High-entropy ceramic powder and preparation method thereof, and thermal regulation coating and preparation method and application thereof

Abstract

According to the preparation method of the high-entropy ceramic powder, the preparation process is simple, and high-entropy ceramic is high in stability at high temperature. The invention also provides a preparation method of the thermal regulation coating by adopting the high-entropy ceramic powder, and the prepared thermal regulation coating is simple in preparation process, does not depend on special equipment, is low in cost and good in performance, can be coated in a microcrystalline glass tube and is suitable for the fields of injection molds and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of coatings, and in particular relates to a high-entropy ceramic powder and a preparation method thereof, a heat-regulating coating and a preparation method thereof, and an application. Background Art

[0002] Ceramic materials have unique physical and chemical properties. Infrared radiation technology is inseparable from the basis of ceramic materials. A new type of ceramic material combined with infrared technology is named infrared radiation ceramic, which refers to an inorganic functional material with a high emissivity or special emission performance in the infrared band. The application of infrared radiation ceramics is not limited to heating furnaces in industries such as smelting and petroleum separation, and has also received extensive attention in civil and military fields. Currently, the application fields of infrared radiation ceramic materials include: heat dissipation of spacecraft, infrared heating, building coatings, antibacterial medical care, etc.

[0003] The infrared emissivity value is the criterion for judging the infrared radiation performance of materials. In the prior art, the ways to improve the infrared emissivity of ceramic materials mainly include: chemical doping substitution, material component compounding, controlling crystal morphology, etc. Among them, chemical doping substitution can significantly improve the radiation performance of materials in the near-infrared wave region. First, in the near-infrared wave region, the absorption mechanism of materials is mainly based on free carriers, which belongs to the transition within the energy band. After introducing impurities into the system, there are differences in the radii of impurity ions and the replaced elements, and the periodicity of the original lattice is destroyed. The electronic energy states in the impurity substitution region change, and impurity energy levels are formed at the electron band gap, reducing the minimum energy value required for free carrier transition, enhancing the absorption of free carriers, and increasing the infrared radiation rate. Second, chemical doping substitution destroys the symmetry of the material lattice, the lattice is distorted, the vibration activity of the crystal structure is enhanced, promoting the vibration absorption of the lattice, and doping relatively increases the inherent vibration frequency, increasing the radiation rate of the material in the mid-infrared wave region. Finally, if there is a charge imbalance phenomenon after chemical doping substitution, it will lead to small-scale fluctuations centered on defects, changing the vibration and rotation states of molecules, and promoting the intrinsic absorption coefficient of the material. However, traditional chemical doping substitution is limited by the "solid solubility limit", so the adjustable range is very limited. Summary of the Invention

[0004] In order to solve at least one technical problem in the prior art, a high-entropy ceramic powder and a preparation method thereof, a heat-regulating coating and a preparation method thereof, and an application are provided. The high-entropy ceramic has a high infrared emissivity and the heat-regulating coating has excellent performance. To achieve the above technical objectives, the technical solutions adopted in the embodiments of the present invention are as follows: In the first aspect, an embodiment of the present invention provides a preparation method of a high-entropy ceramic powder, including the following steps: Step S11, preparing the first mixed solution: By mass, add 1 to 50 parts of manganese carbonate and 1 to 50 parts of strontium carbonate to water. After stirring evenly, add 30 to 40 parts of the first inorganic acid and dissolve until there is no precipitate, thereby obtaining the first mixed solution; Step S12, preparing the second mixed solution: Add 100 to 500 parts of lanthanum nitrate, 1 to 40 parts of copper nitrate, 5 to 200 parts of iron nitrate, and 1 to 100 parts of cobalt nitrate to the first mixed solution obtained in step S11, thereby obtaining the second mixed solution; Step S13, preparing the synthesis solution, which includes: Add 1 to 200 parts of tetrabutyl titanate to the second mixed solution obtained in step S12. After heating to 55 to 65 °C, add the second inorganic acid and stir for 1 to 3 h; Then adjust the pH value to 4 to 8; and keep warm for 1 to 3 h; After that, keep warm at a temperature of 50 to 90 °C for 10 to 15 h to obtain the synthesis solution; Step S14, evaporating to dryness and burning, which includes: Evaporate the synthesis solution to dryness with stirring at a temperature of 95 to 105 °C in step S13 to obtain a gel-like material; Ignite the gel-like material to obtain a black material; Step S15, calcining: Calcine the black material obtained in step S14 at a temperature of 600 to 1000 °C for 1 to 3 h to obtain the high-entropy ceramic powder.

[0005] Further, in step S11, preparing the first mixed solution includes: By mass, add 2 to 30 parts of manganese carbonate and 5 to 40 parts of strontium carbonate to water. After stirring evenly, add 30 to 40 parts of the first inorganic acid and dissolve until there is no precipitate, thereby obtaining the first mixed solution; And / or, in step S12, preparing the second mixed solution includes: Add 200 to 300 parts of lanthanum nitrate, 2 to 25 parts of copper nitrate, 20 to 100 parts of iron nitrate, and 5 to 50 parts of cobalt nitrate to the first mixed solution obtained in step S11, thereby obtaining the second mixed solution; And / or, in step S13: The step of "adding 1 to 200 parts of tetrabutyl titanate to the second mixed solution obtained in step S12, heating to 55 to 65 °C, adding the second inorganic acid, and stirring for 1 to 3 h" includes: Add 10 to 110 parts of tetrabutyl titanate to the second mixed solution obtained in step S12. After heating to 55 to 65 °C, add the second inorganic acid and stir for 1 to 3 h; And / or, the "pH value is adjusted to 4 - 8 again; and keep warm for 1 - 3 h" includes: The pH value is adjusted to 4 - 8 again; and keep warm for 1 - 3 h; And / or, the "then keep warm at a temperature of 50 - 90 °C for 10 - 15 h to obtain the synthetic solution" includes: Then keep warm at a temperature of 75 - 85 °C for 10 - 15 h to obtain the synthetic solution; And / or, in the step S14: The "evaporate the synthetic solution with stirring at a temperature of 95 - 105 °C in step S13 to obtain a gel-like material" includes: Evaporate the synthetic solution with stirring at a temperature of 95 - 105 °C in step S13 to obtain a gel-like material; Ignite the gel-like material to obtain a black material; And / or, in step S15, calcination: calcine the black material obtained in step S14 at a temperature of 600 - 1000 °C for 1 - 3 h to obtain the high-entropy ceramic powder.

[0006] Further, in step S11, the first inorganic acid includes nitric acid; And / or, in step S13, the second inorganic acid includes citric acid; And / or, in step S13, the pH value is adjusted to 4 - 8 by concentrated ammonia water.

[0007] In the second aspect, the present invention provides the high-entropy ceramic powder prepared by the preparation method of the above high-entropy ceramic powder.

[0008] In the third aspect, an embodiment of the present invention provides a composition of a heat-regulating coating. The heat-regulating coating includes water and a slurry matrix. It is characterized in that, by weight, the slurry matrix includes: 5 - 50 parts of the above high-entropy ceramic powder; The slurry matrix further includes: 5 - 20 parts of phosphate solution, 5 - 20 parts of inorganic sol, 2 - 10 parts of glass powder, 2 - 10 parts of aluminum nitride powder, 2 - 10 parts of tetrabutyl titanate, 2 - 10 parts of high-temperature antioxidant, 2 - 10 parts of dispersant, 2 - 10 parts of film-forming agent, 2 - 10 parts of leveling agent, 2 - 10 parts of anti-settling agent, 2 - 10 parts of defoaming agent, 2 - 10 parts of thickening agent.

[0009] Further, the heat-regulating coating includes water and a slurry matrix; By weight, the slurry matrix includes: 15 - 25 parts of the above high-entropy ceramic powder; The slurry matrix further includes: 7 - 10 parts of a phosphate solution (40 - 50 wt%), 8 - 12 parts of an inorganic sol, 4 - 6 parts of glass powder, 4 - 6 parts of aluminum nitride powder, 4 - 6 parts of tetrabutyl titanate, 4 - 6 parts of a high - temperature oxidation inhibitor, 4 - 6 parts of a dispersant, 4 - 6 parts of a film - forming agent, 4 - 6 parts of a leveling agent, 4 - 6 parts of an anti - settling agent, 4 - 6 parts of an antifoaming agent, and 4 - 6 parts of a thickening agent.

[0010] Further, the inorganic sol includes an aluminum - based sol; and / or, the solute of the phosphate solution includes aluminum dihydrogen phosphate and aluminum chromium phosphate; and / or, the glass powder is selected from one or more of silicate, borate, silicon - boron, and phosphate glass; and / or, the high - temperature oxidation inhibitor is selected from one or more of phosphoric acid, zinc phosphate, ammonium phosphate tribasic, and boric acid; wherein, the pH value of the aluminum - based sol is 5 - 7 and / or the particle size of the colloidal particles of the aluminum - based sol is 20 - 80 nm.

[0011] Fourthly, the present invention provides a preparation method of a thermal - regulating coating, including the following steps: Step S21, preparing a first mixed slurry. At 40 - 80 °C, uniformly mix the aluminum - based sol, phosphate solution, high - temperature oxidation inhibitor, and water in the composition of the above - mentioned thermal - regulating coating to obtain the first mixed slurry; Step S22, preparing a second mixed slurry. Add the glass powder, high - entropy ceramic powder, and aluminum nitride powder in the composition of the above - mentioned thermal - regulating coating into the first mixed slurry obtained in Step S21, and disperse for 0.5 - 1 h to obtain the second mixed slurry; Step S23, preparing a third mixed slurry. This step includes: Add the tetrabutyl titanate in the composition of the above - mentioned thermal - regulating coating into the second mixed slurry obtained in Step S22, and perform the first stirring at a temperature of 40 - 80 °C, and then cool; After cooling, add the dispersant, film - forming agent, leveling agent, anti - settling agent, antifoaming agent, and thickening agent in the composition of the above - mentioned thermal - regulating coating, and perform the second stirring at room temperature to obtain the third mixed slurry; Step S24, rolling: Roll the third mixed slurry obtained in Step S23 to obtain the thermal - regulating coating.

[0012] Fifthly, the present invention provides a thermal - regulating coating prepared by the above - mentioned preparation method of the thermal - regulating coating.

[0013] Sixthly, the present invention provides the application of the above - mentioned thermal - regulating coating in an injection mold.

[0014] The beneficial effects brought by the technical solution provided by the embodiment of the present invention are as follows: In the embodiment of the present invention, the preparation process of the high-entropy ceramic is simple, the reaction system is stable, and high-entropy ceramic powder with the structural formula of (La 0.8 Sr 0.2 )(Mn x Ti y Cu z Co m Fe 1-x-y-z-m )O3 can be obtained. The preparation process of the thermal regulation coating is simple, does not rely on special equipment, has low cost, and has good performance. It can be coated on the microcrystalline glass tube and is applicable to fields such as injection molds. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is the XRD pattern of the high-entropy ceramic in Embodiment 1 of the present invention and related embodiments.

[0016] Figure 2 It is the XRD pattern of the high-entropy ceramic in Embodiment 1 of the present invention and related embodiments.

[0017] Figure 3 It is the XRD pattern of the high-entropy ceramic in Embodiment 1 of the present invention and related embodiments. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0019] In addition, it should be understood that after reading the content disclosed in the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the protection scope defined by the present invention.

[0020] First, an embodiment of the present invention provides a method for preparing high-entropy ceramic powder, including the following steps: Step S11, preparing a first mixed solution: By mass, add 1 to 50 parts of manganese carbonate and 1 to 50 parts of strontium carbonate to water, stir evenly, and then add 30 to 40 parts of a first inorganic acid to dissolve until there is no precipitate, thereby obtaining the first mixed solution; Step S12, preparing a second mixed solution: Add 100 to 500 parts of lanthanum nitrate, 1 to 40 parts of copper nitrate, 5 to 200 parts of iron nitrate, and 1 to 100 parts of cobalt nitrate to the first mixed solution obtained in step S11 to obtain the second mixed solution; Step S13, preparing a synthesis solution, which includes: Add 1 to 200 parts of tetrabutyl titanate to the second mixed solution obtained in step S12, heat up to 55 to 65 °C, then add a second inorganic acid and stir for 1 to 3 hours; Then adjust the pH value to 4 to 8; and keep warm for 1 to 3 hours; After that, keep warm at a temperature of 50 to 90 °C for 10 to 15 hours to obtain the synthesis solution; Step S14, evaporate to dryness and burn, this step includes: Evaporate the synthesis solution obtained in step S13 to dryness with stirring at a temperature of 95 to 105 °C to obtain a gel-like material; Ignite the gel-like material to obtain a black material; Step S15, calcine: Calcinate the black material obtained in step S14 at a temperature of 600 to 1000 °C for 1 to 3 hours to obtain the high-entropy ceramic powder.

[0021] Furthermore, the preparation method of the high-entropy ceramic powder includes the following steps: In step S11, the preparation of the first mixed solution includes: By mass, add 2 to 30 parts of manganese carbonate and 5 to 40 parts of strontium carbonate to water, stir evenly, and then add 30 to 40 parts of a first inorganic acid to dissolve until there is no precipitate to obtain the first mixed solution; And / or, in step S12, the preparation of the second mixed solution includes: Add 200 to 300 parts of lanthanum nitrate, 2 to 25 parts of copper nitrate, 20 to 100 parts of iron nitrate, and 5 to 50 parts of cobalt nitrate to the first mixed solution obtained in step S11 to obtain the second mixed solution; And / or, in step S13: The "add 1 to 200 parts of tetrabutyl titanate to the second mixed solution obtained in step S12, heat up to 55 to 65 °C, then add a second inorganic acid and stir for 1 to 3 hours" includes: Add 10 to 110 parts of tetrabutyl titanate to the second mixed solution obtained in step S12, heat up to 55 to 65 °C, then add a second inorganic acid and stir for 1 to 3 hours; And / or, the "then adjust the pH value to 4 to 8; and keep warm for 1 to 3 hours" includes: Then adjust the pH value to 4 to 8; and keep warm for 1 to 3 hours; And / or, the "after that, keep warm at a temperature of 50 to 90 °C for 10 to 15 hours to obtain the synthesis solution" includes: After that, keep warm at a temperature of 75 to 85 °C for 10 to 15 hours to obtain the synthesis solution; And / or, in step S14: The "step of evaporating the synthesis solution to dryness with stirring at a temperature of 95 to 105 °C in step S13 to obtain a gel-like material" includes: Evaporating the synthesis solution to dryness with stirring at a temperature of 95 to 105 °C in step S13 to obtain a gel-like material; Igniting the gel-like material to obtain a black material; And / or, step S15, calcination: calcining the black material obtained in step S14 at a temperature of 600 to 1000 °C for 1 to 3 h to obtain the high-entropy ceramic powder.

[0022] The first inorganic acid and the second inorganic acid can increase the solubility of the reactants. In the present application, the types of the first inorganic acid and the second inorganic acid are not limited. For example, they can be nitric acid, carbonic acid, hydrochloric acid, sulfuric acid, etc. When adjusting the pH, concentrated ammonia water, sodium hydroxide, etc. can be added.

[0023] Further, in step S11, the first inorganic acid includes nitric acid; And / or, in step S13, the second inorganic acid includes citric acid; And / or, in step S13, the pH value is adjusted to 4 to 8 by concentrated ammonia water.

[0024] It should be noted that in step S13, the citric acid and the concentrated ammonia water are used to adjust the pH value. 75 to 85 °C is the optimal temperature range for synthesizing the high-entropy ceramic. Keep it warm at this temperature for 10 to 15 h to ensure the completion of the synthesis of the high-entropy ceramic.

[0025] In a second aspect, the present invention provides a high-entropy ceramic powder prepared by the preparation method of the above high-entropy ceramic powder.

[0026] Furthermore, the structural formula of the high-entropy ceramic powder is (La 0.8 Sr 0.2 )(Mn x Ti y Cu z Co m Fe 1-x-y-z-m )O3.

[0027] In a third aspect, an embodiment of the present invention provides a composition of a heat-regulating coating. The heat-regulating coating includes water and a slurry matrix. It is characterized in that, by weight, the slurry matrix includes: 5 to 50 parts of the high-entropy ceramic powder as described in claim 4; The slurry matrix further includes: 5 - 20 parts of phosphate solution, 5 - 20 parts of inorganic sol, 2 - 10 parts of glass powder, 2 - 10 parts of aluminum nitride powder, 2 - 10 parts of tetrabutyl titanate, 2 - 10 parts of high-temperature antioxidant, 2 - 10 parts of dispersant, 2 - 10 parts of film-forming agent, 2 - 10 parts of leveling agent, 2 - 10 parts of anti-settling agent, 2 - 10 parts of defoaming agent, 2 - 10 parts of thickening agent.

[0028] Further, the thermal regulation coating comprises water and a slurry matrix; By weight, the slurry matrix comprises: 15 - 25 parts of the above-mentioned high-entropy ceramic powder; The slurry matrix further comprises: 7 - 10 parts of phosphate solution with 40 - 50wt%, 8 - 12 parts of inorganic sol, 4 - 6 parts of glass powder, 4 - 6 parts of aluminum nitride powder, 4 - 6 parts of tetrabutyl titanate, 4 - 6 parts of high-temperature antioxidant, 4 - 6 parts of dispersant, 4 - 6 parts of film-forming agent, 4 - 6 parts of leveling agent, 4 - 6 parts of anti-settling agent, 4 - 6 parts of defoaming agent, 4 - 6 parts of thickening agent.

[0029] Further, the inorganic sol comprises an aluminum-based sol; And / or, the solute of the phosphate solution comprises aluminum dihydrogen phosphate and aluminum chromium phosphate; And / or, the glass powder is selected from one or more of silicate, borate, silicon boron, and phosphate glass; And / or, the high-temperature antioxidant is selected from one or more of phosphoric acid, zinc phosphate, ammonium phosphate tribasic, and boric acid; Wherein, the pH value of the aluminum-based sol is 5 - 7 and / or the particle size of the colloidal particles of the aluminum-based sol is 20 - 80nm.

[0030] It should be noted that in this application, the phosphate solution is mainly used for bonding and can resist high temperature; the aluminum-based sol can improve the film-forming property of the thermal regulation coating, and together with the phosphate solution, they promote each other to improve the film-forming effect of the thermal regulation coating; the tetrabutyl titanate is a coupling agent, which can make the combination between phosphates closer; the glass powder can ensure that the thermal regulation coating plays a role in sealing holes and protecting at high temperature, and improves the stability of the thermal regulation coating in a high-temperature environment; the high-temperature antioxidant can prevent the thermal regulation coating from oxidizing.

[0031] The phosphate solution in this application may contain a curing agent, and the curing agent includes oxides and / or hydroxides of magnesium, copper, zinc, zirconium, and / or aluminum. The content of the curing agent is 2 - 10wt% of the solute of the phosphate solution, and the curing agent can improve the temperature resistance and bonding property of the thermal regulation coating.

[0032] Fourth aspect, the present invention provides a method for preparing a heat-regulating coating, comprising the following steps: Step S21, preparing a first mixed slurry. At a temperature of 40 - 80°C, uniformly mix the aluminum-based sol, phosphate solution, high-temperature oxidation inhibitor, and water in the composition of the above heat-regulating coating to obtain the first mixed slurry; Step S22, preparing a second mixed slurry. Add the glass powder, high-entropy ceramic powder, and aluminum nitride powder in the composition of the above heat-regulating coating to the first mixed slurry obtained in Step S21, and disperse for 0.5 - 1 h to obtain the second mixed slurry; Step S23, preparing a third mixed slurry, which includes: Add tetrabutyl titanate in the composition of the above heat-regulating coating to the second mixed slurry obtained in Step S22, and perform the first stirring at a temperature of 40 - 80°C, and then cool down; After cooling, add the dispersant, film-forming agent, leveling agent, anti-settling agent, defoaming agent, and thickening agent in the composition of the above heat-regulating coating, and perform the second stirring at room temperature to obtain the third mixed slurry; Step S24, rolling: Roll the third mixed slurry obtained in Step S23 to obtain the heat-regulating coating.

[0033] It should be noted that the stirring speed and stirring time of the first stirring are not limited, and the stirring speed and stirring time of the second stirring are also not limited, and both can be adaptively adjusted according to actual needs.

[0034] Furthermore, in Step S23, the stirring speed of the first stirring is 500 - 2000 r / min and / or the stirring time is 1 - 4 h; And / or, in Step S23, the stirring speed of the second stirring is 500 - 2000 r / min and / or the stirring time is 1 - 4 h; It can be understood that in Step S21, those skilled in the art can add an appropriate amount of water to form a slurry according to actual needs. In Step S24, when rolling the third mixed slurry, any rolling equipment, such as a three-roll press, can be used for rolling, and it can be rolled to any required thickness.

[0035] Furthermore, when using a rolling press to roll, the preset thickness is less than or equal to 10 μm.

[0036] Fifth aspect, the present invention provides a heat-regulating coating obtained by the preparation method of the above heat-regulating coating.

[0037] Sixth aspect, the present invention provides the application of the above heat-regulating coating in an injection mold.

[0038] It should be noted that during the injection molding process of plastic products, the mold temperature is crucial for the quality of plastic products. Further, the present invention provides the application of the above-mentioned thermal regulation coating in a variable-temperature injection mold. The thermal regulation coating described in this application can be used to coat on a glass-ceramic tube, and the glass-ceramic tube is arranged in the temperature control system of the injection mold. Since the thermal regulation coating has infrared radiation characteristics, it can achieve rapid heating and can also conduct heat away through additional thermal radiation to achieve cooling.

[0039] In the following specific examples, operations not specified in terms of conditions are carried out under conventional conditions or conditions recommended by the manufacturer. All raw materials not specified in terms of the manufacturer and specifications are conventional products that can be obtained through commercial purchase.

[0040] Example 1 A preparation method of high-entropy ceramic powder, comprising the following steps: Step S11, preparing a first mixed solution: By mass, add 5 parts of manganese carbonate and 10 parts of strontium carbonate to 200 parts of water. After stirring evenly, add 35 parts of nitric acid and dissolve until there is no precipitate to obtain the first mixed solution; Step S12, preparing a second mixed solution: Add 210 parts of lanthanum nitrate, 5 parts of copper nitrate, 22 parts of iron nitrate, and 8 parts of cobalt nitrate to the first mixed solution obtained in step S11, and then add 2200 parts of water for dilution to obtain the second mixed solution; Step S13, preparing a synthesis solution, which includes: Add 18 parts of tetrabutyl titanate to the second mixed solution obtained in step S12. After heating to 60 °C, add citric acid and stir for 2 h; Then add concentrated ammonia water to adjust the pH value to 6; and keep warm for 2 h; After that, keep warm at 80 °C for 10 h to obtain the synthesis solution; Step S14, evaporating to dryness and burning, which includes: Evaporate the synthesis solution obtained in step S13 to dryness with stirring at 100 °C to obtain a gel-like material; Ignite the gel-like material to obtain a black material; Step S15, calcining: Calcine the black material obtained in step S14 at 800 °C for 2 h to obtain the high-entropy ceramic powder.

[0041] Related examples Keeping other conditions of Example 1 unchanged, only changing the pH value in the range of 4 - 6 in step S13 and the calcination temperature in the range of 600 - 1000 in step S15, high-entropy ceramic powders conforming to the structural formula (La 0.8 Sr0.2 )(Mn 0.2 Ti 0.2 Cu 0.2 Co 0.2 Fe 0.2 )O3 of the high-entropy ceramic powder.

[0042] Example 2 A method for preparing a high-entropy ceramic powder, comprising the following steps: Step S11, preparing a first mixed solution: By mass, 25 parts of manganese carbonate and 31 parts of strontium carbonate are added to 100 parts of water. After stirring evenly, 30 parts of nitric acid are added and dissolved until there is no precipitate, obtaining the first mixed solution; Step S12, preparing a second mixed solution: 270 parts of lanthanum nitrate, 20 parts of copper nitrate, 50 parts of iron nitrate, and 40 parts of cobalt nitrate are added to the first mixed solution obtained in Step S11, and then diluted with 1000 parts of water to obtain the second mixed solution; Step S13, preparing a synthesis solution, which includes: 105 parts of tetrabutyl titanate are added to the second mixed solution obtained in Step S12. After heating to 55 °C, a second acid is added and stirred for 3 h; Then the pH value is adjusted to 6; and it is kept warm for 1 h; After that, it is kept warm at 80 °C for 10 h to obtain the synthesis solution; Step S14, evaporating to dryness and burning, which includes: The synthesis solution is evaporated to dryness with stirring at 95 °C in Step S13 to obtain a gel-like material; The gel-like material is ignited to obtain a black material; Step S15, calcining: The black material obtained in Step S14 is calcined at 800 °C for 3 h to obtain the high-entropy ceramic powder.

[0043] Example 3 A method for preparing a high-entropy ceramic powder, comprising the following steps: Step S11, preparing a first mixed solution: By mass, 13 parts of manganese carbonate and 30 parts of strontium carbonate are added to 500 parts of water. After stirring evenly, 40 parts of nitric acid are added and dissolved until there is no precipitate, obtaining the first mixed solution; Step S12, preparing a second mixed solution: 265 parts of lanthanum nitrate, 20 parts of copper nitrate, 100 parts of iron nitrate, and 45 parts of cobalt nitrate are added to the first mixed solution obtained in Step S11, and then diluted with 3000 parts of water to obtain the second mixed solution; Step S13, preparing a synthesis solution, which includes: Add 75 parts of tetrabutyl titanate to the second mixed solution prepared in step S12, heat up to 65 °C, then add the second acid and stir for 1 h; Then add concentrated ammonia water to adjust the pH value to 6; and keep warm for 3 h; After that, keep warm at 80 °C for 10 h to obtain the synthetic solution; Step S14, evaporate to dryness and burn, this step includes: Evaporate the synthetic solution to dryness with stirring at 105 °C in step S13 to obtain a gel-like material; Ignite the gel-like material to obtain a black material; Step S15, calcine: Calcinate the black material obtained in step S14 at 800 °C for 1 h to obtain the high-entropy ceramic powder.

[0044] Taking the above Example 1 as an example, the preferred embodiments of the present invention will be further described.

[0045] Example 4 A composition of a thermal regulation coating, including water and a slurry matrix. By weight, the slurry matrix includes: 20 parts of the high-entropy ceramic powder in Example 1; The slurry matrix further includes: 8 parts of a phosphate solution of 40 - 50 wt%, 10 parts of an aluminum-based sol, 5 parts of a silicate glass powder, 5 parts of aluminum nitride powder, 5 parts of tetrabutyl titanate, 5 parts of phosphoric acid, 5 parts of a dispersant, 5 parts of a film-forming agent, 5 parts of a leveling agent, 5 parts of an anti-settling agent, 5 parts of an anti-foaming agent, 5 parts of a thickening agent.

[0046] Example 5 A composition of a thermal regulation coating, including water and a slurry matrix. By weight, the slurry matrix includes: 18 parts of the high-entropy ceramic powder in Example 1; The slurry matrix further includes: 7 parts of a phosphate solution of 40 - 50 wt%, 8 parts of an aluminum-based sol, 4 parts of a borate glass powder, 4 parts of aluminum nitride powder, 4 parts of tetrabutyl titanate, 4 parts of zinc phosphate, 4 parts of a dispersant, 4 parts of a film-forming agent, 4 parts of a leveling agent, 4 parts of an anti-settling agent, 4 parts of an anti-foaming agent, 4 parts of a thickening agent.

[0047] Example 6 A composition of a thermal regulation coating, including water and a slurry matrix. By weight, the slurry matrix includes: 25 parts of the high-entropy ceramic powder in Example 1; The slurry matrix further includes: 10 parts of 40-50wt% phosphate solution, 12 parts of aluminum-based sol, 6 parts of phosphate glass powder, 6 parts of aluminum nitride powder, 6 parts of tetrabutyl titanate, 6 parts of triammonium phosphate, 6 parts of dispersant, 6 parts of film-forming agent, 6 parts of leveling agent, 6 parts of anti-settling agent, 6 parts of defoaming agent, and 6 parts of thickener.

[0048] Example 7 A composition of a heat regulating coating, comprising water and a slurry matrix, wherein the slurry matrix comprises, by weight: 50 parts of the high entropy ceramic powder in Example 1; The slurry matrix also includes: 20 parts of 40-50wt% phosphate solution, 20 parts of aluminum-based sol, 10 parts of silicate glass powder, 10 parts of aluminum nitride powder, 10 parts of tetrabutyl titanate, 10 parts of phosphoric acid, 5 parts of dispersant, 5 parts of film-forming agent, 5 parts of leveling agent, 5 parts of anti-settling agent, 5 parts of defoaming agent, and 5 parts of thickener.

[0049] Example 8 A composition of a heat regulating coating, comprising water and a slurry matrix, wherein the slurry matrix comprises, by weight: 5 parts of the high entropy ceramic powder in Example 1; The slurry matrix also includes: 5 parts of 40-50wt% phosphate solution, 5 parts of aluminum-based sol, 2 parts of silicate glass powder, 2 parts of aluminum nitride powder, 2 parts of tetrabutyl titanate, 2 parts of phosphoric acid, 5 parts of dispersant, 5 parts of film-forming agent, 5 parts of leveling agent, 5 parts of anti-settling agent, 5 parts of defoaming agent, and 5 parts of thickener.

[0050] Example 9 A method for preparing a heat regulating coating comprises the following steps: Step S21, preparing a first mixed slurry, at 60° C., uniformly mixing 10 parts of the aluminum-based sol in Example 4, 8 parts of a phosphate solution, 5 parts of phosphoric acid and water to obtain the first mixed slurry; Step S22, preparing a second mixed slurry, adding 5 parts of silicate glass powder, 20 parts of high entropy ceramic powder, and 5 parts of aluminum nitride powder in Example 4 to the first mixed slurry prepared in step S21, and dispersing for 1 hour to prepare the second mixed slurry; Step S23, preparing a third mixed slurry, the step comprising: Add 5 parts of tetrabutyl titanate in Example 4 to the second mixed slurry obtained in step S22, and stir for the first time at 1000 r / min for 2.5 h at a temperature of 60° C., and then cool; After cooling, 5 parts of the dispersant, 5 parts of the film-forming agent, 5 parts of the leveling agent, 5 parts of the anti-settling agent, 5 parts of the defoaming agent, and 5 parts of the thickening agent in Example 4 were added, and the mixture was stirred for the second time at 1000 r / min for 2.5 h at room temperature to obtain the third mixed slurry. Step S24, roll pressing: The third mixed slurry in Step S23 was roll pressed to 10 μm using a three-roll mill to obtain the heat-regulating coating.

[0051] Example 10 A preparation method of a heat-regulating coating includes the following steps: Step S21, preparing the first mixed slurry: At 40 °C, 8 parts of the aluminum-based sol, 7 parts of the phosphate solution, 4 parts of zinc phosphate, and water in Example 5 were uniformly mixed to obtain the first mixed slurry. Step S22, preparing the second mixed slurry: 4 parts of the borate glass powder, 18 parts of the high-entropy ceramic powder, and 4 parts of the aluminum nitride powder in Example 5 were added to the first mixed slurry obtained in Step S21 and dispersed for 0.5 h to obtain the second mixed slurry. Step S23, preparing the third mixed slurry, which includes: 4 parts of tetrabutyl titanate in Example 5 were added to the second mixed slurry obtained in Step S22, and the mixture was stirred for the first time at 500 r / min for 1 h at a temperature of 40 °C and then cooled. After cooling, 4 parts of the dispersant, 4 parts of the film-forming agent, 4 parts of the leveling agent, 4 parts of the anti-settling agent, 4 parts of the defoaming agent, and 4 parts of the thickening agent in Example 5 were added, and the mixture was stirred for the second time at 500 r / min for 1 h at room temperature to obtain the third mixed slurry. Step S24, roll pressing: The third mixed slurry in Step S23 was roll pressed to 10 μm using a three-roll mill to obtain the heat-regulating coating.

[0052] Example 11 A preparation method of a heat-regulating coating includes the following steps: Step S21, preparing the first mixed slurry: At 80 °C, 12 parts of the aluminum-based sol, 10 parts of the phosphate solution, 6 parts of ammonium phosphate, and water in Example 6 were uniformly mixed to obtain the first mixed slurry. Step S22, preparing the second mixed slurry: 6 parts of the phosphate glass powder, 25 parts of the high-entropy ceramic powder, and 6 parts of the aluminum nitride powder in Example 6 were added to the first mixed slurry obtained in Step S21 and dispersed for 1 h to obtain the second mixed slurry. Step S23, preparing the third mixed slurry, which includes: Add 6 parts of tetrabutyl titanate in Example 6 to the second mixed slurry obtained in step S22, and under the temperature condition of 80 °C, stir for the first time at 2000 r / min for 4 h, and then cool down; After cooling, add 6 parts of dispersant, 6 parts of film-forming agent, 6 parts of leveling agent, 6 parts of anti-settling agent, 6 parts of defoaming agent, and 6 parts of thickening agent in Example 6, and stir for the second time at 2000 r / min for 4 h at room temperature to obtain the third mixed slurry; Step S24, roll pressing, use a three-roll mill to roll the third mixed slurry in step S23 to 10 μm to obtain the heat-regulating coating.

[0053] Example 12 A preparation method of a heat-regulating coating, comprising the following steps: Step S21, prepare the first mixed slurry. At 60 °C, uniformly mix 20 parts of the aluminum-based sol in Example 7, 20 parts of the phosphate solution, 10 parts of phosphoric acid, and water to obtain the first mixed slurry; Step S22, prepare the second mixed slurry. Add 10 parts of silicate glass powder, 50 parts of high-entropy ceramic powder, and 10 parts of aluminum nitride powder in Example 7 to the first mixed slurry obtained in step S21, and disperse for 1 h to obtain the second mixed slurry; Step S23, prepare the third mixed slurry, and this step includes: Add 10 parts of tetrabutyl titanate in Example 4 to the second mixed slurry obtained in step S22, and under the temperature condition of 60 °C, stir for the first time at 1000 r / min for 2.5 h, and then cool down; After cooling, add 5 parts of dispersant, 5 parts of film-forming agent, 5 parts of leveling agent, 5 parts of anti-settling agent, 5 parts of defoaming agent, and 5 parts of thickening agent in Example 7, and stir for the second time at 1000 r / min for 2.5 h at room temperature to obtain the third mixed slurry; Step S24, roll pressing, use a three-roll mill to roll the third mixed slurry in step S23 to 10 μm to obtain the heat-regulating coating.

[0054] Example 13 A preparation method of a heat-regulating coating, comprising the following steps: Step S21, prepare the first mixed slurry. At 60 °C, uniformly mix 5 parts of the aluminum-based sol in Example 8, 5 parts of the phosphate solution, 2 parts of phosphoric acid, and water to obtain the first mixed slurry; Step S22: Prepare the second mixed slurry. Add 2 parts of the silicate glass powder, 5 parts of the high-entropy ceramic powder, and 2 parts of the aluminum nitride powder in Example 8 to the first mixed slurry obtained in Step S21, and disperse for 1 h to obtain the second mixed slurry. Step S23: Prepare the third mixed slurry. This step includes: Add 2 parts of tetrabutyl titanate in Example 4 to the second mixed slurry obtained in Step S22, and under the temperature condition of 60 °C, stir for the first time at 1000 r / min for 2.5 h, and then cool. After cooling, add 5 parts of the dispersant, 5 parts of the film-forming agent, 5 parts of the leveling agent, 5 parts of the anti-settling agent, 5 parts of the defoaming agent, and 5 parts of the thickening agent in Example 8, and stir for the second time at 1000 r / min for 2.5 h at room temperature to obtain the third mixed slurry. Step S24: Roll pressing. Use a three-roll mill to roll the third mixed slurry in Step S23 to 10 μm to obtain the thermal regulation coating.

[0055] Application Example In this application example, XRD tests were carried out on some of the high-entropy ceramics prepared in Example 1 and related examples, and FT-IR and heating performance tests were carried out on the thermal regulation coating prepared in Example 9.

[0056] Among them, the test instrument for X-ray diffraction analysis technology (XRD) is a D8 VENTURE X-ray single crystal diffractometer (Bruker Corporation, Germany). The XRD test process is as follows: Grind the sample into fine powder with an agate mortar and then carry out the XRD test.

[0057] The test instrument for infrared radiation performance test (FT-IR) is a NICOLET IS50 infrared spectrometer (ThermoFisher Company). The FT-IR test process is as follows: Coat the thermal regulation coating on a microcrystalline glass plate, after baking is completed, polish it until the surface is uniform and flat, and then carry out the infrared radiation performance test under normal temperature conditions.

[0058] The test instrument for the heating performance test is an electrical test platform, which consists of a regulated power supply, a voltage regulator, and an infrared probe. The heating performance test process is as follows: Coat the coating on a microcrystalline glass plate, brush silver paste on both sides of the coating on the microcrystalline glass plate to make electrodes. Specifically, first fix the infrared probe on the bracket and connect it to the computer, secondly clamp the test clips on the silver paste electrodes on both sides of the microcrystalline glass plate, connect them to the circuit, and form a loop. Finally, adjust the input voltage and record various parameters of the component to be measured under different voltage conditions.

[0059] The XRD patterns of the high-entropy ceramics prepared in Example 1 and related examples are as Figures 1-3As shown, the test results are shown in Table 1. The test results of the heat regulation coating prepared in Example 9 are shown in Table 2.

[0060] Table 1 XRD analysis results of high-entropy ceramics Table 2 Heat generation test results of heat regulation coating As Figure 1 、 Figure 2 and Figure 3 shown, the test results of XRD all show that the diffraction peak pattern of the sample is sharp, and there are no diffraction peaks of other crystal structures in the spectrum, indicating that in Example 1 and related examples of the present application, when the ratio of reactants is fixed, there is a single phase in the prepared high-entropy ceramic sample, and there are no other phases, that is, all components (strontium, manganese, titanium, copper, cobalt) are successfully doped into lanthanum ferrite and enter the lattice to form a single solid solution structure of (La 0.8 Sr 0.2 )(Mn x Ti y Cu z Co m Fe 1-x-y-z-m )O3, and it is a perovskite structure. After calcination at different temperatures, the composition remains unchanged, and the high-entropy ceramic has high stability at high temperatures. The statistical results are shown in Table 1.

[0061] It can be seen from Examples 1-3 that by keeping other conditions unchanged and changing the ratio of reactants, the high-entropy ceramic powder can also be prepared, and the structural formula of the high-entropy ceramic powder can all conform to (La 0.8 Sr 0.2 )(Mn x Ti y Cu z Co m Fe 1-x-y-z-m )O3.

[0062] It can be seen from Table 2 that when the external circuit voltage is increased from 20V to 100V, the surface temperature of the heat regulation coating prepared in Example 9 increases from 30.1°C to 115.8°C. By adjusting the external voltage, the heating temperature of the heat regulation coating can be controlled. When the heating temperature is set to 110°C, the power required per square meter is 0.285W, which is relatively energy-saving; from the relationship between temperature and resistance, the resistance of the test material prepared by the heat regulation coating decreases with the increase of temperature, that is, the test material prepared by the heat regulation coating belongs to a negative temperature coefficient material. The infrared performance test results show that the infrared radiation coefficient of the heat regulation coating in Example 9 in the 8-14μm band is 0.9, and the performance is excellent.

[0063] The thermal regulation coating described in this application has excellent low and medium band infrared radiation performance, can be used to assist the heat dissipation of power devices, especially in injection molds, to improve the reliability of the molds, and has great application potential in the field of variable temperature injection molds.

[0064] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the examples, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A method for preparing high-entropy ceramic powder, characterized in that, It includes the following steps: Step S11, preparing a first mixed solution: By mass parts, add 1 to 50 parts of manganese carbonate and 1 to 50 parts of strontium carbonate into water. After stirring evenly, add 30 to 40 parts of a first inorganic acid and dissolve until there is no precipitate, thus obtaining the first mixed solution; Step S12, preparing a second mixed solution: Add 100 to 500 parts of lanthanum nitrate, 1 to 40 parts of copper nitrate, 5 to 200 parts of iron nitrate, and 1 to 100 parts of cobalt nitrate into the first mixed solution obtained in step S11, thus obtaining the second mixed solution; Step S13, preparing a synthesis solution, which includes: Add 1 to 200 parts of tetrabutyl titanate into the second mixed solution obtained in step S12. After heating to 55 to 65 °C, add a second inorganic acid and stir for 1 to 3 h; Then adjust the pH value to 4 to 8; and keep warm for 1 to 3 h; After that, keep warm at a temperature of 50 to 90 °C for 10 to 15 h to obtain the synthesis solution; Step S14, evaporating to dryness and burning, which includes: Evaporate the synthesis solution obtained in step S13 to dryness with stirring at a temperature of 95 to 105 °C to obtain a gel-like material; Ignite the gel-like material to obtain a black material; Step S15, calcining: Calcine the black material obtained in step S14 at a temperature of 600 to 1000 °C for 1 to 3 h to obtain the high-entropy ceramic powder.

2. The method for preparing the high-entropy ceramic powder according to claim 1, wherein in step S11, preparing the first mixed solution includes: By mass parts, add 2 to 30 parts of manganese carbonate and 5 to 40 parts of strontium carbonate into water. After stirring evenly, add 30 to 40 parts of a first inorganic acid and dissolve until there is no precipitate, thus obtaining the first mixed solution; and / or, in step S12, preparing the second mixed solution includes: Add 200 to 300 parts of lanthanum nitrate, 2 to 25 parts of copper nitrate, 20 to 100 parts of iron nitrate, and 5 to 50 parts of cobalt nitrate into the first mixed solution obtained in step S11, thus obtaining the second mixed solution; and / or, in step S13: the "add 1 to 200 parts of tetrabutyl titanate into the second mixed solution obtained in step S12. After heating to 55 to 65 °C, add a second inorganic acid and stir for 1 to 3 h" includes: add 10 to 110 parts of tetrabutyl titanate into the second mixed solution obtained in step S12. After heating to 55 to 65 °C, add a second inorganic acid and stir for 1 to 3 h; and / or, the "then adjust the pH value to 4 to 8; and keep warm for 1 to 3 h" includes: then adjust the pH value to 4 to 8; and keep warm for 1 to 3 h; and / or, the "after that, keep warm at a temperature of 50 to 90 °C for 10 to 15 h to obtain the synthesis solution" includes: after that, keep warm at a temperature of 75 to 85 °C for 10 to 15 h to obtain the synthesis solution; and / or, in step S14: the "evaporate the synthesis solution obtained in step S13 to dryness with stirring at a temperature of 95 to 105 °C to obtain a gel-like material" includes: Evaporate the synthesis solution with stirring at a temperature of 95 - 105 °C in step S13 to obtain a gel-like material; Ignite the gel-like material to obtain a black material; And / or, in step S15, calcine: calcine the black material obtained in step S14 at a temperature of 600 - 1000 °C for 1 - 3 h to obtain the high-entropy ceramic powder.

3. The method for preparing the high-entropy ceramic powder according to claim 2, wherein In step S11, the first inorganic acid includes nitric acid; And / or, in step S13, the second inorganic acid includes citric acid; And / or, in step S13, the pH value is adjusted to 4 - 8 with concentrated ammonia water.

4. A high-entropy ceramic powder, characterized in that, Prepared by using the method for preparing the high-entropy ceramic powder according to any one of claims 1 - 3.

5. A composition of a heat-regulating coating, the heat-regulating coating comprising water and a slurry matrix, characterized in that, By weight, the slurry matrix includes: 5 - 50 parts of the high-entropy ceramic powder according to claim 4; The slurry matrix further includes: 5 - 20 parts of phosphate solution, 5 - 20 parts of inorganic sol, 2 - 10 parts of glass powder, 2 - 10 parts of aluminum nitride powder, 2 - 10 parts of tetrabutyl titanate, 2 - 10 parts of high-temperature antioxidant, 2 - 10 parts of dispersant, 2 - 10 parts of film-forming agent, 2 - 10 parts of leveling agent, 2 - 10 parts of anti-settling agent, 2 - 10 parts of defoaming agent, 2 - 10 parts of thickening agent.

6. The composition of the heat-regulating coating according to claim 5, wherein the heat-regulating coating comprises water and a slurry matrix, characterized in that, By weight, the slurry matrix includes: 15 - 25 parts of the high-entropy ceramic powder according to claim 4; The slurry matrix further includes: 7 - 10 parts of 40 - 50 wt% phosphate solution, 8 - 12 parts of inorganic sol, 4 - 6 parts of glass powder, 4 - 6 parts of aluminum nitride powder, 4 - 6 parts of tetrabutyl titanate, 4 - 6 parts of high-temperature antioxidant, 4 - 6 parts of dispersant, 4 - 6 parts of film-forming agent, 4 - 6 parts of leveling agent, 4 - 6 parts of anti-settling agent, 4 - 6 parts of defoaming agent, 4 - 6 parts of thickening agent.

7. The composition of the heat-regulating coating according to claim 6, wherein The inorganic sol includes aluminum-based sol; And / or, the solute of the phosphate solution includes aluminum dihydrogen phosphate and aluminum chromium phosphate; And / or, the glass powder is selected from one or more of silicate, borate, silicon boron, and phosphate glass; And / or, the high-temperature antioxidant is selected from one or more of phosphoric acid, zinc phosphate, ammonium phosphate tribasic, and boric acid; Wherein, the pH value of the aluminum-based sol is 5 - 7 and / or the particle size of the colloidal particles of the aluminum-based sol is 20 - 80 nm.

8. A preparation method of a thermal regulation coating, characterized in that, Includes the following steps: Step S21, prepare the first mixed slurry: at 40 - 80 °C, uniformly mix the aluminum-based sol, phosphate solution, high-temperature antioxidant, and water in the composition of the heat-regulating coating according to any one of claims 4 - 7 to obtain the first mixed slurry; Step S22, prepare the second mixed slurry: add the glass powder, high-entropy ceramic powder, and aluminum nitride powder in the composition of the heat-regulating coating according to any one of claims 4 - 6 to the first mixed slurry obtained in step S21, and disperse for 0.5 - 1 h to obtain the second mixed slurry; Step S23, prepare the third mixed slurry, this step includes: Add tetrabutyl titanate in the composition of the thermal regulation coating according to any one of claims 4 to 6 to the second mixed slurry obtained through step S22, and conduct the first stirring under the temperature condition of 40 to 80 °C, and then cool down; After cooling, add the dispersant, film-forming agent, leveling agent, anti-settling agent, defoaming agent, and thickening agent in the composition of the thermal regulation coating according to any one of claims 4 to 6, and conduct the second stirring at room temperature to obtain the third mixed slurry; Step S24, roll pressing: Roll and press the third mixed slurry obtained through step S23 to obtain the thermal regulation coating.

9. A heat-regulating coating, characterized in that, It is obtained by using the preparation method of the thermal regulation coating according to claim 8.

10. Application of the thermal regulation coating according to claim 9 in an injection mold.

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