Ablative-resistant coating and its use

Abstract

The application provides an ablation-resistant coating and application thereof, and belongs to the technical field of coating.The ablation-resistant coating is prepared by using lignin fiber, silicone rubber, ablation filler and ablation filler as raw materials, and overcomes the problem of ablation bulging and cracking of the ablation-resistant coating in the prior art in the application process.The ablation-resistant coating has excellent ablation resistance and mechanical properties, can utilize the characteristics that the lignin fiber can be ablated at a lower temperature and the silicone rubber can be cracked in the ablation process, form a pore channel with good connectivity before the gas escapes from the coating, and has good compatibility with the overall coating formula, is uniformly dispersed in the material, so that the ablation-resistant coating can retain a relatively uniform pore channel after ablation, and is not prone to local bulging and cracking, thereby widening the application situation of the ablation-resistant coating and optimizing the use effect of the coating product.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of coating technology, in particular to a kind of ablation-resistant coating and its application. BACKGROUND

[0002] Ablation-resistant coating is a kind of coating specially used for high temperature environment, it has excellent heat resistance and excellent protection characteristics. In many industrial fields, such as automobile manufacturing, petrochemical industry, aerospace and energy production, ablation-resistant coating plays an important role. In some special scenarios, ablation-resistant coating needs to withstand 800℃ or even 1000℃ or more high temperature airflow scouring, oxidation and gas corrosion and other harsh environments, which requires the outer heat-resistant coating to have excellent high temperature scouring resistance and ablation resistance.

[0003] The prior art discloses a variety of ablation type heat-resistant coating, mainly with resin / rubber as matrix material, using the characteristics of resin / rubber cracking heat absorption under high temperature to take away a large amount of aerodynamic heat, so as to protect the object from the influence of high temperature aerodynamic heat environment, and ensure its normal operation. For example, a fireproof coating disclosed in Chinese patent CN102977712A uses weather-resistant acrylic resin, chloroether resin and 586 flame-retardant amino resin as main components to achieve the effect of fireproof and ablation-resistant.

[0004] However, because such materials will produce a large amount of gas escaping during ablation under high temperature, when the gas escaping channel is less or unevenly distributed, the gas escaping is blocked locally, which is easy to form bulging or cracking phenomenon in the coating, which will significantly reduce the ablation resistance and thermal insulation of the heat-resistant coating. In order to solve the problem of easy bulging or cracking of the coating during ablation, some researchers use the way of improving the interfacial adhesion strength, improving the uniformity of material structure, reducing the amount of solvent added, adding a large amount of organic fibers such as carbon fibers or aramid fibers to the coating, but it cannot fundamentally solve the problem, on the contrary, it may cause the ablation bulging phenomenon to be intensified or the ablation resistance to be insufficient. SUMMARY

[0005] The purpose of the present application is to provide an ablation-resistant coating and its application, to solve the problem of ablation bulging and cracking of the ablation-resistant coating in the prior art during application.

[0006] In order to achieve the above-mentioned purpose of the application, the present application provides the following technical scheme:

[0007] The present application provides an ablation-resistant coating, which is made of raw materials including the following mass fractions:

[0008] 1-20 parts of lignin fiber;

[0009] 80-120 parts of silicone rubber;

[0010] 20-80 parts of ablation filler;

[0011] 5-30 parts of fibrous filler;

[0012] 5-30 parts of auxiliary agent;

[0013] 200-300 parts of solvent.

[0014] Preferably, the silicone rubber is selected from one or more of methyl silicone rubber, vinyl silicone rubber and phenyl silicone rubber.

[0015] Preferably, the ablative filler is selected from one or more of hollow microbead, high-hardness inorganic filler and light-weight porous filler.

[0016] Preferably, the hollow microbead is selected from one or more of hollow glass microsphere, hollow phenolic microsphere, hollow ceramic microsphere and hollow zirconium bead.

[0017] Preferably, the high-hardness inorganic filler is selected from one or more of glass powder, barium sulfate powder, silica powder, whisker silicon powder, whisker calcium powder, mica powder and silicon micro-powder.

[0018] Preferably, the light-weight porous filler is selected from one or more of expanded perlite, expanded vermiculite, diatomite, bamboo charcoal and kaolin.

[0019] Preferably, the fibrous filler is selected from one or more of chopped quartz fiber, chopped glass fiber, high-silica fiber and mullite fiber.

[0020] Preferably, the auxiliary agent includes one or more of film-forming agent, defoaming agent, leveling agent, thickening agent, dispersing agent, cross-linking agent and catalyst.

[0021] The preparation method of the ablative coating preferably comprises the following steps:

[0022] All raw materials are mixed at one time or in batches, and the viscosity of the final product is adjusted to 15-25 Pa·s, to obtain the ablative coating.

[0023] The application also provides the use of the above-mentioned ablative coating in the protection of industrial equipment and pipelines, the coating of inner walls of high-temperature furnaces, the engine and exhaust system of vehicles, aerospace, the fireproofing of steel structures or high-temperature processing equipment in environmental engineering.

[0024] The application also provides a coated substrate, comprising a substrate and the above-mentioned ablative coating coated on at least a part of the substrate, and the substrate is made of metal, glass fiber composite material, organic aramid composite material or high-strength medium-modulus carbon fiber composite material.

[0025] The application has the following advantages:

[0026] The present application uses lignin fiber, silicone rubber, ablative filler and fiber filler as raw materials in specific weight proportions, so that the prepared ablative-resistant coating has excellent ablative-resistant and mechanical properties. The present application uses the characteristics that lignin fiber can be lost at a lower temperature and silicone rubber can be cracked during the ablation process to form a well-connected pore channel before the gas escapes in the coating, and then combines the overall coating formula to have good compatibility, so that each component is uniformly dispersed in the material, so that the ablative-resistant coating can retain a relatively uniform pore channel after ablation, and is not prone to local bulging and cracking. The ablative-resistant coating formula provided by the present application can produce a pore channel, so that the coating can promote uniform solvent evaporation and air moisture transmission into the coating, further reduce the internal stress caused by uneven solidification of the coating, and broaden the application situation of the ablative-resistant coating and optimize the use effect of the coating product. BRIEF DESCRIPTION OF DRAWINGS

[0027] Fig. 1 The apparent morphology diagram of the sample of Example 1 after micro-wind tunnel detection;

[0028] Fig. 2 The apparent morphology diagram of the sample of Example 2 after micro-wind tunnel detection;

[0029] Fig. 3 The apparent morphology diagram of the sample of Comparative Example 1 after micro-wind tunnel detection. DETAILED DESCRIPTION

[0030] The present application provides an ablative-resistant coating, which is made of raw materials including the following mass fractions: 1-20 parts of lignin fiber, 80-120 parts of silicone rubber, 20-80 parts of ablative filler, 5-30 parts of fiber filler, 5-30 parts of auxiliary agent and 200-300 parts of solvent.

[0031] In the present application, the raw materials of the ablative-resistant coating include 1-20 parts of lignin fiber, the fiber length of the lignin fiber is 200-1000 μm, the lignin fiber has the characteristics of being lost at a lower temperature, and can form a well-connected pore channel in the coating before the gas escapes during the ablation process in combination with the cracking characteristics of the silicone rubber, thereby avoiding the bulging or cracking of the coating caused by the local obstruction of the gas escape; in the present application, the mass fraction of the lignin fiber is preferably 3-15 parts, and further preferably 5-12 parts, and the addition amount of the lignin fiber is too small to cause uneven surface of the coating, and too much to affect the mechanical properties of the coating, and the addition amount given in the present application can achieve the best effect.

[0032] In the present application, the raw materials of the ablation-resistant coating include 80-120 parts of silicone rubber, which is preferably one or more of methyl silicone rubber, vinyl silicone rubber and phenyl silicone rubber; the silicone rubber will crack during the ablation process, and in combination with the lignin fibers in the above, the ablation-resistant coating can form a good gas pore channel in the coating before the gas escapes, thereby avoiding the local obstruction of gas escape leading to the bulging or cracking of the coating; in the present application, the mass fraction of the silicone rubber is preferably 90-110 parts, and further preferably 95-105 parts; the addition of less silicone rubber will affect the mechanical properties of the coating, and the addition of more silicone rubber will reduce the adhesion of the coating; the addition amount given in the present application can achieve the best effect.

[0033] In the present application, the raw materials of the ablation-resistant coating include 20-80 parts of ablation filler, which is preferably one or more of hollow microbeads, high-hardness inorganic filler and light porous filler, and more preferably a combination of hollow microbeads, high-hardness inorganic filler and light porous filler; when hollow microbeads, high-hardness inorganic filler and light porous filler are used in combination, the weight ratio of hollow microbeads, high-hardness inorganic filler and light porous filler in the ablation filler is preferably 3-5:1:2-4.

[0034] In the present application, the hollow microbeads are preferably one or more of hollow glass microspheres, hollow phenolic microspheres, hollow ceramic microspheres and hollow zirconium beads,

[0035] The high-hardness inorganic filler is preferably one or more of glass powder, barium sulfate powder, silica powder, whisker silicon powder, whisker calcium powder, mica powder and silicon micro powder,

[0036] The light porous filler is preferably one or more of expanded perlite, expanded vermiculite, diatomite, bamboo charcoal and kaolin;

[0037] The ablation filler in the present application can undergo physical and chemical changes such as decomposition, melting, evaporation, sublimation and erosion under the action of heat flow, and can take away a large amount of heat by consuming the mass of the material surface, thereby playing a role in ablation resistance; the mass fraction of the ablation filler is preferably 30-70 parts; the types and addition amount of the ablation filler provided in the present application can achieve the best ablation-resistant effect, have good compatibility as a whole, disperse uniformly in the material, and can retain a relatively uniform gas pore channel after ablation, further preventing the bulging or cracking of the coating.

[0038] In the present application, the raw materials of the ablation-resistant coating include 5-30 parts of fiber fillers, preferably one or more of chopped quartz fiber, chopped glass fiber, high-silica fiber and mullite fiber; the fiber fillers can increase the strength and hardness of the coating, can also increase the adhesion of the coating in combination with lignin fiber and silicone rubber, further prevent the coating from cracking and hollowing, and can cooperate with other components to improve the rheological properties and emulsification stability of the ablation-resistant coating, which is beneficial to the application of the ablation-resistant coating; the mass fraction of the fiber fillers is preferably 10-25 parts, and further preferably 15-20 parts, and the fiber fillers can achieve the optimal effect in the addition amount given in the present application.

[0039] In the present application, the raw materials of the ablation-resistant coating include 5-30 parts of additives, preferably one or more of film-forming agent, defoaming agent, leveling agent, thickening agent, dispersing agent, crosslinking agent and catalyst, which can enhance the quality of the ablation-resistant coating.

[0040] The film-forming agent helps the film formation of the coating, reduces the porosity of the coating, improves the wear resistance, water washing resistance and gloss of the coating, and can be selected from polyvinyl formal, polyvinyl butylal, polyvinyl alcohol, collodion, corn protein, sodium carboxymethyl cellulose, polyvinyl pyrrolidone, dibutyl phthalate, glycerol, propylene glycol, sorbitol or mannitol, etc., and the addition amount of the film-forming agent is not more than 1wt% of the total weight of the ablation-resistant coating in the present application.

[0041] The defoaming agent is not soluble in the coating foam system, and the defoaming agent component is dispersed into the foam interior by dispersibility, or uniformly diffused on the surface of the coating foam by ductility, to achieve defoaming and improve the uniformity of the coating, and can be selected from mineral oil coating defoaming agent, polyether coating defoaming agent or silicone coating defoaming agent, etc., and the addition amount of the defoaming agent is not more than 1wt% of the total weight of the ablation-resistant coating in the present application.

[0042] The leveling agent can help the powder coating film to present a smooth and flat state after construction, and the surface does not have irregular shapes such as orange peel, brush marks, corrugation, shrinkage, etc., and can be selected from acrylic ester homopolymer, acrylic copolymer, silicone-modified acrylic polymer and polysiloxane, etc., and the addition amount of the leveling agent is not more than 1wt% of the total weight of the ablation-resistant coating in the present application.

[0043] The thickening agent can improve the viscosity and viscosity of the coating, making it easier to construct, and can be selected from fumed silica, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, hydroxypropyl methyl cellulose, sodium polyacrylate, organic bentonite, polyacrylamide, guar gum, xanthan gum or other composite thickening agents, etc., and the addition amount of the thickening agent is not more than 1wt% of the total weight of the ablation-resistant coating in the present application.

[0044] The cross-linking agent can chemically react with molecules in the paint to form a cross-linked structure, thereby enhancing the hardness, wear resistance and chemical corrosion resistance of the paint. In the present application, the cross-linking agent can be selected from one or more of multifunctional alkoxysilane and siloxane cross-linking agent, ketoxime silane cross-linking agent, allyloxy silane cross-linking agent, amido silane and siloxane cross-linking agent, aminooxy silane and siloxane cross-linking agent. The addition amount of the cross-linking agent is not more than 5wt% of the total weight of the ablation-resistant paint.

[0045] The catalyst can initiate a chemical reaction in the paint system to improve the performance and construction efficiency of the paint. In the present application, the catalyst can be selected from one or more of organic tin catalyst, titanate and its complex catalyst, guanidino hydroxyalkoxy silane catalyst. The addition amount of the catalyst is not more than 1wt% of the total weight of the ablation-resistant paint.

[0046] The raw materials of the ablation-resistant paint also preferably include pigments, which impart color to the paint and do not participate in changing the physical and chemical properties of the ablation-resistant paint. The pigments can be selected from titanium white, zinc barytes, zinc white, antimony white, chromium yellow, iron oxide yellow, cadmium yellow, chromium oxide green, chromium green, iron blue, ultramarine, iron red, cadmium red, molybdenum chromium red, carbon black, iron black, etc. The addition amount of the pigments is not more than 20wt% of the total weight of the ablation-resistant paint.

[0047] The dispersant, also known as wet dispersant, has a wetting effect on one hand, and on the other hand, its active group can be adsorbed on the surface of the pigment crushed into fine particles, and the other end is solvated into the base to form an adsorption layer (the more adsorption groups and the longer the chain, the thicker the adsorption layer), generating charge repulsion (water-based paint) or entropy repulsion (solvent-based paint), so that the pigment particles are dispersed and suspended in the paint for a long time, avoiding re-flocculation, thereby ensuring the storage stability of the prepared color paint system. The addition amount of the dispersant is not more than 1wt% of the total weight of the ablation-resistant paint.

[0048] The raw materials of the ablation-resistant paint also preferably include antioxidants, which can improve the anti-aging and durability of the coating. The antioxidant is preferably a phenolic antioxidant or a thiol antioxidant. The addition amount of the antioxidant is not more than 2wt% of the total weight of the ablation-resistant paint.

[0049] In the present application, the raw materials of the ablation-resistant coating include 200-300 parts of solvent, which is preferably one or more of pine oil, pine tar, petroleum solvent, coal tar solvent, ester solvent, ketone solvent, alcohol solvent, chlorine-containing solvent, nitroalkane solvent, ether alcohol solvent, more preferably No. 120 solvent oil, ethyl acetate or xylene, which can dissolve and dilute the film-forming substances in the raw materials, reduce the viscosity of the paint, facilitate construction, and also increase the stability of the coating storage; the weight fraction of the solvent is preferably 230-270 parts, and further preferably 240-260 parts.

[0050] The present application also provides the application of the above-mentioned ablation-resistant coating in industrial equipment and pipeline protection, high-temperature furnace kiln inner wall coating, vehicle engine and exhaust system, aerospace, steel structure fireproofing or environmental engineering high-temperature treatment equipment, further preferably in the field of aerospace, and more preferably in the heat-resistant coating of high-speed aircraft, which can achieve ablation-resistant effect in the ablation caused by high-speed flight and avoid coating bulging and cracking.

[0051] The present application also provides a coated substrate, which includes a substrate and the above-mentioned ablation-resistant coating coated on at least a part of the substrate, and the material of the substrate is metal, glass fiber composite material, organic aramid composite material or high-strength medium-modulus carbon fiber composite material.

[0052] The technical solutions provided by the present application will be described in detail below in combination with examples, but they should not be understood as limiting the scope of protection of the present application.

[0053] Example 1

[0054] 100 parts of phenyl silicone rubber, 5 parts of diatomite, 5 parts of low-melting-point glass powder, 20 parts of fumed silica, 5 parts of amide-based silane crosslinking agent and 100 parts of No. 120 solvent oil are uniformly mixed, and then ground by a sand mill to prepare component A; 20 parts of hollow glass microbeads, 10 parts of expanded vermiculite, 15 parts of chopped quartz fiber, 3 parts of lignin fiber, 1 part of organic tin catalyst and 200 parts of No. 120 solvent oil are uniformly mixed to prepare component B; components A and B are uniformly mixed, the viscosity is measured by a four-cup coating to reach 20 Pa·s, and a small-sized brake spraying equipment is used for sample preparation (the thickness of the sample is 5 mm); after the sample is cured at room temperature for 7 days, the related performance test is carried out.

[0055] Example 2

[0056] A component is prepared by mixing 80 parts of phenyl silicone rubber, 5 parts of diatomite, 5 parts of low-melting-point glass powder, 15 parts of fumed silica, 3 parts of ketoxime silane crosslinking agent and 80 parts of No. 120 solvent oil uniformly, and then grinding by using a sand mill; B component is prepared by mixing 15 parts of hollow glass microbeads, 10 parts of expanded vermiculite, 10 parts of short-cut quartz fiber, 10 parts of lignin fiber, 0.5 part of guanidino hydroxy alkoxysilane catalyst and 150 parts of No. 120 solvent oil uniformly; A and B components are mixed uniformly, and the viscosity is measured by using a four-cup coater to reach 20 Pa·s, and a small-sized brake spraying device is used to spray and prepare a sample (the sample thickness is 2 mm); after the sample is cured at room temperature for 7 days, relevant performance tests are carried out.

[0057] Example 3

[0058] A component is prepared by mixing 90 parts of methyl silicone rubber, 5 parts of expanded perlite, 5 parts of mica powder, 13 parts of hydroxypropyl methyl cellulose, 3 parts of ketoxime silane crosslinking agent and 90 parts of No. 120 solvent oil uniformly, and then grinding by using a sand mill; B component is prepared by mixing 15 parts of hollow glass microbeads, 10 parts of expanded vermiculite, 10 parts of high-silica fiber, 10 parts of lignin fiber, 0.5 part of organic tin catalyst and 150 parts of No. 120 solvent oil uniformly; A and B components are mixed uniformly, and the viscosity is measured by using a four-cup coater to reach 22 Pa·s, and a small-sized brake spraying device is used to spray and prepare a sample (the sample thickness is 8 mm); after the sample is cured at room temperature for 7 days, relevant performance tests are carried out.

[0059] Example 4

[0060] A component is prepared by mixing 115 parts of vinyl silicone rubber, 5 parts of expanded perlite, 5 parts of silica powder, 13 parts of hydroxypropyl methyl cellulose, 3 parts of ketoxime silane crosslinking agent and 120 parts of No. 120 solvent oil uniformly, and then grinding by using a sand mill; B component is prepared by mixing 16 parts of hollow ceramic microbeads, 10 parts of kaolin, 10 parts of short-cut quartz fiber, 12 parts of lignin fiber, 0.5 part of organic tin catalyst and 100 parts of No. 120 solvent oil uniformly; A and B components are mixed uniformly, and the viscosity is measured by using a four-cup coater to reach 22 Pa·s, and a small-sized brake spraying device is used to spray and prepare a sample (the sample thickness is 10 mm); after the sample is cured at room temperature for 7 days, relevant performance tests are carried out.

[0061] Example 5

[0062] Mix 95 parts of phenyl silicone rubber, 4 parts of expanded perlite, 6 parts of whisker silicon powder, 10 parts of methyl cellulose, 2.5 parts of allyloxy silane crosslinking agent, 100 parts of No. 120 xylene uniformly, and then grind by using a sand mill to prepare component A; mix 14 parts of hollow phenolic microbeads, 11 parts of expanded vermiculite, 9 parts of mullite fiber, 9 parts of lignin fiber, 0.5 parts of titanate catalyst and 150 parts of xylene uniformly to prepare component B; mix components A and B uniformly, and the viscosity is 22 Pa·s measured by using a four-cup coating machine, and then sample preparation is performed by using a small braking spraying equipment (the sample thickness is 5 mm); after the sample is cured at room temperature for 7 days, the related performance test is performed.

[0063] Comparative Example 1

[0064] Mix 80 parts of phenyl silicone rubber, 5 parts of diatomite, 5 parts of low-melting-point glass powder, 15 parts of fumed silica, 3 parts of ketoxime silane crosslinking agent and 80 parts of No. 120 solvent oil uniformly, and then grind by using a sand mill to prepare component A; mix 15 parts of hollow glass microbeads, 10 parts of expanded vermiculite, 10 parts of short-cut quartz fiber, 0.5 parts of guanidino hydroxy alkoxysilane catalyst and 150 parts of No. 120 solvent oil uniformly to prepare component B; mix components A and B uniformly, and the viscosity is 20 Pa·s measured by using a four-cup coating machine, and then sample preparation is performed by using a small braking spraying equipment (the sample thickness is 5 mm); after the sample is cured at room temperature for 7 days, the related performance test is performed.

[0065] Comparative Example 2

[0066] Mix 140 parts of phenyl silicone rubber, 5 parts of diatomite, 5 parts of low-melting-point glass powder, 15 parts of fumed silica, 3 parts of ketoxime silane crosslinking agent and 140 parts of No. 120 solvent oil uniformly, and then grind by using a sand mill to prepare component A; mix 15 parts of hollow glass microbeads, 10 parts of expanded vermiculite, 10 parts of short-cut quartz fiber, 10 parts of lignin fiber, 0.5 parts of guanidino hydroxy alkoxysilane catalyst and 150 parts of No. 120 solvent oil uniformly to prepare component B; mix components A and B uniformly, and the viscosity is 20 Pa·s measured by using a four-cup coating machine, and then sample preparation is performed by using a small braking spraying equipment (the sample thickness is 5 mm); after the sample is cured at room temperature for 7 days, the related performance test is performed.

[0067] Comparative Example 3

[0068] 80 parts of chloroether resin, 5 parts of diatomaceous earth, 5 parts of low-melting-point glass powder, 15 parts of fumed silica, 3 parts of ketoxime silane crosslinking agent, and 80 parts of No. 120 solvent oil were mixed evenly and then ground using a sand mill to prepare component A. 15 parts of hollow glass microspheres, 10 parts of expanded vermiculite, 10 parts of chopped quartz fiber, 10 parts of lignin fiber, 0.5 parts of guanidine hydroxyalkoxysilane catalyst, and 150 parts of No. 120 solvent oil were mixed evenly to prepare component B. Components A and B were mixed evenly, and the viscosity was measured to be 20 Pa·s using a Ford cup. Samples were prepared by spraying using a small brake spraying device (sample thickness 5 mm). After the samples were cured at room temperature for 7 days, they were used for relevant performance tests.

[0069] Comparative Example 4

[0070] 80 parts of phenyl silicone rubber, 5 parts of diatomaceous earth, 40 parts of phenolic resin, 15 parts of fumed silica, 3 parts of ketoxime silane crosslinking agent, and 80 parts of No. 120 solvent oil were mixed evenly and then ground using a sand mill to prepare component A. 15 parts of hollow glass microspheres, 10 parts of expanded vermiculite, 10 parts of chopped quartz fiber, 10 parts of lignin fiber, 0.5 parts of guanidine hydroxyalkoxysilane catalyst, and 150 parts of No. 120 solvent oil were mixed evenly to prepare component B. Components A and B were mixed evenly, and the viscosity was measured to be 20 Pa·s using a Ford cup. Samples were prepared by spraying using a small brake spraying device (sample thickness 5 mm). After the samples were cured at room temperature for 7 days, they were used for relevant performance tests.

[0071] Experiment Example 1 Mechanical Property Testing

[0072] The mechanical properties of the embodiments were tested, and the results are shown in Table 1 below:

[0073] Table 1 Physical and mechanical performance test data

[0074]

[0075] The results of the comparative mechanical property tests are shown in Table 2 below:

[0076] Table 2 Physical and mechanical performance test data

[0077]

[0078]

[0079] The mechanical property test data of the comparative examples and embodiments show that the formulation types and dosages provided by the present invention can obtain the best-performing ablation-resistant coatings, achieving optimal material density, tensile strength, hardness, and elongation at break.

[0080] Experiment Example 2: Test of ablation resistance

[0081] The coating provided by the application examples 1-2 and the comparative example 1 is respectively sprayed on an aluminum alloy test plate with a size of 100mm*100mm, and the coating thickness is 5mm. After curing, the dynamic ablation performance of the coating is detected by using a plasma arc micro-wind tunnel device according to the experimental method of GJB7050-2010, and the experimental results are shown in Table 1. Figs. 1-3 Fig. 1 The apparent morphology of the example 1 sample after micro-wind tunnel detection is shown in Figure 1, Fig. 2 The apparent morphology of the example 2 sample after micro-wind tunnel detection is shown in Figure 2, Fig. 3 The apparent morphology of the comparative example 1 sample after micro-wind tunnel detection is shown in Figure 3.

[0082] According to the detection results, compared with the comparative example 1, the coating formed by the ablation-resistant coating provided by the application has no bulging and cracking phenomenon, and the coating surface in the example 2 is more flat. Therefore, the ablation-resistant coating provided by the application can avoid the bulging and cracking of the coating during the ablation process on the basis of retaining the mechanical properties of the coating, and improve the ablation-resistant performance.

[0083] The above only describes the preferred embodiments of the application, and it should be pointed out that for ordinary skilled in the art, without departing from the principles of the application, a number of improvements and refinements can be made, and these improvements and refinements should also be considered as the protection scope of the application.​

Claims

1. An ablative-resistant coating, characterized in that, It is made of the following raw materials in mass fraction: 10~12 parts of lignin fiber; 80~120 parts of silicone rubber; 20~80 parts of ablative filler; 5~30 parts of fiber filler; 5~30 parts of auxiliary agent; 200~300 parts of solvent; The silicone rubber is selected from one or more of methyl silicone rubber, vinyl silicone rubber and phenyl silicone rubber; The ablative filler is hollow microbeads, high-hardness inorganic filler and light porous filler; The hollow microbeads are selected from one or more of hollow glass microspheres, hollow phenolic microspheres, hollow ceramic microspheres and hollow zirconium beads; The light porous filler is selected from one or more of expanded perlite, expanded vermiculite, diatomite, bamboo charcoal and kaolin; The fiber filler is selected from one or more of chopped quartz fiber, chopped glass fiber, high-silica fiber and mullite fiber; The high-hardness inorganic filler is selected from one or more of glass powder, barium sulfate powder, silica powder, calcium whisker powder and mica powder; The fiber length of the lignin fiber is 200-1000 μm.

2. The ablative-resistant coating of claim 1, wherein, The auxiliary agent includes one or more of film-forming agent, defoaming agent, leveling agent, thickening agent, dispersing agent, crosslinking agent and catalyst.

3. Use of the ablative-resistant coating of any one of claims 1~2 in the protection of industrial equipment and pipelines, high-temperature furnace inner wall coating, vehicle engine and exhaust system, aerospace, steel structure fireproofing or environmental engineering high-temperature processing equipment.

4. A coated substrate characterized by, It comprises a substrate and an ablative-resistant coating coated on at least a part of the substrate, wherein the ablative-resistant coating is the ablative-resistant coating of any one of claims 1~2; The material of the substrate is aluminum / titanium alloy, glass fiber composite material, organic aramid composite material or high-strength medium-modulus carbon fiber composite material.

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