A composite laser protection coating and a method for producing the same

Abstract

The application belongs to the field of protective coating, and particularly discloses a composite laser protective coating and a preparation method thereof. The protective coating comprises, in sequence, a high-temperature oxidation-resistant layer, a ceramic thermal insulation layer, a ceramic reflective layer and a metal reflective layer which are arranged on a substrate in a laminated manner. The porosity of the ceramic thermal insulation layer is not less than 10%. The material of the high-temperature oxidation-resistant layer comprises at least one of NiCrAlY, CoCrAlY and NiCoCrAlY. The material of the ceramic thermal insulation layer comprises zirconium oxide and an oxide doped in the zirconium oxide. The material of the ceramic reflective layer comprises zirconium oxide and a rare earth element doped in the zirconium oxide. The protective coating has a low thermal conductivity, and the average temperature on the side of the substrate away from the protective coating is lower than 150 DEG C after the substrate is continuously irradiated by a laser with a power density of 8050 W·cm ‑2 -2 for 300 s, and the bonding strength of the coating is 35-50 MPa.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of protective coating, and particularly relates to a composite laser protective coating and a preparation method thereof. BACKGROUND

[0002] High-energy laser attack is a kind of directional energy weapon using high energy of laser to destroy targets, which has the characteristics of strong killing power, low cost and strong anti-interference capability. Strong laser can cause the temperature of the material surface to rise, and the integrity, carrying capacity and functionality of the material are seriously damaged or even completely destroyed, such as burnout damage, cutting and fracture, etc. Under the action of laser, the macroscopic phenomenon is that the metal material absorbs energy, and the material surface appears temperature rise, melting, vaporization, spattering, etc. Non-metallic materials appear sublimation, chemical reaction, charring, and erosion, etc. The interaction between laser and material is mainly thermal coupling and impulse coupling effect, and the difference in parameters will lead to completely different interaction processes and different damage effects. For example, thermal ablation and thermal explosion effect impact damage and layer cracking effect and plasma cloud effect. From the micro mechanism, the interaction between laser and material is the action of high-frequency electromagnetic field on free electrons or bound electrons in the material, and the action of material on laser is closely related to the electronic band structure of the material, which is manifested in the macroscopic reflection, absorption, transmission, etc.

[0003] Thermal insulation type laser protective coating mainly relies on some low thermal conductivity materials to reduce the longitudinal transmission of laser energy and protect the substrate from ablation and structural damage. Thermal ablation principle laser protective material uses materials with high ablation heat to carry away most of the energy in the ablation process or low thermal conductivity materials to reduce the longitudinal transmission of energy. Composite laser protective coating refers to the comprehensive use of two or three protective methods, and the design of one or more layers to achieve the effect of resisting laser ablation. The application field of laser protective coating requires it to be used under high temperature, high pressure and high load conditions, and the laser protective coating is easily failed in harsh service environment, in which the oxidation failure of the reflective layer, the mass loss of the ablation layer, the insufficient effective thermal insulation of the thermal insulation layer, the poor fracture toughness, the internal stress of the coating, the sintering hardening of the ceramic layer, etc. are the main reasons for the failure of the laser protective coating.

[0004] With the entry of laser weapons into the stage of actual application, the anti-laser protection research of various unmanned / human-piloted aircrafts is imminent. The existing protective coating materials will cause problems such as oxidation of the metal reflective layer, reduction of reflectivity, mass loss of the ablation layer, insufficient toughness of the thermal insulation layer, etc. due to long-time irradiation of high-energy laser, so that the laser protective coating fails quickly and cannot meet the use requirements. SUMMARY

[0005] In order to overcome at least one technical problem existing in the prior art, one of the purposes of the present application is to provide a protective coating. The protective coating comprehensively utilizes the principles of reflection, ablation and heat insulation when protecting the substrate, and realizes good bonding strength and excellent laser radiation resistance by using the intrinsic properties of high reflectivity materials and the surface and interface reflection method of laser irradiation, thereby having excellent protective performance for the substrate.

[0006] The second purpose of the present application is to provide a preparation method of the protective coating.

[0007] The third purpose of the present application is to provide a product comprising the protective coating.

[0008] In order to achieve the above purposes, the technical solution adopted by the present application is:

[0009] The first aspect of the present application provides a protective coating, comprising a high-temperature oxidation-resistant layer, a ceramic heat-insulating layer, a ceramic reflective layer and a metal reflective layer which are sequentially stacked on a substrate, wherein the high-temperature oxidation-resistant layer and the heat-insulating ceramic layer form a gradient heat protection, and the ceramic reflective layer comprehensively utilizes its oxygen vacancy defects, porosity and interface high reflection characteristics to form effective protection against laser radiation.

[0010] The porosity of the ceramic heat-insulating layer is not less than 10%;

[0011] The material of the high-temperature oxidation-resistant layer comprises at least one of NiCrAlY, CoCrAlY and NiCoCrAlY;

[0012] The material of the ceramic heat-insulating layer comprises zirconia and an oxide doped in the zirconia; the oxide comprises at least one of Y2O3, Gd2O3, Yb2O3, TiO2 and Ta2O5;

[0013] The material of the ceramic reflective layer comprises zirconia and a rare earth element doped in the zirconia;

[0014] The number of layers of the metal reflective layer is greater than or equal to 1;

[0015] The material of each layer of the metal reflective layer is independently selected from at least one of Al, Cu, Ag, Au, NiCrAlY, CoCrAlY and NiCoCrAlY.

[0016] In the present application, the metal reflective layer and the ceramic reflective layer are arranged, and a metal-ceramic interface is formed between the two, the reflectivity of the metal reflective layer is not less than 80%, when high-energy laser irradiates on the metal reflective layer, the reflectivity of the laser on the surface of the coating layer and the metal-ceramic interface can be increased, and the longitudinal transmission of the laser energy can be reduced. In addition, the ceramic thermal insulation layer in the present application has low thermal conductivity, which can avoid the longitudinal transmission of heat. In the present application, a unique oxygen vacancy ceramic phase is constructed during the preparation of the ceramic reflective layer. In the service process, the oxygen vacancy defects act as phonon scattering centers to enhance the anharmonicity of lattice vibration, further enhance the intrinsic scattering between phonons, and thus improve the overall laser protection capability of the coating; at the same time, by controlling the porosity of the ceramic thermal insulation layer, the ceramic thermal insulation layer has high porosity, thereby increasing phonon scattering and reducing the thermal conductivity of the coating, thereby reducing the ablation and structural damage caused by laser energy to the substrate as a whole.

[0017] In some embodiments of the present application, the number of layers of the metal reflective layer is 1-2 layers.

[0018] In some embodiments of the present application, the metal reflective layer is an Al layer single-layer structure, or a double-layer structure of a NiCrAlY layer and an Al layer.

[0019] In some embodiments of the present application, the metal reflective layer comprises a NiCrAlY layer and an Al layer arranged in a stack. The NiCrAlY layer is arranged on the ceramic reflective layer. The melting point of the NiCrAlY alloy is higher than that of Al, which can improve the thermal matching between the ceramic layer and the metal layer when the high-reflectivity Al layer on the surface deforms under long-time laser irradiation, and ensure the safe service of the ceramic protective layer; Al has small density, large specific heat capacity and high reflectivity. Because the Al metal reflective layer will be rapidly oxidized to produce an aluminum oxide film under continuous irradiation of high-power laser, the reflectivity is greatly reduced, therefore, the Al metal reflective layer and the ceramic reflective layer are used at the same time, and a metal-ceramic interface is formed at the contact part of the two, so that the protective coating can greatly enhance the protection time under continuous irradiation of high-power laser on the premise of having high reflectivity.

[0020] In some embodiments of the present application, the metal reflective layer is an Al layer.

[0021] As shown in Figure 1 The protection principle of the protective coating in the present application is that a high-temperature oxidation-resistant layer, a ceramic thermal insulation layer, a ceramic reflective layer and a metal reflective layer are arranged on the surface of the substrate in sequence, and the reflection, ablation and thermal insulation principles are comprehensively utilized to further improve the laser irradiation resistance of the material.

[0022] In some embodiments of the present application, the base body is an alloy base body. In some embodiments of the present application, the base body is a titanium alloy base body or an aluminum alloy base body. Of course, other alloys can also be used as the base body in the present application, and the present application preferably uses a titanium alloy base body or an aluminum alloy base body as the base material, both of which have the advantage of being light in weight.

[0023] In some embodiments of the present application, the porosity of the ceramic thermal insulation layer is 10-20%; in some specific embodiments of the present application, the porosity of the ceramic thermal insulation layer is any one of 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20% or a range value formed by any two of them.

[0024] In some embodiments of the present application, the material of the ceramic thermal insulation layer is yttria-stabilized zirconia.

[0025] In some embodiments of the present application, the material of the ceramic thermal insulation layer comprises 5-10% yttria by mass percentage; 90-95% zirconia by mass percentage.

[0026] In some embodiments of the present application, the rare earth element is selected from at least one of ytterbium, gadolinium, and yttrium. In some embodiments of the present application, the rare earth element is selected from a mixture of ytterbium and gadolinium.

[0027] In some embodiments of the present application, the mass percentage of the rare earth element in the ceramic reflective layer is 0.5%-50%. In some specific embodiments of the present application, the mass percentage of the rare earth element is any one of 0.5%, 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50% or a range value formed by any two of them. In some embodiments of the present application, the rare earth element is composed of 1-10% ytterbium by mass percentage, 1-10% gadolinium by mass percentage, and 1-10% yttrium by mass percentage.

[0028] In some embodiments of the present application, the thickness of the high-temperature oxidation-resistant layer is 50-250 μm; in some embodiments of the present application, the thickness of the high-temperature oxidation-resistant layer is any one of 50 μm, 60 μm, 70 μm, 75 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 200 μm, 210 μm, 220 μm, 230 μm, 240 μm, 250 μm or a range value formed by any two of them.

[0029] In some embodiments of the present application, the ceramic thermal barrier layer has a thickness of 150-350 μm; in some specific embodiments of the present application, the ceramic thermal barrier layer has a thickness of any one of 150 μm, 160 μm, 170 μm, 175 μm, 180 μm, 190 μm, 200 μm, 210 μm, 220 μm, 230 μm, 240 μm, 250 μm, 260 μm, 270 μm, 275 μm, 280 μm, 290 μm, 300 μm, 310 μm, 320 μm, 330 μm, 340 μm, 350 μm or a range value formed by any two of them.

[0030] In some embodiments of the present application, the ceramic thermal barrier layer has a thickness of 150-350 μm; in some specific embodiments of the present application, the ceramic thermal barrier layer has a thickness of any one of 150 μm, 160 μm, 170 μm, 175 μm, 180 μm, 190 μm, 200 μm, 210 μm, 220 μm, 230 μm, 240 μm, 250 μm, 260 μm, 270 μm, 275 μm, 280 μm, 290 μm, 300 μm, 310 μm, 320 μm, 330 μm, 340 μm, 350 μm or a range value formed by any two of them.

[0031] In some embodiments of the present application, the metal reflective layer has a thickness of 5-50 μm; in some specific embodiments of the present application, the metal reflective layer has a thickness of any one of 5 μm, 7 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm or a range value formed by any two of them.

[0032] In some embodiments of the present application, the protective coating has a thermal conductivity of ≤1.0 W / (m·K); in some embodiments of the present application, the protective coating has a thermal conductivity of any one of 0.1 W / (m·K), 0.2 W / (m·K), 0.3 W / (m·K), 0.4 W / (m·K), 0.5 W / (m·K), 0.6 W / (m·K), 0.7 W / (m·K), 0.8 W / (m·K), 0.9 W / (m·K), 1 W / (m·K) or a range value formed by any two of them.

[0033] In some embodiments of the present application, the average temperature on the side of the substrate away from the protective coating is lower than 150℃ after continuous irradiation of the laser with a power density of 8050 W·cm -2

[0034] The second aspect of the present application provides a method for preparing the protective coating of the first aspect of the present application, comprising the following steps: ​

[0035] The anti-high-temperature oxidation layer, the ceramic thermal insulation layer, the ceramic reflection layer and the metal reflection layer are sequentially formed on the substrate to obtain the same.

[0036] In some embodiments of the present application, at least one of the anti-high-temperature oxidation layer, the ceramic thermal insulation layer, the ceramic reflection layer and the metal reflection layer is prepared by a spraying method.

[0037] In some embodiments of the present application, the spraying is at least one selected from the group consisting of high-velocity oxygen fuel spraying, atmospheric plasma spraying, low-pressure plasma spraying, plasma-physical vapor deposition and magnetron sputtering.

[0038] In some embodiments of the present application, at least one of the anti-high-temperature oxidation layer, the ceramic thermal insulation layer and the ceramic reflection layer is prepared by an atmospheric plasma spraying method.

[0039] In some embodiments of the present application, the argon flow rate in the atmospheric plasma spraying method is 25-50 L / min; in some embodiments of the present application, the argon flow rate in the atmospheric plasma spraying method is selected from any one value or a range value formed by any two values selected from the group consisting of 25 L / min, 27 L / min, 28 L / min, 30 L / min, 32 L / min, 34 L / min, 37 L / min, 40 L / min, 42 L / min, 44 L / min, 46 L / min, 47 L / min, 48 L / min and 50 L / min.

[0040] In some embodiments of the present application, the hydrogen flow rate in the atmospheric plasma spraying method is 5-30 L / min; in some embodiments of the present application, the hydrogen flow rate in the atmospheric plasma spraying method is any one value or a range value formed by any two values selected from the group consisting of 5 L / min, 6 L / min, 7 L / min, 8 L / min, 10 L / min, 12 L / min, 14 L / min, 16 L / min, 17 L / min, 18 L / min, 20 L / min, 22 L / min, 24 L / min, 25 L / min, 26 L / min, 27 L / min, 28 L / min and 30 L / min.

[0041] In some embodiments of the present application, the current in the atmospheric plasma spraying method is 500-700 A; in some embodiments of the present application, the current in the atmospheric plasma spraying method is any one of 500 A, 510 A, 520 A, 530 A, 540 A, 550 A, 560 A, 570 A, 580 A, 590 A, 600 A, 610 A, 620 A, 630 A, 640 A, 650 A, 660 A, 670 A, 680 A, 690 A, 700 A or a range formed by any two of them.

[0042] In some embodiments of the present application, the powder feeding rate in the atmospheric plasma spraying method is 10-30 g / min; in some embodiments of the present application, the powder feeding rate in the atmospheric plasma spraying method is any one of 10 g / min, 12 g / min, 14 g / min, 16 g / min, 18 g / min, 20 g / min, 22 g / min, 24 g / min, 26 g / min, 28 g / min, 30 g / min or a range formed by any two of them.

[0043] In some embodiments of the present application, the spraying distance in the atmospheric plasma spraying method is 100-300 mm; in some embodiments of the present application, the spraying distance in the atmospheric plasma spraying method is any one of 100 mm, 120 mm, 140 mm, 160 mm, 180 mm, 200 mm, 220 mm, 240 mm, 260 mm, 280 mm, 300 mm or a range formed by any two of them.

[0044] In some embodiments of the present application, the high-temperature oxidation resistant layer is prepared by the atmospheric plasma spraying method, and the parameters of the atmospheric plasma spraying method are as follows: argon flow rate 25-50 L / min, hydrogen flow rate 5-30 L / min, current 500-600 A, powder feeding rate 10-20 g / min, spraying distance 100-300 mm, and coating thickness 50-250 μm; preferably, the argon flow rate is 27 L / min, 37 L / min or 47 L / min, the hydrogen flow rate is 7 L / min, 17 L / min or 27 L / min, the current is 500 A, 550 A or 600 A, the powder feeding rate is 10 g / min, 15 g / min or 20 g / min, the spraying distance is 100 mm, 200 mm or 300 mm, and the coating thickness is 75 μm, 100 μm, 150 μm or 200 μm.

[0045] In some embodiments of the present application, the ceramic thermal insulation layer is prepared by an atmospheric plasma spraying method, and the parameters of the atmospheric plasma spraying method are as follows: argon flow rate 25-50 L / min, hydrogen flow rate 5-30 L / min, current 500-700 A, powder feeding rate 10-30 g / min, spraying distance 100-300 mm, and coating thickness 150-350 μm; preferably, the argon flow rate is 27 L / min, 30 L / min or 40 L / min; the hydrogen flow rate is 7 L / min, 15 L / min or 25 L / min; the current is 570 A, 600 A or 670 A; the powder feeding rate is 10 g / min, 20 g / min or 30 g / min; the spraying distance is 100 mm, 200 mm or 300 mm; and the coating thickness is 175 μm, 200 μm, 250 μm or 275 μm.

[0046] In some embodiments of the present application, the ceramic thermal insulation layer is prepared by an atmospheric plasma spraying method, and the parameters of the atmospheric plasma spraying method are as follows: argon flow rate 25-50 L / min, hydrogen flow rate 5-30 L / min, current 500-700 A, powder feeding rate 10-30 g / min, spraying distance 100-300 mm, and coating thickness 150-350 μm; preferably, the argon flow rate is 27 L / min, 30 L / min or 40 L / min; the hydrogen flow rate is 7 L / min, 15 L / min or 25 L / min; the current is 570 A, 600 A or 670 A; the powder feeding rate is 10 g / min, 20 g / min or 30 g / min; the spraying distance is 100 mm, 200 mm or 300 mm; and the coating thickness is 175 μm, 200 μm, 250 μm or 275 μm.

[0047] In some embodiments of the present application, the metal reflective layer is prepared by a magnetron sputtering method. The metal gas phase particles are deposited on the surface of the reflective ceramic layer by the magnetron sputtering method, and the interface reflection is further improved through the microcrystalline grain boundaries of the gas phase particles, so that the laser reflection loss is increased through interface regulation, and the longitudinal energy transmission of the laser is effectively reduced.

[0048] In some embodiments of the application, the method of magnetron sputtering has a film deposition temperature of 100-350℃. In some embodiments of the application, the method of magnetron sputtering has a film deposition temperature of any one of 100℃, 120℃, 140℃, 160℃, 180℃, 200℃, 220℃, 240℃, 260℃, 280℃, 300℃, 320℃, 350℃, or a range formed by any two of them.

[0049] In some embodiments of the application, the method of magnetron sputtering has a vacuum degree of 0.001-0.09Pa. In some embodiments of the application, the method of magnetron sputtering has a vacuum degree of any one of 0.001Pa, 0.005Pa, 0.01Pa, 0.02Pa, 0.03Pa, 0.04Pa, 0.05Pa, 0.06Pa, 0.07Pa, 0.08Pa, 0.09Pa, or a range formed by any two of them.

[0050] In some embodiments of the application, the method of magnetron sputtering has a current of 10-100A. In some embodiments of the application, the method of magnetron sputtering has a current of any one of 10A, 20A, 30A, 40A, 50A, 60A, 70A, 80A, 90A, 100A, or a range formed by any two of them.

[0051] In some embodiments of the application, the method of magnetron sputtering has a bias voltage of 50-500V. In some embodiments of the application, the method of magnetron sputtering has a bias voltage of any one of 50V, 100V, 150V, 200V, 250V, 300V, 350V, 400V, 450V, 500V, or a range formed by any two of them.

[0052] In some embodiments of the application, the method of magnetron sputtering has a gas flow of 50-500sccm. In some embodiments of the application, the method of magnetron sputtering has a gas flow of any one of 50sccm, 100sccm, 150sccm, 200sccm, 250sccm, 300sccm, 350sccm, 400sccm, 450sccm, 500sccm, or a range formed by any two of them.

[0053] In some embodiments of the present application, the metal oxide layer is prepared by magnetron sputtering, and the parameters of the magnetron sputtering are as follows: film coating temperature: 100-350℃, preferably 150℃, 250℃ or 300℃; vacuum degree: 0.001-0.09 Pa, preferably 0.005 Pa or 0.05 Pa; current: 10-100 A, preferably 10 A, 50 A or 100 A; bias voltage: 50-500 V, preferably 150 V, 250 V or 350 V; gas flow rate: 50-500 sccm, preferably 200 sccm, 300 sccm or 400 sccm; coating thickness: 5-50 μm, preferably 7 μm, 10 μm, 15 μm or 30 μm.

[0054] A third aspect of the present application provides a product comprising the protective coating of the first aspect of the present application; the product comprises a drone, an airplane, a protective mask, a fighter plane or a weapon.

[0055] The protective coating of the present application has the following beneficial effects: the protective coating of the present application constructs a unique oxygen vacancy ceramic phase in the ceramic reflective layer, and in the service process, the oxygen vacancy defects not only act as phonon scattering centers, but also enhance the anharmonicity of lattice vibration, thereby further enhancing the intrinsic scattering between phonons, thereby improving the overall thermal insulation capacity of the coating and the laser protective capacity of the coating. The present application forms a gradient protection against the longitudinal transmission of laser energy by setting the ceramic thermal insulation layer and the high-temperature oxidation-resistant layer, and has excellent bonding strength and excellent laser radiation resistance by interface regulation, specifically: the protective coating of the present application has a low thermal conductivity, and the thermal conductivity is ≤1.0 W / (m·K), and the average temperature on the side of the substrate away from the protective coating is lower than 150℃ after 300s of continuous irradiation of the laser with a power density of 8050 W·cm -2 The bonding strength of the coating is 35-50 MPa. BRIEF DESCRIPTION OF DRAWINGS

[0056] Figure 1 A laser protection schematic diagram of the composite laser protective coating in the embodiments of the present application.

[0057] Figure 2 A physical diagram of the composite laser protective coating in Example 1.

[0058] Figure 3 A physical diagram of the composite laser protective coating in Example 2 after laser irradiation. DETAILED DESCRIPTION

[0059] The specific implementation of the present application is further described in detail below in combination with the drawings and examples, but the implementation and protection of the present application are not limited thereto. It should be noted that if the following processes are not specifically described in detail, they can be implemented or understood by those skilled in the art with reference to the prior art. If the reagents or instruments used are not marked with the manufacturer, they are conventional products that can be purchased on the market.

[0060] The NiCrAlY used in the following examples and comparative examples is a nickel-based high-temperature protective coating material mainly composed of Ni (nickel), Cr (chromium), Al (aluminum), and Y (yttrium).

[0061] Example 1

[0062] This example provides a composite laser protective coating, which is arranged on a skin base body, and the composite laser protective coating is sequentially arranged from inside to outside with a high-temperature oxidation-resistant layer, a ceramic thermal barrier layer, a ceramic reflective layer, and a metal reflective layer.

[0063] The skin base body is titanium alloy.

[0064] The high-temperature oxidation-resistant layer is a NiCrAlY layer with a thickness of 100 μm.

[0065] The ceramic thermal barrier layer is a YSZ (yttria-stabilized zirconia) layer with a thickness of 175 μm, and the YSZ layer contains yttria with a mass percentage of 8%.

[0066] The ceramic reflective layer is a ZrO2 layer doped with Yb (ytterbium), Gd (gadolinium), and Y (yttrium) with a thickness of 175 μm, and the coating contains gadolinium with a mass percentage of 2.5%, ytterbium with a mass percentage of 2.5%, yttrium with a mass percentage of 5%, and zirconia with a mass percentage of 90%.

[0067] The metal reflective layer is composed of a NiCrAlY layer with a thickness of 20 μm and an Al layer with a thickness of 7 μm.

[0068] This example provides a preparation method of a composite laser protective coating, which comprises the following steps:

[0069] (1) titanium alloy is selected as the skin base body;

[0070] (2) an atmospheric plasma spraying method is used to prepare a high-temperature oxidation-resistant NiCrAlY layer with a thickness of 100 μm, and the spraying parameters are as follows: spraying distance 200 mm, argon flow rate 27 L / min, hydrogen flow rate 7 L / min, current 500 A, and powder feeding rate 10 g / min;

[0071] (3) The ceramic thermal barrier layer with a thickness of 175 μm was prepared by atmospheric plasma spraying, and the spraying parameters were as follows: spraying distance 200 mm, argon flow rate 30 L / min, hydrogen flow rate 15 L / min, current 600 A, and powder feeding rate 10 g / min;

[0072] (4) The ceramic reflective layer with a thickness of 175 μm was prepared by atmospheric plasma spraying, and the spraying parameters were as follows: spraying distance 200 mm, argon flow rate 30 L / min, hydrogen flow rate 15 L / min, current 600 A, and powder feeding rate 20 g / min;

[0073] (5) The NiCrAlY layer with a thickness of 20 μm was prepared by atmospheric plasma spraying, and the spraying parameters were as follows: spraying distance 200 mm, argon flow rate 27 L / min, hydrogen flow rate 7 L / min, current 500 A, and powder feeding rate 10 g / min;

[0074] (6) The Al layer with a thickness of 7 μm was prepared by magnetron sputtering, and the process parameters were as follows: plating temperature 150 ℃, vacuum degree 0.05 Pa, current 10 A, bias voltage 150 V, and argon flow rate 200 sccm.

[0075] The physical map of the composite laser protection coating in this example is shown in Figure 2 The coating adhesion tested according to the HB5476 standard was 41 MPa, the coating surface of the substrate after being bent by 90° was free of peeling, bulging or cracking, the coating thermal conductivity tested according to the Q / AVIC 06019 standard was 0.97 W / (m·K), and the porosity of the ceramic thermal barrier layer tested by using the Image J software was 16.6%. The composite laser protection coating in this example was continuously irradiated by a laser with a power density of 8050 W·cm -2 for 300 s, and the coating surface was free of crack or hole damage, and the highest temperature of the back surface of the skin substrate (i.e. the side away from the composite laser protection coating) was 147 ℃ and the average temperature was 84 ℃ after being continuously irradiated for 300 s.

[0076] Example 2

[0077] This example provides a composite laser protection coating, which is arranged on a skin substrate, and the composite laser protection coating sequentially comprises an anti-high-temperature-oxidation layer, a ceramic thermal barrier layer, a ceramic reflective layer and a metal reflective layer from inside to outside;

[0078] The skin substrate is an aluminum alloy;

[0079] The anti-high-temperature-oxidation layer is a NiCrAlY layer, and the thickness thereof is 100 μm;

[0080] The ceramic thermal barrier layer is a YSZ layer, and the thickness of the YSZ layer is 175 μm; the YSZ layer contains 8% yttrium oxide by mass percentage.

[0081] The ceramic reflective layer is a Yb (ytterbium), Gd (gadolinium) and Y (yttrium) doped ZrO2 layer, and the thickness of the ceramic reflective layer is 175 μm; the coating contains 2.5% gadolinium by mass percentage, 2.5% ytterbium by mass percentage, 5% yttrium by mass percentage, and 90% zirconium oxide by mass percentage;

[0082] The metal reflective layer is an Al layer, and the thickness of the metal reflective layer is 7 μm.

[0083] The example provides a preparation method of a composite laser protection coating, and the preparation method comprises the following steps:

[0084] (1) selecting an aluminum alloy as a skin matrix;

[0085] (2) preparing a NiCrAlY high-temperature oxidation-resistant layer with a thickness of 100 μm by using an atmospheric plasma spraying method, and the spraying parameters are as follows: a spraying distance of 200 mm, an argon flow rate of 27 L / min, a hydrogen flow rate of 7 L / min, an electric current of 500 A, and a powder feeding rate of 10 g / min;

[0086] (3) preparing a ceramic thermal barrier layer with a thickness of 175 μm by using an atmospheric plasma spraying method, and the spraying parameters are as follows: a spraying distance of 200 mm, an argon flow rate of 30 L / min, a hydrogen flow rate of 15 L / min, an electric current of 600 A, and a powder feeding rate of 10 g / min;

[0087] (4) preparing a ceramic reflective layer with a thickness of 175 μm by using an atmospheric plasma spraying method, and the spraying parameters are as follows: a spraying distance of 200 mm, an argon flow rate of 30 L / min, a hydrogen flow rate of 15 L / min, an electric current of 600 A, and a powder feeding rate of 20 g / min;

[0088] (5) preparing an Al metal reflective layer with a thickness of 7 μm by using a magnetron sputtering method, and the process parameters are as follows: a plating film temperature of 150 ℃, a vacuum degree of 0.05 Pa, an electric current of 10 A, a bias voltage of 150 V, and an argon gas flow rate of 200 sccm.

[0089] The coating adhesion of the composite laser protection coating in the example is 38 MPa, which is tested according to the HB5476 standard, the coating thermal conductivity is 0.81 W / (m·K), which is tested according to the Q / AVIC 06019, the coating surface of the substrate after being bent by 90° does not have peeling, bulging or cracking, which is tested according to the ASTM A1122 / A1122M-22 standard, and the porosity of the ceramic thermal barrier layer is 17.3%, which is measured by using the Image J software. The power density of the laser is 8050 W·cm -2The composite laser protective coating in this example was continuously irradiated with laser light for 300 seconds. No cracks or pores were found on the coating surface. Furthermore, the average temperature of the back side of the skin substrate after 300 seconds of continuous irradiation was a maximum of 196°C and an average of 139°C. A photograph of the coating after 300 seconds of irradiation is shown below. Figure 3 As shown, the surface discoloration is due to the reduction of oxygen-unsaturated zirconium oxide on the surface during testing in an atmospheric environment, resulting in a lighter color.

[0090] Comparative Example 1

[0091] This example provides a high-temperature anti-oxidation coating, including a high-temperature anti-oxidation layer disposed on a skin substrate; the skin substrate is a titanium alloy; the high-temperature anti-oxidation layer is a NiCrAlY layer with a thickness of 100μm.

[0092] This example provides a method for preparing a high-temperature antioxidant coating, including the following steps:

[0093] (1) Titanium alloy was selected as the skin substrate.

[0094] (2) A NiCrAlY high-temperature resistant oxide layer with a thickness of 100 μm was prepared by atmospheric plasma spraying. The spraying parameters were: spraying distance 200 mm, argon flow rate 27 L / min, hydrogen flow rate 7 L / min, current 500 A, and powder feeding rate 10 g / min.

[0095] According to the HB5476 standard, the coating adhesion of the high-temperature anti-oxidation coating in this example is 47 MPa, and the power density is 800 W·cm³. -2 The high-temperature anti-oxidation coating in this example was continuously irradiated with laser for 3 seconds. Obvious ablation holes and cracks appeared on the surface of the coating. After continuous irradiation for 3 seconds, the highest temperature on the back of the skin substrate was 532℃. The substrate deformed and failed. The reason is that the high-temperature anti-oxidation layer has a high thermal conductivity, which transfers a large amount of heat to the back of the skin substrate.

[0096] Comparative Example 2

[0097] This example provides a protective coating, which is applied to a skin substrate. The protective coating consists of a high-temperature oxidation resistant layer and a ceramic reflective layer arranged sequentially from the inside out.

[0098] The skin substrate is made of titanium alloy;

[0099] The high-temperature resistant oxide layer is a NiCrAlY layer with a thickness of 100μm;

[0100] The ceramic reflective layer is a Yb (ytterbium), Gd (gadolinium) and Y (yttrium) doped ZrO2 layer, the thickness of the ceramic reflective layer is 175 μm, the ceramic reflective layer contains 2.5% of gadolinium by mass, 2.5% of ytterbium by mass, 5% of yttrium by mass and 90% of zirconium oxide by mass;

[0101] The example provides a preparation method of the protective coating, and the preparation method comprises the following steps:

[0102] (1) titanium alloy is selected as the skin base body;

[0103] (2) a 100 μm-thick NiCrAlY high-temperature oxidation-resistant layer is prepared by using the atmospheric plasma spraying method, and the spraying parameters are as follows: a spraying distance of 200 mm, an argon flow rate of 27 L / min, a hydrogen flow rate of 7 L / min, an electric current of 500 A and a powder feeding rate of 10 g / min;

[0104] (3) a 175 μm-thick ceramic reflective layer is prepared by using the atmospheric plasma spraying method, and the spraying parameters are as follows: a spraying distance of 200 mm, an argon flow rate of 30 L / min, a hydrogen flow rate of 15 L / min, an electric current of 600 A and a powder feeding rate of 20 g / min;

[0105] The protective coating in the example cannot be reliably served due to the large difference in thermodynamic properties between the ceramic reflective layer and the high-temperature oxidation-resistant layer and the serious thermal mismatch phenomenon.

[0106] Comparative Example 3

[0107] The example provides a YSZ ceramic coating, the YSZ ceramic coating is arranged on a skin base body, and the YSZ ceramic coating sequentially comprises a high-temperature oxidation-resistant layer and a ceramic thermal barrier layer from inside to outside.

[0108] The skin base body is titanium alloy;

[0109] The high-temperature oxidation-resistant layer is a NiCrAlY layer, and the thickness of the high-temperature oxidation-resistant layer is 100 μm.

[0110] The ceramic thermal barrier layer is a YSZ layer, and the thickness of the ceramic thermal barrier layer is 175 μm; the YSZ layer contains 8% of yttrium oxide by mass.

[0111] The example provides a preparation method of the YSZ ceramic coating, and the preparation method comprises the following steps:

[0112] (1) titanium alloy is selected as the skin base body.

[0113] (2) a 100 μm-thick NiCrAlY high-temperature oxidation-resistant layer is prepared by using the atmospheric plasma spraying method, and the spraying parameters are as follows: a spraying distance of 200 mm, an argon flow rate of 27 L / min, a hydrogen flow rate of 7 L / min, an electric current of 500 A and a powder feeding rate of 10 g / min;

[0114] (3) Atmospheric plasma spraying method was used to prepare the ceramic thermal barrier layer with a thickness of 175 μm, and the spraying parameters were as follows: spraying distance 200 mm, argon flow rate 30 L / min, hydrogen flow rate 15 L / min, current 600 A, and powder feeding rate 10 g / min.

[0115] The coating adhesion of the YSZ ceramic coating in this example was 45 MPa according to the standard test of HB5476, and the porosity of the ceramic thermal barrier layer was 15.8% measured by using the Image J software. The YSZ ceramic coating in this example was continuously irradiated by the laser with a power density of 3800 W·cm -2 After 12 s of continuous irradiation, the back surface of the skin substrate had a maximum temperature of 486 ℃ and an average temperature of 417 ℃, and the substrate was deformed and failed, because the metal reflective layer and the ceramic reflective layer were not constructed, and the laser ablation on the surface of the ceramic layer was obvious.

[0116] Comparative Example 4

[0117] The laser protection coating provided in this example is arranged on a skin substrate, and the laser protection coating sequentially comprises an anti-high-temperature oxidation layer, a ceramic thermal barrier layer, and a ceramic reflective layer from inside to outside.

[0118] The skin substrate is a titanium alloy.

[0119] The anti-high-temperature oxidation layer is a NiCrAlY layer with a thickness of 100 μm.

[0120] The ceramic thermal barrier layer is a YSZ layer with a thickness of 175 μm, and the YSZ layer contains yttria with a mass percentage of 8%.

[0121] The ceramic reflective layer is a ZrO2 layer doped with Yb (ytterbium), Gd (gadolinium), and Y (yttrium) with a thickness of 175 μm, and the coating contains gadolinium with a mass percentage of 2.5%, ytterbium with a mass percentage of 2.5%, yttrium with a mass percentage of 5%, and zirconia with a mass percentage of 90%.

[0122] The example provides a preparation method of a laser protection coating, comprising the following steps:

[0123] (1) A titanium alloy is selected as the skin substrate.

[0124] (2) Atmospheric plasma spraying method is used to prepare the NiCrAlY anti-high-temperature oxidation layer with a thickness of 100 μm, and the spraying parameters are as follows: spraying distance 200 mm, argon flow rate 27 L / min, hydrogen flow rate 7 L / min, current 500 A, and powder feeding rate 10 g / min.

[0125] (3) The ceramic thermal barrier layer with a thickness of 175 μm is prepared by atmospheric plasma spraying, and the spraying parameters are as follows: spraying distance 200 mm, argon flow rate 30 L / min, hydrogen flow rate 15 L / min, current 600 A, and powder feeding rate 10 g / min;

[0126] (4) The ceramic reflective layer with a thickness of 175 μm is prepared by atmospheric plasma spraying, and the spraying parameters are as follows: spraying distance 200 mm, argon flow rate 30 L / min, hydrogen flow rate 15 L / min, current 600 A, and powder feeding rate 20 g / min.

[0127] The coating adhesion of the laser protection coating in this example is 40 MPa according to the test of the HB5476 standard, and the laser protection coating in this example is continuously irradiated by a laser with a power density of 8050 W·cm -2 for 300 s, and no obvious ablation holes and cracks appear on the surface of the coating, but the average temperature of the back surface of the skin matrix is 423 ℃ after continuous irradiation for 300 s, because the highly concentrated laser energy is not lost through the reflective part, causing the back surface temperature of the matrix to be too high, and the coating protection ability is insufficient.

[0128] Comparative Example 5

[0129] The composite laser protection coating is provided on the skin matrix, and the composite laser protection coating sequentially comprises an anti-high-temperature oxidation layer, a ceramic thermal barrier layer, a ceramic reflective layer and a metal reflective layer from inside to outside;

[0130] The skin matrix is titanium alloy;

[0131] The anti-high-temperature oxidation layer is a NiCrAlY layer with a thickness of 100 μm;

[0132] The ceramic thermal barrier layer is a YSZ layer with a thickness of 175 μm, and the YSZ layer contains yttria with a mass percentage of 8%;

[0133] The ceramic reflective layer is a ZrO2 layer doped with Yb (ytterbium), Gd (gadolinium) and Y (yttrium) with a thickness of 175 μm, and the coating contains gadolinium with a mass percentage of 2.5%, ytterbium with a mass percentage of 2.5%, yttrium with a mass percentage of 5%, and zirconia with a mass percentage of 90%;

[0134] The metal reflective layer is an Al layer with a thickness of 7 μm.

[0135] The preparation method of the composite laser protection coating comprises the following steps:

[0136] (1) Titanium alloy is selected as the skin matrix.

[0137] (2) The NiCrAlY high-temperature oxidation-resistant layer with a thickness of 100 μm was prepared by atmospheric plasma spraying, and the spraying parameters were as follows: spraying distance 200 mm, argon flow rate 27 L / min, hydrogen flow rate 7 L / min, current 500 A, and powder feeding rate 10 g / min;

[0138] (3) The ceramic thermal barrier layer with a thickness of 175 μm was prepared by atmospheric plasma spraying, and the spraying parameters were as follows: spraying distance 200 mm, argon flow rate 35 L / min, hydrogen flow rate 20 L / min, current 650 A, and powder feeding rate 12.5 g / min;

[0139] (4) The ceramic reflective layer with a thickness of 175 μm was prepared by atmospheric plasma spraying, and the spraying parameters were as follows: spraying distance 200 mm, argon flow rate 30 L / min, hydrogen flow rate 15 L / min, current 600 A, and powder feeding rate 20 g / min;

[0140] (5) The Al metal reflective layer with a thickness of 7 μm was prepared by magnetron sputtering, and the process parameters were as follows: plating temperature 150℃, vacuum degree 0.05 Pa, current 10 A, bias voltage 150 V, and argon flow rate 200 sccm.

[0141] The coating adhesion of the composite laser protection coating in the example was 47 MPa according to the test of HB5476 standard, the coating thermal conductivity was 2.4 W / (m·K) according to the test of Q / AVIC 06019 standard, and the porosity of the ceramic thermal barrier layer was 5.8% measured by Image J software. The composite laser protection coating in the example was continuously irradiated by a laser with a power density of 8050 W·cm -2 After 300 s of continuous irradiation, the surface of the coating had no crack or hole damage, and the average temperature of the back of the skin matrix (i.e. the side away from the composite laser protection coating) was 407℃ after 300 s of continuous irradiation, which was because the porosity of the ceramic thermal barrier layer was low, the effect of phonon scattering was poor, and the prepared coating had significantly weaker protection performance than the composite laser protection coating in the example with a high-porosity ceramic thermal barrier layer.

[0142] The above embodiments of the present application are described in detail, but the present application is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the purpose of the present application. In addition, the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

Claims

1. A protective coating, characterized in that: It consists of a high-temperature oxidation resistant layer, a ceramic heat insulation layer, a ceramic reflective layer and a metal reflective layer, which are sequentially stacked on the substrate. The porosity of the ceramic insulation layer is not less than 10%; The material of the high-temperature resistant oxide layer includes at least one of NiCrAlY, CoCrAlY, and NiCoCrAlY; The ceramic heat insulation layer is made of zirconium oxide and oxides doped in the zirconium oxide; the oxides include at least one of Y2O3, Gd2O3, Yb2O3, TiO2, and Ta2O5; The ceramic reflective layer is made of zirconium oxide and rare earth elements doped in the zirconium oxide; the rare earth elements are selected from at least one of ytterbium, gadolinium, and yttrium; the mass percentage of rare earth elements in the ceramic reflective layer is 0.5% to 50%. The metal reflective layer is a single-layer Al layer structure, or a double-layer structure consisting of a NiCrAlY layer and an Al layer.

2. The protective coating according to claim 1, characterized in that: The porosity of the ceramic insulation layer is 10-20%; And / or, the material of the ceramic insulation layer is yttrium-stabilized zirconium oxide.

3. The protective coating according to claim 1, characterized in that: The thickness of the high-temperature resistant oxide layer is 50~250μm; And / or, the thickness of the ceramic insulation layer is 150~350μm; And / or, the thickness of the ceramic reflective layer is 150~350μm; And / or, the thickness of the metal reflective layer is 5~50μm.

4. The protective coating according to claim 1, characterized in that: The thermal conductivity of the protective coating is ≤1.0 W / (m·K); And / or, at a power density of 8050 W·cm -2 After continuous laser irradiation for 300 seconds, the average temperature on the side of the substrate away from the protective coating is below 150°C.

5. The method for preparing the protective coating according to any one of claims 1 to 4, characterized in that: Includes the following steps: A high-temperature oxidation resistant layer, a ceramic heat insulation layer, a ceramic reflective layer, and a metal reflective layer are sequentially formed on a substrate to obtain the product.

6. The method for preparing the protective coating according to claim 5, characterized in that: At least one of the high-temperature oxidation-resistant layer, ceramic heat insulation layer, ceramic reflective layer and metal reflective layer is obtained by spraying, wherein the spraying method is selected from at least one of supersonic flame spraying, atmospheric plasma spraying, low-pressure plasma spraying, magnetron sputtering and plasma-physical vapor deposition.

7. The method for preparing the protective coating according to claim 5, characterized in that: At least one of the high-temperature oxidation-resistant layer, ceramic heat insulation layer and ceramic reflective layer is prepared by atmospheric plasma spraying. The atmospheric plasma spraying method has at least one of the following characteristics: (a1) Argon flow rate 25~50L / min; (a2) Hydrogen flow rate 5~30L / min; (a3) Current 500~700A; (a4) Powder feeding rate: 10~30g / min; (a5) Spraying distance 100~300mm.

8. The method for preparing the protective coating according to claim 5, characterized in that: The metal reflective layer is prepared by magnetron sputtering, and the magnetron sputtering method has at least one of the following characteristics: (b1) Coating temperature: 100°C~350°C; (b2) Vacuum degree: 0.001 Pa to 0.09 Pa; (b3) Current: 10A~100A; (b4) Bias voltage: 50V~500V; (b5) Gas flow rate: 50 sccm~500 sccm.

9. A product, characterized in that: The product includes the protective coating described in any one of claims 1 to 4; the product includes drones, aircraft, protective masks, fighter jets, or weapons.

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