Cermet tool and cutting tool

Abstract

A cermet tool is provided with a base. The matrix includes: a hard phase containing Ti; a binder phase containing at least one of Ni and Co; and a solid solution phase containing Ti and W. The hard phase includes a plurality of hard phase particles. In a cross section of the base, the plurality of hard phase particles satisfy the relationship n2 < n1. And n1 represents the number of the plurality of hard phase particles included in the cross section of the matrix. And n2 represents the number of a plurality of hard phase particles included in the cross section of the matrix and satisfying the relationship Rij < D. And D represents the average particle diameter of the plurality of hard phase particles contained in the cross section of the matrix. Rij represents the distance between the i-th hard-phase particle and the j-th hard-phase particle among the plurality of hard-phase particles included in the cross section of the matrix. I and j are natural numbers satisfying the following conditions: i, j < = n1 and i < j or j < i.

Description

Technical Field

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

[0002] For example, Japanese Patent Application Publication No. 2013-010997 discloses a metal ceramic comprising a hard phase of a compound of at least one metallic element selected from Groups 4, 5, and 6 of the periodic table and at least one element selected from carbon and nitrogen, bonded together by a binder phase mainly composed of iron group metals. The hard phase can be classified as: a first hard phase consisting only of titanium carbonitride; a second hard phase consisting of a composite carbonitride solid solution containing at least titanium and tungsten; and a third hard phase consisting of the same elements as the second hard phase, but with a higher tungsten concentration than the second hard phase.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-010997 Summary of the Invention

[0006] A cermet cutting tool disclosed herein comprises a matrix. The matrix includes: a hard phase containing Ti; a binder phase containing at least one of Ni and Co; and a solid solution phase containing Ti and W. The hard phase comprises a plurality of hard phase particles. In a cross-section of the matrix, the plurality of hard phase particles satisfy the relationship n2 < n1. n1 represents the number of the plurality of hard phase particles contained in the cross-section of the matrix. n2 represents the number of the plurality of hard phase particles contained in the cross-section of the matrix satisfying R ij The relationship <D> refers to the number of the plurality of hard phase particles. D represents the average particle size of the plurality of hard phase particles contained in the cross-section of the matrix. R ij This represents the distance between the i-th and j-th hard phase particles among the plurality of hard phase particles contained in the cross-section of the matrix. i and j are natural numbers satisfying the following conditions: i, j ≤ n1 and i < j or j < i. Attached Figure Description

[0007] Figure 1 This is a perspective view showing an example of a metal-ceramic cutting tool according to an embodiment.

[0008] Figure 2 This is a side sectional view illustrating an example of a cermet cutting tool according to an embodiment.

[0009] Figure 3 This is a schematic diagram showing a scanning electron microscope image of a cross-section of the substrate according to the embodiment.

[0010] Figure 4 This describes the D and R of multiple hard phase particles in the implementation method. ij The calculated graph.

[0011] Figure 5 This is a front view showing an example of a cutting tool according to an embodiment.

[0012] Figure 6 These are scanning electron microscope images of a cross-section of the substrate in the embodiment.

[0013] Figure 7 This is an image of multiple hard phase particles extracted from a cross section of the matrix in the embodiment.

[0014] Figure 8 This illustrates R of multiple hard phase particles extracted from a cross-section of the matrix for an embodiment. ij The image of the analysis result.

[0015] Figure 9 These are scanning electron microscope images of the cross-section of the matrix of the comparative example. Detailed Implementation

[0016] Hereinafter, with reference to the accompanying drawings, the embodiments (hereinafter referred to as "Embodiments") for implementing the cermet cutting tools and cutting tools of this disclosure will be described in detail. The cermet cutting tools and cutting tools of this disclosure are not limited to these embodiments. Various embodiments can be appropriately combined without contradicting the intended content. In the following embodiments, the same reference numerals are used to denote the same parts, and repeated descriptions are omitted.

[0017] In the embodiments shown below, expressions such as "certain," "orthogonal," "perpendicular," or "parallel" are sometimes used. These expressions do not necessarily need to strictly represent "certain," "orthogonal," "perpendicular," or "parallel." That is, the above-mentioned expressions allow for deviations, such as manufacturing precision or setting precision.

[0018] There is still room for improvement in terms of wear resistance and chipping resistance in conventional cermet cutting tools.

[0019] Therefore, there is a strong desire for a technology that can overcome the aforementioned problems and improve wear resistance and damage resistance.

[0020] <Metal-Ceramic Cutting Tools>

[0021] Figure 1 This is a perspective view showing an example of a metal-ceramic cutting tool according to an embodiment. Figure 2 This is a side sectional view showing an example of the metal-ceramic cutting tool 1 according to an embodiment.

[0022] like Figure 1 and Figure 2 As shown, the cermet cutting tool 1 of the embodiment includes a substrate 2. The cermet cutting tool 1 of the embodiment may also include a coating layer 3 located on the surface of the substrate 2, in addition to the substrate 2.

[0023] (Matrix 2)

[0024] The substrate 2 has, for example, an upper surface and a lower surface (with) Figure 1 The shape of the surfaces intersecting the Z-axis shown is a parallelogram-shaped hexahedron.

[0025] One corner of the base 2 functions as a cutting edge. The cutting edge includes a first face (e.g., an upper surface) and a second face (e.g., a side surface) connected to the first face. In an embodiment, the first face functions as a "rake face" for scooping up chips generated by cutting, and the second face functions as a "flank face". The cutting edge is located at least a portion of the edge where the first and second faces intersect, and the cermet tool 1 cuts the workpiece by abutting the cutting edge against it.

[0026] A through hole 21 can be provided in the center of the base 2, extending vertically through the base 2. In this case, a screw 75 for mounting the cermet tool 1 to the bracket 70 described later is inserted into the through hole 21 (see reference). Figure 5 ).

[0027] The substrate 2 is made of cermet. The cermet contains Ti (titanium) and W (tungsten), and contains at least one of Co (cobalt) and Ni (nickel).

[0028] Figure 3 This is a schematic diagram showing a scanning electron microscope image of a cross-section of the substrate 2 according to the embodiment. (See figure) Figure 3 As shown, the matrix 2, composed of cermet, includes a hard phase 5, a binder phase 6, and a solid solution phase 7. More specifically, in the matrix 2, the hard phase 5 and the solid solution phase 7 are bonded together by the binder phase 6. The hard phase 5 can be directly bonded together by the binder phase 6. Alternatively, the hard phase 5 can also be indirectly bonded together by the binder phase 6 via the solid solution phase 7.

[0029] The hard phase 5 contains Ti. For example, the hard phase 5 contains at least one of Ti carbides, nitrides, and carbonitrides. For example, the hard phase 5 is mainly composed of TiCN. Here, "main component" means, for example, that the mass of TiCN is 55% by mass or more relative to the total mass of the components constituting the hard phase 5. The metal constituting the hard phase 5 contains, for example, Ti, W, and at least one of Group 4, Group 5, and Group 6 metals other than Ti and W. The content of Ti in the metal constituting the hard phase 5 is 80% by mass or more. The total content of W and at least one of Group 4, Group 5, and Group 6 metals other than W in the metal constituting the hard phase 5 is 1% by mass or more and 15% by mass or less. The hard phase 5 contains at least one of Co and Ni as a remainder. Here, the total content of Ti, W, at least one of Group 4, Group 5, and Group 6 metals other than Ti and W, Co, and Ni in the metal constituting the hard phase 5 is 100% by mass.

[0030] The binder phase 6 contains at least one of Ni and Co. For example, the binder phase 6 contains at least one of Ni and Co and W.

[0031] Solid solution phase 7 contains Ti and W. For example, solid solution phase 7 is a solid solution containing at least one carbide, nitride, and carbonitride of Ti, W, and at least one metal from Groups 4, 5, and 6 of the periodic table other than Ti and W. For example, the metal constituting solid solution phase 7 contains at least one metal from Groups 4, 5, and 6 of the periodic table other than Ti and W, and at least one metal from Ni and Co. The content of Ti in the metal constituting solid solution phase 7 is 30% by mass or more and 70% by mass or less. The total content of W and at least one metal from Groups 4, 5, and 6 of the periodic table other than Ti and W in the metal constituting solid solution phase 7 is 70% by mass or more and 30% by mass or less. The total content of at least one metal from Ni and Co in the metal constituting solid solution phase 7 is 0% by mass or more and 3% by mass or less. Here, the total content of Ti, W, at least one of the metals of Group 4, Group 5 and Group 6 of the periodic table other than Ti and W, and at least one of Ni and Co in the metal constituting the solid solution phase 7 is 100% by mass.

[0032] The hard phase 5 comprises multiple hard phase particles. For example, the hard phase 5 is composed of multiple hard phase particles. In the cross-section of the matrix 2, the multiple hard phase particles satisfy the relationship n2 < n1, where n1 represents the number of multiple hard phase particles contained in the cross-section of the matrix 2, and n2 represents the number of hard phase particles contained in the cross-section of the matrix 2 satisfying R ijThe relationship <D represents the number of multiple hard phase particles, where D represents the average particle size of the multiple hard phase particles contained in the cross section of matrix 2, and R... ij Let represent the distance between the i-th hard phase particle and the j-th hard phase particle among the multiple hard phase particles contained in the cross section of matrix 2, where i and j are natural numbers that satisfy the following conditions: i, j ≤ n1, and i < j or j < i.

[0033] The cross-section of matrix 2 is any cross-section that confirms that multiple hard phase particles satisfy the relationship n2 < n1. The cross-section of matrix 2 is, for example, a reflected electron image of the cross-section taken using a scanning electron microscope (SEM). In the reflected electron image, the hard phase 5 or multiple hard phase particles are observed to be darker than the solid solution phase 7. On the other hand, the binder phase 6 is observed to be whiter than the solid solution phase 7. That is, the solid solution phase 7 is observed to be a grayish-white color between the color of the hard phase 5 or multiple hard phase particles and the color of the binder phase 6. The cross-section of matrix 2 can be, for example, a cross-section with dimensions of 10 μm × 10 μm.

[0034] To identify individual hard phase particles among the multiple hard phase particles constituting hard phase 5 in the cross-section of matrix 2, electron backscatter diffraction (EBSD) of a scanning electron microscope can be used, for example. Specifically, in a scanning electron microscope, electron beams are irradiated onto the cross-section of matrix 2, and the reflected electrons from the cross-section of matrix 2 are received using a fluorescent plate, thereby obtaining a Kikuchi pattern reflecting the crystal structure of each hard phase particle among the multiple hard phase particles. By obtaining information about the crystal orientation of each hard phase particle among the multiple hard phase particles from this pattern, each hard phase particle among the multiple hard phase particles can be identified.

[0035] Here, "in the cross section of matrix 2, multiple hard phase particles satisfy the relationship n2 < n1" means, for example, that at least 95% of the multiple hard phase particles in the cross section of matrix 2 satisfy the relationship n2 < n1.

[0036] When calculating n1 and n2 of the multiple hard phase particles in the cross-section of the matrix 2, a binarization process can be applied by binarizing the reflected electron image of the cross-section taken using a scanning electron microscope. The binarization process can be performed, for example, by coloring the image of the hard phase 5 in the reflected electron image of the cross-section taken using a scanning electron microscope as black, and coloring the images of the binder phase 6 and the solid solution phase 7 as white. When calculating n1 and n2 of the multiple hard phase particles in the cross-section of the matrix 2, an extraction process can be applied to extract a portion of the image of the hard phase 5 in the reflected electron image of the cross-section taken using a scanning electron microscope. In the extraction process, multiple hard phase particles constituting the hard phase 5 in the cross-section taken using a scanning electron microscope whose particle size is above a certain threshold are extracted. For example, in the extraction process, multiple hard phase particles having a particle size within 90% of the maximum particle size in the particle size distribution of the multiple hard phase particles can be extracted.

[0037] n1 represents the number of multiple hard phase particles contained in the cross-section of the matrix 2. For example, n1 is the number of multiple hard phase particles constituting the hard phase 5 in a cross-sectional electron image taken using a scanning electron microscope. For example, n1 is the number of multiple hard phase particles in a processed image obtained by applying at least one of the binarization and extraction processes described above to the cross-sectional electron image taken using a scanning electron microscope.

[0038] n2 represents the cross section of base 2 containing elements satisfying R. ij The number of multiple hard phase particles in the relationship <D. D represents the average particle size of the multiple hard phase particles contained in the cross section of matrix 2. R ij This represents the distance between the i-th and j-th hard phase particles in the cross-section of matrix 2. i and j are natural numbers satisfying the following conditions: i, j ≤ n1 and i < j or j < i. Here, the natural numbers satisfying i, j ≤ n1 and i < j or j < i represent either the natural numbers satisfying i, j ≤ n1 and i < j or the natural numbers satisfying i, j ≤ n1 and j < i. n2 represents the number of combinations of hard phase particles whose distances are smaller than the average particle size of the hard phase particles. Here and below, "combination" does not consider order.

[0039] Figure 4 This describes the D and R of multiple hard phase particles in the implementation method. ij The calculated graph. The D and R values ​​for multiple hard phase particles related to the implementation method were calculated. ijFor example, a processed image can be obtained by applying at least one of the binarization and extraction processes described above to a cross-sectional reflected electron image taken using a scanning electron microscope.

[0040] Regarding D, firstly, as Figure 4 As shown, the particle size Di of the i-th hard phase particle 5i contained in the cross-section of matrix 2 is calculated. Specifically, as... Figure 4 As shown, the diameter Di of the largest circumcircle centered on the center Ci of the i-th hard phase particle 5i contained in the cross-section of matrix 2 is calculated as the particle size Di of the i-th hard phase particle 5i. Next, the average value of the particle size Di of the i-th hard phase particle 5i contained in the cross-section of matrix 2 is calculated for the n1 hard phase particles contained in the cross-section of matrix 2. That is, the sum of the particle sizes Di of the i-th hard phase particle 5i for i=1~n1 is calculated as n1. This calculated value is used as the average particle size D of the multiple hard phase particles contained in the cross-section of matrix 2.

[0041] Regarding R ij ,like Figure 4 As shown, the distance R between the i-th hard phase particle 5i and the j-th hard phase particle 5j contained in the cross section of the matrix 2 is calculated. ij Specifically, such as Figure 4 As shown, the shortest distance between the i-th hard phase particle 5i and the j-th hard phase particle 5j contained in the cross-section of matrix 2 is calculated and taken as the distance Rij between the i-th hard phase particle 5i and the j-th hard phase particle 5j. That is, the distance R between the i-th hard phase particle 5i and the j-th hard phase particle 5j is... ij It is the distance between the point on the i-th hard phase particle 5i that is closest to the j-th hard phase particle 5j and the point on the j-th hard phase particle 5j that is closest to the i-th hard phase particle 5i.

[0042] Determine whether the multiple hard phase particles contained in the cross section of matrix 2 satisfy R ij <D relationship. The j-th hard phase particle 5j satisfies R relative to the i-th hard phase particle 5i. ij In the case of the relationship <D, it is determined that the combination of the i-th hard phase particle 5i and the j-th hard phase particle 5j satisfies R. ij <D relationship. On the other hand, the j-th hard phase particle 5j does not satisfy R relative to the i-th hard phase particle 5i. ij In the case of <D, it is determined that the combination of the i-th hard phase particle 5i and the j-th hard phase particle 5j does not satisfy R. ij The relationship <D. This will be judged as satisfying R. ijThe total number of combinations of the i-th hard phase particle 5i and the j-th hard phase particle 5j with the relationship <D is calculated as n2.

[0043] When multiple hard phase particles satisfy the relationship n2 < n1, the number of combinations of multiple hard phase particles that are adjacent or in contact with each other is smaller relative to the number of multiple hard phase particles contained in the cross-section of the matrix 2. In this case, the multiple hard phase particles are considered to be better dispersed in the cross-section of the matrix 2. Therefore, the propagation of cracks at the interface between multiple hard phase particles that are adjacent or in contact with each other can be reduced or prevented. Correspondingly, the wear resistance and chipping resistance of the matrix 2 can be improved. Thus, the wear resistance and chipping resistance of the cermet cutting tool 1 can be improved.

[0044] Binarization and extraction of cross-sectional reflected electron images obtained using a scanning electron microscope, and D and R values ​​for multiple hard phase particles. ij The calculation of n1 and n2 for multiple hard phase particles can be performed using image processing software. For example, WINROOF 2021 can be used as such image processing software.

[0045] For example, in the cross section of matrix 2, multiple hard phase particles satisfy the relationship n2 < (n1 / 2).

[0046] When multiple hard phase particles satisfy the relationship n2 < (n1 / 2), the number of combinations of hard phase particles that are adjacent or in contact with each other is less than the number of hard phase particles contained in the cross-section of the matrix 2. In this case, the multiple hard phase particles are considered to be better dispersed in the cross-section of the matrix 2. Therefore, it is possible to further reduce or prevent the propagation of cracks at the interface between multiple hard phase particles that are adjacent or in contact with each other. Correspondingly, the wear resistance and chipping resistance of the matrix 2 can be further improved. Thus, the wear resistance and chipping resistance of the cermet cutting tool 1 can be further improved.

[0047] For example, in the cross-section of matrix 2, multiple hard phase particles satisfy R ij The relationship is greater than 0. Here, i and j are any natural numbers that satisfy the following conditions: i, j ≤ n1 and i < j or j < i. "Multiple hard phase particles satisfy R ij "Relationship > 0" means that multiple hard phase particles do not satisfy R ij The relationship is 0, meaning that multiple hard phase particles are separated without contact with each other. In the case of multiple hard phases in contact with each other, these multiple hard phases can be regarded as a whole as a single hard phase particle.

[0048] In multiple hard phase particles satisfy R ijWhen the relationship is greater than 0, the multiple hard phase particles do not contain multiple hard phase particles in contact with each other. Therefore, the propagation of cracks at the interface between multiple hard phase particles in contact with each other can be prevented. Correspondingly, the wear resistance and chipping resistance of the matrix 2 can be further improved. Thus, the wear resistance and chipping resistance of the cermet cutting tool 1 can be further improved.

[0049] The binder phase 6 comprises multiple binder phase particles. For example, the binder phase 6 is composed of multiple binder phase particles. For example, the average particle size D of the multiple hard phase particles contained in the cross section of the matrix 2 is smaller than the average particle size of the multiple binder phase particles contained in the cross section of the matrix 2.

[0050] The average particle size of the multiple binder phase particles contained in the cross-section of matrix 2 can also be calculated in the same way as the average particle size D of the multiple hard phase particles contained in the cross-section of matrix 2. However, the binarization process in calculating the average particle size of the multiple binder phase particles can be performed, for example, by coloring the image of the binder phase 6 in the cross-section reflected electron image taken using a scanning electron microscope as black and coloring the images of the hard phase 5 and the solid solution phase 7 as white. The extraction process in calculating the average particle size of the multiple binder phase particles can be performed, for example, by extracting the multiple binder phase particles having a particle size within 90% of the maximum particle size in the particle size distribution of the multiple binder phase particles. The diameter of the largest circumscribed circle centered on the center of the binder phase particles contained in the cross-section of matrix 2 is calculated as the particle size of the binder phase particles. The average particle size of the multiple binder phase particles contained in the cross-section of matrix 2 is calculated as the average particle size of the multiple binder phase particles.

[0051] When the average particle size D of the multiple hard phase particles contained in the cross section of the matrix 2 is smaller than the average particle size of the multiple binder phase particles contained in the cross section of the matrix 2, it is easier to reduce the number of multiple hard phase particles that are adjacent or in contact with each other. That is, it is easier to disperse the multiple hard phase particles in the cross section of the matrix 2. Therefore, it is easier to reduce or prevent the propagation of cracks at the interface between multiple hard phase particles that are adjacent or in contact with each other. Correspondingly, it is easier to improve the wear resistance and chip resistance of the matrix 2. Therefore, it is easier to improve the wear resistance and chip resistance of the cermet cutting tool 1.

[0052] For example, in the cross section of the matrix 2, multiple hard phase particles are surrounded by the solid solution phase 7 and separated from the binder phase 6. Here, "in the cross section of the matrix 2, multiple hard phase particles are surrounded by the solid solution phase 7 and separated from the binder phase 6" means, for example, that at least 95% of the multiple hard phase particles in the cross section of the matrix 2 are surrounded by the solid solution phase 7 and separated from the binder phase 6.

[0053] When multiple hard phase particles are surrounded by the solid solution phase 7 and separated from the binder phase 6, the difference between the thermal expansion coefficients of the multiple hard phase particles and the solid solution phase 7, as well as the difference between the thermal expansion coefficients of the solid solution phase 7 and the binder phase 6, can be reduced. This improves the bonding force between the multiple hard phase particles and the solid solution phase 7, and the bonding force between the solid solution phase 7 and the binder phase 6. Correspondingly, the wear resistance and chip resistance of the matrix 2 can be further improved. That is, the wear resistance and chip resistance of the cermet cutting tool 1 can be further improved.

[0054] (Coating layer 3)

[0055] The coating layer 3 is applied to the substrate 2 for purposes such as improving the wear resistance and heat resistance of the substrate 2. Figure 2 The diagram shows an example where the coating layer 3 completely covers the surface of the substrate 2, but the coating layer 3 does not necessarily need to cover the entire surface of the substrate 2. The coating layer 3 only needs to be located on at least a portion of the surface of the substrate 2. When the coating layer 3 is located on the first surface of the substrate 2 (here, the upper surface), the first surface has higher wear resistance and heat resistance. When the coating layer 3 is located on the second surface of the substrate 2 (here, the side surface), the second surface has higher wear resistance and heat resistance.

[0056] The coating layer 3 can be composed of, for example, at least one metallic element selected from elements of Groups 4, 5, and 6 of the periodic table, as well as Al (aluminum) and Si (silicon), and at least one non-metallic element selected from C (carbon), N (nitrogen), and O (oxygen). With this structure, the oxidation resistance of the coating layer 3 is improved. Consequently, the wear resistance of the coating layer 3 is further improved. The coating layer 3 can be a single layer. The cermet cutting tool 1 can also have two or more coating layers 3 stacked in layers.

[0057] (Manufacturing method)

[0058] Next, the manufacturing method of the substrate 2 made of the metal ceramic according to the embodiment will be described.

[0059] First, multiple raw material powders are mixed to adjust the mixed powder. Specifically, at least one of the following is used: TiCN powder with an average particle size of 0.1 μm or more and 1.2 μm or less; WC powder with an average particle size of 0.1 μm or more and 2.5 μm or less; Cr3C2 powder with an average particle size of 2 μm or more and 4 μm or less; carbide powders of metals from Groups IV, V, and VI of the periodic table (excluding TiCN, WC, and Cr3C2); nitride powders; and carbonitride powders; as well as metallic W powder and WC powder with an average particle size of 3 μm or more and 15 μm or less. 1-x (0 < x ≤ 1) At least one of the powders is mixed to adjust the mixed powder.

[0060] Here, the average particle size of the TiCN powder can also be above 0.3 μm and below 0.9 μm. The aforementioned metallic W powder and WC... 1-x (0 < x ≤ 1) At least one of the powders may also be 1% by mass or more and 20% by mass or less relative to the total of the mixed powder. Carbon powder may be added to the mixed powder, and a specified amount of MnCO3 powder with an average particle size of 0.5 μm or more and 5 μm or less may also be added.

[0061] In this embodiment, at least one of the carbide powder, nitride powder, and carbonitride powder of group 4, 5, and 6 metals of the periodic table other than TiCN can be used, including TiC powder, TiN powder, WC powder, NbC powder, Mo2C powder, TaC powder, VC powder, or ZrC powder with an average particle size of 0.1 μm or more and 3 μm or less.

[0062] The powder mixture is adjusted by adding organic binders and / or solvents to the raw material powders and mixing them using known mixing methods such as ball mills, vibratory mills, jet mills, and vertical ball mills. When using powder mixing based on a vertical ball mill, the raw material powders are pulverized and the particle size decreases; however, metal powders have high ductility and therefore tend to be difficult to pulverize.

[0063] Next, at least one of metallic Co powder and / or metallic Ni powder, having an average particle size of 0.5 μm or more and 5 μm or less, is added to the prepared mixed powder. After addition, the powder is mixed and dried using the known mixing method described above, thereby preparing the mixed powder.

[0064] The obtained mixed powder is formed into a molded body of a specified shape using known forming methods such as stamping, extrusion, and injection molding.

[0065] Next, the molded article is fired in a vacuum or inert gas atmosphere. In this embodiment, by firing under the following conditions, a metal ceramic with the specified structure described above can be produced.

[0066] (a) The temperature is raised from room temperature to 450°C and maintained at 450°C for more than 0.5 hours and less than 2 hours.

[0067] (b) Further increase the temperature from 450°C to above 1000°C and below 1100°C.

[0068] (c) In a vacuum, the temperature is further increased from a temperature of 1000°C or higher and 1100°C to a firing temperature of 1280°C or higher and 1380°C at a first heating rate of 0.1°C / min or higher and 10°C / min or lower.

[0069] (d) In a vacuum or an inert gas atmosphere of 30 Pa or more and 20000 Pa or less, the temperature is increased from the firing temperature T1 to a firing temperature T2 of 1500°C or more and 1600°C at a second heating rate of 4°C / min or more and 15°C / min or less.

[0070] (e) In a vacuum or an inert gas atmosphere of 30 Pa or more and 20000 Pa or less, the firing temperature T2 is maintained at the firing temperature T2 for 0.5 hours or more and 2 hours or less.

[0071] (f) Cooling is performed in a vacuum or inert gas atmosphere of 30 Pa or higher and 20000 Pa at a cooling rate e of 5 °C / min or higher and 40 °C / min or lower.

[0072] Next, a coating layer 3 can be formed on the substrate 2 as needed. The coating layer 3 can be any so-called rigid film, such as one formed by PVD or CVD. The coating layer 3 can be a single layer or a multilayer film.

[0073] <Cutting Tools>

[0074] Next, refer to Figure 5 The structure of the cutting tool having the above-mentioned metal-ceramic tool 1 will be described. Figure 5 This is a front view showing an example of a cutting tool according to an embodiment.

[0075] like Figure 5 As shown, the cutting tool 100 of the embodiment has a cermet tool 1 and a tool holder 70 for fixing the cermet tool 1.

[0076] The handle 70 is from the front end ( Figure 5 The upper part of the middle faces the rear end ( Figure 5 A rod-shaped component extending from the lower end of the handle. The handle 70 is made of, for example, steel or cast iron. For example, steel with higher toughness among the aforementioned materials is used.

[0077] The tool holder 70 has a groove 73 at its end located on the front end side. The groove 73 is the part for mounting the cermet tool 1, and has a mounting surface intersecting the rotation direction of the workpiece and a constraint side inclined relative to the mounting surface. A threaded hole for screwing into the screw 75, which will be described later, is provided on the mounting surface.

[0078] The cermet cutting tool 1 is located in the groove 73 of the tool holder 70 and is mounted to the tool holder 70 by a screw 75. That is, the screw 75 is inserted into the through hole 21 of the cermet cutting tool 1, and the front end of the screw 75 is inserted into the threaded hole formed in the mounting surface of the groove 73 so that the threads are screwed together. Thus, the cermet cutting tool 1 is mounted to the tool holder 70 such that the cutting edge protrudes outward from the tool holder 70.

[0079] In this embodiment, a cutting tool 100 for so-called turning is illustrated. Turning can include, for example, internal diameter machining, external diameter machining, or grooving. The cutting tool is not limited to those used for turning. For example, a cermet cutting tool 1 can also be used as a cutting tool for milling. Examples of cutting tools for milling include end mills such as face mills, front end mills, side end mills, or grooving end mills, as well as end mills such as single-flute end mills, multi-flute end mills, tapered end mills, or ball end mills.

[0080]

Example

[0081] The embodiments of this disclosure will now be described in detail. This disclosure is not limited to the embodiments shown below.

[0082] The substrate of the embodiment is manufactured according to the method for manufacturing a substrate 2 made of a metal-ceramic material as described above.

[0083] First, a first mixed powder was obtained by mixing 60% by mass of TiCN powder with an average particle size of 1 μm, 10% by mass of WC powder with an average particle size of 1 μm, 6% by mass of NbC powder with an average particle size of 1 μm, and 6% by mass of Mo2C powder with an average particle size of 3 μm using isopropanol (IPA).

[0084] Next, 2% by mass of Cr3C2 powder with an average particle size of 3 μm, 8% by mass of Ni powder with an average particle size of 3 μm, and 8% by mass of metallic Co powder with an average particle size of 3 μm were added to the first mixed powder, and then mixed and dried using IPA to obtain the second mixed powder.

[0085] The obtained second mixed powder is formed into a block shape by stamping. Then, the above-mentioned molded body is fired under the following conditions to obtain the matrix of the embodiment.

[0086] (a) Heat from room temperature to 450°C and maintain at 450°C for 2 hours.

[0087] (b) Further increase the temperature from 450°C to 1100°C.

[0088] (c) In a vacuum, the temperature is further increased from 1100°C to a firing temperature T1 of 1350°C at a first heating rate of 3°C / min.

[0089] (d) In a nitrogen atmosphere with a pressure of 1000 Pa, the firing temperature is increased from the firing temperature T1 to the firing temperature T2 of 1550 °C at a second heating rate of 10 °C / min.

[0090] (e) Maintain the firing temperature at T2 for 1 hour in a nitrogen atmosphere.

[0091] (f) Cooling in an argon atmosphere at a cooling rate e of 10 °C / min.

[0092] Figure 6 These are scanning electron microscope images of a cross-section of the substrate in the embodiment. Figure 7 This is an image of multiple hard phase particles extracted from a cross section of the matrix in the embodiment. Figure 8 This illustrates R of multiple hard phase particles extracted from a cross-section of the matrix for an embodiment. ij The image shows the analytical results. Previous substrates were prepared as comparative examples. Figure 9 These are scanning electron microscope images of the cross-section of the matrix of the comparative example.

[0093] like Figure 6 and Figure 9 As shown, it was confirmed that the matrix of both the embodiment and the comparative example comprised a hard phase shown in black, a binder phase shown in white, and a solid solution phase shown in off-white. It was also confirmed that in both the matrix of the embodiment and the matrix of the comparative example, the hard phase consisted of multiple hard phase particles, and the binder phase consisted of multiple binder phase particles.

[0094] Next, the D and R values ​​of the plurality of hard phase particles contained in the hard phase of the matrix constituting the embodiment are calculated. ij n1, n2. For example Figure 6 The reflected electron image of the matrix cross-section shown in the embodiment is subjected to binarization processing to emphasize multiple hard phase particles, and extraction processing to extract multiple hard phase particles with a particle size within 90% of the maximum particle size in the particle size distribution. Thus, an extraction process is obtained. Figure 7 An image showing multiple extracted hard phase particles, as shown. Figure 7 The image shown was processed using image processing software (WINROOF 2021) to calculate the D and R values ​​for multiple hard phase particles. ij n1, n2. For example, calculate Figure 8 The R of the extracted multiple hard phase particles as shown in the figure ij Here, D and n1 are 0.2573 μm and 241, respectively. Based on the calculated D and R... ij The calculated n² is 95.

[0095] On the other hand, D and R were also calculated in the same manner for the multiple hard phase particles constituting the hard phase contained in the matrix of the comparative example. ij n1, n2. Here, D and n1 are 0.3941 μm and 385, respectively. Based on the calculated D and R... ij The calculated n² is 844.

[0096] In the matrix of the embodiment, it was confirmed that in the cross-section of the matrix, multiple hard phase particles satisfy the relationship n2 < n1. On the other hand, in the matrix of the comparative example, it was confirmed that in the cross-section of the matrix, multiple hard phase particles do not satisfy the relationship n2 < n1.

[0097] In the matrix of the embodiment, it was confirmed that in the cross-section of the matrix, the multiple hard phase particles satisfy the relationship n2 < (n1 / 2). On the other hand, in the matrix of the comparative example, it was confirmed that in the cross-section of the matrix, the multiple hard phase particles do not satisfy the relationship n2 < (n1 / 2).

[0098] In the matrix of the embodiment, it was confirmed that in the cross-section of the matrix, multiple hard phase particles satisfy R ij The relationship is greater than 0. On the other hand, in the matrix of the comparative example, it was confirmed that multiple hard phase particles existed in the cross-section of the matrix that did not satisfy R. ij The case where the relationship is greater than 0.

[0099] In the matrix of the embodiment, it was confirmed that the average particle size of the plurality of hard phase particles contained in the cross section of the matrix was smaller than the average particle size of the plurality of binder phase particles contained in the cross section of the matrix. In the matrix of the comparative example, it was also confirmed that the average particle size of the plurality of hard phase particles contained in the cross section of the matrix was smaller than the average particle size of the plurality of binder phase particles contained in the cross section of the matrix.

[0100] In the matrix of the embodiment, it was confirmed that in the cross-section of the matrix, most of the multiple hard phase particles were surrounded by the solid solution phase and separated from the binder phase. On the other hand, it was confirmed that in the matrix of the comparative example, in the cross-section of the matrix, most of the multiple hard phase particles were not surrounded by the solid solution phase and were in contact with the hard phase particles or the binder phase.

[0101] Next, a chipping resistance test was conducted on the cermet cutting tools with the substrates of the embodiments and the cermet cutting tools with the substrates of the comparative examples. The conditions for the chipping resistance test are as follows.

[0102] <Damage Resistance Test (Turning)>

[0103] Workpiece to be machined: S45Cφ200 (4 slots, 25mm wide)

[0104] Cutting speed: 250 m / min

[0105] Feed: 0.25mm / rev

[0106] Cut-in depth: 1.0mm

[0107] Cutting condition: wet

[0108] Evaluation method: Number of impacts (times) until a defect occurs.

[0109] The number of impacts until the cermet tool including the substrate of the embodiment develops a defect is approximately 2000. On the other hand, the number of impacts until the cermet tool including the substrate of the comparative example develops a defect is approximately 1300. Thus, it can be confirmed that the cermet tool including the substrate of the embodiment has improved defect resistance compared to the cermet tool including the substrate of the comparative example.

[0110] As described above, a cermet cutting tool (cermet cutting tool 1, for example) comprises a matrix (matrix 2, for example), the matrix including a hard phase containing Ti (hard phase 5, for example), a binder phase containing at least one of Ni and Co (binder phase 6, for example), and a solid solution phase containing Ti and W (solid solution phase 7, for example). The hard phase includes a plurality of hard phase particles. In the cross-section of the matrix, the plurality of hard phase particles satisfy the relationship n2 < n1, where n1 represents the number of the plurality of hard phase particles contained in the cross-section of the matrix, and n2 represents the number of the plurality of hard phase particles contained in the cross-section of the matrix satisfying R ij The relationship <D represents the number of multiple hard phase particles, where D represents the average particle size of the multiple hard phase particles contained in the cross-section of the matrix, and R... ij Let i represent the distance between the i-th hard phase particle and the j-th hard phase particle among the multiple hard phase particles contained in the cross section of the matrix. i and j are natural numbers that satisfy the following conditions: i, j ≤ n1 and i < j or j < i.

[0111] Therefore, the cermet cutting tool according to the embodiment can improve wear resistance and chipping resistance.

[0112] Figure 1 The shape of the cermet cutting tool 1 shown is merely an example and does not limit the shape of the cermet cutting tool disclosed herein. The cermet cutting tool disclosed herein may, for example, include a rod-shaped body having a rotation axis and extending from a front end toward a rear end, a cutting edge located at a first end of the body, and a groove extending spirally from the cutting edge toward a second end of the body.

[0113] Here, examples of the use of cermet as cutting tools are described, but the uses of cermet in this disclosure are not limited to cutting tools.

[0114] Postscript (1):

[0115] A metal-ceramic cutting tool, comprising a substrate, wherein...

[0116] The matrix includes:

[0117] The hard phase contains Ti;

[0118] The binder phase contains at least one of Ni and Co; and

[0119] A solid solution phase containing Ti and W.

[0120] The hard phase comprises multiple hard phase particles.

[0121] In the cross-section of the matrix, the plurality of hard phase particles satisfy the relationship n2 < n1.

[0122] n1 represents the number of the plurality of hard phase particles contained in the cross section of the matrix.

[0123] n2 represents the cross-section of the matrix that contains elements satisfying R. ij The relationship between <D and the number of the plurality of hard phase particles.

[0124] D represents the average particle size of the plurality of hard phase particles contained in the cross section of the matrix.

[0125] R ij This represents the distance between the i-th and j-th hard phase particles among the plurality of hard phase particles contained in the cross-section of the matrix.

[0126] i and j are natural numbers that satisfy the following conditions: i, j ≤ n1 and i < j or j < i.

[0127] Postscript (2):

[0128] According to the metal-ceramic cutting tool described in Appendix (1), wherein,

[0129] In the cross-section of the matrix, the plurality of hard phase particles satisfy the relationship n2 < (n1 / 2).

[0130] Postscript (3):

[0131] According to the metal-ceramic cutting tools described in appendix (1) or (2), wherein,

[0132] In the cross-section of the matrix, the plurality of hard phase particles satisfy R ij A relationship greater than 0.

[0133] Postscript (4):

[0134] According to any one of the appendices (1) to (3), the metal-ceramic cutting tool, wherein,

[0135] The binder phase comprises multiple binder phase particles.

[0136] The average particle size of the multiple hard phase particles contained in the cross section of the matrix is ​​smaller than the average particle size of the multiple binder phase particles contained in the cross section of the matrix.

[0137] Postscript (5):

[0138] According to any one of the appendices (1) to (4), the metal-ceramic cutting tool, wherein,

[0139] In the cross-section of the matrix, the plurality of hard phase particles are surrounded by the solid solution phase and separated from the binder phase.

[0140] Postscript (6):

[0141] According to any one of the appendices (1) to (5), the metal-ceramic cutting tool, wherein,

[0142] The metal-ceramic cutting tool also has a coating layer applied to the substrate.

[0143] Postscript (7):

[0144] A cutting tool, the cutting tool comprising:

[0145] A handle extending from a front end toward a rear end, and having a groove on the front end side; and

[0146] The metal-ceramic cutting tool described in any one of notes (1) to (6) is located in the groove.

[0147] Further effects and / or variations can be readily derived by those skilled in the art. Therefore, the broader scope of the invention is not limited to the specific details and representative embodiments described above. Thus, various modifications can be made without departing from the spirit or scope of the general concept of the invention as defined by the appended technical solutions and their equivalents.

[0148] [Explanation of Labels in the Attached Image]

[0149] 1. Metal-ceramic cutting tools

[0150] 2. Matrix

[0151] 3. Coating layer

[0152] 5 Hard phase

[0153] 5i The i-th hard phase particle

[0154] 5j The j-th hard phase particle

[0155] 6. Binder phase

[0156] 7. Solid solution phase

[0157] 21 Through Hole

[0158] 70 Knife Handle

[0159] 73 Grooves

[0160] 75 screws

[0161] 100 Cutting tools.

Claims

1. A metal-ceramic cutting tool, comprising a substrate, wherein, The matrix includes: The hard phase contains Ti; The binder phase contains at least one of Ni and Co; and A solid solution phase containing Ti and W. The hard phase comprises multiple hard phase particles. In the cross-section of the matrix, the plurality of hard phase particles satisfy the relationship n2 < n1. n1 represents the number of the plurality of hard phase particles contained in the cross section of the matrix. n2 represents the cross-section of the matrix that contains elements satisfying R. ij The relationship between <D and the number of the plurality of hard phase particles. D represents the average particle size of the plurality of hard phase particles contained in the cross section of the matrix. R ij This represents the distance between the i-th and j-th hard phase particles among the plurality of hard phase particles contained in the cross-section of the matrix. i and j are natural numbers that satisfy the following conditions: i, j ≤ n1 and i < j or j < i.

2. The metal-ceramic cutting tool according to claim 1, wherein, In the cross-section of the matrix, the plurality of hard phase particles satisfy the relationship n2 < (n1 / 2).

3. The metal-ceramic cutting tool according to claim 1 or 2, wherein, In the cross-section of the matrix, the plurality of hard phase particles satisfy R ij A relationship greater than 0.

4. The metal-ceramic cutting tool according to any one of claims 1 to 3, wherein, The binder phase comprises multiple binder phase particles. The average particle size of the multiple hard phase particles contained in the cross section of the matrix is ​​smaller than the average particle size of the multiple binder phase particles contained in the cross section of the matrix.

5. The metal-ceramic cutting tool according to any one of claims 1 to 4, wherein, In the cross-section of the matrix, the plurality of hard phase particles are surrounded by the solid solution phase and separated from the binder phase.

6. The metal-ceramic cutting tool according to any one of claims 1 to 5, wherein, The metal-ceramic cutting tool also has a coating layer applied to the substrate.

7. A cutting tool, the cutting tool comprising: A handle extending from a front end toward a rear end, and having a groove on the front end side; and The metal-ceramic cutting tool according to any one of claims 1 to 6, located in the groove.

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