Cermet composite material, method for manufacturing the same, and cermet tool

Abstract

The main purpose of the present invention is to provide a cermet composite material capable of improving the bond strength between a cermet portion and a non-cermet portion even without being subjected to a high-temperature heat treatment.　This cermet composite material is characterized by having a cermet portion where hard carbides are dispersed in a metal phase and a non-cermet portion formed from an Ni-based alloy containing 50 mass% or more of Ni, wherein: the cermet portion is additively fabricated on the non-cermet portion; the cermet portion and the non-cermet portion have therebetween an intermediate layer in which the constituents of the cermet portion and the non-cermet portion are mixed; the non-cermet portion is formed from the Ni-based alloy containing Ti in the range of 3.0 mass% to 15.0 mass%, or from the Ni-based alloy containing Ti in the range of 0.5 mass% to less than 3.0 mass% and the total of 4 mass% to 5 mass% of Nb and Ta.

Description

Technical Field

[0001] The present invention relates to a cermet composite material having a cermet part and a non-cermet part, a manufacturing method thereof, and a cermet tool using the cermet composite material.

Background Art

[0002] Conventionally, inventions related to a method of joining a cermet excellent in wear resistance and another material such as steel by a sintering method, and a composite material manufactured by the manufacturing method are known (see Patent Document 1). Patent Document 1 discloses that a cemented carbide powder, which is a type of cermet, and a powder made of another material such as steel or nickel are placed in a mold, co-compressed, and then sintered at a high temperature to be joined, so that a strong metal bond is formed between the cemented carbide and the other material.

[0003] In addition, inventions related to a manufacturing method of a composite material of a cemented carbide and a non-cemented carbide, which is excellent in high-temperature strength and can suppress the occurrence of cracks and peeling, and a cemented carbide tool manufactured by the manufacturing method are known (see Patent Document 2). Patent Document 2 discloses a cermet composite material having a cemented carbide part made of a WC-Co-based cemented carbide and a base material part made of a metal containing at least one of Ni and Co in a total of 50% by mass or more, and having an intermediate layer containing components of the cemented carbide part and the base material part between the cemented carbide part and the base material part. The intermediate layer contains a part where the gamma phase fraction is 80% or more and the Vickers hardness is less than 700 HV. In this cermet composite material, since the intermediate layer contains a part where the gamma phase fraction is 80% or more and the Vickers hardness is less than 700 HV, cracks do not occur at the interface between the cemented carbide part and the base material part, and a strong bond between the cemented carbide part and the base material part can be achieved.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

[0005] Patent Document 1 states that a metallic bond is formed between the cemented carbide and the non-cemented carbide. However, in the sintering method, a region where the components of the cemented carbide and the non-cemented carbide are mixed is not sufficiently formed, and cracks may occur at the interface when high loads are applied.

[0006] Furthermore, the cermet composite material described in Patent Document 2 has a structure in which an intermediate layer containing components of both the cemented carbide and the base material is located between a cemented carbide part made of WC-Co cemented carbide and a base material part made of a metal containing at least 50% by mass or more of Ni and Co in total. It is believed that a strong bond is obtained due to the presence of this intermediate layer. On the other hand, Patent Document 2 discloses that the intermediate layer contains a certain amount of M6C carbide. In addition, reproduction experiments conducted by the inventors related to Patent Document 2 have confirmed the presence of free carbon in the intermediate layer. These M6C carbide and free carbon are considered harmful phases, and their presence may cause cracks to occur at the interface between the cemented carbide part and the base material part when a high load is applied. Although Patent Document 2 discloses that M6C carbide and free carbon can be diffused and eliminated by heat treatment at 1000°C to 1300°C, depending on the application, heat treatment at the above temperature is often difficult due to constraints on the base material.

[0007] The present invention has been made in view of the above-mentioned problems, and its main objective is to provide a cermet composite material having a cermet portion and a non-cermet portion, which can improve the bonding strength between the cermet portion and the non-cermet portion even without high-temperature heat treatment, a method for manufacturing the same, and a cermet tool. [Means for solving the problem]

[0008] To solve the aforementioned problems, the cermet composite material of the present invention comprises a cermet portion in which hard carbides are dispersed in a metal phase, and a non-cermet portion made of a Ni-based alloy containing 50% by mass or more of Ni, wherein the cermet portion is formed on the non-cermet portion by additive manufacturing, and has an intermediate layer between the cermet portion and the non-cermet portion in which the components of the cermet portion and the components of the non-cermet portion are mixed, wherein the non-cermet portion is made of the Ni-based alloy containing 3.0% by mass or more and 15.0% by mass or less of Ti, or the Ni-based alloy containing 0.5% by mass or more and less than 3.0% by mass of Ti, and a total of 4% by mass or more and 15% by mass or less of Nb and Ta.

[0009] Furthermore, the present invention relates to a method for manufacturing a cermet composite material, comprising: a cermet portion in which hard carbides are dispersed in a metal phase; and a non-cermet portion made of a Ni-based alloy containing 50% by mass or more of Ni and 3.0% by mass or more of Ti and 15.0% by mass or less; or a Ni-based alloy containing 50% by mass or more of Ni, 0.5% by mass or more of Ti and a total of 4% by mass or more of Nb and Ta and 15% by mass or less; a method for manufacturing a cermet composite material comprising: a preheating step of preheating the non-cermet portion to a temperature of 350°C or more and 800°C or less; and a composite material manufacturing step of forming a cermet portion on the non-cermet portion by additive manufacturing, thereby producing a cermet composite material having an intermediate layer between the non-cermet portion and the cermet portion in which the components of the non-cermet portion and the components of the cermet portion are mixed.

[0010] Furthermore, the cermet tool of the present invention is a cermet tool using the cermet composite material described above, and is characterized by having a machining portion for machining a workpiece and a base portion for supporting the machining portion, wherein the machining portion is the cermet portion and the side of the base portion facing the machining portion is the non-cermet portion. This specification includes the disclosures of Japanese Patent Application No. 2021-147789, which forms the basis of the priority claim of this application. [Effects of the Invention]

[0011] According to the present invention, the bonding strength between the cermet part and the non-cermet part can be improved even when heat treatment at a high temperature is not performed.

Brief Description of the Drawings

[0012] [Figure 1A] It is a schematic cross-sectional view showing an example of a cermet composite material according to an embodiment. [Figure 1B] It is a schematic cross-sectional view showing another example of a cermet composite material according to an embodiment. [Figure 2] It is a cross-sectional photograph showing the cermet composite material shown in FIG. 1A. [Figure 3] It is a graph showing the measurement results of the X-ray count number of tungsten by EPMA in the cermet composite materials shown in FIGS. 1A and 2. [Figure 4] It is a flowchart showing an example of a method for manufacturing a cermet composite material according to an embodiment. [Figure 5] It is a front view showing an example of a cermet tool according to an embodiment. [Figure 6] It is a cross-sectional view showing another example of a cermet tool according to an embodiment. [Figure 7] It is a cross-sectional photograph showing the observation result of poor fusion in the intermediate layer of Comparative Example 2. [Figure 8A] It is a backscattered electron image by SEM of the crystal structure in the intermediate layer of Comparative Example 1. [Figure 8B] It is a backscattered electron image by SEM of the crystal structure in the intermediate layer of Comparative Example 2. [Figure 8C] It is a backscattered electron image by SEM of the crystal structure in the intermediate layer of Example 1. [Figure 8D] It is a backscattered electron image by SEM of the crystal structure in the intermediate layer of Example 2. [Figure 8E] It is a backscattered electron image by SEM of the crystal structure in the intermediate layer of Example 3. [Figure 8F] It is a backscattered electron image by SEM of the crystal structure in the intermediate layer of Example 4. [Figure 9A] It is a TEM image of the crystal structure in the intermediate layer of Example 4. [Figure 9B] It is the result of elemental mapping by EDX of the crystal structure in the intermediate layer of Example 4. [Figure 9C] It is the selected area electron diffraction result of phase 50 in the intermediate layer of Example 4. [Figure 9D] It is the selected area electron diffraction result of phase 51 in the intermediate layer of Example 4. [Figure 9E] It is the selected area electron diffraction result of phase 52 in the intermediate layer of Example 4. [Figure 9F] It is the selected area electron diffraction result of phase 53 in the intermediate layer of Example 4. [Figure 9G] It is the selected area electron diffraction result of phase 54 in the intermediate layer of Example 4.

Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments of the cermet composite material of the present invention, its manufacturing method, and the cermet tool will be described with reference to the drawings and the like. The following description shows specific examples of the content of the present invention, and the present invention is not limited to these descriptions, and various changes and modifications can be made by those skilled in the art within the scope of the technical idea disclosed in this specification. Also, in all the drawings for explaining the present invention, those having the same function are denoted by the same reference numerals, and the repeated description thereof may be omitted.

[0014] As used herein, "~" described herein means including the numerical values described before and after as the lower limit value and the upper limit value. In the numerical ranges described stepwise in this specification, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value described in other stepwise numerical ranges. The upper limit value or the lower limit value of the numerical range described in this specification may also be replaced with the value shown in the examples.

[0015] When selecting materials from the group of materials exemplified below, you may select materials individually, in combination, or, to the extent that it does not contradict what is disclosed herein, you may also select materials other than those exemplified below, to the extent that it does not contradict what is disclosed herein.

[0016] [Cermet composite material] Figures 1A and 1B are schematic cross-sectional views showing an example and another example of a cermet composite material according to the embodiment. Figure 2 is a cross-sectional photograph showing the cermet composite material shown in Figure 1A.

[0017] The cermet composite material 10 shown in Figure 1A has a cermet portion 1 and a non-cermet portion 2, and the cermet portion 1 is formed on the non-cermet portion 2 by additive manufacturing. The cermet composite material 10 also has an intermediate layer 3 between the cermet portion 1 and the non-cermet portion 2 in which the components of the cermet portion 1 and the non-cermet portion 2 are mixed. The cermet portion 1 has a metal phase with one of the following as the binder phase: cobalt (Co), nickel (Ni), iron (Fe), etc., in which one of the following hard carbides is dispersed: for example, tungsten carbide (WC), niobium carbide (NbC), tantalum carbide (TaC), molybdenum carbide (MoC), vanadium carbide (VC), etc. The non-cermet portion 2 is made of a Ni-based alloy containing 50% by mass or more of Ni and 3.0% by mass or more and 15.0% by mass or less of Ti.

[0018] The non-cermet portion 2 of the cermet composite material 10 contains 3.0% to 15.0% by mass of Ti, which has excellent carbide-forming ability. Therefore, when the cermet portion 1 is fabricated on the non-cermet portion 2 by additive manufacturing, the intermediate layer 3 formed is less prone to the formation of brittle phases such as M6C carbides and free carbon. The intermediate layer 3 has a structure with excellent crack resistance, in which a certain amount or more of NaCl-type MC carbides are finely dispersed in the gamma phase. Thus, the bonding strength between the cermet portion 1 and the non-cermet portion 2 can be improved, and the amount of M6C carbides and free carbon in the intermediate layer 3, where the components of the cermet portion 1 and the non-cermet portion 2 are mixed, can be reduced.

[0019] On the other hand, the cermet composite material 10 shown in Figure 1B has, in addition to the configuration of the cermet composite material 10 shown in Figure 1A, a hard coating layer 4 provided on the surface of the cermet portion 1. The hard coating layer 4 can be formed, for example, by nitriding the surface of the cermet portion 1, or by a film formation method such as CVD (Chemical Vapor Deposition) or PVD (Physical Vapor Deposition). The material of the hard coating layer 4 is not particularly limited, but at least one carbide, nitride, oxide, or carbonitride from the group consisting of Ti, Al, and Cr is preferred. Examples include titanium carbide (TiC), titanium nitride (TiN), titanium carbonitride (TiCN), aluminum oxide (Al2O3), titanium aluminum nitride (TiAlN), and chromium nitride (CrN). The presence of the hard coating layer 4 on the surface of the cermet portion 1 in the cermet composite material 10 makes it possible to improve the wear resistance of the cermet portion 1.

[0020] A further example of the cermet composite material according to the embodiment has a cermet portion 1 and a non-cermet portion 2, similar to the cermet composite material 10 shown in Figure 1A, wherein the cermet portion 1 is formed on the non-cermet portion 2 by additive manufacturing, and an intermediate layer 3 is provided between the cermet portion 1 and the non-cermet portion 2, in which the components of the cermet portion 1 and the components of the non-cermet portion 2 are mixed. In this example, similar to the cermet composite material 10 shown in Figure 1A, the cermet portion 1 has a metal phase with cobalt (Co), nickel (Ni), iron (Fe), etc. as the binder phase, in which hard carbides such as tungsten carbide (WC), niobium carbide (NbC), tantalum carbide (TaC), molybdenum carbide (MoC), and vanadium carbide (VC) are dispersed. On the other hand, unlike the cermet composite material 10 shown in Figure 1A, the non-cermet portion 2 is made of a Ni-based alloy containing 50% by mass or more of Ni, 0.5% by mass or more and less than 3.0% by mass of Ti, and a total of 4% by mass or more and 15% by mass or less of Nb and Ta.

[0021] In this example, the non-cermet portion 2 contains only 0.5% to less than 3.0% by mass of Ti, but contains a total of 4% to 15% by mass of Nb and Ta, which have high carbide-forming ability. Therefore, when the cermet portion 1 is fabricated on the non-cermet portion 2 by additive manufacturing, the intermediate layer 3 formed is less prone to the formation of brittle phases such as M6C carbides and free carbon. The intermediate layer 3 has a structure with excellent crack resistance, in which a certain amount or more of NaCl-type MC carbides are finely dispersed in the gamma phase. Thus, the bonding strength between the cermet portion 1 and the non-cermet portion 2 can be improved, and the amount of M6C carbides and free carbon in the intermediate layer 3 can be reduced.

[0022] The various components of the cermet composite material according to this embodiment will be described in more detail below.

[0023] (Cermet section) The cermet portion 1 mainly consists of a metal phase with one of the following as the binder phase: cobalt (Co), nickel (Ni), iron (Fe), etc., in which a hard carbide such as tungsten carbide (WC), niobium carbide (NbC), tantalum carbide (TaC), molybdenum carbide (MoC), or vanadium carbide (VC) is dispersed. Preferably, the cermet portion is made of a WC-Co cemented carbide, for example, in which a hard carbide of WC is dispersed in a metal phase with Co as the binder phase.

[0024] In the cermet portion 1, the toughness improves as the amount of metallic phases such as Co, Ni, and Fe increases, thereby suppressing the occurrence of cracks and delamination during molding. On the other hand, strength and hardness decrease with increasing amounts of metallic phases. Therefore, it is preferable that the cermet portion 1 contains at least one of Co, Ni, and Fe in an amount of 20% to 50% by mass, with the remainder being hard carbide. Specifically, if the cermet portion 1 is made of, for example, a WC-Co cemented carbide, it is preferable that it contains 20% to 50% by mass of Co, with the remainder being tungsten carbide. This prevents cracks and delamination in the cermet portion 1, and provides toughness, strength, and hardness suitable for use as a tool, for example. The Vickers hardness of the cermet portion 1 is preferably, for example, 400 HV to 1000 HV.

[0025] The cermet portion 1 may further contain trace amounts of chromium (Cr), vanadium (V), titanium (Ti), tantalum (Ta), niobium (Nb), etc. Cr and V can suppress carbide grain growth and improve oxidation resistance. Ti, Ta, and Nb have the effect of expanding the sound phase region of the structure. Furthermore, the finer the carbide particles, the better the strength and toughness. Therefore, it is desirable that the average particle size of the carbides contained in the cermet portion 1 be 50 μm or less. Here, the average particle size of the carbide particles contained in the cermet portion 1 can be determined from the average of the equivalent circular diameters of each particle on the test surface obtained by cutting the cermet portion 1.

[0026] (Non-cermet part) The non-cermet portion 2 (base material portion) is made of a Ni-based alloy containing 50% by mass or more of Ni and 3.0% by mass or more of Ti and 15.0% by mass or less, or a Ni-based alloy containing 50% by mass or more of Ni, 0.5% by mass or more of Ti and less than 3.0% by mass, and a total of 4% by mass or more of Nb and Ta and 15% by mass or less. The non-cermet portion 2 is not particularly limited as long as it is made of these Ni-based alloys, but it may also be made of a Ni-based alloy that, in addition to the components of these Ni-based alloys, appropriately contains other metallic elements or non-metallic elements.

[0027] Ni-based alloys containing 50% or more by mass of Ni and 3.0% to 15.0% by mass of Ti may also contain one or more elements selected from chromium (Cr), cobalt (Co), molybdenum (Mo), tungsten (W), niobium (Nb), aluminum (Al), iron (Fe), zirconium (Zr), tantalum (Ta), vanadium (V), hafnium (Hf), manganese (Mn), silicon (Si), lanthanum (La), magnesium (Mg), carbon (C), and boron (B), in addition to Ni and Ti. The Ni-based alloy may also contain unavoidable impurities.

[0028] A nickel-based alloy containing 50% or more by mass of Ni, 0.5% or more by mass of Ti and a total of 4% or more by mass of Nb and Ta, may also contain one or more elements selected from chromium (Cr), cobalt (Co), molybdenum (Mo), tungsten (W), aluminum (Al), iron (Fe), zirconium (Zr), vanadium (V), hafnium (Hf), manganese (Mn), silicon (Si), lanthanum (La), magnesium (Mg), carbon (C), and boron (B), in addition to Ni, Nb, and Ta. The nickel-based alloy may also contain unavoidable impurities.

[0029] Generally, Ni-based alloys are alloys with a gamma phase as the main phase. Therefore, when the non-cermet portion 2 is made of a Ni-based alloy, the gamma phase fraction of the intermediate layer 3 increases, which can suppress a significant decrease in the toughness of the intermediate layer 3. However, in the case of typical Ni-based alloys, when the cermet portion 1 and the non-cermet portion 2 are mixed, brittle phases such as M6C carbides and free carbon are formed in the intermediate layer 3. When a Ni-based alloy is used for the non-cermet portion 2, the gamma phase fraction of the intermediate layer 3 increases, and the toughness of the intermediate layer 3 increases, making it less likely to crack during manufacturing. However, if these brittle phases are present, cracking may occur in the intermediate layer 3 when a strong load is applied to the cermet composite material 10.

[0030] Therefore, by including 3.0 mass% or more of Ti in the non-cermet portion 2, the formation of M6C carbides and free carbon in the intermediate layer 3 becomes less likely. This is thought to be because Ti has a high carbide-forming ability, that is, Ti has a property of readily bonding with carbon, which makes it less likely for free carbon to be formed, and as a result of the formation of NaCl-type MC carbides etc., in which Ti is bonded with carbon, the formation of M6C carbides is relatively less likely. Since MC carbides etc. are dispersed relatively finely, the crack resistance is higher compared to the case in which coarsely crystallized M6C carbides form in a dendrite-like manner. For similar reasons, it is more desirable for the non-cermet portion 2 to contain 4 mass% or more of Ti. On the other hand, if the amount of Ti in the non-cermet portion 2 is greater than 15.0 mass%, the stability of M6C carbides increases again, and M6C carbides begin to crystallize. In addition, severe oxidation occurs during the addition manufacturing of the cermet portion 1, resulting in poor fusion, and poor fusion can be the starting point for fracture. For these reasons, the Ti content of the non-cermet portion 2 must be 15.0 mass% or less, and more preferably 14 mass% or less. Therefore, when the non-cermet portion 2 contains 3.0 mass% to 15.0 mass% of Ti, a structure with high crack resistance in the intermediate layer 3 is obtained, and defects such as poor fusion are less likely to occur. When the non-cermet portion 2 contains 4 mass% to 14 mass% of Ti, these effects become even more effective.

[0031] On the other hand, Nb and Ta also have relatively high carbide-forming abilities, although not as high as Ti. Therefore, even when the non-cermet portion 2 contains 0.5% to less than 3.0% by mass of Ti and a total of 4% to 15% by mass of Nb and Ta, the formation of MC carbides is similarly promoted and crack resistance is improved, so it can be treated the same as the case of the non-cermet portion 2 containing 3.0% to 15.0% by mass of Ti. Since Nb and Ta are congeneral elements and their standard energies for carbide formation reactions are similar, when the total amount of Nb and Ta is 4% to 15% by mass, both Nb and Ta may be included, or Nb alone may be included at a rate of 4% to 15% by mass, or Ta alone may be included at a rate of 4% to 15% by mass.

[0032] Furthermore, if the non-cermet portion 2 contains Cr and Fe above a certain level, the concentration distribution during the melting and solidification process in the addition manufacturing of the cermet portion 1 can lead to Cr concentration in the final solidified portion. This can result in the formation of brittle intermetallic compounds such as the σ phase and Laves phase in the intermediate layer 3, increasing the likelihood of cracking. Therefore, in the non-cermet portion, the Cr content is preferably 19.0% by mass or less and the Fe content is preferably 25.0% by mass or less, more preferably 14.0% by mass or less and 18.0% by mass or less, and even more preferably 10.0% by mass or less and 12.0% by mass or less.

[0033] Furthermore, as a carbide very similar to M6C carbide, 12 There are C carbides, and although these carbides differ in the ratio of carbon to metal elements, their crystal structures and properties are known to be very similar. Which carbide is formed depends on conditions such as the composition of the intermediate layer 3 and the cooling rate during addition. Therefore, the above-mentioned M6C carbide is M 12 It may also be C carbide. That is, in the intermediate layer 3, at least a portion of the M6C carbide mentioned above is replaced by M 12 C carbides may be formed.

[0034] (Middle class) The intermediate layer 3 is formed between the cermet portion 1 and the non-cermet portion 2, and is a region where the components of the cermet portion 1 and the components of the non-cermet portion 2 are mixed. The intermediate layer 3 is generated at and near the bonding interface between the cermet portion 1 and the non-cermet portion 2 during the manufacturing of the cermet composite material 10.

[0035] The thickness of the intermediate layer 3 should preferably be 500 μm or more. If the thickness of the intermediate layer 3 is 500 μm or more, the bond between the cermet portion 1 and the non-cermet portion 2 becomes strong. On the other hand, if the thickness of the intermediate layer 3 is less than 500 μm, sufficient metallic bonding is not obtained, and there is a high possibility that cracks or delamination will occur in the intermediate layer 3 when a strong load is applied to the cermet composite material 10.

[0036] From the viewpoint of improving toughness, the intermediate layer 3 is preferably composed of dispersed carbide particles. The carbide particles are not particularly limited, but for example, it is preferable that they include at least one of MC carbide and tungsten carbide.

[0037] When carbide particles contain MC carbides, the area ratio of MC carbides is preferably, for example, 3% to 24%. If it is less than 3%, the effect of suppressing free carbon and M6C carbides is insufficient. If it exceeds 24%, oxidation resistance decreases significantly, and crack resistance also decreases due to the excess carbides.

[0038] Furthermore, the area ratio and average diameter of MC carbides and tungsten carbides can be calculated using electron backscatter diffraction (EBSD). For example, by scanning a 200 μm × 200 μm area in the center of the intermediate layer of a cross-section along the lamination direction of a cermet composite material, and averaging the area ratio and equivalent diameter of the MC carbides and tungsten carbides observed on the measurement screen. Alternatively, they can be calculated using a field emission scanning electron microscope (FE-SEM) by, for example, binarizing a backscattered electron image (BSE image) captured at 1000x magnification.

[0039] From the viewpoint of improving toughness, the intermediate layer 3 is preferably low in or free of M6C carbides and free carbon. The area ratio of M6C carbides is preferably 24% or less, more preferably 20% or less, and especially preferably 10% or less. This is because problems due to embrittlement can be suppressed by keeping these levels below the upper limits. Similarly, the area ratio of free carbon is preferably 1.5% or less, more preferably 1% or less, and especially preferably 0.5% or less. This is because problems due to embrittlement can be suppressed by keeping these levels below the upper limits.

[0040] The method for determining the presence of M6C carbides and free carbon is not particularly limited, but examples include X-ray diffraction (XRD), observation with a scanning electron microscope (SEM), and EBSD analysis. The area ratio and average diameter of M6C carbides and free carbon can be calculated using the EBSD method, for example, by scanning a 200 μm × 200 μm area in the center of the intermediate layer of a cross-section along the lamination direction of the cermet composite material, and averaging the area ratio and equivalent diameter of the M6C carbides and free carbon observed on the measurement screen. Alternatively, it can be calculated by binarizing a BSE image taken at 1000x magnification.

[0041] The porosity fraction of the intermediate layer 3 is preferably 1% or less from the viewpoint of suppressing a decrease in the fatigue life of the cermet composite material 10. The porosity fraction can be calculated, for example, by determining the area of ​​the sample cross-section through microscopic observation of the sample cross-section and finding the area of ​​the visible voids.

[0042] From the viewpoint of improving toughness, it is desirable that the intermediate layer 3 contains little to no brittle intermetallic compounds such as the σ phase and Laves phase. In the intermediate layer 3, the area ratio of brittle intermetallic compounds, including the σ phase and Laves phase, is preferably 8% or less, more preferably 5% or less, and especially preferably 2% or less. This is because problems due to embrittlement can be suppressed by keeping it below these upper limits. The σ phase and Laves phase are basically phases where Cr is concentrated. Therefore, the area ratio of intermetallic compounds, including the σ phase and Laves phase, can be calculated, for example, by performing elemental mapping of Cr using energy dispersive X-ray spectroscopy (EDX).

[0043] The presence of the intermediate layer 3 can be determined from its appearance, as shown in Figure 2. On the other hand, the boundary between the cermet portion 1 and the intermediate layer 3, and the boundary between the intermediate layer 3 and the non-cermet portion 2, may not be clearly distinguishable from their appearance, for example, when observed with a microscope. In this case, the boundary between the cermet portion 1 and the intermediate layer 3, and the boundary between the intermediate layer 3 and the non-cermet portion 2, can be defined, for example, by an electron probe microanalyzer (EPMA).

[0044] Here, we will explain a method for defining the boundary between the cermet portion 1 and the intermediate layer 3, and the boundary between the intermediate layer 3 and the non-cermet portion 2, using EPMA, in the case where the cermet portion 1 of the cermet composite material 10 shown in Figure 1A is made of WC-Co cemented carbide.

[0045] In this method, first, as shown in Figure 2, the cermet composite material 10 is cut so that the cermet portion 1 and the non-cermet portion 2 can be observed in the same cross-section. Note that, as shown in Figure 2, the cermet portion 1 and the non-cermet portion 2 can be easily distinguished. Next, line analysis is performed using EPMA, setting the spot size to 0 μm in 20 μm steps, from the cermet portion 1 toward the non-cermet portion 2, and the X-ray count of tungsten is measured.

[0046] Figure 3 is a graph showing the measurement results of the tungsten X-ray count by EPMA in the cermet composite material shown in Figures 1A and 2. In Figure 3, the horizontal axis represents the measurement position [μm], which is the distance from the measurement start point, and the vertical axis represents the tungsten X-ray count. The substantial boundary between the cermet portion 1 (WC-Co cemented carbide portion) and the intermediate layer 3, and the substantial boundary between the intermediate layer 3 and the non-cermet portion 2 (alloy portion), can be defined, for example, by the variation range of the tungsten X-ray count.

[0047] Specifically, in a cermet composite material 10 where the cermet portion 1 is made of WC-Co cemented carbide, for example, in the intermediate layer 3, the fluctuation range of the tungsten X-ray count between adjacent analysis points is about ±10%, whereas in the cermet portion 1, the fluctuation range of the count between adjacent analysis points tends to be ±20% or more. Furthermore, in the non-cermet portion 2, the tungsten X-ray count and the fluctuation range of said count tend to be much smaller compared to the cermet portion 1 and the intermediate layer 3. For example, in Figure 3, it can be seen that in the intermediate layer 3, the fluctuation range of the tungsten X-ray count changes as a result of the mixing of the components of the cermet portion 1 and the components of the non-cermet portion 2. Therefore, by measuring the X-ray count of the constituent elements of the carbide in the cermet portion 1 using EPMA on the cross-section of the cermet composite material 10, the substantial boundary between the cermet portion 1 and the intermediate layer 3 and the substantial boundary between the intermediate layer 3 and the non-cermet portion 2 can be defined.

[0048] As described above, according to the embodiment, a cermet composite material 10 is provided which has a cermet portion 1 and a non-cermet portion 2, wherein the cermet portion 1 is formed on the non-cermet portion 2 by additive manufacturing, and which can improve the bonding strength between the cermet portion 1 and the non-cermet portion 2, and can reduce the amount of M6C carbides and free carbon in the intermediate layer 3 in which the components of the cermet portion 1 and the components of the non-cermet portion 2 are mixed.

[0049] [Manufacturing method for cermet composite materials] Figure 4 is a flow chart showing an example of a method for manufacturing a cermet composite material according to the embodiment. The cermet composite material manufacturing method S10 shown in Figure 4 is a method for manufacturing a cermet composite material 10 according to an embodiment having a cermet portion 1 and a non-cermet portion 2. The cermet composite material manufacturing method S10 includes a preheating step S1 and a composite material manufacturing step S2. The cermet composite material manufacturing method S10 may further include a heat treatment step S3. The various components of the cermet composite material manufacturing method according to this embodiment will be described in more detail below.

[0050] (Preheating process) The preheating step S1 is a step of preheating a non-cermet part 2, which is made of a Ni-based alloy containing 50% or more by mass of Ni and 3.0% to 15.0% by mass of Ti, or a Ni-based alloy containing 50% or more by mass of Ni, 0.5% to less than 3.0% by mass of Ti, and a total of 4% to 15% by mass of Nb and Ta, to a temperature of 350°C to 800°C. The non-cermet part 2 to be preheated is the same as the non-cermet part 2 described in the [cermet composite material] section above, except that the cermet part 1 is not formed on it by additive manufacturing. The method of preheating in the preheating step S1 is not particularly limited, but examples include preheating using high-frequency induction heating, gas burners, infrared electric heaters, heating furnaces, electron beams or laser irradiation, etc. In the preheating step S1, the non-cermet part 2 is preheated to a temperature of 800°C or lower from the viewpoint of preventing deformation due to its own weight. Furthermore, in the preheating step S1, it is desirable to preheat the non-cermet portion 2 to a temperature of 500°C or higher.

[0051] (Composite material manufacturing process) The composite material manufacturing process S2 is a process for manufacturing a cermet composite material having an intermediate layer 3 between the non-cermet portion 2 and the cermet portion 1, in which the components of the non-cermet portion 2 and the components of the cermet portion 1 are mixed. The additive manufacturing method is not particularly limited, but examples include directed energy deposition methods such as laser metal deposition, powder bed fusion bonding, and plasma powder cladding. In the directed energy deposition additive manufacturing method, the material powder of the cermet portion 1 is melted using a heat source such as a laser, electron beam, plasma, or arc, and the molten material powder is attached to the non-cermet portion 2 and solidified, thereby layering and manufacturing the cermet portion 1 on top of the non-cermet portion 2.

[0052] The material powder for the cermet portion 1 is a powder mixture of a hard carbide powder such as WC, NbC, TaC, MoC, or VC, and a metal binder such as Co, Ni, or Fe. For example, a WC-Co cemented carbide powder, which is a mixture of WC hard carbide powder and a Co binder, is preferable as the material powder for the cermet portion 1.

[0053] In the composite material manufacturing process S2, the cermet portion 1 is fabricated on the non-cermet portion 2 by additive manufacturing, causing the components of the cermet portion 1 and the non-cermet portion 2 to mix at and near the interface between the cermet portion 1 and the non-cermet portion 2. As a result, an intermediate layer 3 is formed between the cermet portion 1 and the non-cermet portion 2, and a cermet composite material having the intermediate layer 3 between the cermet portion 1 and the non-cermet portion 2 is obtained.

[0054] Furthermore, preheating the non-cermet portion 2 to a temperature of 350°C or higher in the preheating step S1 can suppress the occurrence of cracks and delamination between the cermet portion 1 and the non-cermet portion 2 in the composite material manufacturing step S2. Specifically, preheating the non-cermet portion 2 to a certain temperature or higher in the preheating step S1 reduces the cooling rate of the material to be melt-bonded during the additive manufacturing of the cermet portion 1 in the composite material manufacturing step S2, thereby suppressing hardening of the cermet portion 1 and low-temperature cracking due to diffusing hydrogen.

[0055] Furthermore, preheating the non-cermet portion 2 in the preheating step S1 makes the temperature gradient of the cermet portion 1 during additive manufacturing in the composite material manufacturing step S2 gentler, which suppresses deformation due to thermal stress and reduces residual stress. In addition, preheating the non-cermet portion 2 to a temperature of 500°C or higher in the preheating step S1 can suppress the occurrence of minute cracks in the composite material manufacturing step S2.

[0056] (Heat treatment process) The heat treatment step S3 is a step in which the cermet composite material 10 is heat-treated at a temperature of 1000°C to 1300°C after the composite material manufacturing step S2. The method for manufacturing the cermet composite material S10 may further include the heat treatment step S3. If the heat treatment step S3 is further included, M6C carbides and free carbon present in the cermet part 1 formed in the composite material manufacturing step S2 can be diffused or eliminated.

[0057] Since M6C carbides and free carbon are brittle phases, their presence reduces the toughness of the cermet portion 1. Therefore, by diffusing or eliminating the M6C carbides and free carbon present in the cermet portion 1 during the heat treatment process S3, the toughness of the cermet portion 1 can be improved, making it suitable for applications where cracking is likely to occur, such as under high loads. From the viewpoint of further improving the toughness of the cermet portion 1 by more effectively diffusing or eliminating the M6C carbides and free carbon present in the cermet portion 1, it is desirable to heat-treat the cermet composite material 10 at a temperature of 1200°C to 1300°C during the heat treatment process S3.

[0058] (others) Furthermore, the manufacturing method S10 of the cermet composite material according to the embodiment may further include a cutting step before or after the heat treatment step S3 in which the cermet composite material is cut. This can further improve the shape accuracy of the cermet composite material. Also, the cermet composite material according to the embodiment described in the [cermet composite material] section may be manufactured, for example, by the manufacturing method according to the embodiment.

[0059] [Cermet Tools] Next, a cermet tool according to the embodiment will be described with reference to Figures 1A to 4 and Figure 5. Figure 5 is a front view showing an example of a cermet tool according to the embodiment.

[0060] The cermet tool 20 shown in Figure 5 is a punch for a hot forging die. Note that the cermet tool according to this embodiment is not limited to a punch for a hot forging die; for example, it can be used as a processing part 21, having a working surface that performs cutting, shaping, moving, holding, etc., on a workpiece.

[0061] The cermet tool 20 according to the embodiment is a tool using the cermet composite material 10 according to the embodiment. The cermet tool 20 has a machining section 21 for machining a workpiece and a base section 22 that supports the machining section 21. The machining section 21 of the cermet tool 20 is the cermet section 1 of the cermet composite material 10 according to the embodiment, and the base section 22 of the cermet tool 20 is the non-cermet section 2 of the cermet composite material 10 according to the embodiment. That is, the cermet tool 20 has an intermediate layer 3 between the cermet section 1 that constitutes the machining section 21 and the non-cermet section 2 that constitutes the base section 22.

[0062] Conventional forging dies often use tool steel, which has excellent high-temperature strength and wear resistance. However, when performing hot forging, tool steel mainly composed of Fe softens at the forging temperature, resulting in a short die life. In contrast, the cermet tool 20 according to this embodiment has a cermet portion 1 for the processed portion 21, which provides excellent high-temperature strength and extends the die life.

[0063] Furthermore, conventional tools using cermets such as cemented carbide are obtained, for example, by mixing and sintering a Co-based alloy consisting of WC particles and a binder. While cermets have high hardness and excellent wear resistance, they have poor toughness and deteriorate due to mechanical impacts and thermal shock associated with their thermal history. Increasing the Co content of the Co-based alloy is effective in improving the toughness of cermets, but the large dimensional changes during sintering remain a challenge.

[0064] In contrast, the cermet tool 20 according to the embodiment can be manufactured by the method for manufacturing a cermet composite material using additive manufacturing technology, as described above. Therefore, it becomes possible to create near-net-shape machining parts 21 with complex shapes, and to create tools with unprecedented shapes and functions.

[0065] Furthermore, the processed part 21 formed by additive manufacturing has a higher density than conventional tools manufactured by sintering, and exhibits less dimensional change even after heat treatment following formation. Moreover, in the cermet tool 20 according to the embodiment, by using the cermet composite material 10 according to the embodiment described above, even when the processed part 21, which consists of the cermet part 1, is formed on a base part 22, which consists of a non-cermet part 2 with a different composition, delamination and cracking between the processed part 21 and the base part 22 can be suppressed. In other words, by using a non-cermet part 2 made of a Ni-based alloy containing a certain amount of Ti, or a Ni-based alloy containing a certain amount of Nb and Ta in addition to Ti, an intermediate layer 3 with good toughness and hardness can be formed, and the bonding strength between the processed part 21 and the base part 22 can be increased.

[0066] Therefore, according to the embodiment, it is possible to provide a cermet tool 20 with excellent bonding strength of the processing part 21, which is crack-free with no peeling or cracking between the processing part 21 and the base part 22, and which can withstand strong external loads. Thus, the cermet tool 20 can be made to have an even longer lifespan as a tool used at high temperatures such as in hot forging. In addition, since the raw material for cermet is expensive, the raw material cost can be reduced by making the processing part 21 that the tool acts on the workpiece out of cermet and constructing the other parts from different materials.

[0067] Figure 6 is a cross-sectional view showing another example of a cermet tool according to the embodiment. The cermet tool 40 shown in Figure 6 is also a punch for a hot forging die. Note that the cermet tool 40 according to this embodiment is not limited to a punch for a hot forging die, but can be used, for example, for tools of other shapes, such as hot forging dies or press dies.

[0068] The cermet tool 40 according to the embodiment is a tool using the cermet composite material 10 according to the embodiment. The cermet tool 40 has a machining section 41 for machining a workpiece, a base body (the part of the base opposite to the machining section) 43 that supports the machining section 41, and further a base underlay layer (the machining section side of the base) 42 that is positioned between the base body 43 and the machining section 41. The machining section 41 of the cermet tool 40 is the cermet section 1 of the cermet composite material 10 according to the embodiment, and the base underlay layer 42 of the cermet tool 40 is the non-cermet section 2 of the cermet composite material 10 according to the embodiment.

[0069] The base body 43 is made of an Fe-based alloy, such as hot work tool steel like SKD61. Specifically, the machining portion 41 of the cermet tool 40 has an intermediate layer 3 between the cermet portion 1 that constitutes the machining portion 41 and the non-cermet portion 2 that constitutes the base underlayment 42. Furthermore, the base underlayment 42 (non-cermet portion 2) of the cermet tool 40 is formed on the base body 43 by additive manufacturing using the additive manufacturing method described in the (composite material manufacturing process) section of the [method for manufacturing cermet composite material], with the Ni-based alloy powder that constitutes the non-cermet portion described in the (non-cermet portion) section of the [cermet composite material] used as the material powder for the base underlayment 42.

[0070] When the base body 43 is an Fe-based alloy, heat treatment at 1000°C to 1300°C to burn off M6C carbides and free carbon is undesirable because it causes a decrease in hardness due to dimensional changes and changes in the metal structure. In the cermet tool 40, a region where the components of both are mixed is formed between the underlayment layer 42 and the base body 43. However, since the amount of carbon and tungsten contained in the base body 43 (e.g., hot work tool steel) is less than that in the cermet part, the crack resistance of the region formed between the underlayment layer 42 and the base body 43 is sufficiently high. By manufacturing the highly wear-resistant cermet part only in areas of the tool that experience heavy wear using additive manufacturing, the cycle time required for manufacturing and the thermal impact on the base body 43 can be reduced. High-temperature heat treatment is not required regardless of whether the base body is an Fe-based alloy or not, but as mentioned above, when the base body 43 is an Fe-based alloy, high-temperature heat treatment is undesirable, and high crack resistance at the interface can be maintained without high-temperature heat treatment. [Examples]

[0071] The following provides a more detailed description of the cermet composite material according to the embodiment, its manufacturing method, and the cermet tool, with reference to examples and comparative examples.

[0072] First, six alloys with different compositions, No. 1 to No. 6, as shown in Table 1 below, were prepared as materials for the non-cermet portion. The units for the compositions shown in Table 1 are mass%, and "Bal" indicates the "remainder".

[0073] [Table 1]

[0074] [Example 1] First, as the non-cermet portion, Ni-based alloy No. 2 shown in Table 1 was used, and a preheating process was performed to preheat the non-cermet portion to a temperature of 500°C to 700°C. Next, a composite material fabrication process was performed in which a cermet portion was fabricated on top of the non-cermet portion by additive manufacturing, and a cermet composite material as shown in Figure 1A was produced, having an intermediate layer between the non-cermet portion and the cermet portion in which the components of the non-cermet portion and the cermet portion are mixed. For additive manufacturing, WC-Co cemented carbide powder with a Co content of 40 mass%, a type of cermet, was used as the additive manufacturing material, and laser deposition using the directed energy deposition method was performed. The cermet portion was fabricated by depositing the material in 9 passes per layer, with a height of 20 mm, and was stacked over approximately 40 layers. The additive manufacturing conditions shown in Table 2 are shown below. The additive manufacturing conditions shown in Table 2 were set so that the heat input to the powder was relatively low in order to prevent cracking between the non-cermet portion and the cermet portion. In Example 1, a heat treatment step, such as heat treatment at a temperature of 1000°C to 1300°C, was not performed after the composite material manufacturing process.

[0075] [Table 2]

[0076] [Example 2] A cermet composite material was fabricated in the same manner as in Example 1, except that material No. 3 shown in Table 1 was used for the non-cermet portion.

[0077] [Example 3] A cermet composite material was fabricated in the same manner as in Example 1, except that material No. 5 shown in Table 1 was used for the non-cermet portion.

[0078] [Example 4] A cermet composite material was fabricated in the same manner as in Example 1, except that material No. 6 shown in Table 1 was used for the non-cermet portion.

[0079] [Comparative Example 1] A cermet composite material was fabricated in the same manner as in Example 1, except that the non-cermet portion was made from material No. 1 shown in Table 1.

[0080] [Comparative Example 2] A cermet composite material was fabricated in the same manner as in Example 1, except that material No. 4 shown in Table 1 was used for the non-cermet portion.

[0081] [evaluation] Penetrant testing and cross-sectional observation were performed on the cermet composite materials of Examples 1 to 4, Comparative Example 1, and Comparative Example 2. As a result, no cracks or defects were found in Examples 1 to 4 and Comparative Example 1, and sound cermet composite materials were produced. On the other hand, a large amount of fusion defects were observed in the intermediate layer of Comparative Example 2. In Table 3 below, the "presence or absence of cracks or defects" is indicated as "good" or "poor." Figure 7 is a cross-sectional photograph showing the observation results of fusion defects in the intermediate layer of Comparative Example 2. Component analysis of the interior of fusion defect 5 revealed the presence of titanium oxide. Therefore, it is thought that if the amount of titanium in the non-cermet portion is too high, severe oxidation occurs during additive manufacturing, which causes fusion defects.

[0082] Figures 8A to 8F show the SEM backscattered electron images (BEI) of the crystal structure in the intermediate layers of Comparative Example 1, Comparative Example 2, Example 1, Example 2, Example 3, and Example 4, respectively.

[0083] As shown in Figure 8A, in Comparative Example 1, which used a non-cermet portion with low amounts of Ti, Nb, and Ta, coarse M6C carbides 30 and free carbon 31 were observed in the intermediate layer. On the other hand, as shown in Figures 8C and 8D, in Examples 1 and 2, which used a non-cermet portion containing 4.6 mass% and 10.0 mass% Ti, a microstructure was obtained in which NaCl-type MC carbides 32 and hexagonal tungsten carbides 33 were finely dispersed in the intermediate layer, and M6C carbides 30 and free carbon 31 were either absent or crystallized to a negligible degree. As shown in Figure 8E and Table 3 described later, in Example 3, when the amount of Ti in the non-cermet portion was 3.6 mass%, M6C carbides 30 were observed in the intermediate layer, but not in large quantities, and the sum of the area percentages of NaCl-type MC carbides 32 and hexagonal tungsten carbides 33 was greater than the area percentage of M6C carbides 30. Furthermore, as shown in Figure 8F, in Example 4, even though the Ti content was as low as 0.94 mass%, the presence of 5.08 mass% Nb allowed for the crystallization of MC carbide 32, and the amount of free carbon 31 was also reduced. On the other hand, as shown in Figure 8B, in Comparative Example 2, which used a non-cermet portion containing 15.0 mass% or more Ti, a small amount of M6C carbide 30 was observed in the intermediate layer in addition to MC carbide 32.

[0084] Table 3 below shows the thickness of the intermediate layer for Examples 1 to 4, Comparative Example 1, and Comparative Example 2. Table 3 also shows the area ratio of M6C carbides in the intermediate layer for Examples 1 to 4, Comparative Example 1, and Comparative Example 2. The area ratio of M6C carbides was calculated using the EBSD method, scanning a 200 μm × 200 μm area in 0.7 μm steps in the central part of the intermediate layer of the cross-section of the cermet composite material along the lamination direction, and was calculated as the percentage of the area of ​​M6C carbides observed on the measurement screen.

[0085] Furthermore, Table 3 below shows the area ratios of free carbon, MC carbides, and tungsten carbides in the intermediate layers of Examples 1 to 4, Comparative Example 1, and Comparative Example 2. The area ratios of free carbon, MC carbides, and tungsten carbides were calculated by binarizing BSE images acquired at a magnification of 1000x.

[0086] In Table 3 below, for structural evaluation, a sample was rated "Excellent" if the area ratio of M6C carbides was 20% or less and the area ratio of free carbon was 1% or less; "Good" if either of the following conditions was met; and "Poor" if neither condition was met.

[0087] As described above, in considering cermet composite materials that can improve bonding strength, we investigated how to increase the toughness of the intermediate layer. Focusing on the combination of cermet and non-cermet parts, we conducted further studies and confirmed that by selecting a Ni-based alloy containing 3.0% to 15.0% by mass of Ti for the non-cermet part, or, if the Ti content is 0.5% to less than 3.0% by mass, a Ni-based alloy containing a total of 4% to 15% by mass of Nb and Ta in addition to Ti, it is possible to form an intermediate layer containing the components of the cermet and non-cermet parts with low amounts of M6C carbides and free carbon, resulting in an intermediate layer with excellent crack resistance.

[0088] [Table 3]

[0089] To observe the intermediate layer in detail as shown in Example 4, microstructural observation was performed using a transmission electron microscope (TEM) and a scanning transmission electron microscope (STEM).

[0090] Figure 9A shows a TEM image of the crystal structure in the intermediate layer of Example 4, and Figure 9B shows the results of elemental mapping of the crystal structure in the intermediate layer of Example 4 by energy dispersive X-ray spectroscopy (EDX). Figures 9C-G show the results of limited-field electron diffraction of phases 50-54 observed in Figures 9A and 9B. Limited-field electron diffraction reveals diffraction patterns corresponding to the crystal structure of each phase, and the crystal structure can be identified by analyzing the distance and angle of these diffraction patterns. Analysis of the limited-field electron diffraction patterns revealed that phase 50, which is concentrated with dendritic W, is M 12 It was found to be a C carbide. 12 The C carbide is a carbide with a crystal structure and properties very similar to M6C carbide. Furthermore, the Cr-enriched phase 51 was found to be a brittle intermetallic compound σ phase. In addition, the matrix phase 52 was found to be a face-centered cubic (FCC) lattice, with fine W2C carbides 53 dispersed within it. Furthermore, the Ti and Nb-enriched phase 54 was found to be an MC carbide.

[0091] The area ratio of the σ phase can be calculated by image processing of the Cr elemental mapping image. Therefore, EDX elemental mapping was performed on the intermediate layer shown in Example 4 at a magnification of 300x, and the area ratio of the σ phase was calculated to be 8.3%.

[0092] Although embodiments have been described above using drawings and other visual aids, the present invention is not limited to these embodiments. Any configuration that is substantially identical to the technical idea described in the claims of the present invention and achieves similar effects is included within the technical scope of the present invention and includes various modifications. For example, the embodiments are described in detail to make the present invention easier to understand and are not necessarily limited to those having all the described configurations. Furthermore, it is possible to replace parts of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add configurations from other embodiments to the configuration of one embodiment. In addition, it is possible to add, delete, or replace parts of the configuration of each embodiment with other configurations. [Explanation of Symbols]

[0093] 1. Cermet part 2 Non-cermet part 3. Middle Class 4. Hard coating layer 5 Poor fusion 10 Cermet composite materials 20 Cermet Tools 21 Processing Department 22 Base 30 M6C carbides 31 Free carbon 32 MC carbide 33 Tungsten Carbide 40 Cermet Tools 41 Processing Department 42 Lower layer 43 Base body 50 M 12 C carbide 51 σ phase 52 FCC 53 W2C Carbide 54 MC carbide S1 Preheating process S2 Composite material manufacturing process S3 Heat treatment process S10 Method for manufacturing cermet composite materials All publications, patents, and patent applications cited herein shall be incorporated herein by direct reference.

Claims

1. A cermet composite material having a cermet portion in which hard carbides are dispersed in a metallic phase, and a non-cermet portion made of a Ni-based alloy containing 50% by mass or more of Ni, wherein the cermet portion is laminated on the non-cermet portion, Between the cermet portion and the non-cermet portion, there is an intermediate layer in which the components of the cermet portion and the components of the non-cermet portion are mixed. The non-cermet portion is made of the Ni-based alloy containing 10.0% by mass or more and 15.0% by mass or less Ti, or the Ni-based alloy containing 0.5% by mass or more and less than 3.0% by mass Ti, and a total of 4% by mass or more and 15% by mass or less Nb and Ta. If the non-cermet portion is made of the Ni-based alloy containing 10.0% by mass or more and 15.0% by mass or less of Ti, the hard carbide includes any of tungsten carbide (WC), niobium carbide (NbC), tantalum carbide (TaC), molybdenum carbide (MoC), and vanadium carbide (VC). If the non-cermet portion is made of the Ni-based alloy containing a total of 4% by mass or more and 15% by mass or less of Nb and Ta, the hard carbide includes any of tungsten carbide (WC), molybdenum carbide (MoC), and vanadium carbide (VC). The intermediate layer M ６ A cermet composite material characterized by having a surface area ratio of C carbide of 24% or less.

2. The cermet composite material according to claim 1, characterized in that the intermediate layer contains dispersed carbide particles.

3. The cermet composite material according to claim 2, characterized in that the carbide particles include at least one of MC carbide and tungsten carbide.

4. The cermet composite material according to claim 2, characterized in that the carbide particles include MC carbide, and the area ratio of the MC carbide is 3% to 24%.

5. The cermet composite material according to any one of claims 1 to 4, characterized in that the thickness of the intermediate layer is 500 μm or more.

6. The cermet composite material according to any one of claims 1 to 5, characterized in that when the X-ray count of the constituent elements of the hard carbide in the cermet portion is measured by an electron beam microanalyzer, the X-ray count decreases from the cermet portion side toward the non-cermet portion side.

7. The cermet composite material according to any one of claims 1 to 6, characterized in that the cermet portion contains at least one of Co, Ni, and Fe in an amount of 20% by mass or more and 50% by mass or less, with the remainder being a hard carbide.

8. The cermet composite material according to claim 7, characterized in that the cermet portion is made of a WC-Co cemented carbide alloy containing 20% ​​by mass or more and 50% by mass or less of Co, with the remainder being tungsten carbide.

9. The cermet composite material according to any one of claims 1 to 8, characterized in that the non-cermet portion contains 19.0% by mass or less of Cr and 25.0% by mass or less of Fe, and the area ratio of the intermetallic compound including the σ phase and Laves phase in the intermediate layer is 8% or less.

10. The cermet composite material according to any one of claims 1 to 9, further comprising a hard coating layer provided on the surface of the cermet portion, comprising at least one carbide, nitride, oxide, or carbonitride from the group consisting of Ti, Al, and Cr.

11. It has a cermet portion in which hard carbides are dispersed in a metallic phase, and a non-cermet portion made of a Ni-based alloy containing 50% by mass or more of Ni and 10.0% by mass or more of Ti and 15.0% by mass or less, or a Ni-based alloy containing 50% by mass or more of Ni, 0.5% by mass or more of Ti and a total of 4% by mass or more of Nb and Ta and 15% by mass or less. A method for manufacturing a cermet composite material, wherein the non-cermet portion is made of the Ni-based alloy containing 10.0% by mass or more and 15.0% by mass or less of Ti, and the hard carbide contains any of tungsten carbide (WC), niobium carbide (NbC), tantalum carbide (TaC), molybdenum carbide (MoC), and vanadium carbide (VC), and the non-cermet portion is made of the Ni-based alloy containing a total of 4% by mass or more and 15% by mass or less of Nb and Ta, and the hard carbide contains any of tungsten carbide (WC), molybdenum carbide (MoC), and vanadium carbide (VC), A preheating step in which the non-cermet part is preheated to a temperature of 350°C to 800°C, The process includes a composite material manufacturing step of forming a cermet portion on the non-cermet portion by additive manufacturing, thereby producing a cermet composite material having an intermediate layer between the non-cermet portion and the cermet portion in which the components of the non-cermet portion and the components of the cermet portion are mixed. The intermediate layer M ６ A method for producing a cermet composite material, characterized in that the area ratio of C carbide is 24% or less.

12. The method for manufacturing a cermet composite material according to claim 11, characterized in that, in the preheating step, the non-cermet portion is preheated to a temperature of 500°C or more and 800°C or less.

13. The method for manufacturing a cermet composite material according to claim 11 or 12, further comprising a heat treatment step of heat-treating the cermet composite material at a temperature of 1000°C to 1300°C after the composite material manufacturing step.

14. The method for manufacturing a cermet composite material according to claim 13, characterized in that the cermet composite material is heat-treated at a temperature of 1200°C or higher and 1300°C or lower in the heat treatment step.

15. A cermet tool using a cermet composite material according to any one of claims 1 to 10, It has a machining section for processing a workpiece and a base for supporting the machining section, A cermet tool characterized in that the processed portion is the cermet portion, and the processed portion side of the base is the non-cermet portion.

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