Composite ferrite ceramic material, wave-absorbing ceramic coating capable of being thermally sprayed and preparation method of wave-absorbing ceramic coating

Abstract

The invention provides a composite ferrite ceramic material. The composite ferrite ceramic material is prepared from lanthanum oxide and ferric oxide through solid-phase sintering, the mass ratio of lanthanum oxide to ferric oxide is 0.5: (6-8). The invention designs a composite ferrite ceramic material with specific composition and proportion, and prepares a composite ceramic coating. According to the invention, the addition amount of ferric oxide is greatly increased, so that the overall performance of the composite ferrite ceramic material is improved. According to the invention, an atmosphere plasma spraying method is adopted, a specific chemical reaction process is utilized to introduce a hard magnetic material, the magnetic loss of the wave-absorbing coating to electromagnetic waves is improved, the component of the coating is composite ceramic and has certain high-temperature resistance, and the high-temperature-resistant composite ceramic coating with the wave-absorbing function is obtained. The composite ferrite ceramic material provided by the invention can be used as a wave-absorbing agent to be applied to a thermal barrier ceramic coating, and is suitable for national defense and military industry.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of wave-absorbing ceramic materials, and relates to a composite ferrite ceramic material, a wave-absorbing ceramic coating and a preparation method thereof, in particular to a composite ferrite ceramic material, a heat-spraying wave-absorbing ceramic coating and a preparation method thereof. BACKGROUND

[0002] The thermal barrier ceramic coating (TBC) is widely applied to the fields of aerospace and military equipment due to its good wear resistance, high-temperature resistance and heat insulation, and the ability to maintain stable performance in harsh environments such as high temperature, high pressure and high speed. With the continuous development of modern technology, the demand for TBCs with wave-absorbing function is increasing, which can not only enhance the temperature resistance, heat insulation and wear resistance of high-temperature components to prolong their service life, but also reduce the probability of being detected by ground radar, play a role in stealth and anti-interference, and thus enhance the survival and combat effectiveness of aircraft and weapon equipment.

[0003] The thermal barrier ceramic coating is usually prepared by atmospheric plasma spraying process. Under the super-high temperature flame, the ceramic material is rapidly melted and deposited on the surface of the substrate to form a coating, which can well inherit the high-temperature resistance, heat insulation and wear resistance of the original material. However, traditional wave-absorbing materials cannot be prepared by such flame spraying or other high-temperature forming processes, because they will be oxidized or decomposed at high temperatures, resulting in the attenuation or loss of their wave-absorbing performance. Therefore, the coating is usually prepared by brushing or pasting, which greatly limits the application of wave-absorbing materials in thermal barrier ceramic coatings.

[0004] Therefore, how to find a more suitable way to broaden the preparation method of wave-absorbing ceramic coatings and reduce the corresponding restrictions has become one of the problems to be solved by many forward-looking researchers in the industry. SUMMARY

[0005] Therefore, the technical problem to be solved by the application is to provide a composite ceramic material, a wave-absorbing ceramic coating and a preparation method thereof, in particular a composite ferrite ceramic material and a heat-spraying wave-absorbing ceramic coating. The application designs a new type of ferrite ceramic material with wave-absorbing performance. After the ceramic coating is prepared by atmospheric plasma spraying technology, the stability of the ferrite structure can still be maintained, and the wave-absorbing performance is also well inherited. Therefore, it can be used as a ceramic material with wave-absorbing function in the thermal barrier coating.

[0006] The application provides a composite ferrite ceramic material, which is obtained by solid-phase sintering of lanthanum oxide and ferric oxide.

[0007] The mass ratio of the lanthanum oxide to the ferric oxide is 0.5:(6-8).

[0008] Preferably, the temperature of the solid phase sintering is 1351-1450 DEG C.

[0009] The time of the solid phase sintering is 3-6 hours.

[0010] Preferably, the solid phase sintering is specifically solid phase sintering under a protective atmosphere.

[0011] The composite ferrite ceramic material contains ferric oxide.

[0012] The application provides a wave-absorbing ceramic coating, which comprises, in terms of mass fractions of raw materials:

[0013] Composite ferrite ceramic material 95-98 parts by weight;

[0014] Granulating agent 0.5-1 part by weight;

[0015] Binder 1-3 parts by weight;

[0016] Solvent;

[0017] The composite ferrite ceramic material comprises the composite ceramic material in any one of the above technical solutions.

[0018] Preferably, the granulating agent comprises ammonium citrate;

[0019] The binder comprises one or more of gum arabic, PVA, PEO, PEG, cellulose and EVA;

[0020] The solvent comprises water.

[0021] 6. A preparation method of the wave-absorbing ceramic coating in any one of the above technical solutions, comprising the following steps:

[0022] 1) After the composite ferrite ceramic material, the granulating agent, the binder and the solvent are mixed, spray granulation is performed to obtain raw material particles;

[0023] 2) The raw material particles obtained in the above step are deposited on a substrate after air plasma spraying to obtain the wave-absorbing ceramic coating.

[0024] Preferably, the mixing mode comprises ball milling mixing.

[0025] The mixing time is 20-40 hours.

[0026] The particle size of the raw material particles is 20-120 microns.

[0027] Preferably, the temperature of the atmospheric plasma spraying is greater than or equal to 8000 DEG C.

[0028] The power of the atmospheric plasma spraying is 35-40 kw.

[0029] Preferably, the spraying distance of the atmospheric plasma spraying is 80-120 mm.

[0030] The powder feeding amount of the atmospheric plasma spraying is 10-20 g / min.

[0031] Preferably, the plasma gas of the atmospheric plasma spraying comprises argon and hydrogen.

[0032] The flow of the carrier gas of the atmospheric plasma spraying is 2.5-3.0 SLPM.

[0033] The application provides a composite ferrite ceramic material, which is obtained by solid-phase sintering of lanthanum oxide and ferric oxide; the mass ratio of the lanthanum oxide to the ferric oxide is 0.5:(6-8). Compared with the prior art, the application avoids the problems of decomposition of ferrite material or oxidation of carbon material, which are caused by the difficulty of using flame or high-temperature forming process to prepare the existing wave-absorbing ceramic coating. The application researches that the atmospheric plasma spraying (APS) is a surface strengthening and surface modification technology, which is used for preparing a coating with properties of wear resistance, corrosion resistance, high-temperature oxidation resistance, electrical insulation and the like, so as to improve the performance of the base material and expand the application scenarios. The APS technology has three unique advantages: the super-high-temperature property can quickly melt raw materials, the spraying speed is fast, the coating is dense and has good bonding performance, and the inert gas environment is not easy to oxidize the sprayed material. In the spraying process, the sprayed particles are only melted by the flame and deposited into the coating, and only physical changes occur without chemical reactions, so that the properties of the sprayed raw materials are maintained. However, the atmospheric plasma spraying also has the problem of decomposition of ferrite material when used for preparing the wave-absorbing ceramic coating.

[0034] Based on this, the application particularly designs a composite ferrite ceramic material with a specific composition and ratio, and prepares a composite ceramic coating, and the application greatly increases the addition amount of ferroferric oxide, thereby improving the overall performance of the composite ferrite ceramic material. The application also changes the conventional usage of the atmospheric plasma spraying process without chemical reaction, introduces a hard magnetic material by using a specific chemical reaction process, improves the magnetic loss of the electromagnetic wave of the wave-absorbing coating, and the composition of the coating is a composite ceramic with certain high-temperature resistance, thereby obtaining a composite ceramic coating with high-temperature resistance and wave-absorbing function. The application can synthesize a ceramic material with complex multiple components under the condition of high-temperature solid-phase synthesis in the air isolation condition, and can still maintain the structural stability after spray granulation and atmospheric plasma spraying, so that the wave-absorbing performance is well inherited, and the difficulty that the traditional wave-absorbing material cannot be subjected to thermal spraying is solved. Therefore, the composite ferrite ceramic material provided by the application can be applied to thermal barrier ceramic coatings as a wave-absorbing agent, and contributes to the national defense and military industry.

[0035] In the process of synthesizing the thermal barrier ceramic material, an excess amount of Fe2O3 raw material is added to introduce the magnetic element Fe, and then solid-phase synthesis is performed, and a composite ceramic coating with wave-absorbing performance and high-temperature resistance is prepared by particularly combining plasma spraying. The composite ceramic material with a specific composition and ratio provided by the application obtains ceramic particles after granulation, is deposited on a substrate after atmospheric plasma spraying, the main component of the coating is changed by chemical reaction of LaFeO3, and the high temperature and oxygen-deficient environment in the atmospheric plasma spraying process can further promote the reaction. In the application, the main component of the coating material is changed after the APS process, the content of Fe2O3 in the batching is high, which is beneficial to improving the synthesis efficiency of the ceramic material, and the concentration of the wave-absorbing material can be greatly improved after atmospheric plasma spraying, thereby exhibiting good wave-absorbing performance.

[0036] The production process of the thermal barrier ceramic coating provided by the application, i.e., the solid-phase synthesis method and the plasma spraying method, directly prepares a composite ceramic coating with wave-absorbing function. The application solves the shackles that the conventional ferrite cannot adopt the plasma spraying process, avoids the high temperature in the spraying process, which can cause the decomposition of the conventional ferrite and cause the disappearance of the magnetic property and wave-absorbing performance, and makes the plasma spraying process as a key process for forming the wave-absorbing agent in the application. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 The XRD graph of the composite ceramic material and the composite ceramic coating prepared in Example 1 of the application;

[0038] Figure 2 The electromagnetic wave reflection loss graph of the composite ceramic material prepared in Example 1 of the application;

[0039] Figure 3 The electromagnetic wave reflection loss graph of the composite ceramic coating prepared in Example 1 of the present application;

[0040] Figure 4 The hysteresis loop graph of the composite ceramic coating and the ceramic material prepared in Example 1 of the present application. DETAILED DESCRIPTION

[0041] In order to further understand the present application, the preferred embodiments of the present application are described below in conjunction with the examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present application, and are not limitations to the claims of the present application.

[0042] All raw materials of the present application are not particularly limited in source, and can be purchased on the market or prepared according to the conventional methods well known to those skilled in the art.

[0043] All raw materials of the present application are not particularly limited in purity, and the analytical pure or the conventional purity used in the field of thermal barrier ceramic material preparation is preferred in the present application.

[0044] All raw materials of the present application are not particularly limited in purity, and the analytical pure or the conventional purity used in the field of thermal barrier ceramic material preparation is preferred in the present application.

[0045] The present application provides a composite ferrite ceramic material, which is obtained by solid phase sintering of lanthanum oxide and ferric oxide.

[0046] The mass ratio of the lanthanum oxide to the ferric oxide is 0.5:(6-8).

[0047] In the present application, the mass ratio of the lanthanum oxide to the ferric oxide is 0.5:(6-8), which can be 0.5:(6.4-7.6), or 0.5:(6.8-7.2).

[0048] In the present application, the temperature of the solid phase sintering is preferably 1351-1450℃, more preferably 1370-1430℃, and more preferably 1390-1410℃.

[0049] In the present application, the time of the solid phase sintering is preferably 3-6 hours, more preferably 3.5-5.5 hours, and more preferably 4-5 hours.

[0050] In the present application, the solid phase sintering is particularly preferably performed under a protective atmosphere.

[0051] In the present application, the composite ferrite ceramic material preferably contains ferric oxide. Specifically, the composite ferrite ceramic material is particularly added with excess ferric oxide in the raw material.

[0052] In the present application, the composite ferrite ceramic material is sintered only by lanthanum oxide and ferric oxide, and does not contain other raw materials and elements.

[0053] The present application provides a wave-absorbing ceramic coating, which comprises, in terms of mass fraction of raw materials:

[0054] Composite ferrite ceramic material 95-98 parts by weight;

[0055] Granulating agent 0.5-1 parts by weight;

[0056] Binder 1-3 parts by weight;

[0057] Solvent;

[0058] The composite ferrite ceramic material comprises the composite ceramic material of any one of the above technical solutions.

[0059] In the present application, the composite ferrite ceramic material is added in an amount of 95-98 parts by weight, which can be 95.5-97.5 parts by weight, or 96-97 parts by weight.

[0060] In the present application, the granulating agent is added in an amount of 0.5-1 parts by weight, which can be 0.6-0.9 parts by weight, or 0.7-0.8 parts by weight.

[0061] In the present application, the binder is added in an amount of 1-3 parts by weight, which can be 1.4-2.6 parts by weight, or 1.8-2.2 parts by weight.

[0062] In the present application, the granulating agent preferably comprises ammonium citrate.

[0063] In the present application, the binder preferably comprises one or more of gum arabic, PVA, PEO, PEG, cellulose and EVA, and more preferably gum arabic, PVA, PEO, PEG, cellulose or EVA.

[0064] In the present application, the solvent preferably comprises water.

[0065] The present application provides a preparation method of the wave-absorbing ceramic coating of any one of the above technical solutions, comprising the following steps:

[0066] 1) After mixing the composite ferrite ceramic material, the granulating agent, the binder and the solvent, spray granulation is performed to obtain raw material particles;

[0067] 2) depositing the raw material particles obtained in the above step on a substrate after air plasma spraying, to obtain a wave-absorbing ceramic coating.

[0068] The present application first mixes the composite ferrite ceramic material, granulating agent, binder and solvent, and then sprays and granulates to obtain raw material particles.

[0069] In the present application, the mixing method preferably includes ball milling.

[0070] In the present application, the mixing time is preferably 20-40 hours, more preferably 24-36 hours, and more preferably 28-32 hours.

[0071] In the present application, the particle size of the raw material particles is preferably 20-120 microns, more preferably 40-100 microns, and more preferably 60-80 microns.

[0072] The present application finally deposits the raw material particles obtained in the above step on a substrate after air plasma spraying, to obtain a wave-absorbing ceramic coating.

[0073] In the present application, the temperature of the air plasma spraying is preferably greater than or equal to 8000°C, more preferably greater than or equal to 8100°C, and more preferably greater than or equal to 8200°C.

[0074] In the present application, the power of the air plasma spraying is preferably 35-40 kw, more preferably 36-39 kw, and preferably 37-38 kw.

[0075] In the present application, the spraying distance of the air plasma spraying is preferably 80-120 mm, more preferably 88-112 mm, and more preferably 96-108 mm.

[0076] In the present application, the powder feeding amount of the air plasma spraying is preferably 10-20 g / min, more preferably 12-18 g / min, and more preferably 14-16 g / min.

[0077] In the present application, the plasma gas of the air plasma spraying preferably includes argon and hydrogen.

[0078] In the present application, the flow rate of the carrier gas of the air plasma spraying is preferably 2.5-3.0 SLPM, more preferably 2.6-2.9 SLPM, and more preferably 2.7-2.8 SLPM.

[0079] In the present application, after solid phase sintering, lanthanum oxide and ferric oxide form a composite ferrite ceramic material including lanthanum ferrite, ferric oxide, and one or more of ferric oxide, ferrous oxide, iron, and non-stoichiometric compounds. Further, after atmospheric plasma spraying, the components in the composite ferrite ceramic material further undergo chemical changes to form a complex composition of the composite ceramic coating.

[0080] The present application is a complete and detailed overall technical solution, which better ensures the specific composition and structure of the composite ceramic material and the wave-absorbing ceramic coating, and further improves the wave-absorbing performance and high-temperature resistance of the wave-absorbing ceramic coating. The above-mentioned composite ferrite ceramic material, the heat-spraying wave-absorbing ceramic coating and the preparation method thereof can specifically include the following steps:

[0081] In the process of synthesizing the thermal barrier ceramic material, an excess of Fe2O3 is used to introduce the magnetic element Fe, and then solid phase synthesis and plasma spraying are performed to obtain a composite ceramic coating with wave-absorbing performance and high-temperature resistance.

[0082] The specific technical solution is as follows:

[0083] 0.5 parts of La2O3 and 6-8 parts of Fe2O3 are weighed as synthesis raw materials, and after being mixed uniformly, high-temperature solid phase reaction is performed under N2 atmosphere, the synthesis temperature is 1351-1450℃, and the reaction time is 3-6 hours, so that the wave-absorbing ceramic material with ferrite as the main component can be obtained, but still contains unreacted Fe2O3.

[0084] 0.8% ammonium citrate and 2% gum arabic are added to the synthesized ferrite ceramic material, ball-milled in a deionized water medium for 24 hours, and then spray granulated into 20-120 micron particles to improve the flowability of the powder material and thus improve the efficiency of plasma spraying.

[0085] After granulation, the ferrite ceramic particles are deposited on a graphite substrate after atmospheric plasma spraying. XRD analysis shows that the main components of the ceramic coating include ferrite hard magnetic material and unreacted Fe2O3 and other ferric oxides, and the ceramic coating does not undergo oxidation or decomposition of ferrite, and has a similar composition to the ceramic material, but due to the rapid cooling and deposition of the ceramic material on the substrate during thermal spraying, the crystallinity of the ceramic material is greatly reduced.

[0086] Due to the strong magnetism of the ferrite hard magnetic material, the magnetic loss of the electromagnetic wave is large, and the structure of the ferrite hard magnetic material can still maintain its stability after thermal spraying and well inherit its wave-absorbing performance, so the ferrite hard magnetic material can be used as a wave-absorbing agent in the thermal barrier ceramic coating. Traditional wave-absorbing materials will decompose during thermal spraying and no longer have wave-absorbing function, so they can only be prepared by brushing or pasting, and cannot be directly applied to the thermal barrier ceramic coating.

[0087] The above content of the present application provides a composite ferrite ceramic material, a heat-spraying wave-absorbing ceramic coating and a preparation method thereof. The composite ferrite ceramic material with specific composition and proportion is specially designed in the present application, and then the composite ceramic coating is obtained. Moreover, the present application greatly increases the amount of Fe2O3, thereby improving the overall performance of the composite ferrite ceramic material. The present application also changes the conventional usage of the atmospheric plasma spraying process which does not occur chemical reaction, and introduces the hard magnetic material by using specific chemical reaction process, thereby improving the magnetic loss of the electromagnetic wave of the wave-absorbing coating. Moreover, the composition of the coating is a composite ceramic which has certain high-temperature resistance, and the composite ceramic coating with high-temperature resistance and wave-absorbing function is obtained. The high-temperature solid-phase synthesis is carried out under the condition of air isolation, and the ceramic material with complex and multiple components can be synthesized. After the spray granulation and the atmospheric plasma spraying, the structural stability of the ceramic material can still be maintained, and the wave-absorbing performance is well inherited. The difficulty that the traditional wave-absorbing material cannot be heat-sprayed is solved. Therefore, the composite ferrite ceramic material provided by the present application can be applied to the thermal barrier ceramic coating as a wave-absorbing agent, and contributes to the national defense and military industry.

[0088] In the process of synthesizing the thermal barrier ceramic material, the present application adds excessive Fe2O3 raw material to introduce the magnetic element Fe, and then carries out the solid-phase synthesis. The composite ceramic coating with wave-absorbing performance and high-temperature resistance is prepared by the special combination of plasma spraying. The composite ceramic material with specific composition and proportion provided by the present application obtains ceramic particles after granulation. After the atmospheric plasma spraying, the coating is deposited on the substrate. The main component of the coating is changed by the chemical reaction of LaFeO3. Moreover, the high temperature and oxygen-deficient environment in the process of atmospheric plasma spraying can further promote the reaction. In the present application, the main component of the coating material is changed after the APS process. The high content of Fe2O3 in the batching material is beneficial to improve the synthesis efficiency of the ceramic material. After the atmospheric plasma spraying, the concentration of the wave-absorbing material is greatly improved, and the good wave-absorbing performance is exhibited.

[0089] The production process of the thermal barrier ceramic coating provided by the present application, i.e. the solid-phase synthesis method and the plasma spraying method, directly prepares the composite ceramic coating with wave-absorbing function. The main wave-absorbing component is the ferrite hard magnetic material, and the magnetic property and the wave-absorbing performance are both high. The present application solves the shackles of the conventional ferrite which cannot use the plasma spraying process. The high temperature in the spraying process is avoided, which can cause the decomposition of the conventional ferrite and cause the disappearance of the magnetic property and the wave-absorbing performance. Moreover, the plasma spraying process is the key process for the formation of the wave-absorbing agent in the present application.

[0090] In order to further illustrate the present application, the composite ferrite ceramic material, the wave-absorbing ceramic coating and the preparation method thereof provided by the present application are described in detail below in combination with examples. It should be understood that these examples are implemented on the premise of the technical scheme of the present application, and detailed implementation manners and specific operation processes are given, which are only for further illustrating the features and advantages of the present application, but not for limiting the present application, and the protection scope of the present application is not limited to the following examples.

[0091] Example 1

[0092] The two raw materials, 0.5 parts of La2O3 and 6 parts of Fe2O3, are mixed in anhydrous ethanol medium for 10 hours, and after drying and alcohol removal, the wave-absorbing ceramic material can be obtained by solid-phase sintering at 1355℃ for 3 hours in a N2 atmosphere.

[0093] 0.8% ammonium citrate and 2% gum arabic are added to the ceramic material, and ball milling is performed in deionized water medium for 24 hours, and then spray granulation is performed to obtain 80 micron particles. The atmospheric plasma spraying process is adopted, argon and hydrogen are used as process gas, the carrier gas flow is 2.7 SLPM, the powder feeding amount is 15 g / min, and the spraying distance is 100 mm. The granulated ceramic particles are sprayed layer by layer on the graphite substrate to obtain ceramic coatings with different thicknesses of wave-absorbing function.

[0094] The composite ceramic material and the composite ceramic coating prepared in Example 1 of the present application are characterized.

[0095] Referring to Figure 1 , Figure 1 The XRD pattern of the composite ceramic material and the composite ceramic coating prepared in Example 1 of the present application is shown in FIG. 1.

[0096] From Figure 1 It can be seen that the ceramic coating still contains unreacted Fe2O3.

[0097] The composite ceramic material and the composite ceramic coating prepared in Example 1 of the present application are detected.

[0098] Referring to Figure 2 , Figure 2 The electromagnetic wave reflection loss diagram of the composite ceramic material prepared in Example 1 of the present application is shown in FIG. 2.

[0099] Referring to Figure 3 , Figure 3 The electromagnetic wave reflection loss diagram of the composite ceramic coating prepared in Example 1 of the present application is shown in FIG. 3.

[0100] The reflection loss performance of the wave-absorbing material is evaluated, mainly focusing on two indexes, the reflection loss and the effective absorption bandwidth. It is generally considered that the wave-absorbing material has good wave-absorbing performance when the reflection loss is less than -10 dB, and the effective absorption bandwidth refers to the response frequency range in which the reflection loss is less than -10 dB, Figure 2 The effective absorption bandwidth in the ceramic coating is relatively narrow, and the effective absorption bandwidth in the ceramic coating is relatively narrow, Figure 3 The effective absorption bandwidth of the ceramic coating is relatively narrow, and the effective absorption bandwidth of the ceramic coating is relatively narrow,

[0101] Referring to Figure 4 Figure 4 The hysteresis loop diagram of the prepared composite ceramic material and the composite ceramic coating in Example 1 of the present application.

[0102] From Figure 4 It can be seen that the magnetic saturation intensity of the ceramic coating is obviously improved before and after spraying, which can reach nearly 50emu / g, which is obviously higher than the intensity of the ceramic material before spraying, and the magnetic performance of the coating after spraying is greatly improved. It can be seen that the increase of the content of Fe2O3 in the ingredients is not only beneficial to improve the synthesis efficiency of the ceramic material, but also can greatly improve the concentration of the wave-absorbing material after atmospheric plasma spraying and exhibit good wave-absorbing performance.

[0103] The composite ferrite ceramic material, the heat-spraying wave-absorbing ceramic coating and the preparation method thereof provided by the present application are introduced in detail above, and the principles and implementation modes of the present application are described by applying specific examples in this paper. The above description of the examples is only used to help understand the method and core idea of the present application, including the best mode, and also enables any person skilled in the art to practice the present application, including manufacturing and using any device or system, and implementing any combined method. It should be pointed out that, for those skilled in the art, some improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application. The scope of protection of the present application is defined by the claims, and can include other embodiments that can be thought of by those skilled in the art. If these other embodiments have structural elements that are not different from the literal expression of the claims, or if they include equivalent structural elements that are not substantially different from the literal expression of the claims, then these other embodiments should also be included in the scope of the claims.​

Claims

1. A composite ferrite ceramic material, characterized by, The composite ferrite ceramic material is obtained by solid phase sintering of lanthanum oxide and ferric oxide; The mass ratio of the lanthanum oxide to the ferric oxide is 0.5:(6-8).

2. The composite ferrite ceramic material of claim 1, wherein, The temperature of the solid phase sintering is 1351-1450℃; The time of the solid phase sintering is 3-6 hours.

3. The composite ferrite ceramic material of claim 1, wherein, The solid phase sintering is specifically solid phase sintering under a protective atmosphere. The composite ferrite ceramic material contains ferric oxide.

4. A wave-absorbing ceramic coating, characterized by, According to the mass fraction of raw materials, the composite ferrite ceramic material comprises: Composite ferrite ceramic material 95-98 parts by weight; Granulating agent 0.5-1 parts by weight; Binder 1-3 parts by weight; Solvent; The composite ferrite ceramic material comprises the composite ceramic material according to any one of claims 1-3.

5. The wave-absorbing ceramic coating according to claim 4, characterized in that, The granulating agent comprises ammonium citrate; The binder comprises one or more of gum arabic, PVA, PEO, PEG, cellulose and EVA; The solvent comprises water.

6. A method for producing a wave-absorbing ceramic coating according to any one of claims 4 to 5, characterized in that The method comprises the following steps: 1) After mixing the composite ferrite ceramic material, the granulating agent, the binder and the solvent, raw material particles are obtained by spray granulation; 2) After the raw material particles obtained in the above step are deposited on a substrate by atmospheric plasma spraying, a wave-absorbing ceramic coating is obtained.

7. The production method according to claim 6, wherein The mixing mode comprises ball milling; The mixing time is 20-40 hours; The particle size of the raw material particles is 20-120 microns.

8. The preparation method according to claim 6, characterized in that, The temperature of the atmospheric plasma spraying is greater than or equal to 8000℃; The power of the atmospheric plasma spraying is 35-40kw.

9. The preparation method according to claim 6, characterized in that, The spraying distance of the atmospheric plasma spraying is 80-120mm; The powder feeding amount of the atmospheric plasma spraying is 10-20g / min.

10. The method of claim 6, wherein, The plasma gas of the atmospheric plasma spraying comprises argon and hydrogen; The flow rate of the carrier gas of the atmospheric plasma spraying is 2.5-3.0SLPM.

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