Preparation method and application of ZrB2 / ZrC / SiC complex-phase precursor material with high ceramic yield

Abstract

The invention discloses a preparation method of a ZrB2 / ZrC / SiC complex-phase precursor material with high ceramic yield, which is specifically implemented according to the following steps: step 1, in an inert atmosphere, polymerizing zirconium acetylacetonate at a certain temperature, and converting into high-molecular zirconium-containing precursor zirconium polyacetylacetonate; adding a certain amount of boric acid into a polymer zirconium-containing precursor zirconium polyacetylacetonate, dissolving in a solvent, stirring at a constant temperature in a reflux condensation system in an inert atmosphere to obtain a homogeneous mixed solution, removing the solvent from the homogeneous mixed solution through rotary evaporation, and performing cross-linking curing to obtain a ZrB2 / ZrC precursor; and step 2, in an inert atmosphere, respectively dissolving the ZrB2 / ZrC precursor and polycarbosilane in a solvent, fully mixing, stirring at a constant temperature, removing the solvent, and carrying out cross-linking curing in the inert atmosphere to obtain the ZrB2 / ZrC / SiC precursor. The invention also discloses an application of the ZrB2 / ZrC / SiC precursor.

Description

Technical Field

[0001] The present invention belongs to the technical field of preparation methods of composite ceramic materials, and relates to a preparation method of a ZrB 2 / ZrC / SiC composite precursor material with a high ceramic yield; the present invention also relates to the application of the ZrB 2 / ZrC / SiC composite precursor material with a high ceramic yield prepared by the above method. Background Art

[0002] Silicon carbide (SiC) has a high melting point (2830 °C), high hardness (19.8 GPa), high strength (224 GPa), excellent high-temperature resistance, oxidation resistance, and corrosion resistance. In a high-temperature oxygen environment, it resists the erosion of corrosive gases by forming a dense SiO 2 film layer on the surface, and has broad application prospects in the fields of aerospace and so on. However, above 1700 °C, SiC will oxidize into gaseous SiO, resulting in a sharp increase in the surface ablation rate of the material and affecting its service life. Research by Aguirre et al. has shown that the introduction of transition metal elements (Zr, Hf, Ta, Ti) can improve its high-temperature oxidation resistance (Aguirre, T. G., Lamm, B. W., Cramer, C. L., Mitchell, D. J., Zirconium-diboride silicon-carbide composites: A review. Ceramics International 2022, 48 (6), 7344-7361.). Zirconium carbide (ZrC), zirconium boride (ZrB 2 ) are common transition metal carbides and borides, and have excellent properties that the structure and properties are not significantly damaged during the heating process below 3000 °C, and are considered to have great application value in the ultra-high temperature field. Preparing a ZrB 2 / ZrC / SiC ternary composite material can effectively improve the problem of insufficient oxidation resistance of a single SiC ceramic at high temperatures. ZrB 2 / ZrC / SiC three-phase ceramics can generate different stable oxide phases after oxidation at low, medium, and high temperatures (500~1000 °C: B 2 O 3 , 1300~1600 °C: SiO 2 , above 2000 °C: ZrO 2 ), showing excellent oxidation and ablation resistance in a wide temperature range, which is of great significance in the applications in the fields of aerospace and so on. Therefore, there is an urgent need to develop an efficient and simple method for preparing ZrB 2 / ZrC / SiC ceramics.

[0003] Currently, ZrB2 The preparation of ZrB 2 / ZrC / SiC ceramics mainly includes precursor conversion method, sol-gel method, hydrothermal method, solid-state reaction method, etc. The sol-gel method requires a relatively long preparation period. The hydrothermal method is prone to generate a high oxidation state during the reaction, resulting in excessive oxygen content. The solid-state reaction method is difficult to obtain high-purity phases and cannot ensure the uniformity of the powder composition distribution. The precursor conversion method, with its advantages such as good purity control, composition uniformity, and low oxygen content, has become a relatively ideal choice in the preparation of ZrB 2 / ZrC / SiC ceramics. Chinese Patent CN119161584A discloses a method for preparing SiC / ZrC / ZrB 2 composite ceramics by the precursor conversion method. The precursor polyboron zirconium carbon silicon alkane (PBZCS) is synthesized through the polymerization reaction of organic monomers. The precursor reacts at high temperature to form SiC / ZrC / ZrB 3 ) 3 , realizing the effective doping of boron and zirconium elements in SiC. The boron and zirconium elements in the ceramic product account for 3.45wt.% and 5.73wt.% respectively, and the ceramic yields of its three examples are 51%, 61%, and 63% respectively. In the preparation process of polyboron zirconium carbon silicon alkane (PBZCS) in this patent, polyzirconium carbon silicon alkane (PZCS), trimethylamine borane monomer (B(NHCH 2 ), and xylene need to be placed in a high-purity nitrogen high-pressure reaction kettle for reaction, which has an explosion risk. Moreover, the reaction conditions of this system are relatively complex, involving multiple reaction processes. The temperature and time of the solvothermal reaction are relatively long, and the requirements for the selection of catalysts and reaction systems are relatively high. It requires a reaction of up to dozens of hours, with high process control requirements and a complex preparation process. In addition to SiC, ZrC, and ZrB 2 in the pyrolysis product of this precursor at 1600°C, there is also a ZrO 2 phase. The reaction temperature is high, and it is difficult to control the three-phase ratio. Therefore, it is urgent to develop a new preparation method for ZrB Summary of the Invention

[0004] The purpose of the present invention is to provide a preparation method for a ZrB 2 / ZrC / SiC composite precursor material with a high ceramic yield, which solves the problems of long reaction time, high reaction temperature, and low ceramic yield in the preparation of ZrB 2 / ZrC / SiC ceramics in the prior art.

[0005] The technical solution adopted by the present invention is a ZrB 2Preparation method of ZrB / ZrC / SiC composite precursor material, which is specifically implemented according to the following steps: Step 1, preparation of ZrB 2 / ZrC precursor Under an inert atmosphere, zirconium acetylacetonate is polymerized at a certain temperature to be converted into a high-molecular zirconium-containing precursor, polyzirconium acetylacetonate; then a certain amount of boric acid is added to the high-molecular zirconium-containing precursor polyzirconium acetylacetonate and dissolved in a solvent, and then stirred at a constant temperature in a condensation reflux system under an inert atmosphere to obtain a homogeneous mixed solution, and then the homogeneous mixed solution is removed of the solvent by rotary evaporation and crosslinked and cured to obtain ZrB 2 / ZrC precursor; Step 2, preparation of ZrB 2 / ZrC / SiC precursor Under an inert atmosphere, the ZrB 2 / ZrC precursor and polycarbosilane are respectively dissolved in a solvent and then fully mixed and stirred at a constant temperature, and then the solvent is removed and crosslinked and cured under an inert atmosphere to obtain ZrB 2 / ZrC / SiC precursor.

[0006] The feature of the present invention also lies in: In step 1, the polymerization temperature is 180 - 200 °C and the polymerization time is 70 - 90 min.

[0007] In step 1, the molar ratio of B to Zr in the mixture after adding boric acid to the high-molecular zirconium-containing precursor polyzirconium acetylacetonate is 3 - 12:1.

[0008] In step 1, the rotary evaporation temperature is 45 - 55 °C.

[0009] In step 1, the crosslinking and curing is: after the homogeneous mixed solution is removed of the solvent by rotary evaporation, it is kept at 190 - 210 °C in a drying oven for 1.5 - 2.5 h to obtain ZrB 2 / ZrC precursor.

[0010] In step 2, the mass ratio of polycarbosilane to ZrB 2 / ZrC precursor is 1:0.5 - 1.5.

[0011] In step 2, the crosslinking and curing is: in an inert atmosphere, it is heated from 5 - 10 °C / min to 250 - 400 °C and kept warm for 3 - 6 h.

[0012] The inert atmosphere in step 1 includes any one or a mixed gas of nitrogen and argon.

[0013] The solvent in step 1 is anhydrous ethanol, and the solvent in step 2 is xylene or tetrahydrofuran.

[0014] The second technical solution adopted by the present invention is the application of the prepared ZrB 2 / ZrC / SiC composite precursor material in the preparation of ZrB 2 / ZrC / SiC composite ceramics, specifically: under vacuum conditions, subject the prepared ZrB 2 / ZrC / SiC precursor to high-temperature pyrolysis treatment to obtain ZrB 2 / ZrC / SiC composite ceramic powder, specifically: Put the prepared ZrB 2 / ZrC / SiC precursor into a high-temperature pyrolysis furnace. In a vacuum environment, heat it from room temperature to 1100°C at a rate of 2 - 8°C / min, then heat it from 1100°C to 1300 - 1500°C at a rate of 2 - 5°C / min, hold for 2 - 4 h, then cool it from 1500°C to 1100°C at a rate of 2 - 5°C / min, then cool it from 1100°C to 200°C at a rate of 2 - 8°C / min, and finally cool it to room temperature with the furnace to obtain ZrB 2 / ZrC / SiC composite ceramic powder.

[0015] The beneficial effects of the present invention are: The ZrB 2 / ZrC / SiC precursor of the present invention is prepared by reacting zirconium acetylacetonate, boric acid, and polycarbosilane as zirconium source, boron source, and silicon source respectively under an inert atmosphere. Zirconium acetylacetonate as the zirconium source only generates acetylacetonate ligands during the polymerization process, with relatively low reactivity, reducing unnecessary side reactions and improving the reaction efficiency. When using the ZrB 2 / ZrC / SiC precursor of the present invention for pyrolysis to prepare ceramics, compared with the prior art, the reaction time and reaction temperature are reduced, and the ceramic yield is increased.

[0016] By adjusting the ratios of different zirconium source, boron source, and silicon source, the present invention realizes the adjustable ratio of the three components of ZrB 2 / ZrC / SiC composite ceramics.

[0017] The preparation process of the present invention is simple, with a short preparation cycle, no need to introduce additional carbon source, low cost, the obtained ZrB 2 / ZrC / SiC composite ceramics have uniform element distribution, which is obtained by sem-eds mapping, showing high distribution and ceramic yield. Description of the Drawings

[0018] Figure 1 is the thermogravimetric differential thermal diagram of the ZrB 2 / ZrC / SiC precursor obtained in Example 1 of the present invention under argon; Figure 2 is the ZrB obtained in Example 1 of the present invention 2XRD diffraction pattern of ZrB Figure 3 / ZrC / SiC composite ceramic powder obtained in Example 1 of the present invention 2 SEM-EDS diagram of ZrB Detailed implementation manners

[0019] The present invention will be described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0020] The preparation method of the ZrB 2 / ZrC / SiC composite precursor material with high ceramic yield of the present invention is specifically implemented according to the following steps: Step 1, Preparation of ZrB 2 / ZrC precursor Under an inert atmosphere, zirconium acetylacetonate is polymerized at a certain temperature. The polymerization temperature is 180 - 200 °C, and the polymerization time is 70 - 90 min. Zirconium acetylacetonate is converted into a high-molecular zirconium-containing precursor, polyzirconium acetylacetonate; then a certain amount of boric acid (the molar ratio of B to Zr is 3 - 12:1) is added to the high-molecular zirconium-containing precursor polyzirconium acetylacetonate and dissolved in absolute ethanol. Then, under an inert atmosphere (any one or a mixed gas of nitrogen and argon), it is stirred at a constant temperature in a condensing reflux system to obtain a homogeneous mixed solution. Then, the homogeneous mixed solution is rotary evaporated at 45 - 55 °C to remove the solvent (absolute ethanol) and then kept at 190 - 210 °C in an oven for 1.5 - 2.5 h to obtain ZrB 2 / ZrC precursor; Step 2, Preparation of ZrB 2 / ZrC / SiC precursor Under an inert atmosphere (any one or a mixed gas of nitrogen and argon), polycarbosilane and ZrB 2 / ZrC precursor are weighed according to a mass ratio of 1:0.5 - 1.5. Then, polycarbosilane and ZrB 2 / ZrC precursor are respectively dissolved in xylene or tetrahydrofuran and then fully mixed and stirred at a constant temperature. Then, after removing the solvent (xylene or tetrahydrofuran), under an inert atmosphere, it is heated at 5 - 10 °C / min to 250 - 400 °C and kept at this temperature for 3 - 6 h to obtain ZrB 2 / ZrC / SiC precursor.

[0021] Step 3, The ZrB 2 / ZrC / SiC precursor prepared in Step 2 is ceramized to prepare ZrB 2 / ZrC / SiC composite ceramic powder, specifically: The prepared ZrB 2The ZrB 2 / ZrC / SiC precursor was placed in a high-temperature pyrolysis furnace. In a vacuum environment, it was heated to 1100 °C at a rate of 2 - 8 °C / min, then heated to 1300 - 1500 °C at a rate of 2 - 5 °C / min, held for 2 - 4 h, then cooled to 1100 °C at a rate of 2 - 5 °C / min, and subsequently cooled to 200 °C at a rate of 2 - 8 °C / min, and finally cooled to room temperature with the furnace to obtain ZrB

[0022] Example 1 Step 1. Preparation of ZrB 2 / ZrC precursor: Under an inert atmosphere, zirconium acetylacetonate (Zr(acac) 4 ) was polymerized at 190 °C for 90 min to obtain polyzirconium acetylacetonate; Boric acid with a B:Zr molar ratio of 10:1 was added, dissolved in absolute ethanol, mixed evenly under an argon atmosphere, and stirred at 80 °C for 6 h in a condensation reflux system to obtain a homogeneous mixed solution. Subsequently, the solvent was removed by low-temperature rotary evaporation at 50 °C and cross-linked at 200 °C for 2 h to obtain the ZrB 2 / ZrC precursor; Step 2. Preparation of ZrB 2 / ZrC / SiC precursor: The ZrB 2 / ZrC precursor and polycarbosilane (PCS) were separately dissolved in tetrahydrofuran at a mass ratio of 1:1 under an argon atmosphere and then mixed. The solvent was removed by stirring at 60 °C, and then cross-linked at 300 °C for 4.5 h under a nitrogen atmosphere to obtain the ZrB 2 / ZrC / SiC precursor; Step 3. Ceramization of the precursor: The precursor was placed under vacuum conditions, heated to 1400 °C at a rate of 3 °C / min, and pyrolyzed at high temperature for 2 h to obtain the ZrB 2 / ZrC / SiC composite ceramic powder. The XRD and SEM-EDS diagrams are shown in Figure 2 and 3 respectively; After detection, the proportions of B, C, O, Si, and Zr elements in the ZrB 2 / ZrC / SiC ceramic prepared in this example are 15.44 wt.%, 45.11 wt.%, 4.49 wt.%, 11.29 wt.%, and 23.67 wt.% respectively, and the oxygen content is low.

[0023] As Figure 1 shown in the thermogravimetric differential thermal diagram of the precursor under argon, it can be seen that the high ceramic yield of the precursor is 68.8%; as Figure 2As shown, it indicates that the low-temperature ceramized product of the precursor prepared in this example is only ZrB 2 , ZrC, and SiC, without other miscellaneous items, such as Figure 3 shown, indicating that the ZrB 2 / ZrC / SiC composite ceramic powder prepared in this example has a uniform element distribution and a low oxygen content.

[0024] Example 2 Step 1. Preparation of ZrB 2 / ZrC precursor: Under an inert atmosphere, zirconium acetylacetonate (Zr(acac) 4 ) was polymerized at 190 °C for 90 min to obtain polyzirconium acetylacetonate; Boric acid with a B:Zr molar ratio of 5:1 was added, dissolved in absolute ethanol, mixed evenly under an argon atmosphere, and stirred at 80 °C for 6 h in a condensation reflux system to obtain a homogeneous mixed solution. Subsequently, the solvent was removed by low-temperature rotary evaporation at 50 °C and cross-linked at 200 °C for 2 h to obtain the ZrB 2 / ZrC precursor; Step 2. Preparation of ZrB 2 / ZrC / SiC precursor: The ZrB 2 / ZrC precursor and polycarbosilane (PCS) were respectively dissolved in tetrahydrofuran at a mass ratio of 1:1 under an argon atmosphere and then mixed. The solvent was removed by stirring at 60 °C, and then cross-linked at 300 °C for 4 h under a nitrogen atmosphere to obtain the ZrB 2 / ZrC / SiC precursor; Step 3. Ceramization of the precursor: The precursor was placed under vacuum conditions, heated to 1300 °C at a rate of 6 °C / min, and pyrolyzed at high temperature for 2 h to obtain the ZrB 2 / ZrC / SiC composite ceramic powder, with a ceramic yield of 65.8%.

[0025] Example 3 Step 1. Preparation of ZrB 2 / ZrC precursor: Under an inert atmosphere, zirconium acetylacetonate (Zr(acac) 4 ) was polymerized at 190 °C for 80 min to obtain polyzirconium acetylacetonate; Boric acid with a B:Zr molar ratio of 8:1 was added, dissolved in absolute ethanol, mixed evenly under an argon atmosphere, and stirred at 90 °C for 5 h in a condensation reflux system to obtain a homogeneous mixed solution. Subsequently, the solvent was removed by low-temperature rotary evaporation at 50 °C and cross-linked at 200 °C for 2 h to obtain the ZrB 2 / ZrC precursor; Step 2. ZrB2 Preparation of ZrB / ZrC / SiC precursor: 2 The ZrB 2 / ZrC precursor and polycarbosilane (PCS) were separately dissolved in xylene at a mass ratio of 1:1 under a nitrogen atmosphere and then mixed. The solvent was removed by stirring at 60 °C, and then crosslinked at 300 °C for 4 h under a nitrogen atmosphere to obtain the ZrB Step 3. Ceramization of the precursor: The precursor was placed under vacuum conditions and heated to 1400 °C at a rate of 5 °C / min, followed by high-temperature pyrolysis for 4 h to obtain ZrB 2 / ZrC / SiC composite ceramic powder with a ceramic yield of 67.6%.

[0026] Example 4 Step 1. Preparation of ZrB 2 / ZrC precursor: Under an inert atmosphere, zirconium acetylacetonate (Zr(acac) 4 ) was polymerized at 190 °C for 70 min to obtain polyzirconium acetylacetonate; Boric acid with a B:Zr molar ratio of 10:1 was added, dissolved in absolute ethanol, mixed evenly under an argon atmosphere, and stirred at 90 °C for 6 h in a condensing reflux system to obtain a homogeneous mixed solution. Subsequently, the solvent was removed by low-temperature rotary evaporation at 50 °C and crosslinked at 200 °C for 2.5 h to obtain the ZrB 2 / ZrC precursor; Step 2. Preparation of ZrB 2 / ZrC / SiC precursor: The ZrB 2 / ZrC precursor and polycarbosilane (PCS) were separately dissolved in tetrahydrofuran at a mass ratio of 0.5:1 under a nitrogen atmosphere and then mixed. The solvent was removed by stirring at 60 °C, and then crosslinked at 300 °C for 5 h under a nitrogen atmosphere to obtain the ZrB 2 / ZrC / SiC precursor; Step 3. Ceramization of the precursor: The precursor was placed under vacuum conditions and heated to 1400 °C at a rate of 2 °C / min, followed by high-temperature pyrolysis for 2 h to obtain ZrB 2 / ZrC / SiC composite ceramic powder with a ceramic yield of 65.1%.

[0027] Example 5 Step 1. Preparation of ZrB 2 / ZrC precursor: Under an inert atmosphere, zirconium acetylacetonate (Zr(acac) 4(0) Polymerize at 190 °C for 90 min to obtain zirconium acetylacetonate polymer; Add boric acid with a B / Zr molar ratio of 9:1, dissolve it in absolute ethanol, mix evenly under an argon atmosphere, and stir in a reflux condenser system at 70 °C for 6 h to obtain a homogeneous mixed solution. Subsequently, remove the solvent by low-temperature rotary evaporation at 50 °C and crosslink at 200 °C for 1.5 h to obtain the ZrB 2 / ZrC precursor; Step 2. Preparation of the ZrB 2 / ZrC / SiC precursor: Dissolve the ZrB 2 / ZrC precursor and polycarbosilane (PCS) in tetrahydrofuran at a mass ratio of 1:1 under a nitrogen atmosphere and then mix them. Stir at 60 °C to remove the solvent, and then crosslink at 300 °C for 5 h under a nitrogen atmosphere to obtain the ZrB 2 / ZrC / SiC precursor; Step 3. Ceramization of the precursor: Place the precursor under vacuum conditions, heat it to 1500 °C at a rate of 8 °C / min, and pyrolyze at high temperature for 2 h to obtain the ZrB 2 / ZrC / SiC composite ceramic powder with a ceramic yield of 67.3%.

[0028] Example 6 Step 1. Preparation of the ZrB 2 / ZrC precursor: Under an inert atmosphere, polymerize zirconium acetylacetonate (Zr(acac) 4 ) at 190 °C for 80 min to obtain zirconium acetylacetonate polymer; Add boric acid with a B / Zr molar ratio of 5:1, dissolve it in absolute ethanol, mix evenly under an argon atmosphere, and stir in a reflux condenser system at 70 °C for 4 h to obtain a homogeneous mixed solution. Subsequently, remove the solvent by low-temperature rotary evaporation at 50 °C and crosslink at 200 °C for 1.5 h to obtain the ZrB 2 / ZrC precursor; Step 2. Preparation of the ZrB 2 / ZrC / SiC precursor: Dissolve the ZrB 2 / ZrC precursor and polycarbosilane (PCS) in tetrahydrofuran at a mass ratio of 1.5:1 under a nitrogen atmosphere and then mix them. Stir at 60 °C to remove the solvent, and then crosslink at 300 °C for 5 h under a nitrogen atmosphere to obtain the ZrB 2 / ZrC / SiC precursor; Step 3. Ceramization of the precursor: The precursor was placed under vacuum conditions and heated to 1300 °C at a rate of 6 °C / min, followed by high-temperature pyrolysis for 3 h to obtain ZrB 2 / ZrC / SiC composite ceramic powder with a ceramic yield of 64.6%.

Claims

1. A method for preparing a ZrB2 / ZrC / SiC composite precursor material with high ceramic yield, characterized in that: The specific steps are as follows: Step 1, preparation of ZrB2 / ZrC precursor In an inert atmosphere, zirconium acetylacetonate is polymerized at a certain temperature to be converted into a polymer zirconium-containing precursor polyacetylacetonate zirconium; a certain amount of boric acid is then added to the polymer zirconium-containing precursor polyacetylacetonate zirconium and dissolved in a solvent; then, a homogeneous mixed solution is obtained by constant temperature stirring in a condensation reflux system under an inert atmosphere; then, the homogeneous mixed solution is subjected to rotary evaporation to remove the solvent and then cross-linked and cured to obtain a ZrB2 / ZrC precursor; Step 2, preparation of ZrB2 / ZrC / SiC precursor Under an inert atmosphere, the ZrB2 / ZrC precursor and polycarbosilane are dissolved in a solvent respectively, fully mixed and stirred at a constant temperature, and then the solvent is removed and cross-linked and cured under an inert atmosphere to obtain a ZrB2 / ZrC / SiC precursor.

2. The method for preparing a ZrB2 / ZrC / SiC multiphase precursor material with high ceramic yield according to claim 1, characterized in that: In the step 1, the polymerization temperature is 180-200° C., and the polymerization time is 70-90 min.

3. The method for preparing a ZrB2 / ZrC / SiC multiphase precursor material with high ceramic yield according to claim 1, characterized in that: In the step 1, the molar ratio of B to Zr in the mixture after adding boric acid to the polymer zirconium-containing precursor polyacetylacetonate zirconium is 3-12:

1.

4. The method for preparing a ZrB2 / ZrC / SiC multiphase precursor material with high ceramic yield according to claim 1, characterized in that: The rotary evaporation temperature in step 1 is 45-55°C.

5. The method for preparing a ZrB2 / ZrC / SiC multiphase precursor material with high ceramic yield according to claim 1, characterized in that: The cross-linking and curing in step 1 is as follows: the homogeneous mixed solution is subjected to rotary evaporation to remove the solvent and then kept in a drying oven at 190-210° C. for 1.5-2.5 hours to obtain a ZrB2 / ZrC precursor.

6. The method for preparing a ZrB2 / ZrC / SiC multiphase precursor material with high ceramic yield according to claim 1, characterized in that: In step 2, the mass ratio of polycarbosilane to ZrB2 / ZrC precursor is 1:0.5-1.

5.

7. The method for preparing a ZrB2 / ZrC / SiC multiphase precursor material with high ceramic yield according to claim 1, characterized in that: The cross-linking curing in step 2 is as follows: in an inert atmosphere, the temperature is raised to 250-400° C. at a rate of 5-10° C. / min and the temperature is kept for 3-6 hours.

8. The method for preparing a ZrB2 / ZrC / SiC multiphase precursor material with high ceramic yield according to claim 1, characterized in that: The inert atmosphere in step 1 includes any one of nitrogen and argon or a mixed gas.

9. The method for preparing a ZrB2 / ZrC / SiC multiphase precursor material with high ceramic yield according to claim 1, characterized in that: The solvent in step 1 is anhydrous ethanol, and the solvent in step 2 is xylene or tetrahydrofuran.

10. Application of the ZrB2 / ZrC / SiC composite precursor material prepared according to any one of claims 1 to 9 in the preparation of ZrB2 / ZrC / SiC composite ceramics, specifically: subjecting the prepared ZrB2 / ZrC / SiC precursor to high-temperature pyrolysis treatment under vacuum conditions to obtain ZrB2 / ZrC / SiC composite ceramic powder, specifically: The prepared ZrB2 / ZrC / SiC precursor is placed in a high-temperature pyrolysis furnace, and in a vacuum environment, the temperature is increased to 1100°C at 2-8°C / min, then increased to 1300-1500°C at 2-5°C / min, kept warm for 2-4h, then cooled to 1100°C at 2-5°C / min, then cooled to 200°C at 2-8°C / min, and finally cooled to room temperature with the furnace to obtain ZrB2 / ZrC / SiC composite ceramic powder.

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