Cutting tools

Abstract

A cutting tool includes a substrate and a hard layer disposed on the substrate. The hard layer comprises a first unit layer and a second unit layer, wherein the first unit layer and the second unit layer are alternately stacked in one or more layers. The thickness of the first unit layer is 2 nm or more and 100 nm or less, and the thickness of the second unit layer is 2 nm or more and 100 nm or less. The first unit layer is made of Ti. a Al b B c The compound shown in N is composed of the second unit layer, which is made of Ti. d Al e B f The compound represented by N is composed of the above Ti. a Al b B c The atomic ratio 'a' of titanium in N is greater than 0.25 and less than 0.45. The aforementioned Ti... a Al b B c The atomic ratio of aluminum in N is greater than or equal to 0.55 and less than 0.75. The above-mentioned Ti... a Al b B c The atomic ratio c of boron in N is greater than 0 and less than 0.1, and the total of the above atomic ratios a, b, and c is 1. The above Ti... d Al e B f The atomic ratio d of titanium in N is greater than 0.35 and less than 0.55. The above-mentioned Ti d Al e B f The atomic ratio of aluminum in N is greater than 0.45 and less than 0.65, and the above-mentioned Ti d Al e B f The atomic ratio f of boron in N is greater than 0 and less than 0.1. The total of the above atomic ratios d, e, and f is 1. The above atomic ratios a and d satisfy 0.05 ≤ d - a ≤ 0.2. The above atomic ratios b and e satisfy 0.05 ≤ b - e ≤ 0.2.

Description

Technical Field

[0001] This disclosure relates to cutting tools. Background Technology

[0002] Cutting tools with a coating on a substrate have been used for a long time. For example, Japanese Patent Application Publication No. 2011-224715 (Patent Document 1) discloses a surface-coated cutting tool in which a hard coating layer composed of Al and Ti composite nitride with a thickness of 0.8 to 5.0 μm is deposited on the surface of a tool substrate made of tungsten carbide-based cemented carbide or titanium carbonitride-based cermet. The hard coating layer is characterized by an alternating stacked structure of thin layer A and thin layer B. Thin layer A is composed of granular crystal structure of Al and Ti composite nitride, and thin layer B is composed of columnar crystal structure. Thin layer A and thin layer B each have a thickness of 0.05 to 2 μm. Furthermore, the average crystal grain size of the granular crystal constituting thin layer A is 30 nm or less, and the average crystal grain size of the columnar crystal constituting thin layer B is 50 to 500 nm.

[0003] Japanese Patent Application Publication No. 2017-193004 (Patent Document 2) discloses a surface-coated cutting tool comprising a substrate and a coating formed on the surface of the substrate. The coating includes alternating layers, each alternating layer comprising a first layer having a first composition and a second layer having a second composition. The alternating layers are formed by alternatingly stacking one or more layers of the first and second compositions. The thicknesses of the first and second layers are 2 nm or more and 100 nm or less, respectively. The first composition is composed of Ti. a Al b Si c N(0.25≤a≤0.45, 0.55≤b≤0.75, 0≤c≤0.1, a+b+c=1) represents the second component, denoted by Ti. d Al e Si f N(0.35≤d≤0.55, 0.45≤e≤0.65, 0≤f≤0.1, d+e+f=1) means that the first component and the second component satisfy 0.05≤da≤0.2 and 0.05≤be≤0.2.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2011-224715

[0007] Patent Document 2: Japanese Patent Application Publication No. 2017-193004 Summary of the Invention

[0008] The cutting tool disclosed herein comprises a substrate and a hard layer disposed on the substrate, wherein,

[0009] The aforementioned hard layer comprises a first unit layer and a second unit layer.

[0010] In the aforementioned hard layer, the first unit layer and the second unit layer are alternately stacked one or more times.

[0011] The thickness of the first unit layer is greater than 2 nm and less than 100 nm.

[0012] The thickness of the aforementioned second unit layer is greater than 2 nm and less than 100 nm.

[0013] The first unit layer mentioned above consists of Ti a Al b B c The compound represented by N is composed of...

[0014] The aforementioned second unit layer consists of Ti d Al e B f The compound represented by N is composed of...

[0015] The above Ti a Al b B c The atomic ratio of titanium in N is greater than 0.25 and less than 0.45.

[0016] The above Ti a Al b B c The atomic ratio of aluminum in N is greater than or equal to 0.55 and less than 0.75.

[0017] The above Ti a Al b B c The atomic ratio of boron in nitrogen (N) is greater than 0 and less than 0.1.

[0018] The total of the above atomic ratios a, b, and c is 1.

[0019] The above Ti d Al e B f The atomic ratio of titanium in nitrogen (d) is greater than 0.35 and less than 0.55.

[0020] The above Ti d Al e B f The atomic ratio of aluminum in nitrogen (N) is greater than 0.45 and less than 0.65.

[0021] The above Tid Al e B f The atomic ratio f of boron in N is greater than 0 and less than 0.1.

[0022] The total of the above atomic ratios d, e, and f is 1.

[0023] The atomic ratios 'a' and 'd' mentioned above satisfy 0.05 ≤ da ≤ 0.2.

[0024] The atomic ratios b and e satisfy 0.05 ≤ be ≤ 0.2. Attached Figure Description

[0025] Figure 1 This is a three-dimensional diagram illustrating one method of using a cutting tool.

[0026] Figure 2 This is a schematic cross-sectional view of the cutting tool in one embodiment of this invention.

[0027] Figure 3 This is a schematic cross-sectional view of the cutting tool in another embodiment of this invention.

[0028] Figure 4 This is a schematic cross-sectional view illustrating the crystal structure of the hard layer involved in this embodiment.

[0029] Figure 5 This is an example of a spectrum obtained during X-ray diffraction analysis of the hard layer involved in this embodiment.

[0030] Figure 6 This is a schematic cross-sectional view of the cutting tool in another embodiment of this invention. Detailed Implementation

[0031] [The problem this disclosure aims to solve]

[0032] In the surface-coated cutting tool described in Patent Document 1, it is expected that the hard coating layer with the above-described structure will improve wear resistance and thus extend the tool's life. In the surface-coated cutting tool described in Patent Document 2, it is expected that the coating with the above-described structure will suppress interlayer delamination and crack propagation, thus extending the tool's life. However, in recent years, the advancement of high-speed and high-efficiency machining has increased the load on cutting tools, leading to a trend of shortened tool life. Therefore, there is a pursuit to further improve the mechanical properties of the coating on cutting tools (e.g., wear resistance, chip resistance, heat resistance, etc.).

[0033] This disclosure was made in view of the above circumstances, with the aim of providing a cutting tool with excellent resistance to chipping.

[0034] [The Effects of This Disclosure]

[0035] Based on the above, cutting tools with excellent resistance to chipping can be provided.

[0036] [Description of embodiments of this disclosure]

[0037] First, embodiments of this disclosure are listed and described.

[0038] [1] The cutting tool disclosed herein includes a substrate and a hard layer disposed on the substrate.

[0039] The aforementioned hard layer comprises a first unit layer and a second unit layer.

[0040] In the aforementioned hard layer, the first unit layer and the second unit layer are alternately stacked one or more times.

[0041] The thickness of the first unit layer is greater than 2 nm and less than 100 nm.

[0042] The thickness of the aforementioned second unit layer is greater than 2 nm and less than 100 nm.

[0043] The first unit layer mentioned above consists of Ti a Al b B c The compound represented by N is composed of...

[0044] The aforementioned second unit layer consists of Ti d Al e B f The compound represented by N is composed of...

[0045] The above Ti a Al b B c The atomic ratio of titanium in N is greater than 0.25 and less than 0.45.

[0046] The above Ti a Al b B c The atomic ratio of aluminum in N is greater than or equal to 0.55 and less than 0.75.

[0047] The above Ti a Al b B c The atomic ratio of boron in nitrogen (N) is greater than 0 and less than 0.1.

[0048] The total of the above atomic ratios a, b, and c is 1.

[0049] The above Ti d Al e Bf The atomic ratio of titanium in nitrogen (d) is greater than 0.35 and less than 0.55.

[0050] The above Ti d Al e B f The atomic ratio of aluminum in nitrogen (N) is greater than 0.45 and less than 0.65.

[0051] The above Ti d Al e B f The atomic ratio f of boron in N is greater than 0 and less than 0.1.

[0052] The total of the above atomic ratios d, e, and f is 1.

[0053] The atomic ratios 'a' and 'd' mentioned above satisfy 0.05 ≤ da ≤ 0.2.

[0054] The atomic ratios b and e satisfy 0.05 ≤ be ≤ 0.2.

[0055] The hard layer in the aforementioned cutting tool, by setting the atomic ratio of boron in both the first and second unit layers within the aforementioned range, results in a cutting tool with excellent resistance to chipping. That is, by possessing the above configuration, the cutting tool exhibits excellent resistance to chipping. Furthermore, by setting the atomic ratio of aluminum in both the first and second unit layers within the aforementioned range, the hard layer results in a cutting tool with excellent heat resistance. Here, "resistance to chipping" refers to resistance to chipping of the cutting tool during machining. "Heat resistance" refers to resistance to wear, deformation, etc., of the cutting tool under high-temperature environments.

[0056] [2] Preferably, the intensity I of the X-ray diffraction peak of the (200) plane in the above-mentioned hard layer is... (200) The intensity I of the X-ray diffraction peak of the (002) plane (002) The ratio of I (200) / I (002) 2 or higher

[0057] The half-width at half-maximum (WHM) of the X-ray diffraction peaks on the (002) plane is preferably 2 degrees or more. This specification allows the cutting tool to further exhibit excellent resistance to chipping. Furthermore, the cutting tool also exhibits excellent heat resistance.

[0058] [3] The hardness H of the hard layer at room temperature is preferably 30 GPa or higher. By specifying this, the cutting tool can have excellent wear resistance in addition to excellent resistance to chipping. Here, "wear resistance" refers to the resistance to wear of the cutting tool during cutting.

[0059] [4] The ratio of the hardness H of the hard layer at room temperature to the Young's modulus E of the hard layer, H / E, is preferably 0.07 or higher. By specifying this, the cutting tool can further possess excellent resistance to chipping.

[0060] [5] The thickness of the hard layer is preferably 1 μm or more and 20 μm or less. By specifying this, the cutting tool can have excellent wear resistance in addition to excellent chip resistance.

[0061] [Details of the embodiments disclosed herein]

[0062] Hereinafter, one embodiment of the present disclosure (hereinafter referred to as "this embodiment") will be described. However, this embodiment is not limited thereto. In this specification, the expression "A to Z" refers to the upper and lower limits of a range (i.e., above A and below Z). When no unit is stated in A, but only in Z, the unit of A is the same as the unit of Z. Furthermore, in this specification, when a compound is represented by a chemical formula in which the composition ratio of the constituent elements is not limited, such as "TiN", the chemical formula includes all composition ratios (element ratios) currently known. In this case, the above chemical formula includes not only stoichiometric composition but also non-stoichiometric composition. For example, in the chemical formula of "TiN", not only is the stoichiometric composition "Ti1N1" included, for example, "Ti1N". 0.8 Such a non-stoichiometric composition. This situation is also the case in the description of compounds other than "TiN".

[0063] Cutting Tools

[0064] A cutting tool comprising a substrate and a hard layer disposed on the substrate, wherein,

[0065] The aforementioned hard layer comprises a first unit layer and a second unit layer.

[0066] In the aforementioned hard layer, the first unit layer and the second unit layer are alternately stacked one or more times.

[0067] The thickness of the first unit layer is greater than 2 nm and less than 100 nm.

[0068] The thickness of the aforementioned second unit layer is greater than 2 nm and less than 100 nm.

[0069] The first unit layer mentioned above consists of Ti a Al b B c The compound represented by N is composed of...

[0070] The aforementioned second unit layer consists of Ti dAl e B f The compound represented by N is composed of...

[0071] The above Ti a Al b B c The atomic ratio of titanium in N is greater than 0.25 and less than 0.45.

[0072] The above Ti a Al b B c The atomic ratio of aluminum in N is greater than or equal to 0.55 and less than 0.75.

[0073] The above Ti a Al b B c The atomic ratio of boron in nitrogen (N) is greater than 0 and less than 0.1.

[0074] The total of the above atomic ratios a, b, and c is 1.

[0075] The above Ti d Al e B f The atomic ratio of titanium in nitrogen (d) is greater than 0.35 and less than 0.55.

[0076] The above Ti d Al e B f The atomic ratio of aluminum in nitrogen (N) is greater than 0.45 and less than 0.65.

[0077] The above Ti d Al e B f The atomic ratio f of boron in N is greater than 0 and less than 0.1.

[0078] The total of the above atomic ratios d, e, and f is 1.

[0079] The atomic ratios 'a' and 'd' mentioned above satisfy 0.05 ≤ da ≤ 0.2.

[0080] The atomic ratios b and e satisfy 0.05 ≤ be ≤ 0.2.

[0081] The cutting tools involved in this embodiment may be, for example, drill bits, end mills, indexable cutting inserts for drill bits, indexable cutting inserts for end mills, indexable cutting inserts for milling, indexable cutting inserts for turning, metalworking saws, tooth cutting tools, reamers, taps, etc.

[0082] Figure 1This is a perspective view illustrating one type of cutting tool. The cutting tool with the above-described shape is, for example, used as an indexable cutting insert. The cutting tool 10 has a rake face 1, a flank face 2, and a cutting edge 3 where the rake face 1 and flank face 2 intersect. That is, the rake face 1 and flank face 2 are surfaces that connect by clamping the cutting edge 3. The cutting edge 3 constitutes the cutting tip of the cutting tool 10. The shape of the cutting tool 10 also reflects the shape of the cutting tool substrate. That is, the substrate has a rake face, a flank face, and a cutting edge connecting the rake face and flank face.

[0083] <Substrate>

[0084] Regarding the substrate used in this embodiment, any substrate known in the art as such 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 other than WC, cemented carbide containing carbonitrides such as Cr, Ti, Ta, Nb, etc. other than WC), cermet (with TiC, TiN, TiCN, etc. as the main components), high-speed steel, ceramics (titanium carbide, silicon carbide, silicon nitride, aluminum nitride, alumina, etc.), cubic boron nitride sintered bodies (cBN sintered bodies), and diamond sintered bodies.

[0085] Among the various substrates mentioned above, cemented carbide (especially WC-based cemented carbide) and cermet (especially TiCN-based cermet) are particularly preferred. This is because these substrates exhibit an excellent balance between hardness and strength at high temperatures, making them superior materials for cutting tools used in the aforementioned applications.

[0086] When using cemented carbide as the substrate, the cemented carbide exhibits the effects of this embodiment even when the microstructure contains free carbon or an abnormal phase called the η phase. It should be noted that the substrate used in this embodiment can be a surface-modified substrate. 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-cured layer can be formed; even with such surface modification, the effects of this embodiment are still observed.

[0087] When the aforementioned cutting tool is an indexable cutting insert (indexable cutting insert for turning, indexable cutting insert for milling, etc.), the base material includes cases with and without a chip breaker. The shape of the edge portion of the tool tip includes any of the following: a sharp edge (the edge where the rake face and flank face intersect), honing (a shape formed by applying an arc to a sharp edge), a negative cutting edge (a shape that is chamfered), or a shape formed by combining honing and a negative cutting edge.

[0088] <Lamination>

[0089] The coating involved in this embodiment is applied to the aforementioned substrate. The "coating" improves various properties of the cutting tool, such as heat resistance, chip resistance, and wear resistance, by covering at least a portion of the substrate (e.g., a portion of the rake face). Preferably, the coating covers the entire surface of the substrate. However, even if a portion of the substrate is not covered by the coating or the composition of the coating is partially different, it does not depart from the scope of this embodiment. The coating comprises a hard layer having a first unit layer and a second unit layer.

[0090] The thickness of the aforementioned coating is preferably 1 μm or more and 20 μm or less, more preferably 1.5 μm or more and 12 μm or less, and even more preferably 2 μm or more and 8 μm or less. Here, the thickness of the coating refers to the sum of the thicknesses of each layer constituting the coating. Examples of "layers constituting the coating" include, for example, the aforementioned hard layer, the substrate layer, the intermediate layer, and the surface layer. The thickness of the coating can be determined, for example, by measuring any ten points in a cross-sectional sample parallel to the normal direction of the substrate surface using a transmission electron microscope (TEM), and taking the average thickness of the ten measured points. The magnification at this time is, for example, 10,000x. Examples of such cross-sectional samples include, for example, samples obtained by slicing the cross-section of the aforementioned cutting tool using an ion slicing apparatus. The same applies to measuring the thicknesses of the aforementioned hard layer, substrate layer, intermediate layer, and surface layer. Examples of such transmission electron microscopes include, for example, the JEM-2100F (trade name) manufactured by Nippon Electron Ltd.

[0091] (hard layer)

[0092] The hard layer 20 involved in this embodiment includes a first unit layer 21 and a second unit layer 22. Figure 2 In the aforementioned hard layer 20, the first unit layer 21 and the second unit layer 22 are alternately stacked in one or more layers. Figure 2 , Figure 3 , Figure 6 The hard layer can begin from either the first unit layer 21 or the second unit layer. As long as the effect of the cutting tool described in this embodiment can be maintained, the hard layer 20 can also be disposed directly above the substrate 11. Figure 2 , Figure 3 It can also be disposed on the substrate 11 via other layers such as the base layer 31. Figure 6 As long as the cutting tool's function is maintained, other layers such as a surface layer 32 can also be provided on the aforementioned hard layer 20. Figure 6 Alternatively, the aforementioned rigid layer 20 may also be disposed on the surface of the aforementioned coating 40.

[0093] Based on one aspect of this embodiment, multiple hard layers can be provided as long as the effect of the cutting tool can be maintained. For example, when the coating includes a first hard layer and a second hard layer, the coating may also include an intermediate layer disposed between the first hard layer and the second hard layer.

[0094] The aforementioned hard layer preferably covers the flank face of the substrate. The aforementioned hard layer preferably covers the rake face of the substrate. More preferably, the aforementioned hard layer covers the entire surface of the substrate. However, even if a portion of the substrate is not covered by the aforementioned hard layer, it does not depart from the scope of this embodiment.

[0095] The thickness of the aforementioned hard layer is preferably 1 μm or more and 20 μm or less, more preferably 1.5 μm or more and 12 μm or less, and even more preferably 2 μm or more and 8 μm or less. This allows the cutting tool to exhibit excellent wear resistance. This thickness can be measured, for example, by observing the cross-section of the aforementioned cutting tool at 10,000x magnification using a transmission electron microscope.

[0096] (X-ray diffraction analysis in hard layers)

[0097] The intensity I of the X-ray diffraction peak of the (200) plane in the aforementioned hard layer (200) The intensity I of the X-ray diffraction peak of the (002) plane (002) The ratio of I (200) / I (002) 2 or higher

[0098] The half-width of the X-ray diffraction peak of the (002) plane is preferably 2 degrees or more. Here, the intensity I of the X-ray diffraction peak of the (200) plane... (200) "This refers to the diffraction intensity (peak height) at the highest peak among the X-ray diffraction peaks originating from the (200) plane." "The intensity I of the X-ray diffraction peaks from the (002) plane..." (002) "The same."

[0099] Specifically, under the conditions described in the embodiments below, X-ray diffraction (XRD) measurements based on the θ / 2θ method are performed on any three points in the aforementioned hard layer to determine the X-ray diffraction intensity of a predetermined crystal plane. The average of the X-ray diffraction intensities at the three points is taken as the X-ray diffraction intensity of the predetermined crystal plane. At this time, the X-ray diffraction intensity of the (200) plane corresponds to the X-ray diffraction intensity near 2θ = 43–44°, and the X-ray diffraction intensity of the (002) plane corresponds to the X-ray diffraction intensity near 2θ = 30–40° (for example, refer to...). Figure 5 ).exist Figure 5In the diagram, the vertical axis represents the diffraction intensity of X-rays, and the horizontal axis represents the value of 2θ. Examples of devices used for the aforementioned X-ray diffraction measurement include "SmartLab" (trade name) manufactured by Rigaku Corporation and "X'pert" (trade name) manufactured by PANalytical.

[0100] The X-ray diffraction intensity of the (200) plane originates from the cubic crystal in the hard layer. The intensity I of the X-ray diffraction peak of the (002) plane. (002) These crystals originate from hexagonal crystals within the hard layer. Therefore, the presence or absence of cubic or hexagonal crystals within the hard layer can be determined based on the presence or absence of these peaks. Furthermore, compared to I... (200) / I (002) A value of 2 or higher refers to a mixed crystal structure in which cubic columnar crystals 23 and hexagonal columnar crystals 24 are formed within the hard layer. Figure 4 In the columnar crystals 23 of the cubic crystal and 24 of the hexagonal crystal, the first unit layer and the second unit layer are alternately stacked. Figure 4 For convenience, the structure of this layer has been omitted.

[0101] The above ratio I (200) / I (002) The upper limit can be, for example, below 10, less than 10, or below 5.

[0102] The upper limit of the half-width of the X-ray diffraction peak of the above (002) plane can be less than 4 degrees or less than 3 degrees.

[0103] (Mechanical properties in the hard layer)

[0104] In this embodiment, the hardness H of the hard layer at room temperature is preferably 30 GPa or more, more preferably 30 GPa or more and 50 GPa or less, and even more preferably 35 GPa or more and 45 GPa or less.

[0105] In this embodiment, the Young's modulus E of the aforementioned hard layer at room temperature is preferably 700 GPa or less, more preferably 400 GPa or more and 700 GPa or less, and even more preferably 400 GPa or more and 550 GPa or less.

[0106] Furthermore, the ratio of the hardness H of the aforementioned hard layer at room temperature to the Young's modulus E of the aforementioned hard layer, H / E, is preferably 0.07 or more, more preferably 0.07 or more and 0.12 or less, and even more preferably 0.08 or more and 0.11 or less.

[0107] The aforementioned hardness H and Young's modulus E can be determined using nanoindentation based on the standard procedures specified in "ISO 14577-1:2015 Metallic materials - Instrumented indentation test for hardness and materials parameters -". In this embodiment, "room temperature" refers to 25°C. From the viewpoint of accurately determining the aforementioned hardness H and Young's modulus E, the indentation depth of the indenter is ensured to be no more than 1 / 10 of the thickness of the hard layer in the indentation direction of the indenter. The indentation load of the indenter is set to 1g. As long as it can be ensured that the cross-sectional area of ​​the hard layer is ten times the area of ​​the indenter, the aforementioned cross-sectional sample can be used. Alternatively, a sample with a cross-section inclined relative to the normal direction of the substrate surface can be used to ensure that the cross-sectional area of ​​the hard layer has sufficient area relative to the indenter. The above measurements are performed on at least ten cross-sectional samples, and the average value of the hardness and Young's modulus determined from each sample is taken as the hardness H and Young's modulus E of the hard layer. It should be noted that data that appears to be outliers at first glance are removed. For example, the ENT-1100a manufactured by Elionix can be cited as an example of an apparatus for performing the aforementioned nanoindentation method.

[0108] (First unit layer)

[0109] The thickness of the first unit layer is 2 nm or more and 100 nm or less, preferably 2 nm or more and 50 nm or less, and more preferably 2 nm or more and 10 nm or less. The thickness of the first unit layer and the thickness of the second unit layer, as described below, are determined using electron energy loss spectroscopy (EELS). Specifically, firstly, in a scanning transmission electron microscope (STEM) image of the cross-sectional sample, the intensity distribution corresponding to Al is measured along a direction parallel to the stacking direction of the hard layer. Then, the intensity distribution is represented by a line graph with the X-axis (horizontal axis) representing the distance from the measurement starting point on the hard layer and the Y-axis (vertical axis) representing the intensity (due to the brightness of atoms). Next, in the obtained graph, the distance between the point representing the maximum value of the line graph corresponding to Al and the point representing the next maximum value is calculated. The calculated distance refers to the total thickness of the first unit layer and the second unit layer. Calculate the total thicknesses obtained in this way for at least four locations, and find their average value. Divide the average value by 2 to obtain the thicknesses of the first unit layer and the second unit layer.

[0110] The first unit layer mentioned above consists of Ti a Al b B c The compound represented by N is composed of... Here, "made of Ti..." aAl b B c "The compound composition shown in N" refers to compounds consisting solely of Ti. a Al b B c The composition of the compound shown by N, and the composition of Ti a Al b B c The concept of N represents the composition of the compound and unavoidable impurities. Examples of unavoidable impurities include, for instance, carbon (C) and oxygen (O). The composition of the first unit layer can be determined by performing elemental analysis on the entire first unit layer using energy-dispersive X-ray spectroscopy (TEM-EDX) on the aforementioned cross-sectional sample. The magnification at this time is, for example, 20,000x.

[0111] The above Ti a Al b B c The atomic ratio 'a' of titanium in N is 0.25 or more and less than 0.45, preferably 0.25 or more and less than 0.40, and more preferably 0.25 or more and less than 0.35. By taking the above-mentioned atomic ratio 'a' within the above-mentioned range, a first unit layer with moderate hardness is obtained.

[0112] The above Ti a Al b B c The atomic ratio b of aluminum in N is 0.55 or more and less than 0.75, preferably 0.60 or more and less than 0.75, and more preferably 0.65 or more and less than 0.75. By taking the above-mentioned atomic ratio b within the above-mentioned range, a first unit layer with excellent heat resistance is obtained.

[0113] The above Ti a Al b B c The atomic ratio c of boron in N is greater than 0 and less than 0.1, preferably more than 0.01 and less than 0.09, and more preferably more than 0.02 and less than 0.08. By taking the above-mentioned atomic ratio c within the above range, a first unit layer with moderate hardness is obtained. It should be noted that the total of the above-mentioned atomic ratios a, b, and c is 1.

[0114] (Second unit layer)

[0115] The thickness of the second unit layer is 2 nm or more and 100 nm or less, preferably 2 nm or more and 50 nm or less, and more preferably 2 nm or more and 10 nm or less.

[0116] The aforementioned second unit layer consists of Ti d Al e B fThe compound represented by N is composed of... Here, "made of Ti..." d Al e B f "The compound composition shown in N" refers to compounds consisting solely of Ti. d Al e B f The composition of the compound shown by N, and the composition of Ti d Al e B f The concept of N represents the composition of the compound and unavoidable impurities. Examples of unavoidable impurities include, for instance, carbon (C) and oxygen (O). The composition of the second unit layer can be determined by performing elemental analysis on the entire second unit layer using energy-dispersive X-ray spectroscopy (TEM-EDX) on the aforementioned cross-sectional sample. The magnification at this time is, for example, 20,000x.

[0117] The above Ti d Al e B f The atomic ratio d of titanium in N is 0.35 or more and less than 0.55, preferably 0.35 or more and less than 0.50, and more preferably 0.35 or more and less than 0.45. By taking the above-mentioned atomic ratio d within the above-mentioned range, a first unit layer with moderate hardness is obtained.

[0118] The above Ti d Al e B f The atomic ratio e of aluminum in N is 0.45 or more and less than 0.65, preferably 0.50 or more and less than 0.65, and more preferably 0.55 or more and less than 0.65. By taking the above-mentioned atomic ratio e within the above range, a first unit layer with moderate hardness is obtained.

[0119] The above Ti d Al e B f The atomic ratio f of boron in N is greater than 0 and less than 0.1, preferably more than 0.01 and less than 0.09, and more preferably more than 0.02 and less than 0.08. By taking the above-mentioned atomic ratio f within the above range, a first unit layer with moderate hardness is obtained. It should be noted that the total of the above-mentioned atomic ratios d, e, and f is 1.

[0120] In this embodiment, the atomic ratios a and d satisfy 0.05 ≤ da ≤ 0.2, and preferably 0.1 ≤ da ≤ 0.2. By making da take the above range, a cutting tool with excellent resistance to chipping is obtained.

[0121] In this embodiment, the atomic ratios b and e satisfy 0.05 ≤ be ≤ 0.2, and preferably 0.1 ≤ be ≤ 0.2. By taking be within the above range, a cutting tool with excellent resistance to chipping is obtained.

[0122] (Other layers)

[0123] Provided that the effect of this embodiment is not compromised, the coating may also include other layers. Examples of such other layers include a base layer disposed between the substrate and the rigid layer, and a surface layer disposed on the rigid layer. Additionally, an intermediate layer disposed between the first and second rigid layers may be included when the coating comprises a first rigid layer and a second rigid layer.

[0124] The aforementioned base layer may, for example, be a layer composed of a compound represented by AlCrN. The aforementioned surface layer may, for example, be a layer composed of a compound represented by TiN. The aforementioned intermediate layer may, for example, be a layer composed of a compound represented by TiAlN. The composition of the other layers can be determined by performing elemental analysis of the entire other layers using energy-dispersive X-ray spectroscopy (TEM-EDX) on the aforementioned cross-sectional sample. The magnification at this time is, for example, 20,000x.

[0125] There are no particular limitations on the thickness of the other layers mentioned above, without impairing the effects of this embodiment; for example, thicknesses of 0.1 μm or more and 2 μm or less can be listed. This thickness can be measured, for example, by observing the cross-section of the cutting tool described above at 10,000x magnification using a transmission electron microscope.

[0126] Manufacturing Methods of Cutting Tools

[0127] The method for manufacturing the cutting tool involved in this embodiment includes:

[0128] The process of preparing the above-mentioned substrate (hereinafter, sometimes referred to as "the first process");

[0129] The process of forming the hard layer by alternately stacking one or more first unit layers and second unit layers on the above-mentioned substrate using physical vapor deposition (hereinafter, sometimes referred to as the "second process").

[0130] Physical vapor deposition refers to a deposition method that uses physical action to vaporize a raw material (also called an "evaporation source" or "target") and then deposits the vaporized material onto a substrate or similar object. Examples of physical vapor deposition methods include sputtering and arc ion plating. In particular, arc ion plating is preferably used as the physical vapor deposition method in this embodiment.

[0131] In the arc ion plating method, after placing a substrate in the apparatus and setting a target as the cathode, a high current is applied to the target to generate an arc discharge. As a result, the atoms constituting the target evaporate and ionize, depositing onto the substrate under a negative bias voltage to form a coating.

[0132] <First Process: Preparation of Substrate>

[0133] In the first step, a substrate is prepared. For example, a cemented carbide substrate or a cubic boron nitride sintered body is prepared as the substrate. Commercially available substrates can be used for both the cemented carbide substrate and the cubic boron nitride sintered body, or they can be manufactured using conventional powder metallurgy methods. For example, when manufacturing cemented carbide using conventional powder metallurgy methods, firstly, WC powder and Co powder are mixed using a ball mill or the like to obtain a mixed powder. After drying the mixed powder, it is shaped into a predetermined shape to obtain a shaped body. Further, by sintering the shaped body, a WC-Co based cemented carbide (sintered body) is obtained. Next, a predetermined tool tip machining process, such as honing, is applied to the sintered body, thereby enabling the manufacture of a substrate composed of WC-Co based cemented carbide. In the first step, any substrate other than those described above can be prepared as such, as long as it is a known substrate.

[0134] <Second process: The process of forming a hard layer>

[0135] In the second step, a physical vapor deposition method is used to alternately stack one or more first unit layers and second unit layers on the aforementioned substrate to form the aforementioned hard layer. Various methods are used depending on the composition of the hard layer to be formed. Examples include methods using alloy targets with varying particle sizes of titanium (Ti), aluminum (Al), and boron (B); methods using multiple targets with different compositions; methods applying a pulsed voltage during film formation; methods changing the gas flow rate during film formation; and methods adjusting the rotational speed of the substrate holder in the film formation apparatus.

[0136] For example, the second step can be performed as follows. First, a blade of any shape is installed as a substrate in the chamber of the film-forming apparatus. For example, the substrate is installed on the outer surface of a substrate holder rotatably mounted on a central rotating table within the chamber of the film-forming apparatus. Next, the evaporation source for forming the first unit layer and the evaporation source for forming the second unit layer are arranged opposite each other, sandwiching the substrate holder. A bias power supply is installed on the substrate holder. An arc power supply is installed on the evaporation source for forming the first unit layer and the evaporation source for forming the second unit layer, respectively. With the substrate rotated in the center of the chamber, nitrogen or the like is introduced as a reaction gas. Further, the substrate is maintained at a temperature of 400–800°C, and the reaction gas pressure is maintained at 1–10 Pa (the partial pressure of nitrogen is 5–10 Pa). While gradually varying the voltage of the bias power supply within the range of 30–200 V (DC power supply), an arc current of 80–200 A is alternately supplied to the evaporation source for forming the first unit layer and the evaporation source for forming the second unit layer. Therefore, metal ions are generated from the evaporation sources for forming the first unit layer and the second unit layer. When the substrate is placed opposite the evaporation source for forming the first unit layer, a first unit layer is formed; when the substrate is placed opposite the evaporation source for forming the second unit layer, a second unit layer is formed. Furthermore, film formation occurs while varying the voltage of the bias power supply as described above, thereby achieving both high hardness of the hard layer and cutting edge quality. After a predetermined time, the supply of the arc current is stopped, and a hard layer (the first unit layer and the second unit layer) is formed on the surface of the substrate. At this time, the thickness of the first unit layer and the second unit layer is adjusted by adjusting the rotation speed of the substrate. Additionally, the film formation time is adjusted to bring the thickness of the hard layer within a predetermined range. In the second step described above, a hard layer may also be formed on the surface of the substrate other than the cutting-related portion, in addition to forming a hard layer on the surface of the substrate in relation to the cutting process (e.g., the rake face near the cutting edge).

[0137] It has long been known that layers composed of compounds such as TiAlN (TiAlN layers) are predominantly cubic and exhibit excellent hardness. However, it is also known that adding boron as a raw material during the formation of the TiAlN layer easily leads to the formation of hexagonal crystals and a decrease in hardness. Therefore, the idea of ​​using boron as a raw material in the formation of TiAlN layers, based on the use of titanium and aluminum, has generally not been to use boron as a raw material. The inventors, however, did not adhere to this conventional wisdom and attempted to form a hard layer by adding a trace amount of boron to titanium and aluminum, and further constructing a multilayer structure consisting of a first unit layer and a second unit layer. They first discovered a cutting tool with excellent heat resistance and excellent chip resistance, contrary to expectations.

[0138] In one aspect of this embodiment, preferably, the substrate is maintained at a temperature of 500–600°C, the reactant gas pressure is maintained at 5–10 Pa (the partial pressure of nitrogen is 5–8 Pa), and while the voltage of the bias power supply is gradually varied within the range of 30–200 V (DC power supply), an arc current of 80–120 A is alternately supplied to the evaporation source for forming the first unit layer and the evaporation source for forming the second unit layer. In this way, a mixed-crystal structure of cubic and hexagonal crystals can be formed in the hard layer. By setting the structure as described above, the coarsening of the columnar crystals of both the cubic and hexagonal crystals is suppressed, thereby improving the toughness and heat resistance of the hard layer.

[0139] (Raw material of the first unit layer)

[0140] In the second step described above, the raw materials for the first unit layer include titanium, aluminum, and boron, such as titanium boride, metallic aluminum, and titanium aluminum boride. The composition of the raw materials for the first unit layer can be appropriately adjusted according to the desired composition of the first unit layer. The raw materials for the first unit layer can be in powder or plate form.

[0141] (Raw material of the second unit layer)

[0142] In the second step described above, the raw materials for the second unit layer include titanium, aluminum, and boron, such as metallic titanium, aluminum boride, and titanium aluminum boride. The composition of the raw materials for the second unit layer can be appropriately adjusted according to the desired composition of the second unit layer. Preferably, the composition of the raw materials for the second unit layer differs from that of the raw materials for the first unit layer. The raw materials for the second unit layer can be in powder or plate form.

[0143] In this embodiment, the reaction gas described above is appropriately set according to the composition of the hard layer. Examples of the reaction gas include a mixture of nitrogen and argon, and nitrogen gas itself.

[0144] <Other Processes>

[0145] In the manufacturing method described in this embodiment, in addition to the steps described above, steps such as ion bombardment treatment of the surface of the substrate, forming a base layer between the substrate and the hard layer, forming a surface layer on the hard layer, forming an intermediate layer between the first hard layer and the second hard layer, and surface treatment may be performed appropriately between the first step and the second step.

[0146] In cases where other layers such as the base layer, intermediate layer, and surface layer are formed, these other layers can be formed using existing methods.

[0147] Example

[0148] The present invention will be described in detail below with reference to specific embodiments, but the present invention is not limited thereto.

[0149] Making Cutting Tools

[0150] <Preparation of Substrate>

[0151] First, as the substrate to which the coating is formed, an indexable cutting insert P for milling (JIS standard P30 equivalent cemented carbide, SEMT13T3AGSN) and an indexable cutting insert K for milling (JIS standard K30 equivalent cemented carbide, SEMT13T3AGSN) are prepared (first step).

[0152] <Ion bombardment treatment>

[0153] Prior to the coating process described below, the surface of the substrate underwent ion bombardment treatment via the following steps. First, the substrate was placed in an arc ion plating apparatus. Next, ion bombardment treatment was performed under the following conditions.

[0154] Gas composition: Ar (100%)

[0155] Atmospheric pressure: 0.5 Pa

[0156] Bias voltage: 600V (DC power supply)

[0157] Processing time: 60 minutes

[0158] <Lamination process>

[0159] A coating was produced by forming a hard layer (multilayer structure or single layer) as shown in Tables 2-1 to 2-3 on the surface of the aforementioned substrate that had undergone ion bombardment treatment. The method for producing the hard layer will be described below.

[0160] (Creation of the hard layer)

[0161] In samples 1-22, 102-104, and 106-109, nitrogen gas was introduced as a reaction gas while the substrate (indexable milling insert P and indexable milling insert K) was rotated in the center of the chamber. Furthermore, the substrate was maintained at a temperature of 550°C, and the reaction gas pressure was maintained at 8 Pa (partial pressure of nitrogen: 8 Pa). While gradually varying the voltage of the bias power supply within the range of 35-180 V, an arc current of 90 A was alternately supplied to the evaporation sources for forming the first and second unit layers, respectively. As a result, metal ions were generated from the evaporation sources for forming the first and second unit layers, respectively. After a predetermined time, the supply of the arc current was stopped, and a hard layer (second step) with the composition shown in Tables 2-1 to 2-3 was formed on the surface of the substrate. Here, the evaporation sources for forming the first and second unit layers used the raw material compositions shown in Tables 1-1 and 1-2, respectively. At this point, a hard layer was fabricated by alternately stacking the first unit layer and the second unit layer, each with the composition shown in Tables 2-1 to 2-3, while adjusting the rotation speed of the substrate to achieve the thicknesses shown in Tables 2-1 to 2-3. The composition of the hard layer in Tables 2-1 to 2-3 was determined, as described above, by performing elemental analysis of the entire hard layer on a cross-sectional sample using energy-dispersive X-ray spectroscopy (TEM-EDX) attached to the TEM. The magnification at this time was 20,000x.

[0162] For samples 101 and 105, the films were formed using only the evaporation source for forming the first unit layer (Tables 1-2 and 2-3). Therefore, the hard layer in samples 101 and 105 is not a multilayer structure, but a single layer.

[0163] Through the above procedures, cutting tools for samples 1-22 and samples 101-109 were produced.

[0164] Table 1-1

[0165]

[0166] Table 1-2

[0167]

[0168]

[0169]

[0170]

[0171] Evaluation of Cutting Tool Characteristics

[0172] Using the cutting tools of specimens 1-22 and specimens 101-109 prepared as described above, the characteristics of the cutting tools were evaluated as follows. It should be noted that the cutting tools of specimens 1-22 correspond to the examples, and the cutting tools of specimens 101-109 correspond to the comparative examples.

[0173] <Determination of coating thickness (thickness of hard layer)>

[0174] Ten arbitrary points in a cross-sectional sample parallel to the normal direction of the substrate surface were measured using a transmission electron microscope (TEM) (manufactured by Nippon Electron Ltd., trade name: JEM-2100F). The thickness of the coating (i.e., the thickness of the hard layer) was calculated by averaging the thicknesses of the ten measured points. The results are shown in Tables 2-1 and 2-2.

[0175] Furthermore, in samples 1-22, 102-104, and 106-109, when the coating was observed by STEM, it was found that the hard layer was formed by alternating layers of the first unit layer and the second unit layer.

[0176] <Determination of the thickness of the first unit layer and the second unit layer>

[0177] The thicknesses of the first and second unit layers were determined using EELS analysis. Specifically, in the STEM images obtained through the above measurements, the intensity distribution corresponding to Al was measured along a direction parallel to the stacking direction of the aforementioned hard layers. This intensity distribution was represented by a line graph with the X-axis (horizontal axis) representing the distance from the measurement starting point on the aforementioned hard layer and the Y-axis (vertical axis) representing the intensity (due to the brightness of atoms). In the obtained graph, the distance between the point representing the maximum value of the line graph corresponding to Al and the point representing the next maximum value was calculated. The calculated distance refers to the total thickness of the first and second unit layers. The total thicknesses thus calculated were calculated at at least four locations, and their average value was obtained. The value obtained by dividing the average value by 2 is the thickness of the first and second unit layers. The results are shown in Tables 2-1 and 2-2.

[0178] <X-ray Diffraction Analysis of Hard Layers>

[0179] The hard layer was analyzed using X-ray diffraction (XDR) analysis, and the X-ray diffraction intensities I of the (200) and (002) planes were determined. (200) and I (002) The conditions for X-ray diffraction analysis are shown below. The calculated I... (200) / I (002) and I (002)The peak half-width is shown in Table 3-1 and Table 3-2.

[0180] Conditions for X-ray diffraction analysis

[0181] Scan axis: 2θ-θ

[0182] X-ray source: Cu-Kα rays

[0183] Detector: 0-dimensional detector (scintillation counter)

[0184] Tube voltage: 45kV

[0185] Tube current: 40mA

[0186] Incident optical systems: the use of mirrors

[0187] Receiving optical system: Utilization of an analyzer crystal (PW3098 / 27)

[0188] Stride length: 0.03°

[0189] Total time: 2 seconds

[0190] Scan range (2θ): 20°~80°

[0191] Furthermore, based on the results of the X-ray diffraction analysis described above, the presence or absence of cubic and hexagonal crystals in the hard layer was determined. The results are shown in Tables 3-1 and 3-2.

[0192] <Analysis of the mechanical properties of the hard layer (analysis of hardness and Young's modulus)>

[0193] The hardness (H) and Young's modulus (E) of the hard layer in each cutting tool were determined using nanoindentation based on the standard procedure specified in "ISO 14577-1:2015 Metallic materials - Instrumented indentation test for hardness and materials parameters -". The indentation depth was set to 100 nm, the indentation load to 1 g, and the measurement temperature to room temperature (25°C). Furthermore, mirror-finished cross-sectional samples were used to ensure that the cross-sectional area of ​​the hard layer was ten times the area of ​​the indenter. The measuring apparatus used was the ENT-1100a (trade name) manufactured by ELIONIX Corporation. The above measurements were performed on ten cross-sectional samples, and the average hardness and Young's modulus obtained from each sample were taken as the hardness (H) and Young's modulus (E) of the hard layer. It should be noted that data that initially appeared to be outliers were removed. The ratio of hardness (H) to Young's modulus (E), H / E, was also calculated. The results are shown in Tables 3-1 and 3-2.

[0194] Table 3-1

[0195]

[0196] Table 3-2

[0197]

[0198] Cutting Test

[0199] <Cutting Evaluation (1)>

[0200] Cutting was performed using the obtained cutting tool (indexable insert P for milling) under the following cutting conditions (cutting distance: 900 mm). The presence or absence of breakage at the tool tip was then observed using an optical microscope. Ten identical cutting tests were performed, and the breakage rate (%) was calculated. It is possible to repeatedly apply impact-based loads to the tool tip during cutting under the following conditions. Therefore, the cutting tool with the lower breakage rate described above can be evaluated as having excellent resistance to breakage. The results are shown in Tables 4-1 and 4-2.

[0201] (Cutting conditions)

[0202] Workpiece to be cut: S50C (with Φ8 holes spaced 18mm apart from each other)

[0203] Cutting speed: 160 m / min.

[0204] Feed rate: 0.65mm / t

[0205] Cut (axial): 2.5mm

[0206] Cut (radial): 100% of tool diameter

[0207] Dry method.

[0208] Cutting Test

[0209] <Cutting Evaluation (2)>

[0210] Using the obtained cutting tool (indexable insert K for milling), machining was performed under the cutting conditions shown below, and the cutting distance until the width of the flank defect near the cut boundary of the tool tip reached 0.5 mm was measured. The results are shown in Tables 4-1 and 4-2. Tables 4-1 and 4-2 show that the cutting tool with a longer cutting distance has better defect resistance.

[0211] (Cutting conditions)

[0212] Workpiece to be machined: Chromium-nickel-iron alloy 718 (shape: square bar)

[0213] Cutting speed: 30 m / min.

[0214] Feed rate: 0.35mm / t

[0215] Cut (axial): 2mm

[0216] Cut (radial): 70% of tool diameter

[0217] wet

[0218] Table 4-1

[0219]

[0220] Table 4-2

[0221]

[0222] <Results>

[0223] According to the results of the cutting evaluation (1), the breakage rate of the cutting tools of specimens 1 to 22 was less than 80%, which is a good result. On the other hand, the breakage rate of the cutting tools of specimens 101 to 109 was more than 90%. Based on the above results, it can be seen that the cutting tools of specimens 1 to 22 involved in the embodiments have excellent resistance to breakage (Table 4-1 and Table 4-2).

[0224] According to the results of the cutting evaluation (2), the cutting distance of the cutting tools for samples 1 to 22 was 1500 mm or more, which yielded good results. On the other hand, the cutting distance of the cutting tools for samples 101 to 109 was 800 mm or less. Based on the above results, it can be seen that the cutting tools for samples 1 to 22 involved in the embodiments have excellent resistance to chipping (Tables 4-1 and 4-2).

[0225] As described above, the embodiments and examples of the present invention have been described. However, it is also originally intended that the above embodiments and examples be appropriately combined.

[0226] 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.

[0227] Explanation of reference numerals in the attached figures

[0228] 1: Front face;

[0229] 2: Back face;

[0230] 3: The edge of the blade;

[0231] 10: Cutting tools;

[0232] 11: Substrate;

[0233] 20: Hard layer;

[0234] 21: First unit layer;

[0235] 22: Second unit layer;

[0236] 23: Columnar crystals of cubic crystals;

[0237] 24: Columnar crystals of hexagonal crystals;

[0238] 31: Basal layer;

[0239] 32: Surface layer;

[0240] 40: Lamination.

Claims

1. A cutting tool, the cutting tool comprising a substrate and a hard layer disposed on the substrate, wherein, The hard layer comprises a first unit layer and a second unit layer. In the hard layer, the first unit layer and the second unit layer are alternately stacked one or more times. The thickness of the first unit layer is greater than 2 nm and less than 100 nm. The thickness of the second unit layer is greater than 2 nm and less than 100 nm. The first unit layer consists of Ti a Al b B c The compound represented by N is composed of... The second unit layer consists of Ti d Al e B f The compound represented by N is composed of... The Ti a Al b B c The atomic ratio of titanium in N is greater than 0.25 and less than 0.

45. The Ti a Al b B c The atomic ratio of aluminum in N is greater than or equal to 0.55 and less than 0.

75. The Ti a Al b B c The atomic ratio of boron in nitrogen (N) is greater than 0 and less than 0.

1. The total of the atomic ratios a, b, and c is 1. The Ti d Al e B f The atomic ratio of titanium in nitrogen (d) is greater than 0.35 and less than 0.

55. The Ti d Al e B f The atomic ratio of aluminum in nitrogen (N) is greater than 0.45 and less than 0.

65. The Ti d Al e B f The atomic ratio f of boron in N is greater than 0 and less than 0.

1. The total of the atomic ratios d, e, and f is 1. The atomic ratios a and d satisfy 0.05 ≤ da ≤ 0.

2. The atomic ratios b and e satisfy 0.05 ≤ be ≤ 0.

2. The intensity I of the X-ray diffraction peak of the (200) plane in the hard layer （200） The intensity I of the X-ray diffraction peak of the (002) plane （002） The ratio of I （200） / I （002） 2 or higher The half-width of the X-ray diffraction peak of the (002) plane is greater than 2 degrees. When X-ray diffraction measurements based on the θ / 2θ method were performed at any three points in the hard layer, The X-ray diffraction intensity of the (200) plane corresponds to the X-ray diffraction intensity near 2θ = 43~44°. The X-ray diffraction intensity of the (002) plane corresponds to the X-ray diffraction intensity near 2θ = 30~40°. The X-ray diffraction intensity of the (200) plane originates from the cubic crystals in the hard layer. The intensity I of the X-ray diffraction peak of the (002) plane （002） Crystals originating from the hexagonal crystals in the hard layer. The ratio I （200） / I （002） A value of 2 or higher refers to the formation of a mixed crystal of cubic columnar crystals and hexagonal columnar crystals in the hard layer.

2. The cutting tool according to claim 1, wherein, The ratio I （200） / I （002） The upper limit is 10 or less, and the half-width of the X-ray diffraction peak of the (002) plane is 4 degrees or less.

3. The cutting tool according to claim 1 or 2, wherein, The hardness H of the hard layer at room temperature is above 30 GPa.

4. The cutting tool according to claim 3, wherein, The hardness H of the hard layer at room temperature is above 30 GPa and below 50 GPa.

5. The cutting tool according to claim 1 or 2, wherein, The Young's modulus E of the hard layer at room temperature is above 400 GPa and below 700 GPa.

6. The cutting tool according to claim 3, wherein, The ratio of the hardness H of the hard layer to the Young's modulus E of the hard layer at room temperature, H / E, is 0.07 or higher.

7. The cutting tool according to claim 6, wherein, The ratio of the hardness H of the hard layer to the Young's modulus E of the hard layer at room temperature, H / E, is greater than 0.07 and less than 0.

12.

8. The cutting tool according to claim 1 or 2, wherein, The Ti a Al b B c The atomic ratio of titanium in N is greater than 0.25 and less than 0.

40.

9. The cutting tool according to claim 1 or 2, wherein, The Ti a Al b B c The atomic ratio of aluminum in N is greater than 0.60 and less than 0.

75.

10. The cutting tool according to claim 1 or 2, wherein, The Ti a Al b B c The atomic ratio of boron in nitrogen (N) is greater than 0.01 and less than 0.

09.

11. The cutting tool according to claim 1 or 2, wherein, The Ti d Al e B f The atomic ratio of titanium in N is greater than 0.35 and less than 0.

50.

12. The cutting tool according to claim 1 or 2, wherein, The Ti d Al e B f The atomic ratio of aluminum in nitrogen (N) is greater than 0.50 and less than 0.

65.

13. The cutting tool according to claim 1 or 2, wherein, The Ti d Al e B f The atomic ratio f of boron in N is greater than 0.01 and less than 0.

09.

14. The cutting tool according to claim 1 or 2, wherein, The thickness of the hard layer is more than 1 μm and less than 20 μm.

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