Coated and cutting tools

Abstract

The coated tool according to the present disclosure comprises a base body and a coating layer. The coating layer contains a plurality of crystal grains. The plurality of crystal grains have a plurality of regions provided with mutually different crystal orientations. The value of D2 / D1 is 0.55-0.95, where, when the crystal orientations of the plurality of crystal grains in the coating layer are analyzed from the planar direction of the coating layer using TEM electronic diffraction mapping and a first crystal grain map and a second crystal grain map are created, D1 is the average grain diameter of the crystal grains derived by taking a weighted average from the first crystal grain map according to area ratio, and D2 is the average grain diameter of the crystal grains derived by taking a weighted average from the second crystal grain map according to area ratio.

Description

[Technical Field]

[0001] The present disclosure relates to coated tools and cutting tools. [Background technology]

[0002] BACKGROUND ART As a tool used in cutting processes such as turning or milling, a coated tool is known in which the surface of a substrate made of cemented carbide, cermet, ceramics, or the like is coated with a coating layer to improve wear resistance and the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-50381 [Patent Document 2] Japanese Patent Application Publication No. 2018-30212 Summary of the Invention

[0004] A coated tool according to one embodiment of the present disclosure includes a substrate and a coating layer disposed on the substrate. The coating layer includes a plurality of crystal grains. The plurality of crystal grains include crystal grains having a plurality of regions with different crystal orientations. The average grain sizes D1 and D2 of the crystal grains in the coating layer, as defined by the following method, satisfy the relationship D2 / D1=0.55 to 0.95.

[0005] Definition of D1 and D2 The crystal orientation of multiple crystal grains in the coating layer is analyzed from the planar direction of the coating layer using a TEM electron diffraction mapping method, A first grain map is created by excluding the Σ3CSL (coincidence grain boundary) from the region where the misorientation between adjacent measurement points is 5° or more, and using this region as the grain boundary. The average grain size of the grains obtained by taking a weighted average based on the area ratio from the first grain map is defined as D1. A second grain map is created using the area where the misorientation between adjacent measurement points is 5° or more and the Σ3CSL (corresponding grain boundary) as the grain boundary, and the average grain size obtained by taking a weighted average based on the area ratio from the second grain map is defined as D2. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a perspective view showing an example of a coated tool according to an embodiment. [Figure 2] FIG. 2 is a side cross-sectional view showing an example of a coated tool according to an embodiment. [Figure 3] FIG. 3 is a schematic view showing an example of a coating layer according to an embodiment. [Figure 4] FIG. 4 is a cross-sectional view showing an example of the coating layer according to the first embodiment. [Figure 5A] FIG. 5A is a schematic diagram illustrating the Ti / Al ratio in the coating layer according to the first embodiment. [Figure 5B] FIG. 5B is a schematic diagram illustrating the Cr / Al ratio in the coating layer according to the first embodiment. [Figure 6A] FIG. 6A is a cross-sectional view showing an example of a first coating layer included in the coating layer according to the first embodiment. [Figure 6B] FIG. 6B is a cross-sectional view showing an example of a second coating layer included in the coating layer according to the first embodiment. [Figure 6C] FIG. 6C is a cross-sectional view showing an example of a third coating layer included in the coating layer according to the first embodiment. [Figure 7] FIG. 7 is a cross-sectional view showing an example of a coating layer according to the second embodiment. [Figure 8A] FIG. 8A is a schematic diagram illustrating the Ti / Al ratio in the coating layer according to the second embodiment. [Figure 8B] FIG. 8B is a schematic diagram illustrating the Cr / Al ratio in the coating layer according to the second embodiment. [Figure 9] FIG. 9 is a cross-sectional view showing an example of a fourth coating layer included in the coating layer according to the second embodiment. [Figure 10]FIG. 10 is a diagram schematically illustrating an example of a film forming apparatus for forming a coating layer on a substrate. [Figure 11] FIG. 11 is a front view showing an example of a cutting tool according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, modes for carrying out the coated tool and cutting tool according to the present disclosure (hereinafter referred to as "embodiments") will be described in detail with reference to the drawings. The coated tool and cutting tool according to the present disclosure are not limited to these embodiments. The embodiments can be appropriately combined within the scope of not causing any contradiction in the processing content. In the following embodiments, the same components are designated by the same reference numerals, and redundant explanations will be omitted.

[0008] In the following embodiments, expressions such as "constant," "orthogonal," "perpendicular," or "parallel" may be used, but these expressions do not necessarily mean "constant," "orthogonal," "perpendicular," or "parallel" in a strict sense. In other words, the above expressions allow for deviations due to, for example, manufacturing precision or installation precision.

[0009] BACKGROUND ART As a tool used in cutting processes such as turning or milling, a coated tool is known in which the surface of a substrate made of cemented carbide, cermet, ceramics, or the like is coated with a coating layer to improve wear resistance and the like.

[0010] The above-mentioned prior art has room for further improvement in terms of extending the tool life.

[0011] Therefore, there is a need to develop a technology that can overcome the above-mentioned problems and extend the tool life.

[0012] <Coated tools> Fig. 1 is a perspective view showing an example of a coated tool according to an embodiment. Fig. 2 is a side cross-sectional view showing an example of a coated tool according to an embodiment. As shown in Fig. 1, a coated tool 1 according to an embodiment has a tip body 2.

[0013] (Chip body 2) The chip body 2 has, for example, a hexahedral shape in which the upper and lower surfaces (surfaces intersecting with the Z axis shown in FIG. 1) are parallelogram-shaped.

[0014] One corner of the insert body 2 functions as a cutting edge portion. The cutting edge portion has a first surface (for example, an upper surface) and a second surface (for example, a side surface) connected to the first surface. In the embodiment, the first surface functions as a "rake surface" that scoops up chips generated by cutting, and the second surface functions as a "flank surface." A cutting edge is located on at least a portion of the ridge where the first surface and the second surface intersect, and the coated tool 1 cuts the workpiece by applying this cutting edge to the workpiece.

[0015] A through-hole 5 that passes through the tip body 2 from top to bottom is located in the center of the tip body 2. A screw 75 is inserted into the through-hole 5 to attach the coated tool 1 to a holder 70 (described later) (see FIG. 11).

[0016] As shown in FIG. 2, the chip body 2 has a base 10 and a coating layer 20.

[0017] (Base 10) The substrate 10 is formed of, for example, a cemented carbide. The cemented carbide contains W (tungsten), specifically WC (tungsten carbide). The cemented carbide may also contain Ni (nickel) or Co (cobalt). Specifically, the substrate 10 is made of a WC-based cemented carbide containing WC particles as the hard phase component and Co as the main component of the binder phase.

[0018] The substrate 10 may be formed of a cermet. The cermet contains, for example, Ti (titanium), specifically, TiC (titanium carbide) or TiN (titanium nitride). The cermet may also contain Ni or Co.

[0019] The substrate 10 may be formed of a cubic boron nitride sintered body containing cubic boron nitride (cBN) particles. The substrate 10 is not limited to cubic boron nitride (cBN) particles, but may also contain particles of hexagonal boron nitride (hBN), rhombohedral boron nitride (rBN), wurtzite boron nitride (wBN), or the like.

[0020] The substrate 10 may be made of ceramics. Examples of ceramics include Al2O3 (aluminum oxide). Types of Al2O3 include, for example, κ-Al2O3 and α-Al2O3. The ceramics may contain other elements in addition to aluminum oxide. For example, the ceramics may contain, in addition to aluminum oxide, at least one of magnesium (Mg), calcium (Ca), strontium (Sr), silicon (Si), and elements from Group 3 of the periodic table.

[0021] (Coating layer 20) The coating layer 20 is applied to the substrate 10 for the purpose of improving the abrasion resistance, heat resistance, etc. of the substrate 10. In the example of FIG. 2, the coating layer 20 covers the entire substrate 10. The coating layer 20 needs to be located at least on the substrate 10. When the coating layer 20 is located on the first surface (here, the top surface) of the substrate 10, the abrasion resistance and heat resistance of the first surface are high. When the coating layer 20 is located on the second surface (here, the side surface) of the substrate 10, the abrasion resistance and heat resistance of the second surface are high.

[0022] Here, a specific configuration of the coating layer 20 will be described with reference to FIG. 3. FIG. 3 is a schematic diagram showing an example of a coating layer according to an embodiment. The coating layer 20 according to the embodiment includes a plurality of crystal grains. For example, as shown in FIG. 3, the coating layer 20 includes a plurality of crystal grains 20a, 20b inside the coating layer 20. The inside of the coating layer 20 shown in FIG. 3 is a plane parallel to the surface of the substrate 10 on which the coating layer 20 is provided.

[0023] For example, analysis using a TEM electron diffraction mapping method (TEM ED-Map) can identify multiple crystal grains 20a, 20b inside the coating layer 20. More specifically, first, using the TEM electron diffraction mapping method, an electron beam probe is used to scan the interior of the coating layer 20 while measuring the electron diffraction pattern at each measurement point, thereby obtaining the crystal orientation corresponding to each measurement point in the crystal grain map of the coating layer 20. Next, if the difference in crystal orientation between adjacent measurement points in the crystal grain map of the coating layer 20 is, for example, 5° or more, a boundary line is drawn between the adjacent measurement points. Then, the area surrounded by the boundary line in the crystal grain map of the coating layer 20 can be identified as a crystal grain. In this case, crystal grains can be identified by dividing the area where the orientation difference between adjacent measurement points is 5° or more, excluding the Σ3CSL (coincidence grain boundary), into two cases: one where the area where the orientation difference between adjacent measurement points is 5° or more and the Σ3CSL (coincidence grain boundary) are considered to be the crystal grain boundary, and one where the area where the orientation difference between adjacent measurement points is 5° or more and the Σ3CSL (coincidence grain boundary) are considered to be the crystal grain boundary.

[0024] In the coating layer 20, as shown in FIG. 3, the multiple crystal grains 20a, 20b include a (single) crystal grain 20a (first crystal grain 20a) having multiple regions with different crystal orientations within the coating layer 20. The multiple crystal grains 20a, 20b include a (single) crystal grain 20b (second crystal grain 20b) having a substantially constant crystal orientation within the coating layer 20. All of the multiple crystal grains may be crystal grains 20a having multiple regions with different crystal orientations. The crystal grain 20a having multiple regions with different crystal orientations may be a single crystal grain 20a having regions with continuously changing crystal orientations. In the example shown in FIG. 3, the multiple crystal grains include a multiple first crystal grains 20a and a multiple second crystal grains 20b.

[0025] A first grain map is created using the region where the misorientation between adjacent measurement points is 5° or more, excluding the Σ3CSL (coincidence grain boundary), as the grain boundary, and the average grain size obtained by taking a weighted average based on the area ratio from the first grain map is defined as D1. Next, a second grain map is created using the region where the misorientation between adjacent measurement points is 5° or more and the Σ3CSL (coincidence grain boundary) as the grain boundary, and the average grain size obtained by taking a weighted average based on the area ratio from the second grain map is defined as D2. The value of D2 / D1 may be 0.55 to 0.95.

[0026] For example, analysis using TEM electron diffraction mapping can identify a single crystal grain 20a having multiple regions with different crystal orientations and / or a single crystal grain 20a having a region with continuously changing crystal orientations. More specifically, TEM electron diffraction mapping can be used to identify a single crystal grain 20a having multiple regions with different colors in an inverse pole figure orientation map within the coating layer 20 as a single crystal grain 20a having multiple regions with different crystal orientations. Similarly, TEM electron diffraction mapping can be used to identify a single crystal grain 20a having a region with continuously changing colors in an inverse pole figure orientation map within the coating layer 20 as a single crystal grain 20a having a region with continuously changing crystal orientations.

[0027] Using TEM electron diffraction mapping, misorientations of 5° or more are analyzed as grain boundaries. Furthermore, grain maps are created for cases where the Σ3CSL (correspondence grain boundary) is not considered a grain boundary and cases where the Σ3CSL (correspondence grain boundary) is considered a grain boundary. Next, for each grain map, the average grain size D1 and D2 are calculated by taking a weighted average based on the area ratio, and the D2 / D1 ratio can be determined. Furthermore, using the above grain map data and a crystal orientation analysis system, the average KAM (local misorientation) value for each grain can be output. In this case, adjacent pixels with a misorientation of 5° or more from the measurement center pixel are excluded from the KAM value calculation, as they are considered to be beyond the grain boundary from the single crystal where the measurement center pixel is located.

[0028] When the multiple crystal grains 20a, 20b include a single crystal grain 20a having multiple regions with different crystal orientations within the coating layer 20, crack propagation in the single crystal grain 20a having multiple regions with different crystal orientations can be reduced. In particular, setting the D2 / D1 value less than 0.95 increases the proportion of coincidence grain boundaries within the crystal, making it easier to suppress crack propagation within the coating layer 20 and improving the strength of the coating layer. Setting the D2 / D1 value greater than 0.55 prevents excessive variation in orientation within the crystal, suppressing plastic deformation of the coating layer 20 and providing good wear resistance. This prevents a decrease in chipping resistance and improves tool life. As a result, the life of the coated tool 1 can be extended.

[0029] In the coating layer 20 included in the multiple crystal grains 20a, 20b, when the average KAM (local misorientation) value of each crystal grain is calculated using the above-mentioned crystal grain map data and crystal orientation analysis system, the percentage of crystal grains showing an average KAM value of 1 or more may be 50% to 80%. In this case, it is possible to further reduce the propagation of cracks in a single crystal grain 20a having multiple regions with mutually different crystal orientations. Therefore, it is possible to further improve the fracture resistance of the coating layer 20. As a result, it is possible to further extend the life of the coated tool 1.

[0030] The multiple crystal grains 20a, 20b may contain composite nitrides. In this case, it is possible to obtain a coating layer 20 including a single crystal grain 20a having multiple regions with different crystal orientations. This makes it easier to improve the fracture resistance of the coating layer 20. As a result, it is easier to extend the life of the coated tool 1.

[0031] As shown in an example in FIG. 3, the first crystal grains 20a may be spaced apart from one another. In such a case, even if a crack develops in one of the first crystal grains 20a, the crack is unlikely to propagate to the other first crystal grains 20a. This makes it possible to prevent the crack from spreading over a wide area of ​​the coating layer 20. As a result, the life of the coated tool 1 can be extended.

[0032] In this case, as shown in an example in FIG. 3, a plurality of second crystal grains 20b may be located between a plurality of first crystal grains 20a. In such a case, even if a crack propagates in one of the plurality of first crystal grains 20a, the second crystal grains 20b tend to prevent the crack from further propagating. Therefore, the crack is likely to be prevented from spreading over a wide area of ​​the coating layer 20. As a result, the life of the coated tool 1 can be extended.

[0033] As shown in an example in Fig. 3, at least two of the plurality of second crystal grains 20b may be adjacent to each other. In such a case, the second crystal grains 20b are refined to homogenize the coating layer 20, and the plurality of second crystal grains 20b tend to prevent the cracks from propagating over a wide area of ​​the coating layer 20. As a result, the life of the coated tool 1 can be extended.

[0034] Here, a more specific configuration of the coating layer 20 will be described, which includes crystal grains 20a having a plurality of regions with mutually different crystal orientations, has the D2 / D1 value of 0.55 to 0.95, and has a proportion of crystal grains showing the average KAM value of 1 or more of 50% to 80%. That is, the configuration of the coating layer 20A according to the first embodiment and the configuration of the coating layer 20B according to the second embodiment will be described, which are used to realize the coating layer 20 including crystal grains 20a having a plurality of regions with mutually different crystal orientations.

[0035] (Coating layer 20A according to the first embodiment) Here, a specific configuration of the coating layer 20A according to the first embodiment will be described with reference to FIGS. 4, 5A, 5B, 6A, 6B, and 6C. FIG. 4 is a cross-sectional view showing an example of the coating layer according to the first embodiment. FIG. 5A is a schematic view illustrating the Ti / Al ratio in the coating layer according to the first embodiment. FIG. 5B is a schematic view illustrating the Cr / Al ratio in the coating layer according to the first embodiment. FIG. 6A is a cross-sectional view showing an example of a first coating layer included in the coating layer according to the first embodiment. FIG. 6B is a cross-sectional view showing an example of a second coating layer included in the coating layer according to the first embodiment. FIG. 6C is a cross-sectional view showing an example of a third coating layer included in the coating layer according to the first embodiment.

[0036] As shown in Fig. 4, the coating layer 20A according to the first embodiment as the coating layer 20 includes a first coating layer 21 located on the base 10, a second coating layer 22 located on the first coating layer 21, and a third coating layer 23 located on the second coating layer 22. When the chip body 2 includes an intermediate layer 11 in addition to the base 10 and the coating layer 20A as the coating layer 20, the intermediate layer 11 is located between the base 10 and the first coating layer 21 as shown in Fig. 4. In this case, the first coating layer 21 is located on the base 10 via the intermediate layer 11.

[0037] (First covering layer 21) The first coating layer 21 contains Al, Ti, Cr, and N. The first coating layer 21 may be, for example, an AlTiCrN layer containing AlTiCrN, which is a nitride of Al, Ti, and Cr. The term "AlTiCrN" means that Al, Ti, Cr, and N are present in any ratio, and does not necessarily mean that Al, Ti, Cr, and N are present in a 1:1:1:1:1 ratio. The thickness of the first coating layer 21 is, for example, 500 nm or more and 1500 nm or less.

[0038] The first coating layer 21 located on the substrate 10 can reduce the residual stress between the substrate 10 and the coating layers located on the first coating layer 21 (the second coating layer 22 and the third coating layer 23 in the coating layer 20A). That is, the first coating layer 21 can reduce the residual stress between the substrate 10 and the coating layer 20A. This can reduce peeling or cracks between the substrate 10 and the coating layer 20A. In other words, the adhesion between the substrate 10 and the coating layer 20A can be improved. As a result, the life of the coated tool 1 can be extended.

[0039] (Second coating layer 22) As shown in FIG. 4, the second coating layer 22 includes a first film 31 and a second film 32. The first film 31 and the second film 32 each contain Al, Ti, Cr, and N. The first film 31 and the second film 32 may each be, for example, an AlTiCrN film containing AlTiCrN, which is a nitride of Al, Ti, and Cr. The thickness of the first film 31 is, for example, not less than 200 nm and not more than 400 nm. The thickness of the second film 32 is, for example, not less than 200 nm and not more than 400 nm.

[0040] The first film 31 has a higher Ti / Al ratio than the Ti / Al ratio in the first coating layer 21. Here, the Ti / Al ratio means the ratio of the number of Ti atoms to the number of Al atoms. This improves the wear resistance and chipping resistance of the coating layer 20A without significantly increasing the residual stress between the substrate 10 and the coating layer located above the second coating layer 22 (the third coating layer 23 in the coating layer 20A). The first film 31 may have a lower Cr / Al ratio than the Cr / Al ratio in the first coating layer 21.

[0041] The second film 32 has a higher Cr / Al ratio than the Cr / Al ratio in the first coating layer 21. Here, the Cr / Al ratio refers to the ratio of the number of Cr atoms to the number of Al atoms. This improves the lubricity and adhesion resistance of the coating layer 20A without significantly increasing the residual stress between the substrate 10 and the coating layer located above the second coating layer 22 (the third coating layer 23 in the coating layer 20A). The second film 32 may have a lower Ti / Al ratio than the Ti / Al ratio in the first coating layer 21.

[0042] The second coating layer 22 can improve the wear resistance and chipping resistance of the coating layer 20A, as well as the lubricity and adhesion resistance of the coating layer 20A, without significantly increasing the residual stress between the substrate 10 and the coating layer located above the second coating layer 22. As a result, the life of the coated tool 1 can be extended.

[0043] (Third coating layer 23) As shown in FIG. 4, the third coating layer 23 includes a third film 33 and a fourth film 34. The third film 33 and the fourth film 34 each contain Al, Ti, Cr, and N. The third film 33 and the fourth film 34 may each be, for example, an AlTiCrN film containing AlTiCrN, which is a nitride of Al, Ti, and Cr. The thickness of the third film 33 is, for example, not less than 200 nm and not more than 400 nm. The thickness of the fourth film 34 is, for example, not less than 200 nm and not more than 400 nm.

[0044] The third film 33 has a higher Ti / Al ratio than the first film 31. Here, the Ti / Al ratio means the ratio of the number of Ti atoms to the number of Al atoms. This can improve the wear resistance and chipping resistance of the coating layer 20A. The third film 33 may have a lower Cr / Al ratio than the first film 31.

[0045] The fourth film 34 has a higher Cr / Al ratio than the second film 32. Here, the Cr / Al ratio refers to the ratio of the number of Cr atoms to the number of Al atoms. This can improve the lubricity and adhesion resistance of the coating layer 20A. The fourth film 34 may have a lower Ti / Al ratio than the second film 32.

[0046] The third coating layer 23 can improve the wear resistance and chipping resistance of the coating layer 20A, as well as the lubricity and adhesion resistance of the coating layer 20A, thereby extending the life of the coated tool 1.

[0047] (Example of Ti / Al ratio in coating layer 20A) 5A, the Ti / Al ratio in the coating layer 20A may vary continuously in the thickness direction of the coating layer 20A. When the Ti / Al ratio in a target region of the coating layer 20A is not constant, the average value of the Ti / Al ratio in this region may be used as the Ti / Al ratio in this region.

[0048] 5A, the Ti / Al ratio in the coating layer 20A is almost constant in the first coating layer 21. The Ti / Al ratio in the coating layer 20A is maximum in the first film 31 included in the second coating layer 22 and the third film 33 included in the third coating layer 23. The Ti / Al ratio in the coating layer 20A is minimum in the second film 32 included in the second coating layer 22 and the fourth film 34 included in the third coating layer 23.

[0049] Here, not only may the Ti / Al ratio in the first film 31 be larger than the Ti / Al ratio in the first coating layer 21, but also the maximum value of the Ti / Al ratio in the first film 31 may be larger than the Ti / Al ratio in the first coating layer 21. Not only may the Ti / Al ratio in the third film 33 be larger than the Ti / Al ratio in the first film 31, but also the maximum value of the Ti / Al ratio in the third film 33 may be larger than the maximum value of the Ti / Al ratio in the first film 31.

[0050] Not only may the Ti / Al ratio in the second film 32 be smaller than the Ti / Al ratio in the first coating layer 21, but also the minimum value of the Ti / Al ratio in the second film 32 may be smaller than the Ti / Al ratio in the first coating layer 21. Not only may the Ti / Al ratio in the fourth film 34 be smaller than the Ti / Al ratio in the second film 32, but also the minimum value of the Ti / Al ratio in the fourth film 34 may be smaller than the minimum value of the Ti / Al ratio in the second film 32.

[0051] (Example of Cr / Al ratio in coating layer 20A) 5B, the Cr / Al ratio in the coating layer 20A may vary continuously in the thickness direction of the coating layer 20A. When the Cr / Al ratio in a target region of the coating layer 20A is not constant, the average value of the Cr / Al ratio in this region may be used as the Cr / Al ratio in this region.

[0052] 5B, the Cr / Al ratio in the coating layer 20A is almost constant in the first coating layer 21. The Cr / Al ratio in the coating layer 20A is maximum in the second film 32 included in the second coating layer 22 and the fourth film 34 included in the third coating layer 23. The Cr / Al ratio in the coating layer 20A is minimum in the first film 31 included in the second coating layer 22 and the third film 33 included in the third coating layer 23.

[0053] Here, not only may the Cr / Al ratio in the second film 32 be larger than the Cr / Al ratio in the first coating layer 21, but also the maximum value of the Cr / Al ratio in the second film 32 may be larger than the Cr / Al ratio in the first coating layer 21. Not only may the Cr / Al ratio in the fourth film 34 be larger than the Cr / Al ratio in the second film 32, but also the maximum value of the Cr / Al ratio in the fourth film 34 may be larger than the maximum value of the Cr / Al ratio in the second film 32.

[0054] Not only may the Cr / Al ratio in the first film 31 be smaller than the Cr / Al ratio in the first coating layer 21, but also the minimum value of the Cr / Al ratio in the first film 31 may be smaller than the Cr / Al ratio in the first coating layer 21. Not only may the Cr / Al ratio in the third film 33 be smaller than the Cr / Al ratio in the first film 31, but also the minimum value of the Cr / Al ratio in the third film 33 may be smaller than the minimum value of the Cr / Al ratio in the first film 31.

[0055] Although the coating layer 20A is shown in which the first coating layer 21, the first film 31, the second film 32, the third film 33, and the fourth film 34 are laminated in this order on the substrate 10, the first coating layer 21, the second film 32, the first film 31, the fourth film 34, and the third film 33 may also be laminated in this order on the substrate 10.

[0056] (Examples of the first coating layer 21, the second coating layer 22, and the third coating layer 23) 6A, the first coating layer 21 may include a region in which a plurality of compound layers 21a and a plurality of compound layers 21b are alternately stacked. Here, the Ti / Al ratio and the Cr / Al ratio in the compound layer 21a are different from the Ti / Al ratio and the Cr / Al ratio in the compound layer 21b, respectively. For example, the Ti / Al ratio in the compound layer 21a is greater than the Ti / Al ratio in the compound layer 21b, and the Cr / Al ratio in the compound layer 21b is greater than the Cr / Al ratio in the compound layer 21a. The average thickness of each of the compound layers 21a and 21b is 1 nm or more and 10 nm or less.

[0057] In this case, it is possible to improve the hardness of the first coating layer 21. This improves the strength of the first coating layer 21. As a result, it is possible to extend the life of the coated tool 1.

[0058] 6B, the first film 31 included in the second coating layer 22 may include a region in which a plurality of compound layers 31a and a plurality of compound layers 31b are alternately stacked. Here, the Ti / Al ratio and the Cr / Al ratio in the compound layer 31a are different from the Ti / Al ratio and the Cr / Al ratio in the compound layer 31b, respectively. For example, the Ti / Al ratio in the compound layer 31a is greater than the Ti / Al ratio in the compound layer 31b, and the Cr / Al ratio in the compound layer 31b is greater than the Cr / Al ratio in the compound layer 31a. The average thickness of each of the compound layers 31a and 31b is 1 nm or more and 10 nm or less.

[0059] In this case, the hardness of the first film 31 and the hardness of the second coating layer 22 can be improved accordingly. This improves the strength of the first film 31 and the strength of the second coating layer 22 accordingly. As a result, the life of the coated tool 1 can be extended.

[0060] 6B, the second film 32 included in the second coating layer 22 may include a region in which multiple compound layers 32a and multiple compound layers 32b are alternately stacked. Here, the Ti / Al ratio and Cr / Al ratio in the compound layer 32a are different from the Ti / Al ratio and Cr / Al ratio in the compound layer 32b, respectively. For example, the Cr / Al ratio in the compound layer 32a is greater than the Cr / Al ratio in the compound layer 32b, and the Ti / Al ratio in the compound layer 32b is greater than the Ti / Al ratio in the compound layer 32a. The average thickness of each of the compound layers 32a and 32b is 1 nm or greater and 10 nm or less.

[0061] In this case, the hardness of the second film 32 and the hardness of the second coating layer 22 can be improved accordingly. This improves the strength of the second film 32 and the strength of the second coating layer 22 accordingly. As a result, the life of the coated tool 1 can be extended.

[0062] 6C, the third film 33 included in the third coating layer 23 may include a region in which multiple compound layers 33a and multiple compound layers 33b are alternately stacked. Here, the Ti / Al ratio and the Cr / Al ratio in the compound layer 33a are different from the Ti / Al ratio and the Cr / Al ratio in the compound layer 33b, respectively. For example, the Ti / Al ratio in the compound layer 33a is greater than the Ti / Al ratio in the compound layer 33b, and the Cr / Al ratio in the compound layer 33b is greater than the Cr / Al ratio in the compound layer 33a. The average thickness of each of the compound layers 33a and 33b is 1 nm or more and 10 nm or less.

[0063] In this case, it is possible to improve the hardness of the third film 33 and, accordingly, the hardness of the third coating layer 23. This improves the strength of the third film 33 and, accordingly, the strength of the third coating layer 23. As a result, it is possible to extend the life of the coated tool 1.

[0064] 6C, the fourth film 34 included in the third coating layer 23 may include a region in which a plurality of compound layers 34a and a plurality of compound layers 34b are alternately stacked. The Ti / Al ratio and the Cr / Al ratio in the compound layer 34a are different from the Ti / Al ratio and the Cr / Al ratio in the compound layer 34b, respectively. For example, the Cr / Al ratio in the compound layer 34a is greater than the Cr / Al ratio in the compound layer 34b, and the Ti / Al ratio in the compound layer 34b is greater than the Ti / Al ratio in the compound layer 34a. The average thickness of each of the compound layers 34a and 34b is 1 nm or greater and 10 nm or less.

[0065] In this case, it is possible to improve the hardness of the fourth film 34 and, accordingly, the hardness of the third coating layer 23. This improves the strength of the fourth film 34 and, accordingly, the strength of the third coating layer 23. As a result, it is possible to extend the life of the coated tool 1.

[0066] The proportions of elements in the coating layer or film contained in the coating layer 20A can be determined, for example, by analysis based on X-ray photoelectron spectroscopy (XPS) or analysis using an energy dispersive X-ray spectrometer (EDS) attached to a scanning transmission electron microscope (STEM). The presence of multiple compound layers alternately stacked in the film contained in the coating layer 20A can be confirmed by bright-field images or high-angle annular dark-field images obtained by a scanning transmission electron microscope (STEM), or analysis using an energy dispersive X-ray spectrometer (EDS).

[0067] (Middle class 11) 4, an intermediate layer 11 may be located between the base 10 and the coating layer 20A serving as the coating layer 20. Specifically, one surface (here, the lower surface) of the intermediate layer 11 contacts the upper surface of the base 10, and the other surface (here, the upper surface) contacts the lower surface of the coating layer 20A (e.g., the first coating layer 21).

[0068] The intermediate layer 11 has higher adhesion to the substrate 10 than the coating layer 20A. Examples of metal elements having such properties include Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, Si, Y, and Ti. The intermediate layer 11 contains at least one of the above metal elements. For example, the intermediate layer 11 may contain Ti. Si is a metalloid element, and in this specification, metalloid elements are also considered to be included in the metal elements.

[0069] When intermediate layer 11 contains Ti, the Ti content in intermediate layer 11 may be 1.5 atomic % or more. For example, the Ti content in intermediate layer 11 may be 2.0 atomic % or more.

[0070] Intermediate layer 11 may contain components other than the above metal elements (Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, Si, Y, and Ti). However, from the viewpoint of adhesion to substrate 10, intermediate layer 11 may contain the above metal elements in a total amount of at least 95 atomic % or more. Intermediate layer 11 may also contain the above metal elements in a total amount of 98 atomic % or more. The proportion of the metal components in intermediate layer 11 can be determined, for example, by analysis using an energy dispersive X-ray spectrometer (EDS) attached to a scanning transmission electron microscope (STEM).

[0071] In this way, by providing the intermediate layer 11, which has higher wettability with the substrate 10 than the coating layer 20A, between the substrate 10 and the coating layer 20A, it is possible to improve the adhesion between the substrate 10 and the coating layer 20A. Because the intermediate layer 11 also has high adhesion to the coating layer 20A, peeling of the coating layer 20A from the intermediate layer 11 is unlikely to occur.

[0072] The thickness of intermediate layer 11 may be, for example, not less than 0.1 nm and less than 20 nm.

[0073] (Coating layer 20B according to the second embodiment) Next, a specific configuration of a coating layer 20B according to the second embodiment will be described with reference to Fig. 7, Fig. 8A, Fig. 8B, and Fig. 9. Fig. 7 is a cross-sectional view showing an example of a coating layer according to the second embodiment. Fig. 8A is a schematic view illustrating the Ti / Al ratio in the coating layer according to the second embodiment. Fig. 8B is a schematic view illustrating the Cr / Al ratio in the coating layer according to the second embodiment. Fig. 9 is a cross-sectional view showing an example of a fourth coating layer included in the coating layer according to the second embodiment.

[0074] 7, the coating layer 20B according to the second embodiment differs from the coating layer 20A according to the first embodiment in that the coating layer 20B according to the second embodiment further includes a fourth coating layer 24 located on the third coating layer 23. Description of the configuration of the coating layer 20B according to the second embodiment, which is similar to the configuration of the coating layer 20A according to the first embodiment, will be omitted.

[0075] (Fourth coating layer 24) As shown in FIG. 7, the fourth covering layer 24 includes a fifth film 35 and a sixth film 36 .

[0076] The fifth film 35 contains Al, Ti, and N. The fifth film 35 may be, for example, an AlTiN film containing AlTiN, a nitride of Al and Ti. The term "AlTiN" means that Al, Ti, and N are present in any ratio, and does not necessarily mean that Al, Ti, and N are present in a 1:1:1 ratio. The fifth film 35 may further contain Cr. In this case, the fifth film 35 may be, for example, an AlTiCrN film containing AlTiCrN, a nitride of Al, Ti, and Cr. The thickness of the fifth film 35 is, for example, 200 nm or more and 400 nm or less.

[0077] The sixth film 36 contains Al, Cr, and N. The sixth film 36 may be, for example, an AlCrN film containing AlCrN, a nitride of Al and Cr. The term "AlCrN" means that Al, Cr, and N are present in any ratio, and does not necessarily mean that Al, Cr, and N are present in a 1:1:1 ratio. The sixth film 36 may further contain Ti. In this case, the sixth film 36 may be, for example, an AlTiCrN film containing AlTiCrN, a nitride of Al, Ti, and Cr. The thickness of the sixth film 36 is, for example, 200 nm or more and 400 nm or less.

[0078] The fifth film 35 has a higher Ti / Al ratio than the third film 33. Here, the Ti / Al ratio means the ratio of the number of Ti atoms to the number of Al atoms. This can further improve the wear resistance and chipping resistance of the coating layer 20B. The fifth film 35 may have a lower Cr / Al ratio than the third film 33.

[0079] The sixth film 36 has a higher Cr / Al ratio than the fourth film 34. Here, the Cr / Al ratio refers to the ratio of the number of Cr atoms to the number of Al atoms. This can further improve the lubricity and adhesion resistance of the coating layer 20B. The sixth film 36 may have a lower Ti / Al ratio than the fourth film 34.

[0080] The fourth coating layer 24 can further improve the wear resistance and chipping resistance of the coating layer 20B, and can further improve the lubricity and adhesion resistance of the coating layer 20A, thereby further extending the life of the coated tool 1.

[0081] In the coating layer 20B, the third coating layer 23 acts so as not to significantly increase the residual stress between the substrate 10 and the fourth coating layer 24, which is a coating layer located on the third coating layer 23.

[0082] The Ti / Al ratio in the fifth film 35 may be 0.8 or more and 1.2 or less. When the Ti / Al ratio in the fifth film 35 is 0.8 or more, the wear resistance and chipping resistance of the coating layer 20B can be further improved. When the Ti / Al ratio in the fifth film 35 is 1.2 or less, the residual stress between the substrate 10 and the coating layer 20B can be prevented from increasing significantly. This can reduce peeling or cracking between the substrate 10 and the coating layer 20B. As a result, the life of the coated tool 1 can be further extended.

[0083] The Cr / Al ratio in the sixth film 36 may be 0.8 or more and 1.2 or less. When the Cr / Al ratio in the sixth film 36 is 0.8 or more, the lubricity and adhesion resistance of the coating layer 20B can be further improved. When the Cr / Al ratio in the sixth film 36 is 0.8 or more and 1.2 or less, the residual stress between the substrate 10 and the coating layer 20B can be prevented from increasing significantly. This can reduce peeling or cracking between the substrate 10 and the coating layer 20B. As a result, the life of the coated tool 1 can be further extended.

[0084] (Example of Ti / Al ratio in coating layer 20B) 8A, the Ti / Al ratio in the coating layer 20B may vary continuously in the thickness direction of the coating layer 20B. When the Ti / Al ratio in a target region of the coating layer 20B is not constant, the average value of the Ti / Al ratio in this region may be used as the Ti / Al ratio in this region.

[0085] 8A, the Ti / Al ratio in the coating layer 20B is also maximum in the fifth film 35 included in the fourth coating layer 24. The Ti / Al ratio in the coating layer 20B is also minimum in the sixth film 36 included in the fourth coating layer 24.

[0086] Here, the maximum value of the Ti / Al ratio in the fifth film 35 is larger than the maximum value of the Ti / Al ratio in the third film 33. On the other hand, the minimum value of the Ti / Al ratio in the sixth film 36 is smaller than the minimum value of the Ti / Al ratio in the fourth film 34. The minimum value of the Ti / Al ratio in the sixth film 36 is, for example, substantially 0.

[0087] (Example of Cr / Al ratio in coating layer 20B) 8B, the Cr / Al ratio in the coating layer 20B may vary continuously in the thickness direction of the coating layer 20B. When the Cr / Al ratio in a target region of the coating layer 20B is not constant, the average value of the Cr / Al ratio in this region may be used as the Cr / Al ratio in this region.

[0088] 8B, the Cr / Al ratio in the coating layer 20B is also maximum in the sixth film 36 included in the fourth coating layer 24. The Cr / Al ratio in the coating layer 20B is also minimum in the fifth film 35 included in the fourth coating layer 24.

[0089] Here, the maximum value of the Cr / Al ratio in the sixth film 36 is larger than the maximum value of the Cr / Al ratio in the fourth film 34. On the other hand, the minimum value of the Cr / Al ratio in the fifth film 35 is smaller than the minimum value of the Cr / Al ratio in the third film 33. The minimum value of the Cr / Al ratio in the fifth film 35 is, for example, substantially 0.

[0090] Although the coating layer 20B is shown in which the first coating layer 21, the first film 31, the second film 32, the third film 33, the fourth film 34, the fifth film 35, and the sixth film 36 are laminated in this order on the substrate 10, the first coating layer 21, the second film 32, the first film 31, the fourth film 34, the third film 33, the sixth film 36, and the fifth film 35 may also be laminated in this order on the substrate 10.

[0091] (Example of the fourth coating layer 24) 9, the fifth film 35 included in the fourth coating layer 24 may include a region in which multiple compound layers 35a and multiple compound layers 35b are alternately stacked. Here, the Ti / Al ratio in the compound layer 35a is different from the Ti / Al ratio in the compound layer 35b. For example, the Ti / Al ratio in the compound layer 35a is greater than the Ti / Al ratio in the compound layer 35b. The average thickness of each of the compound layers 35a and 35b is 1 nm or more and 10 nm or less.

[0092] In this case, the hardness of the fifth film 35 and, accordingly, the hardness of the fourth coating layer 24 can be improved. In particular, the hardness of the fourth coating layer 24 at high temperatures can be improved. This improves the strength of the fifth film 35 and, accordingly, the strength of the fourth coating layer 24. In particular, the wear resistance of the fourth coating layer 24 can be improved. As a result, the life of the coated tool 1 can be further extended.

[0093] 9, the sixth film 36 included in the fourth coating layer 24 may include a region in which multiple compound layers 36a and multiple compound layers 36b are alternately stacked. Here, the Cr / Al ratio in the compound layer 36a is different from the Cr / Al ratio in the compound layer 36b. For example, the Cr / Al ratio in the compound layer 36a is greater than the Cr / Al ratio in the compound layer 36b. The average thickness of each of the compound layers 36a and 36b is 1 nm or more and 10 nm or less.

[0094] In this case, the hardness of the sixth film 36 and, accordingly, the hardness of the fourth coating layer 24 can be improved. In particular, the hardness of the fourth coating layer 24 at high temperatures can be improved. This improves the strength of the sixth film 36 and, accordingly, the strength of the fourth coating layer 24. In particular, the wear resistance of the fourth coating layer 24 can be improved. As a result, the life of the coated tool 1 can be further extended.

[0095] <Method of manufacturing coated tools> Next, an example of a method for manufacturing the coated tool 1 according to the embodiment will be described with reference to Fig. 10. Fig. 10 is a diagram schematically showing an example of a film-forming apparatus for forming a coating layer on a substrate. The method for manufacturing the coated tool 1 is not limited to the method described below.

[0096] First, a substrate 10 having the shape of the coated tool 1 is prepared using a conventionally known method. Next, a coating layer 20 is formed on the surface of the substrate 10. The coating layer 20 can be formed by, for example, a physical vapor deposition (PVD) method such as an ion plating method or a sputtering method. As an example, when the coating layer 20 is formed by the ion plating method, an arc ion plating film formation apparatus (hereinafter referred to as an AIP apparatus) 1000 as shown in FIG. 10 can be used.

[0097] 10, an AIP apparatus 1000 introduces a gas such as N2 or Ar into a vacuum chamber 101 through a gas inlet 102, and generates a gas plasma by applying a high voltage between a cathode electrode 103 and an anode electrode 104 disposed in the AIP apparatus 1000. This plasma evaporates and ionizes the desired metal or ceramic from a target 105, generating high-energy metal or ceramic ions. This ionized metal or ceramic is then deposited on the surface of a substrate 10 as a sample, thereby forming a coating layer 20 on the surface of the substrate 10.

[0098] As shown in Fig. 10, a plurality of substrates 10 may be set in a tower 107 and placed on a sample support stage 106. A plurality of sample support stages 106 (two sets in the figure) may be placed on a table not shown. Furthermore, as shown in Fig. 10, a heater 108 for heating the substrates 10, a gas outlet 109 for discharging gas out of the system, and a bias power supply 110 for applying a bias voltage to the substrates 10 are provided.

[0099] Examples of target 105 that can be used include metal targets each containing aluminum metal (Al), titanium metal (Ti), and chromium metal (Cr) independently, alloy targets made by combining these, and mixture targets made of powders or sintered bodies of nitrides of these. For example, target 105 can be a first alloy target made by combining Al and Ti, and a second alloy target made by combining Al and Cr.

[0100] Then, using the target 105, the metal source is evaporated by arc discharge or glow discharge, and the metal of the metal source is ionized, and at the same time, the metal is reacted with nitrogen (N2) gas of the nitrogen source, thereby depositing the coating layer 20 on the surface of the substrate 10.

[0101] At this time, the sample support stage 106 is controlled so that the distance from the position of the target 105 to the position of the substrate 10 is 160 mm or more, for example, 260 mm or more. A large number of highly linear magnetic field lines are generated from the center of the surface of the target 105 toward the substrate 10, and the magnetic flux density near the substrate 10 is set to 0.2 to 0.8 mT (millitesla).

[0102] Nitrogen gas may be introduced into the AIP device 1000 as a reactive gas, and the atmospheric pressure may be set to 2 to 10 Pa. The temperature of the substrate 10 is maintained at 300 to 500°C. Furthermore, a bias voltage of -50 to -200 V is applied to the substrate 10, and an arc discharge of 30 to 200 A is generated between the target 105 (cathode electrode 103) and the anode electrode 104. During this time, metal is vapor-deposited onto the substrate 10 while the substrate 10 is rotated and revolved.

[0103] Here, when each coating layer included in the coating layer 20 is laminated on the substrate 10, the current value of the arc discharge generated between the target 105 as the cathode electrode 103 and the anode electrode 104 is controlled. For example, the current value of the arc discharge generated between the anode electrode 104 and the first alloy target as the cathode electrode 103, which is a composite of Al and Ti, or the second alloy target as the cathode electrode 103, which is a composite of Al and Cr, is controlled.

[0104] For example, in order to increase (or decrease) the Ti / Al ratio in the coating layer or film contained in the coating layer 20, the current value of the arc discharge generated between the anode electrode 104 and the first alloy target formed by combining Al and Ti as the cathode electrode 103 is increased (or decreased).

[0105] For example, to increase (or decrease) the Cr / Al ratio in the coating layer or film contained in the coating layer 20, the current value of the arc discharge generated between the second alloy target, which is a composite of Al and Cr and serves as the cathode electrode 103, and the anode electrode 104 is increased (or decreased).

[0106] The magnetic flux density near the substrate 10 can be controlled, for example, by placing an electromagnetic coil or permanent magnet, which is a magnetic field generating source, around the target 105, by placing a permanent magnet inside the AIP device 1000, for example, in the center, or by adjusting the position of an adjacent target 105.

[0107] The magnetic force is calculated by measuring the magnetic flux density at the position of the substrate 10 using a magnetic flux density meter. The magnetic flux density is expressed in units of mT (millitesla). Here, the distance from the position of the target 105 to the position of the substrate 10 represents the distance measured at the position where the substrate 10 is closest to the target 105 and the distance where the substrate 10 is farthest from the target 105.

[0108] During film formation, when the rotation speed of the sample is defined as the period in which the substrate 10 approaches the target 105 most closely at each position on the substrate 10 as shown in Fig. 10, adjusting the rotation speed can adjust the period of the difference in composition between heavy metals and light metals in the thickness direction of the coating layer 20. Specifically, the rotation speed of the substrate 10 and the sample support 106 may be adjusted so that the period is 2 to 20 rpm (revolutions per minute).

[0109] During film formation, the tower 107 may rotate while the sample support stages 106 on which the substrates 10 are placed each rotate, and the table may be rotated so that the plurality of sample support stages 106 revolve. By adjusting the timing of such revolutions, it is possible to control the thickness of each of the compound layers constituting the first coating layer 21, the second coating layer 22 (first film 31 and second film 32), the third coating layer 23 (third film 33 and fourth film 34), and the fourth coating layer 24 (fifth film 35 and sixth film 36).

[0110] By applying a pulsed bias voltage, it is possible to adjust the time or distance that metal ions travel from the target 105 to the substrate 10. This makes it possible to differentiate the composition of heavy metal components and light metal components during film formation.

[0111] For example, when the base 10 is positioned so that it is close to and facing the target 105, heavy metal components from the target 105 fly toward the base 10 in a straight line, and more heavy metals than light metals are deposited on the base 10. On the other hand, when the base 10 is positioned so that it is far from and not facing the target 105, the light metal components wrap around and deposit on the base 10, and it is thought that the amount of deposition of heavy metal components will decrease. In this case, by increasing the distance from the position of the target 105 to the position of the base 10 and maintaining a certain level of magnetic flux density near the base 10, it is thought that the wraparound of the light metal components will be promoted and the composition difference between the heavy metal components and the light metal components will increase.

[0112] <Cutting tools> Next, the configuration of a cutting tool including the above-described coated tool 1 will be described with reference to Fig. 11. Fig. 11 is a front view showing an example of a cutting tool according to an embodiment.

[0113] As shown in FIG. 11, a cutting tool 100 according to the embodiment includes a coated tool 1 and a holder 70 for fixing the coated tool 1.

[0114] The holder 70 is a rod-shaped member extending from a first end (the upper end in FIG. 11) to a second end (the lower end in FIG. 11). The holder 70 is made of, for example, steel or cast iron. Among these materials, steel, which has particularly high toughness, may be used.

[0115] The holder 70 has a pocket 73 at the end on the first end side. The pocket 73 is a portion where the coated tool 1 is attached, and has a seating surface that intersects with the rotation direction of the workpiece and a constraint side surface that is inclined relative to the seating surface. The seating surface is provided with a screw hole into which a screw 75, which will be described later, is threaded.

[0116] The coated tool 1 is positioned in a pocket 73 of the holder 70 and attached to the holder 70 by a screw 75. That is, the screw 75 is inserted into the through hole 5 of the coated tool 1, and the tip of the screw 75 is inserted into a threaded hole formed in the seating surface of the pocket 73 to screw the threaded portions together. In this way, the coated tool 1 is attached to the holder 70 so that the cutting edge portion 3 protrudes outward from the holder 70.

[0117] In the embodiment, a cutting tool used for so-called turning is exemplified. Examples of turning include internal diameter machining, external diameter machining, and grooving. The cutting tool is not limited to that used for turning. For example, the coated tool 1 may be used as a cutting tool used for milling. Examples of cutting tools used for milling include milling cutters such as flat milling cutters, face milling cutters, side milling cutters, and groove milling cutters, and end mills such as single-flute end mills, multi-flute end mills, tapered-flute end mills, and ball end mills. [Example]

[0118] Examples of the present disclosure will be specifically described below, but the present disclosure is not limited to the examples shown below.

[0119] A coated tool according to the example was fabricated by forming a coating layer on a substrate made of a WC-based cemented carbide using an AIP device such as that shown in Figure 10. A first alloy target made of a composite of Al and Ti and a second alloy target made of a composite of Al and Cr were used as targets. Metal ions generated from the first alloy target or the second alloy target were reacted with nitrogen gas to deposit a coating layer on the substrate.

[0120] Here, when the substrate was rotated and revolved and a coating layer was laminated on the substrate, the current value of the arc discharge generated between the first alloy target or the second alloy target as a cathode electrode and the anode electrode was controlled as follows.

[0121] First, the current value of the arc discharge generated between the first alloy target and the anode electrode was set to 190 to 210 A, and the current value of the arc discharge generated between the second alloy target and the anode electrode was set to 190 to 210 A, thereby laminating a first coating layer on the substrate.

[0122] Next, the current value of the arc discharge generated between the first alloy target and the anode electrode was set to 90 to 110 A, and the current value of the arc discharge generated between the second alloy target and the anode electrode was set to 40 to 60 A, thereby laminating the first film contained in the second coating layer on the first coating layer.

[0123] Next, the current value of the arc discharge generated between the first alloy target and the anode electrode was set to 40 to 60 A, and the current value of the arc discharge generated between the second alloy target and the anode electrode was set to 90 to 110 A, thereby laminating a second film included in the second coating layer on the first film.

[0124] Next, the current value of the arc discharge generated between the first alloy target and the anode electrode was set to 110 to 130 A, and the current value of the arc discharge generated between the second alloy target and the anode electrode was set to 20 to 40 A, thereby laminating a third film included in the third coating layer on the second film.

[0125] Next, the current value of the arc discharge generated between the first alloy target and the anode electrode was set to 20 to 40 A, and the current value of the arc discharge generated between the second alloy target and the anode electrode was set to 110 to 130 A, thereby laminating a fourth film included in the third coating layer on the third film.

[0126] Next, the current value of the arc discharge generated between the first alloy target and the anode electrode was set to 140 to 160 A, and the current value of the arc discharge generated between the second alloy target and the anode electrode was set to 0 to 10 A, thereby laminating a fifth film included in the fourth coating layer on the fourth film.

[0127] Finally, the current value of the arc discharge generated between the first alloy target and the anode electrode was set to 0 to 10 A, and the current value of the arc discharge generated between the second alloy target and the anode electrode was set to 140 to 160 A, thereby laminating a sixth film included in the third coating layer on the fifth film.

[0128] The coated tools thus produced were analyzed by X-ray photoelectron spectroscopy (XPS) for the elements contained in the coating layer or film deposited on the substrate.

[0129] It was confirmed that the first coating layer, the first film and the second film included in the second coating layer, and the third film and the fourth film included in the third coating layer each contain Al, Ti, Cr, and N. It was confirmed that the fifth film included in the fourth coating layer contains Al, Ti, and N. It was confirmed that the sixth film included in the fourth coating layer contains Al, Cr, and N.

[0130] It was confirmed that the Ti / Al ratio in the first coating layer, first film, second film, third film, fourth film, fifth film, and sixth film changes continuously with distance from the surface of the substrate in the thickness direction of the coating layer or film, i.e., in the direction perpendicular to the surface of the substrate. It was confirmed that the Cr / Al ratio in the first coating layer, first film, second film, third film, fourth film, fifth film, and sixth film changes continuously with distance from the surface of the substrate in the thickness direction of the coating layer or film, i.e., in the direction perpendicular to the surface of the substrate.

[0131] It was confirmed that the Ti / Al ratio (maximum value 0.8) in the first film was higher than the Ti / Al ratio (0.6) in the first coating layer. It was confirmed that the Cr / Al ratio (maximum value 0.8) in the second film was higher than the Cr / Al ratio (0.6) in the first coating layer. It was confirmed that the Ti / Al ratio (maximum value 1) in the third film was higher than the Ti / Al ratio (maximum value 0.8) in the first film. It was confirmed that the Cr / Al ratio (maximum value 1) in the fourth film was higher than the Cr / Al ratio (maximum value 0.8) in the second film. It was confirmed that the Ti / Al ratio (maximum value 1.4) in the fifth film was higher than the Ti / Al ratio (maximum value 1) in the third film. It was confirmed that the Cr / Al ratio (maximum value 1.2) in the sixth film was higher than the Cr / Al ratio (maximum value 1) in the fourth film.

[0132] The fifth and sixth films were subjected to elemental analysis using an energy dispersive X-ray spectrometer (EDS). Bright-field images and high-angle annular dark-field images were obtained using a scanning transmission electron microscope (STEM).

[0133] It was confirmed that the fifth film included a region in which a plurality of first compound layers and a plurality of second compound layers were alternately stacked, and that the sixth film included a region in which a plurality of third compound layers and a plurality of fourth compound layers were alternately stacked. It was confirmed that the Ti / Al ratio in the first compound layer was different from the Ti / Al ratio in the second compound layer, and that the Cr / Al ratio in the third compound layer was different from the Cr / Al ratio in the fourth compound layer.

[0134] A grain map and an inverse pole figure orientation map for the coating layer (fourth coating layer) were obtained by TEM electron diffraction mapping. Analysis of these maps confirmed that the coating layer contained a plurality of grains, and that the plurality of grains contained grains with regions with continuously varying crystal orientations within the coating layer. It was confirmed that the plurality of grains contained regions with continuously varying crystal orientations.

[0135] Using TEM electron diffraction mapping, misorientations of 5° or more were analyzed as grain boundaries. Furthermore, grain maps were created for cases where the Σ3CSL (correspondence grain boundary) was not considered a grain boundary, and cases where the Σ3CSL (correspondence grain boundary) was considered a grain boundary. The average grain sizes D1 and D2 on each grain map were then calculated as a weighted average based on the area ratio on the grain map, and the D2 / D1 value was confirmed to be between 0.55 and 0.95. Furthermore, using the above grain map data and a crystal orientation analysis system, the average KAM (local misorientation) value for each grain was output, confirming that the proportion of grains with an average KAM value of 1 or greater was between 50% and 80%.

[0136] Adjacent pixels with an orientation difference of 5° or more from the pixel at the center of measurement were excluded from the calculation of the KAM value, as they were considered to have crossed the grain boundary from the single crystal where the pixel at the center of measurement was located. The sample used for the analysis was a thin slice of the coating layer cut in a direction approximately parallel to the surface of the substrate using the FIB method (μ-sampling method). The analysis was performed using the following equipment and conditions.

[0137] TEM electron diffraction mapping method Transmission electron microscope: JEOL JEM-ARM200F Crystal orientation analysis system: NanoMegas ASTAR Measurement conditions: Accelerating voltage: 200 kV Measurement area: 2μm x 2μm Measurement STEP: 10nm

[0138] <Cutting test> Cutting tests were conducted on the coated tools according to the examples and conventional products (Conventional Products 1 and 2) as comparative examples. The test conditions for the cutting tests were as follows: A carbide material for drilling (model number: 2ZDK060-HP-OH (internal coolant type) φ6 mm) was used as the substrate, and the cutting tests were conducted under the following conditions. (1) Cutting method: Drilling (2) Workpiece: SUS304 (3) Cutting speed Vc: 80m / min (4) Feed per revolution f: 0.07 mm / rev (5) Axial cutting depth H: 12 mm (6) Processing form: Wet (7) Evaluation method: Drilling was performed on the substrate under the above conditions, and the maximum wear amount (mm) of the cutting edge of the coated tool after forming 1232 holes in the workpiece was measured. The maximum wear amount of the cutting edge was defined as the maximum value of the depth from the surface of the flank face of the cutting edge to the part where wear was observed.

[0139] Table 1 shows the maximum wear amount of the cutting edges of the coated tools according to the embodiment and the conventional coated tools (Conventional Products 1 and 2) relative to the number of holes formed in the workpiece.

[0140] [Table 1]

[0141] As shown in Table 1, the maximum wear amount of the cutting edge of the coated tool according to the example relative to the number of holes formed in the workpiece is smaller than the maximum wear amount of the cutting edge of the coated tool according to the conventional products (Conventional Products 1 and 2) relative to the same number of holes formed in the workpiece. Therefore, when the coated tool according to the example is compared with the coated tool according to the conventional products (Conventional Products 1 and 2), it was confirmed that the wear resistance of the coated tool according to the example can be improved.

[0142] For the coated tool of Conventional Product 2, significant chipping occurred at the corners of the coated tool when the number of holes reached 1,232. On the other hand, for the coated tool of the Example, no significant chipping occurred. Therefore, it was confirmed that the chipping resistance of the coated tool of the Example can be maintained.

[0143] As described above, the coated tool according to the embodiment (for example, the coated tool 1) includes a substrate (for example, the substrate 10) and a coating layer (for example, the coating layer 20) located on the substrate. The coating layer includes a plurality of crystal grains (for example, crystal grains 20a, 20b). The plurality of crystal grains includes a crystal grain (for example, the crystal grain 20a) having a plurality of regions with different crystal orientations. The crystal orientation of multiple crystal grains in the coating layer is analyzed from the planar direction of the coating layer using TEM electron diffraction mapping, and a first crystal grain map is created from the area where the orientation difference between adjacent measurement points is 5° or more, excluding the Σ3CSL (correspondence grain boundary), with the area being the crystal grain boundary.The average grain size of the crystal grains obtained by taking a weighted average based on the area ratio from the first crystal grain map is defined as D1.A second crystal grain map is created from the area where the orientation difference between adjacent measurement points is 5° or more and the Σ3CSL (correspondence grain boundary), with the area boundary being the crystal grain boundary.The average grain size of the crystal grains obtained by taking a weighted average based on the area ratio from the second crystal grain map is defined as D2.The value of D2 / D1 is 0.55 to 0.95.

[0144] Therefore, the coated tool according to the embodiment can extend the life of the tool.

[0145] 1 is merely an example and does not limit the shape of the coated tool according to the present disclosure. A coated tool according to the present disclosure may 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.

[0146] <Additional Notes> Note (1): a substrate; a coating layer overlying the substrate; Equipped with the coating layer includes a plurality of crystal grains, the plurality of crystal grains includes crystal grains having a plurality of regions with different crystal orientations; analyzing the crystal orientation of the plurality of crystal grains in the coating layer from a planar direction of the coating layer using a TEM electron diffraction mapping method; A first grain map is created by excluding the Σ3CSL (coincidence grain boundary) from the region where the misorientation between adjacent measurement points is 5° or more, and using this region as the grain boundary. The average grain size of the grains obtained by taking a weighted average based on the area ratio from the first grain map is defined as D1. A second grain map is created using the region where the misorientation between the adjacent measurement points is 5° or more and the Σ3CSL (coincidence grain boundary) as grain boundaries, and the average grain size of the grains obtained by taking a weighted average based on the area ratio from the second grain map is defined as D2. The value of D2 / D1 is 0.55 to 0.95. Coated tools. Note (2): The crystal orientations of the plurality of crystal grains in the coating layer are analyzed from the planar direction of the coating layer using a TEM electron diffraction mapping method, and when the region where the orientation difference between the adjacent measurement points is 5° or more and the Σ3CSL (coincidence grain boundary) are defined as crystal grain boundaries, When calculating the average KAM value for each grain in the local misorientation map (KAM map) measured by a crystal orientation analyzer, The proportion of crystal grains showing an average KAM value of 1 or more is 50% or more and 80% or less, 1. The coated tool according to claim 1. Note (3): the plurality of crystal grains comprises a composite nitride; A coated tool according to appendix (1) or (2). Note (4): The plurality of crystal grains are a plurality of first crystal grains having a plurality of regions with different crystal orientations; A plurality of second crystal grains having a certain crystal orientation. Including, The plurality of first crystal grains are located apart from each other. A coated tool according to any one of appendices (1) to (3). Note (5): The second crystal grains are located between the first crystal grains. A coated tool according to appendix (4). Note (6): At least two of the plurality of second crystal grains are adjacent to each other. A coated tool according to appendix (4) or (5). Note (7): a rod-shaped holder having a pocket at an end; The coated tool according to any one of appendices (1) to (6), which is located in the pocket. A cutting tool having

[0147] Further advantages and / or modifications may readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Explanation of symbols]

[0148] 1 Coated tools 2 Chip body 3 Cutting edge 5 through holes 10 Base 11 Middle Class 20, 20A, 20B coating layer 20a, 20b grain 21 First coating layer 22 Second coating layer 23 Third coating layer 24 Fourth coating layer 31 First membrane 32 Second membrane 33 Third Membrane 34 Fourth Membrane 35 Fifth Film 36 Sixth Film 21a, 21b, 31a, 31b, 32a, 32b, 33a, 33b, 34a, 34b, 35a, 35b, 36a, 36b Compound layer 70 Holder 73 Pocket 75 screws 100 cutting tools 101 Vacuum Chamber 102 Gas inlet 103 Cathode electrode 104 Anode electrode 105 Target 106 Sample support 107 Tower 108 Heater 109 Gas outlet 110 Bias power supply 1000 AIP devices

Claims

1. a substrate; a coating layer overlying the substrate; Equipped with the coating layer includes a plurality of crystal grains, the plurality of crystal grains includes crystal grains having a plurality of regions with different crystal orientations; analyzing the crystal orientations of the plurality of crystal grains in the coating layer from a planar direction of the coating layer using a TEM electron diffraction mapping method; A first crystal grain map is created by excluding the Σ3CSL (coincidence grain boundary) from a region where the misorientation between adjacent measurement points is 5° or more, and defining the region as a crystal grain boundary. An average grain size of the crystal grains obtained by taking a weighted average based on the area ratio from the first crystal grain map is defined as D1. A second crystal grain map is created using the region where the orientation difference between the adjacent measurement points is 5° or more and the Σ3CSL (corresponding grain boundary) as crystal grain boundaries, and the average grain size of the crystal grains obtained by taking a weighted average based on the area ratio from the second crystal grain map is defined as D2. The value of D2 / D1 is 0.55 to 0.

95. Coated tools.

2. The crystal orientations of the plurality of crystal grains in the coating layer are analyzed from the planar direction of the coating layer using a TEM electron diffraction mapping method, and when the region where the orientation difference between the adjacent measurement points is 5° or more and the Σ3CSL (corresponding grain boundary) are defined as crystal grain boundaries, When the average KAM value for each crystal grain was calculated in a local misorientation map (KAM map) measured by a crystal orientation analyzer, The proportion of crystal grains having an average KAM value of 1 or more is 50% or more and 80% or less. The coated tool according to claim 1 .

3. the plurality of crystal grains comprises a composite nitride; The coated tool according to claim 1 .

4. The plurality of crystal grains are a plurality of first crystal grains having a plurality of regions with different crystal orientations; a plurality of second crystal grains having a certain crystal orientation; Including, The plurality of first crystal grains are located apart from each other. The coated tool according to claim 1 .

5. The plurality of second crystal grains are located between the plurality of first crystal grains. The coated tool according to claim 4.

6. At least two of the plurality of second crystal grains are adjacent to each other. The coated tool according to claim 4.

7. a rod-shaped holder having a pocket at an end; The coated tool according to any one of claims 1 to 6, which is located in the pocket. A cutting tool having

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