Coated cutting tool and cutting tool
By forming a multi-layer coating structure and an intermediate layer on a WC-based cemented carbide substrate, the problem of insufficient adhesion between the coating and the substrate is solved, the wear resistance and heat resistance of the coated cutting tool are improved, and the adhesion is enhanced.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- KYOCERA CORP
- Filing Date
- 2022-07-07
- Publication Date
- 2026-07-21
AI Technical Summary
The existing coating has insufficient adhesion to the substrate, leaving room for further improvement in the wear resistance and heat resistance of coated cutting tools.
A WC-based cemented carbide matrix with WC particles as the hard phase and Co as the binder phase is used, and a multi-layer coating structure composed of elements such as Al, Cr, Si, and N is formed on it. The bonding between the matrix and the coating is improved through an intermediate layer. Specific methods include physical vapor deposition and argon bombardment treatment.
It improves the wear resistance, heat resistance and adhesion of coated cutting tools, and extends their service life.
Smart Images
Figure CN117561133B_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to coated cutting tools and cutting tools. Background Technology
[0002] As cutting tools used in cutting processes such as turning or milling, coated tools are known to have useful coatings applied to the surface of substrates such as cemented carbide, cermet, and ceramic, thereby improving their wear resistance and other properties.
[0003] Prior art literature
[0004] Patent documents
[0005] Patent Document 1: International Publication No. 2019 / 146710
[0006] Patent Document 2: Japanese Patent Application Publication No. 2017-193004 Summary of the Invention
[0007] One aspect of the coated cutting tool disclosed herein comprises a substrate of a WC-based cemented carbide, wherein WC particles are the hard phase component and Co is the binder phase component, and a first coating disposed on the substrate. The first coating is composed of at least one element selected from the group consisting of Al, Cr, Si, Group IV elements, Group V elements, and Group VI elements, and at least one element selected from the group consisting of C and N. In the interface region between the substrate and the first coating in a cross section perpendicular to the surface of the substrate, the maximum value (atm%) of Ti obtained by elemental analysis in the direction from the first coating to the WC particles is defined as the Ti(WC) value, and the maximum value (atm%) of Ti obtained by elemental analysis in the direction from the first coating to the binder phase is defined as the Ti(C) value. o When the ratio of Ti(WC) value to Ti(Co) value (Ti(Co) value / Ti(WC) value) is set as the Ti(Co / WC) ratio, the Ti(Co / WC) ratio is 0.8 or less. Attached Figure Description
[0008] Figure 1 This is a perspective view showing an example of a coated cutting tool according to an embodiment.
[0009] Figure 2 This is a side sectional view showing an example of a coated cutting tool according to an embodiment.
[0010] Figure 3 This is a cross-sectional view showing an example of the coating in an embodiment.
[0011] Figure 4 yes Figure 3 An enlarged schematic diagram of section H is shown.
[0012] Figure 5 This is a schematic enlarged view of the interface area between the substrate and the first coating.
[0013] Figure 6 This is a front view showing an example of a cutting tool used in an embodiment.
[0014] Figure 7 It is a table summarizing the manufacturing conditions of the intermediate layer of samples No.1 to No.20.
[0015] Figure 8 This table summarizes the average composition of the first coating, the presence or absence of Ti in the intermediate layer, the Ti (Co / WC) ratio, and the average thickness of the Ti-containing layer on the WC particles for samples No.1 to No.20.
[0016] Figure 9 It is a table summarizing the results of oxidation tests, abrasion tests, and peel tests on samples No.1 to No.20.
[0017] Figure 10 This is a scanning transmission electron microscope image of the coated cutting tool in the embodiment.
[0018] Figure 11 This is a WC mapping image of the coated cutting tool in the embodiment.
[0019] Figure 12 This is a Co-mapping image of the coated cutting tool in the embodiment.
[0020] Figure 13 This is a Ti mapping image of the coated cutting tool in the embodiment.
[0021] Figure 14 This is a graph showing the extraction range on WC and the extraction range on Co.
[0022] Figure 15 This is a chart showing the results of Ti content determination within the extraction range on WC and the extraction range on Co. Detailed Implementation
[0023] Hereinafter, with reference to the accompanying drawings, a detailed description will be provided of the embodiments for implementing coated cutting tools and cutting tools (hereinafter referred to as "Embodiments"). It should be noted that the coated cutting tools and cutting tools of this disclosure are not limited to these embodiments. Furthermore, the various embodiments can be appropriately combined within the scope where the processing content does not contradict each other. In addition, in the following embodiments, the same reference numerals are used to label the same parts, and repeated descriptions are omitted.
[0024] Furthermore, in the embodiments shown below, expressions such as "constant," "orthogonal," "perpendicular," or "parallel" are sometimes used, but these expressions do not need to be "constant," "orthogonal," "perpendicular," or "parallel" in the strict sense. That is, the above expressions allow for deviations in, for example, manufacturing precision, setting precision, etc.
[0025] In the aforementioned prior art, there is room for further improvement in enhancing the adhesion between the coating and the substrate.
[0026] Coated Cutting Tools
[0027] Figure 1 This is a perspective view illustrating an example of a coated cutting tool according to an embodiment. Additionally, Figure 2 This is a side sectional view showing an example of the coated cutting tool 1 according to the embodiment. For example... Figure 1 As shown, the coated cutting tool 1 of the embodiment has a blade body 2.
[0028] (Blade Body 2)
[0029] The blade body 2, for example, has an upper surface and a lower surface (with) Figure 1 The shape of the surfaces intersecting the Z-axis shown is a parallelogram-hexahedron shape.
[0030] One corner of the blade body 2 functions as a cutting edge. The cutting edge has a first face (e.g., an upper surface) and a second face (e.g., a side face) connected to the first face. In an embodiment, the first face functions as a "rake face" to scrape away chips generated by cutting, and the second face functions as a "flank face". The cutting edge is located at least a portion of the edge where the first face and the second face intersect, and the coated tool 1 cuts the workpiece by bringing the cutting edge into contact with the workpiece.
[0031] The through hole 5 of the upper and lower through-body blade 2 is located in the center of the blade body 2. A screw 75 (described later) for mounting the coated tool 1 to the tool holder 70 is inserted into the through hole 5. Figure 6 ).
[0032] like Figure 2 As shown, the blade body 2 has a substrate 10 and a coating 20.
[0033] (Matrix 10)
[0034] The matrix 10 is formed, for example, of a cemented carbide. The cemented carbide contains W (tungsten), specifically WC (tungsten carbide). Alternatively, the cemented carbide may also contain Ni (nickel) or Co (cobalt). Specifically, the matrix 10 is composed of a WC-based cemented carbide with WC particles as the hard phase component and Co as the binder phase component.
[0035] (Coating 20)
[0036] The coating 20 is applied to the substrate 10 for purposes such as improving its wear resistance and heat resistance. Figure 2 In this example, coating 20 completely covers the substrate 10. Coating 20 only needs to be located on at least the substrate 10. When coating 20 is located on the first surface (here, the upper surface) of the substrate 10, the first surface exhibits high wear resistance and heat resistance. When coating 20 is located on the second surface (here, the side surface) of the substrate 10, the second surface exhibits high wear resistance and heat resistance.
[0037] Here, refer to Figure 3 and Figure 4 The specific structure of coating 20 will be explained. Figure 3 This is a cross-sectional view showing an example of coating 20 in an embodiment. Additionally, Figure 4 yes Figure 3 An enlarged schematic diagram of section H is shown.
[0038] like Figure 3 As shown, coating 20 has a first coating 23 located above intermediate layer 22 and a second coating 24 located above first coating 23.
[0039] The first coating 2 is composed of at least one element selected from the group consisting of Al, Cr, Si, Group 4 elements, Group 5 elements and Group 6 elements, and at least one element selected from the group consisting of C and N.
[0040] Specifically, the first coating 23 may also contain Al, Cr, Si, and N. That is, the first coating 23 may also be an AlCrSiN layer containing AlCrSiN nitrides as Al, Cr, and Si. It should be noted that the expression "AlCrSiN" means that Al, Cr, Si, and N exist in any proportion, and does not necessarily mean that Al, Cr, Si, and N exist in a 1:1:1:1 ratio.
[0041] When a first coating 23 containing the metal (e.g., Ti) contained in the intermediate layer 22 is placed on top of the intermediate layer 22, the adhesion between the intermediate layer 22 and the coating 20 is high. As a result, the coating 20 is difficult to peel off from the intermediate layer 22, and therefore the coating 20 has high durability.
[0042] like Figure 4 As shown, the first coating 23 has a plurality of first layers 23a and a plurality of second layers 23b. The first coating 23 has a striped structure in which the first layers 23a and the second layers 23b are alternately stacked in the thickness direction. The second layers 23b are formed on the first layers 23a.
[0043] The thicknesses of the first layer 23a and the second layer 23b can be less than 50 nm each. The relatively thin first layer 23a and the second layer 23b have low residual stress and are less prone to peeling, cracking, etc., thus increasing the durability of the coating 20.
[0044] The second coating 24 can also contain Ti, Si, and N. That is, the second coating 24 can also be a nitride layer (TiSiN layer) containing Ti and Si. It should be noted that the term "TiSiN layer" means that Ti, Si, and N exist in any proportion, and does not necessarily mean that Ti, Si, and N exist in a 1:1:1 ratio.
[0045] Therefore, for example, when the coefficient of friction of the second coating 24 is low, the corrosion resistance of the coated tool 1 can be improved. Additionally, for example, when the hardness of the second coating 24 is high, the wear resistance of the coated tool 1 can be improved. Furthermore, for example, when the oxidation initiation temperature of the second coating 24 is high, the oxidation resistance of the coated tool 1 can be improved.
[0046] The second coating 24 may also have a striped structure with at least two layers located in the thickness direction. Each layer of the striped structure of the second coating 24 may contain, for example, Ti, Si, and N. In this case, the content of Ti (hereinafter referred to as "Ti content"), Si (hereinafter referred to as "Si content"), and N (hereinafter referred to as "N content") in the second coating 24 may be repeatedly increased or decreased along the thickness direction of the second coating 24. The total content of Ti and Si in the second coating 24 may be 98 atomic% or more. Furthermore, the second coating 24 may also have a third and fourth layer alternately arranged in the thickness direction.
[0047] (Coating manufacturing method)
[0048] The coating 20 can be formed, for example, by physical vapor deposition. Examples of physical vapor deposition methods include ion plating and sputtering. As an example, when the coating is formed by ion plating, the coating can be formed by the following method.
[0049] First, an example of a method for preparing the first coating 23 by ion plating is shown. First, as an example, metal targets of Cr, Si, and Al, or composite alloy targets or sintered targets are prepared.
[0050] Next, the target, which serves as the metal source, is evaporated and ionized using methods such as arc discharge or glow discharge. The ionized metal reacts with nitrogen gas (N2) from a nitrogen source and is deposited onto the surface of the substrate. Through these steps, an AlCrSiN layer can be formed.
[0051] In the above steps, the temperature of the substrate can be set to 500-550℃, the nitrogen pressure can be set to 1.0-6.0Pa, a DC bias voltage of -50 to -200V can be applied to the substrate, and the arc discharge current can be set to 100-200A.
[0052] The composition of the first coating 23 can be adjusted by independently controlling the voltage and current values applied to each of the aluminum metal target, chromium metal target, aluminum-silicon composite alloy target, and chromium-silicon composite alloy target during arc discharge and glow discharge. Furthermore, the coating composition can also be adjusted by controlling the coating time and atmosphere pressure. In one embodiment, the ionization amount of the target metal can be varied by changing the voltage and current values during arc discharge and glow discharge. Additionally, the ionization amount of the target metal can be periodically varied by periodically changing the current value during arc discharge and glow discharge for each target. The current value during arc discharge and glow discharge of the target is periodically changed at intervals of 0.01 to 0.5 min, thereby periodically varying the ionization amount of the target metal. Thus, the content ratio of each metal element in the thickness direction of the coating can be configured to vary periodically.
[0053] During the above-described process, the composition of Al, Si, and Cr is changed by reducing the amount of Al and Si and increasing the amount of Cr. Then, the composition of Al, Si, and Cr is changed by increasing the amount of Al and Si and decreasing the amount of Cr, thereby enabling the fabrication of a first coating 23 having a first layer 23a and a second layer 23b.
[0054] Next, an example of a method for manufacturing the second coating 24, which is the TiSiN layer, will be described.
[0055] The second coating 24 can also be formed by physical vapor deposition, just like the first coating 23. As an example, firstly, a Ti metal target and a Ti-Si composite alloy target are prepared. Furthermore, by independently controlling the voltage and current values of the arc discharge and glow discharge applied to each of the prepared targets, it is possible to fabricate a second coating 24 with a striped structure.
[0056] In the above process, the temperature of the substrate can be set to 500-600℃, the nitrogen pressure can be set to 1.0-6.0Pa, a DC bias voltage of -50--200V can be applied to the substrate, the arc discharge current can be set to 100-200A, and the change period of the arc current can be set to 0.01-0.5min.
[0057] (Middle layer 22)
[0058] Intermediate layer 22 may also be located between substrate 10 and coating 20. Specifically, intermediate layer 22 is in contact with the upper surface of substrate 10 on one side (the lower surface in this case) and with the lower surface of coating 20 (first coating 23) on the other side (the upper surface in this case).
[0059] The adhesion between the intermediate layer 22 and the substrate 10 is stronger than the adhesion between the intermediate layer 22 and the coating 20. Examples of metallic elements possessing this property include Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, Si, Y, and Ti. The intermediate layer 22 contains at least one of the aforementioned metallic elements. For example, the intermediate layer 22 may also contain Ti. It should be noted that Si is a half-metal element, but in this specification, half-metal elements are also included among metallic elements.
[0060] When the intermediate layer 22 contains Ti, the Ti content in the intermediate layer 22 can be 1.5 atomic% or more. For example, the Ti content in the intermediate layer 22 can be 2.0 atomic% or more.
[0061] The intermediate layer 22 may also contain metal elements other than those mentioned above (Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, Si, Y, Ti). However, from the viewpoint of bonding with the substrate 10, the intermediate layer 22 may contain at least 95 atomic% of the aforementioned metal elements. More preferably, the intermediate layer 22 may contain at least 98 atomic% of the aforementioned metal elements. It should be noted that the proportion of metal components in the intermediate layer 22 can be determined, for example, by analysis using an EDS (energy dispersive X-ray spectrometer) attached to a STEM (scanning transmission electron microscope).
[0062] Thus, in the coated cutting tool 1 of this embodiment, by providing an intermediate layer 22 between the substrate 10 and the coating 20, which has a higher wettability with the substrate 10 than with the coating 20, the adhesion between the substrate 10 and the coating 20 can be improved. It should be noted that the adhesion between the intermediate layer 22 and the coating 20 is also high, so it is less likely that the coating 20 will peel off from the intermediate layer 22.
[0063] It should be noted that the thickness of the intermediate layer 22 can be, for example, greater than 0.1 nm and less than 20.0 nm.
[0064] Figure 5 This is a schematic enlarged view of the interface area between the substrate 10 and the first coating 23. Figure 5 This represents the interface region between the substrate 10 and the first coating 23 in a cross section perpendicular to the surface of the substrate 10.
[0065] like Figure 5As shown, the intermediate layer 22 located at the interface region between the substrate 10 and the first coating 23 is mostly located above the WC particles 10a contained in the substrate 10 and the binder phase 10b.
[0066] Specifically, the maximum value (atm%) of Ti obtained from elemental analysis in the direction transversely from the first coating 23 to the WC particles 10a is set as the Ti(WC) value, and the maximum value (atm%) of Ti obtained from elemental analysis in the direction transversely from the first coating 23 from WC to the binder phase 10b is set as the Ti(Co) value. Furthermore, the ratio of the Ti(WC) value to the Ti(Co) value (Ti(Co) value / Ti(WC) value) is set as the Ti(Co / WC) ratio. In this case, the Ti(Co / WC) ratio of the coated tool 1 of the embodiment is 0.8 or less.
[0067] Conventionally, a first coating composed of at least one element selected from the group consisting of Al, Cr, Si, Group 4 elements, Group 5 elements, and Group 6 elements, and at least one element selected from the group consisting of C and N, has room for improvement in its adhesion to WC particles. On the other hand, Ti has good adhesion to both the first coating and the WC particles. Therefore, as in the coated cutting tool 1 of the embodiment, by introducing an intermediate layer 22 containing Ti between the first coating 23 and the WC particles 10a, the adhesion between the substrate 10 and the first coating 23 can be improved.
[0068] The intermediate layer 22 having the above-described structure can be obtained, for example, by the following manufacturing method.
[0069] In 8×10 -3 ~1×10 -4 The substrate is heated to a surface temperature of 500–600 °C under reduced pressure (Pa). Next, argon gas is introduced as the atmosphere gas, and the pressure is maintained at 3.0 Pa. Then, the bias voltage is set to -400 V, and argon bombardment is performed for 11 minutes (argon bombardment pretreatment). Next, the pressure is reduced to 0.1 Pa, and an arc current of 100–200 A is applied to the Ti metal evaporation source for 0.3 minutes to form a Ti-containing layer as an intermediate layer on the substrate surface (Ti-containing layer film formation treatment). Then, argon gas is introduced as the atmosphere gas, the pressure is maintained at 3.0 Pa, the bias voltage is set to -200 V, and argon bombardment is performed for 1 minute (argon bombardment posttreatment).
[0070] <Pretreatment conditions before argon bombardment>
[0071] (1) Bias voltage: -400V
[0072] (2) Pressure: 3 Pa
[0073] (3) Processing time: 11 minutes
[0074] <Film Formation Conditions Containing Ti Layer 1>
[0075] (1) Arc current: 100~200A
[0076] (2) Bias voltage: -380 to -430V
[0077] (3) Pressure: 0.1 Pa
[0078] (4) Processing time: 0.3 minutes
[0079] <Argon bombardment post-treatment conditions 1>
[0080] (1) Bias voltage: -200V
[0081] (2) Pressure: 3 Pa
[0082] (3) Processing time: 1 minute
[0083] It should be noted that the Ti-containing layer may contain other metal elements based on diffusion. The Ti-containing layer may contain 50–98 atomic percent of metal elements other than Ti.
[0084] The bonding between the Co-containing binder phase and Ti is poor. Therefore, minimizing the amount of Ti on top of the Co-containing binder phase improves the overall bonding strength between the substrate and the coating. Thus, as in the coated tool 1 of the embodiment, by employing a structure in which more Ti in the binder phase 10b and the WC particles 10a contained in the substrate 10 are located on top of the WC particles 10a, the bonding strength between the substrate 10 and the first coating 23 can be improved, thereby enhancing the wear resistance and chip resistance of the coated tool 1.
[0085] In addition, in a cross section perpendicular to the surface of the substrate 10, at least a portion of the adhesive phase 10b may also be in contact with the first coating 23.
[0086] The first coating, composed of at least one element selected from the group consisting of Al, Cr, Si, Group IV elements, Group V elements, and Group VI elements, exhibits better adhesion to the Co-containing binder phase compared to the adhesion between the Co-containing binder phase and Ti. Therefore, when the structure is such that at least a portion of the binder phase 10b is in contact with the first coating 23, the adhesion between the substrate 10 and the first coating 23 can be further improved, and the wear resistance and chipping resistance of the coated tool 1 can be further enhanced.
[0087] The configuration in which at least a portion of the binder phase 10b is in contact with the first coating 23 can be manufactured, for example, under the following conditions.
[0088] <Pretreatment conditions before argon bombardment>
[0089] (1) Bias voltage: -400V
[0090] (2) Pressure: below 3 Pa
[0091] (3) Processing time: 11 minutes
[0092] <Film Formation Conditions Containing Ti Layer 2>
[0093] (1) Arc current: 130A or more and 180A or less
[0094] (2) Bias voltage: above -390V and below -410V
[0095] (3) Pressure: 0.1 Pa
[0096] (4) Processing time: 0.3 minutes
[0097] <Argon bombardment post-treatment conditions 2>
[0098] (1) Bias voltage: -200V
[0099] (2) Pressure: 3 Pa
[0100] (3) Processing time: 1 minute
[0101] The film formation condition 2 containing the Ti layer and the argon bombardment treatment condition 2 were alternately repeated more than once.
[0102] In addition, the thickness of the Ti-containing region on the WC particle 10a in the interface region, i.e., the intermediate layer 22 on the WC particle 10a, can be more than 1 nm and less than 15 nm.
[0103] If the thickness of the intermediate layer 22 is 1 nm or more, the bonding effect between the first coating 23 and the WC particles 10a can be further enhanced. If the thickness of the intermediate layer 22 is 15 nm or less, the generation / development of cracks from the intermediate layer 22 can be suppressed. Therefore, by setting the thickness of the intermediate layer 22 on the WC particles 10a to be 1 nm or more and 15 nm or less, the bonding force between the substrate 10 and the first coating 23 can be further improved, and the wear resistance and chipping resistance of the coated tool 1 can be further improved.
[0104] The intermediate layer 22 on the WC particle 10a with a thickness of 1 nm or more and 15 nm or less can be manufactured, for example, under the following conditions.
[0105] <Pretreatment conditions before argon bombardment>
[0106] (1) Bias voltage: -400V
[0107] (2) Pressure: below 3 Pa
[0108] (3) Processing time: 11 minutes
[0109] <Film Formation Conditions Containing Ti Layer 3>
[0110] (1) Arc current: 100A to 180A and below
[0111] (2) Bias voltage: -400V
[0112] (3) Pressure: 0.1 Pa
[0113] (4) Processing time: 0.3 minutes
[0114] <Argon bombardment post-treatment condition 3>
[0115] (1) Bias voltage: -200V
[0116] (2) Pressure: 3 Pa
[0117] (3) Processing time: 1 minute
[0118] The film formation condition 3 containing the Ti layer and the argon bombardment treatment condition 3 were alternately repeated more than once and less than 20 times.
[0119] <Cutting Tools>
[0120] Next, refer to Figure 6 The structure of the cutting tool having the above-described coated tool 1 will be described. Figure 6 This is a front view showing an example of a cutting tool used in an embodiment.
[0121] like Figure 6 As shown, the cutting tool 100 of the embodiment has a coated tool 1 and a tool holder 70 for fixing the coated tool 1.
[0122] The handle 70 is from the first end ( Figure 6 The upper end of the middle) faces the second end ( Figure 6 A rod-shaped component extending from the lower end of the handle. The handle 70 is, for example, made of steel or cast iron. In particular, it is preferred to use these components. High-performance steel.
[0123] The tool holder 70 has a tool groove 73 at its first end. The tool groove 73 is the part for mounting the coated tool 1, and has a mounting surface intersecting the rotation direction of the material being cut and a constraint side inclined relative to the mounting surface. A threaded hole for screwing into the screw 75, which will be described later, is provided on the mounting surface.
[0124] The coated cutting tool 1 is located in the tool slot 73 of the tool holder 70 and is mounted to the tool holder 70 by a screw 75. That is, the screw 75 is inserted into the through hole 5 of the coated cutting tool 1, and the front end of the screw 75 is inserted into the threaded hole formed in the mounting surface of the tool slot 73, so that the threads are screwed together. Thus, the coated cutting tool 1 is mounted to the tool holder 70 in such a way that the cutting edge portion protrudes outward from the tool holder 70.
[0125] In the embodiment, a cutting tool for so-called turning is illustrated. Examples of turning include, for instance, internal diameter machining, external diameter machining, and grooving. It should be noted that the cutting tool is not limited to tools used in turning. For example, the coated tool 1 can be used as a cutting tool for milling. Examples of cutting tools for milling include, for instance, end mills such as face mills, front end mills, side end mills, and grooving end mills, as well as end mills such as single-flute end mills, multi-flute end mills, tapered end mills, and ball end mills.
[0126] Example
[0127] The embodiments of this disclosure are described in detail below. It should be noted that this disclosure is not limited to the embodiments shown below.
[0128] Samples No. 1 to No. 20, with coatings on a substrate made of WC-based cemented carbide, were prepared. The preparation conditions for the intermediate layer of samples No. 1 to No. 20 are as follows: Figure 7 As shown. It should be noted that samples No. 1 to No. 20, samples No. 1 to No. 4, No. 6 to No. 9, No. 11, No. 14, and No. 17 correspond to embodiments of this disclosure, while samples No. 5, No. 10, No. 12, No. 13, No. 15, No. 16, and No. 18 to No. 20 correspond to comparative examples. Furthermore, Figure 7 The “repetition count” shown is the repetition count of the above group when the intermediate layer formation process and the Ar bombardment post-processing are set as a group of 1.
[0129] Figure 8 This table summarizes the average composition of the first coating, the presence or absence of Ti in the intermediate layer, the Ti (Co / WC) ratio, and the average thickness of the Ti-containing layer on the WC particles for samples No.1 to No.20.
[0130] like Figure 8 As shown, the first coating of samples No.1 to No.10 is an AlCrSiN layer. Specifically, the average composition of the first coating of samples No.1 to No.10 is (Al... 50 Cr 39 Si 11The first coating of samples No. 11 to No. 13 is an AlCrN layer. Specifically, the average composition of the first coating of samples No. 11 to No. 13 is (Al... 50 Cr 50 The first coating of samples No. 14 to No. 16 and No. 20 is a TiAlN layer. Specifically, the average composition of the first coating of samples No. 14 to No. 16 and No. 20 is (TiAlN). 50 Al 50 The first coating of samples No. 17 to No. 19 is a TiAlSiN layer. Specifically, the average composition of the first coating of samples No. 17 to No. 19 is (Ti 50 Al 40 Si 10 )N.
[0131] Samples No. 1 through No. 20, and samples No. 1 through No. 9, No. 11, No. 12, No. 14, No. 15, No. 17, and No. 18, have a Ti-containing interlayer. In contrast, samples No. 10, No. 13, No. 16, and No. 19 do not have an interlayer. Furthermore, sample No. 20 does not have a Ti-containing interlayer, but it does have a Cr-containing interlayer.
[0132] For samples No.1 to No.9, No.11, No.12, No.14, No.15, No.17, and No.18 containing a Ti-containing intermediate layer, the Ti(Co / WC) ratio is as follows: Sample No.1 is 0.1, Sample No.2 is 0.5, Sample No.3 is 0.6, Sample No.4 is 0.8, Sample No.5 is 1, Sample No.6 is 0.7, Sample No.8 is 0.6, Sample No.9 is 0.8, Sample No.11 is 0.5, No.12 is 1, No.14 is 0.5, No.15 is 1, No.17 is 0.5, and No.18 is 1. In addition, the average thickness of the Ti-containing layer on the WC particles is as follows: 11 nm for sample No.1, 8 nm for sample No.2, 7 nm for sample No.3, 6 nm for sample No.4, 10 nm for sample No.5, 9 nm for sample No.6, 15 nm for sample No.8, 18 nm for sample No.9, 8 nm for sample No.11, 6 nm for sample No.12, 8 nm for sample No.14, 6 nm for sample No.15, 8 nm for sample No.17, and 6 nm for sample No.18.
[0133] Figure 9This table summarizes the results of oxidation, abrasion, and peel tests on samples No. 1 to No. 20. The test conditions for oxidation, abrasion, and peel tests are as follows.
[0134] <Oxidation Test>
[0135] For the AlCr-based coatings of samples No. 1 to No. 13, the following oxidation test was conducted: a specified intermediate layer formation treatment was performed on the platinum wire, and then the coating was formed to a thickness of 3 μm. The resulting coated platinum wire was then exposed to air at 1000°C for 1 hour. For the Ti-based coatings of samples No. 14 to No. 20, the following oxidation test was conducted: a specified intermediate layer formation treatment was performed on the platinum wire, and then the coating was formed to a thickness of 3 μm. The resulting coated platinum wire was then exposed to air at 800°C for 1 hour.
[0136] The platinum wire after the experiment was cross-sectioned, and the film condition was observed from the cross-section to determine the thickness of the oxide film. It should be noted that the thickness of the oxide film indicates better oxidation resistance.
[0137] Wear Test
[0138] The wear test was conducted using a 2-flute superhard ball end mill (model: 2KMBL0200-0800-S4) under the following conditions.
[0139] (1) Cutting method: Groove machining
[0140] (2) Material being cut: SKD11H
[0141] (3) Feed rate fz: 1320 mm / min
[0142] (4) Incision: ap 0.08mm × ae 0.20mm
[0143] (5) Evaluation method: The wear of the cross face after 20m cutting was measured by microscope.
[0144] <Peeling Test>
[0145] Peel tests were performed using a scratch testing machine. The load range was 20–150 N, and the evaluation was based on the load at which peeling occurred.
[0146] like Figure 9As shown, for samples No. 1–No. 4, No. 6–No. 9, No. 11, No. 14, and No. 17, which have a Ti-containing intermediate layer and a Ti(Co / WC) ratio of 0.8 or less, the film exhibits higher adhesion and higher wear resistance compared to samples with a Ti(Co / WC) ratio greater than 0.8. In particular, for samples with an average Ti-containing layer thickness of 15 nm or less on WC particles and an average composition of the first coating of (Al... 50 Cr 40 Si 10 Samples No.1 to No.4 and No.6 to No.9 of N exhibit excellent oxidation resistance, abrasion resistance, and adhesion to the coating.
[0147] <EDX Surface Analysis>
[0148] For sample No. 2, surface analysis based on EDX (energy dispersive X-ray diffraction) was performed. The analysis conditions are as follows.
[0149] (1) Sample pretreatment: using the FIB method (μ-sampling method) to form thin sheets
[0150] (2) Elemental analysis (surface analysis)
[0151] (3) Scanning transmission electron microscope: JEM-ARM200F, manufactured by Nippon Electronics.
[0152] (4) Accelerating voltage: 200kV
[0153] (5) Beam diameter: approximately
[0154] (6) Elemental analysis apparatus: JED-2300T
[0155] (7) X-ray detector: Si drift detector
[0156] (8) Energy resolution: approximately 140 eV
[0157] (9) X-ray extraction angle: 21.9°
[0158] (10) Solid angle: 0.98sr
[0159] (11) Number of pixels to be entered: 256×256
[0160] Figure 10 This is a scanning transmission electron microscope image of the coated cutting tool from the embodiment. Specifically, Figure 10 The image shows a scanning transmission electron microscope (HAADF-STEM) image of the interface region between the substrate and the first coating in a cross section perpendicular to the surface of the substrate.
[0161] in addition, Figures 11-13 Indicates and Figure 10 The image shown is a scanning transmission electron microscope image of elemental mapping in the same region. Specifically, Figure 11 This is a WC mapping image of the coated cutting tool in the embodiment. Figure 12 This is a Co-mapping image of the coated cutting tool in the embodiment. Figure 13 This is a Ti mapping image of the coated cutting tool in the embodiment.
[0162] like Figures 11-13 As shown, in the coated cutting tool of the embodiment, the Ti located at the interface region between the substrate and the first coating is mostly located above the WC in the WC and Co contained in the substrate.
[0163] In addition, such as Figure 12 As shown, in the coated cutting tool of the embodiment, at least a portion of the binder phase containing Co is in contact with the first coating.
[0164] <Line Extraction from EDX Analysis Data>
[0165] Furthermore, for the samples manufactured using the above-described manufacturing method, the range from the first coating to the line transverse to the WC particles (hereinafter referred to as "extraction range on WC") and the range from the first coating to the line transverse to the binder phase (hereinafter referred to as "extraction range on Co") were extracted from the EDX analysis data (area analysis data), and the Ti content was measured for each extraction range. The analytical conditions for the extracted EDX analysis data were the same as those for the area analysis described above.
[0166] Figure 14 This is a graph showing the extraction range on WC and the extraction range on Co. For example... Figure 14 As shown, a region with a length of 50.0 nm along the direction from the first coating to the transverse direction of the WC particles is defined as the WC extraction range. The starting point (0.0 nm) of the extraction range on WC is located at the first coating, and the ending point (50.0 nm) is located at the WC particles.
[0167] Additionally, a range of 50.0 nm in length along the direction from the first coating to the binder phase containing Co is defined as the Co extraction range. The starting point (0.0 nm) of the Co extraction range is located in the first coating, and the ending point (50.0 nm) is located in the binder phase.
[0168] Figure 15 This is a graph showing the determination results of Ti content within the extraction range on WC and the extraction range on Co. Figure 15 In the figure, hollow circles represent the amount of Ti measured in the WC extraction range, and black circles represent the amount of Ti measured in the Co extraction range.
[0169] Here, the maximum value of Ti amount (atm%) obtained by elemental analysis of the extraction range on WC is set as the Ti(WC) value, and the maximum value of Ti amount (atm%) obtained by elemental analysis of the extraction range on Co is set as the Ti(Co) value. Figure 15 As shown, the Ti(WC) value is approximately 2.55 atm%, and the Ti(Co) value is 1.35 atm%. Furthermore, the ratio of the Ti(WC) value to the Ti(Co) value (Ti(Co) value / Ti(WC) value) is approximately 0.53.
[0170] Thus, in the coated cutting tool of the embodiment, the ratio of Ti(WC) value to Ti(Co) value (Ti(Co / WC) ratio) is 0.8 or less.
[0171] As described above, the coated cutting tool of the embodiment (for example, coated cutting tool 1) has a substrate (for example, substrate 10) made of a WC-based cemented carbide with WC particles (for example, WC particles 10a) as the hard phase component and Co as the binder phase (for example, binder phase 10b) as the main component, and a first coating located on the substrate (for example, first coating 23). The first coating is composed of at least one element selected from the group consisting of Al, Cr, Si, Group IV elements, Group V elements, and Group VI elements, and at least one element selected from the group consisting of C and N. In the interface region between the substrate and the first coating in a cross section perpendicular to the surface of the substrate, the maximum value (atm%) of Ti obtained by elemental analysis in the direction from the first coating to the cross section of the WC particles is set as the Ti(WC) value, the maximum value (atm%) of Ti obtained by elemental analysis in the direction from the first coating to the cross section of the binder phase is set as the Ti(Co) value, and the ratio of Ti(WC) value to Ti(Co) value (Ti(Co) value / Ti(WC) value) is set as the Ti(Co / WC) ratio, and the Ti(Co / WC) ratio is 0.8 or less.
[0172] Therefore, the coated cutting tool according to the embodiment can improve the adhesion between the coating and the substrate.
[0173] It should be noted that, Figure 1 The shape of the coated tool 1 shown is merely an example and is not limited to the shape of the coated tool of this disclosure. The coated tool of this disclosure may also have, for example, a rod-shaped body having a rotation axis and extending from a first end to a second end; a cutting edge located at the first end of the body; and a groove extending spirally from the cutting edge toward the second end of the body.
[0174] Further effects and variations can be readily derived by those skilled in the art. Therefore, the invention is not limited to the specific detailed and representative embodiments described and illustrated above. Thus, various modifications can be made without departing from the spirit or scope of the overall concept of the invention as defined by the appended technical solutions and their equivalents.
[0175] Explanation of reference numerals in the attached figures
[0176] 1 Coated cutting tools
[0177] 2. Blade body
[0178] 5 Through holes
[0179] 10 Matrix
[0180] 10a WC particles
[0181] 10b binder phase
[0182] 20 Coatings
[0183] 22 Intermediate Layer
[0184] 23 First Coating
[0185] 24 Second Coating
[0186] 70 Knife Handle
[0187] 73 Tool Groove
[0188] 75 screws
[0189] 100 Cutting tools.
Claims
1. A coated cutting tool having a substrate composed of a WC-based cemented carbide with WC particles as the hard phase and Co as the binder phase, and a first coating disposed on the substrate. The first coating is composed of at least one element selected from the group consisting of Al, Cr, Si, Group 4 elements, Group 5 elements, and Group 6 elements, and at least one element selected from the group consisting of C and N. In the interface region between the substrate and the first coating in a cross-section perpendicular to the surface of the substrate, The maximum value (atm%) of Ti obtained by elemental analysis in the direction from the first coating to the transverse section of the WC particles is set as the Ti(WC) value. The maximum value (atm%) of Ti obtained by elemental analysis in the direction from the first coating to the cross section of the binder phase is set as the Ti(Co) value. When the ratio of the Ti(WC) value to the Ti(Co) value (Ti(Co) value / Ti(WC) value) is set as the Ti(Co / WC) ratio, The Ti(Co / WC) ratio is below 0.
8.
2. The coated cutting tool according to claim 1, wherein, In the interface region, the thickness of the Ti-containing region on the WC particle is greater than 1 nm and less than 15 nm.
3. A cutting tool, wherein, The cutting tool has: A rod-shaped knife handle with a groove at the end; and The coated cutting tool according to claim 1 or 2, which is located within the cutting groove.