Coating with airplane grey and infrared stealth functions and preparation method thereof

Abstract

The invention belongs to the technical field of functional materials, and particularly discloses a coating with airplane grey and infrared stealth functions and a preparation method of the coating, and the coating comprises the following raw materials in parts by weight: 4.9-5.0 parts of low-emissivity filler, 18.3-18.5 parts of toning resin and 1.4-1.6 parts of curing agent. Wherein the low-emissivity filler adopts sheet-shaped aluminum powder or sheet-shaped silver powder with the particle size of 20 [mu] m-50 [mu] m; the toning resin is composed of BC05 resin, an inorganic black pigment, an inorganic blue pigment and an inorganic yellow pigment in a weight ratio of (30-32): (14.8-15.2): (2.9-3.1): (0.9-1.1). The coating provided by the invention has airplane gray and infrared stealth dual performances, has good adhesive force, is mainly formed by an air spraying technology and a low-temperature curing technology during preparation, is simple to operate and is convenient for industrial large-scale production.

Description

Technical Field

[0001] The invention belongs to the technical field of functional materials, and in particular relates to a coating having both aircraft gray color and infrared stealth and a preparation method thereof. Background Art

[0002] As we all know, infrared technology is widely used in many fields. Infrared detection plays a key role in target detection, identification, aiming and even guidance with its outstanding characteristics such as all-weather, concealment and passive detection. Corresponding infrared stealth technology came into being. Its core is to minimize the difference in infrared radiation between the equipment itself and the background, that is, to reduce the infrared radiation energy emitted by the equipment, thereby reducing the possibility of the equipment being detected and identified. Among the many means of achieving infrared stealth, infrared stealth materials have significant advantages. They can easily give equipment infrared stealth function without changing the original structure of the equipment, thereby improving the safety of the equipment.

[0003] In actual application scenarios, such as aircraft exterior coatings, there is a thorny problem. Aircraft gray (590 gray) is a commonly used exterior color. The fillers used in traditional color matching are typically ferroferric oxide. From the perspective of chemical structure characteristics, it shows a strong absorption rate in the infrared band, which leads to the infrared emissivity of the surface of the aircraft gray coating containing such fillers, which is usually in the higher range of 0.5 to 0.8. If you want to enhance the infrared stealth capability of the coating, the conventional idea is to add low-emissivity fillers, but the existing fillers are mostly made of metal or alloy particles. Once made into a coating, the appearance is often bright silver or dark silver, which is very different from the gray required for the aircraft. Therefore, how to ensure low emissivity to achieve infrared stealth effect while keeping the color of the coating and the gray of the aircraft small has become a technical difficulty that needs to be overcome.

[0004] In addition, from the perspective of industrial production and practical operation convenience, the coating is not only required to have excellent stealth and appearance adaptability, but its preparation process is also crucial. The ideal preparation process should have low equipment requirements, simple operation, easy control, and be able to adapt to the rhythm of large-scale industrial production, so as to meet the market demand for such functional coatings.

[0005] In view of this, this invention is proposed. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a coating with both aircraft gray and infrared stealth and a preparation method thereof, which are mainly used to solve the problem that the color difference of aircraft gray is inconsistent with the infrared stealth performance. In addition, the preparation method provided by the present invention obtains a coating with both aircraft gray and infrared stealth performance and good adhesion performance. At the same time, the preparation method mainly uses air spraying technology and low-temperature curing technology, which is simple to operate and easy to realize industrial-scale production.

[0007] The purpose of the present invention is to be solved by the following technical solutions:

[0008] In a first aspect, the present invention provides a coating having both aircraft gray color and infrared stealth, comprising the following raw materials in parts by weight: 4.9 to 5.0 parts of a low-emissivity filler, 18.3 to 18.5 parts of a toning resin, and 1.4 to 1.6 parts of a curing agent;

[0009] Among them, the color-adjusting resin is composed of BC05 resin, inorganic black pigment, inorganic blue pigment and inorganic yellow pigment, and the weight ratio of the BC05 resin, inorganic black pigment, inorganic blue pigment and inorganic yellow pigment is (30-32): (14.8-15.2): (2.9-3.1): (0.9-1.1).

[0010] Furthermore, the low emissivity filler is flaky aluminum powder or flaky silver powder, and the particle size range of the flaky aluminum powder or flaky silver powder is 20 μm to 50 μm.

[0011] Furthermore, the inorganic black pigment is titanium black or ferrosoferric oxide with a particle size less than or equal to 1.5 μm, the inorganic blue pigment is cobalt blue with a particle size less than or equal to 1.5 μm, and the inorganic yellow pigment is zinc iron yellow with a particle size less than or equal to 1.5 μm.

[0012] Furthermore, the curing agent is a polyamide curing agent.

[0013] Preferably, the polyamide curing agent is 650 curing agent or 200 low molecular weight polyamide.

[0014] In a second aspect, the present invention provides a method for preparing the above-mentioned coating having both aircraft gray color and infrared stealth, which specifically comprises the following steps:

[0015] Step 1, substrate pretreatment: cleaning the surface of the substrate to remove impurities on the surface of the substrate;

[0016] Step 2, preparing the coating: first, according to weight parts, 4.9-5.0 parts of low-emissivity filler, 18.3-18.5 parts of toning resin and 1.4-1.6 parts of curing agent are weighed as raw materials, and then the raw materials are mixed and dispersed in a homogenizer, the speed of the homogenizer is set to 1500r / min-2000r / min, the dispersion time is set to 4min-6min, and xylene diluent is added during the dispersion process, so that the viscosity of the dispersed coating is controlled within the range of 54s-58s (coating-4 cups);

[0017] Step 3, preparing the coating: spraying the coating prepared in step 2 onto the substrate treated in step 1 by air spraying technology, wherein the parameters during the spraying are set as follows: air pressure of 0.4MPa-0.6MPa, spraying distance of 15cm-25cm, spray gun moving speed of 20cm / s-40cm / s, and spraying times of 2-4 times; finally, after curing treatment, the coating having both aircraft gray color and infrared stealth is obtained.

[0018] It should be noted that there is no particular order between step 1 and step 2 in the present invention, and both can be performed simultaneously.

[0019] Among them, in step 1 of the present invention, when cleaning the surface of the substrate, the following two specific operation methods can be adopted: one is to wipe the surface of the substrate with a non-woven fabric soaked with anhydrous ethanol to remove impurities by physical wiping; the other is to use a spray gun to spray anhydrous ethanol dilution onto the surface of the substrate to remove impurities by liquid flushing and the like. The above two methods can clean the surface of the substrate based on anhydrous ethanol, lay a good foundation for the subsequent coating preparation, ensure that the surface of the substrate is clean, and thus facilitate better adhesion of the coating.

[0020] It should be noted that in step 2 of the present invention, the low emissivity filler is flaky aluminum powder or flaky silver powder, and the particle size of the flaky particles selected for both are 20 μm to 50 μm. The reasons are mainly the following two points: First, the flaky aluminum powder or flaky silver powder has a smooth surface and has a strong reflective ability for infrared rays. When infrared rays are projected onto its surface, most of the energy will be directly reflected. In addition, due to its special flaky structure, the infrared rays will be reflected multiple times on the surface of the flaky particles. Each reflection can return part of the energy. When the flaky particles are accumulated to form a coating, this characteristic of multiple and efficient infrared reflection becomes more and more significant, greatly It reduces the amount of infrared absorption, which is beneficial to infrared stealth; secondly, from the perspective of structural characteristics, the flaky particles have a larger extension size in the planar direction but are relatively short in the vertical direction, which hinders the propagation of infrared rays in the flaky plane. Once stacked into a coating, the limiting effect is more prominent, which can effectively block the penetration of infrared rays. In addition, during the spraying process, the mist droplets carry the flaky particles and hit the surface of the substrate at high speed. Thanks to the flaky structure, the particles are easily spread and stretched on the plane under the synergistic effect of gravity and surface tension, and then stacked in an orderly manner into a flat coating structure, which not only ensures the regularity of the physical form of the coating, but also enhances the infrared stealth effect.

[0021] In addition, in step 2 of the present invention, the color-adjusting resin is composed of BC05 resin, inorganic black pigment, inorganic blue pigment and inorganic yellow pigment, and the weight ratio of the BC05 resin, inorganic black pigment, inorganic blue pigment and inorganic yellow pigment is (30-32): (14.8-15.2): (2.9-3.1): (0.9-1.1). Among them, BC05 resin has a high solid content of 89% to 91%. This feature ensures that the resin has sufficient effective substances to participate in building a stable structure during the film-forming process, providing internal support for the tough performance of the subsequent coating. When BC05 resin is coated on the surface of a rough substrate, it can penetrate into the tiny pores and depressions on the surface of the substrate by virtue of its own fluidity, and construct a "pinning and inlaying" effect, so that the coating and the substrate are closely dependent on each other, greatly enhancing the adhesion of the coating, thereby avoiding peeling, peeling and other undesirable conditions; the inorganic black pigment is titanium black or ferrosoferric oxide with a particle size less than or equal to 1.5μm, the inorganic blue pigment is cobalt blue with a particle size less than or equal to 1.5μm, and the inorganic yellow pigment is zinc iron yellow with a particle size less than or equal to 1.5μm. These tiny inorganic pigments (black, blue, and yellow) can be evenly suspended in the resin after high-speed dispersion operation. At the same time, given that the low-emissivity filler is in the form of flake particles, when the spraying process is completed and spread out, the flake filler and the resin fit each other: on the one hand, the flake filler supports a solid internal framework for the coating, giving it basic strength; on the other hand, the uniformly suspended inorganic pigment particles are just right to fill the gap between the resin and the flake filler, making the entire coating more dense and compact. The synergy of the two, plus the curing agent, can comprehensively improve the strength of the coating itself, making it more impact-resistant and wear-resistant, and achieving a color difference of no more than 2 between the coating and the 590 gray standard color card, ensuring the appearance consistency of the coating and the outer surface of the aircraft gray equipment.

[0022] In addition, in step 2 of the present invention, the viscosity of the coating is controlled within the range of 54s to 58s. This is because when the coating viscosity is too high, it is easy to cause spray atomization difficulty, large droplets, and then form problems such as sagging, excessive thickness, and slow drying speed; and when the coating viscosity is too low, it is easy to cause the solid content of the coating to decrease, so that the coating hiding property becomes poor. In addition, when the low-viscosity coating is sprayed, it is also prone to sagging problems due to its strong fluidity, and the solvent evaporates quickly, and the solvent evaporates quickly in large quantities to take away heat, so that the surface temperature of the coating is reduced, which inhibits the subsequent drying process. Therefore, it is necessary to use a diluent to adjust the coating viscosity so that it is within a reasonable range.

[0023] In step 3 of the present invention, the specific process of the curing treatment is as follows: first, air-dry the substrate sprayed with the coating at room temperature for at least 30 minutes to give the coating a preliminary setting, so that the solvent in the coating can evaporate slowly, and avoid problems such as surface cracking and poor leveling caused by too fast drying; then put it into the drying equipment, and heat it from room temperature to 75°C~85°C for 25min~35min, and keep it warm for 230min~250min. It is completely different from the traditional high-temperature curing process. The present invention uses low-temperature curing technology. Its core principle is to achieve the curing of the coating with the help of addition polymerization reaction. The curing temperature required by this technology is only 85°C at most, which can significantly reduce energy consumption, and can significantly reduce defects such as bubbles and pores caused by too fast volatilization of the diluent, making the coating denser and more bonding. Performance is stronger; finally, it is cooled to room temperature with the drying equipment, avoiding the internal stress problem that may be caused by sudden cooling, further ensuring the stability and reliability of the coating, and comprehensively ensuring that the final prepared coating has both aircraft gray and infrared stealth, and has excellent comprehensive performance.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] First, from the perspective of material selection and proportion, the present invention selects a specific weight of low-emissivity filler, a color-adjusting resin and a curing agent for compounding and curing, so that the coating meets the requirements of color difference while meeting the requirements of low emissivity. Among them, the low-emissivity filler is selected from flaky aluminum powder or flaky silver powder with a particle size of 20μm to 50μm, and the color-adjusting resin is formed by combining BC05 resin, inorganic black pigment, inorganic blue pigment and inorganic yellow pigment in a set weight ratio. In this way, the problem of the contradiction between the gray color difference of the aircraft and the infrared stealth performance is successfully overcome, and the coating can maintain a very small color difference with the gray of the aircraft, and the color difference is less than 2 after actual testing according to GB / T 11186.3-1989; and it has excellent infrared stealth ability. According to GJB 5023.2-2003, the surface infrared emissivity of the coating at room temperature is less than 0.35 in the 8μm to 14μm band after actual testing, which fully meets the dual requirements of the aircraft appearance for color and stealth function. At the same time, after actual testing according to GB / T 1720-1989, the coating adhesion reached level 2, indicating that the adhesion was firm and reliable, thus increasing the service life of the coating.

[0026] Second, from the perspective of preparation process, the present invention mainly adopts air spraying technology and low-temperature curing technology when preparing the coating. Among them, air spraying can form a uniform film, making the prepared coating delicate and smooth. Even the hidden corners of parts, such as gaps and bumps, can be accurately sprayed in place. In addition, the equipment is simple, the control parameters are streamlined, the environmental adaptability is strong, the operation is convenient, and it is easy to realize industrialization; low-temperature curing relies on addition polymerization reaction, and the maximum curing temperature is only 85°C. Compared with the traditional high-temperature curing of about 250°C, energy consumption is greatly reduced. At the same time, it can effectively avoid the drawbacks of bubbles and pores derived from the rapid volatilization of diluents, making the coating dense and more bonded. The process is simple and controllable, which is conducive to industrial production and application.

[0027] In summary, the coating and preparation method thereof provided by the present invention have achieved major breakthroughs in both material selection and ratio as well as optimization of the preparation process, and have successfully solved the problem of balancing the gray color difference and infrared stealth performance of aircraft, providing a highly competitive solution to the demand for high-performance stealth coatings in the aerospace and other fields, and having broad market prospects and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings are incorporated in and constitute a part of this specification and, together with the description, serve to explain the principles of the present invention.

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 It is a flow chart of the coating preparation method of the present invention. DETAILED DESCRIPTION

[0031] Here, exemplary embodiments will be described in detail. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are only examples consistent with some aspects of the present invention as detailed in the appended claims.

[0032] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0033] The invention provides a coating having both aircraft gray color and infrared stealth, comprising the following raw materials in parts by weight: 4.9 to 5.0 parts of a low-emissivity filler, 18.3 to 18.5 parts of a toning resin and 1.4 to 1.6 parts of a curing agent.

[0034] Specifically, the low emissivity filler in the present invention is flaky aluminum powder or flaky silver powder, and the particle size of the flaky aluminum powder or the flaky silver powder is in the range of 20 μm to 50 μm.

[0035] The coloring resin in the present invention is composed of BC05 resin, inorganic black pigment, inorganic blue pigment and inorganic yellow pigment, and the weight ratio of BC05 resin, inorganic black pigment, inorganic blue pigment and inorganic yellow pigment is (30-32): (14.8-15.2): (2.9-3.1): (0.9-1.1). Among them, the inorganic black pigment is titanium black or ferrosoferric oxide with a particle size less than or equal to 1.5 μm, the inorganic blue pigment is cobalt blue with a particle size less than or equal to 1.5 μm, and the inorganic yellow pigment is zinc iron yellow with a particle size less than or equal to 1.5 μm.

[0036] The curing agent in the present invention is a polyamide curing agent, and the polyamide curing agent is a 650 curing agent or a 200 low molecular weight polyamide.

[0037] like Figure 1 As shown, the present invention also provides a method for preparing the above coating, which specifically comprises the following steps:

[0038] Step 1: Substrate pretreatment: Use anhydrous ethanol to clean the surface of the substrate to remove impurities and lay a good foundation for subsequent coating adhesion;

[0039] Step 2, preparing the coating: first, according to weight parts, 4.9-5.0 parts of low emissivity filler, 18.3-18.5 parts of toning resin and 1.4-1.6 parts of curing agent are weighed as raw materials, and then the raw materials are mixed and dispersed with a homogenizer at a speed of 1500r / min-2000r / min for 4min-6min, and a diluent is added at the same time to control the viscosity of the coating at 54s-58s to ensure good coating construction performance and avoid problems such as poor atomization and sagging due to excessively high or low viscosity;

[0040] Step 3, preparing the coating: using air spraying technology, spray the coating prepared in step 2 onto the substrate treated in step 1, and the specific spraying parameters are set as follows: air pressure of 0.4MPa-0.6MPa, spraying distance of 15cm-25cm, spray gun moving speed of 20cm / s-40cm / s, spraying times of 2-4 times, so that the coating evenly covers the substrate; after curing treatment, first air-dry the substrate sprayed with the coating at room temperature for at least 30min, then put it into a drying device, and heat it from room temperature to 75°C-85°C for 25min-35min, keep it warm for 230min-250min, and finally cool it to room temperature with the drying device. The low-temperature curing technology is realized by addition polymerization reaction, has low energy consumption, can also reduce bubbles and pores, and make the coating dense and strongly bonded.

[0041] In order to further verify the efficacy of the powder metallurgy method of the present invention, the inventors conducted the following specific experiments:

[0042] Example 1

[0043] An embodiment of the present invention provides a coating A having both aircraft gray color and infrared stealth, comprising the following raw materials in parts by weight: 4.9 parts of a low-emissivity filler, 18.3 parts of a color-adjusting resin, and 1.4 parts of a curing agent.

[0044] Among them, the low-emissivity filler is flaky aluminum powder with a particle size of 20μm to 40μm; the color-adjusting resin is composed of BC05 resin, titanium black, cobalt blue and zinc iron yellow, and the weight ratio of BC05 resin, titanium black, cobalt blue and zinc iron yellow is 30:14.8:2.9:0.9, and the particle sizes of titanium black, cobalt blue and zinc iron yellow are all less than or equal to 1.5μm; the curing agent is 650 curing agent.

[0045] The preparation process of a coating A having both aircraft gray color and infrared stealth in this embodiment is as follows:

[0046] 1) Substrate pretreatment: The titanium alloy substrate is cleaned with a non-woven fabric soaked in anhydrous ethanol to remove impurities on the surface of the titanium alloy substrate;

[0047] 2) Preparation of coating: First, 4.9 parts of flaky aluminum powder, 18.3 parts of toning resin (including BC05 resin, titanium black, cobalt blue and zinc yellow in a weight ratio of 30:14.8:2.9:0.9) and 1.4 parts of 650 curing agent are weighed as raw materials according to weight; then all the raw materials are mixed and dispersed in a homogenizer, the speed of the homogenizer is set to 1750r / min, the dispersion time is set to 5min, and xylene diluent is added during the dispersion process, so that the viscosity of the dispersed coating is 56s (coating-4 cups);

[0048] 3) The coating prepared in step 2) is sprayed onto the titanium alloy substrate treated in step 1) by air spraying technology, and the parameters during spraying are set as follows: air pressure of 0.5 MPa, spraying distance of 20 cm, spray gun moving speed of 30 cm / s, and spraying times of 3 times; then a curing treatment is performed, during which the titanium alloy substrate sprayed with the coating is first air-dried for 40 minutes at room temperature, then placed in an oven, and heated from room temperature to 80°C over 30 minutes, kept warm for 240 minutes, and finally cooled to room temperature in the oven to obtain a coating A having both aircraft gray and infrared stealth.

[0049] Example 2

[0050] The embodiment of the present invention provides a coating B having both aircraft gray color and infrared stealth, comprising the following raw materials in parts by weight: 4.95 parts of a low-emissivity filler, 18.4 parts of a toning resin, and 1.5 parts of a curing agent.

[0051] Among them, the low-emissivity filler is flaky silver powder with a particle size of 30μm to 50μm; the color-adjusting resin is composed of BC05 resin, ferroferric oxide, cobalt blue and zinc iron yellow, and the weight ratio of BC05 resin, titanium black, cobalt blue and zinc iron yellow is 31:15:3:1, and the particle sizes of ferroferric oxide, cobalt blue and zinc iron yellow are all less than or equal to 1.5μm; the curing agent is 200 low-molecular polyamide.

[0052] The preparation process of a coating B having both aircraft gray color and infrared stealth in this embodiment is as follows:

[0053] 1) Substrate pretreatment: cleaning the alumina ceramic substrate with anhydrous ethanol using a spray gun to remove impurities on the surface of the alumina ceramic substrate;

[0054] 2) Prepare the coating: first, weigh 4.95 parts of flaky silver powder, 18.4 parts of toning resin (including BC05 resin, ferroferric oxide, cobalt blue and zinc yellow in a weight ratio of 31:15:3:1) and 1.5 parts of 200 low molecular weight polyamide as raw materials according to weight parts; then mix all the raw materials and disperse them in a homogenizer. The speed of the homogenizer is set to 1500r / min, the dispersion time is set to 6min, and xylene diluent is added during the dispersion process to make the viscosity of the dispersed coating 54s (coating-4 cups);

[0055] 3) The coating prepared in step 2) is sprayed onto the alumina ceramic substrate treated in step 1) by air spraying technology, and the parameters during spraying are set as follows: air pressure of 0.6 MPa, spraying distance of 15 cm, spray gun moving speed of 40 cm / s, and spraying times of 4 times; followed by curing treatment, during the curing treatment, the alumina ceramic substrate sprayed with the coating is first air-dried for 35 minutes at room temperature, then placed in an oven, and heated from room temperature to 75°C over 25 minutes, kept warm for 250 minutes, and finally cooled to room temperature with the oven, thereby obtaining a coating B having both aircraft gray and infrared stealth.

[0056] Example 3

[0057] An embodiment of the present invention provides a coating C having both aircraft gray color and infrared stealth, comprising the following raw materials in parts by weight: 5 parts of a low-emissivity filler, 18.5 parts of a color-adjusting resin, and 1.6 parts of a curing agent.

[0058] Among them, the low-emissivity filler is flaky aluminum powder with a particle size of 20μm to 50μm; the color-adjusting resin is composed of BC05 resin, titanium black, cobalt blue and zinc iron yellow, and the weight ratio of BC05 resin, titanium black, cobalt blue and zinc iron yellow is 32:15.2:3.1:1.1, and the particle sizes of titanium black, cobalt blue and zinc iron yellow are all less than or equal to 1.5μm; the curing agent is 200 low molecular weight polyamide.

[0059] The preparation process of a coating C having both aircraft gray color and infrared stealth in this embodiment is as follows:

[0060] 1) Substrate pretreatment: The aluminum alloy substrate is cleaned with anhydrous ethanol using a spray gun to remove impurities on the surface of the aluminum alloy substrate;

[0061] 2) Preparation of coating: First, 5 parts of flaky silver powder, 18.5 parts of toning resin (including BC05 resin, titanium black, cobalt blue and zinc yellow in a weight ratio of 32:15.2:3.1:1.1) and 1.6 parts of 200 low molecular weight polyamide are weighed as raw materials according to weight; then all the raw materials are mixed and dispersed in a homogenizer, the speed of the homogenizer is set to 2000r / min, the dispersion time is set to 4min, and xylene diluent is added during the dispersion process, so that the viscosity of the dispersed coating is 58s (coating-4 cups);

[0062] 3) The coating prepared in step 2) is sprayed onto the aluminum alloy substrate treated in step 1) by air spraying technology, and the parameters during spraying are set as follows: air pressure of 0.4 MPa, spraying distance of 25 cm, spray gun moving speed of 20 cm / s, and spraying times of 2 times; then a curing treatment is performed, during the curing treatment, the aluminum alloy substrate sprayed with the coating is first air-dried for 30 minutes at room temperature, then placed in an oven, and heated from room temperature to 85°C over 35 minutes, kept warm for 230 minutes, and finally cooled to room temperature with the oven, thereby obtaining a coating C having both aircraft gray and infrared stealth.

[0063] In order to further illustrate the effect of the coating preparation method of the present invention, the inventors conducted the following relevant performance tests on the coating A, coating B and coating C obtained in Examples 1 to 3 respectively: the adhesion performance of the prepared coatings was tested using a paint film circle tester according to GB / T 1720-1989; the infrared emissivity of the prepared coatings was tested at room temperature in the 8μm to 14μm band using a handheld infrared emissivity meter according to GJB 5023.2-2003; the color difference performance of the prepared coatings was tested using a colorimeter according to GB / T 11186.3-1989, and the test results are shown in Table 1 below.

[0064] Table 1 Test results of relevant properties of coatings prepared in Examples 1 to 3

[0065] project Coating A Coating B Coating C Adhesion Level 2 Level 2 Level 2 Infrared emissivity 0.33、0.33、0.34 0.32、0.34、0.33 0.34、0.32、0.34 Color difference (590 gray) 1.01、1.03、1.04 1.02、1.05、1.03 1.03、1.03、1.02

[0066] The test results in Table 1 show that the coating prepared by the present invention has excellent adhesion performance, infrared stealth performance and color difference performance. Among them, the adhesion performance reaches level 2, ensuring the stable adhesion of the coating; the infrared emissivity is less than 0.35, which effectively guarantees the infrared stealth effect; the color difference with the aircraft (590 gray) standard color card is less than 2, accurately matching the gray appearance of the aircraft. The coating fully meets the dual requirements of low emissivity to achieve infrared stealth and small color difference with the gray of the aircraft, which helps to improve the stealth effect of various equipment.

[0067] The above description is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0068] It should be understood that the present invention is not limited to what has been described above and that various modifications and changes may be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A coating having both aircraft gray color and infrared stealth, characterized in that: The invention comprises the following raw materials in parts by weight: 4.9 to 5.0 parts of a low-emissivity filler, 18.3 to 18.5 parts of a toning resin and 1.4 to 1.6 parts of a curing agent; Among them, the color-adjusting resin is composed of BC05 resin, inorganic black pigment, inorganic blue pigment and inorganic yellow pigment, and the weight ratio of the BC05 resin, inorganic black pigment, inorganic blue pigment and inorganic yellow pigment is (30-32): (14.8-15.2): (2.9-3.1): (0.9-1.1).

2. The coating having both aircraft gray color and infrared stealth according to claim 1, characterized in that: The low emissivity filler is flaky aluminum powder or flaky silver powder, and the particle size of the flaky aluminum powder or flaky silver powder is in the range of 20 μm to 50 μm.

3. The coating having both aircraft gray color and infrared stealth according to claim 1, characterized in that: The inorganic black pigment is titanium black or ferrosoferric oxide with a particle size less than or equal to 1.5 μm, the inorganic blue pigment is cobalt blue with a particle size less than or equal to 1.5 μm, and the inorganic yellow pigment is zinc iron yellow with a particle size less than or equal to 1.5 μm.

4. The coating having both aircraft gray color and infrared stealth according to claim 1, characterized in that: The curing agent is a polyamide curing agent.

5. A method for preparing a coating having both aircraft gray color and infrared stealth according to any one of claims 1 to 4, characterized in that: The specific steps include: Step 1, substrate pretreatment: cleaning the surface of the substrate to remove impurities on the surface of the substrate; Step 2, preparing the coating: first, according to weight parts, 4.9-5.0 parts of low emissivity filler, 18.3-18.5 parts of toning resin and 1.4-1.6 parts of curing agent are weighed as raw materials, and then the raw materials are mixed and dispersed, and a diluent is added during the dispersion process to control the viscosity of the coating after dispersion within a set range; Step 3, preparing a coating: spraying the coating prepared in step 2 onto the substrate treated in step 1, and obtaining the coating having both aircraft gray color and infrared stealth after curing.

6. The method for preparing the coating having both aircraft gray color and infrared stealth according to claim 5, characterized in that: In step 1, anhydrous ethanol is used to clean the surface of the substrate.

7. The method for preparing the coating having both aircraft gray color and infrared stealth according to claim 5, characterized in that: In step 2, a homogenizer is used to disperse the raw materials, and the rotation speed of the homogenizer is set to 1500r / min to 2000r / min, and the dispersion time is set to 4min to 6min.

8. The method for preparing the coating having both aircraft gray color and infrared stealth according to claim 5, characterized in that: In step 2, the viscosity of the coating is set in the range of 54s to 58s.

9. The method for preparing the coating having both aircraft gray color and infrared stealth according to claim 5, characterized in that: In step 3, air spraying technology is used for spraying, and the parameters are set as follows: air pressure is 0.4MPa-0.6MPa, spraying distance is 15cm-25cm, spray gun moving speed is 20cm / s-40cm / s, and spraying times is 2-4 times.

10. The method for preparing the coating having both aircraft gray color and infrared stealth according to claim 5, characterized in that: In step 3, the specific process of the curing treatment is as follows: first, air-dry the substrate sprayed with the coating at room temperature for at least 30 minutes; then put it into a drying device, and heat it from room temperature to 75°C to 85°C over 25min to 35min, and keep it warm for 230min to 250min; finally, cool it to room temperature with the drying device.

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