A high-performance aluminum nitride ceramic rapid sintering method

Abstract

The application discloses a high-performance aluminum nitride ceramic rapid sintering method and belongs to the technical field of ceramic materials, and comprises the following steps: preparing ceramic raw materials according to a formula: uniformly mixing high-purity aluminum nitride powder, a sintering aid, a hydrolysis-resistant agent and a solvent, and drying under a nitrogen atmosphere; the ratio of the high-purity aluminum nitride powder, the sintering aid and the hydrolysis-resistant agent is 1:1%-3%:0.5%-1.5%; primary sintering of the ceramic: heat-press sintering the uniformly mixed aluminum nitride powder under a neutral or reducing atmosphere at 1650-1850 DEG C and a pressure of 20-30 MPa for 10-60 min, so that the density of the aluminum nitride powder reaches more than 99%; secondary sintering of the ceramic: sintering the primary-sintered aluminum nitride ceramic under a reducing atmosphere at 1850-2000 DEG C under normal pressure for 1-6 h. The prepared aluminum nitride ceramic not only has high heat conduction performance, but also has high sintering efficiency; meanwhile, the problem of waste gas generated in the degreasing process is avoided, and the environment is protected.

Description

Technical Field

[0001] This invention belongs to the field of ceramic materials technology, specifically relating to a rapid sintering method for high-performance aluminum nitride ceramics. Background Technology

[0002] Aluminum nitride ceramic materials are hailed as the ideal substrate material for next-generation high-power microelectronic devices due to their excellent material properties (high thermal conductivity, low dielectric constant, non-toxicity, superior insulation performance, high temperature and corrosion resistance, thermal expansion coefficient matching that of silicon, and good mechanical properties).

[0003] Conventional aluminum nitride ceramic sintering generally employs either atmospheric pressure sintering or hot pressing sintering. Atmospheric pressure sintering has more stringent process requirements, necessitating the addition of large amounts of binders, plasticizers, and sintering aids during green body formation. Typically, atmospheric pressure sintering requires 5%-10% of the aluminum nitride powder weight in sintering aids, resulting in a higher formation of the second phase. Higher sintering temperatures and longer holding times are needed to produce aluminum nitride ceramics with good thermal conductivity. Furthermore, a debinding process is generally required after green body formation and before sintering, with slow heating below 500℃ (heating rate <1℃ / min) to prevent cracking of the green body during debinding. During high-temperature sintering, a lower heating rate (heating rate <3℃ / min) is also required to ensure that the aluminum nitride ceramic does not develop significant defects during densification, leading to high energy consumption and low production efficiency. Furthermore, adding large amounts of binders and plasticizers not only results in significant carbon residue after degreasing, affecting the final properties of aluminum nitride ceramics, but also generates waste gas during the degreasing process, causing environmental pollution. Hot pressing sintering eliminates the need for large amounts of binders, plasticizers, and sintering aids; it requires only a small amount of sintering aids and allows for rapid sintering at extremely high heating rates, enabling rapid densification of aluminum nitride ceramics with good mechanical properties. However, hot pressing sintering suffers from the disadvantage that impurities such as the second phase in aluminum nitride ceramics are not easily volatilized, making it difficult to prepare aluminum nitride ceramics with high thermal conductivity.

[0004] Therefore, both sintering methods have their drawbacks. In the existing technology, in order to obtain aluminum nitride ceramic materials, the sintering method used is usually modified accordingly to overcome its drawbacks. Summary of the Invention

[0005] The purpose of this invention is to provide a rapid sintering method for high-performance aluminum nitride ceramics, solving the problems of low performance or low production efficiency of aluminum nitride ceramics produced by existing preparation processes.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A rapid sintering method for high-performance aluminum nitride ceramics includes the following steps:

[0008] Step S1: Prepare ceramic raw materials according to the formula: Mix high-purity aluminum nitride powder, sintering aid, anti-hydrolysis agent and solvent evenly, and dry under nitrogen atmosphere. The ratio of high-purity aluminum nitride powder, sintering aid and anti-hydrolysis agent is 1:1%-3%:0.5%-1.5%.

[0009] Step S2, initial firing of ceramics: The uniformly mixed aluminum nitride powder is hot-pressed and sintered at 1650-1850℃ and 20-30MPa for 10-60 minutes under a neutral or reducing atmosphere to achieve a density of over 99%.

[0010] Step S3, ceramic re-firing: The initially fired aluminum nitride ceramic is sintered at 1850-2000℃ and atmospheric pressure for 1-6 hours under a reducing atmosphere.

[0011] A further improvement to the technical solution of this invention lies in that the high-purity aluminum nitride powder has an O content of <0.7%, a purity of >99%, a particle size of <2μm, and a specific surface area of ​​>2.3m². 2 / g.

[0012] A further improvement of the technical solution of the present invention is that the sintering aid includes at least one of yttrium oxide, yttrium fluoride, dysprosium oxide, calcium oxide, and calcium fluoride, with a purity > 99.9% and a particle size < 500 nm.

[0013] A further improvement of the technical solution of the present invention is that the anti-hydrolysis agent includes at least one of oleic acid, stearic acid, Tween-80, phosphoric acid, aluminum dihydrogen phosphate, and magnesium dihydrogen phosphate.

[0014] A further improvement of the technical solution of the present invention is that the specific steps of the initial firing of the ceramic are as follows: the uniformly mixed powder is filled into a graphite high-temperature hot press furnace for sintering, and the sintering temperature is 1650-1850℃ in a nitrogen atmosphere or a reducing atmosphere for 10-60 minutes, so that the density reaches more than 99%.

[0015] A further improvement to the technical solution of the present invention is that the specific sintering process is as follows: the temperature is raised to 1500℃ at a rate of 25℃ / min, pressure is applied, the temperature is raised to 1650-1850℃ at a rate of 20℃ / min, the pressure is 20-30 MPa, the temperature and pressure are maintained for 10-60 minutes, and then the temperature and pressure are naturally reduced. During the sintering process, flowing nitrogen gas is introduced.

[0016] A further improvement of the technical solution of the present invention is that the specific steps of the ceramic re-firing are as follows: the aluminum nitride ceramic after initial firing is placed in a graphite high-temperature furnace for sintering at a temperature of 1850-2000℃ in a nitrogen atmosphere or a reducing atmosphere for 1-6 hours.

[0017] A further improvement to the technical solution of the present invention is that the specific process of ceramic re-firing and sintering is as follows: the temperature is raised to 1500℃ at a rate of 25℃ / min, then raised to 1850-2000℃ at a rate of 20℃ / min, held for 1-6 hours and then cooled naturally, with flowing nitrogen gas passing through during the sintering process.

[0018] A high-performance aluminum nitride ceramic is prepared using the aforementioned rapid sintering method for high-performance aluminum nitride ceramics. The high-performance aluminum nitride ceramic has a single AlN phase in its crystal phase and no other grain boundary phases.

[0019] A further improvement of the technical solution of the present invention lies in: the thermal conductivity of the high-performance aluminum nitride ceramic.

[0020] ≥240W / mk, flexural strength ≥350MPa, 3.25<bulk density<3.28g / cm³ 3 .

[0021] The technological advancements achieved by this invention due to the adoption of the above technical solutions are as follows:

[0022] This invention overcomes the shortcomings of conventional hot-pressing and atmospheric-pressure sintering by ingeniously improving the sintering method. The initial firing uses hot-pressing to rapidly densify the aluminum nitride ceramic, allowing for rapid temperature rise and significantly improving sintering efficiency. Furthermore, only a small amount of sintering aid is needed throughout the entire aluminum nitride ceramic sintering process; no binder or plasticizer is required, which helps reduce impurities in the finished product, improves the sintering performance of the aluminum nitride ceramic, and eliminates the need for a debinding process. This not only improves sintering efficiency but also eliminates waste gas emissions during debinding, making it environmentally friendly. The secondary firing uses atmospheric-pressure sintering heat treatment, which completely removes impurities such as the second phase generated by the reaction of sintering aids and alumina during the initial firing of the aluminum nitride ceramic. The prepared aluminum nitride ceramic achieves a single AlN phase with no internal defects, thus enabling the preparation of high-performance aluminum nitride ceramics.

[0023] This invention employs hot-pressing sintering in the initial firing stage, eliminating the need for dry pressing and cold isostatic pressing to prepare the green body, thus saving operational steps. The rapid temperature rise during sintering allows for quick densification of the ceramic, significantly improving sintering efficiency. Furthermore, the absence of large amounts of sintering aids reduces the formation of second phases during sintering, providing a foundation for complete removal of the second phase during atmospheric pressure re-firing. In addition, the absence of binders, plasticizers, and other green body forming materials eliminates the need for debinding, saving debinding time and avoiding the waste gas generation problem during debinding, which is environmentally friendly. Atmospheric pressure re-firing heat treatment helps to expel lattice oxygen and volatilize residual second phases at grain boundaries, resulting in aluminum nitride ceramics with not only high thermal conductivity but also rapid sintering efficiency, enabling high-efficiency production. Attached Figure Description

[0024] Figure 1A scanning electron microscope image of the cross-section of the aluminum nitride ceramic prepared in Example 1;

[0025] Figure 2 XRD pattern of aluminum nitride ceramic prepared in Example 1;

[0026] Figure 3 Scanning electron microscope image of the cross-section of the aluminum nitride ceramic prepared in Comparative Example 1;

[0027] Figure 4 Scanning electron microscope image of the cross-section of the aluminum nitride ceramic prepared for Comparative Example 2. Detailed Implementation

[0028] To facilitate understanding of the present invention, a more comprehensive description will be given below with reference to specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of the present invention.

[0029] The aluminum nitride powder and sintering aids used in the following examples are all high-purity ultrafine powders, wherein the aluminum nitride powder has a particle size of <2μm, a purity of ≥99%, and an oxygen content of <0.7%; and the sintering aid has a particle size of <500nm and a purity of >99.9%.

[0030] Example 1

[0031] (1) Mixing raw materials

[0032] Aluminum nitride powder, yttrium oxide powder, calcium fluoride powder, oleic acid, solvent, and milling media were placed in a rolling ball mill jar and milled for 6 hours. The milled slurry was then dried at 80°C under a nitrogen atmosphere.

[0033] Based on 100% by mass of aluminum nitride powder, the amounts of yttrium oxide powder, calcium fluoride powder, oleic acid, solvent, and milling media added are 2%, 0.5%, 0.3%, 100%, and 500%, respectively. The solvent is anhydrous ethanol, and the milling media is alumina balls.

[0034] (2) Initial firing after hot pressing

[0035] The dried mixed powder was placed in a graphite hot press furnace for hot pressing and sintering to obtain the initial sintered product with a density of 3.29 g / cm³. 3 .

[0036] The specific sintering process is as follows: the temperature is increased to 1500℃ at a rate of 25℃ / min, at which point pressure is applied; the temperature is then increased to 1800℃ at a rate of 20℃ / min, at which point the pressure is 20 MPa; the temperature and pressure are maintained for 60 minutes, followed by natural cooling and depressurization. Flowing nitrogen gas is purged during the sintering process. The total initial sintering time is 135 minutes.

[0037] (3) Reheating under normal pressure

[0038] The product after initial firing is placed in a graphite sintering furnace for atmospheric pressure refiring to obtain high-performance aluminum nitride ceramic products.

[0039] The specific sintering process was as follows: the temperature was increased to 1500℃ at a rate of 25℃ / min, then increased to 1900℃ at a rate of 20℃ / min, held at that temperature for 180 min, and then allowed to cool naturally. Flowing nitrogen gas was introduced during the sintering process. The total time for the second sintering was 260 min, and the total time for this sintering was 395 min.

[0040] The aluminum nitride ceramic in this embodiment was characterized by scanning electron microscopy and XRD. The results are shown in the figure. Figure 1 , Figure 2 ,from Figure 1 , Figure 2 It can be seen that the high-strength, high-thermal-conductivity aluminum nitride ceramic prepared in this embodiment contains only the aluminum nitride phase.

[0041] The aluminum nitride ceramic prepared in this embodiment was tested, and its properties are as follows: bulk density is 3.27 g / cm³. 3 It has a thermal conductivity of 245 W / m·K and a flexural strength of 380 MPa.

[0042] Example 2

[0043] (1) Mixing raw materials

[0044] Aluminum nitride powder, yttrium oxide powder, calcium oxide powder, stearic acid, Tween 80, solvent, and milling media were placed in a rolling ball mill jar and milled for 6 hours. The milled slurry was then dried at 110°C under a nitrogen atmosphere.

[0045] Based on 100% by mass of aluminum nitride powder, the amounts of yttrium oxide powder, calcium oxide powder, stearic acid, Tween 80, solvent, and milling media added are 2%, 1%, 1%, 0.5%, 110%, and 500%, respectively. The solvent is anhydrous ethanol, and the milling media is alumina balls.

[0046] (2) Initial firing after hot pressing

[0047] The dried mixed powder was placed in a graphite hot press furnace for hot pressing and sintering to obtain the initial sintered product with a density of 3.28 g / cm³. 3 .

[0048] The specific sintering process is as follows: the temperature is increased to 1500℃ at a rate of 25℃ / min, at which point pressure is applied; the temperature is then increased to 1750℃ at a rate of 20℃ / min, at which point the pressure is 25 MPa; the temperature and pressure are maintained for 30 minutes, followed by natural cooling and depressurization. Flowing nitrogen gas is introduced during the sintering process. The total initial sintering time is 102.5 minutes.

[0049] (3) Reheating under normal pressure

[0050] The product after initial firing is placed in a graphite sintering furnace for atmospheric pressure refiring to obtain high-performance aluminum nitride ceramic products.

[0051] The specific sintering process was as follows: the temperature was increased to 1500℃ at a rate of 25℃ / min, then increased to 1950℃ at a rate of 20℃ / min, held at that temperature for 120 min, and then allowed to cool naturally. Flowing nitrogen gas was introduced during the sintering process. The total time for the second sintering was 202.5 min, and the total time for this sintering was 305 min. The high-strength, high-thermal-conductivity aluminum nitride ceramic substrate prepared in this embodiment contains only the aluminum nitride phase.

[0052] The aluminum nitride ceramic prepared in this embodiment was tested, and its properties are as follows: bulk density is 3.26 g / cm³. 3 It has a thermal conductivity of 250 W / m·K and a flexural strength of 363 MPa.

[0053] Example 3

[0054] (1) Mixing raw materials

[0055] Aluminum nitride powder, yttrium oxide powder, yttrium fluoride powder, phosphoric acid, solvent, and milling media were placed in a rolling ball mill jar and milled for 6 hours. The milled slurry was then dried at 90°C under a nitrogen atmosphere.

[0056] Based on 100% by mass of aluminum nitride powder, the amounts of yttrium oxide powder, yttrium fluoride powder, phosphoric acid, solvent, and milling media added are 2%, 1%, 1%, 120%, and 500%, respectively. The solvent is anhydrous ethanol, and the milling media is alumina balls.

[0057] (2) Initial firing after hot pressing

[0058] The dried mixed powder was placed in a graphite hot press furnace for hot pressing and sintering to obtain the initial sintered product with a density of 3.30 g / cm³. 3 .

[0059] The specific sintering process is as follows: the temperature is increased to 1500℃ at a rate of 25℃ / min, at which point pressure is applied; the temperature is then increased to 1800℃ at a rate of 20℃ / min, at which point the pressure is 25 MPa; the temperature and pressure are maintained for 60 minutes, followed by natural cooling and depressurization. Flowing nitrogen gas is purged during the sintering process. The total initial sintering time is 135 minutes.

[0060] (3) Reheating under normal pressure

[0061] The product after initial firing is placed in a graphite sintering furnace for atmospheric pressure refiring to obtain high-performance aluminum nitride ceramic products.

[0062] The specific sintering process was as follows: the temperature was increased to 1500℃ at a rate of 25℃ / min, then increased to 2000℃ at a rate of 20℃ / min, held at that temperature for 60 minutes, and then allowed to cool naturally. Flowing nitrogen gas was introduced during the sintering process. The total time for the second sintering was 145 minutes, and the total time for this sintering was 280 minutes.

[0063] The aluminum nitride ceramic prepared in this embodiment was tested, and its properties are as follows: bulk density is 3.27 g / cm³. 3 It has a thermal conductivity of 261 W / m·K and a flexural strength of 351 MPa.

[0064] Comparative Example 1

[0065] (1) Mixing raw materials

[0066] Aluminum nitride powder, yttrium oxide powder, oleic acid, PVB, DBP, solvent, and milling media were placed in a rolling ball mill jar and milled for 10 hours to obtain a cast slurry.

[0067] Based on 100% of the aluminum nitride powder mass, the amounts of yttrium oxide powder, oleic acid, PVB, DBP, solvent, and milling media added are 8%, 0.3%, 10%, 5%, 100%, and 500%, respectively. The solvent is a 1:1 mixture of ethanol and n-butanol, and the milling media are alumina balls.

[0068] (2) Green body preparation

[0069] The slurry is cast and molded to a thickness of 0.5 mm, and then isostatically pressed at a pressure of 10-15 MPa and a temperature of 70°C.

[0070] (3) Degreasing

[0071] Degreasing is performed under a nitrogen atmosphere at a temperature of 500℃.

[0072] The specific degreasing process is as follows: heat to 500℃ at a rate of 1℃ / min and hold at that temperature for 60 minutes. The total degreasing time is 560 minutes.

[0073] (4) Sintering

[0074] The degreased green body is placed in a graphite high-temperature furnace for atmospheric pressure sintering to obtain aluminum nitride ceramic products.

[0075] The specific sintering process was as follows: the temperature was increased to 1200℃ at a rate of 10℃ / min, then to 1500℃ at a rate of 5℃ / min, and finally to 1900℃ at a rate of 2℃ / min. The temperature was held for 360 minutes, followed by natural cooling. Flowing nitrogen gas was introduced during the sintering process. The total sintering time was 740 minutes, and the total time for debinding and sintering in this case was 1300 minutes.

[0076] The aluminum nitride ceramics in this comparative example were characterized by scanning electron microscopy, and the results are shown in the figure. Figure 3 ,from Figure 3 It can be seen that the aluminum nitride ceramic prepared in this comparative example contains a second phase at the grain boundaries in addition to the aluminum nitride phase.

[0077] The aluminum nitride ceramic prepared in this comparative example was tested, and its properties are as follows: bulk density is 3.31 g / cm³. 3 It has a thermal conductivity of 238 W / m·K and a flexural strength of 330 MPa.

[0078] Comparative Example 2

[0079] (1) Mixing raw materials

[0080] Aluminum nitride powder, yttrium oxide powder, oleic acid, solvent, and milling media were placed in a rolling ball mill jar and milled for 6 hours. The milled slurry was then dried at 100°C under a nitrogen atmosphere.

[0081] Based on 100% aluminum nitride powder, the amounts of yttrium oxide powder, oleic acid, solvent, and milling media added are 3%, 0.5%, 120%, and 500%, respectively. The solvent is anhydrous ethanol, and the milling media is alumina balls.

[0082] (2) Hot pressing sintering

[0083] The dried mixed powder is placed in a graphite hot press furnace for hot pressing and sintering to obtain aluminum nitride ceramic products.

[0084] The specific sintering process is as follows: the temperature is increased to 1500℃ at a rate of 25℃ / min, at which point pressure is applied; the temperature is then increased to 1800℃ at a rate of 20℃ / min, at which point the pressure is 25 MPa; the temperature and pressure are maintained for 60 minutes, followed by natural cooling and depressurization. Flowing nitrogen gas is introduced during the sintering process. The total hot-pressing sintering time is 135 minutes.

[0085] The aluminum nitride ceramics in this comparative example were characterized by scanning electron microscopy, and the results are shown in the figure. Figure 4 ,from Figure 4 It can be seen that the aluminum nitride ceramic prepared in this comparative example contains a second phase at the grain boundaries in addition to the aluminum nitride phase.

[0086] The aluminum nitride ceramic prepared in this comparative example was tested, and its properties are as follows: bulk density is 3.32 g / cm³. 3 It has a thermal conductivity of 165 W / m·K and a flexural strength of 403 MPa.

[0087] The results of thermal conductivity, flexural strength, and total sintering time of the aluminum nitride ceramics in Examples 1-3 and Comparative Examples 1-2 are compared and summarized in Table 1:

[0088] Table 1. Results of thermal conductivity, flexural strength, and total sintering time for aluminum nitride ceramics.

[0089] thermal conductivity Flexural strength Total sintering time Example 1 245W / mK 380Mpa 395min Example 2 250W / mK 363Mpa 305min Example 3 261W / mK 351 MPa 280min Comparative Example 1 238W / mK 330Mpa 1300min Comparative Example 2 165W / mK 403Mpa 135min

[0090] Note: In the above tests, the flexural strength was tested using a Shimadzu flexural strength tester, and the thermal conductivity was tested using a Hot Disk TPS2500S thermal conductivity tester.

[0091] As shown in Table 1, compared with Comparative Example 1 (conventional atmospheric pressure sintering), the sintering time of the present invention can be shortened by more than 4 times, and the thermal conductivity is also higher than that of the atmospheric pressure sintering sample. Compared with Comparative Example 2 (conventional hot pressing sintering), the sintering time of the present invention is longer than that of conventional hot pressing sintering, but the thermal conductivity is much higher than that of the conventional hot pressing sintering sample.

[0092] The above description is merely an embodiment of the invention's technical content. Any modifications or variations made by those skilled in the art using this invention are within the scope of the invention's claims, and are not limited to those disclosed in the embodiments.

Claims

1. A rapid sintering method for high-performance aluminum nitride ceramics, characterized in that... Includes the following steps: Step S1: Prepare ceramic raw materials according to the formula: Mix high-purity aluminum nitride powder, sintering aid, anti-hydrolysis agent and solvent evenly, and dry under nitrogen atmosphere. The ratio of high-purity aluminum nitride powder, sintering aid and anti-hydrolysis agent is 1:1%-3%:0.5%-1.5%; Step S2, initial firing of ceramics: The uniformly mixed aluminum nitride powder is hot-pressed and sintered at 1650-1850℃ and 20-30MPa for 10-60 minutes under a nitrogen atmosphere or a reducing atmosphere to achieve a density of over 99%. Step S3, ceramic re-firing: The aluminum nitride ceramic after initial firing is sintered at 1850-2000℃ and atmospheric pressure for 1-6 hours under nitrogen or reducing atmosphere. The specific steps of the initial firing of the ceramic are as follows: the uniformly mixed powder is filled into a graphite high-temperature hot press furnace for sintering, and the sintering temperature is 1650-1850℃ in a nitrogen atmosphere or reducing atmosphere for 10-60 minutes, so that its density reaches more than 99%. The specific steps of the ceramic re-firing are as follows: the aluminum nitride ceramic after initial firing is placed in a graphite high-temperature furnace for sintering at a temperature of 1850-2000℃ in a nitrogen atmosphere or reducing atmosphere for 1-6 hours.

2. The rapid sintering method for high-performance aluminum nitride ceramics according to claim 1, characterized in that: The high-purity aluminum nitride powder has an oxygen content of <0.7%, a purity of >99%, a particle size of <2μm, and a specific surface area of ​​>2.3m². 2 / g.

3. The rapid sintering method for high-performance aluminum nitride ceramics according to claim 1, characterized in that: The sintering aids include at least one of yttrium oxide, yttrium fluoride, dysprosium oxide, calcium oxide, and calcium fluoride, with a purity > 99.9% and a particle size < 500 nm.

4. The rapid sintering method for high-performance aluminum nitride ceramics according to claim 1, characterized in that: The anti-hydrolysis agent includes at least one of oleic acid, stearic acid, Tween-80, phosphoric acid, aluminum dihydrogen phosphate, and magnesium dihydrogen phosphate.

5. The rapid sintering method for high-performance aluminum nitride ceramics according to claim 1, characterized in that: The specific process of initial firing is as follows: the temperature is increased to 1500℃ at a rate of 25℃ / min, pressure is applied, the temperature is increased to 1650-1850℃ at a rate of 20℃ / min, the pressure is 20-30MPa at this time, the temperature and pressure are maintained for 10-60min, and then the temperature and pressure are naturally reduced. During the sintering process, flowing nitrogen is introduced.

6. The rapid sintering method for high-performance aluminum nitride ceramics according to claim 1, characterized in that: The specific process of ceramic re-firing and sintering is as follows: the temperature is raised to 1500℃ at a rate of 25℃ / min, then raised to 1850-2000℃ at a rate of 20℃ / min, held for 1-6 hours and then cooled naturally. Flowing nitrogen gas is introduced during the sintering process.

7. A high-performance aluminum nitride ceramic, characterized in that: The high-performance aluminum nitride ceramic is prepared using a rapid sintering method according to any one of claims 1-6, wherein the high-performance aluminum nitride ceramic has a single AlN phase and no other grain boundary phases.

8. The high-performance aluminum nitride ceramic according to claim 7, characterized in that: The high-performance aluminum nitride ceramic has a thermal conductivity ≥240W / mK, a flexural strength ≥350MPa, and a g / cm³ strength of 3.25g / cm³. 3 <bulk density <3.28 g / cm³ 3 .

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