CN115010510A

CN115010510A - Low-thermal-conductivity zirconium carbide-coated zirconia ceramic foam material and preparation method thereof

Info

Publication number: CN115010510A
Application number: CN202210444430.7A
Authority: CN
Inventors: 姚倩钰; 范晓慧; 倪娜; 赵晓峰
Original assignee: Shanghai Jiaotong University
Current assignee: Shanghai Jiaotong University
Priority date: 2022-04-25
Filing date: 2022-04-25
Publication date: 2022-09-06
Anticipated expiration: 2042-04-25
Also published as: CN115010510B

Abstract

The invention relates to a zirconium carbide coated zirconia ceramic foam material with low thermal conductivity and a preparation method thereof, wherein the preparation method comprises the following steps: and (3) carrying out vacuum impregnation on the yttria-stabilized zirconia porous ceramic blank with micron-level pores by using phenolic resin to obtain a ceramic foam precursor. And then, obtaining the zirconium carbide coated zirconia ceramic foam material after heating, curing, high-temperature roasting and in-situ carbothermic reduction reaction sintering. Compared with the prior art, the invention provides the method for preparing the zirconium carbide coated zirconia ceramic foam, and the method obviously reduces the sintering densification temperature of zirconium carbide. The composite foam material has excellent mechanical properties and low thermal conductivity. Meanwhile, the method can effectively regulate and control the pore structure and the mechanical property of the ceramic, realizes the preparation of the zirconium carbide and zirconium oxide composite ceramic foam with low thermal conductivity under the condition of lower temperature, and has wide application prospect.

Description

Low-thermal-conductivity zirconium carbide-coated zirconia ceramic foam material and preparation method thereof

Technical Field

The invention belongs to the technical field of heat insulation materials, and relates to a zirconium carbide-coated zirconia ceramic foam material with low thermal conductivity and a preparation method thereof, in particular to a zirconium carbide-coated zirconia ceramic foam material with good hole structure reproducibility, compact hole wall and low thermal conductivity and an in-situ carbothermic reduction reaction preparation method.

Background

The porous ultrahigh Temperature Ceramics (UHTCs) has the advantages of both the porous Ceramics and the UHTCs, such as low volume weight, High specific surface area, good chemistry and High Temperature stability. These unique properties make porous UHTCs have broad application prospects in high-temperature insulation, filtration of high-temperature molten metal and corrosive gas, catalyst support, high-temperature solar absorption and the like. For high temperature insulation applications, the thermal conductivity should be less than 1.5 W.m ^-1 ·K ^-1 The compressive strength should be greater than 1 MPa.

Zirconium carbide (ZrC) has attracted considerable attention in various fields of application because of its excellent physical and chemical properties. ZrC has a high melting point, desirably high specific strength, which makes ZrC an attractive candidate for aerospace ultra-high temperature applications (involving temperatures in excess of 1600 ℃). The demand for lightweight insulation materials is based on current aerospace development trends. Porous ceramic materials, such as ZrC foam, combine weight, structural stability and low thermal conductivity, making them potentially useful for many applications in very high speed aircraft, including tip and leading edge applications. The durability and weight advantages of this material can provide a significant savings in rocket payload-per-pound-to-track costs.

Currently, research on ZrC mainly focuses on the synthesis, sintering, densification of powder, and the thermal conductivity and mechanical properties of bulk materials. The preparation method of zirconium carbide ceramic foam includes a template method, a direct foaming method, a sol-gel method, a chemical vapor deposition method and the like, wherein the template method usually uses foam of carbon-containing materials as a template to obtain zirconium carbide foam through reaction infiltration. Li Fei et al [ Li, Fei, Weichao Bao, De-Wei Ni, Xiao Huang, and Guo-Jun Zhang. A thermo set hybrid sol for the synthesis of zirconium carbide foam via a reactive method. journal of materials.26,409-17(2018) ] use melamine foam as a template sol to impregnate ZrC/SiC composite foam, the sintering temperature is 1500 ℃, the porosity of the material is about 80%, the compressive strength is 0.4MPa, the pillars and the inner walls of the ZrC foam obtained by the method are not dense, resulting in poor mechanical properties. The ZrC foam obtained by Li Fei et al [ Li, F., Kang, Z., Huang, X., Wang, X.G. & Zhang, G.J.preparation of zirconium carbide foam by direct foaming method.J.Eur.Ceram.Soc.34, 3513-3520 (2014) ] by a direct foaming method has the sintering temperature of 1600 ℃, the porosity of the material is 85%, the compressive strength of the material is about 0.4MPa, and the thermal conductivity at 50 ℃ is 0.96W/(m K), and the ZrC foam obtained by the method has relatively poor mechanical properties. Jiang, J et al [ Jiang, J., Wang, S., Li, W. & Chen, Z.Fabrication and characterization of ZrC foam by melt infiltration.J.alloys composite.695, 2295-2300 (2017) ] adopt a reaction infiltration method, the sintering temperature is 1600 ℃, the porosity of the material is 75.38%, the compressive strength is about 26.5 +/-6.28 MPa, and the thermal conductivity at 27 ℃ is 40.411W/(m K). Li Fei et al [ Li, Fei, Xin-Gang Wang, Xiao Huang, Ji-Xuan Liu, Weichao Bao, Guo-Jun Zhang, and hongzhihi Wang.preparation of ZrC/SiC pore self-supporting monolithis via gel process using polyethylene glycol as phase separation inducer, J.Eur.Ceram.Soc.38.4806-2018 ] used a sol-gel process to obtain ZrC/SiC foams with polyethylene glycol (PEG) as phase separation inducer, sintering temperatures of 1300-1500 ℃, porosity of the material is about 70%, compressive strength is 0.69MPa, which is based on gelation of inorganic zirconium oxychloride and gelation and tunable pore formation of a combined polymerization reaction of organic furfuryl alcohol and polyethylene glycol, resulting in crack-free mixed monoliths, but still with relatively high porosity. In addition, patent cn201410477411.x discloses a method for preparing ZrC ceramic foam, which adopts a two-step infiltration method of low-temperature infiltration-high-temperature reaction, has excellent mechanical properties, and the obtained material is formed by mutually connecting pentagonal dodecahedron or open-cell spheres serving as basic units. However, the volume fraction of the ZrC phase contained in the material is lower than 10%, the grain size is larger (micron-sized), the technological condition requirements are strict, the sintering temperature is high, the operation difficulty is high, and the safety is low. The patent CN202010065700.4 adopts a direct foaming method to prepare the ZrC-rich phase foamed ceramic, has high ZrC phase mass percentage and simple process. However, the pore structure in this material is naturally foamed, and the bubbles are fixed by natural drying, so that the solid-liquid distribution is likely to be uneven, resulting in uneven distribution of the ceramic phase.

In view of the above, in recent years, researchers have tried to realize ZrC intermediate temperature sintering preparation through new preparation processes, such as sol-gel, reaction infiltration, and the like, but foam materials themselves are difficult to be sintered sufficiently, so that the skeleton of the foam material cannot be densified, and the mechanical strength of the foam is low. Because of the strong covalent bond and the low self-diffusion coefficient in ZrC, the traditional powder metallurgy preparation method needs to adopt high temperature (the temperature is more than 2000 ℃) to sinter so as to obtain enough mechanical strength. Therefore, the currently available preparation method of the ZrC structural foam has the disadvantages of high process operation difficulty and high cost, or the obtained foam material has high thermal conductivity and low mechanical strength.

Disclosure of Invention

The invention aims to provide a zirconium carbide coated zirconia ceramic foam material with low thermal conductivity and a preparation method thereof, which are used for solving at least one of the following technical problems: the high-temperature synthesis and sintering of the porous zirconium carbide ceramic have high requirements on equipment, complex process, difficult control, non-compact sintering and high sintering temperature.

The purpose of the invention can be realized by the following technical scheme:

a preparation method of zirconium carbide coated zirconia ceramic foam material comprises the following steps:

s1: preparing a yttria-Stabilized Zirconia porous ceramic body (YSZ) with micron-level pores;

s2: adopting phenolic resin to vacuum-impregnate a yttria-stabilized zirconia porous ceramic blank with micron-level pores, and heating the zirconia porous ceramic blank for curing, and roasting at high temperature in an inert atmosphere or a reducing atmosphere to obtain a zirconia/carbon (YSZ/C) ceramic foam precursor;

s3: carrying out in-situ carbothermic reduction reaction on the YSZ/C ceramic foam precursor and pressureless sintering to obtain zirconium carbide (ZrC) coated zirconium oxide (ZrO) ₂ ) A ceramic foam material.

Further, in step S1, with reference to steps 1) -3) in CN202110438410.4, a yttria-stabilized zirconia porous ceramic body with a pore at a micron level was prepared.

Further, Y used ₂ O ₃ +ZrO ₂ In the nano-powder, Y ₂ O ₃ The molar content of (a) is 1 to 5 mol%.

Further, in step S2, the phenolic resin is mixed with the yttria-stabilized zirconia porous ceramic body with micron-level pores in the form of a phenolic resin solution with a mass fraction of 70-90%.

Further, in step S2, the mass ratio of the yttria-stabilized zirconia ceramic body with micron-level pores to the phenolic resin solution is not more than 1.7. The upper limit of the mass ratio is determined by the carbothermic reduction reaction formula ZrO ₂ The +3C ═ ZrC +2CO is obtained, and when the phenolic resin is too low, the carbothermic reduction reaction is incomplete, and the amount of zirconium carbide produced decreases.

Further, in step S2, the vacuum degree is 5-8Pa, the dipping time is 6-10min, and the dipping temperature is room temperature.

Further, in step S2, in the heating and curing, the heating temperature is 90 to 130 ℃, the heating time is 0.5 to 1.5 hours, and a good curing effect can be maintained under the heating and curing condition, which is beneficial to the preparation and molding of the YSZ/C ceramic foam precursor.

Further, in step S2, in the high-temperature roasting heat treatment, the heat treatment temperature is 900-1200 ℃, and the heat treatment time is 1-4 h; the inert gas is high-purity argon, nitrogen and some reductive gas such as 2-10% H ₂ The gas flow speed of the/Ar mixed gas is 0.2L/min. And before and after high-temperature heat treatment, the temperature rising rate and the temperature reduction rate are preferably controlled to be 2-8 ℃/min.

Further, in step S3, in the pressureless sintering, the sintering temperature is 1600-1900 ℃, and the sintering time is 1-3 h. And preferably, the heating rate and the cooling rate are controlled to be 5-10 ℃/min before and after pressureless sintering.

The zirconium carbide-coated zirconia ceramic foam material is prepared by the method.

The invention provides a method for preparing porous zirconium carbide foam by carbothermic reduction reaction by using porous zirconium oxide as a template and phenolic resin as a carbon source. The method can flexibly regulate and control the structure and microstructure of the pores to optimize and improve the microstructure and performance of the porous zirconium carbide. The method comprises the following specific steps:

firstly, preparing porous yttria-stabilized zirconia ceramic by adopting an ice template method (directional solidification and freeze drying method, please refer to patent CN202110438410.4), taking the porous yttria-stabilized zirconia ceramic as a template, taking phenolic resin as a carbon source, uniformly mixing the porous yttria-stabilized zirconia ceramic and the phenolic resin by using a vacuum stirring defoaming machine, uniformly permeating the phenolic resin into the porous yttria-stabilized zirconia ceramic template, and roasting at high temperature to crack the phenolic resin into carbon; and then sintering at 1600-1900 ℃ under no pressure, and carrying out carbothermic reduction reaction on carbon and zirconium oxide to directly form zirconium carbide coated zirconium oxide ceramic foam.

The zirconium carbide coated zirconia ceramic foam prepared by sintering is compact, has smaller grain size, adjustable pore structure (porosity of 65-85%), low thermal conductivity (3W/(m.K)), and good mechanical properties (compressive strength of more than 14 MPa), and solves the problems of high sintering temperature, no compactness, complex process, high equipment requirement and the like of the traditional method for preparing the sintered zirconium carbide ceramic. Therefore, the invention provides a method for sintering compact zirconium carbide at a lower temperature (1600-1900 ℃), can effectively regulate and control the pore structure and the performance of the ceramic, realizes the preparation of the porous zirconium carbide ceramic with low thermal conductivity at a lower temperature, and has wide application prospect.

Compared with the prior art, the invention has the following characteristics:

the zirconium carbide-zirconia composite porous ceramic is prepared by adopting a micron-level 3YSZ foam material as a hard template, and a compact ZrC layer formed in situ through carbothermic reduction directly covers the inner surface and the outer surface of zirconia, so that the composite foam material with excellent mechanical properties can be obtained. The zirconium carbide coated zirconia ceramic foam prepared by the method has the characteristic of high porosity, the adjustable range of the porosity is 65-85%, the structure is uniform, and the pore wall is compact. The compressive strength along the hole wall direction can reach 14-16 MPa and above. Compared with a nano zirconium carbide blank prepared by the same directional solidification process, the zirconium carbide ceramic foam (4-5 MPa) with the equivalent porosity is obtained after sintering at the same temperature, and the yttrium oxide stabilized zirconia with the equivalent porosity (2-10 MPa) prepared by the same directional solidification process (see patent CN202110438410.4), the composite ceramic foam material has higher compression strength. Moreover, the zirconium carbide coated zirconia ceramic foam has excellent heat insulation performance, and the thermal conductivity is between 0.5 and 2.7W/(m.K) at room temperature and 900 ℃ parallel to the direction of the hole wall, wherein the high-temperature thermal conductivity is the lowest (-0.567W/(m.K)) as 900 ℃.

Drawings

FIG. 1 is a macroscopic view of a zirconium carbide coated zirconia ceramic foam prepared in example 1;

FIG. 2 is a scanning electron micrograph of a cross-section of a zirconium carbide coated zirconia ceramic foam prepared in example 1 taken at an angle parallel to the direction of ice crystal growth;

FIG. 3 is an enlarged view of FIG. 2 at white box;

FIG. 4 is a spectral plot of the surface scan energy of the elements in the white box of FIG. 2;

FIG. 5 is a scanning electron micrograph of a longitudinal cross section (normal to the cross section perpendicular to the direction of ice crystal growth) of a zirconium carbide coated zirconia ceramic foam prepared in example 1;

FIG. 6 is a graph comparing the compressive stress-strain curves of a zirconium carbide coated zirconia ceramic foam prepared in example 2 with a pure zirconium carbide foam;

FIG. 7 is a graph showing the change in thermal conductivity perpendicular to the normal direction of the sheets for a zirconium carbide coated zirconia ceramic foam prepared in example 2 at 100-900 ℃;

FIG. 8 is a graph of compressive stress-strain curves for a zirconium carbide coated zirconia ceramic foam prepared in example 3;

FIG. 9 is a graph of compressive stress-strain curves for a zirconium carbide coated zirconia ceramic foam prepared in example 4.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments.

A zirconium carbide coated zirconia ceramic foam material is prepared by the following steps:

s1: yttria stabilized zirconia with micron level porosity was prepared according to CN 202110438410.4; preferably 1-5 mol% Yttria stabilized zirconia, more preferably 3 mol% Yttria stabilized zirconia (3 mol% Yttria stabilized zirconia, 3YSZ) in micron level pores;

s2: mixing a phenolic resin solution with yttria-stabilized zirconia with micron-level pores by a vacuum impregnation method (the vacuum degree is 5-8Pa, the impregnation time is 6-10min, and the impregnation temperature is room temperature) by adopting a vacuum stirring defoaming machine, heating and curing for 0.5-1.5h at the temperature of 90-130 ℃, and then roasting and heat treating for 1-4h at the temperature of 900-1200 ℃ under an inert atmosphere to obtain a YSZ/C ceramic foam precursor; wherein the mass concentration of the phenolic resin solution is 70-90%, the mass ratio of the dosage of YSZ and the phenolic resin is not higher than 1.7, and the used inert gases are high-purity argon, nitrogen and some reductive gases such as 2-10% H ₂ The flow rate of the gas/Ar mixed gas is 0.2L/min; and preferably, the heating rate and the cooling rate are controlled to be 2-8 ℃/min before and after the high-temperature heat treatment (in the following examples, the heating rate and the cooling rate are both 5 ℃/min).

S3: pressureless sintering the YSZ/C mixture at the temperature of 1600 ℃ and 1900 ℃ for 1-3h to obtain the zirconium carbide coated zirconia ceramic foam material. And the optimized heating rate and cooling rate are controlled between 5 and 10 ℃/min before and after pressureless sintering (in the following examples, the heating rate and the cooling rate are both 5 ℃/min).

The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.

Example 1:

s1: according to the Shanghai university of transportation, a micron-sized layer-shaped pore structure yttria-stabilized zirconia ceramic foam material and a preparation method thereof, CN202110438410.4]The experimental method of example 1 was used to prepare a 3 mol% yttria-stabilized zirconia ceramic body with micron-scale porosity; the difference is only that: in this example, the volume of water in step 1) of patent example 1 was adjusted so that Y was contained in the obtained preliminary mixed suspension ₂ O ₃ +ZrO ₂ The solid content of the nano powder is 15 vol%;

s2: dipping a phenolic resin solution (CAS No. 9003-35-4) with the mass concentration of 85% into an yttria-stabilized zirconia ceramic blank by adopting a vacuum stirring defoaming machine under the conditions that the vacuum degree is 5Pa, the dipping time is 6min and the dipping temperature is room temperature, wherein the mass ratio of the yttria-stabilized zirconia ceramic blank to the phenolic resin is 1.7, heating and curing the yttria-stabilized zirconia ceramic blank for 1h at the temperature of 110 ℃, and then carrying out heat treatment for 2h at the temperature of 1100 ℃ in a high-purity argon atmosphere to obtain a mixture of 3YSZ and carbon;

s3: placing the mixture in a hot pressing furnace, pressureless sintering at 1850 ℃ for 2h, and cooling with the furnace to obtain the zirconium carbide coated zirconia ceramic foam material (the porosity is about 83%, the interlayer spacing is about 16.5 μm, and the wall thickness is about 4.5 μm).

The ceramic foam material was characterized as follows:

FIG. 1 is a macroscopic view of the ceramic foam, and it can be seen that the foam appears black in appearance.

FIG. 2 is a scanning electron microscope (in the figure, black parts are embedded resin, and gray parts are ceramic) of the cross section of the ceramic foam material along the growth direction of ice crystals after vacuum embedding. The statistics of a plurality of electron micrographs show that the average pore wall thickness is about 4.5 μm and the average pore spacing is about 16.5 μm. FIG. 3 is an enlarged view of FIG. 2 at the white frame, showing that the inside of the pore wall is sintered more densely. Fig. 4 is a surface scanning energy spectrum diagram of each element at a white frame of fig. 2, a white pixel point represents the corresponding element, and it can be seen from the diagram that Y and O elements are enriched in the middle, and C elements are enriched on both sides, so that the obtained material is a zirconium oxide outer layer coated with a layer of zirconium carbide.

FIG. 5 is a scanning electron microscope image of a longitudinal section of the ceramic foam.

Example 2:

a zirconium carbide coated zirconia ceramic foam, the preparation method of which differs from that of example 1 only in that: in step S2, the phenolic resin used has a mass concentration of 80%.

The resulting ceramic foam had a porosity of about 83%, a layer spacing of about 16.5 μm, and a wall thickness of about 4.5. mu.m.

A pure zirconium carbide foam material is prepared by the following steps: the preparation method comprises the steps of preparing a porous zirconium carbide green body by using 100-300nm zirconium carbide powder (CY-ZrClVA, Jilin Changyu Tetao new material technology Co., Ltd.) with the solid content of initial slurry of 15 vol% by using the same directional solidification method (see step 3 of example 1 in CN202110438410.4), sintering at 1850 ℃ without pressure for 2h, and cooling along with a furnace to obtain a pure zirconium carbide foam material.

The ceramic foam material was characterized as follows:

FIG. 6 shows a comparison of the compressive stress-strain curve of the zirconium carbide-coated zirconia ceramic foam and the pure zirconium carbide foam in this example, wherein the testing apparatus is a universal material testing machine (Z20), the testing standard is ASTM C1424-04, the sample size is 10X 3mm, the testing speed is 0.5mm/min, and 5 samples are tested with regularity. It can be seen from the figure that the compressive strength of the ceramic foam material of the embodiment in the direction perpendicular to the normal line of the sheet layer can reach 15.2MPa, which is significantly higher than that of the nano zirconium carbide green body prepared by the same directional solidification process, and the compressive strength (4.4 MPa) of the zirconium carbide ceramic foam with the porosity of 83% is obtained after sintering at the same temperature. Also higher than the compressive strength (-10.2 MPa) of yttria stabilized zirconia foam ceramics with a porosity of 77.7% (see patent CN 202110438410.4).

FIG. 7 shows the thermal conductivity of the ceramic foam and pure zirconium carbide foam of this example at 100-900 ℃ perpendicular to the normal direction of the sheets (the thermal conductivity test method is laser flash (LFA 427, Netzsch), the test conditions are under argon protection, the sample is a square with a side length of 10mm, the sample thickness of the ceramic foam is 1.38mm, and the sample thickness of the pure zirconium carbide foam is 2.10mm), and the test standard is ASTM E1461. As can be seen from the figure, the thermal conductivity of the zirconium carbide coated zirconia ceramic foam material is 1.9-2.5W/(m.K) between room temperature and 800 ℃, and is slightly higher than that of pure zirconium carbide foam (1.2-1.5W/(m.K)) sintered at the same temperature and with the same porosity and similar layered structure. The thermal conductivity of the composite ceramic foam is 0.567W/(m.K) at 800-900 ℃, and is equivalent to that of a pure zirconium carbide foam material.

Example 3:

s1: according to the Shanghai university of transportation, a micron-sized layer-shaped pore structure yttria-stabilized zirconia ceramic foam material and a preparation method thereof, CN202110438410.4]The experimental method of example 1 was used to prepare a 3YSZ ceramic body with micron level porosity. The difference is only that: in this example, the volume of water in step 1) of patent example 1 was adjusted so that Y was contained in the obtained preliminary mixed suspension ₂ O ₃ +ZrO ₂ The solid content of the nano powder is 20 vol%;

s2: soaking a phenolic resin solution with the mass concentration of 80% into an yttria-stabilized zirconia ceramic blank by adopting a vacuum stirring defoaming machine under the conditions of the vacuum degree of 5Pa, the soaking time of 6min and the room temperature, wherein the mass ratio of the yttria-stabilized zirconia ceramic blank to the phenolic resin solution is 1.7, heating and curing the yttria-stabilized zirconia ceramic blank at 110 ℃ for 1h, and then carrying out heat treatment at 1100 ℃ for 2h in a high-purity argon atmosphere to obtain a mixture of 3YSZ and carbon;

s3: and placing the mixture in a hot pressing furnace, sintering the mixture for 2 hours at 1850 ℃ without pressure, and cooling the mixture along with the furnace to obtain the zirconium carbide coated zirconia ceramic foam material.

The final ceramic foam had a porosity of about 79%, a layer spacing of about 14.1 μm, and a wall thickness of about 10.4 μm. This example is achieved by increasing Y ₂ O ₃ +ZrO ₂ The solid content of the nano powder reduces the porosity, increases the wall thickness and reduces the interlayer spacing.

The ceramic foam material was characterized as follows:

FIG. 8 is a compressive stress-strain curve of the ceramic foam, showing that the compressive strength of the material reaches 14.3MPa, which is measured in the same manner as example 2.

Example 4:

compared with the example 3, the preparation method of the zirconium carbide coated zirconia ceramic foam material only differs from that of the example 3 in that: in step S3, the pressureless sintering temperature is 1700 ℃.

The final ceramic foam had a porosity of about 79%, a layer spacing of about 13.2 μm, and a wall thickness of about 9.5 μm.

The ceramic foam material was characterized as follows:

FIG. 9 is a compressive stress-strain curve of the ceramic foam, showing that the compressive strength of the material reaches 16.3MPa, which is measured in the same manner as example 2.

In conclusion, the zirconium carbide coated zirconia ceramic foam material prepared by the invention has the advantages of compact sintering, low thermal conductivity, high strength and good heat insulation performance, and has great application potential on ultrahigh-speed aircrafts.

The embodiments described above are described to facilitate an understanding and use of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make modifications and alterations without departing from the scope of the present invention.

Claims

1. A preparation method of zirconium carbide coated zirconia ceramic foam material is characterized by comprising the following steps:

s1: preparing a zirconia ceramic body with micron-level pores and stabilized by yttria;

s2: adopting phenolic resin to vacuum-impregnate the yttria-stabilized zirconia ceramic blank with micron-level pores, and obtaining a zirconia/carbon ceramic foam precursor after heating resin curing and high-temperature roasting heat treatment in an inert atmosphere or a reducing atmosphere;

s3: and carrying out pressureless sintering on the YSZ/C ceramic foam precursor to obtain the zirconium carbide coated zirconia ceramic foam material.

2. The method of claim 1, wherein in step S1, with reference to CN202110438410.4, a yttria-stabilized zirconia ceramic body with micron-scale pores is prepared.

3. The method for preparing zirconium carbide coated zirconium oxide ceramic foam material according to claim 2, wherein Y is used ₂ O ₃ +ZrO ₂ In the nano-powder, Y ₂ O ₃ The molar content of (a) is 1 to 5 mol%.

4. The method of claim 1, wherein in step S2, the phenolic resin is mixed with the yttria-stabilized zirconia ceramic body with micron-scale pores in the form of a phenolic resin solution with a mass fraction of 70-90%.

5. The method of claim 1, wherein in step S2, the mass ratio of the yttria-stabilized zirconia ceramic body with micron-scale pores to the phenolic resin solution is not more than 1.7.

6. The method of claim 1, wherein in step S2, the vacuum degree is 5-8Pa, the dipping time is 6-10min, and the dipping temperature is room temperature.

7. The method of claim 1, wherein the heating temperature is 90-130 ℃ and the heating time is 0.5-1.5h in the step S2.

8. The method as claimed in claim 1, wherein in step S2, the heat treatment temperature is 900-1200 ℃ and the heat treatment time is 1-4 h; the inert gas is argon, nitrogen or H ₂ One kind of mixed gas of Ar and Ar.

9. The method as claimed in claim 1, wherein in step S3, the sintering temperature is 1600-1900 ℃ and the sintering time is 1-3 h.

10. A zirconium carbide coated zirconia ceramic foam produced by the method of any one of claims 1 to 9.