Tungsten mesh reinforced high-temperature titanium alloy composite board with silicon carbide coating and preparation method of tungsten mesh reinforced high-temperature titanium alloy composite board

Abstract

The invention discloses a tungsten mesh reinforced high-temperature titanium alloy composite board with a silicon carbide coating and a preparation method of the tungsten mesh reinforced high-temperature titanium alloy composite board, and belongs to the technical field of composite materials. The problems that the combination effect of the tungsten mesh and the high-temperature titanium alloy is poor, and the mechanical property of the tungsten mesh reinforced high-temperature titanium alloy composite material is poor are solved. A silicon carbide coating is sprayed on the surface of a tungsten mesh, the tungsten mesh with the coating is introduced into a high-temperature titanium alloy plate, and the method specifically comprises the following steps that firstly, the tungsten mesh and the high-temperature titanium alloy plate are pretreated, the tungsten mesh is sprayed, the plate and the tungsten mesh are combined and then subjected to vacuum hot pressing sintering, and high-temperature titanium alloy is subjected to diffusion bonding through meshes of the tungsten mesh; the composite board is obtained. The silicon carbide coating is sprayed on the surface of the tungsten mesh, formation of an interface brittle phase can be inhibited, stress concentration is reduced, a matrix is protected against oxidation and hot corrosion, and the bonding capacity of a reinforcement and the matrix is improved; and meanwhile, the tungsten net can further inhibit creep deformation of the base body at high temperature.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite materials, and particularly relates to a tungsten mesh reinforced high-temperature titanium alloy composite plate with a silicon carbide coating and a preparation method thereof. Background Art

[0002] Due to its excellent specific strength, corrosion resistance and high-temperature performance, high-temperature titanium alloy has become the core structural material in the fields of aerospace, energy equipment, chemical equipment, etc. With the development of the thrust-to-weight ratio of aero-engines from 8 (8 kg of thrust per kg of engine weight) to 12+ (more than 12 kg of thrust per kg of engine weight), the working temperature of the high-pressure compressor has exceeded 600 °C, and traditional TC4 and TC11 titanium alloys are difficult to meet the working conditions of new engines. Research shows that conventional titanium alloys will show significant strength attenuation (about 40% decrease) above 500 °C, and the oxidation rate reaches 0.15 mg / cm 2 ·h at 600 °C, and there are obvious creep damage problems. This is mainly due to the limitations of the intrinsic properties of titanium alloys: the thermal stability of the α phase is insufficient at high temperatures, the β phase transformation temperature is relatively low, and the protective performance of the surface antioxidant layer is limited.

[0003] At present, the strengthening methods of high-temperature titanium alloys mainly include alloying modification, ceramic particle reinforcement and fiber / wire mesh reinforcement. Alloying modification method: By adding α-stable elements such as Al, Sn, Zr (such as Ti-1100 alloy) or β-stable elements such as Nb, Mo (such as Ti-6242S), the service temperature can be increased to 600 °C. However, when the Al content in high-temperature titanium alloys exceeds 6%, brittle Ti3Al phase is easily formed, and the increase of Mo content in high-temperature titanium alloys will significantly increase the material density (up to 4.8 g / cm 3 ), which conflicts with the lightweight requirement. Ceramic particle reinforcement method: Using in-situ self-reinforcing phases such as TiB and TiC (such as TiBw / Ti composites), the room temperature strength can reach 1450 MPa, but at high temperature (600 °C), interface debonding leads to the strength retention rate of high-temperature titanium alloys being only 55-60%. Although adding SiC particles (5-10 vol%) can improve the high-temperature performance, it will reduce the ductility of high-temperature titanium alloy materials (elongation < 3%). Fiber / wire mesh reinforcement method: Continuously reinforced SiC fiber titanium matrix composites (such as SCS-6 / Ti) have excellent high-temperature performance, but there are problems of high fiber cost and interface microcracks caused by the mismatch of thermal expansion coefficients with the matrix (CTE difference is about 4.5×10 -6 / K).

[0004] In the fiber / wire mesh reinforcement method, tungsten mesh has certain advantages as a reinforcement due to its high melting point and good high-temperature stability. However, there are two major challenges in the composite of tungsten mesh and high-temperature titanium alloy: one is the mutual diffusion of W and Ti at high temperatures to form a brittle TiW2 phase (the thickness of the interfacial layer reaches 15 μm after treatment at 800 °C for 2 h); the other is the volatilization of WO3 generated by the oxidation of the tungsten mesh surface during high-temperature service, resulting in interfacial voids. In addition to the above two reasons, there are also problems such as low bonding strength at the interface in the composite of tungsten mesh and high-temperature titanium alloy, which also weakens the mechanical properties and high-temperature stability of the composite material and affects its use in high-temperature environments. Summary of the Invention

[0005] In order to solve the problems in the prior art such as the low bonding ability between tungsten mesh and high-temperature titanium alloy and the poor mechanical properties of tungsten mesh-reinforced high-temperature titanium alloy composite materials, the present invention provides a tungsten mesh-reinforced high-temperature titanium alloy composite plate with a silicon carbide coating and a preparation method thereof.

[0006] To solve the above technical problems, the present invention is achieved through the following technical solutions:

[0007] The object of the present invention is to provide a preparation method of a tungsten mesh-reinforced high-temperature titanium alloy composite plate with a silicon carbide coating, including:

[0008] Step 1: Grind the plate smoothly, remove the surface oil stain, remove impurities on the plate by pickling, and wash and dry it with ethanol for standby;

[0009] Step 2: Take the tungsten mesh for alkali washing and dry it for standby;

[0010] Step 3: Place the tungsten mesh on a flat plate and perform sandblasting or machining on the tungsten mesh;

[0011] Step 4: Preheat the tungsten mesh treated in Step 3, and after preheating, perform plasma spraying on the tungsten mesh with composite powder to obtain a tungsten mesh with a coating;

[0012] Step 5: Take two plates reserved in Step 1 and a tungsten mesh with a coating in Step 4, spray a release agent on the two plates respectively, and then stack them in the order of plate, tungsten mesh with a coating, and plate from bottom to top. After stacking, tie and fix them with iron wire to obtain a combined plate;

[0013] Step 6: Spray a release agent on the part of the vacuum hot press sintering mold that is in direct contact with the lower surface of the combined plate, and dry it after spraying;

[0014] Step 7: Place the combined plate in the vacuum hot press sintering mold, and then put the combined plate together with the vacuum hot press sintering mold into a vacuum hot press sintering furnace for vacuum hot press sintering. After sintering, cool down and take out the parts;

[0015] Step 8: grinding the surface of the combined plate after vacuum hot pressing and sintering to obtain a tungsten mesh reinforced high-temperature titanium alloy composite plate with a coating;

[0016] In step 5, the positions where the release agent is sprayed on the two plates are both: the other side of the contact surface that contacts the tungsten mesh with the coating.

[0017] It is further defined that the plate material in step 1 is a high temperature titanium alloy.

[0018] It is further defined that the liquid used in the pickling process in step 1 is a mixed liquid composed of hydrofluoric acid, nitric acid and water in a volume ratio of 1:3:6, and the pickling time is 1 to 4 minutes.

[0019] It is further defined that the concentration of the hydrofluoric acid and the nitric acid are both 90%.

[0020] It is further defined that in step 2, the tungsten mesh is made by weaving, and the nodes have welding points.

[0021] It is further defined that the solution used in the alkali washing process in step 2 is a 50wt% NaOH solution, the alkali washing temperature is 80-100°C, the alkali washing time is 10-14h, and the alkali washing process is heated in a water bath.

[0022] It is further defined that the composite powder in step 4 is a powder composed of zirconium oxide and silicon carbide in a volume ratio of 3:7.

[0023] It is further defined that the plasma spraying parameters in step 4 are: spraying current 700-750A, spraying voltage 65-75V, spraying distance 100-140mm, plasma gas is hydrogen, hydrogen flow rate is 10-20L / min, powder feeding gas is argon, and powder feeding flow rate is 5-10L / min.

[0024] It is further defined that the vacuum degree of vacuum hot pressing sintering in step 7 is not less than 1×10 -2 Pa, the hot pressing sintering pressure is 10-50MPa, and the temperature is 860-960℃.

[0025] The second object of the present invention is to provide a tungsten mesh reinforced high-temperature titanium alloy composite plate with a silicon carbide coating prepared by the above method.

[0026] The beneficial effects of the present invention are:

[0027] The present invention provides a tungsten mesh-reinforced high-temperature titanium alloy composite plate with a silicon carbide coating and a preparation method thereof, realizing the composite of a tungsten mesh with a silicon carbide coating and a high-temperature titanium alloy material. The tungsten mesh (W content ≥ 99.95%) has unique advantages as a reinforcement. It has a high melting point (about 3422 °C), and the mesh structure of the tungsten mesh can provide three-dimensional continuous support in the composite plate, avoiding the anisotropy of traditional fiber reinforcement. In addition, compared with traditional ceramic reinforcements, the tungsten mesh has a higher CTE matching with the high-temperature titanium alloy in a high-temperature environment (the CTE of tungsten is about 6.2×10 -6 / K, and that of the high-temperature titanium alloy is about 8.6×10 -6 / K), which is beneficial to reducing thermal stress and avoiding the interface cracking between the alloy matrix and the reinforcement at high temperature, resulting in a decline in mechanical properties. Compared with the prior art, the present invention also has the following advantages:

[0028] (1) The present invention uses the plasma spraying method to prepare a silicon carbide (SiC) coating with a thickness of 10 - 50 μm on the surface of the tungsten mesh. This coating has multiple functions. First, it can serve as a diffusion barrier layer: SiC reacts with Ti to form Ti5Si3 (ΔG = -185 kJ / mol). At the same ambient temperature, the ΔG of this reaction is lower than that of the reaction between W and Ti, so the reaction tendency is stronger. Therefore, the presence of SiC effectively inhibits the formation of the brittle phase TiW2 at the interface, thereby improving the bonding strength at the interface between the high-temperature titanium alloy material and the tungsten mesh and making their bonding effect better; the second function is to serve as a stress buffer layer: in the composite plate, the SiC (CTE = 4.3×10 -6 / K) coating is sprayed on the surface of the tungsten mesh. The SiC coating is between the tungsten mesh and the high-temperature titanium alloy matrix, acting as an intermediate layer, which can absorb the thermal stress during the use of the composite plate and reduce the thermal stress between the tungsten mesh and the high-temperature titanium alloy matrix.

[0029] (2) The present invention sprays a SiC coating on the tungsten mesh. SiC has a high melting point and can still maintain excellent oxidation resistance and chemical inertness at high temperatures, without softening or phase change due to high temperature, so that the composite plate can still maintain good mechanical properties in extreme high-temperature environments, and it is not easy to crack at the interface with the high-temperature titanium alloy matrix; at the same time, the thermal expansion coefficient of SiC is close to that of the high-temperature titanium alloy matrix, which can reduce the thermal stress mismatch between the SiC coating and the high-temperature titanium alloy matrix at high temperatures, avoiding interface cracking or coating peeling, and the high thermal conductivity of SiC helps the composite plate to dissipate heat quickly in a high-temperature environment, improving the thermal stability of the composite plate.

[0030] (3) The high-temperature resistance of the composite board prepared by the method provided by the present invention is enhanced. In the present invention, a composite powder with SiC and zirconium oxide (ZrO2) as raw materials is sprayed on the tungsten mesh, thereby preparing a SiC coating on the tungsten mesh. Among them, the role of zirconium oxide is to act as a binder to enhance the adhesion of SiC on the tungsten mesh, so as to successfully prepare a SiC coating on the tungsten mesh. This coating has excellent high-temperature oxidation resistance, can withstand temperatures above 1200 °C, and also has high stability at high temperatures, thereby improving the interface stability and inhibiting the creep deformation of the composite board at high temperatures.

[0031] (4) The method provided by the present invention optimizes the thermal stability of the tungsten mesh-reinforced composite board. In a high-temperature environment, the tungsten mesh in the tungsten mesh-reinforced high-temperature titanium alloy composite board will expand in volume when heated, thereby generating stress and deformation. At this time, the SiC coating sprayed on the outside of the tungsten mesh can wrap the tungsten mesh and play a role in confining the tungsten mesh, avoiding the deformation of the tungsten mesh, thereby reducing the thermal stress concentration at the interface. This reduction in thermal stress concentration, in turn, can prevent the peeling of the SiC coating and prevent the cracking of the high-temperature titanium alloy matrix, and improve the interfacial bonding strength between the reinforcement and the matrix.

[0032] (5) The present invention uses the plasma spraying process to prepare a SiC coating on the tungsten mesh. During the spraying process, by adjusting the parameters, the SiC coating has a suitable porosity and has a high bonding strength with the tungsten mesh. In addition, the present invention adopts a pre-diffusion treatment technology for the composite of the tungsten mesh and the high-temperature titanium alloy matrix to ensure the metallurgical bonding of the multi-layer structure interface, and further optimizes the interfacial bonding strength between the tungsten mesh and the high-temperature titanium alloy matrix.

[0033] (6) The present invention first performs plasma spraying and then vacuum hot pressing and sintering, avoiding the damage to the material properties caused by high-temperature sintering in the preparation of traditional composite boards, and is suitable for the batch production of composite boards with complex shapes, and has high process compatibility. Description of the Drawings

[0034] Figure 1 Schematic diagram of the diffusion bonding of the Ti60 high-temperature titanium alloy board in Example 1 through a tungsten mesh with a silicon carbide coating. 1 is the Ti60 high-temperature titanium alloy board, and 2 is the tungsten mesh with a silicon carbide coating;

[0035] Figure 2 Schematic diagram of the vacuum hot pressing and sintering mold in Example 1. Among them, 1 is the punch, 2 is the die, and 3 is the spacer block;

[0036] Figure 3 Schematic diagram of the plasma spraying process in Example 1. Among them, 1 is the nozzle, 2 is the positive electrode lead and contact tip, 3 is the wire guide, 4 is the driving roller, 5 is the atomizing air input, 6 is the negative electrode lead and contact wire end, and 7 is the tungsten mesh;

[0037] Figure 4 The coating adhesion conditions of the tungsten mesh after plasma spraying with different powders for Example 1 and Comparative Examples 1-2 are shown. (a) Pure tungsten mesh, (b) Comparative Example 1, (c) Comparative Example 2, (d) Example 1;

[0038] Figure 5 The cross-sectional microstructure morphology diagram and the enlarged microstructure morphology diagram of the composite plate prepared in Example 1 are shown. Among them, 1 is the tungsten wire in the tungsten mesh, and 2 is the SiC coating;

[0039] Figure 6 The room-temperature mechanical property comparison diagram of the composite plate prepared in Example 1 and the Ti60 high-temperature titanium alloy plate;

[0040] Figure 7 The high-temperature mechanical property comparison diagram of the composite plate prepared in Example 1 and the Ti60 high-temperature titanium alloy plate;

[0041] Figure 8 The interface shear strength comparison diagram of the composite plates prepared in Example 1 and Comparative Example 3. Detailed implementation manners

[0042] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following describes the detailed implementation manners of the present invention in combination with the embodiments of the specification.

[0043] Many specific details are set forth in the following description to facilitate a thorough understanding of the present invention. However, the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0044] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that can be included in at least one implementation manner of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it an individual or alternative embodiment that is mutually exclusive with other embodiments.

[0045] The experimental methods used in the following embodiments are all conventional methods unless otherwise specified. The materials, reagents, methods, and instruments used, unless otherwise specified, are all conventional materials, reagents, methods, and instruments in this field, and those skilled in the art can obtain them through commercial channels.

[0046] The silicon carbide elemental powder and the silicon carbide spraying powder in the following comparative examples are purchased from Harbin Peize Material Technology Co., Ltd.

[0047] Example 1

[0048] Step 1: Polish a Ti60 high-temperature titanium alloy plate with dimensions of 50 mm × 50 mm and a thickness of 2 mm until it is flat, and remove the oil on the surface. During the polishing stage, ensure that the plate is smooth and has no obvious deformation. After polishing, pickle the plate with a combined liquid of hydrofluoric acid: nitric acid: water (volume ratio) of 1:3:6 for 2 min to remove impurities. After that, clean it with absolute ethanol, dry it, and set it aside for later use;

[0049] Step 2: Take a pure tungsten tungsten mesh (50 mm × 50 mm) woven with solder joints at the nodes, wash it with absolute ethanol, dry it, prepare a NaOH solution with a concentration of 50 wt%, and perform alkali washing on the dried tungsten mesh. The alkali washing is carried out by water bath heating, with an alkali washing temperature of 100 °C and a time of 12 h. After the alkali washing, dry it with absolute ethanol and set it aside for later use;

[0050] Step 3: Place the tungsten mesh on a flat plate, and increase its surface roughness by sandblasting or machining. After processing one side, flip the tungsten mesh and process it again to ensure that the surface of the tungsten wire of the tungsten mesh is completely processed and has a certain roughness;

[0051] Step 4: Preheat the tungsten mesh (preheating temperature is 200 °C) to reduce thermal stress. Perform plasma spraying with a composite powder composed of zirconia and silicon carbide in a volume ratio of 3:7. The plasma spraying process parameters are: spraying current 700 - 750 A, spraying voltage 65 - 75 V, spraying distance 120 mm, plasma gas is hydrogen, hydrogen flow rate 15 L / min, powder feeding gas is argon, powder feeding flow rate 7 L / min. After spraying, let it cool naturally to prevent the coating from cracking. After cooling to room temperature, observe whether the surface of the coating is uniform and has no cracks, and form a SiC coating with a thickness of 10 - 50 μm on the surface of the tungsten mesh;

[0052] Step 5: Take two pieces of the Ti60 high-temperature titanium alloy plate prepared in Step 1 and one tungsten mesh sprayed with a SiC coating in Step 4. Spray the release agent boron nitride on each of the two Ti60 high-temperature titanium alloy plates. Only spray one side of the plate, and there is no need to spray both sides. After the boron nitride spraying is completed, dry it. Then stack them in order from bottom to top as Ti60 high-temperature titanium alloy plate, tungsten mesh with SiC coating, and Ti60 high-temperature titanium alloy plate. Among them, the side of the bottom Ti60 high-temperature titanium alloy plate sprayed with boron nitride faces down, and the side of the top Ti60 high-temperature titanium alloy plate sprayed with boron nitride faces up, that is, the positions where the two plates are sprayed with the release agent are on the other side of the contact surface in contact with the coated tungsten mesh. To keep the positions of the Ti60 high-temperature titanium alloy plate and the tungsten mesh fixed during the vacuum hot pressing and sintering process, tie the stacked plates and the tungsten mesh with SiC coating firmly with a wire with a diameter of 0.1 mm to obtain a composite plate with a combination form of Ti60 high-temperature titanium alloy / tungsten mesh with SiC coating / Ti60 high-temperature titanium alloy;

[0053] Step 6: Spray the parting agent boron nitride on the part of the vacuum hot pressing and sintering die that is in direct contact with the lower surface of the composite plate. After spraying, dry it with a hair dryer.

[0054] Step 7: Place the composite plate in the vacuum hot pressing and sintering die, then put the composite plate together with the vacuum hot pressing and sintering die into the vacuum hot pressing and sintering furnace. Evacuate the vacuum hot pressing and sintering furnace to 1×10 -2 Pa, set the heating temperature to 900 °C, the holding time to 120 min, the pressure to 7500 Kg (30 MPa), and the heat preservation and pressure holding time to 2 h. After setting the parameters, carry out vacuum hot pressing and sintering. After sintering, cool down to room temperature and take out the parts.

[0055] Step 8: Grind the composite plate after vacuum hot pressing and sintering to remove the surface interference layer, and obtain a tungsten mesh reinforced Ti60 high-temperature titanium alloy composite plate with a SiC coating.

[0056] During the process of vacuum hot pressing and sintering forming in Step 7 of this embodiment, the deformation process between the Ti60 high-temperature titanium alloy plate and the tungsten mesh sprayed with a silicon carbide coating is as Figure 1 shown. When the temperature rises to the deformation temperature range of the Ti60 high-temperature titanium alloy plate, the plate gradually softens, meets the Ti60 high-temperature titanium alloy plate on the other side through the mesh holes of the tungsten mesh, and element diffusion occurs and then they are connected together. The schematic diagram of the vacuum hot pressing and sintering die used in this embodiment is as Figure 2 shown. The stacked composite plates are placed on the spacer blocks. Figure 3 This is the schematic diagram of the plasma spraying process in this embodiment.

[0057] Figure 5 This is the cross-sectional state of the composite plate prepared in this embodiment. It can be seen that the tungsten wires in the tungsten mesh with a silicon carbide coating are completely embedded in the high-temperature titanium alloy matrix, and the high-temperature titanium alloy itself has good diffusion. Figure 6 This is the comparison chart of the room temperature mechanical properties between the composite plate prepared in this embodiment and the Ti60 high-temperature titanium alloy plate. It can be seen that the tensile strength of the composite plate has been greatly improved compared with the performance before strengthening. This is because the SiC silicon carbide coating on the tungsten mesh becomes denser after vacuum hot pressing and sintering and has good mechanical properties. Figure 7 This is the comparison chart of the high-temperature mechanical properties between the composite plate prepared in this embodiment and the Ti60 high-temperature titanium alloy plate. To ensure the accuracy of the data, three experiments were carried out on the composite plate, which are the three curves in red, blue and green in the figure. The orange curve is the test curve of the Ti60 high-temperature titanium alloy plate. It can be seen that the high-temperature mechanical properties of the composite plate have been greatly improved. This is because the SiC coating has good high-temperature resistance, which greatly improves the creep resistance of the high-temperature titanium alloy matrix.

[0058] Comparative Example 1

[0059] The difference between this comparative example and Example 1 lies in that: the powder used in plasma spraying in Step 4 is silicon carbide elemental powder, and the remaining process steps and parameter settings are the same as those in Example 1.

[0060] Comparative Example 2

[0061] The difference between this comparative example and Example 1 lies in that: the powder used in plasma spraying in Step 4 is silicon carbide spraying powder, and the remaining process steps and parameter settings are the same as those in Example 1.

[0062] Comparative Example 3

[0063] The difference between this comparative example and Example 1 lies in that: the tungsten mesh sprayed with SiC coating in Step 5 is replaced with a pure tungsten mesh without coating, Steps 3 and 4 are absent, and the remaining process steps and parameter settings are the same as those in Example 1, obtaining a tungsten mesh reinforced Ti60 high-temperature titanium alloy composite plate.

[0064] Figure 4 Shown are a photo of the tungsten mesh without silicon carbide coating and the effect diagrams of spraying coatings on tungsten wires with different powders in Step 4 of Example 1 and Comparative Examples 1-2. By comparing with the tungsten mesh without coating, it is found that the composite powder has a good spraying effect. The powder is evenly sprayed on the surface of the tungsten wire, and the formed coating state is uniform, without local over-thickness or powder hanging, and there is no unsprayed state. In contrast, the coatings sprayed with silicon carbide elemental powder in Comparative Example 1 and the coatings sprayed with silicon carbide spraying powder in Comparative Example 2 both show non-uniform states, with some tungsten wires not covered by the coating or having over-thick coatings, which are not conducive to improving the bonding effect between the reinforcement and the high-temperature titanium alloy matrix.

[0065] Figure 8 Shown is a comparison diagram of the interfacial shear strength of the composite plates prepared in Example 1 and Comparative Example 3. It can be seen that the interfacial shear strength of the composite plate in Example 1 is significantly higher than that of the composite plate in Comparative Example 3, indicating that the interfacial bonding strength of the composite plate in Example 1 has been greatly improved compared to Comparative Example 3. This is mainly because the SiC coating can form chemical bonding with the high-temperature titanium alloy matrix at high temperature, thus improving the bonding strength.

[0066] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent replacements or changes, and all should be covered within the protection scope of the present invention.

Claims

1. A preparation method of a tungsten mesh-reinforced high-temperature titanium alloy composite plate with a silicon carbide coating, characterized in that, Including: Step 1: Polish the sheet metal to make it flat, remove the surface oil stain, remove impurities on the sheet metal by pickling, and wash it with ethanol, then dry it for standby; Step 2: Take the tungsten mesh and perform alkali washing, then dry it for standby; Step 3: Place the tungsten mesh on a flat plate and perform sandblasting or machining on the tungsten mesh; Step 4: Preheat the tungsten mesh processed in Step 3, and after preheating, perform plasma spraying on the tungsten mesh with composite powder to obtain a tungsten mesh with a coating; Step 5: Take two sheets of the sheet metal reserved in Step 1 and a tungsten mesh with a coating in Step 4, spray a release agent on the two sheets of sheet metal respectively, and then stack them in order from bottom to top as sheet metal, tungsten mesh with a coating, and sheet metal. After stacking, tie and fix them with iron wire to obtain a composite sheet; Step 6: Spray a release agent on the part of the vacuum hot pressing and sintering mold that is in direct contact with the lower surface of the composite sheet, and dry it after spraying; Step 7: Place the composite sheet in the vacuum hot pressing and sintering mold, then put the composite sheet together with the vacuum hot pressing and sintering mold into a vacuum hot pressing and sintering furnace for vacuum hot pressing and sintering. After sintering, cool down and take out the part; Step 8: Polish the surface of the composite sheet after vacuum hot pressing and sintering to obtain a tungsten mesh-reinforced high-temperature titanium alloy composite sheet with a coating; In Step 5, the positions where the release agent is sprayed on the two sheets of sheet metal are both: the other side of the contact surface that contacts the tungsten mesh with a coating.

2. The preparation method according to claim 1, characterized in that, The material of the sheet metal in Step 1 is high-temperature titanium alloy.

3. The preparation method according to claim 1, characterized in that, In Step 1, the liquid used in the pickling process is a mixed liquid composed of hydrofluoric acid, nitric acid and water in a volume ratio of 1:3:6, and the pickling time is 1 - 4 min.

4. The preparation method according to claim 3, characterized in that, The concentrations of hydrofluoric acid and nitric acid are both 90%.

5. The preparation method according to claim 1, wherein In Step 2, the tungsten mesh is made by a weaving method and the nodes have solder joints.

6. The preparation method according to claim 1, characterized in that, In Step 2, the solution used in the alkali washing process is a 50wt% NaOH solution, the alkali washing temperature is 80 - 100 °C, the alkali washing time is 10 - 14 h, and the alkali washing process is water bath heating.

7. The preparation method according to claim 1, wherein In Step 4, the composite powder is a powder composed of zirconia and silicon carbide in a volume ratio of 3:

7.

8. The preparation method according to claim 1, characterized in that, In Step 4, the plasma spraying parameters are: spraying current 700 - 750 A, spraying voltage 65 - 75 V, spraying distance 100 - 140 mm, the plasma gas is hydrogen, the hydrogen flow rate is 10 - 20 L / min, the powder feeding gas is argon, and the powder feeding flow rate is 5 - 10 L / min.

9. The preparation method according to claim 1, wherein, The vacuum degree of vacuum hot pressing sintering in step 7 is less than 1×10 -2 Pa, the hot pressing sintering pressure is 10-50 MPa, and the temperature is 860-960 °C.

10. A tungsten mesh-reinforced high-temperature titanium alloy composite plate with a silicon carbide coating, characterized in that, Prepared by the method according to any one of claims 1 - 9.

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