A high-temperature alloy-ti(c,n) cermet material and a method of making the same

Abstract

The present application relates to a kind of high-temperature alloy-Ti (C, N) composite cermet material and its preparation method, belong to metallurgical technology field.The preparation method of the present application includes the following steps: S1, high-temperature alloy powder and Ti (C, N) ceramic powder are dry ground, ultrasonic dispersion, wet grinding and drying, obtain cermet powder;S2, cermet powder is two-way pressed, vacuum sintering and cooling, obtain high-temperature alloy-Ti (C, N) composite cermet material.The high-temperature alloy-Ti (C, N) composite cermet material prepared by the method has excellent high hardness, strong toughness and high-temperature resistant characteristics, the mechanical properties at room temperature and high temperature are outstanding, can meet the stringent requirements of extreme working conditions and high-speed cutting on the comprehensive performance of material.

Description

Technical Field

[0001] This invention belongs to the field of metallurgical technology, and particularly relates to a high-temperature alloy-Ti(C,N) composite metal ceramic material and its preparation method. Background Technology

[0002] As the global high-end manufacturing industry transforms towards higher precision and intelligence, the aerospace, automotive, and precision machinery manufacturing sectors are placing higher demands on the comprehensive performance of materials. Ti(C,N)-based cermets, with their advantages brought by compositional microstructure and interfacial characteristics, exhibit superior wear resistance, high-temperature oxidation resistance, and chemical stability compared to traditional WC-Co cemented carbides.

[0003] However, the industrialization of this type of cermet is still significantly lagging behind, mainly due to three reasons: First, its market share in the cutting tool industry, its main application area, is relatively small; second, the strength-toughness inversion effect is prominent, with the strength and toughness of Ti(C,N)-based cermets decreasing significantly with increasing hardness compared to traditional cemented carbides; and third, its high-temperature service performance is insufficient. The service temperatures and operating conditions in the aerospace and automotive fields are becoming increasingly stringent, and the precision requirements for machined parts are continuously increasing. Ti(C,N)-based cermets used in high-temperature components are required to have a temperature resistance of no less than 1100℃, while Ti(C,N)-based cermet tools used for high-speed cutting at instantaneous temperatures exceeding 1200℃ require even better high-temperature hardness and strength, otherwise material failure is likely. Therefore, how to prepare Ti(C,N)-based cermet materials with both excellent strength, toughness, and high-temperature performance while maintaining high hardness to meet the needs of use under extreme operating conditions and high-speed cutting conditions presents a significant scientific challenge and research value.

[0004] Comprehensive research indicates that to obtain Ti(C,N)-based cermets possessing high hardness, toughness, and excellent high-temperature performance, precise control of composition and processing is required, along with enhancing the characteristics of the hard and binder phases and the interfacial bonding strength. Currently, high-entropy binding of the binder phase has shown significant effects in improving the toughness and high-temperature performance of Ti(C,N)-based cermets; however, this technology suffers from high preparation costs, complex processes, and a lack of comprehensive performance data and long-term application experience, posing significant challenges to its industrial-scale promotion.

[0005] Other studies have shown that introducing ceramic phases into the matrix of high-temperature alloys can combine the plasticity of high-temperature alloys with the high strength, hardness, wear resistance and corrosion resistance of ceramics, which can significantly extend the service life of particle-reinforced high-temperature alloy composites in extreme environments. However, there are few studies on the composite of high-temperature alloys and ceramics, and most of them are prepared by additive manufacturing, resulting in low density of the prepared samples. Even if the ceramic phase accounts for no more than 10 wt%, it still proves the feasibility of the two-phase composite. Among them, patent CN117983834A discloses a method for preparing high-performance nickel-based superalloy / ceramic composite materials using laser powder bed melting technology. By mixing ceramic powder and nickel-based superalloy powder and performing laser powder bed melting, the resulting composite material has refined grains and simultaneously improved strength and hardness. However, because the ceramic phase content does not exceed 10wt%, it cannot meet the hardness requirements of cutting tools. Patent CN112522564A discloses a method for preparing TiB2 particle-reinforced nickel-based superalloy. TiB2 is added to the molten alloy, kept at a constant temperature, and then cast, which achieves grain refinement and reduction of dendrite spacing. However, this method is too complex and has serious interdendritic segregation problems. HM Zhang et al. prepared TiC / Inconel 718 composite materials using selective laser cladding technology. After forming, the sample had a large number of small pores, insufficient density, and low performance improvement and forming quality.

[0006] Existing research focuses on high-temperature alloys as the matrix, with the addition of ceramic phases to improve their mechanical properties. The proportion of ceramic phases added is generally low. Although cermets and high-temperature alloys are widely used in their respective fields, research on Ti(C,N) and high-temperature alloy composites with high ceramic content is still lacking. There are almost no studies on using ceramic phases as the main phase and high-temperature alloy phases as the binder phase to prepare high-hardness, high-strength and high-toughness tool materials. This is mainly because in cermet systems, the proportion of ceramic phases can reach up to 85 vol%, and the mass percentage is also relatively high, which is exactly the opposite of the ratio of ceramic particle-reinforced high-temperature alloy composites.

[0007] Therefore, the preparation of high-density composite metal-ceramic materials with excellent room-temperature and high-temperature performance is crucial for the application of high-temperature alloy-Ti(C,N) composite metal-ceramics. Summary of the Invention

[0008] Therefore, the technical problem to be solved by the present invention is to overcome the problems of low high-temperature mechanical properties and short service life of metal ceramic materials under high-speed cutting conditions in the prior art.

[0009] To address the aforementioned technical problems, this invention provides a high-temperature alloy-Ti(C,N) composite cermet material and its preparation method. The high-temperature alloy-Ti(C,N) composite cermet material prepared by this method possesses excellent high hardness, toughness, and high-temperature resistance, exhibiting outstanding mechanical properties at both room temperature and high temperature. It can meet the stringent requirements for the comprehensive performance of materials under extreme working conditions and high-speed cutting.

[0010] The first objective of this invention is to provide a method for preparing a high-temperature alloy-Ti(C,N) composite cermet material, comprising the following steps:

[0011] S1. High-temperature alloy powder and Ti(C,N) ceramic powder are subjected to dry grinding, ultrasonic dispersion, wet grinding and drying to obtain metal-ceramic powder;

[0012] S2. The metal-ceramic powder described in S1 is subjected to bidirectional pressing, vacuum sintering and cooling to obtain the high-temperature alloy-Ti(C,N) composite metal-ceramic material.

[0013] In one embodiment of the present invention, in S1, the high-temperature alloy powder is GH3625 high-temperature alloy with a particle size of 15μm-25μm;

[0014] And / or, the particle size of the Ti(C,N) ceramic powder is 0.5μm-2μm;

[0015] And / or, the mass ratio of the high-temperature alloy powder to the Ti(C,N) ceramic powder is 1:(1-4).

[0016] In one embodiment of the present invention, in S1, the process parameters of the dry grinding are as follows: the grinding media is cemented carbide balls, the ball-to-material ratio is (3-6):1, the grinding speed is 100rpm-200rpm, the grinding time is 2h-6h, and the air pressure is 0.3atm-0.5atm. This process is designed for the controlled grinding of coarse high-temperature alloy powder and fine Ti(C,N) ceramic powder with significant differences in particle size. It not only effectively overcomes the problems of insufficient uniformity and easy introduction of contamination in this type of heterogeneous powder system caused by simple mechanical stirring, but also successfully solves the problems of fine powder agglomeration and gravity / inertial segregation. While breaking the agglomeration of Ti(C,N) fine particles and promoting their initial uniform adhesion to the surface of high-temperature alloy particles, it precisely avoids the excessive refinement of high-temperature alloy powder, cold work hardening, and severe breakage of Ti(C,N) particles. This lays a key foundation for the preparation of high-temperature alloy-Ti(C,N) composite metal ceramic materials with uniform structure and high performance.

[0017] In one embodiment of the present invention, in S1, during the ultrasonic dispersion process, 1.2-1.8 times the total weight of the raw materials of ethanol and 1wt%-3wt% of the total weight of the raw materials of polyethylene glycol solution are added; the concentration of the polyethylene glycol solution is 0.4mol / L-0.6mol / L; this process aims to solve the problem that submicron-level agglomeration or incompletely dissociated soft agglomerates may still exist in fine Ti(C,N) powder after dry grinding. By using the synergistic effect of ethanol-PEG-ultrasound, the macroscopic physical dispersion limit of dry grinding is broken through, and Ti(C,N) nano / submicron particles are uniformly dispersed at the particle size in coarse high-temperature alloy particles, minimizing local enrichment areas; wherein ethanol acts as a low-polarity dispersant. The medium, with its strong permeability, can fully wet the powder surface and weaken the van der Waals forces between particles. The introduction of PEG enables the slurry to form a weak gel network structure, significantly improving the anti-settling ability of Ti(C,N) powder and ensuring the stability of the mixed slurry during transportation and molding to avoid gravity segregation. Ultrasonic dispersion of liquid slurry can accurately dissociate Ti(C,N) residual agglomerates without damaging the morphology of high-temperature alloy particles and the Ti(C,N) adhesion structure. Moreover, the high-stability slurry output by this process can be directly connected to subsequent wet grinding and molding processes, forming an integrated technical route of "dry mixing-wet dispersion-wet mixing-molding", which greatly shortens the process flow and avoids interface contamination caused by secondary processing.

[0018] In one embodiment of the present invention, in S1, the process parameters of the wet milling are as follows: the milling medium is cemented carbide balls, the ball-to-material ratio is (4-8):1, the milling speed is 220rpm-350rpm, and the milling time is 12h-24h.

[0019] In one embodiment of the present invention, in S1, the drying is carried out using an infrared drying oven at 70°C-85°C.

[0020] In one embodiment of the present invention, in S2, the pressure of the bidirectional compression is 180MPa-300MPa.

[0021] In one embodiment of the present invention, in S2, the vacuum sintering is divided into three stages:

[0022] The first stage involves heating to 700℃-1000℃ at a rate of 0.2℃ / min-0.4℃ / min and holding at that temperature for 1-3 hours. This slow heating combined with prolonged holding aims to completely remove residual PEG and ethanol from the raw materials, achieving degumming without cracking, thus avoiding carbon contamination, preventing embrittlement of the high-temperature alloy, and ultimately ensuring that the carbon increment is ≤0.01%.

[0023] The second stage involves heating to 1100℃-1300℃ at a rate of 0.5℃ / min-1℃ / min and holding for 2h-4h. This stage mainly involves solid-phase heating and holding. The long holding time promotes the full dissolution of the solid solution strengthening phase in the high-temperature alloy and initially achieves a combination with the Ti(C,N) phase, thereby constructing a strong and toughened interface and effectively improving the compatibility between the ceramic phase and the metal phase.

[0024] The third stage involves heating to 1400℃-1500℃ at a rate of 1℃ / min-2℃ / min and holding at that temperature for 0.5h-2h. This stage is the final liquid-phase sintering and holding stage, primarily achieving densification sintering while ensuring uniform dispersion of Ti(C,N) particles and suppressing abnormal grain growth. Since the entire vacuum sintering process is conducted at a vacuum level higher than 1.0×10⁻⁶, the temperature remains constant throughout the process. -2 The process is carried out under the Pa environment, which not only ensures that the oxidation weight loss rate of alloying elements is <0.05%, but also effectively inhibits the high-temperature decomposition of Ti(C,N).

[0025] In one embodiment of the present invention, in S2, the cooling is first performed by introducing flowing Ar gas at 0.5 atm-0.8 atm to cool to 190°C-210°C, and then cooling with the furnace. This rapid cooling in this stage can quickly cross the sensitive zone of carbide precipitation in the high-temperature alloy, avoid the aggregation of brittle phase along the grain boundary, and at the same time inhibit the continued growth of the ceramic hard phase, significantly refine the ceramic phase grains, and thus effectively improve the comprehensive mechanical properties of the material.

[0026] A second objective of this invention is to provide a high-temperature alloy-Ti(C,N) composite cermet material prepared by the method described above, wherein the elemental composition and mass percentage of the high-temperature alloy-Ti(C,N) composite cermet material are as follows: Ti 32.53%-51.89%, Ni 12.27%-30.68%, Cr 4.25%-10.63%, Mo 1.90%-4.75%, Fe 0.69%-1.73%, Nb 0.75%-1.87%, Al 0.07%-0.18%, Co 0.01%-0.02%, Cu 0.01%-0.03%, C 8.14%-13.00%, and N 9.48%-15.16%.

[0027] The technical solution of the present invention has the following advantages compared with the prior art:

[0028] (1) The preparation method described in this invention first breaks up the agglomeration of Ti(C,N) fine particles by dry ball milling and promotes their initial uniform adhesion to the surface of high-temperature alloy particles to form interatomic bonds. Then, the interface reaction is controlled by a precisely controlled vacuum sintering process. This not only achieves a tight bond between the high-temperature alloy matrix and the Ti(C,N) ceramic phase, but also promotes the formation of a weak core / coreless structure in the core region of the hard phase due to element interdiffusion. This structure can significantly reduce the interfacial stress between the two phases and improve the strength and toughness. At the same time, the Ti(C,N) particles are uniformly dispersed in the high-temperature alloy matrix as hard points to hinder dislocation movement. Combined with the excellent high-temperature stability of the γ' phase in the high-temperature alloy matrix, the material has both excellent room temperature and high-temperature mechanical properties. In addition, the Ni-Cr matrix of the high-temperature alloy can form a dense Cr2O3 oxide film to prevent further oxidation. The Ti(C,N) particles remain stable at high temperatures and do not soften or decompose. The two work together to maintain the high-temperature strength of the material, and finally achieve a simultaneous leap in the strength and toughness of the material at room temperature and high temperature.

[0029] (2) The high-temperature alloy and Ti(C,N) used in the preparation method of the present invention have significantly different coefficients of thermal expansion, which easily generate interfacial stress during the sintering and cooling process, leading to cracking or debonding problems. Traditional sintering methods cannot effectively control the interfacial reaction, which easily forms brittle phases and reduces the bonding strength. At the same time, conventional powder metallurgy methods require high-temperature and long-term sintering, which will cause high-temperature alloy grain growth, Ti(C,N) particle coarsening and compositional segregation, making it difficult to achieve uniform composite of the two. The present invention uses a synergistic dispersion process of dry ball milling and ethanol-PEG-ultrasound to process coarse high-temperature alloy powder and fine Ti(C,N) powder. It achieves cross-scale uniform mixing without damaging the characteristics of the raw material powder, reducing fine powder agglomeration and segregation, oxidation pollution of high-temperature alloy powder and powder damage. It not only lays the raw material foundation for sintering to prepare high-homogeneity high-temperature alloy-Ti(C,N) composite metal ceramic materials with weak core / coreless structure, but also significantly shortens the process flow and avoids interfacial pollution caused by secondary processing. At the same time, the segmented vacuum sintering process effectively suppresses the problem of abnormal grain growth during sintering, and finally achieves the homogenization of material structure.

[0030] (3) The preparation method described in this invention is simple and the entire preparation process can be completed with only one thermal cycle. No special production equipment is required. Ordinary vacuum sintering furnace can meet the production requirements, which effectively reduces the production cost and is conducive to industrial promotion and application. Attached Figure Description

[0031] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein:

[0032] Figure 1This is a SEM image of the high-temperature alloy-Ti(C,N) composite metal ceramic material prepared in Example 4 of this invention;

[0033] Figure 2 This is a SEM image of the high-temperature alloy-Ti(C,N) composite metal ceramic material prepared in Example 6 of the present invention;

[0034] Figure 3 This is a SEM image of the high-temperature alloy-Ti(C,N) composite metal ceramic material prepared in Example 7 of the present invention;

[0035] Figure 4 This is a SEM image of the high-temperature alloy-Ti(C,N) composite metal ceramic material prepared in Example 9 of the present invention. Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0037] In this invention, unless otherwise stated, the particle size of the GH3625 high-temperature alloy powder used in the embodiments of this invention is approximately 15μm-25μm.

[0038] In this invention, unless otherwise stated, the particle size of the Ti(C,N) ceramic powder used in the embodiments of this invention is approximately 0.5 μm-2 μm.

[0039] In this invention, unless otherwise stated, the concentration of the PEG solution used in the embodiments of this invention is 0.5 mol / L, and the molecular weight of PEG is 2000.

[0040] In this invention, unless otherwise stated, the bidirectional pressing device used in the embodiments of this invention is a DY-30 tabletop electric tablet press.

[0041] Example 1

[0042] The high-temperature alloy-Ti(C,N) composite metal-ceramic material and its preparation method in this embodiment specifically include the following steps:

[0043] S1. Preparation of the mixture: GH3625 high-temperature alloy powder and Ti(C,N) ceramic powder were coarsely mixed at a mass ratio of 5:5 (total mass percentages: Ti 32.53%, Ni 30.68%, Cr 10.63%, Mo 4.75%, Fe 1.73%, Nb 1.83%, Al 0.18%, Co 0.02%, Cu 0.03%, C 8.14%, N 9.48%), and then dry-milled in a planetary ball mill. The milling media were cemented carbide balls, the ball-to-powder ratio was 6:1, the milling speed was 100 rpm, and the milling time was 2 hours. The entire process was carried out under an Ar atmosphere, and the gas pressure inside the milling jar was 0.3 atm, resulting in a mixed powder.

[0044] S2. Preparation of metal-ceramic powder: 1.2 times the weight of anhydrous ethanol and 3 wt% PEG solution were added to the mixed powder to form a slurry. The slurry was then ultrasonically dispersed for 6 hours. Subsequently, the slurry was wet-milled in a planetary ball mill with cemented carbide balls as the milling media, a ball-to-powder ratio of 4:1, a milling speed of 350 rpm, and a milling time of 12 hours. The milled metal-ceramic slurry was then placed in a far-infrared drying oven for atmospheric pressure drying at 85°C to obtain metal-ceramic powder.

[0045] S3. Preparation of high-temperature alloy-Ti(C,N) composite cermet material: The cermet powder was pressed into shape using biaxial pressing at a pressure of 180 MPa; subsequently, vacuum sintering was performed in a vacuum / atmosphere integrated furnace, with the entire sintering process conducted at a vacuum level higher than 1.0 × 10⁻⁶. -2 The process was carried out under the conditions of Pa, specifically divided into three stages: the first stage was to heat up to 700℃ at a rate of 0.4℃ / min and hold for 1h; the second stage was to heat up to 1300℃ at a rate of 0.5℃ / min and hold for 4h; and the third stage was to heat up to 1400℃ at a rate of 2℃ / min and hold for 0.5h. After vacuum sintering, 0.8 atm of flowing Ar gas was introduced into the sintering furnace, and after cooling to 200℃, it was cooled to room temperature with the furnace to obtain the high-temperature alloy-Ti(C,N) composite metal ceramic material.

[0046] Example 2

[0047] The process is basically the same as in Example 1, except that GH3625 high-temperature alloy powder and Ti(C,N) ceramic powder are coarsely mixed at a mass ratio of 4:6 (total mass percentages: Ti 38.99%, Ni 24.54%, Cr 8.50%, Mo 3.80%, Fe 1.38%, Nb 1.49%, Al 0.14%, Co 0.01%, Cu 0.02%, C 9.76%, N 11.37%).

[0048] Example 3

[0049] The process is basically the same as in Example 1, except that: GH3625 high-temperature alloy powder and Ti(C,N) ceramic powder are coarsely mixed at a mass ratio of 3:7 (total mass percentages: Ti 45.45%, Ni 18.41%, Cr 6.38%, Mo 2.85%, Fe 1.00%, Nb 1.12%, Al 0.11%, Co 0.01%, Cu 0.02%, C 11.38%, N 13.27%).

[0050] Example 4

[0051] The process is basically the same as in Example 1, except that GH3625 high-temperature alloy powder and Ti(C,N) ceramic powder are coarsely mixed at a mass ratio of 2:8 (total mass percentages: Ti 51.89%, Ni 12.27%, Cr 4.25%, Mo 1.90%, Fe 0.69%, Nb 0.75%, Al 0.07%, Co 0.01%, Cu 0.01%, C 13.00%, N 15.16%).

[0052] Example 5

[0053] The process is basically the same as in Example 1, except that the preparation method is different, specifically including the following steps:

[0054] S1. Preparation of the mixture: After coarsely mixing GH3625 high-temperature alloy powder and Ti(C,N) ceramic powder, it is placed in a planetary ball mill for dry grinding. The grinding media is cemented carbide balls, the ball-to-material ratio is 3:1, the ball milling speed is 150 rpm, the ball milling time is 6 hours, and the whole process is carried out under Ar atmosphere. The gas pressure in the ball mill jar is 0.5 atm to obtain mixed powder.

[0055] S2. Preparation of metal-ceramic powder: 1.8 times the weight of anhydrous ethanol and 1 wt% PEG solution were added to the mixed powder to form a slurry, which was then ultrasonically dispersed for 2 hours. Subsequently, the slurry was placed in a planetary ball mill for wet milling. The milling media were cemented carbide balls, the ball-to-powder ratio was 8:1, the milling speed was 220 rpm, and the milling time was 24 hours. The milled metal-ceramic slurry was then placed in a far-infrared drying oven for atmospheric pressure drying at 70℃ to obtain metal-ceramic powder.

[0056] S3. Preparation of high-temperature alloy-Ti(C,N) composite cermet material: The cermet powder was pressed into shape using biaxial pressing at a pressure of 300 MPa; subsequently, vacuum sintering was performed in a vacuum / atmosphere integrated furnace, with the entire sintering process conducted at a vacuum level higher than 1.0 × 10⁻⁶. -2The process was carried out under the conditions of Pa, specifically divided into three stages: the first stage was to heat up to 1000℃ at a rate of 0.2℃ / min and hold for 3h; the second stage was to heat up to 1100℃ at a rate of 1℃ / min and hold for 2h; and the third stage was to heat up to 1500℃ at a rate of 1℃ / min and hold for 2h. After vacuum sintering, 0.5 atm of flowing Ar gas was introduced into the sintering furnace. After cooling to 200℃, the furnace was cooled to room temperature to obtain the high-temperature alloy-Ti(C,N) composite metal ceramic material.

[0057] Example 6

[0058] The basic structure is the same as in Example 5, except that the mass ratio of GH3625 high-temperature alloy powder to Ti(C,N) ceramic powder is the same as in Example 2.

[0059] Example 7

[0060] The basic structure is the same as in Example 5, except that the mass ratio of GH3625 high-temperature alloy powder to Ti(C,N) ceramic powder is the same as in Example 3.

[0061] Example 8

[0062] The basic structure is the same as in Example 5, except that the mass ratio of GH3625 high-temperature alloy powder to Ti(C,N) ceramic powder is the same as in Example 4.

[0063] Example 9

[0064] The process is basically the same as in Example 1, except that the preparation method is different, specifically including the following steps:

[0065] S1. Preparation of the mixture: After coarsely mixing GH3625 high-temperature alloy powder and Ti(C,N) ceramic powder, the mixture is placed in a planetary ball mill for dry grinding. The grinding media is cemented carbide balls, the ball-to-material ratio is 4:1, the ball milling speed is 200 rpm, the ball milling time is 4 h, and the entire process is carried out under an Ar atmosphere with a gas pressure of 0.4 atm in the ball mill jar to obtain the mixed powder.

[0066] S2. Preparation of metal-ceramic powder: 1.5 times the weight of anhydrous ethanol and 2wt% PEG solution were added to the mixed powder to form a slurry, which was then ultrasonically dispersed for 4 hours. Subsequently, the slurry was placed in a planetary ball mill for wet milling. The milling media were cemented carbide balls, the ball-to-powder ratio was 6:1, the milling speed was 280 rpm, and the milling time was 18 hours. The milled metal-ceramic slurry was then placed in a far-infrared drying oven for atmospheric pressure drying at 80℃ to obtain metal-ceramic powder.

[0067] S3. Preparation of high-temperature alloy-Ti(C,N) composite cermet material: The cermet powder was pressed into shape using biaxial pressing at a pressure of 240 MPa; subsequently, vacuum sintering was performed in a vacuum / atmosphere integrated furnace, with the entire sintering process conducted at a vacuum level higher than 1.0 × 10⁻⁶. -2 The process was carried out under the conditions of Pa, specifically divided into three stages: the first stage was to heat up to 800℃ at a rate of 0.3℃ / min and hold for 2h; the second stage was to heat up to 1200℃ at a rate of 0.8℃ / min and hold for 3h; and the third stage was to heat up to 1450℃ at a rate of 1.5℃ / min and hold for 1h. After vacuum sintering, 0.6 atm of flowing Ar gas was introduced into the sintering furnace, and after cooling to 200℃, it was cooled to room temperature with the furnace to obtain the high-temperature alloy-Ti(C,N) composite metal ceramic material.

[0068] Example 10

[0069] The basic structure is the same as in Example 9, except that the mass ratio of GH3625 high-temperature alloy powder to Ti(C,N) ceramic powder is the same as in Example 2.

[0070] Example 11

[0071] The basic structure is the same as in Example 9, except that the mass ratio of GH3625 high-temperature alloy powder to Ti(C,N) ceramic powder is the same as in Example 3.

[0072] Example 12

[0073] The basic structure is the same as in Example 9, except that the mass ratio of GH3625 high-temperature alloy powder to Ti(C,N) ceramic powder is the same as in Example 4.

[0074] Comparative Example 1

[0075] The comparative example of the metal-ceramic material and its preparation method specifically includes the following steps:

[0076] S1. Preparation of the mixture: Ni powder, Mo powder, C powder, Ti(C,N) ceramic powder, etc., are coarsely mixed according to the following mass percentages: Ti 32.07%, Ni 31.09%, Cr 9.93%, Mo 5.1%, Fe 0.6%, Nb 1.03%, Al 0.00%, Co 0.00%, Cu 0.00%, C 10.35%, and N 9.83%. The mixture is then placed in a nylon can, and cemented carbide balls are added as the milling media at a ball-to-material ratio of 6:1. An appropriate amount of anhydrous ethanol is added at a liquid-to-material ratio of 2:1. The slurry in the can is then manually pre-stirred before starting the ball mill at 260 rpm for 24 hours. The milled metal-ceramic slurry is then placed in a far-infrared drying oven for atmospheric pressure drying at 85℃ to obtain metal-ceramic powder.

[0077] S3. Preparation of cermet materials: The cermet powder was pressed into shape using biaxial pressing. The first pressing pressure was 130 MPa, and the holding time was 60 s; the second pressing pressure was 80% of the first pressure, and the holding time was 30 s; subsequently, vacuum sintering was carried out in a vacuum / atmosphere integrated furnace, with the entire sintering process conducted at a vacuum level higher than 1.0 × 10⁻⁶. -2 The process was carried out under the conditions of Pa, specifically divided into four stages: the first stage involved heating to 400℃ at a rate of 0.5℃ / min and holding for 30 min; the second stage involved heating to 600℃ at a rate of 0.5℃ / min and holding for 30 min; the third stage involved heating to 800℃ at a rate of 0.5℃ / min and holding for 30 min; and the fourth stage involved heating to 1450℃ at a rate of 2℃ / min and holding for 1 h. After vacuum sintering, the material was cooled to room temperature in the furnace to obtain the metal-ceramic material.

[0078] Comparative Example 2

[0079] The composition is basically the same as Comparative Example 1, except that the mass percentages are as follows: Ti 39.26%, Ni 25.15%, Cr 8.15%, Mo 4.25%, Fe 0.32%, Nb 0.87%, Al 0.00%, Co 0.00%, Cu 0.00%, C 10.72%, and N 11.28%.

[0080] Comparative Example 3

[0081] The composition is basically the same as Comparative Example 1, except that the mass percentages are: Ti 44.73%, Ni 18.33%, Cr 6.22%, Mo 2.78%, Fe 0.15%, Nb 0.55%, Al 0.00%, Co 0.00%, Cu 0.00%, C 12.56%, and N 14.68%.

[0082] Comparative Example 4

[0083] The composition is basically the same as Comparative Example 1, except that the mass percentages are as follows: Ti 53.15%, Ni 11.26%, Cr 4.06%, Mo 1.22%, Fe 0.08%, Nb 0.32%, Al 0.00%, Co 0.00%, Cu 0.00%, C 14.35%, and N 15.56%.

[0084] Comparative Example 5

[0085] The process is basically the same as in Example 1, except that GH3625 high-temperature alloy powder and Ti(C,N) ceramic powder are coarsely mixed at a mass ratio of 6:4.

[0086] The sintering process fails to achieve the desired shape, resulting in a soft and collapsed appearance.

[0087] Comparative Example 6

[0088] The process is basically the same as in Example 1, except that GH3625 high-temperature alloy powder and Ti(C,N) ceramic powder are coarsely mixed at a mass ratio of 1:9.

[0089] The surface of the obtained metal-ceramic material showed obvious pores and cracks.

[0090] Test Example 1

[0091] The high-temperature alloy-Ti(C,N) composite cermet materials prepared in Examples 4, 6, 7, and 9 were characterized, and the results are as follows: Figures 1-4 As shown. From Figures 1-4 It can be seen that the microstructure of the high-temperature alloy-Ti(C,N) composite cermet material consists of Ti(C,N) hard phase particles with a weak core / coreless structure and a GH3625 high-temperature alloy binder phase. This weak core / coreless structure can significantly reduce the interfacial stress between the hard phase and the binder phase, making the two phases bond more tightly. When fractured under external force, more energy is consumed, thus effectively improving the strength and toughness of the material. At the same time, the γ' phase in the GH3625 high-temperature alloy matrix has excellent high-temperature stability. The synergistic effect of this characteristic and the weak core / coreless structure ultimately makes the composite cermet not only have excellent high-temperature mechanical properties, but also maintain good room-temperature mechanical properties.

[0092] Test Example 2

[0093] Based on the examples and comparative examples, the performance of the cermet materials was tested:

[0094] (1) Bending strength: Measured in accordance with GB / T 3851-2015 standard;

[0095] (2) Rockwell hardness: measured according to GB / T 3849.1-2015 standard;

[0096] (3) Fracture toughness: Measured according to GB / T 33819-2017;

[0097] Table 1 shows the final measured performance:

[0098] Table 1

[0099]

[0100] As can be seen from Table 1, under similar hardness conditions, the toughness and high-temperature bending strength of the cermet materials in the examples are significantly better than those in the comparative examples. This is because the examples use GH3625 high-temperature alloy as the binder phase, and achieve uniform mixing of powders across scales through a synergistic process of "dry grinding-ultrasonic dispersion-wet grinding". Combined with segmented vacuum sintering to form a weak core / coreless structure, the interfacial stress is reduced. At the same time, the Ni-Cr matrix of the high-temperature alloy forms a dense Cr2O3 oxide film, which, together with the high-temperature stability of the Ti(C,N) ceramic phase, inhibits the decay of high-temperature performance.

[0101] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for producing a high temperature alloy-Ti(C,N) cermet material, characterized in that, Includes the following steps: S1. High-temperature alloy powder and Ti(C,N) ceramic powder are subjected to dry grinding, ultrasonic dispersion, wet grinding, and drying to obtain cermet powder; the high-temperature alloy powder is GH3625 high-temperature alloy; the mass ratio of the high-temperature alloy powder to Ti(C,N) ceramic powder is 1:(1-4); the process parameters for dry grinding are: the ball milling medium is hard alloy balls, the ball-to-material ratio is (3-6):1, the ball milling speed is 100rpm-200rpm, the ball milling time is 2h-6h, and the air pressure is 0.3atm-0.5atm; during the ultrasonic dispersion process, [the following steps are taken]... The raw materials consist of 1.2-1.8 times their total weight in ethanol and 1-3 wt% of a polyethylene glycol solution. The vacuum sintering process is divided into three stages: the first stage involves heating to 700-1000℃ at a rate of 0.2-0.4℃ / min and holding for 1-3 hours; the second stage involves heating to 1100-1300℃ at a rate of 0.5-1℃ / min and holding for 2-4 hours; and the third stage involves heating to 1400-1500℃ at a rate of 1-2℃ / min and holding for 0.5-2 hours. S2. The metal-ceramic powder described in S1 is subjected to bidirectional pressing, vacuum sintering and cooling to obtain the high-temperature alloy-Ti(C,N) composite metal-ceramic material.

2. The preparation method of the high-temperature alloy-Ti(C,N) composite cermet material according to claim 1, characterized in that, In S1, the particle size of the high-temperature alloy powder is 15μm-25μm; And / or, the particle size of the Ti(C,N) ceramic powder is 0.5μm-2μm.

3. The preparation method of the high-temperature alloy-Ti(C,N) composite cermet material according to claim 1, characterized in that, In S1, the process parameters for wet milling are as follows: the milling medium is cemented carbide balls, the ball-to-material ratio is (4-8):1, the milling speed is 220rpm-350rpm, and the milling time is 12h-24h.

4. The preparation method of the high-temperature alloy-Ti(C,N) composite cermet material according to claim 1, characterized in that, In S1, the drying is carried out using an infrared drying oven at 70℃-85℃.

5. The method for preparing the high-temperature alloy-Ti(C,N) composite cermet material according to claim 1, characterized in that, In S2, the pressure of the bidirectional compression is 180MPa-300MPa.

6. The method for preparing the high-temperature alloy-Ti(C,N) composite cermet material according to claim 1, characterized in that, In S2, the cooling process involves first introducing flowing Ar gas at 0.5 atm to 0.8 atm to cool the temperature to 190°C to 210°C, and then cooling it along with the furnace.

7. The high-temperature alloy-Ti(C,N) composite cermet material prepared by the method according to any one of claims 1-6, characterized in that, The elemental composition and mass percentage of the high-temperature alloy-Ti(C,N) composite cermet material are as follows: Ti 32.53%-51.89%, Ni 12.27%-30.68%, Cr 4.25%-10.63%, Mo 1.90%-4.75%, Fe 0.69%-1.73%, Nb 0.75%-1.87%, Al 0.07%-0.18%, Co 0.01%-0.02%, Cu 0.01%-0.03%, C 8.14%-13.00%, and N 9.48%-15.16%.

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