Method for repairing through hole of metal part by means of easy-to-disassemble gauze

Abstract

The invention relates to a method for repairing a through hole of a metal part by means of an easy-to-disassemble gauze element, which comprises the following steps of: carrying out polishing treatment and surface treatment on the periphery of the through hole of the metal part, and fixing a flexible compact gauze element on the metal surface on one side of the through hole of the metal part by using a high-temperature-resistant adhesive tape to serve as an effective deposition matrix for repairing powder in the next step; a spraying process with the gas inlet temperature being 400-550 DEG C, the gas pressure being 110-130 psi, the powder feeding amount being 12-15 g / min and the spraying distance being 10-25 mm is adopted, and the repairing powder is sprayed and repaired from an opening in the other side of the through hole of the metal part; and a polishing step. According to the method, the problem that in an existing cold spraying repairing method, a supporting plate and a repairing part are difficult to disassemble is solved. The unique design of the gauze element enables the upholder to be easily dismantled after repairing is completed, additional heat treatment is not needed, and the method is suitable for on-site repairing of complex holes of various metal parts, has wide application potential and particularly has important application value in the industries of aviation, automobiles, buildings and the like.

Description

Technical Field

[0001] The invention relates to the field of surface engineering and additive manufacturing technology, and in particular to a method for repairing a through hole of a metal component by means of an easily detachable gauze. Background Art

[0002] Cold spray technology is a solid deposition process based on high-speed gas flow, which accelerates micron-sized metal particles to 300 to 1200 m / s and impacts the substrate surface in an unmelted state to form a deposition layer. Compared with traditional thermal spraying and welding methods, cold spray technology has significant advantages in many aspects. Its low temperature characteristics avoid the problems of oxidation, pore formation and composition segregation that may occur during the melting process of the material, thereby achieving an oxidation-free, high-density deposition structure. At the same time, due to the small heat-affected zone of cold spraying, the physical and chemical properties of the substrate are effectively retained, avoiding the risk of substrate deformation and microstructural damage during thermal processing. Due to these advantages, cold spray technology has been widely used in the repair and additive manufacturing of metal parts, especially in large-area repair and processing of special-shaped structural parts.

[0003] In the specific application of cold spraying technology, the repair of through holes in metal parts (such as penetrating defects or damage in mechanical components) is still a technical challenge. The shape and size of the through holes usually have large irregularities, which makes it easy for the sprayed powder particles to penetrate through the holes and cannot be evenly filled, thus affecting the density and strength of the deposited layer. At present, conventional methods for repairing through holes usually require the arrangement of supporting materials or filling structures on the back of the holes to provide auxiliary support. However, the supporting materials in the prior art are usually inseparable from the repaired components. Such inseparability not only reduces the quality of the repaired components, but may also have an adverse effect on the performance and subsequent processing of the components.

[0004] To solve the above problems, some studies have proposed design solutions for detachable support structures. However, these support structures often face many limitations in actual operation. For example, due to the complex structure of some designs, the positioning and fixing operations of the support device on the back of the through-hole are extremely cumbersome. At the same time, in order to achieve the disassembly of the support material, special tools or additional machining steps may be required after the repair, which not only significantly increases the process cost and repair time, but also may cause secondary damage to the integrity and performance of the repaired area. How to develop a through-hole repair support that is easy to operate, has stable performance and is easy to disassemble is still a difficult problem in cold spray repair technology, which is also the task of the present invention. Summary of the invention

[0005] The purpose of the present invention is to avoid the shortcomings of the prior art and provide a method for repairing the through hole of a metal component by means of an easily detachable gauze which is simple, low in cost and has a good modification effect.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a method for repairing a through hole of a metal component by means of an easily detachable gauze, comprising the following steps: Step 1: Grind and surface treat the area around the through hole on the metal part to enhance the bonding strength between the repair powder and the matrix; Step 2: Use a high temperature resistant tape to fix the flexible dense gauze on the surface of the metal component on one side of the through hole of the metal component. The flexible dense gauze and the hole body constitute an effective deposition matrix for the repair powder. Step 3: Fix the metal part on the fixture, and spray the repair powder from the through hole opening of the deposition substrate under the condition that the spray gas source is pure helium, with the spray gas inlet temperature of 400-550°C, pressure of 110-130psi, spray powder feeding amount of 12-15 g / min, and spray distance of 10-25 mm. The caliber of the spray gun muzzle of the spray equipment is not larger than the diameter of the through hole. During spray repair, the spray gun muzzle is kept at 90° to the inner wall of the through hole opening, and spray gradually in a spiral route from the inner wall edge close to the through hole to the center of the hole at a uniform speed. After 2-3 sprayings in this way, a conical protrusion with a vertex angle of 10-20° is formed in the center of the hole. The area around the protrusion is the spray dead zone, and the repair powder cannot be deposited. At this time, the protrusion is polished to be flush with the lowest point of the repair layer. After polishing, spray again in a spiral route to the center of the hole. When a protrusion is formed again, it is polished to be flush with the lowest point of the repair layer. Repeat this process until the repair is completed; Step 4: After spraying, remove the screen and polish the coating surface to ensure a smooth transition between the filler layer and the metal part surface.

[0007] Furthermore, in step 1, the grinding process is to grind the inner wall surfaces of the through hole at both sides of the through hole into a groove with an angle of 70-80° to facilitate the deposition of the repair powder; The surface treatment is to perform sandblasting or laser scanning on the metal surface around the through hole of the metal component to remove impurities or oxide film on the surface of the metal component.

[0008] Furthermore, in step 2, the material of the flexible dense gauze is a metal fiber material or alloy fiber material that is resistant to high temperature and has strong oxidation resistance; the thickness of the flexible dense gauze is 0.5-2mm, the wire diameter is 0.1-0.3mm, the mesh number is at least 1200 mesh, and the particle size of the repair powder is 23-50μm, ensuring that the flexible dense gauze can prevent the repair powder from being directly sprayed out of the through hole under the conditions of spraying pressure and airflow, and at the same time, facilitate the airflow to pass through without causing reverse pressure, thereby ensuring that the powder in the through hole flows evenly and improving the deposition effect.

[0009] Specifically, when the mesh is too thin, it may not be able to effectively block the powder during the spraying process, especially under higher airflow and spraying pressure, causing the powder to leak out from the back of the hole, affecting the repair effect. Mesh damage: Thinner mesh may be easily damaged by the impact under high spraying pressure, causing the mesh to fail during the spraying process, thus affecting the repair quality.

[0010] However, when the mesh is too thick, especially when using coarse materials, it may cause too much resistance to the airflow, resulting in the airflow not being able to pass smoothly, affecting the uniformity of the spraying and the deposition quality of the powder. It will also cause the coating adhesion to decrease. Too thick a mesh may cause uneven powder flow during the spraying process, poor coating deposition, and affect the quality of the repair layer. It also increases the difficulty of operation. Thick meshes are prone to cause greater reverse pressure, and higher airflow pressure may be required during spraying, which may increase the complexity of the operation and consume more gas and energy.

[0011] Furthermore, the metal fiber material is stainless steel fiber, nickel fiber, titanium fiber; the alloy fiber material is iron-chromium-aluminum alloy fiber, constantan fiber, Inconel alloy fiber.

[0012] Furthermore, in step three, the spraying powder material used in the spraying process is metal or metal-ceramic mixed powder; the metal is Al and Al alloys, Mg and Mg alloys, Cu and Cu alloys, Ti and Ti alloys, and the ceramic is Al2O3, SiC, TiN.

[0013] Furthermore, the material of the metal component is metal and its alloy or ceramic-metal matrix composite material; the metal and alloy are Al and Al alloy, Mg and Mg alloy, Cu and Cu alloy, Ti and Ti alloy; the ceramic-metal matrix composite material is Al2O3 reinforced metal matrix composite material, SiC reinforced metal matrix composite material, TiN reinforced metal matrix composite material.

[0014] Furthermore, the through hole on the metal component has a depth of 3-15 mm and a radius of 3-10 mm.

[0015] Specifically, when the depth of the through hole is less than 3 mm, the local temperature of the metal part will be too high during the spraying process, resulting in deformation or warping; when the depth is greater than 15 mm, it is difficult for the repair powder to adhere evenly, which may cause the repair layer to fall off.

[0016] At the same time, when the radius of the through hole is less than 3 mm, the repair powder cannot completely cover the inner edge area of ​​the hole; when the radius is greater than 10 mm, the repair powder can only adhere to the edge of the hole and it is difficult to fill the center area of ​​the hole, thus forming a gap.

[0017] Furthermore, the spraying equipment is a handheld cold spraying device or a mechanical spraying device based on path programming, and the tool used for grinding is a small rotary grinding pen.

[0018] Furthermore, the high temperature resistant tape is a polyimide tape model 5406 produced by 3M Company of the United States; and the helium is high purity helium with a purity of 99.99%.

[0019] Furthermore, in step three, in the spraying process, when the repair powder is aluminum powder and the repaired metal part is an aluminum part, the process parameters are: gas inlet temperature is 450°C, gas pressure is 110psi, powder feeding amount is 13.45g / min, and spraying distance is 10-25mm.

[0020] The beneficial effects of the present invention are as follows: compared with traditional rigid support materials, the present invention exhibits significant technical advantages in terms of ease of operation and material adaptability. The present invention uses a gauze with excellent high temperature resistance and flexibility to closely fit the irregular surface of the hole, provide stable support during the cold spraying process, ensure uniform deposition and dense filling of metal powder, and reduce the risk of powder waste. The gauze is easy to disassemble, solving the key technical problems in the repair of through holes. It is suitable for repairing holes of various shapes and sizes, has a wide range of application value in the fields of aviation, automobiles, and construction, and provides a practical solution for the efficient and economical repair of metal structural parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the polishing process involved in step 1 of the present invention; Figure 2 This is a schematic diagram of step 2 of the present invention; Figure 3 Schematic diagram of a handheld spray gun for repairing holes in Example 1 of the present invention Figure 4 This is a photo of the hole repaired in Example 1 of the present invention; Figure 5 This is a photo of the hole repaired in Comparative Example 1 of the present invention; Figure 6 This is a photo of the holes repaired in Comparative Example 2 of the present invention. DETAILED DESCRIPTION

[0022] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0023] In order to achieve the above object, the present invention provides the following specific implementation methods: Example 1: Figure 1 , Figure 2 , Figure 3As shown, a method for repairing a through hole of a metal component by means of an easily detachable gauze comprises the following steps: Step 1: Grind and surface treat the area around the through hole on the metal part to enhance the bonding force between the repair powder and the substrate; the depth of the through hole on the metal part is 3-15mm and the radius is 3-10mm.

[0024] Among them, Figure 1 As shown, the grinding process is to grind the inner wall surfaces of the openings on both sides of the through hole into a groove with an angle of 70-80°, which is used to facilitate the deposition of repair powder; the groove treatment in the figure refers to the grinded groove.

[0025] Surface treatment is to perform sandblasting or laser scanning on the metal surface around the through hole of the metal part to remove impurities or oxide film on the surface of the metal part; Step 2: If Figure 2 As shown, a high temperature resistant tape is used to fix the flexible dense gauze on the surface of the metal component on one side of the through hole of the metal component, and the flexible dense gauze and the hole body constitute an effective deposition matrix for the repair powder; The material of the flexible dense gauze is a metal fiber material or alloy fiber material that is resistant to high temperature and has strong oxidation resistance; the thickness of the flexible dense gauze is 0.5-2mm, the wire diameter is 0.1-0.3mm, the mesh number is at least 1200 mesh, and the particle size of the repair powder is 23-50μm, ensuring that the flexible dense gauze can prevent the repair powder from being directly sprayed out of the through hole under the conditions of spraying pressure and airflow, and at the same time, facilitate the airflow to pass without causing reverse pressure, thereby ensuring that the powder in the through hole flows evenly and improving the deposition effect.

[0026] Step 3: If Figure 3 As shown, the metal part is fixed on the fixture, and the repair powder is sprayed and repaired from the through hole opening of the deposition substrate under the condition that the spray gas source is pure helium, with the spray gas inlet temperature of 400-550°C, the pressure of 110-130psi, the spray powder feeding amount of 12-15 g / min, and the spray distance of 10-25 mm; the caliber of the spray gun muzzle of the spraying equipment is not greater than the diameter of the through hole; Among them, the spraying powder material used in the spraying process is metal or metal-ceramic mixed powder; the material of the metal parts is metal and its alloy or ceramic-metal matrix composite material; the spraying equipment is a handheld cold spray device or a mechanical spray device based on path programming, and the tool used for grinding is a small rotary grinding pen.

[0027] During spray repair, the spray gun muzzle is kept at 90° to the inner wall of the through hole opening, and spray gradually in a spiral route from the inner wall edge close to the through hole to the center of the hole at a uniform speed. After 2-3 sprayings in this way, a conical protrusion with a vertex angle of 10-20° is formed in the center of the hole. The area around the protrusion is the spray dead zone, and the repair powder cannot be deposited. At this time, the protrusion is polished to be flush with the lowest point of the repair layer. After polishing, spray again in a spiral route to the center of the hole. When a protrusion is formed again, it is polished to be flush with the lowest point of the repair layer. Repeat this process until the repair is completed; Step 4: After spraying, remove the screen and polish the coating surface to ensure a smooth transition between the filler layer and the metal part surface.

[0028] Example 2: The same as Example 1, except that in step three, in the spraying process, when the repair powder is aluminum powder and the repaired metal part is an aluminum part, the process parameters are: gas inlet temperature is 450°C, gas pressure is 110psi, powder feed rate is 13.45g / min, and spraying distance is 10-25mm.

[0029] Example 3: The same as Example 1, except that the metal fiber materials used in the flexible dense gauze are stainless steel fiber, nickel fiber, and titanium fiber; the alloy fiber materials are iron-chromium-aluminum alloy fiber, constantan fiber, and Inconel alloy fiber.

[0030] The spray powder materials used in the spraying process are Al and Al alloys, Mg and Mg alloys, Cu and Cu alloys, Ti and Ti alloys, and the ceramics are Al2O3, SiC, and TiN; The materials of the metal parts are Al and Al alloys, Mg and Mg alloys, Cu and Cu alloys, Ti and Ti alloys; or the ceramic-metal matrix composite materials are Al2O3 reinforced metal matrix composite materials, SiC reinforced metal matrix composite materials, and TiN reinforced metal matrix composite materials.

[0031] Example 4: The same as Example 1, except that the high temperature resistant tape is a polyimide tape model 5406 produced by 3M Company of the United States; and the helium is high purity helium with a purity of 99.99%.

[0032] like Figure 4 , Figure 5 , Figure 6 In order to further illustrate the technical scheme and technical effects of the present invention, the following specific examples are provided: Specific example 1: like Figure 1-3 , a method for repairing a through hole of a metal component by means of an easily removable gauze, comprising the following steps: Step 1: Bevel the inner wall of the through hole of the metal aluminum part, and laser scan the metal surface around the opening twice to remove impurities or oxide film on the surface of the metal aluminum part to enhance the bonding force between the repair powder and the substrate. The depth of the through hole is 7 mm; the radius is 5 mm; the angle of the bevel is 80°; the laser scanning parameters for removing the oxide layer on the surface of the metal aluminum part are: speed 2000 mm / s, power: 100%, frequency: 70 KHz, pulse width: 500 ns, line spacing: 0.05 mm, ring spacing: 0.05 mm, light on delay: 300 μs, light off delay: 100 μs, end delay: 300 μs, corner delay: 100 μs; Step 2: Use a 1200-mesh flexible dense gauze made of stainless steel fiber material with a thickness of 0.5 mm and a wire diameter of 0.1 mm to seal the metal surface on one side of the through hole of the metal aluminum component, which serves as an effective deposition matrix for the next step of repair powder; the specific sealing method is to use 3M brand high temperature resistant tape to stick on the metal surface on one side of the through hole of the metal aluminum component.

[0033] Step 3: Fix the metal aluminum component on a special fixture, and use a specific spraying process to spray and repair the through-hole of the metal aluminum component from the front with a handheld cold spraying device to gradually fill the hole; the parameters of the spraying process are: 99.99% pure helium as the gas source; gas inlet temperature of 450 ° C; gas pressure of 110 psi; powder feeding amount of 13.45 g / min, spraying distance of 10-25 mm; the step-by-step filling of the holes is specifically as follows: the muzzle of the spray gun is kept at 90° to the inner wall of the through hole as much as possible, and spraying is performed gradually in a spiral route from the edge of the inner wall close to the through hole to the center of the hole at a uniform speed. After 2-3 sprayings in this manner, a conical protrusion with a vertex angle of 10-20° will be formed in the center of the hole, and a spraying dead zone will be formed around the protrusion, where the repair powder cannot be deposited. At this time, a small rotary grinding pen is required to grind the protrusion to be flush with the lowest point of the repair layer. After grinding, spraying is performed again in the above manner. If a protrusion is formed again, grinding is required again, and this process is repeated until the repair is completed; the repair powder is spherical Al powder with a particle size of 30-35 μm.

[0034] Step 4: After spraying, remove the screen and polish the coating surface to ensure a smooth transition between the filling layer and the surface of the metal copper part.

[0035] Repair effect Figure 4 As shown, it can be seen that the powder deposition effect is very good and the through hole can be repaired.

[0036] Specific Example 2: The metal component to be repaired is a copper component, and the material of the flexible dense gauze is titanium fiber. The method for repairing the through hole of the metal component by using the easily removable gauze comprises the following steps: Step 1: Bevel the inner wall of the through hole of the metal copper part, and laser scan the metal surface around the opening twice to remove impurities or oxide film on the surface of the metal copper part to enhance the bonding force between the repair powder and the substrate. The depth of the through hole is 10 mm; the radius is 8 mm; the angle of the bevel is 80°; the laser scanning parameters for removing the oxide layer on the surface of the metal copper part are: speed 2000 mm / s, power: 100%, frequency: 70 KHz, pulse width: 500 ns, line spacing: 0.05 mm, ring spacing: 0.05 mm, light on delay: 300 μs, light off delay: 100 μs, end delay: 300 μs, corner delay: 100 μs.

[0037] Step 2: Use a 1500 mesh flexible dense gauze made of titanium fiber material with a thickness of 1 mm and a wire diameter of 0.1 mm to seal the metal surface on one side of the through hole of the metal copper component, which serves as an effective deposition matrix for the next step of repair powder; the specific sealing method is to use 3M brand high temperature resistant tape to stick on the metal surface on one side of the through hole of the metal copper component.

[0038] Step 3: Fix the metal copper component on a special fixture, and use a specific spraying process to spray and repair the through-hole of the metal copper component from the front with a handheld cold spray device to gradually fill the hole; the parameters of the spraying process are: helium with a purity of 99.99% as the gas source; the gas inlet temperature is 500 °C; the gas pressure is 120 psi; the powder feeding amount is 15.01 g / min, and the spraying distance is 10-25 mm; the step-by-step filling of the holes is specifically as follows: the muzzle of the spray gun is kept at 90° to the inner wall of the through hole as much as possible, and spraying is performed gradually in a spiral route from the edge of the inner wall close to the through hole to the center of the hole at a uniform speed. After 2-3 sprayings in this manner, a conical protrusion with a vertex angle of 10-20° will be formed in the center of the hole, and a spraying dead zone will be formed around the protrusion, and the repair powder cannot be deposited. At this time, a small rotary grinding pen is required to grind the protrusion to be flush with the lowest point of the repair layer. After grinding, spraying is performed again in the above manner. If a protrusion is formed again, grinding is required again, and this process is repeated until the repair is completed; the repair powder uses spherical Cu powder with a particle size of 25-30μm.

[0039] Step 4: After spraying, remove the screen and polish the coating surface to ensure a smooth transition between the filling layer and the surface of the metal copper part.

[0040] Comparative Example 1: Figure 5 As shown, it is the same as the specific example 1, except that a metal plate is used to seal the through hole, that is, step 2: a metal plate is used to seal the metal surface on one side of the through hole of the metal aluminum component, which serves as an effective deposition matrix for the repair powder in the next step; Repair effect diagram Figure 5 In the figure, the repair powder is only deposited at the edge of the hole, and it is obviously not filled completely, which shows that the powder deposition effect is very poor. The specific reason is that in Comparative Example 1, a metal plate is used instead of the above-mentioned gauze as the base of the repair powder. Since the metal plate does not have a good deformation ability, and the through hole is often formed on an irregular plane or the through hole itself is irregular, it cannot form a good wrapping of the through hole, which causes the repair powder to leak from the gap between the metal plate and the edge of the through hole and cannot be effectively deposited.

[0041] In addition, the metal plate will cause too much resistance to the airflow, resulting in the airflow not being able to pass smoothly, affecting the uniformity of the spraying and the deposition quality of the powder. In addition to affecting the spraying effect, excessive airflow pressure may also cause the metal plate to deform or shift, further affecting the spraying process.

[0042] Comparative Example 2: Figure 6 As shown, it is the same as the specific example 1, except that a too thin gauze is used to block the through hole. That is, in step 2, a 1200-mesh flexible dense gauze with a thickness of 0.3 mm and a wire diameter of 0.1 mm made of stainless steel fiber material is used to seal the metal surface on one side of the through hole of the metal aluminum component, which serves as an effective deposition matrix for the next step of repair powder; the specific sealing method is to use 3M brand high temperature resistant tape to stick on the metal surface on one side of the through hole of the metal aluminum component.

[0043] Repair effect see Figure 6 It is obvious that the hole is not completely filled in the figure, and there are still blind holes. It can be seen that the deposition effect of the repair powder is not ideal. The specific reason is that the thickness of the gauze used in Control Example 2 is 0.3 mm. There is a high airflow during the spraying process, and the gauze is too thin to effectively block the repair powder, causing the powder to leak from the back of the hole, affecting the repair effect. In addition, a too thin gauze is easily damaged by impact under high spraying pressure, which affects the quality of the repair.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for repairing a through hole in a metal part by means of an easily removable gauze, characterized in that: The steps include: Step 1: Grind and surface treat the area around the through hole on the metal part to enhance the bonding strength between the repair powder and the matrix; Step 2: Use a high temperature resistant tape to fix the flexible dense gauze on the surface of the metal component on one side of the through hole of the metal component. The flexible dense gauze and the hole body constitute an effective deposition matrix for the repair powder. Step 3: Fix the metal part on the fixture, and spray the repair powder from the through hole opening of the deposition substrate under the condition that the spray gas source is pure helium, with the spray gas inlet temperature of 400-550°C, pressure of 110-130psi, spray powder feeding amount of 12-15 g / min, and spray distance of 10-25mm. The caliber of the spray gun muzzle of the spray equipment is not larger than the diameter of the through hole. During spray repair, the spray gun muzzle is kept at 90° to the inner wall of the through hole opening, and spray gradually in a spiral route from the inner wall edge close to the through hole to the center of the hole at a uniform speed. After 2-3 sprayings in this way, a conical protrusion with a vertex angle of 10-20° is formed in the center of the hole. The area around the protrusion is the spray dead zone, and the repair powder cannot be deposited. At this time, the protrusion is polished to be flush with the lowest point of the repair layer. After polishing, spray again in a spiral route to the center of the hole. When a protrusion is formed again, it is polished to be flush with the lowest point of the repair layer. Repeat this process until the repair is completed; Step 4: After spraying, remove the screen and polish the coating surface to ensure a smooth transition between the filler layer and the metal part surface.

2. The method for repairing a through hole of a metal component by means of an easily removable gauze as claimed in claim 1, characterized in that: In step 1, the grinding process is to grind the inner wall surfaces of the openings on both sides of the through hole into a groove with an angle of 70-80 degrees, so as to facilitate the deposition of the repair powder; The surface treatment is to perform sandblasting or laser scanning on the metal surface around the through hole of the metal component to remove impurities or oxide film on the surface of the metal component.

3. The method for repairing a through hole of a metal component by means of an easily removable gauze as claimed in claim 1, characterized in that: In step 2, the material of the flexible dense gauze is a metal fiber material or alloy fiber material that is resistant to high temperature and has strong oxidation resistance; the thickness of the flexible dense gauze is 0.5-2mm, the wire diameter is 0.1-0.3mm, the mesh number is at least 1200 mesh, and the particle size of the repair powder is 23-50μm, ensuring that the flexible dense gauze can prevent the repair powder from being directly sprayed out of the through hole under the conditions of spraying pressure and airflow, and at the same time, facilitate the airflow to pass through without causing reverse pressure, thereby ensuring that the powder in the through hole flows evenly and improving the deposition effect.

4. The method for repairing a through hole of a metal component by means of an easily removable gauze as claimed in claim 3, characterized in that: The metal fiber material is stainless steel fiber, nickel fiber, titanium fiber; the alloy fiber material is iron-chromium-aluminum alloy fiber, constantan fiber, Inconel alloy fiber.

5. The method for repairing a through hole of a metal component by means of an easily removable gauze as claimed in claim 1, characterized in that: In step three, the spraying powder material used in the spraying process is metal or metal-ceramic mixed powder; the metal is Al and Al alloys, Mg and Mg alloys, Cu and Cu alloys, Ti and Ti alloys, and the ceramic is Al2O3, SiC, TiN.

6. The method for repairing a through hole of a metal component by means of an easily removable gauze as claimed in claim 1, characterized in that: The material of the metal component is metal and its alloy or ceramic-metal matrix composite material; the metal and alloy are Al and Al alloy, Mg and Mg alloy, Cu and Cu alloy, Ti and Ti alloy; the ceramic-metal matrix composite material is Al2O3 reinforced metal matrix composite material, SiC reinforced metal matrix composite material, TiN reinforced metal matrix composite material.

7. The method for repairing a through hole of a metal component by means of an easily removable gauze as claimed in claim 1, characterized in that: The through hole on the metal component has a depth of 3-15 mm and a radius of 3-10 mm.

8. The method for repairing a through hole of a metal component by means of an easily removable gauze as claimed in claim 1, characterized in that: The spraying equipment is a handheld cold spraying device or a mechanical spraying device based on path programming, and the tool used for grinding is a small rotary grinding pen.

9. The method for repairing a through hole of a metal component by means of an easily removable gauze as claimed in claim 1, characterized in that: The high temperature resistant tape is a polyimide tape of model 5406 produced by 3M Company of the United States; the helium is high purity helium with a purity of 99.99%.

10. The method for repairing a through hole of a metal component by means of an easily detachable gauze according to any one of claims 1 to 9, characterized in that: In step three, in the spraying process, when the repair powder is aluminum powder and the repaired metal part is an aluminum part, the process parameters are: gas inlet temperature is 450°C, gas pressure is 110psi, powder feeding amount is 13.45g / min, and spraying distance is 10-25mm.

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