Infrared suppression thermal control coating of spacecraft heat radiator and preparation method of infrared suppression thermal control coating

Abstract

The invention relates to the technical field of thermal control of spacecrafts, and particularly provides an infrared suppression thermal control coating of a spacecraft heat radiator and a preparation method of the infrared suppression thermal control coating. A silver reflecting layer with the thickness of 100 nm to 400 nm, an aluminum oxide oxidation inhibition layer with the thickness of 50 nm to 200 nm, a silicon oxide emissivity regulation and control layer with the thickness of 100 nm to 400 nm and an indium tin oxide (ITO) layer with the thickness of 40 nm to 80 nm are sequentially deposited on the surface of a rigid or flexible base material. Absorption of infrared band energy is reduced, the influence of environment infrared heat radiation on thermal control is effectively restrained, the adverse effect of self heat radiation on infrared optical detection is reduced, the excellent infrared restraining capacity is achieved, the anti-static function is achieved, and under the environment effects of damp heat, heat circulation, ultraviolet radiation, particle radiation and the like, the thermal control effect is improved. Good space environment resistance stability is achieved, and the infrared suppression material can be widely applied to infrared suppression in the radiation heat dissipation process of spacecrafts.

Description

Technical Field

[0001] The invention relates to the technical field of surface engineering, and in particular to an infrared suppression thermal control coating for a spacecraft thermal radiator and a preparation method thereof. Background Art

[0002] In the space environment, the spacecraft is in a vacuum environment and cannot dissipate heat by convection. Therefore, radiation heat dissipation is the only way to release the heat of the spacecraft. Emissivity is a key parameter that characterizes heat dissipation capacity. The higher the emissivity, the stronger the heat dissipation capacity. When the spacecraft is exposed to sunlight, it will also absorb sunlight energy. Therefore, a low solar absorptivity is also a key parameter that affects the thermal control performance of the coating. Commonly used spacecraft thermal control coatings generally have low solar absorptivity and high emissivity, and have high energy absorption in the infrared band. In a strong infrared radiation environment, the heat dissipation efficiency will be affected due to the absorption of infrared energy. In addition, the infrared waves radiated during the heat dissipation process of the thermal control coating will affect the performance of infrared optical detection devices.

[0003] Therefore, it has become an urgent problem to develop a thermal control coating with low solar absorptivity and emissivity, infrared suppression capability, and good stability under space environments such as humidity, thermal cycles, ultraviolet radiation, and particle radiation. Summary of the invention

[0004] In view of the deficiencies in the prior art, an object of the present invention is to provide an infrared suppression thermal control coating for a spacecraft thermal radiator and a preparation method thereof.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides an infrared suppression thermal control coating for a spacecraft thermal radiator, comprising a substrate, and a reflective layer, an oxidation suppression layer, an emissivity regulation layer and an indium tin oxide (ITO) layer sequentially arranged on the surface of the substrate, wherein the reflective layer is relatively close to the substrate, and the ITO layer is relatively far away from the substrate.

[0007] Furthermore, the substrate is a rigid or flexible substrate.

[0008] Furthermore, the material of the substrate is aluminum alloy, titanium alloy, carbon fiber composite material or polyimide film.

[0009] Furthermore, the reflective layer is a silver reflective layer, which is prepared by a DC magnetron sputtering method.

[0010] Furthermore, the thickness of the silver reflective layer is 100-400 nm.

[0011] Furthermore, the oxidation inhibition layer is an aluminum oxide layer, which is prepared by reactive magnetron sputtering.

[0012] Furthermore, the thickness of the aluminum oxide layer is 50-200 nm.

[0013] Furthermore, the emissivity regulating layer is a silicon oxide layer, which is prepared by reactive magnetron sputtering.

[0014] Furthermore, the thickness of the silicon oxide coating is 100-400 nm.

[0015] Furthermore, the indium tin oxide (ITO) layer is prepared by direct current magnetron sputtering.

[0016] Furthermore, the thickness of the indium tin oxide (ITO) layer is 40-80 nm.

[0017] In a second aspect, the present invention provides a method for preparing an infrared suppression thermal control coating of a spacecraft thermal radiator, comprising the following steps:

[0018] Step (1) providing a substrate, which is pre-treated and ready for use;

[0019] Step (2) placing the substrate in a reaction chamber of a magnetron sputtering device, and evacuating the reaction chamber to a vacuum of 2×10 -3 below pa;

[0020] Step (3) introducing argon gas into the reaction chamber of the magnetron sputtering device to perform DC magnetron sputtering deposition to form a silver reflective layer on the surface of the substrate;

[0021] Step (4) introducing a mixed gas of argon and oxygen into the reaction chamber of the magnetron sputtering device to perform reactive magnetron sputtering deposition to form an aluminum oxide layer on the surface of the silver reflective layer;

[0022] Step (5) introducing a mixed gas of argon and oxygen into the reaction chamber of the magnetron sputtering device to perform reactive magnetron sputtering deposition to form a silicon oxide layer on the surface of the aluminum oxide layer;

[0023] Step (6) introduces a mixed gas of argon and oxygen into the reaction chamber of the magnetron sputtering equipment to perform DC magnetron sputtering deposition to form an indium tin oxide (ITO) layer on the surface of the silicon oxide layer to obtain an infrared suppression thermal control coating for the spacecraft thermal radiator.

[0024] Furthermore, in the step (3), the conditions for DC magnetron sputtering deposition are: using a silver target, an argon gas flow rate of 200 to 1000 sccm, a deposition pressure of 0.2 to 0.8 Pa, a deposition power of 400 to 2000 W, and stopping the deposition when the thickness of the silver reflective layer reaches 100 to 400 nm.

[0025] Furthermore, in the step (4), the conditions for reactive magnetron sputtering deposition are: using an aluminum target, an argon flow rate of 200 to 1000 sccm, an oxygen flow rate of 100 to 600 sccm, a deposition pressure of 0.2 to 0.8 Pa, a deposition power of 400 to 2000 W, and stopping the deposition when the thickness of the aluminum oxide layer reaches 50 to 200 nm.

[0026] Furthermore, in the step (5), the conditions for reactive magnetron sputtering deposition are: using a silicon target, an argon flow rate of 200 to 800 sccm, an oxygen flow rate of 200 to 600 sccm, a deposition pressure of 0.2 to 0.8 Pa, a deposition power of 400 to 2000 W, and stopping the deposition when the thickness of the silicon oxide coating reaches 100 to 400 nm.

[0027] Furthermore, in the step (6), the conditions for DC magnetron sputtering deposition are: using an indium tin oxide ceramic target, an argon flow rate of 50 to 600 sccm, an oxygen flow rate of 5 to 100 sccm, a deposition pressure of 0.2 to 0.8 Pa, and a deposition power of 200 to 1000 W. When the thickness of the indium tin oxide (ITO) layer reaches 40 to 80 nm, the deposition is stopped.

[0028] The technical solution of the present invention has the following advantages:

[0029] 1. The infrared suppression thermal control coating of the spacecraft thermal radiator provided by the present invention absorbs less energy in the infrared band, can effectively suppress the influence of environmental infrared thermal radiation on thermal control, and reduce the adverse effect of its own thermal radiation on infrared optical detection.

[0030] 2. The infrared suppression thermal control coating of the spacecraft thermal radiator provided by the present invention has low absorption for electromagnetic waves of 0.3 μm to 25 μm, the solar absorptivity and emissivity are both lower than 0.1, and the absorption-emission ratio is maintained at 0.8 to 1.2.

[0031] 3. The infrared suppression thermal control coating for the spacecraft thermal radiator provided by the present invention not only has excellent infrared suppression capability, but also has anti-static function. It exhibits good stability against space environment under the influence of humidity, heat, thermal cycle, ultraviolet radiation, particle radiation and other environmental conditions, and can be widely used in infrared suppression during the radiation heat dissipation process of spacecraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 It is a schematic diagram of the structure of an infrared suppression thermal control coating for a spacecraft thermal radiator provided by an embodiment of the present invention.

[0034] Figure 2 It is a schematic diagram of the process flow of a method for preparing an infrared suppression thermal control coating for a spacecraft thermal radiator provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0035] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0036] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the art can be used. The raw materials or instruments used are all conventional products that can be obtained commercially, including but not limited to the raw materials or instruments used in the examples of this application.

[0037] The following will be combined with the attached Figure 1 and attached Figure 2 , an infrared suppression thermal control coating for a spacecraft thermal radiator and a preparation method thereof provided in an embodiment of the present invention are introduced in detail.

[0038] The technical problem to be solved by the present invention is to overcome the problem that the thermal control coating in the prior art has a high absorption of energy in the infrared band, absorbs infrared energy in a strong infrared radiation environment and affects the heat dissipation efficiency, and the infrared waves radiated during the heat dissipation of the thermal control coating will affect the performance of infrared optical detection devices, and cannot meet the actual thermal control requirements of the spacecraft. To this end, an infrared suppression thermal control coating for a spacecraft thermal radiator and a preparation method thereof are proposed. The basic principle is to deposit a composite coating comprising a reflective layer, an oxidation suppression layer, an emissivity control layer and an indium tin oxide (ITO) layer on the surface of a substrate to reduce the absorption of energy in the infrared band, effectively suppress the influence of environmental infrared thermal radiation on thermal control, and reduce the adverse effect of self-thermal radiation on infrared optical detection; at the same time, reduce the absorption of 0.3μm to 25μm electromagnetic waves, reduce the solar absorptivity and emissivity to below 0.1, and maintain the absorption-emission ratio at 0.8 to 1.2.

[0039] The infrared suppression thermal control coating for the spacecraft thermal radiator provided by the present invention not only has excellent infrared suppression capability, but also has anti-static function. It exhibits good stability against space environment under the influence of humidity, heat, thermal cycle, ultraviolet radiation, particle radiation and other environmental conditions, and can be widely used in infrared suppression during radiation heat dissipation of spacecraft.

[0040] Reference Figure 1 The embodiment of the present invention provides an infrared suppression thermal control coating for a spacecraft thermal radiator, the structure of which is as follows: Figure 1 As shown, it includes: a substrate, and a reflective layer, an oxidation inhibition layer, an emissivity control layer and an indium tin oxide (ITO) layer arranged in sequence on the surface of the substrate, wherein the reflective layer is relatively close to the substrate, the ITO layer is relatively far away from the substrate, the reflective layer is a silver reflective layer, the oxidation inhibition layer is an aluminum oxide layer, and the emissivity control layer is a silicon oxide layer.

[0041] Furthermore, the substrate is a rigid or flexible substrate, and the material of the substrate is aluminum alloy, titanium alloy, carbon fiber composite material or polyimide film; the thickness of the silver reflective layer is 100-400nm, the thickness of the aluminum oxide layer is 50-200nm, the thickness of the silicon oxide coating is 100-400nm, and the thickness of the indium tin oxide (ITO) layer is 40-80nm; the silver reflective layer and the indium tin oxide (ITO) layer are prepared by DC magnetron sputtering deposition, and the aluminum oxide layer and the silicon oxide layer are prepared by reactive magnetron sputtering deposition.

[0042] Reference Figure 2 The present invention provides a method for preparing an infrared suppression thermal control coating for a spacecraft thermal radiator, and the process flow is as follows: Figure 2 As shown, the following steps are included:

[0043] Step (1) providing a substrate, which is pre-treated and ready for use;

[0044] Step (2) placing the substrate in a reaction chamber of a magnetron sputtering device, and evacuating the reaction chamber to a vacuum of 2×10 -3 Below Pa;

[0045] Step (3) introducing argon gas into the reaction chamber of the magnetron sputtering device to perform DC magnetron sputtering deposition to form a silver reflective layer on the surface of the substrate;

[0046] Step (4) introducing a mixed gas of argon and oxygen into the reaction chamber of the magnetron sputtering device to perform reactive magnetron sputtering deposition to form an aluminum oxide layer on the surface of the silver reflective layer;

[0047] Step (5) introducing a mixed gas of argon and oxygen into the reaction chamber of the magnetron sputtering device to perform reactive magnetron sputtering deposition to form a silicon oxide layer on the surface of the aluminum oxide layer;

[0048] Step (6) introduces a mixed gas of argon and oxygen into the reaction chamber of the magnetron sputtering equipment to perform DC magnetron sputtering deposition to form an indium tin oxide (ITO) layer on the surface of the silicon oxide layer to obtain an infrared suppression thermal control coating for the spacecraft thermal radiator.

[0049] Furthermore, in step (3), the conditions for DC magnetron sputtering deposition are: using a silver target, an argon gas flow rate of 200 to 1000 sccm, a deposition pressure of 0.2 to 0.8 Pa, a deposition power of 400 to 2000 W, and stopping the deposition when the thickness of the silver reflective layer reaches 100 to 400 nm.

[0050] Furthermore, in step (4), the conditions for reactive magnetron sputtering deposition are: using an aluminum target, an argon flow rate of 200 to 1000 sccm, an oxygen flow rate of 100 to 600 sccm, a deposition pressure of 0.2 to 0.8 Pa, a deposition power of 400 to 2000 W, and stopping the deposition when the thickness of the aluminum oxide layer reaches 50 to 200 nm.

[0051] Furthermore, in step (5), the conditions for reactive magnetron sputtering deposition are: using a silicon target, an argon flow rate of 200 to 800 sccm, an oxygen flow rate of 200 to 600 sccm, a deposition pressure of 0.2 to 0.8 Pa, a deposition power of 400 to 2000 W, and stopping the deposition when the thickness of the silicon oxide coating reaches 100 to 400 nm.

[0052] Furthermore, in step (6), the conditions for DC magnetron sputtering deposition are: using an indium tin oxide ceramic target, an argon flow rate of 50 to 600 sccm, an oxygen flow rate of 5 to 100 sccm, a deposition pressure of 0.2 to 0.8 Pa, and a deposition power of 200 to 1000 W. When the thickness of the indium tin oxide (ITO) layer reaches 40 to 80 nm, the deposition is stopped.

[0053] Specifically, in an embodiment of the present invention, the substrate is an aluminum alloy substrate, the reflective layer is a silver reflective layer, the oxidation inhibition layer is an aluminum oxide layer, and the emissivity regulation layer is a silicon oxide layer; the thickness of the silver reflective layer is 100nm, the thickness of the aluminum oxide layer is 100nm, the thickness of the silicon oxide layer is 200nm, and the thickness of the indium tin oxide (ITO) layer is 50nm.

[0054] Specifically, in an embodiment of the present invention, a method for preparing an infrared suppression thermal control coating of a spacecraft thermal radiator comprises the following steps:

[0055] Step (1) providing an aluminum alloy substrate, which is pre-treated and ready for use;

[0056] Step (2) placing the aluminum alloy substrate in the reaction chamber of the magnetron sputtering equipment, and evacuating the reaction chamber to a vacuum of 2×10 -3 Below Pa;

[0057] Step (3) introducing argon gas into the reaction chamber of the magnetron sputtering equipment to perform DC magnetron sputtering deposition to form a silver reflective layer on the surface of the aluminum alloy substrate; wherein the conditions of the DC magnetron sputtering deposition are: using a silver target, an argon gas flow rate of 400 sccm, a deposition pressure of 0.6 Pa, a deposition power of 600 W, and stopping the deposition when the thickness of the silver reflective layer reaches 100 nm;

[0058] Step (4) introducing a mixed gas of argon and oxygen into a reaction chamber of a magnetron sputtering device to perform reactive magnetron sputtering deposition to form an aluminum oxide layer on the surface of the silver reflective layer; wherein the conditions for reactive magnetron sputtering deposition are: using an aluminum target, an argon gas flow rate of 600 sccm, an oxygen flow rate of 200 sccm, a deposition pressure of 0.6 Pa, a deposition power of 600 W, and stopping the deposition when the thickness of the aluminum oxide layer reaches 100 nm.

[0059] Step (5) introducing a mixed gas of argon and oxygen into the reaction chamber of the magnetron sputtering equipment to perform reactive magnetron sputtering deposition to form a silicon oxide layer on the surface of the aluminum oxide layer; wherein the conditions for reactive magnetron sputtering deposition are: using a silicon target, an argon flow rate of 600 sccm, an oxygen flow rate of 300 sccm, a deposition pressure of 0.7 Pa, a deposition power of 800 W, and stopping the deposition when the thickness of the silicon oxide coating reaches 200 nm.

[0060] Step (6) introducing a mixed gas of argon and oxygen into a reaction chamber of a magnetron sputtering device to perform DC magnetron sputtering deposition to form an indium tin oxide (ITO) layer on the surface of the silicon oxide layer, thereby obtaining an infrared suppression thermal control coating for a spacecraft thermal radiator; wherein the conditions for the DC magnetron sputtering deposition are: using an indium tin oxide ceramic target, an argon flow rate of 200 sccm, an oxygen flow rate of 10 sccm, a deposition pressure of 0.4 Pa, a deposition power of 300 W, and stopping the deposition when the thickness of the indium tin oxide (ITO) layer reaches 50 nm.

[0061] The embodiment of the present invention reduces the absorption of infrared band energy by sequentially depositing a composite layer including a reflective layer, an oxidation inhibition layer, an emissivity control layer and an indium tin oxide (ITO) layer on the surface of a substrate, effectively suppresses the influence of ambient infrared thermal radiation on thermal control, and reduces the adverse influence of its own thermal radiation on infrared optical detection; at the same time, it reduces the absorption of 0.3μm to 25μm electromagnetic waves, reduces the solar absorptivity and emissivity to below 0.1, and maintains the absorption-emission ratio at 0.8 to 1.2.

[0062] The infrared suppression thermal control coating for the spacecraft thermal radiator provided by the embodiment of the present invention not only has excellent infrared suppression capability, but also has anti-static function. It exhibits good stability against space environment under the influence of humidity, heat, thermal cycle, ultraviolet radiation, particle radiation and other environmental conditions, and can be widely used in infrared suppression during radiation heat dissipation of spacecraft.

[0063] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. An infrared suppression thermal control coating for a spacecraft thermal radiator, characterized in that: It comprises a substrate, and a reflective layer, an oxidation inhibition layer, an emissivity regulating layer and an indium tin oxide (ITO) layer sequentially arranged on the surface of the substrate, wherein: The reflective layer is relatively close to the substrate, and the ITO layer is relatively far away from the substrate. The reflective layer is a silver reflective layer, The oxidation inhibition layer is an aluminum oxide layer, The emissivity regulating layer is a silicon oxide layer.

2. The infrared suppression thermal control coating for a spacecraft thermal radiator according to claim 1, characterized in that: The substrate is a rigid or flexible substrate, and the material of the substrate is an aluminum alloy, a titanium alloy, a carbon fiber composite material or a polyimide film.

3. The infrared suppression thermal control coating for a spacecraft thermal radiator according to claim 1, characterized in that: The thickness of the silver reflective layer is 100-400 nm, the thickness of the aluminum oxide layer is 50-200 nm, the thickness of the silicon oxide coating is 100-400 nm, and the thickness of the indium tin oxide (ITO) layer is 40-80 nm.

4. The infrared suppression thermal control coating for a spacecraft thermal radiator according to claim 1, characterized in that: The silver reflective layer and the indium tin oxide (ITO) layer are prepared by a direct current magnetron sputtering deposition method; the aluminum oxide layer and the silicon oxide layer are prepared by a reactive magnetron sputtering deposition method.

5. A method for preparing the infrared suppression thermal control coating of a spacecraft thermal radiator according to any one of claims 1 to 4, comprising the following steps: Step (1) providing a substrate, which is pre-treated and ready for use; Step (2) placing the substrate in a reaction chamber of a magnetron sputtering device, and evacuating the reaction chamber to a vacuum of 2×10 - 3 Below Pa; Step (3) introducing argon gas into the reaction chamber of the magnetron sputtering device to perform DC magnetron sputtering deposition to form a silver reflective layer on the surface of the substrate; Step (4) introducing a mixed gas of argon and oxygen into the reaction chamber of the magnetron sputtering device to perform reactive magnetron sputtering deposition to form an aluminum oxide layer on the surface of the silver reflective layer; Step (5) introducing a mixed gas of argon and oxygen into the reaction chamber of the magnetron sputtering device to perform reactive magnetron sputtering deposition to form a silicon oxide layer on the surface of the aluminum oxide layer; Step (6) introduces a mixed gas of argon and oxygen into the reaction chamber of the magnetron sputtering equipment to perform DC magnetron sputtering deposition to form an indium tin oxide (ITO) layer on the surface of the silicon oxide layer to obtain an infrared suppression thermal control coating for the spacecraft thermal radiator.

6. The method for preparing the infrared suppression thermal control coating of the spacecraft thermal radiator according to claim 5, characterized in that: In the step (3), the conditions for DC magnetron sputtering deposition are: using a silver target, an argon gas flow rate of 200 to 1000 sccm, a deposition pressure of 0.2 to 0.8 Pa, a deposition power of 400 to 2000 W, and stopping the deposition when the thickness of the silver reflective layer reaches 100 to 400 nm.

7. The method for preparing the infrared suppression thermal control coating of the spacecraft thermal radiator according to claim 5, characterized in that: In the step (4), the conditions for reactive magnetron sputtering deposition are: using an aluminum target, an argon flow rate of 200 to 1000 sccm, an oxygen flow rate of 100 to 600 sccm, a deposition pressure of 0.2 to 0.8 Pa, a deposition power of 400 to 2000 W, and stopping the deposition when the thickness of the aluminum oxide layer reaches 50 to 200 nm.

8. The method for preparing the infrared suppression thermal control coating of the spacecraft thermal radiator according to claim 5, characterized in that: In the step (5), the conditions for reactive magnetron sputtering deposition are: using a silicon target, an argon flow rate of 200 to 800 sccm, an oxygen flow rate of 200 to 600 sccm, a deposition pressure of 0.2 to 0.8 Pa, a deposition power of 400 to 2000 W, and stopping the deposition when the thickness of the silicon oxide coating reaches 100 to 400 nm.

9. The method for preparing the infrared suppression thermal control coating of the spacecraft thermal radiator according to claim 5, characterized in that: In the step (6), the conditions for DC magnetron sputtering deposition are: using an indium tin oxide ceramic target, an argon flow rate of 50 to 600 sccm, an oxygen flow rate of 5 to 100 sccm, a deposition pressure of 0.2 to 0.8 Pa, and a deposition power of 200 to 1000 W. When the thickness of the indium tin oxide (ITO) layer reaches 40 to 80 nm, the deposition is stopped.

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