment of the present disclosure (hereinafter also referred to as "this embodiment") will be described with reference to the accompanying drawings. In the drawings of this disclosure, the same reference numerals denote the same or equivalent parts. In addition, dimensional relationships such as length, width, thickness, and depth have been appropriately modified for the clarity and simplification of the drawings, and do not necessarily represent actual dimensional relationships.

[0066] In this specification, expressions such as "A~B" refer to the upper and lower limits of a range (i.e., above A and below B). If no unit is recorded in A but only in B, the unit of A is the same as the unit of B.

[0067] In this specification, when compounds are represented by chemical formulas, all conventionally known atomic ratios are included unless otherwise specified, and are not necessarily limited to atomic ratios within the stoichiometric range. For example, when referred to as "TiAlSiN", the ratio of the number of atoms constituting TiAlSiN includes all conventionally known atomic ratios.

[0068] In the crystallographic descriptions in this specification, a single surface is indicated by ().

[0069] [Implementation Method 1: Cutting Tool]

[0070] like Figure 2 as well as Figure 3 As shown, the cutting tool 10 according to this embodiment includes a substrate 11 and a coating 40 disposed on the substrate 11, wherein,

[0071] The coating 40 comprises a first layer 12 and a second layer 13.

[0072] The hardness H1 of the first layer 12 is above 25 GPa and below 40 GPa.

[0073] The hardness H2 of the second layer 13 satisfies 0.5×H1≤H2≤0.9×H1.

[0074] X-ray diffraction intensity I relative to the (200) plane of the coating (200) X-ray diffraction intensity I of plane (111) (111) X-ray diffraction intensity I of plane (220) (220) The total of the I (200) The ratio I (200) / (I (200) +I (111) +I (220) ),

[0075] Relative to the total of I (111) The ratio I (111) / (I (200) +I(111) +I (220) ),as well as

[0076] Relative to the total of I (220) The ratio I (220) / (I (200) +I (111) +I (220) At least one of the values ​​in the equation is 0.45 or higher.

[0077] The cutting tool disclosed herein can maintain a long tool life even in high-load cutting (especially high-load cutting such as interrupted machining) of high-hardness materials such as hardened steel. The reason for this is speculated as follows.

[0078] (a) The aforementioned coating comprises a first layer, wherein the hardness H1 of the first layer 12 is 25 GPa or more and 40 GPa or less. Therefore, such a cutting tool can possess excellent wear resistance. It should be noted that, here, "wear resistance" refers to resistance to wear of the coating during cutting operations.

[0079] (b) As shown in (a) above, the coating comprises a first layer, wherein the hardness H1 of the first layer 12 is 25 GPa or more and 40 GPa or less. Coatings with such hardness exhibit excellent wear resistance. However, such coatings are generally brittle, and therefore tend to be prone to damage (coating cracking and peeling) due to the coating itself being destroyed. Therefore, in cutting tools with such coatings, during high-load cutting (especially interrupted machining) of high-hardness materials such as hardened steel, there is a tendency for the coating itself to be destroyed, leading to damage and accelerated wear starting from this damage.

[0080] However, in the cutting tool of this embodiment, the coating has a second layer in addition to the first layer described above. The hardness H2 of the second layer 13 satisfies 0.5×H1≤H2≤0.9×H1, thereby suppressing the overall brittleness of the coating and thus suppressing damage caused by the destruction of the coating itself (minor defects in the coating and peeling of the coating). Therefore, the cutting tool of this embodiment exhibits excellent peel resistance and excellent chipping resistance even in high-load cutting (especially high-load cutting such as interrupted machining) of high-hardness materials such as hardened steel, and can suppress the aggravation of wear starting from coating damage. It should be noted that, here, "peel resistance" refers to the resistance to the coating peeling off from the substrate. In addition, here, "chipping resistance" refers to the resistance to the formation of minor defects in the coating.

[0081] (c) Furthermore, in the cutting tool of this embodiment, the X-ray diffraction intensity I relative to the (200) plane of the aforementioned coating (200) X-ray diffraction intensity I of plane (111) (111) X-ray diffraction intensity I of plane (220) (220) The total of the above I (200) The ratio I (200) / (I (200) +I (111) +I (220) ), relative to the above total of the above I (111) The ratio I (111) / (I (200) +I (111) +I (220) ), and the above I relative to the total above. (220) The ratio I (220) / (I (200) +I (111) +I (220) At least one of the following is 0.45 or higher. Therefore, the orientation deviation between the first layer and the second layer, which is configured to be closest to the first layer, can be suppressed to a low level, resulting in consistent orientation and thus improved adhesion between the first and second layers. Therefore, the peel resistance of such a cutting tool can be improved.

[0082] That is, the cutting tool involved in this embodiment has a long tool life by combining excellent wear resistance, excellent peel resistance and excellent chipping resistance.

[0083] The shape and application of the cutting tool 10 involved in this embodiment are not particularly limited. For example, the cutting tool 10 involved in this embodiment can be a drill bit, an end mill, an indexable cutting insert for a drill bit, an indexable cutting insert for an end mill, an indexable cutting insert for milling, an indexable cutting insert for turning, a metal saw, a gear cutting tool, a reamer, a tap, a cutting insert for crankshaft pin grinding, etc.

[0084] Figure 1 This is a perspective view illustrating one embodiment of the cutting tool 10 of this disclosure. The cutting tool 10 of this shape is used as an indexable cutting insert, such as a turning insert.

[0085] Substrate

[0086] The substrate used in this embodiment can be any substrate that is conventionally known as such a substrate, and any substrate can be used. For example, the substrate preferably includes one selected from the group consisting of cemented carbide (e.g., tungsten carbide (WC) based cemented carbide, cemented carbide containing Co in addition to WC, cemented carbide containing carbonitrides such as Ti, Ta, and Nb in addition to WC), cermet (cermet with TiC, TiN, TiCN, etc. as the main components), high-speed steel, tool steel, ceramics (TiC, SiC, SiN, AlN, Al2O3, silane and mixtures thereof, etc.), cubic boron nitride sintered body (cBN sintered body), diamond sintered body, and hard materials in which cubic boron nitride particles are dispersed in the bonding phase.

[0087] Among these various substrates, cemented carbide (especially WC-based cemented carbide) and cermet (especially TiCN-based cermet) are particularly preferred. This is because these substrates exhibit excellent balance between hardness and strength, especially at high temperatures, making them superior materials for cutting tools used in the aforementioned applications.

[0088] When using cemented carbide as the substrate, the effects of this embodiment are observed even when the microstructure contains abnormal phases known as free carbon or η phase. It should be noted that the substrate used in this embodiment can also be a substrate whose surface has been modified. For example, in the case of cemented carbide, a de-β layer can be formed on its surface, or in the case of cBN sintered body, a surface-hardened layer can be formed; even with such surface modification, the effects of this embodiment are observed.

[0089] When the cutting tool is an indexable cutting insert (indexable cutting insert for turning, indexable cutting insert for milling, etc.), the base material includes both base materials with and without chip breakers. The shape of the tool tip includes any shape among sharp edges (the edge where the rake face and flank face intersect), honing (a shape with rounded corners on the sharp edges), negative cutting edge (a chamfered shape), and a combination of honing and negative cutting edge.

[0090] Covering

[0091] The coating 40 is disposed on the substrate 11. Figure 2 , Figure 3 ). Figure 2 This is a schematic cross-sectional view illustrating one manner of the cutting tool of this disclosure. Figure 3This is a schematic cross-sectional view illustrating another embodiment of the cutting tool of this disclosure. The "coating" improves the cutting tool's resistance to peeling, chipping, and wear by covering at least the tip portion of the substrate 11. The tip portion, as described herein, refers to the area within 500 μm along the surface of the substrate from the tip edge. Preferably, the coating 40 covers the entire surface of the substrate 11. However, even if a portion of the substrate 11 is not covered by the coating 40, or if the composition of the coating 40 is partially different, it does not depart from the scope of this embodiment.

[0092] The thickness of the aforementioned coating is preferably 0.1 μm or more and 30 μm or less, more preferably 0.4 μm or more and 20 μm or less, even more preferably 0.5 μm or more and 10 μm or less, even more preferably 0.7 μm or more and 5 μm or less, and particularly preferably 1 μm or more and 3 μm or less. Here, the thickness of the coating refers to the sum of the thicknesses of the individual layers constituting the coating. Examples of "layers constituting the coating" include, for example, the first layer described above, the second layer described above, and other layers described later that are not the first layer or the second layer described above.

[0093] The thickness of the aforementioned coating can be determined, for example, by using a scanning electron microscope (SEM) to measure the thickness at any five points in a cross-sectional sample parallel to the normal direction of the substrate surface, and then taking the average of the thicknesses at the five points. The cross-sectional sample can be prepared, for example, using a focused ion beam apparatus or a cross-sectional polishing machine. The same procedure applies to measuring the thicknesses of the first layer, the second layer, the first unit layer, the second unit layer, the third unit layer, the fourth unit layer, and the other layers.

[0094] The aforementioned coating comprises a first layer and a second layer. Furthermore, in one aspect of this embodiment, multiple first layers may be provided as long as the effect of the cutting tool is maintained. Similarly, multiple second layers may be provided as long as the effect of the cutting tool is maintained. Therefore, even if a portion of the coating is worn, the cutting tool can maintain the coating's wear resistance, crack resistance, and peel resistance because the first and second layers remain in the coating. Furthermore, either the first or second layer may be located on the surface closest to the coating. Also, either the first or second layer may be located on the substrate closest to the coating. Additionally, "comprising a first layer and a second layer" means that the coating may include other layers described later as layers other than the first and second layers.

[0095] X-ray diffraction intensity I relative to the (200) plane of the above-mentioned coating (200) X-ray diffraction intensity I of plane (111)(111) X-ray diffraction intensity I of the (220) plane (220) The total of the above I (200) The ratio I (200) / (I (200) +I (111) +I (220) ), relative to the above total of the above I (111) The ratio I (111) / (I (200) +I (111) +I (220) ), and the above I relative to the total above. (220) The ratio I (220) / (I (200) +I (111) +I (220) At least one of the values ​​in () is 0.45 or higher. Therefore, the orientation deviation between the first layer and the second layer, which is configured to be closest to the first layer, can be suppressed to a low level, making the orientation consistent, and thus improving the adhesion between the first and second layers. Therefore, the peel resistance of such a cutting tool can be improved. It should be noted that, here, "X-ray diffraction intensity I of the (200) plane" (200) "" refers to the diffraction intensity (peak height) at the highest peak among the X-ray diffraction peaks from the (200) plane (hereinafter also referred to as "maximum diffraction intensity"). Additionally, as... Figure 9 As shown, when two or more compounds contained in the coating have X-ray diffraction peaks A1 and A2 from the (200) plane respectively, that is, when the X-ray diffraction peaks from the (200) plane are located at different positions, "the X-ray diffraction intensity I of the (200) plane" (200) "" refers to the sum of their maximum diffraction intensities (peak heights). For the X-ray diffraction intensity I of the "(111) plane (111) "and "X-ray diffraction intensity I of plane (220) (220) The same applies to "".

[0096] In addition, the above I (200) / (I (200) +I (111) +I (220) ), the above I (111) / (I (200) +I (111) +I (220) ), and the aforementioned I (220) / (I (200) +I (111) +I (220) At least one of the following is preferably 0.47 or higher, more preferably 0.50 or higher, and even more preferably 0.55 or higher. Additionally, the above-mentioned I...(200) / (I (200) +I (111) +I (220) ), the above I (111) / (I (200) +I (111) +I (220) ), and the aforementioned I (220) / (I (200) +I (111) +I (220) At least one of the following is preferably 0.90 or less, more preferably 0.85 or less, and even more preferably 0.80 or less. Additionally, the above-mentioned I... (200) / (I (200) +I (111) +I (220) ), the above I (111) / (I (200) +I (111) +I (220) ), and the aforementioned I (220) / (I (200) +I (111) +I (220) At least one of the following is preferably 0.47 or higher and 0.90 or lower, more preferably 0.50 or higher and 0.85 or lower, and even more preferably 0.55 or higher and 0.80 or lower.

[0097] The above I (200) The above I (111) and the aforementioned I (220) For example, it can be determined by X-ray diffraction (XRD) measurements performed under the following conditions. Specifically, the surface of the above-mentioned coating is irradiated with X-rays, and X-ray diffraction (XRD) measurements are performed to determine the X-ray diffraction intensities of the (200) plane, (111) plane, and (220) plane, and the above-mentioned I is calculated. (200) The above I (111) and the aforementioned I (220) In addition, examples of devices used in the aforementioned X-ray diffraction measurements include "SmartLab" (trade name) manufactured by Rigaku Co., Ltd., and "X'pert" (trade name) manufactured by PANalytical.

[0098] (Conditions for X-ray diffraction measurement)

[0099] Scan axis: 2θ-θ

[0100] X-ray source: Cu-Kα rays

[0101] Detector: 0-dimensional detector (scintillation counter)

[0102] Tube voltage: 45kV

[0103] Tube current: 40mA

[0104] Incident optical system: using a mirror

[0105] Light-receiving optical system: utilizing an analyzer crystal (PW3098 / 27)

[0106] Step size: 0.03°

[0107] Total time: 2 seconds

[0108] Scan range (2θ): 10°~120°

[0109] It has been confirmed that, in the cutting tool of this embodiment, as long as the measurement is performed on the same cutting tool, the same result can be obtained even if different measurement ranges are arbitrarily selected and the above measurement is performed within those measurement ranges.

[0110] <First Layer>

[0111] (Hardness of the first layer)

[0112] In this embodiment, the hardness H1 of the first layer is 25 GPa or more and 40 GPa or less. Therefore, the cutting tool can exhibit excellent wear resistance. Furthermore, H1 is preferably 27 GPa or more, more preferably 29 GPa or more, and even more preferably 31 GPa or more. Additionally, H1 is preferably 38 GPa or less, more preferably 36 GPa or less, and even more preferably 34 GPa or less. Furthermore, H1 is preferably 27 GPa or more and 38 GPa or less, more preferably 29 GPa or more and 36 GPa or less, and even more preferably 31 GPa or more and 34 GPa or less.

[0113] The hardness H1 of the first layer was determined according to ISO 14577 (2015), measuring the indentation hardness. The measuring equipment used was a nanoindentation hardness tester (ENT1100a; manufactured by Elionix). Specifically, firstly, the cutting tool was ground to obtain a surface (inclined surface) with a 6° inclination relative to the outermost surface of the coating. Next, at any point on the surface of the first layer in the obtained inclined surface, corresponding to the midpoint of the first layer's film thickness direction, an indentation load controlled to be less than 1 / 10 of the first layer's film thickness was applied at an environment of 25°C to 30°C, and a measurement based on the nanoindentation method was performed. By performing the above measurement, the hardness H1 of the first layer was calculated according to ISO 14577. The same procedure was followed when measuring the hardness H2 of the second layer. It should be noted that when the first layer comprises a first unit layer, a second unit layer, or a third unit layer, the hardness H1 of the first layer refers to the overall hardness of the first layer.

[0114] It has been confirmed that, even if different measurement ranges are arbitrarily selected and the above measurements are performed within those ranges, the same results can be obtained with the same cutting tool.

[0115] (Thickness of the first layer)

[0116] The thickness of the first layer is preferably 0.2 μm or more and 10 μm or less. This further improves the wear resistance of the cutting tool. Furthermore, the thickness of the first layer is preferably 0.4 μm or more, more preferably 0.5 μm or more, and even more preferably 0.6 μm or more. Additionally, the thickness of the first layer is preferably 6 μm or less, more preferably 3 μm or less, and even more preferably 2 μm or less. Furthermore, the thickness of the first layer is preferably 0.4 μm or more and 6 μm or less, more preferably 0.5 μm or more and 3 μm or less, and even more preferably 0.6 μm or more and 2 μm or less.

[0117] (First Unit Layer)

[0118] Preferably, the first layer comprises a first unit layer, wherein the first unit layer is composed of Ti x Al y M 1-x-y C z N 1-zThe composition is as follows: M is an element selected from the group consisting of zirconium, hafnium, elements of Group 5 of the periodic table, elements of Group 6 of the periodic table, silicon, boron, and yttrium; x is 0.20 or more and 0.99 or less; y is 0.01 or more and 0.80 or less; 1-xy is 0.01 or more and 0.20 or less; and z is 0 or more and 1.0 or less. This further improves the wear resistance of cutting tools. Here, "the first layer includes the first unit layer" refers to a first layer consisting solely of the first unit layer, or a first layer including both the first unit layer and a second or third unit layer (described later). Furthermore, "the first unit layer is composed of Ti..." x Al y M 1-x-y C z N 1-z "Construction" is a concept that includes, but is not limited to, only Ti. x Al y M 1-x-y C z N 1-z The configuration method, as long as it achieves the effect of this disclosure, also includes the inclusion of Ti. x Al y M 1-x-y C z N 1-z It also includes Ti x Al y M 1-x-y C z N 1-z Other components (e.g., unavoidable impurities) in a way that...

[0119] Furthermore, x is preferably 0.25 or more and 0.95 or less, more preferably 0.30 or more and 0.90 or less, and even more preferably 0.35 or more and 0.80 or less.

[0120] Furthermore, the value of y is preferably 0.10 or higher and 0.70 or lower, more preferably 0.20 or higher and 0.60 or lower, and even more preferably 0.30 or higher and 0.55 or lower.

[0121] Furthermore, the aforementioned 1-xy is preferably 0.02 or more and 0.18 or less, more preferably 0.03 or more and 0.15 or less, and even more preferably 0.04 or more and 0.10 or less.

[0122] Furthermore, z is preferably 0.01 or more and 0.90 or less, more preferably 0.05 or more and 0.70 or less, and even more preferably 0.10 or more and 0.50 or less.

[0123] When the first layer consists only of the first unit layer, x can be 0.20 or higher and 0.99 or lower, y can be 0.01 or higher and 0.80 or lower, 1-xy can be 0 and z can be 0 or higher and 1.0 or lower. Furthermore, when the first layer includes the first unit layer and also includes the second unit layer and / or the third unit layer (described later), it is preferable that 1-xy is not "0".

[0124] The aforementioned x, y, and z can be confirmed using an EDX (Energy Dispersive X-ray spectroscopy) device equipped with SEM or TEM. Specifically, firstly, a sample containing the coating is prepared by cutting at an arbitrary point along the film thickness direction using a cutting tool. Next, point analysis is performed on the first unit layer in the coating. It should be noted that the measurement site is set at the midpoint of the thickness direction of the first unit layer, excluding information near the interface. This measurement is performed at five arbitrarily selected sites. At each of the five measurement sites, x and y representing the atomic ratio of each element are determined. The average value of x and y at each of the five measurement sites is calculated. This average value corresponds to the aforementioned x and y in the first unit layer. It should be noted that the same procedure applies when calculating m for the second unit layer (described later), n for the third unit layer (described later), and a, b, and c for the fourth unit layer (described later).

[0125] When the first layer is composed solely of the first unit layer, the thickness of the first unit layer is preferably 0.2 μm or more and 10 μm or less. This further improves the wear resistance of the cutting tool. Furthermore, when the first layer is composed solely of the first unit layer, the thickness of the first unit layer is preferably 0.4 μm or more, more preferably 0.5 μm or more, and even more preferably 0.6 μm or more. Furthermore, when the first layer is composed solely of the first unit layer, the thickness of the first unit layer is preferably 6 μm or less, more preferably 3 μm or less, and even more preferably 2 μm or less. Furthermore, when the first layer is composed solely of the first unit layer, the thickness of the first unit layer is preferably 0.4 μm or more and 6 μm or less, more preferably 0.5 μm or more and 3 μm or less, and even more preferably 0.6 μm or more and 2 μm or less.

[0126] When the first layer comprises the first unit layer, the second unit layer, or the third unit layer, the thickness of the first unit layer is preferably 0.005 μm or more and 1 μm or less. This further improves the wear resistance of the cutting tool. Furthermore, when the first layer comprises the first unit layer, the second unit layer, or the third unit layer, the thickness of the first unit layer is preferably 0.007 μm or more, more preferably 0.010 μm or more, and even more preferably 0.015 μm or more. Additionally, when the first layer comprises the first unit layer, the second unit layer, or the third unit layer, the thickness of the first unit layer is preferably 0.8 μm or less, more preferably 0.6 μm or less, and even more preferably 0.3 μm or less. Furthermore, when the first layer includes the first unit layer, the second unit layer, or the third unit layer, the thickness of the first unit layer is preferably 0.005 μm or more and 0.8 μm or less, more preferably 0.010 μm or more and 0.6 μm or less, and even more preferably 0.015 μm or more and 0.3 μm or less.

[0127] (Second Unit Layer)

[0128] Preferably, the first layer 12 includes a second unit layer 13 in addition to the first unit layer. Furthermore, in this case, preferably, the second unit layer 13 is composed of A1. m Cr 1-m N is formed, m is 0 or more and 0.8 or less, the thickness of the first unit layer 121 is 5 nm or more and 50 nm or less, the thickness of the second unit layer 122 is 5 nm or more and 50 nm or less, and the first unit layer 121 and the second unit layer 122 are alternately stacked. Figure 4 Therefore, because the particle size of the particles constituting the first layer becomes finer, the hardness of the first layer increases, thus further improving the wear resistance of the cutting tool. Here, as long as the "first unit layer and the second unit layer are alternately stacked," either the first unit layer or the second unit layer can be disposed on the side closest to the substrate, or either the first unit layer or the second unit layer can be disposed on the side closest to the surface. Furthermore, here, "the second unit layer is made of Al..." m Cr 1-m "N composition" is a concept that is not limited to only Al. m Cr 1-m The configuration of N, as long as it achieves the effect of this disclosure, also includes configurations containing Al. m Cr 1-m N also contains Al m Cr 1-m The way of components other than N (e.g., unavoidable impurities).

[0129] Furthermore, the value of m is preferably 0.10 or more and 0.75 or less, more preferably 0.20 or more and 0.73 or less, and even more preferably 0.30 or more and 0.70 or less.

[0130] The thickness of the second unit layer is preferably 5 nm or more and 1 μm or less. This further improves the wear resistance of the cutting tool. Furthermore, the thickness of the second unit layer is preferably 7 nm or more, more preferably 10 nm or more, and even more preferably 15 nm or more. Additionally, the thickness of the second unit layer is preferably 0.8 μm or less, more preferably 0.6 μm or less, and even more preferably 0.3 μm or less. Furthermore, the thickness of the second unit layer is preferably 5 nm or more and 0.8 μm or less, more preferably 10 nm or more and 0.6 μm or less, and even more preferably 15 nm or more and 0.3 μm or less.

[0131] (Third Unit Layer)

[0132] Preferably, the first layer 12 includes a third unit layer 123 in addition to the first unit layer. Furthermore, in this case, preferably, the third unit layer 123 is made of Ti. 1-n Al n N is formed, where n is 0 or more and 0.8 or less; the thickness of the first unit layer 121 is 5 nm or more and 50 nm or less; the thickness of the third unit layer 123 is 5 nm or more and 50 nm or less; and the first unit layer 121 and the third unit layer 123 are alternately stacked. Figure 5 Therefore, because the particle size of the first layer constituting the cutting tool becomes finer, the hardness of the first layer increases, thus further improving the wear resistance of the cutting tool. As long as the "first unit layer and the third unit layer are alternately stacked," either the first unit layer or the third unit layer can be disposed on the side closest to the substrate, or either the first unit layer or the third unit layer can be disposed on the side closest to the surface. Furthermore, here, "the third unit layer is made of Ti..." 1-n Al n "N composition" is a concept that is not limited to only Ti. 1-n Al n The configuration of N, as long as it achieves the effect of this disclosure, also includes the configuration containing Ti. 1-n Al n N also contains Ti 1-n Al n The way of components other than N (e.g., unavoidable impurities).

[0133] Furthermore, the aforementioned n is preferably 0.3 or more and 0.9 or less, more preferably 0.4 or more and 0.8 or less, and even more preferably 0.5 or more and 0.7 or less.

[0134] The thickness of the third unit layer is preferably 5 nm or more and 1 μm or less. This further improves the wear resistance of the cutting tool. Furthermore, the thickness of the third unit layer is preferably 7 nm or more, more preferably 10 nm or more, and even more preferably 15 nm or more. Additionally, the thickness of the third unit layer is preferably 0.8 μm or less, more preferably 0.6 μm or less, and even more preferably 0.3 μm or less. Furthermore, the thickness of the third unit layer is preferably 5 nm or more and 0.8 μm or less, more preferably 10 nm or more and 0.6 μm or less, and even more preferably 15 nm or more and 0.3 μm or less.

[0135] <Second Layer>

[0136] (Hardness of the second layer)

[0137] The hardness H2 of the second layer involved in this embodiment satisfies: 0.5 × H1 ≤ H2 ≤ 0.9 × H1. Therefore, the cutting tool can possess excellent peel resistance and excellent chipping resistance. Preferably, H2 satisfies H2 ≥ 0.53 × H1, more preferably H2 ≥ 0.56 × H1, and even more preferably H2 ≥ 0.6 × H1. Furthermore, preferably, H2 ≤ 0.87 × H1, more preferably H2 ≤ 0.84 × H1, and even more preferably H2 ≤ 0.8 × H1. Additionally, preferably, H2 satisfies 0.53 × H1 ≤ H2 ≤ 0.87 × H1, more preferably 0.56 × H1 ≤ H2 ≤ 0.84 × H1, and even more preferably 0.6 × H1 ≤ H2 ≤ 0.8 × H1.

[0138] (Thickness of the second layer)

[0139] The thickness of the second layer is preferably 0.2 μm or more and 10 μm or less. This further improves the chipping resistance and peeling resistance of the cutting tool. Furthermore, the thickness of the second layer is preferably 0.3 μm or more, more preferably 0.4 μm or more, and even more preferably 0.5 μm or more. Additionally, the thickness of the second layer is preferably 8 μm or less, more preferably 5 μm or less, and even more preferably 3 μm or less. Furthermore, the thickness of the second layer is preferably 0.3 μm or more and 8 μm or less, more preferably 0.4 μm or more and 5 μm or less, and even more preferably 0.5 μm or more and 3 μm or less.

[0140] The ratio T1 / T2 of the thickness T1 of the first layer to the thickness T2 of the second layer is preferably 0.02 or more and 50 or less. This improves the balance of wear resistance, peel resistance, and chipping resistance, thereby further increasing the life of the cutting tool. Furthermore, T1 / T2 is preferably 0.04 or more, more preferably 0.06 or more, and even more preferably 0.1 or more. Additionally, T1 / T2 is preferably 45 or less, more preferably 40 or less, and even more preferably 30 or less.

[0141] (Fourth Unit Layer)

[0142] Preferably, the second layer includes the fourth unit layer. Furthermore, in this case, preferably, the fourth unit layer is composed of Ti. a Al b C c N 1-c The composition is such that a is 0.2 or more and 1.0 or less, b is 0 or more and 0.8 or less, and c is 0 or more and 1.0 or less. Therefore, without compromising the adhesion between the first and second layers, the generation of cracks in the second layer can be effectively suppressed, thus further improving the chipping resistance of the cutting tool. Furthermore, this method suppresses both chipping and cracking that become the starting point of peeling in the second layer, further improving the peeling resistance of the cutting tool. Here, "the second layer includes a fourth unit layer" includes both a second layer composed solely of a fourth unit layer and a second layer containing layers other than the fourth unit layer while also including the fourth unit layer. Here, "the fourth unit layer is composed of Ti..." a Al b C c N 1-c "Construction" is a concept that includes, but is not limited to, only Ti. a Al b C c N 1-c The configuration method, as long as it achieves the effect of this disclosure, also includes the inclusion of Ti. a Al b C c N 1-c It also includes Ti a Al b C c N 1-c Other than the ingredients.

[0143] The thickness of the fourth unit layer is preferably 0.3 μm or more and 9 μm or less. This further improves the wear resistance of the cutting tool. Furthermore, the thickness of the fourth unit layer is preferably 0.4 μm or more, more preferably 0.5 μm or more, and even more preferably 0.6 μm or more. Additionally, the thickness of the fourth unit layer is preferably 7 μm or less, more preferably 5 μm or less, and even more preferably 3 μm or less. Furthermore, the thickness of the fourth unit layer is preferably 0.4 μm or more and 7 μm or less, more preferably 0.5 μm or more and 5 μm or less, and even more preferably 0.6 μm or more and 3 μm or less.

[0144] Furthermore, the value of 'a' is preferably 0.3 or more and 0.95 or less, more preferably 0.35 or more and 0.9 or less, and even more preferably 0.4 or more and 0.85 or less.

[0145] Furthermore, the value of b is preferably 0.05 or more and 0.7 or less, more preferably 0.1 or more and 0.65 or less, and even more preferably 0.15 or more and 0.6 or less.

[0146] Furthermore, the value of c is preferably 0.01 or more and 0.9 or less, more preferably 0.03 or more and 0.85 or less, and even more preferably 0.05 or more and 0.7 or less.

[0147] <Other Layers>

[0148] Provided that the effect of this embodiment is not compromised, the above-described coating may also include other layers as described above. For example... Figures 6-8 As shown, other layers mentioned above may include, for example, the base layer 14, the intermediate layer 15, and the surface layer 16.

[0149] (Basal layer)

[0150] The coating in this embodiment may include a base layer. The base layer 14 is disposed between the substrate 11 and the layer closest to the substrate in the first layer 12 and the second layer 13. The base layer is composed of a first compound, which preferably consists of one or more elements selected from the group consisting of Group IV, Group V, Group VI elements of the periodic table, and aluminum, and one or more elements selected from the group consisting of carbon, nitrogen, boron, and oxygen. This further improves the wear resistance of cutting tools. Additionally, it also improves the adhesion between the coating and the substrate.

[0151] As a base layer, by placing a TiN layer, TiC layer, TiCN layer, TiBN layer, AlCrN layer, or TiAlN layer directly above the substrate, the adhesion between the substrate and the coating can be improved. The thickness of the base layer is preferably 0.1 μm or more and 20 μm or less. This further improves the wear resistance of the cutting tool. Furthermore, this results in the cutting tool exhibiting excellent resistance to chipping.

[0152] (Middle layer)

[0153] The coating in this embodiment may include an intermediate layer. The intermediate layer 15 is disposed between the first layer 12 and the second layer 13. The composition of the intermediate layer is preferably, for example, a TiAlN layer or a TiN layer. The thickness of the intermediate layer is preferably 0.01 μm or more and 0.2 μm or less.

[0154] (Surface layer)

[0155] The coating in this embodiment may include a surface layer. The surface layer 16 is the layer disposed on the surface side of the coating 40. However, sometimes a surface layer is not formed on the cutting edge. The surface layer 16 is composed of a second compound, which preferably consists of one or more elements selected from the group consisting of Group IV, Group V, Group VI elements of the periodic table, and aluminum, and one or more elements selected from the group consisting of carbon, nitrogen, boron, and oxygen. This further improves the wear resistance of the cutting tool.

[0156] The surface layer 16 can be a TiN layer or a TiAlN layer. The TiN layer has a clear, golden color, and therefore, if used as the surface layer 16, it offers the advantage of easy identification of the corners of the cutting tool after use (identification of used areas). By using a TiAlN layer as the surface layer 16, the oxidation resistance of the coating can be improved.

[0157] The thickness of the surface layer 16 is preferably 0.05 μm or more and 1 μm or less. This improves the adhesion between the surface layer 16 and the adjacent layers.

[0158] [Implementation Method 2: Method for Manufacturing a Cutting Tool]

[0159] The manufacturing method of the cutting tool according to Embodiment 1 will be described below. It should be noted that the following manufacturing method is an example, and the cutting tool of Embodiment 1 can also be manufactured by other methods.

[0160] The method for manufacturing the cutting tool involved in this embodiment includes:

[0161] The first process for preparing the aforementioned substrate (hereinafter sometimes simply referred to as the "first process"); and

[0162] The second process (hereinafter, sometimes simply referred to as the "second process") involves forming the aforementioned coating on the aforementioned substrate. Each process will be described below.

[0163] First step: Preparing the substrate

[0164] In the first step, the aforementioned substrate is prepared. As mentioned above, any substrate conventionally known as such can be used; any substrate can be employed. For example, a tool made of a cubic boron nitride sintered body with a shape conforming to the ISO standard DNGA150408 can be used.

[0165] Second process: Forming a coating on the substrate

[0166] In the second step, a coating is formed on the substrate. Furthermore, the second step includes a "first layer coating step" in which at least a portion of the surface of the substrate is covered by a first layer, and a "second layer coating step" in which at least a portion of the surface of the substrate is covered by a second layer. Either the first layer coating step or the second layer coating step can be performed first, as long as both steps are executed. Additionally, the second step may further include at least one of steps (i), (ii), and (iii) described later. Furthermore, the second step may also include an "other layer coating step" in which at least a portion of the surface of the substrate is covered by other layers.

[0167] In both the first and second layer covering processes, at least the tip portion of the surface of the substrate is covered using either the first or second layer. Furthermore, here, "covering with the first layer" or "covering with the second layer" includes both cases where the first or second layer covers the entire surface of the substrate and cases where a layer other than the first or second layer (a base layer) is disposed between the substrate surface and the first or second layer. Either the first or second layer covering process can be performed first.

[0168] The aforementioned first layer covering process may include a "first unit layer covering process" for forming a first unit layer in the first layer. The aforementioned first layer covering process may further include a "second unit layer covering process" for forming a second unit layer in the first layer, or a "third unit layer covering process" for forming a third unit layer in the first layer. The aforementioned second layer covering process may include a "fourth unit layer covering process" for forming a fourth unit layer in the second layer. The second process may include "other layer covering processes" for forming the aforementioned other layers.

[0169] As a method for covering at least a portion of the aforementioned substrate using a first layer, physical vapor deposition (PVD) can be cited as an example. The same applies to the first unit layer covering process, the second unit layer covering process, the third unit layer covering process, the second layer covering process, and the fourth unit layer covering process.

[0170] Physical vapor deposition methods include, for example, sputtering, ion plating, arc ion plating, and electron ion beam evaporation. In particular, if a cathode arc ion plating or sputtering method with a high ion rate of the raw material element is used, the substrate surface can be subjected to metal ion bombardment or gas ion bombardment treatment before the coating is formed, thus significantly improving the adhesion between the coating and the substrate, and is therefore preferred.

[0171] When forming a coating by arc ion plating, the following conditions can be cited as an example. For example, when forming a layer composed of TiN, a Ti target is used as the metal evaporation source, and N2 gas is used as the reaction gas. The substrate temperature is set to 400 to 550°C, and the gas pressure in the apparatus is set to 0.3 to 1.5 Pa.

[0172] By maintaining a substrate (negative) bias voltage of 10–150V and applying DC or pulsed DC current (frequency 20–50 kHz), an arc current of 80–150 A is supplied to the cathode electrode, generating metal ions from the arc-type evaporation source, thereby forming a TiN layer. During film formation, the tungsten filament also discharges (emission current of 30–45 A). This increases the number of ions in the plasma. An example of an apparatus used in arc ion plating is the AIP (trade name) manufactured by Kobe Steel Corporation.

[0173] When forming a coating by sputtering, the following conditions can be listed as an example. When forming a layer composed of TiN, a Ti target can be used as the metal evaporation source, and sputtering gases such as N2 gas, Ar gas, Kr gas, and Xe gas can be used as the reaction gas.

[0174] The inventors of this invention have conducted in-depth research and have discovered that the hardness difference between the first and second layers can be adjusted by performing at least any one of the following steps (i) to (iii). In particular, it has been discovered that even when the hardness difference between the first and second layers is outside the desired range under conventional film-forming conditions in terms of chemical composition, the hardness difference between the first and second layers can be easily adjusted by performing at least any one of the above steps (i) to (iii).

[0175] In step (i) above, the second layer is annealed for a certain period of time using a heater. This reduces the hardness of the second layer, allowing the hardness H2 to be adjusted to the range of 0.5 × H1 ≤ H2 ≤ 0.9 × H1. It should be noted that the heating rate in step (i) is, for example, 5°C / min or more and 10°C / min or less. Furthermore, the annealing temperature in step (i) is, for example, 400°C or more and 500°C or less. Furthermore, the annealing time in step (i) is, for example, 10 minutes or more and 60 minutes or less. Furthermore, the cooling rate in step (i) is, for example, 5°C / min or more and 10°C / min or less. Furthermore, the furnace pressure during cooling in step (i) is, for example, 1 Pa or more and 8 Pa or less.

[0176] In step (ii) above, the first layer or the second layer is subjected to ion bombardment treatment based on sputtering gas. This imparts compressive stress to the first layer or the second layer, thereby increasing the hardness of the ion-bombarded first layer or the second layer. It should be noted that the gas composition in step (ii) is, for example, Ar (100%), Kr (100%), or Xe (100%). Furthermore, the gas pressure in step (ii) is, for example, 1 Pa or more and 3 Pa or less. Furthermore, the bias voltage in step (ii) is, for example, -1000 V or more and -600 V or less. Furthermore, the processing time in step (ii) is, for example, 5 minutes or more and 60 minutes or less.

[0177] In step (iii) above, the first unit layer and the second unit layer or the third unit layer are alternately stacked. This generates strain on the lattice constants of the different layers, thus allowing the hardness of the first layer to be adjusted.

[0178] Furthermore, the inventors of this invention have conducted in-depth research and have discovered that by performing the following step (iv), the adhesion between the first layer and the second layer can be improved.

[0179] In the above process (iv), when switching between the second layer covering process and the first layer covering process, the bias voltage is adjusted as follows.

[0180] The case where the second layer coating process is performed first, followed by the first layer coating process, will be described. The bias voltage for the second layer coating process is set to A (V), and the bias voltage for the first layer coating process is set to B (V). First, the second layer coating process is performed with the bias voltage set to A (V). At the point when the thickness of the second layer reaches the desired thickness, while maintaining film formation conditions other than the bias voltage, the bias voltage is changed to be greater than A and less than B (V) when B > A, or greater than B and less than A (V) when A > B, and film formation is performed for 60–120 seconds. This process is referred to as process (iv-1). Next, the film formation conditions other than the bias voltage are changed to the first layer coating conditions, and the bias voltage is maintained in process (iv-1) for 60–120 seconds. This process is referred to as process (iv-2). Next, while maintaining film formation conditions other than the bias voltage, the bias voltage is changed to B (V), and the first layer coating process is performed. In this case, the above-mentioned step (iv) includes one or both of steps (iv-1) and steps (iv-2).

[0181] The following describes the case where a first layer coating process is performed first, followed by a second layer coating process. The bias voltage for the first layer coating process is set to B (V), and the bias voltage for the second layer coating process is set to A (V). First, the first layer coating process is performed with the bias voltage set to B (V). At the point when the thickness of the first layer reaches the desired thickness, while maintaining film formation conditions other than the bias voltage, the bias voltage is changed to be greater than A and less than B (V) when B > A, or greater than B and less than A (V) when A > B, and film formation is performed for 60–120 seconds. This process is referred to as process (iv-3). Next, the film formation conditions other than the bias voltage are changed to the second layer coating conditions, and the bias voltage is maintained in process (iv-3) for 60–120 seconds, and film formation is performed. This process is referred to as process (iv-4). Next, while maintaining film formation conditions other than the bias voltage, the bias voltage is changed to A (V), and the second layer coating process is performed. In this case, the above-mentioned step (iv) includes one or both of steps (iv-3) and steps (iv-4).

[0182] It should be noted that when the bias voltage B(V) of the first layer covering process is not greater than 20V and less than 60V, there is a tendency to make it difficult to obtain the desired hardness H1.

[0183] According to the above process (iv), the change in bias voltage when switching from the first layer coating process to the second layer coating process, and when switching from the second layer coating process to the first layer coating process, can be made smoother. Therefore, the deviation in orientation in the coating caused by the abrupt change in bias voltage during coating formation can be suppressed. As a result, I (200) / (I (200) +I (111) +I (220) ), I (111) / (I (200) +I (111) +I (220) ), and I (220) / (I (200) +I (111) +I (220) The orientation of either of them is dominant, therefore I (200) / (I (200) +I (111) +I (220) ), I (111) / (I (200) +I (111) +I (220) ), and I (220) / (I (200) +I (111) +I (220) At least one of the following can be 0.45 or higher. The inventors of this invention conducted in-depth research and discovered that by switching the bias voltage as described above, orientation deviations in the coating can be suppressed.

[0184] <Other layer covering processes>

[0185] In the second process described in this embodiment, in addition to the first layer covering process, the second layer covering process, and the annealing process described above, a "base layer covering process" for forming a base layer between the substrate and the first layer, an "intermediate layer covering process" for forming an intermediate layer between the first layer and the second layer, and a "surface layer covering process" for forming a surface layer on top of the second layer may also be performed. When forming the base layer, intermediate layer, and surface layer, these other layers can be formed using conventional methods. Specifically, for example, the other layers can be formed using the PVD method described above.

[0186] Other processes

[0187] In the manufacturing method described in this embodiment, in addition to the steps described above, a surface treatment step may also be performed, for example. Examples of surface treatment steps include surface treatment using a medium that supports diamond powder in an elastic material.

[0188] Example

[0189] The present invention will be described in detail below with reference to specific embodiments, but the present invention is not limited to these embodiments.

[0190] [Example 1]

[0191] Making Cutting Tools

[0192] [Sample No. 1-1 to Sample No. 1-15, Sample No. 1-17 to Sample No. 1-34, and Sample No. 1-101 to Sample No. 1-106]

[0193] The cutting tools for specimens No. 1-1 to No. 1-15, No. 1-17 to No. 1-34, and No. 1-101 to No. 1-106 are manufactured using the following manufacturing method.

[0194] <Substrate preparation process>

[0195] First, as a substrate preparation step, a cubic boron nitride sintered body tool (shape: JIS standard DNGA150408) is prepared as the substrate. Next, the substrate is placed at a predetermined position in the arc ion plating apparatus (manufactured by Kobe Steel Corporation, trade name: AIP).

[0196] <Process of forming a coating on a substrate>

[0197] Next, as a second coating process, a second layer is formed on the surface of the substrate using arc ion plating under the conditions described in Table 1. Specifically, this is performed by the following method: A target corresponding to the "composition" of the second layer described in Tables 3 and 4 below is used as the metal evaporation source. For example, if the composition of the second layer is TiAlN, a TiAl target is used as the metal evaporation source. Alternatively, if the composition is TiCN, TiC, or TiN, a Ti target is used as the metal evaporation source. N2 gas and / or methane gas are used as the reaction gas. The substrate temperature is set to 500°C, and the pressure within the apparatus is set to 1 Pa.

[0198] Next, as step (i), the surface of the second layer is annealed under the conditions specified in the "Annealing Temperature [°C] / Time [minutes]" column of Table 1. The furnace pressure during annealing is set to 2 Pa. A "-" in the "Annealing Temperature [°C] / Time [minutes]" column of Table 1 indicates that step (i) was not performed.

[0199] Next, as step (ii), ion bombardment treatment is performed under the conditions listed in the "Ion Bombardment" column of Table 1. Here, "Ar (800V)" means that the reaction gas is Ar gas and the bias voltage is 800V. The ion bombardment treatment time is set to 45 minutes, and the furnace pressure is set to 1 Pa. "-" in the "Ion Bombardment" column of Table 1 indicates that step (ii) was not performed.

[0200] Next, as step (iv), under conditions other than maintaining the bias voltage, the bias voltage is adjusted from the value of the bias voltage in the second layer coating step to the value of the bias voltage listed in the "Step (iv)" column of Table 1, and film deposition is performed for 60 seconds. For example, in sample 1-1, the bias voltage is adjusted from 30V (the bias voltage in the second layer coating step) to 33V (the bias voltage in step (iv)). Next, the film deposition conditions other than the bias voltage are changed to the first layer coating conditions shown below, and film deposition is performed for 60 seconds while maintaining the bias voltage.

[0201] Next, as the first layer coating process, under the conditions described in Table 1, an arc ion plating method is used to form the first layer on top of the second layer. Specifically, this is performed by the following method: A target corresponding to the "composition" of the first layer described in Tables 3 and 4 (described later) is used as the metal evaporation source. For example, if the composition of the first layer is TiAlN, a TiAl target is used as the metal evaporation source. Alternatively, for example, if the composition of the first layer is TiAlSiN, a TiAlSi target is used as the metal evaporation source. N2 gas is used as the reaction gas. The substrate temperature is set to 500°C, and the gas pressure within the apparatus is set to 4 Pa.

[0202] Table 1

[0203]

[0204] [Sample No. 1-16]

[0205] The cutting tools for specimens No. 1-16 were manufactured using the following manufacturing method.

[0206] <Substrate preparation process>

[0207] As a substrate preparation step, a substrate identical to that of the aforementioned sample No. 1-1 is prepared, and the substrate is placed at a predetermined position in the arc ion plating apparatus.

[0208] <Process of forming a coating on a substrate>

[0209] Next, as the first layer covering process, under the conditions described in Table 2, using the arc ion plating method, form the first layer on the above-mentioned substrate. Specifically, it is carried out by the following method. As the metal evaporation source, use the target corresponding to the "composition" of the first layer described in Table 3 below. That is, use a TiAl target as the metal evaporation source. Use N2 gas as the reaction gas. Set the substrate (base material) temperature to 500 °C and set the air pressure in the device to 2 Pa.

[0210] Next, as process (iv), while maintaining the conditions other than the bias voltage, adjust the bias voltage from the value of the bias voltage in the first layer covering process to the value of the bias voltage described in the "process (iv)" column of Table 2. Next, change the film-forming conditions other than the bias voltage to the following second layer covering conditions and perform film formation for 60 seconds while maintaining the bias voltage.

[0211] Next, as the second layer covering process, under the conditions described in Table 2, using the arc ion plating method, form the second layer on top of the above-mentioned first layer. Specifically, it is carried out by the following method. As the metal evaporation source, use the target corresponding to the "composition" of the second layer described in Table 3 and Table 4 below. That is, use a TiAl target as the metal evaporation source. Use N2 gas as the reaction gas. Set the substrate (base material) temperature to 500 °C and set the air pressure in the device to 2 Pa.

[0212] It should be noted that in order to manufacture the cutting tools of Specimen No. 1-16, processes (i) and (ii) were not performed.

[0213] Table 2

[0214]

[0215] "Characteristics Evaluation of Cutting Tools"

[0216] Using the cutting tools of Specimen No. 1-1 to Specimen No. 1-34 and Specimen No. 1-101 to Specimen No. 1-106 manufactured as described above, evaluate the respective characteristics of the cutting tools as follows. It should be noted that the cutting tools of Specimen No. 1-1 to Specimen No. 1-34 correspond to the embodiments, and the cutting tools of Specimen No. 1-101 to Specimen No. 1-106 correspond to the comparative examples.

[0217] <Measurement of x, y, z, a, b, and c>

[0218] For the cutting tools of Specimen No. 1-1 to Specimen No. 1-34 and Specimen No. 1-101 to Specimen No. 1-106, obtain the composition Ti of the first layer by the method described in Embodiment 1 xAl y M 1-x-y C z N 1-z The “x”, “y”, “z”, and the second layer Ti a Al b C c N 1-c The results are represented by "a", "b", and "c". The atomic ratios are recorded in the "Composition" section of Tables 3 and 4, respectively.

[0219]

[0220]

[0221] <Determination of the thickness of the first layer and the second layer>

[0222] For the cutting tools of samples No. 1-1 to No. 1-34 and samples No. 1-101 to No. 1-106, the thickness of the first layer was determined using the method described in Embodiment 1. The results were recorded in the "Thickness T1 [μm]" field of Tables 3 and 4, respectively. Furthermore, for the cutting tools of samples No. 1-1 to No. 1-34 and samples No. 1-101 to No. 1-106, the thickness of the second layer was determined using the method described in Embodiment 1. The results were recorded in the "Thickness T2 [μm]" field of Tables 3 and 4, respectively.

[0223] <Determination of the hardness H1 of the first layer and the hardness H2 of the second layer>

[0224] For the cutting tools of samples No. 1-1 to No. 1-34 and samples No. 1-101 to No. 1-106, the hardness H1 of the first layer was determined using the method described in Embodiment 1. The results are recorded in the "Hardness H1 [GPa]" field of Tables 3 and 4, respectively. Furthermore, for the cutting tools of samples No. 1-1 to No. 1-34 and samples No. 1-101 to No. 1-106, the hardness H2 of the second layer was determined using the method described in Embodiment 1. The results are recorded in the "Hardness H2 [GPa]" field of Tables 3 and 4, respectively.

[0225] (200) / (I (200) +I (111) +I (220) ), I (111) / (I (200) +I (111) +I (220) ), and I​(220) / (I (200) +I (111) +I (220) The determination of )

[0226] For the cutting tools of samples No. 1-1 to No. 1-34 and samples No. 1-101 to No. 1-106, the coating I was determined by the method described in Embodiment 1. (200) / (I (200) +I (111) +I (220) The results obtained are recorded in Tables 3 and 4, respectively, under "R". (200) "In addition, for the cutting tools of samples No.1-1 to No.1-34 and samples No.1-101 to No.1-106, the coating I was determined by the method described in Embodiment 1." (111) / (I (200) +I (111) +I (220) The results obtained are recorded in Tables 3 and 4, respectively, under "R". (111) "In addition, for the cutting tools of samples No.1-1 to No.1-34 and samples No.1-101 to No.1-106, the coating I was determined by the method described in Embodiment 1." (220) / (I (200) +I (111) +I (220) The results obtained are recorded in Tables 3 and 4, respectively, under "R". (220) "In one item."

[0227] Cutting Test

[0228] The following cutting tests were conducted using the cutting tools of specimens No.1-1 to No.1-34 and specimens No.1-101 to No.1-106, which were prepared as described above.

[0229] For the cutting tools of specimens No. 1-1 to No. 1-34 and specimens No. 1-101 to No. 1-106, the workpiece was cut under the following cutting conditions. Then, at a time point when the cutting distance reached 50 m, the cutting tools and workpiece were temporarily separated. After 3 minutes following the separation, the workpiece was cut again under the following cutting conditions. This process was repeated until the cutting distance reached 3 km. Next, the maximum wear on the flank face of the cutting tool at the time point when the cutting distance reached 3 km was measured as the maximum wear. A smaller maximum wear indicates a longer tool life, even under high-load cutting. Furthermore, a maximum wear of 290 μm or less indicates a longer tool life, even under high-load cutting. The maximum wear is recorded in the "Maximum Wear [μm]" field of Tables 3 and 4.

[0230] (Cutting conditions)

[0231] Workpiece to be cut: High-hardness steel SUJ2 (HRC62) (diameter 85mm × length 200mm)

[0232] Cutting speed: V = 100 m / min.

[0233] Feed rate: f = 0.2 mm / rev.

[0234] Incision: ap = 0.5mm

[0235] Wet / Dry: Wet

[0236] This cutting condition is equivalent to high-load cutting of quenched steel (a high-hardness material).

[0237] <Results>

[0238] Samples No. 1-1 to No. 1-34 correspond to the Examples. Samples No. 1-101 to No. 1-106 correspond to the Comparative Examples. The results in Tables 3 and 4 confirm that the cutting tools of Samples No. 1-1 to No. 1-34, corresponding to the Examples, have a longer tool life than those of Samples No. 1-101 to No. 1-106, corresponding to the Comparative Examples, even under high-load cutting conditions such as cutting high-hardness materials like quenched steel. It is speculated that this is because the first layer of the coating in the cutting tools of Samples No. 1-1 to No. 1-34 has high hardness and good wear resistance. Furthermore, the coating includes both the first and second layers, resulting in good resistance to chipping and peeling. This prevents damage to the coating during cutting and suppresses wear originating from that point.

[0239] [Example 2]

[0240] Making Cutting Tools

[0241] [Sample No. 2-1 to Sample No. 2-42]

[0242] The cutting tools for specimens No. 2-1 to No. 2-42 were manufactured using the following manufacturing method.

[0243] <Substrate preparation process>

[0244] As a substrate preparation step, a substrate identical to that of the aforementioned samples No.1-1 to No.1-15, No.1-17 to No.1-34, and No.1-101 to No.1-106 is prepared, and the substrate is placed at a predetermined position in the arc ion plating apparatus.

[0245] <Process of forming a coating on a substrate>

[0246] As the second coating process, except that the conditions described in Tables 5 and 6 are followed and the following targets are used as the metal evaporation source, an arc ion plating method is used to form a second layer on the substrate under the same conditions as those for Samples No. 1-1 to No. 1-15, Samples No. 1-17 to No. 1-34, and Samples No. 1-101 to No. 1-106. As the metal evaporation source, a target corresponding to the "composition" of the second layer described in Table 7 is used. Specifically, when the composition of the second layer is TiAlN, a TiAl target is used as the metal evaporation source. Alternatively, when the composition is TiCN or TiN, a Ti target is used as the metal evaporation source.

[0247] Next, as step (iv), the bias voltage is adjusted from the value of the bias voltage in the second layer covering step to the value of the bias voltage recorded in the "Step (iv)" column of Tables 5 and 6, and film deposition is performed for 60 seconds. Then, the film deposition conditions other than the bias voltage are changed to the first layer covering conditions shown below, and film deposition is performed for 60 seconds while maintaining the bias voltage. It should be noted that steps (i) and (ii) are not performed.

[0248] Next, as the first layer coating process, under the conditions described in Tables 5 and 6, the first unit layer coating process and the second unit layer coating process are alternately performed using arc ion plating, thereby forming the first layer on the surface of the second layer. Specifically, this is performed by the following method: As the metal evaporation source, a target corresponding to the "composition" of the first layer described in Tables 7 and 8 (described later) is used. That is, when the composition of the first unit layer is TiAlN, a TiAl target is used as the metal evaporation source. Alternatively, for example, when the composition of the first unit layer is TiAlSiN, a TiAlSi target is used as the metal evaporation source. Additionally, when the composition of the second unit layer is AlCrN, an AlCr target is used as the metal evaporation source. Additionally, when the composition of the second unit layer is CrN, a Cr target is used as the metal evaporation source. N2 gas is used as the reaction gas. The substrate temperature is set to 500°C, and the gas pressure inside the apparatus is set to 4 Pa. It should be noted that in both the first unit layer coating process and the second unit layer coating process, the first unit layer coating process is performed first, and the second unit layer coating process is performed last.

[0249] Table 5

[0250]

[0251] Table 6

[0252]

[0253] Evaluation of Cutting Tool Characteristics

[0254] For the cutting tools of specimens No. 2-1 to No. 2-42 prepared as described above, the composition Ti of the first unit layer was determined by measurement using the same method as in Example 1. x Al y M 1-x-y C z N 1-z The "x", "y", "z", "thickness of the first unit layer", and composition of the second unit layer Al are mentioned. m Cr 1-m "m" in N, "thickness of the second unit layer", and the composition of the second layer Ti a Al b C c N 1-c The symbols “a”, “b”, “c”, “thickness of the first layer”, “thickness of the second layer”, “hardness of the first layer H1”, “hardness of the second layer H2”, and “I” are used to indicate the layer thickness. (200) / (I (200) +I (111) +I (220) ) (“R (200)"), "I (111) / (I (200) +I (111) +I (220) ) (“R (111) "), and "I (220) / (I (200) +I (111) +I (220) ) (“R (220) The results are recorded in Tables 7 and 8, respectively. The relationship between "thickness of the first unit layer", "thickness of the second unit layer" and "thickness of the first layer" is as follows. For example, in sample 2-1, a first unit layer with a thickness of 15 nm and a second unit layer with a thickness of 10 nm are alternately stacked to form the first layer, and the thickness T1 of the first layer is 2.5 μm. It should be noted that the cutting tools of samples No. 2-1 to No. 2-42 are equivalent to the examples.

[0255]

[0256]

[0257] Cutting Test

[0258] For the cutting tools of specimens No. 2-1 to No. 2-42 prepared as described above, a "cutting test" was performed using the same method as in Example 1, thereby determining the "maximum wear amount". The results obtained are recorded in the "maximum wear amount [μm]" field of Tables 7 and 8, respectively.

[0259] <Results>

[0260] Samples No. 2-1 to No. 2-42 are equivalent to the Examples. The results in Tables 7 and 8 confirm that the cutting tools of Samples No. 2-1 to No. 2-42, which are equivalent to the Examples, have a long tool life even under high-load cutting conditions such as cutting high-hardness materials like hardened steel. It is presumably because, similar to Example 1, in the cutting tools of Samples No. 2-1 to No. 2-42, the first layer of the coating has high hardness and good wear resistance. Furthermore, the coating includes both the first and second layers, resulting in good resistance to chipping and peeling. This prevents damage to the coating during cutting and suppresses wear originating from that point.

[0261] [Example 3]

[0262] Making Cutting Tools

[0263] [Sample No. 3-1 to Sample No. 3-43 and Sample No. 3-101]

[0264] The cutting tools for specimens No. 3-1 to No. 3-43 and No. 3-101 were manufactured using the following manufacturing method.

[0265] <Substrate preparation process>

[0266] As a substrate preparation step, a substrate identical to that of the aforementioned samples No.1-1 to No.1-15, No.1-17 to No.1-34, and No.1-101 to No.1-106 is prepared, and the substrate is placed at a predetermined position in the arc ion plating apparatus.

[0267] <Process of forming a coating on a substrate>

[0268] As the second coating process, except that it is performed under the conditions described in Tables 9 and 10 and the following targets are used as the metal evaporation source, an arc ion plating method is used to form a second layer on the surface of the substrate under the same conditions as those for Samples No. 1-1 to No. 1-15, Samples No. 1-17 to No. 1-34, and Samples No. 1-101 to No. 1-106. As the metal evaporation source, a target corresponding to the "composition" of the second layer described in Tables 11 and 12 (described later) is used. Specifically, when the composition of the second layer is TiAlN or TiAlC, a TiAl target is used as the metal evaporation source. Furthermore, when the composition of the second layer is TiCN, TiC, or TiN, a Ti target is used as the metal evaporation source.

[0269] Next, in order to prepare the cutting tool for sample No. 3-30, as step (i), the surface of the second layer was annealed at the temperature conditions listed in the "Annealing Temperature [°C]" column of Tables 9 and 10. A "-" in the "Annealing Temperature [°C]" column of Tables 9 and 10 indicates that step (i) was not performed.

[0270] Next, as step (iv), the bias voltage in the second layer coating step is adjusted to the bias voltage recorded in the "Step (iv)" column of Tables 9 and 10, and film deposition is performed for 60 seconds. Then, the film deposition conditions other than the bias voltage are changed to the first layer coating conditions shown below, and film deposition is performed for 60 seconds while maintaining the bias voltage. It should be noted that step (ii) is not performed.

[0271] Next, as the first layer coating process, under the conditions described in Tables 9 and 10, the first unit layer coating process and the third unit layer coating process are performed alternately using arc ion plating, thereby forming the first layer on the surface of the second layer. Specifically, this is performed by the following method. As the metal evaporation source, a target corresponding to the "composition" of the first layer described in Tables 11 and 12 (described later) is used. That is, when the composition of the first unit layer is TiAlN, a TiAl target is used as the metal evaporation source. Alternatively, for example, when the composition of the first unit layer is TiAlSiN, a TiAlSi target is used as the metal evaporation source. Additionally, when the composition of the third unit layer is TiAlN, a TiAl target is used as the metal evaporation source. N2 gas is used as the reaction gas. The substrate temperature is set to 500°C, and the gas pressure inside the apparatus is set to 4 Pa. It should be noted that in the first unit layer coating process and the third unit layer coating process, the first unit layer coating process is performed first, and the third unit layer coating process is performed last.

[0272] Table 9

[0273]

[0274] Table 10

[0275]

[0276] Evaluation of Cutting Tool Characteristics

[0277] For the cutting tools of samples No. 3-1 to No. 3-43 and samples No. 3 to 101 prepared as described above, the composition Ti of the first unit layer was determined by measurement using the same method as in Example 1. x Al y M 1-x-y C z N 1-z The "x", "y", "z", "thickness of the first unit layer", and composition of the third unit layer Ti are mentioned. n Al 1-n The "n" in N, the thickness of the third unit layer, and the composition of the second layer Ti a Al b C c N 1-c The symbols “a”, “b”, “c”, “thickness of the first layer”, “thickness of the second layer”, “hardness of the first layer H1”, “hardness of the second layer H2”, and “I” are used to indicate the layer thickness. (200) / (I (200) +I (111) +I (220) ) (“R (200) "), "I (111) / (I (200) +I (111) +I (220) ) (“R (111) "), and "I (220) / (I (200) +I (111) +I (220) ) (“R (220) The results are recorded in Tables 11 and 12, respectively. The relationship between "thickness of the first unit layer", "thickness of the third unit layer" and "thickness of the first layer" is as follows. For example, in sample 3-1, a first unit layer with a thickness of 10 nm and a third unit layer with a thickness of 15 nm are alternately stacked to form the first layer, and the thickness T1 of the first layer is 2.5 μm. It should be noted that the cutting tools of samples No. 3-1 to No. 3-43 are equivalent to the examples, and the cutting tool of sample No. 3-101 is equivalent to the comparative example.

[0278]

[0279]

[0280] Cutting Test

[0281] For the cutting tools of specimens No. 3-1 to No. 3-43 and No. 3-101 prepared as described above, a "cutting test" was performed using the same method as in Example 1 to determine the "maximum wear amount". The results are recorded in the "maximum wear amount [μm]" field of Tables 11 and 12, respectively.

[0282] <Results>

[0283] Samples No. 3-1 to No. 3-43 correspond to the Examples. Sample No. 3-101 corresponds to the Comparative Example. The results in Tables 11 and 12 confirm that the cutting tools of Samples No. 3-1 to No. 3-43, corresponding to the Examples, have a longer tool life than Sample No. 3-101, corresponding to the Comparative Example, even under high-load cutting conditions such as cutting high-hardness materials like quenched steel. It is presumably because, similar to Example 1, in the cutting tools of Samples No. 3-1 to No. 3-43, the first layer of the coating has high hardness and good wear resistance. Furthermore, the coating includes both the first and second layers, resulting in good resistance to chipping and peeling. This prevents damage to the coating during cutting and suppresses wear originating from that point.

[0284] [Example 4]

[0285] Making Cutting Tools

[0286] [Sample No. 4-1 to Sample No. 4-28]

[0287] The cutting tools for specimens No. 4-1 to No. 4-28 were manufactured using the following manufacturing method.

[0288] <Substrate preparation process>

[0289] As a substrate preparation step, a substrate identical to that of the aforementioned samples No.1-1 to No.1-15, No.1-17 to No.1-34, and No.1-101 to No.1-106 is prepared, and the substrate is placed at a predetermined position in the arc ion plating apparatus.

[0290] <Process of forming a coating on a substrate>

[0291] As the second coating process, except that it is performed under the conditions described in Table 13 and the following targets are used as the metal evaporation source, an arc ion plating method is used to form a second layer on the surface of the substrate under the same conditions as those for Samples No. 1-1 to No. 1-15, Samples No. 1-17 to No. 1-34, and Samples No. 1-101 to No. 1-106. As the metal evaporation source, a target corresponding to the "composition" of the second layer described in Table 14 is used. Specifically, when the composition of the second layer is TiAlN or TiAlC, a Ti target and an Al target are used as the metal evaporation source. Furthermore, when the composition of the second layer is TiCN or TiN, a Ti target is used as the metal evaporation source.

[0292] Next, as step (iv), the bias voltage is adjusted from the value of the bias voltage in the second layer covering step to the value of the bias voltage recorded in the "Step (iv)" column of Table 13, and film deposition is performed for 60 seconds. Then, the film deposition conditions other than the bias voltage are changed to the first layer covering conditions shown below, and film deposition is performed for 60 seconds while maintaining the bias voltage. It should be noted that steps (i) and (ii) are not performed.

[0293] Next, as the first layer coating process, under the conditions described in Table 13, the first unit layer coating process and the second unit layer coating process are performed alternately using arc ion plating, thereby forming the first layer on the surface of the second layer. Specifically, this is performed by the following method: As the metal evaporation source, a target corresponding to the "composition" of the first layer described in Table 14 (described later) is used. That is, when the composition of the first unit layer is TiAlN, a TiAl target is used as the metal evaporation source. Alternatively, for example, when the composition of the first unit layer is TiAlSiN, a TiAlSi target is used as the metal evaporation source. Additionally, when the composition of the second unit layer is AlCrN, an AlCr target is used as the metal evaporation source. Additionally, when the composition of the second unit layer is CrN, a Cr target is used as the metal evaporation source. N2 gas is used as the reaction gas. The substrate temperature is set to 500°C, and the gas pressure in the apparatus is set to 4 Pa. It should be noted that in both the first unit layer coating process and the second unit layer coating process, the first unit layer coating process is performed first, and the second unit layer coating process is performed last.

[0294] Next, the series of processes consisting of the second layer coating process and the first layer coating process described above will be performed as many times as listed in the "Number of repetitions of the second layer coating process to the first layer coating process" item in Table 13. For example, in sample No. 4-1, the series of processes consisting of the second layer coating process and the first layer coating process described above will be repeated three times. That is, the coating of sample No. 4-1 is alternately laminated with the second layer and the first layer, and contains three layers of the second layer and three layers of the first layer.

[0295] Table 13

[0296]

[0297] Evaluation of Cutting Tool Characteristics

[0298] For the cutting tools of specimens No. 4-1 to No. 4-28 prepared as described above, the composition Ti of the first unit layer was determined by measurement using the same method as in Example 1. x Al y M 1-x-y C z N 1-z The "x", "y", "z", "thickness of the first unit layer", and composition of the second unit layer Al are mentioned. m Cr 1-m "m" in N, "thickness of the second unit layer", and the composition of the second layer Ti a Al b C c N 1-cThe terms "a", "b", "c", "thickness of the first layer", "thickness of the second layer", "hardness of the first layer H1", "hardness of the second layer H2", and "I" are used to indicate the layer thickness. (200) / (I (200) +I (111) +I (220) ) (“R (200) "), "I (111) / (I (200) +I (111) +I (220) ) (“R (111) "), and "I (220) / (I (200) +I (111) +I (220) ) (“R (220) The results are recorded in Table 14. Here, "thickness of the first unit layer" refers to the thickness of the first unit layer of a layer, "thickness of the second unit layer" refers to the thickness of the second unit layer of a layer, "thickness of the first layer" refers to the thickness of the first layer of a layer, and "thickness of the second layer" refers to the thickness of the second layer of a layer. For example, in sample 4-1, a first unit layer with a thickness of 15 nm and a second unit layer with a thickness of 10 nm are alternately stacked to form a first layer, the thickness of which T1 is 0.5 μm. There are three of these first layers and three of the second layers with a thickness T2 of 0.5 μm in the coating. It should be noted that the cutting tools of samples No. 4-1 to No. 4-28 are equivalent to the examples.

[0299]

[0300] Cutting Test

[0301] For the cutting tools of specimens No. 4-1 to No. 4-28 prepared as described above, a "cutting test" was performed using the same method as in Example 1 to determine the "maximum wear amount". The results are recorded in the "maximum wear amount [μm]" field of Table 14.

[0302] <Results>

[0303] Samples No. 4-1 to No. 4-28 are equivalent to the Examples. The results in Table 14 confirm that the cutting tools of Samples No. 4-1 to No. 4-28, which are equivalent to the Examples, have a long tool life even under high-load cutting conditions such as cutting high-hardness materials like hardened steel. It is presumably because, similar to Example 1, in the cutting tools of Samples No. 4-1 to No. 4-28, the first layer of the coating has high hardness and good wear resistance. Furthermore, the coating includes both the first and second layers, resulting in good resistance to chipping and peeling. This prevents damage to the coating during cutting and suppresses wear originating from that point.

[0304] [Example 5]

[0305] Making Cutting Tools

[0306] [Sample No. 5-1 to Sample No. 5-28]

[0307] The cutting tools for specimens No. 5-1 to No. 5-28 were manufactured using the following manufacturing method.

[0308] <Substrate preparation process>

[0309] As a substrate preparation step, a substrate identical to that of the aforementioned samples No.1-1 to No.1-15, No.1-17 to No.1-34, and No.1-101 to No.1-106 is prepared, and the substrate is placed at a predetermined position in the arc ion plating apparatus.

[0310] <Process of forming a coating on a substrate>

[0311] As the second coating process, except that it is performed under the conditions described in Table 15 and the following targets are used as the metal evaporation source, an arc ion plating method is used to form a second layer on the surface of the substrate under the same conditions as those for Samples No. 1-1 to No. 1-15, Samples No. 1-17 to No. 1-34, and Samples No. 1-101 to No. 1-106. As the metal evaporation source, a target corresponding to the "composition" of the second layer described in Table 16 is used. Specifically, when the composition of the second layer is TiAlN or TiAlC, a TiAl target is used as the metal evaporation source. Furthermore, when the composition of the second layer is TiN, a Ti target is used as the metal evaporation source.

[0312] Next, as step (iv), the bias voltage is adjusted from the value of the bias voltage in the second layer covering step to the value of the bias voltage recorded in the "Step (iv)" column of Table 15, and film deposition is performed for 60 seconds. Then, the film deposition conditions other than the bias voltage are changed to the first layer covering conditions shown below, and film deposition is performed for 60 seconds while maintaining the bias voltage. It should be noted that steps (i) and (ii) are not performed.

[0313] Next, as the first layer coating process, under the conditions described in Table 15, the first unit layer coating process and the third unit layer coating process are performed alternately using arc ion plating, thereby forming the first layer on the surface of the second layer. Specifically, this is performed by the following method. As the metal evaporation source, a target corresponding to the "composition" of the first layer described in Table 16 (described later) is used. That is, when the composition of the first unit layer is TiAlN, a TiAl target is used as the metal evaporation source. Alternatively, for example, when the composition of the first unit layer is TiAlSiN, a TiAlSi target is used as the metal evaporation source. Additionally, when the composition of the third unit layer is TiAlN, a TiAl target is used as the metal evaporation source. Additionally, when the composition of the third unit layer is AlN, an Al target is used as the metal evaporation source. N2 gas is used as the reaction gas. The substrate temperature is set to 500°C, and the gas pressure inside the apparatus is set to 4 Pa. It should be noted that in the first unit layer coating process and the third unit layer coating process, the first unit layer coating process is performed first, and the third unit layer coating process is performed last.

[0314] Next, as step (iii), the series of steps consisting of the second layer covering step to the first layer covering step described above are performed the number of times listed in the "Number of repetitions of the second layer covering step to the first layer covering step" item in Table 15. For example, in sample No. 5-1, the series of steps consisting of the second layer covering step to the first layer covering step described above are repeated three times. That is, the coating of sample No. 5-1 is alternately laminated with the second layer and the first layer, and contains three layers of the second layer and three layers of the first layer.

[0315] Table 15

[0316]

[0317] Evaluation of Cutting Tool Characteristics

[0318] For the cutting tools of specimens No. 5-1 to No. 5-28 prepared as described above, the composition Ti of the first unit layer was determined by measurement using the same method as in Example 1. x Al y M 1-x-y Cz N 1-z The "x", "y", "z", "thickness of the first unit layer", and composition of the third unit layer Ti are mentioned. n Al 1-n "n" in N, "thickness of the second unit layer", and the composition of the second layer Ti a Al b C c N 1-c The terms "a", "b", "c", "thickness of the first layer", "thickness of the second layer", "hardness of the first layer H1", "hardness of the second layer H2", and "I" are used to indicate the layer thickness. (200) / (I (200) +I (111) +I (220) ) "I (111) / (I (200) +I (111) +I (220) )” and “I” (220) / (I (200) +I (111) +I (220) The results are recorded in Table 16. Here, "thickness of the first unit layer" refers to the thickness of the first unit layer of a layer, "thickness of the third unit layer" refers to the thickness of the third unit layer of a layer, "thickness of the first layer" refers to the thickness of the first layer of a layer, and "thickness of the second layer" refers to the thickness of the second layer of a layer. For example, in sample No. 5-1, a first unit layer with a thickness of 10 nm and a second unit layer with a thickness of 15 nm are alternately stacked to form a first layer with a thickness T1 of 0.5 μm. There are three layers of this first layer and three layers of the second layer with a thickness T2 of 0.5 μm in the coating. It should be noted that the cutting tools of samples No. 5-1 to No. 5-28 are equivalent to the examples.

[0319]

[0320] Cutting Test

[0321] For the cutting tools of specimens No. 5-1 to No. 5-28 prepared as described above, a "cutting test" was performed using the same method as in Example 1, thereby determining the "maximum wear amount". The results obtained are recorded in the "maximum wear amount [μm]" field of Table 16.

[0322] <Results>

[0323] Samples No. 5-1 to No. 5-28 are equivalent to the Examples. The results in Table 16 confirm that the cutting tools of Samples No. 5-1 to No. 5-28, which are equivalent to the Examples, have a long tool life even under high-load cutting conditions such as cutting high-hardness materials like hardened steel. It is presumably because, similar to Example 1, in the cutting tools of Samples No. 5-1 to No. 5-28, the first layer of the coating has high hardness and good wear resistance. Furthermore, the coating includes both the first and second layers, resulting in good resistance to chipping and peeling. This prevents damage to the coating during cutting and suppresses wear originating from that point.

[0324] The embodiments and examples of this disclosure have been described above, but it is also intended from the outset that the above-described embodiments and examples may be appropriately combined or modified.

[0325] The embodiments and examples disclosed herein should be considered exemplary in all respects, and not restrictive. The scope of the invention is defined not by the foregoing embodiments and examples, but by the claims, and is intended to include all modifications equivalent to and within the scope of the claims.

[0326] Explanation of reference numerals in the attached figures

[0327] 1: Rake face; 2: Back face; 3: Tip edge; 10: Cutting tool; 11: Substrate; 12: First layer; 13: Second layer; 14: Base layer; 15: Intermediate layer; 16: Surface layer; 40: Coating; 121: First unit layer; 122: Second unit layer; 123: Third unit layer; 131: Fourth unit layer; A1 and A2: X-ray diffraction peaks from the (200) plane.

Claims

1. A cutting tool comprising a substrate and a coating disposed on the substrate, wherein, The coating comprises a first layer and a second layer. The hardness H1 of the first layer is above 25 GPa and below 40 GPa. The hardness H2 of the second layer satisfies 0.5×H1≤H2≤0.9×H1. X-ray diffraction intensity I relative to the (200) plane of the coating （200） X-ray diffraction intensity I of plane (111) （111） X-ray diffraction intensity I of plane (220) （220） The total of the I （200） The ratio I （200） / (I （200） +I （111） +I （220） ), Relative to the total of the I （111） The ratio I （111） / (I （200） +I （111） +I （220） ),as well as Relative to the total of the I （220） The ratio I （220） / (I （200） +I （111） +I （220） At least one of the following is 0.45 or higher: The first layer comprises a first unit layer. The first unit layer consists of Ti x Al y M 1-x-y C z N 1-z constitute, M is an element selected from the group consisting of zirconium, hafnium, elements of Group 5 of the periodic table, elements of Group 6 of the periodic table, silicon, boron, and yttrium. The x value is greater than 0.20 and less than 0.

99. The value of y is greater than or equal to 0.01 and less than or equal to 0.

80. The 1-xy is greater than 0.01 and less than 0.

20. The z is greater than 0 and less than 1.

0. The first layer also includes a second unit layer. The second unit layer consists of Al m Cr 1-m N constitutes, The value of m is greater than 0 and less than 0.

8. The thickness of the first unit layer is greater than 5 nm and less than 50 nm. The thickness of the second unit layer is greater than 5 nm and less than 50 nm. The first unit layer and the second unit layer are stacked alternately. The second layer contains a fourth unit layer. The fourth unit layer is composed of Ti a Al b C c N 1-c constitute, The value of a is greater than 0.2 and less than 1.

0. The value of b is greater than 0 and less than 0.

8. The value of c is greater than or equal to 0 and less than or equal to 1.

0.

2. A cutting tool comprising a substrate and a coating disposed on the substrate, wherein, The coating comprises a first layer and a second layer. The hardness H1 of the first layer is above 25 GPa and below 40 GPa. The hardness H2 of the second layer satisfies 0.5×H1≤H2≤0.9×H1. X-ray diffraction intensity I relative to the (200) plane of the coating （200） X-ray diffraction intensity I of plane (111) （111） X-ray diffraction intensity I of plane (220) （220） The total of the I （200） The ratio I （200） / (I （200） +I （111） +I （220） ), Relative to the total of the I （111） The ratio I （111） / (I （200） +I （111） +I （220） ),as well as Relative to the total of the I （220） The ratio I （220） / (I （200） +I （111） +I （220） At least one of the following is 0.45 or higher: The first layer comprises a first unit layer. The first unit layer consists of Ti x Al y M 1-x-y C z N 1-z constitute, M is an element selected from the group consisting of zirconium, hafnium, elements of Group 5 of the periodic table, elements of Group 6 of the periodic table, silicon, boron, and yttrium. The x value is greater than 0.20 and less than 0.

99. The value of y is greater than or equal to 0.01 and less than or equal to 0.

80. The 1-xy is greater than 0.01 and less than 0.

20. The z is greater than 0 and less than 1.

0. The first layer also includes a third unit layer. The third unit layer is composed of Ti 1-n Al n N constitutes, The n is greater than or equal to 0 and less than or equal to 0.

8. The thickness of the first unit layer is greater than 5 nm and less than 50 nm. The thickness of the third unit layer is greater than 5 nm and less than 50 nm. The first unit layer and the third unit layer are stacked alternately. The second layer contains a fourth unit layer. The fourth unit layer is composed of Ti a Al b C c N 1-c constitute, The value of a is greater than 0.2 and less than 1.

0. The value of b is greater than 0 and less than 0.

8. The value of c is greater than or equal to 0 and less than or equal to 1.

0.

3. The cutting tool according to claim 1 or 2, wherein, The thickness T1 of the first layer is greater than 0.2 μm and less than 10 μm.

4. The cutting tool according to claim 1 or 2, wherein, The thickness T2 of the second layer is greater than 0.2 μm and less than 10 μm.

5. The cutting tool according to claim 1 or 2, wherein, The ratio of the thickness T1 of the first layer to the thickness T2 of the second layer, T1 / T2, is greater than 0.02 and less than 50.

Images