Coated tool and cutting tool

Abstract

The non-restrictive coated cutting tool of the present invention is a coated cutting tool provided with a base body and a coating layer positioned on the surface of the base body. The coating has a TiCNO layer and an Al2O3 layer. The Al2O3 layer is provided so as to be in contact with the TiCNO layer at a position farther from the base than the TiCNO layer. The TiCNO layer has a plurality of composite protrusions having first protrusions protruding toward the Al2O3 layer and second protrusions protruding from the first protrusions in a direction intersecting the protruding direction of the first protrusions. In a cross section orthogonal to the surface of the base, the average width (A) of the base of the first protrusions is 200-1200 nm, and the average length (B) of the first protrusions is 200-1000 nm. The non-limiting cutting tool is provided with a tool handle which extends from a first end to a second end and is provided with a clamping groove on the first end side, and the coating tool located in the clamping groove.

Description

[0001] [Cross-reference to related applications]

[0002] This application claims the benefit of priority from Japanese Patent Application No. 2022-177110 filed on November 4, 2022, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The invention relates to a coated tool and a cutting tool. Background Art

[0004] Coated tools are known in which an Al2O3 layer or the like is laminated via a bonding film on the surface of a substrate such as cemented carbide, cermet, or ceramic. Coated tools having a coating formed on the surface of a substrate are used as cutting tools or the like.

[0005] As cutting processing becomes more efficient, cutting tools are increasingly used for heavy intermittent cutting where the cutting edge is subjected to huge impact. Under such harsh cutting conditions, the coating is subjected to large impacts, which can easily lead to coating breakage and peeling. Therefore, in addition to wear resistance, the coating also needs to have improved breakage resistance.

[0006] In cutting tools, as a technique for improving fracture resistance, Japanese Patent Gazette No. 5303732 (Patent Document 1) discloses that a bonding film and an Al2O3 layer are formed in sequence, and dendritic projections extending toward the Al2O3 layer and branched projections connected to the dendritic projections are provided on the bonding film, thereby improving the bonding strength between the bonding film and the Al2O3 layer and suppressing the peeling of the coating. Patent Document 1 discloses that the dendritic projections are Ti(CO) or Ti(CNO), and the dendritic projections are (TiAl)(CNO), and describes that after the dendritic projections are formed, the flow of the raw material gas is stopped, and while the temperature is maintained, the pressure and the type of the raw material gas are changed to form dendritic projections having a composition different from that of the dendritic projections. Summary of the invention

[0007] A non-limiting coated tool of the present invention is a coated tool having a substrate and a coating located on the surface of the substrate. The coating has a TiCNO layer and an Al2O3 layer. The Al2O3 layer is arranged in contact with the TiCNO layer at a position farther from the substrate than the TiCNO layer. The TiCNO layer has a plurality of composite protrusions, each of which has a first protrusion protruding toward the Al2O3 layer and a second protrusion protruding from the first protrusion in a direction intersecting with the protruding direction of the first protrusion. In a cross section orthogonal to the surface of the substrate, the average width A of the base of the first protrusion is 200 to 1200 nm, and the average length B of the first protrusion is 200 to 1000 nm.

[0008] A non-limiting cutting tool of the present invention comprises: a tool holder extending from a first end toward a second end and having a groove at the first end; and the above-mentioned coated tool located in the groove. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 FIG. 1 is a perspective view showing a non-limiting coated tool of the present invention.

[0010] Figure 2 is with Figure 1 A cross-sectional view orthogonal to the substrate surface of the coated tool is shown.

[0011] Figure 3 It is magnified Figure 2 A diagram showing the vicinity of the boundary between the TiCNO layer and the Al2O3 layer.

[0012] Figure 4 It is used to illustrate Figure 1 A and B schematic diagrams of the first protrusion of the coated tool are shown.

[0013] Figure 5 It is used to illustrate Figure 1 Schematic diagrams of C and D of the second protrusions of the coated tool are shown.

[0014] Figure 6 It is used to illustrate Figure 1 Schematic diagrams of C and D of the second protrusions of the coated tool are shown.

[0015] Figure 7 is a cross-sectional view showing a non-limiting coated tool of the present invention, which is equivalent to Figure 3 .

[0016] Figure 8 is a perspective view showing a non-limiting cutting tool of the present invention. DETAILED DESCRIPTION

[0017] <Coated tools>

[0018] Hereinafter, a non-limiting coated tool 1 of the present invention will be described in detail using the accompanying drawings. However, in the following referenced figures, only the main components necessary for explaining the embodiment are simplified for the sake of convenience. Therefore, the coated tool 1 may have any structural components not shown in the referenced figures. In addition, the dimensions of the components in the figures do not faithfully represent the dimensions of the actual structural components and the dimensional ratios of the components. In addition, Figures 4 to 6 Although it is also a cross-sectional view perpendicular to the surface of the base body, hatching formed by oblique lines indicating that it is a cross section is omitted for visual ease of understanding.

[0019] Coated tool 1 Figure 1 and Figure 2 The non-limiting example shown may include a substrate 3 and a coating 7 located on a surface 5 of the substrate 3. The coating 7 may include a TiCNO layer 9 (titanium carbon nitride oxide layer) and an Al2O3 layer 11 (aluminum oxide layer). The Al2O3 layer 11 is disposed in contact with the TiCNO layer 9 at a position farther from the substrate 3 than the TiCNO layer 9.

[0020] TiCNO layer 9 Figure 3 As a non-limiting example, a plurality of composite protrusions 13 may be provided. Each of the plurality of composite protrusions 13 may include a first protrusion 15 protruding toward the Al2O3 layer 11, and a second protrusion 17 protruding from the first protrusion 15 toward a direction intersecting the protruding direction of the first protrusion 15. In this case, the TiCNO layer 9 and the Al2O3 layer 11 are difficult to be peeled off by the bite of the composite protrusion 13 and the Al2O3 layer 11.

[0021] Here, if Figure 3 and Figure 4 As a non-limiting example, in a cross section perpendicular to the surface 5 of the substrate 3 , the average width A of the base 19 of the first protrusions 15 may be 200 to 1200 nm, and the average length B of the first protrusions 15 may be 200 to 1000 nm.

[0022] The first protrusion 15 having the above-mentioned A and B has a relatively large overall size because both A and B are relatively large. The Al2O3 layer 11 provided in contact with the TiCNO layer 9 having such first protrusions 15 has a high texture coefficient Tc (006), and is easy to achieve a high degree of orientation. The Al2O3 layer 11 is easy to achieve the effect of a high degree of orientation, and the above-mentioned composite protrusion 13 and the Al2O3 layer 11 bite the effect, and the fracture resistance and wear resistance are easy to improve. Therefore, the wear resistance and fracture resistance of the coated tool 1 are high.

[0023] Furthermore, A may be greater than or equal to 400 nm. A may be less than or equal to 1000 nm. B may be greater than or equal to 400 nm. B may be less than or equal to 800 nm.

[0024] The width of the base 19 of the first protrusion 15 may be the width of the portion of the first protrusion 15 that is the protrusion start point. The average width A of the base 19 of the first protrusion 15 may be the average value of the widths of the bases 19 of 10 or more first protrusions 15. In addition, the length of the first protrusion 15 may be the length of the line segment connecting the width center portion 19a of the portion (base 19) that is the protrusion start point of the first protrusion 15 and the tip 15a of the first protrusion 15. The average length B of the first protrusion 15 may be the average value of the lengths of 10 or more first protrusions 15.

[0025] The base 19 of the first protrusion 15 may be the portion of the first protrusion 15 that is located closest to the base 3. In addition, in the cross section perpendicular to the surface 5 of the base 3, the first protrusion 15 may be triangular. In this case, the base of the triangular first protrusion 15 may be the base 19 of the first protrusion 15. In addition, the tip 15a of the first protrusion 15 may be the portion of the first protrusion 15 that is located farthest from the base 3. The tip 15a of the first protrusion 15 may also be pointed.

[0026] The measurement of A and B can be performed by cross-sectional observation using an electron microscope. An electron microscope can be used to photograph a cross section orthogonal to the surface 5 of the substrate 3 at a magnification of 15,000 times, and more than 10 composite protrusions 13 in the obtained electron microscope photograph can be extracted to measure A and B. As an electron microscope, for example, a scanning electron microscope (Scanning Electron Microscopy: SEM) and a transmission electron microscope (Transmission Electron Microscopy: TEM) can be listed. In addition, A and B do not need to be measured in multiple cross sections throughout the entire coated tool 1. It is sufficient to measure A and B in a cross section at any position of the coated tool 1. These aspects are also the same for C and D described later.

[0027] The relationship between A and B may satisfy (A / B)>1. In this case, since the average width A of the base 19 of the first protrusion 15 is relatively large, the overall size is large, and the strength of the first protrusion 15 is easily ensured. Therefore, the first protrusion 15 is less likely to be damaged.

[0028] At least one of the plurality of composite protrusions 13 may have a plurality of second protrusions 17. In this case, the TiCNO layer 9 and the Al2O3 layer 11 are more difficult to peel off. In addition, all of the plurality of composite protrusions 13 may have a plurality of second protrusions 17. The composite protrusion 13 having a plurality of second protrusions 17 means that a plurality of second protrusions 17 are located on one first protrusion 15.

[0029] like Figure 3 and Figure 5 As a non-limiting example, in a cross section perpendicular to the surface 5 of the substrate 3, the average width C of the base 21 of the second protrusion 17 can be 20 to 150 nm, and the average length D of the second protrusion 17 can be 20 to 150 nm. The second protrusion 17 having such C and D is unlikely to be cracked or damaged between the first protrusion 15. Therefore, the TiCNO layer 9 and the Al2O3 layer 11 are more difficult to peel off.

[0030] Furthermore, C may be greater than 40 nm. C may be less than 125 nm. D may be greater than 40 nm. D may be less than 120 nm.

[0031] The width of the base 21 of the second protrusion 17 may be the width of the portion of the second protrusion 17 that is the protrusion start point. The average width C of the base 21 of the second protrusion 17 may be the average value of the widths of the bases 21 of more than 10 second protrusions 17. In addition, the length of the second protrusion 17 may be the length of the line segment connecting the width center portion 21a of the portion (base 21) of the second protrusion 17 that is the protrusion start point and the tip 17a of the second protrusion 17. The average length D of the second protrusion 17 may be the average value of the lengths of more than 10 second protrusions 17. The measurement of C and D may also be performed by the same method as the measurement of A and B using an electron microscope as described above.

[0032] The base 21 of the second protrusion 17 may be a portion of the second protrusion 17 that is located closest to the first protrusion 15. In addition, in a cross section orthogonal to the surface 5 of the base 3, the second protrusion 17 may be a triangle. In this case, the base of the triangular second protrusion 17 may be the base 21 of the second protrusion 17. In addition, the tip 17a of the second protrusion 17 may be a portion of the second protrusion 17 that is located farthest from the first protrusion 15. The tip 17a of the second protrusion 17 may be pointed.

[0033] In a cross section orthogonal to the surface 5 of the substrate 3, the second protrusion 17 may have a first side 17b and a second side 17c extending from two points where the first protrusion 15 and the second protrusion 17 are joined toward a tip 17a of the second protrusion 17, respectively. Figure 5 As a non-limiting example, the first side 17b and the second side 17c may be in the shape of straight lines.

[0034] Furthermore, the first side 17b and the second side 17c may not be straight lines. For example, the first side 17b and the second side 17c may be curved lines, or may be a combination of straight lines and curved lines. Figure 6 In the non-limiting example shown, the first side 17b' and the second side 17c' are curved. Figure 6 As a non-limiting example, when the second protrusion 17' is not a standard triangle, the length of the line segment connecting the two points where the first protrusion 15 and the second protrusion 17' join can be used as the width of the base 21 of the second protrusion 17'. In addition, the length of the line segment connecting the width center portion 21a of the base 21 and the tip 17a of the second protrusion 17' can be used as the length of the second protrusion 17'.

[0035] In addition, Figure 6In the cross section shown, the outer edges of the first protrusion 15 and the second protrusion 17' are represented by curves. If these curves are smoothly connected and it is difficult to determine the boundary between the first protrusion 15 and the second protrusion 17', the boundary between the first protrusion 15 and the second protrusion 17', that is, the base 21 of the second protrusion 17' can also be determined according to the following steps.

[0036] For example, when the outer edges of the first protrusion 15 and the second protrusion 17' are both curved, Figure 6 In the cross section shown in the figure, two curves are shown from the tip 17a of the second protrusion 17' toward the first protrusion 15. At this time, the tangent line connecting the two curves is uniquely determined. The two tangent points of the two curves and the tangent lines are the boundaries between the first protrusion 15 and the second protrusion 17'. In this case, the portion of the tangent line sandwiched between the two tangent points corresponds to the base 21.

[0037] As described above, when it is difficult to determine the boundary between the first protrusion 15 and the second protrusion 17 in the cross section, it is sufficient to determine the tangent lines that touch both sides of the two outer edges extending from the tip 17a of the second protrusion 17 toward the first protrusion 15. In this way, the boundary between the first protrusion 15 and the second protrusion 17 can be confirmed, and the base 21 can also be determined.

[0038] When the outer edge of the first protrusion 15 in the cross section is a curve, the width of the base 19 of the first protrusion 15 can also be evaluated by the same evaluation method as described above. The base 19 of the first protrusion 15 can be determined by determining the tangent lines that touch the first protrusion 15 as a target and the two boundaries of the two first protrusions 15 adjacent to the first protrusion 15.

[0039] In the relationship between C and D, (C / D)>1 may be satisfied. In this case, the average width C of the base 21 of the second protrusion 17 becomes relatively large, so that the second protrusion 17 is less likely to be elongated and more likely to be in a stable shape. Therefore, cracks and damages are less likely to occur between the first protrusion 15 and the second protrusion 17.

[0040] The texture coefficient Tc (006) of the Al2O3 layer 11 may be 7.5 or more. In this case, it is easy to improve the fracture resistance and wear resistance. In addition, the Al2O3 layer 11 may have an α-type crystal structure.

[0041] The texture coefficient Tc (006) can be measured, for example, by X-ray diffraction (XRD) analysis. Specifically, based on the peak of the Al2O3 layer 11 analyzed by XRD analysis, the value represented by the following formula can be used as the orientation coefficient Tc (hkl). Then, the texture coefficient Tc (006) detected by measurement from the surface side of the Al2O3 layer 11 can be 7.5 or more.

[0042] Texture coefficient Tc(hkl) = {I(hkl) / I0(hkl)} / 〔(1 / 9)×Σ{I(HKL) / I0(HKL)}〕

[0043] Here, (HKL) refers to crystal planes of (012), (104), (110), (006), (113), (024), (116), (214), and (146).

[0044] I(HKL) and I(hkl) are peak intensities of peaks belonging to respective crystal planes detected in the XRD analysis of the Al 2 O 3 layer 11 .

[0045] I0(HKL) and I0(hkl) are the standard diffraction intensities of each crystal plane as described in JCPDS card No. 00-010-0173.

[0046] like Figure 3 As a non-limiting example, the TiCNO layer 9 may also have other protrusions 23 different from the composite protrusions 13. In this case, the composite protrusions 13 may account for more than 60% of all the protrusions. In this case, the composite protrusions 13 are the main protrusions. Therefore, it is easy to realize a coated tool 1 with high wear resistance and fracture resistance.

[0047] The upper limit of the ratio of the composite protrusions 13 may be, for example, 70%. The upper limit of the ratio of the composite protrusions 13 is not limited to the exemplified value. For example, the ratio of the composite protrusions 13 may be 100%.

[0048] The ratio of the composite protrusions 13 is a value calculated by the formula: (number of composite protrusions / total number of protrusions) × 100. The total number of protrusions is the sum of the number of composite protrusions 13 and the number of other protrusions 23. The other protrusions 23 can be measured by the same method as the first protrusions 15, and the length of the protrusions is 200 nm or more.

[0049] The total number of protrusions can be measured by cross-sectional observation using an electron microscope. For example, an electron microscope can be used to photograph a cross section orthogonal to the surface 5 of the substrate 3 at a magnification of 15,000 times, and the number of composite protrusions 13 and other protrusions 23 present within the range of 18.6μm×6μm of the obtained electron microscope photograph can be measured. In addition, the total number of protrusions can be 5 to 20 in one field of view of the electron microscope photograph. In addition, the total number of protrusions does not need to be measured over the entire coated tool 1 and in multiple cross sections. The total number of protrusions can be measured in one cross section at any position of the coated tool 1.

[0050] The first protrusion 15 and the second protrusion 17 may contain titanium, carbon, nitrogen and oxygen, and may have the same composition. In this case, cracks and damage are unlikely to occur between the first protrusion 15 and the second protrusion 17, and the bonding between the TiCNO layer 9 and the Al2O3 layer 11 is high compared to the case where the first protrusion 15 and the second protrusion 17 have different compositions.

[0051] The so-called homogeneous composition means that the difference between the constituent components is less than 5%. The difference between the constituent components may be less than 3%, or less than 1%. For example, if the same gas is used when forming the first protrusion 15 and the second protrusion 17, the first protrusion 15 and the second protrusion 17 with homogeneous compositions can be obtained.

[0052] Furthermore, the compositions of the first protrusions 15 and the second protrusions 17 may be different as necessary. For example, if gases having different compositions are used when forming the first protrusions 15 and the second protrusions 17, first protrusions 15 and second protrusions 17 having different compositions can be obtained.

[0053] The first protrusion 15 may protrude in a direction perpendicular to the surface 5 of the base 3, or may protrude in a direction inclined to the surface 5 of the base 3. Figure 4 As a non-limiting example, the second protrusion 17 may protrude from a region of the first protrusion 15 excluding the tip 15a of the first protrusion 15. In this case, the effect of the first protrusion 15 can be easily obtained.

[0054] The coating 7 is not limited to a specific thickness. For example, the average thickness of the TiCNO layer 9 can be set to 200 to 2000 nm. In this case, the hardness of the TiCNO layer 9 is difficult to decrease, and the Al2O3 layer 11 is easy to become an α-type crystal structure. The thickness of the TiCNO layer 9 is a value excluding the first protrusion 15 and the second protrusion 17. When the TiCNO layer 9 has other protrusions 23, the thickness of the TiCNO layer 9 is also a value excluding the other protrusions 23.

[0055] The average thickness of the Al 2 O 3 layer 11 may be set to 1 to 15 μm. The average thickness of the Al 2 O 3 layer 11 may be greater than the average thickness of the TiCNO layer 9 .

[0056] The thickness of the coating layer 7 can be measured by cross-sectional observation using an electron microscope. For example, the thickness can be measured at 10 or more measurement points at any position of each layer, and the average value can be calculated.

[0057] The TiCNO layer 9 may contain, for example, 30 to 70 atomic % of titanium, 1 to 70 atomic % of carbon, 1 to 35 atomic % of nitrogen, and 3 to 20 atomic % of oxygen. The TiCNO layer 9 may further contain aluminum at a ratio of less than 10 atomic %, and may further contain components such as chlorine and chromium at a ratio of 1 to 10 atomic %. The TiCNO layer 9 may also contain other trace components. The first protrusion 15 and the second protrusion 17 may have the same composition and may be within the above-mentioned composition range.

[0058] The elemental analysis can be performed, for example, by energy dispersive X-ray spectroscopy (EDS). The elemental analysis can also be performed by cross-sectional observation using EDS attached to an electron microscope.

[0059] The coating layer 7 may be located on the entire surface 5 of the substrate 3 or only on a portion thereof. That is, the coating layer 7 may be located on at least a portion of the surface 5 of the substrate 3 .

[0060] The coating layer 7 may be formed by chemical vapor deposition (CVD). In other words, the coating layer 7 may be a CVD film. Alternatively, the coating layer 7 may be a PVD film formed by physical vapor deposition (PVD).

[0061] As the material of the substrate 3, for example, cemented carbide, ceramics, and metals can be cited. As cemented carbide, for example, cemented carbide containing tungsten carbide (WC), and iron group metals such as cobalt (Co) or nickel (Ni) can be cited. As other cemented carbides, for example, Ti-based metal ceramics containing titanium carbonitride (TiCN) and iron group metals can be cited. As ceramics, for example, silicon nitride (Si3N4), aluminum oxide (Al2O3), diamond, and cubic boron nitride (cBN) can be cited. As metals, for example, carbon steel, high-speed steel, and alloy steel can be cited.

[0062] exist Figure 1 In FIG. 1 , a cutting insert is shown as a non-limiting example of the coated tool 1. In addition, the coated tool 1 is not limited to the cutting insert.

[0063] The coated tool 1 may include: a first surface 25 (upper surface); a second surface 27 (side surface) adjacent to the first surface 25 ; and a cutting edge 29 located on at least a portion of a ridgeline between the first surface 25 and the second surface 27 .

[0064] The first surface 25 may be a rake face. The first surface 25 may be entirely a rake face, or may be partially a rake face. For example, a region along the cutting edge 29 of the first surface 25 may be a rake face.

[0065] The second surface 27 may be a flank surface. The entire second surface 27 may be a flank surface, or a portion thereof may be a flank surface. For example, a region along the cutting edge 29 of the second surface 27 may be a flank surface.

[0066] The cutting edge 29 may be located at a part of the ridge portion or may be located at the entire ridge portion. The cutting edge 29 can be used for cutting a workpiece.

[0067] The coated tool 1 may have a through hole 31. When the coated tool 1 is held on the tool holder, the through hole 31 can be used to install a fixing bolt or a clamping member. The through hole 31 can be formed from the first surface 25 toward the surface (lower surface) located on the opposite side of the first surface 25, and can be opened in these surfaces. In addition, there is no problem in the configuration that the through hole 31 is opened in the mutually opposing areas of the second surface 27.

[0068] The coated tool 1 may be in the shape of a quadrilateral plate. In addition, the shape of the coated tool 1 is not limited to a quadrilateral plate. For example, the first surface 25 may also be in the shape of a triangle, a pentagon, a hexagon or a circle.

[0069] The coated tool 1 is not limited to a specific size. For example, the length of one side of the first surface 25 can be set to about 3 to 20 mm. In addition, the height from the first surface 25 to the surface (lower surface) located on the opposite side of the first surface 25 can be set to about 5 to 20 mm.

[0070] Next, another non-limiting coated tool 1A of the present invention will be described using the accompanying drawings. Hereinafter, the differences between the coated tool 1A and the coated tool 1 will be mainly described, and the detailed description of the points having the same structure as the coated tool 1 will be omitted. Therefore, in order to understand the structure of the coated tool 1A, the description of the coated tool 1 can be cited.

[0071] In the coated tool 1A, as Figure 7As a non-limiting example, the coating 7 may have a first TiCN layer 33, a second TiCN layer 35, a TiCNO layer 9, and an Al2O3 layer 11 in order from the substrate 3. In this case, the life of the coated tool 1A can be easily extended.

[0072] The first TiCN layer 33 may be a so-called MT (moderate temperature)-TiCN layer. The average thickness of the first TiCN layer 33 may be set to 2 to 15 μm. In this case, the first TiCN layer 33 has high wear resistance and fracture resistance. In addition, the titanium carbonitride crystals contained in the first TiCN layer 33 may be columnar crystals that are elongated along the thickness direction of the coating 7.

[0073] The second TiCN layer 35 may be a so-called HT (high temperature)-TiCN layer. The average thickness of the second TiCN layer 35 may be set to 10 to 900 nm.

[0074] The carbon content ratio of the second TiCN layer 35 relative to the total content of carbon and nitrogen contained therein may be less than the carbon content ratio of the first TiCN layer 33. In this case, the hardness of the first TiCN layer 33 is easily improved. As a result, the wear resistance and fracture resistance of the coated tool 1A are easily improved. In addition, the so-called carbon content ratio means the ratio of the carbon content to the total content of carbon (C) and nitrogen (N) contained therein [C / (C+N)].

[0075] The carbon content ratio of the first TiCN layer 33 can be 0.52-0.57, and the carbon content ratio of the second TiCN layer 35 can be 0.42-0.51. In this case, the wear resistance and fracture resistance of the coated tool 1A can be further improved. In addition, the carbon content of the first TiCN layer 33 can be 15-29 atomic%, and the nitrogen content can be 22-35 atomic%. In this case, the wear resistance and fracture resistance of the coated tool 1A can be further improved. The carbon content of the second TiCN layer 35 can be 13-24 atomic%, and the nitrogen content can be 23-35 atomic%. In this case, the bonding between the second TiCN layer 35 and the TiCNO layer 9 is high.

[0076] The first TiCN layer 33 may contain titanium at a ratio of 45 to 60 atomic %, carbon at a ratio of 15 to 29 atomic %, and nitrogen at a ratio of 22 to 35 atomic %. In this case, the wear resistance and fracture resistance of the coated tool 1A are higher. In addition, the second TiCN layer 35 may contain titanium at a ratio of 48 to 60 atomic %, carbon at a ratio of 10 to 20 atomic %, and nitrogen at a ratio of 15 to 25 atomic %. In this case, the second TiCN layer 35 is difficult to be destroyed, and the bonding between the second TiCN layer 35 and the TiCNO layer 9 is also high.

[0077] Oxygen may be present in the first TiCN layer 33 and the second TiCN layer 35, and the oxygen present in the second TiCN layer 35 is greater than the oxygen present in the first TiCN layer 33. For example, the first TiCN layer 33 may contain oxygen at a ratio of 0.5 atomic % or less. In addition, the second TiCN layer 35 may contain oxygen at a ratio of 1 to 10 atomic %.

[0078] The coating 7 may also have other layers. For example, the coating 7 may have a surface layer. The surface layer may be arranged farthest from the substrate 3 in the coating 7. For example, the surface layer may be located above the Al2O3 layer 11. The material of the surface layer may be titanium nitride. That is, the surface layer may be a TiN layer.

[0079] In addition, the material of the surface layer is not limited to titanium nitride. The material of the surface layer may be, for example, titanium carbonitride, titanium oxycarbonitride, chromium nitride, etc. In addition, the material of the surface layer may be colored. In this case, it is easy to distinguish whether the cutting edge 29 is used or not. The average thickness of the surface layer may be set to 0.1 to 3 μm.

[0080] The coating 7 may also have a bottom layer 37. The bottom layer 37 may be closest to the substrate 3 in the coating 7. For example, the bottom layer 37 may be located between the substrate 3 and the first TiCN layer 33. The bottom layer 37 may also function as a layer that inhibits the diffusion of components such as cobalt, carbon, and tungsten into the layer located above the bottom layer 37 when the substrate 3 contains these components. In addition, the bottom layer 37 may be a TiN layer. In addition, the bottom layer 37 may also be a TiCN layer formed by the carbon component of the substrate 3 diffusing into TiN. The average thickness of the bottom layer 37 may be set to 0.1 to 1 μm.

[0081] <Method for manufacturing coated cutting tools>

[0082] Next, a non-limiting method for manufacturing a coated tool according to the present invention will be described.

[0083] When manufacturing coated tools, a substrate can be first made. As a substrate, a substrate formed of cemented carbide is made, and this case is cited as an example for explanation. First, mixed metal powder, carbon powder, etc. can be appropriately added to inorganic powders such as carbides, nitrides, carbonitrides, oxides, etc. that can form a substrate by firing to obtain a mixed powder. Secondly, the mixed powder can be used to form a specified tool shape by known forming methods such as pressure forming, casting, extrusion, cold isostatic pressing, etc. Then, the obtained formed body can be fired in a vacuum or in a non-oxidizing atmosphere to obtain a substrate formed of cemented carbide. The surface of the obtained substrate can be subjected to grinding or honing.

[0084] Next, a coating can be formed on the surface of the obtained substrate by CVD to obtain a coated tool. The coating has a TiN layer (bottom layer), a first TiCN layer (MT-TiCN layer), a second TiCN layer (HT-TiCN layer), a TiCNO layer, an Al2O3 layer, and a TiN layer (surface layer) in order from the substrate. Taking this case as an example, the film formation conditions of each layer are described in turn.

[0085] When forming a TiN layer as the bottom layer, the film can be formed as follows. First, the reaction gas composition can be adjusted to include a mixed gas consisting of 0.5 to 10% by volume of titanium tetrachloride (TiCl4) gas, 10 to 60% by volume of nitrogen (N2) gas, and the rest of hydrogen (H2) gas. Then, this mixed gas is introduced into the furnace, and the film forming temperature can be set to 800 to 940°C and the pressure can be set to 8 to 50 kPa to form a TiN layer as the bottom layer.

[0086] The first TiCN layer (MT-TiCN layer) can be formed as follows. First, a mixed gas containing 0.5-10% by volume of titanium tetrachloride (TiCl4) gas, 5-60% by volume of nitrogen (N2) gas, 0.1-3% by volume of acetonitrile (CH3CN) gas, and the rest of hydrogen (H2) gas can be adjusted as the reaction gas composition. Then, this mixed gas is introduced into the furnace, and the film forming temperature can be set to a relatively low temperature of 780-880°C, and the pressure can be set to 5-25kPa to form the first TiCN layer. If the content ratio of acetonitrile (CH3CN) gas is made greater in the later stage of film formation than in the early stage of film formation, it is easy to make the average crystal width of the titanium carbonitride columnar crystals constituting the first TiCN layer larger on the surface side than on the substrate side.

[0087] The second TiCN layer (HT-TiCN layer) can be formed as follows. First, the reaction gas composition can be adjusted to include 1 to 4 volume % of titanium tetrachloride (TiCl4) gas, 5 to 20 volume % of nitrogen (N2) gas, 0.1 to 10 volume % of methane (CH4) gas, and the rest of hydrogen (H2) gas. Then, this mixed gas is introduced into the furnace, and the film forming temperature can be set to 900 to 990°C and the pressure can be set to 5 to 40 kPa to form the second TiCN layer. The second TiCN layer can be formed at a higher temperature than the first TiCN layer.

[0088] The TiCNO layer can be formed as follows. First, the reaction gas composition can be adjusted to include 3-15% by volume of titanium tetrachloride (TiCl4) gas, 0-50% by volume of nitrogen (N2) gas, 0.2-2% by volume of methane (CH4) gas, 0.5-2% by volume of acetonitrile (CH3CN) gas, 0.5-10% by volume of carbon monoxide (CO) gas, and the rest of hydrogen (H2) gas. Then, this mixed gas is introduced into the furnace, and the film forming temperature can be set to 900-990°C and the pressure can be set to 5-40kPa to form the TiCNO layer. If the TiCNO layer is formed under such film forming conditions, it is easy to form a composite protrusion having the first protrusion and the second protrusion with the above-mentioned structure. In addition, the texture coefficient Tc (006) of the Al2O3 layer can easily reach 7.5 or more.

[0089] The Al2O3 layer can be formed as follows. First, the reaction gas composition can be adjusted to include 3.5-15% aluminum chloride (AlCl3) gas by volume, 0.5-2.5% hydrogen chloride (HCl) gas by volume, 0.5-5% carbon dioxide (CO2) gas by volume, 0-1% hydrogen sulfide (H2S) gas by volume, and the rest of the gas is a mixed gas consisting of hydrogen (H2) gas. Then, this mixed gas is introduced into the furnace, and the film forming temperature can be set to 900-990°C and the pressure can be set to 5-20kPa to form the Al2O3 layer.

[0090] When forming a TiN layer as a surface layer, the film can be formed as follows. First, the reaction gas composition can be adjusted to include 0.1 to 10% by volume of titanium tetrachloride (TiCl4) gas, 10 to 60% by volume of nitrogen (N2) gas, and the rest of hydrogen (H2) gas. Then, this mixed gas is introduced into the furnace, and the film forming temperature can be set to 960 to 1100°C and the pressure can be set to 10 to 85 kPa to form a TiN layer as a surface layer.

[0091] In the obtained coated tool, grinding can be performed on at least the portion where the cutting edge is provided on the surface of the coating. In this case, the cutting edge is easy to become smooth. Therefore, the cut material is difficult to adhere, and it is easy to achieve a coated tool with higher wear resistance and fracture resistance.

[0092] The above-mentioned manufacturing method is an example of a method for manufacturing a coated tool. Therefore, the coated tool is of course not limited to being manufactured by the above-mentioned manufacturing method.

[0093] <Cutting tools>

[0094] Next, a non-limiting cutting tool 101 of the present invention will be described using the drawings, taking as an example a case where the cutting tool 1 described above is provided.

[0095] like Figure 8 As a non-limiting example, the cutting tool 101 may include: a tool holder 103 extending from a first end 103a toward a second end 103b and having a groove 105 on one side of the first end 103a; and a coated tool 1 located in the groove 105. When the cutting tool 101 includes the coated tool 1, stable cutting can be performed because the coated tool 1 has high wear resistance and fracture resistance.

[0096] The clamping groove 105 may be a portion for mounting the coated tool 1. The clamping groove 105 may be opened on the outer peripheral surface of the tool handle 103 and the end surface on one side of the first end 103a.

[0097] The coated tool 1 can be installed in the slot 105 by making the cutting edge 29 protrude outward from the tool holder 103. In addition, the coated tool 1 can be installed in the slot 105 by the fixing bolt 107. That is, the fixing bolt 107 is inserted into the through hole 31 of the coated tool 1, and the front end of the fixing bolt 107 is inserted into the threaded hole formed in the slot 105, and the threaded parts are tightened, thereby the coated tool 1 can be installed in the slot 105. At this time, the lower surface of the coated tool 1 can be in direct contact with the slot 105, and a gasket can be sandwiched between the coated tool 1 and the slot 105.

[0098] Examples of the material of the handle 103 include steel and cast iron. When the material of the handle 103 is steel, the handle 103 has high toughness.

[0099] exist Figure 8 In the example shown, a cutting tool 101 is illustrated for so-called turning processing. As turning processing, for example, inner diameter processing, outer diameter processing, and grooving processing can be cited. In addition, the use of the cutting tool 101 is not limited to turning processing. For example, there is no problem in using the cutting tool 101 for milling processing.

[0100] In the above, a non-limiting example of the coated tool 1, 1A and the cutting tool 101 of the present invention is described, but the present invention is not limited to the above-mentioned embodiment, and any embodiment is possible without departing from the gist of the present invention.

[0101] For example, in the above non-limiting embodiment, the coating tool 1 is used as the cutting tool 101, but the coating tool 1 can also be applied to other uses. Other uses include wear-resistant parts such as sliding parts or molds, tools such as excavators and knives, and impact-resistant parts.

[0102] In addition, the above-mentioned cutting tool 101 includes the coated tool 1 , but the present invention is not limited to this form. For example, the cutting tool 101 may include the coated tool 1A instead of the coated tool 1 .

[0103] In addition, the coated tool 1, 1A and the cutting tool 101 may have the following configurations.

[0104] (1) A coated tool comprises a substrate and a coating located on a surface of the substrate, wherein the coating comprises a TiCNO layer and an Al2O3 layer, the Al2O3 layer being arranged in contact with the TiCNO layer at a position farther from the substrate than the TiCNO layer, the TiCNO layer having a plurality of composite protrusions, the composite protrusions comprising a first protrusion protruding toward the Al2O3 layer, and a second protrusion protruding from the first protrusion in a direction intersecting the protruding direction of the first protrusion, wherein, in a cross section orthogonal to the surface of the substrate, an average width A of a base of the first protrusion is 200 to 1200 nm, and an average length B of the first protrusion is 200 to 1000 nm.

[0105] (2) In the coated tool of (1) above, the relationship between A and B may satisfy (A / B)>1.

[0106] (3) In the coated tool of (1) or (2) above, at least one of the plurality of composite protrusions may include a plurality of the second protrusions.

[0107] (4) In any one of the coated cutting tools described in (1) to (3) above, in the cross section, an average width C of the base of the second protrusions may be 20 to 150 nm, and an average length D of the second protrusions may be 20 to 150 nm.

[0108] (5) In the coated tool of (4) above, the relationship between C and D may satisfy (C / D)>1.

[0109] (6) In any of the coated cutting tools described in (1) to (5) above, the texture coefficient Tc(006) of the Al2O3 layer may be greater than 7.5.

[0110] (7) In any one of the coated cutting tools described in (1) to (6) above, the coating may include, in order from the substrate, a first TiCN layer, a second TiCN layer, the TiCNO layer, and the Al2O3 layer.

[0111] (8) A cutting tool comprising: a tool holder extending from a first end toward a second end and having a groove on the first end side; and a coated tool according to any one of (1) to (7) above located in the groove.

[0112] Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to the following Examples.

[0113] Example

[0114] [Sample No. 1 to 6]

[0115] <Manufacturing of coated tools>

[0116] First, a matrix is ​​prepared. Specifically, a mixed powder is obtained by mixing metal cobalt powder having an average particle size of 1.2 μm at 6 mass%, titanium carbide powder having an average particle size of 2 μm at 0.5 mass%, niobium carbide powder having an average particle size of 2 μm at 5 mass%, and tungsten carbide powder having an average particle size of 1.5 μm as the balance. The average particle size of each powder is a value measured by the Microtrac method.

[0117] Next, the obtained mixed powder is press-formed into a tool shape (CNMG120408) to obtain a formed body. Then, the obtained formed body is subjected to a dewaxing treatment and then fired in a non-oxidizing atmosphere to obtain a matrix formed of cemented carbide. In addition, the firing temperature is set to 1450-1600°C, the firing time is set to 1 hour, and an argon atmosphere is used as a non-oxidizing atmosphere. In addition, the obtained matrix is ​​brushed, and the portion serving as the cutting edge is subjected to R honing.

[0118] Next, a coating was formed on the surface of the obtained substrate by CVD method to obtain the sample coated tool shown in Table 1. In addition, for the sample shown in Table 1, a TiN layer as a bottom layer was first formed on the surface of the substrate, and a first TiCN layer (MT-TiCN layer), a second TiCN layer (HT-TiCN layer), a TiCNO layer and an Al2O3 layer were formed in sequence on the TiN layer. The film formation conditions of each layer are as follows.

[0119] (Film formation conditions of TiN layer (base layer))

[0120] First, a mixed gas containing 1 volume % of titanium tetrachloride (TiCl4) gas, 38 volume % of nitrogen (N2) gas, and the rest of hydrogen (H2) gas was adjusted as the reaction gas composition. Then, the mixed gas was introduced into the furnace, and the film forming temperature was set to 850°C and the pressure was set to 16 kPa. In addition, the film forming time was set to 180 minutes.

[0121] (Film formation conditions of the first TiCN layer (MT-TiCN layer))

[0122] First, a mixed gas containing 4 volume % of titanium tetrachloride (TiCl4) gas, 23 volume % of nitrogen (N2) gas, 0.4 volume % of acetonitrile (CH3CN) gas, and the rest of hydrogen (H2) gas was adjusted as the reaction gas composition. Then, the mixed gas was introduced into the furnace, and the film forming temperature was set to 850°C and the pressure was set to 9 kPa. In addition, the film forming time was set to 400 minutes.

[0123] (Film Formation Conditions of the Second TiCN Layer (HT-TiCN Layer))

[0124] First, a mixed gas containing 4 volume % of titanium tetrachloride (TiCl4) gas, 20 volume % of nitrogen (N2) gas, 8 volume % of methane (CH4) gas, and the rest of hydrogen (H2) gas was adjusted as the reaction gas composition. Then, the mixed gas was introduced into the furnace, and the film forming temperature was set to 950°C and the pressure was set to 13 kPa. In addition, the film forming time was set to 80 minutes.

[0125] (Film formation conditions of TiCNO layer)

[0126] As described in Table 1.

[0127] (Film formation conditions of Al2O3 layer)

[0128] First, the reaction gas composition was adjusted to include 3.7% aluminum chloride (AlCl3) gas by volume, 0.7% hydrogen chloride (HCl) gas by volume, 4.3% carbon dioxide (CO2) gas by volume, 0.3% hydrogen sulfide (H2S) gas by volume, and the rest hydrogen (H2) gas by volume. Then, the mixed gas was introduced into the furnace, and the film forming temperature was set to 950°C and the pressure was set to 7.5kPa. In addition, the film forming time was set to 380 minutes.

[0129] In the obtained coated tool, SEM observation was performed on the cross section perpendicular to the substrate surface. Then, following the method illustrated above, the average width A of the base of the first protrusion, the average length B of the first protrusion, the average width C of the base of the second protrusion, and the average length D of the second protrusion were measured. In addition, the measurements of A, B, C and D were performed in one cross section of the front cutting edge, with a magnification of 15,000 times and 10 measurements respectively. In addition, based on the measured A, B, C and D, (A / B) and (C / D) were calculated. In addition, following the method illustrated above, XRD analysis was performed on the obtained coated tool to measure the texture coefficient Tc (006) of the Al2O3 layer.

[0130] The measurement results are shown in Table 1. In addition, (A / B) is shown in the "A / B" column of Table 1. (C / D) is shown in the "C / D" column of Table 1.

[0131] For the coated tools of sample No. 1 to 4, the ratio of compound protrusions was measured according to the method illustrated above. As a result, compound protrusions accounted for 60 to 70% of all protrusions. In addition, the total number of protrusions was measured in one cross section of the front cutting edge. SEM was used as an electron microscope. The magnification was 15,000 times. The 18.6μm×6μm range of the obtained SEM photo was taken as one field of view. The total number of protrusions in one field of view of the SEM photo was 5 to 20.

[0132] <Evaluation>

[0133] The obtained coated cutting tools were subjected to a cutting test under the following conditions.

[0134] Processing method: Turning

[0135] Cutting speed: 300m / min

[0136] Feed speed: 0.3mm / rev

[0137] Cutting depth: 2mm

[0138] Cutting material: SCM435 φ200 round bar

[0139] Processing status: WET

[0140] The test results are shown in Table 1. In Table 1, "Cutting time until breakage occurs (min)" indicates the time until the tip breaks. In addition, "Cutting time until wear reaches 0.2 mm (min)" indicates the time until wear reaches 0.2 mm on the back face of the tip.

[0141]

Table 1

[0142]

[0143] Samples No. 1 to 4 showed higher wear resistance and fracture resistance than Samples No. 5 to 6.

[0144] Description of Reference Numerals

[0145] 1…Coated tools

[0146] 3…Matrix

[0147] 5…Surface

[0148] 7…Coating

[0149] 9…TiCNO layer

[0150] 11…Al2O3 layer

[0151] 13…Compound protrusions

[0152] 15…First protrusion

[0153] 15a… Tip

[0154] 17…Second protrusion

[0155] 17a… Tip

[0156] 17b…side 1

[0157] 17c…side 2

[0158] 19…base of the first protrusion

[0159] 19a…Central

[0160] 21…base of the second protrusion

[0161] 21a…Central

[0162] 23…Other protrusions

[0163] 25…side 1 (top)

[0164] 27… Second side (side)

[0165] 29…Cutting edge

[0166] 31…Through hole

[0167] 33…First TiCN layer

[0168] 35…Second TiCN layer

[0169] 37… bottom floor

[0170] 101…Cutting tools

[0171] 103…Handle

[0172] 103a…First End

[0173] 103b…Second end

[0174] 105…Card slot

[0175] 107…Fixing bolt

[0176] A...average width of the base of the first protrusion

[0177] B…average length of the first protrusion

[0178] C...average width of the base of the second protrusion

[0179] D…average length of the second protrusion

Claims

1. A coated tool comprising a substrate and a coating on the surface of the substrate, The coating comprises a TiCNO layer and an Al2O3 layer, The Al2O3 layer is provided in contact with the TiCNO layer at a position farther from the substrate than the TiCNO layer. The TiCNO layer has a plurality of composite protrusions, each of which has a first protrusion protruding toward the Al2O3 layer and a second protrusion protruding from the first protrusion toward a direction intersecting with the protrusion direction of the first protrusion. In a cross section perpendicular to the surface of the substrate, an average width A of the base of the first protrusions is 200 to 1200 nm, and an average length B of the first protrusions is 200 to 1000 nm.

2. The coated tool according to claim 1, wherein: In the relationship between A and B, (A / B)>1 is satisfied.

3. The coated tool according to claim 1 or 2, wherein: At least one of the plurality of composite protrusions has a plurality of the second protrusions.

4. The coated tool according to any one of claims 1 to 3, wherein: In the cross section, an average width C of the base of the second protrusion is 20 to 150 nm, and an average length D of the second protrusion is 20 to 150 nm.

5. The coated tool according to claim 4, wherein: In the relationship between the C and the D, (C / D)>1 is satisfied.

6. The coated tool according to any one of claims 1 to 5, wherein: The texture coefficient Tc (006) of the Al2O3 layer is greater than 7.

5.

7. The coated tool according to any one of claims 1 to 6, wherein: The coating layer comprises, in order from the substrate, a first TiCN layer, a second TiCN layer, the TiCNO layer and the Al 2 O 3 layer.

8. A cutting tool comprising: A tool handle extending from a first end toward a second end and having a slot on a side of the first end; and The coated cutting tool according to any one of claims 1 to 7 is located in the groove.

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