A method for stripping an EB-PVD ceramic layer from a guide vane without damaging the metal layer

Abstract

The application discloses an EB-PVD ceramic layer peeling method of a guide vane without damaging a metal layer, and belongs to the technical field of thermal barrier coating repair of aero-engine and gas turbine turbine vane, wherein first, the non-coating area of a workpiece is protected, and the workpiece is fixed on a peeling machine to ensure that the non-coating area is not peeled; the peeling of the ceramic is realized through the interaction between abrasive particles and the ceramic layer; only the ceramic powder generated by grinding exists, the ceramic powder does not pollute the environment, is safe and environmentally friendly, and can realize non-damage control of the metal bottom layer; the problems, such as the local incomplete problem of the metal bottom layer, the profile and wall thickness out-of-tolerance problem caused by the damage of the base body part, and the turbine vane gas film hole diameter out-of-tolerance problem caused by the erosion effect, which cannot be solved by the dry sandblasting process, are solved; the problem that the ceramic layer cannot be effectively removed in the throat shielding area existing in the pulse water jet is solved; and the problems, such as the complex process, environmental pollution and safety hidden danger existing in the pressurized alkali boiling process, are solved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of turbine blade thermal barrier coating repair of aero-engine and gas turbine, and particularly relates to a method for stripping EB-PVD ceramic layer of a guide vane without damaging the metal layer. BACKGROUND

[0002] With the continuous development of aero-engine and gas turbine technology, the working temperature of turbine components is getting higher and higher, and the working environment is getting more and more harsh. However, the working temperature that the best high-temperature resistant metal material can withstand for a long time is only about 1100℃, while the current advanced turbine inlet temperature is as high as 1700℃. Through the application of film cooling technology, the working temperature of high-temperature components such as turbine blades is close to 1200℃. In order to effectively solve the technical problems of service life of high-temperature components, the most effective, economic and feasible technical means is to prepare a thermal barrier coating with high-temperature oxidation resistance, high-temperature corrosion resistance and high thermal insulation function on the surface of the workpiece, so as to reduce the service temperature of high-temperature components and improve their service life.

[0003] The thermal barrier coating is a composite coating formed by ceramic material with the advantages of high-temperature resistance, low thermal conductivity and corrosion resistance and metal bonding layer, which can reduce the temperature of the surface of the metal matrix material and improve the high-temperature resistance and oxidation corrosion resistance of the matrix material. The thermal barrier coating is widely used on the blades of aero-engine and gas turbine, and by reducing the working temperature of the blade surface, the service life of the blade is improved. The thermal barrier coating mainly includes three structural forms, namely double-layer, multi-layer and gradient structure; among them, the double-layer structure thermal barrier coating is the most widely used, which mainly uses electron beam physical vapor deposition technology (EB-PVD) for ceramic coating. The service environment of the thermal barrier coating is very complex and harsh, including high temperature, high pressure, corrosion, wear, impact of foreign objects, etc. During the use or preparation of the coating, the nucleation and expansion of cracks will cause a large amount of bending and cracking in the coating, which will eventually lead to local peeling of the coating. The peeled thermal barrier coating faces the problem of coating stripping and recoating.

[0004] Existing EB-PVD ceramic layer removal technologies mainly include dry sandblasting, pulsed water jet technology, and pressurized alkaline boiling. However, these technologies all have their own defects and problems, affecting the mature application of EB-PVD ceramic layer removal technology. For example, the dry sandblasting process results in incomplete metal substrates after sandblasting, damage to the turbine blade substrate causing deviations in profile and wall thickness, and the erosion effect of dry sandblasting can also cause deviations in the diameter of the turbine blade film pores. When removing the ceramic layer using pulsed water jet technology, the impact of the pulsed water jet on the blade area can also cause localized bulging or peeling of the metal substrate. In addition, the pulsed water jet can only achieve linear action and cannot effectively affect the throat area of ​​the turbine guide vane, resulting in ineffective removal of the ceramic layer in the turbine guide vane throat area, which has significant application limitations. The pressurized alkaline boiling process for removing the ceramic layer is complex, pollutes the environment with alkaline solutions during removal, and involves high pressure in the high-pressure reactor, posing significant safety hazards and environmental impacts. Therefore, it is essential to develop a new EB-PVD ceramic layer peeling process that is simpler, safer, and more environmentally friendly to meet the urgent need for engine turbine blade thermal barrier coating repair technology. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, the present invention aims to provide an EB-PVD ceramic layer peeling method for non-destructive metal layer of guide vanes, so as to solve the technical problems of existing peeling techniques damaging the blade substrate and metal layer, failing to effectively remove the ceramic layer in the blade throat area, and having safety hazards and environmental impacts.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] A method for non-destructive removal of the EB-PVD ceramic layer from the metal layer of a guide vane includes the following steps:

[0008] Protect the uncoated areas of the workpiece and secure the workpiece to the peeling machine;

[0009] Set the operating parameters of the peeling machine and use abrasive particles to peel off the protected workpiece;

[0010] The workpiece after peeling is cleaned to complete the ceramic peeling process.

[0011] Preferably, when fixing the workpiece, the upper and lower edge plates of the workpiece are placed in a horizontal direction.

[0012] Preferably, the abrasive grains are Al2O3 abrasive grains with a diameter of 3-4 mm.

[0013] Preferably, the operating parameters of the peeling machine include: spindle rotation speed, drum rotation speed, workpiece downward insertion depth, frequency of forward and reverse rotation, and peeling time.

[0014] Preferably, the main shaft rotation rate is 2-4 rpm; and the drum rotation rate is 4-6 rpm.

[0015] Preferably, the workpiece extends downward by a depth of G+40mm-G+50mm, wherein G represents the height of the workpiece ceramic layer to be peeled area.

[0016] Preferably, the forward and reverse alternating frequency is 15min / time-20min / time.

[0017] Preferably, the peeling time is determined according to the maximum thickness of the ceramic layer, specifically: peeling time = coating thickness (μm) x 0.3 (min / μm).

[0018] Preferably, compressed air is used to clean the workpiece after peeling.

[0019] Preferably, a fixed tool is used to protect the non-coating area of the workpiece, and the workpiece is fixed on the peeling machine, the tool includes a first fixing box, a second fixing box, a bolt and a nut, the first fixing box and the second fixing box are respectively arranged at both ends of the workpiece and wrap the non-coating area of the workpiece, the end of the second fixing box is provided with the bolt and the nut, and is fixed on the peeling machine through the bolt and the nut, and the outer sides of the first fixing box and the second fixing box are respectively provided with a plurality of nuts.

[0020] Compared with the prior art, the present application has the following beneficial effects:

[0021] The disclosed guide vane EB-PVD ceramic layer peeling method without damaging the metal layer protects the non-coating area of the workpiece and fixes the workpiece on the peeling machine, ensuring that the non-coating area is not peeled, and the peeling of the ceramic is realized through the interaction between the abrasive particles and the ceramic layer, only the ceramic powder generated by grinding exists, and the ceramic powder does not pollute the environment, is safe and environmentally friendly, can realize non-damage control of the metal bottom layer, and completely solves the problems of incomplete metal bottom layer, type surface and wall thickness exceeding the tolerance caused by damage to the base part, and hole diameter exceeding the tolerance of the turbine blade gas film hole caused by erosion, etc. The problem of the throat shielding area of the pulse water jet cannot effectively remove the ceramic layer is completely solved. The problems of complex process, environmental pollution and safety hazards existing in the pressurized alkali cooking process are completely solved.

[0022] Further, when the workpiece is fixed, the upper and lower edge plates of the workpiece are placed in a horizontal direction, so that the grinding force on the edge plate part is minimized and the removal amount is reduced. The design concept perfectly matches the phenomenon of thin shielding area thickness existing when the guide vane EB-PVD ceramic layer is coated, the removal amount of the thicker area is large, and the removal amount of the thinner area is small, realizing the equal proportion peeling of the thin and thick areas of the ceramic layer, and the process adaptability is good. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 Typical profile of a guide vane

[0024] Figure 2 Schematic diagram of interaction between abrasive particles and guide vanes

[0025] Figure 3 Microstructure of thermal barrier coating before ceramic layer peeling

[0026] Figure 4 Microstructure after treatment in Example 1 of the present application

[0027] Figure 5 Microstructure after treatment in Example 2 of the present application

[0028] Figure 6 Microstructure after treatment in Example 3 of the present application

[0029] Figure 7 Schematic diagram of a fixed tooling structure of the present application

[0030] Figure 8 Flow chart of the method of the present application DETAILED DESCRIPTION

[0031] In order to make the personnel in the technical field better understand the present application scheme, the technical scheme in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without making creative efforts should belong to the scope of protection of the present application.

[0032] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0033] The present application will be further described in detail below in combination with the drawings:

[0034] In order to solve various problems existing in the prior ceramic layer stripping technology, the application provides an EB-PVD ceramic layer stripping method for a guide vane without damaging the metal layer, which fully utilizes the columnar crystal structure and the large brittleness of the EB-PVD ceramic layer, realizes the stripping of the EB-PVD ceramic layer through the mutual grinding between the abrasive grains and the ceramic layer, ensures the effective removal of the ceramic layer in the shielding area and the non-shielding area, and realizes the non-damage control of the metal layer through the process parameters set by the application, thereby breaking through the repair technology of the thermal barrier coating of the turbine vane and providing technical support for the repair and service life extension of the turbine part of the aero-engine.

[0035] Referring to Figure 8 The application discloses an EB-PVD ceramic layer stripping method for a guide vane without damaging the metal layer, which comprises the following steps:

[0036] The non-coating area of the workpiece is protected, and the workpiece is fixed on the stripping machine;

[0037] The running parameters of the stripping machine are set, and the protected workpiece is stripped by using abrasive grains;

[0038] The stripped workpiece is cleaned, and the ceramic stripping process is completed.

[0039] The non-coating area of the workpiece is protected, and the workpiece is fixed on the stripping machine, so as to prevent the abrasive grains from grinding the non-coating area. The concept is perfectly matched with the phenomenon that the shielding area is thin during the EB-PVD ceramic layer coating of the guide vane. The removal amount of the thicker area is large, and the removal amount of the thinner area is small, so that the ceramic layer in the thin area and the thick area is stripped at the same ratio. The process adaptability is good. The ceramic is stripped through the mutual action between the abrasive grains and the ceramic layer. Only the ceramic powder generated by grinding exists, and the ceramic powder does not pollute the environment and is safe and environmentally friendly. The non-damage control of the metal bottom layer is realized. The problems, such as the local incomplete problem of the metal bottom layer, the profile and wall thickness out-of-tolerance problem caused by the damage of the base part, and the turbine vane gas film hole diameter out-of-tolerance problem caused by the erosion effect, which cannot be solved by the dry sandblasting process, are completely solved. The problem that the ceramic layer in the throat shielding area cannot be effectively removed by the pulse water jet is completely solved. The problems, such as the complex process, environmental pollution and safety hidden danger, which exist in the pressurized alkali cooking process, are completely solved.

[0040] In some embodiments, when the workpiece is fixed, the upper and lower edge plates of the workpiece are placed in a horizontal direction, so that the grinding force on the edge plate part is minimized and the removal amount is reduced.

[0041] In some embodiments, the abrasive grains are Al2O3 abrasive grains with a diameter of 3-4 mm.

[0042] In some embodiments, the running parameters of the stripping machine include the rotation rate of the main shaft, the rotation rate of the roller, the downward extension depth of the workpiece, the forward and reverse alternating frequency and the stripping time.

[0043] As a preferred solution, the main shaft rotation rate is 2-4 rpm; the drum rotation rate is 4-6 rpm.

[0044] As a preferred solution, the workpiece downward extension depth is G+40mm-G+50mm, wherein G represents the height of the workpiece ceramic layer to be peeled area.

[0045] As a preferred solution, the forward and reverse alternating frequency is 15min / time-20min / time.

[0046] As a preferred solution, the peeling time is determined according to the maximum thickness of the ceramic layer, specifically: peeling time = coating thickness (μm) x 0.3 (min / μm).

[0047] In some embodiments, referring to Figure 7 , a fixed tool is used to protect the non-coating area of the workpiece, and the workpiece is fixed on the peeling machine, the tool includes a first fixing box 1, a second fixing box 2, a bolt 3 and a nut 4, the first fixing box 1 and the second fixing box 2 are respectively arranged at both ends of the workpiece and wrap the non-coating area of the workpiece, the second fixing box 2 end is provided with the bolt 3 and the nut 4, and is fixed on the peeling machine through the bolt 3 and the nut 4, and the outer sides of the first fixing box 1 and the second fixing box 2 are respectively provided with a plurality of nuts 4.

[0048] In some embodiments, the present application is a kind of EB-PVD ceramic layer peeling method of guide vane without damaging metal layer, including the following processes: first, the guide vane to be removed ceramic layer is clamped on the tool, the tool effectively protects the non-coating area of the guide vane, prevents the grinding of abrasive particles on the non-coating area, and ensures that the upper and lower edge plates of the multi-union guide vane are placed in a horizontal direction during clamping to minimize the grinding force on the edge plate part. Secondly, the guide vane equipped with the tool is clamped to the rotating spindle of the grinding and finishing machine, the part is extended downward into the rotating bin filled with abrasive particles, and ceramic layer peeling treatment is carried out according to the set process parameters. Finally, the part is removed from the rotating spindle, the tool is disassembled, the part surface is cleaned with flowing tap water, and compressed air is used to dry, and the EB-PVD ceramic layer peeling is completed.

[0049] In some embodiments, the specific steps of the present application are as follows:

[0050] 1) Workpiece clamping before ceramic layer peeling. Referring to Figure 1 , Figure 2 and Figure 7Before the ceramic layer is stripped, the guide vane to be removed of the ceramic layer is clamped on the tooling, the tooling effectively protects the non-coating area of the guide vane, prevents the grinding of abrasive particles on the non-coating area, and is bolted to the main shaft of the equipment to ensure firm connection; at the same time, since the EB-PVD ceramic layer at the edge plate part has basically no binding force, the upper and lower edge plates of the multi-union guide vane are placed in a horizontal direction during clamping, so that the grinding force on the edge plate part is minimized.

[0051] 2) Ceramic layer stripping abrasive preparation. Select Al2O3 abrasive particles of the required size for stripping, with a diameter of 3-4 mm, and screen and clean the abrasive particles.

[0052] 3) Stripping process parameter setting and trial operation. Set the main shaft rotation rate on the stripping machine to 2-4 rpm, the drum rotation rate to 4-6 rpm, the part downward extension depth to G+40mm-G+50mm (G represents the height of the ceramic layer to be stripped of the part), and the positive and negative rotation alternating frequency to 15min / time-20min / time, etc. The stripping time is determined according to the maximum thickness of the ceramic layer, and the stripping time = coating thickness x 0.3min / μm. The maximum thickness of most EB-PVD ceramic layers is 150-200μm, and the stripping time is 45-60min. The process parameters are set and simulated trial operation is carried out on the stripping machine to verify whether the process parameter setting is correct.

[0053] 4) Ceramic layer stripping treatment. After the stripping process parameters are set and trial operation is carried out, the stripping machine is operated in automatic mode for ceramic layer stripping treatment of the workpiece to be stripped of the ceramic layer.

[0054] 5) Post-stripping treatment. After the ceramic layer stripping treatment, the ceramic layer stripping workpiece and the tooling are disassembled from the main shaft of the stripping machine, the tooling is removed, compressed air is used to clean the surface of the workpiece after the ceramic layer stripping is completed, and the ceramic stripping treatment is completed.

[0055] Example 1

[0056] The specific steps of the EB-PVD ceramic layer stripping process method of the guide vane metal layer without damage according to the application are as follows:

[0057] 1) Workpiece clamping before ceramic layer stripping. Before the ceramic layer is stripped, the guide vane to be removed of the ceramic layer is clamped on the tooling, the tooling effectively protects the non-coating area of the guide vane, prevents the grinding of abrasive particles on the non-coating area, and is bolted to the main shaft of the equipment to ensure firm connection; at the same time, since the EB-PVD ceramic layer at the edge plate part has basically no binding force, the upper and lower edge plates of the multi-union guide vane are placed in a horizontal direction during clamping, so that the grinding force on the edge plate part is minimized.

[0058] 2) Ceramic layer peeling abrasive particle preparation. Select Al2O3 abrasive particles of the required size for peeling, the abrasive particle diameter is 3 mm, and the abrasive particles are screened and cleaned.

[0059] 3) Peeling process parameter setting and trial run. The spindle rotation rate is set to 4 rpm, the drum rotation rate is set to 4 rpm, the part is extended downward by 80+40 mm (G represents the height of the ceramic layer of the part to be peeled), the positive and negative rotation alternating frequency is 15 min / time, the peeling time is determined according to the maximum thickness of the ceramic layer, the peeling time = coating thickness (μm) x 0.3 (min / μm) (time tolerance ± 5 min), the ceramic thickness of this embodiment is 150 μm, the peeling time is determined to be 45±5 min, and the process parameters are set on the peeling machine for simulation trial run to verify whether the process parameter setting is correct.

[0060] 4) Ceramic layer peeling treatment. After the peeling process parameters are set and trial run, the peeling machine equipment is operated in automatic mode, and the ceramic layer peeling treatment is performed on the workpiece to be peeled.

[0061] 5) Post-peeling treatment. After the ceramic layer peeling treatment, the ceramic layer peeling workpiece and the tooling are disassembled from the spindle of the peeling machine, the tooling is removed, compressed air is used to clean the surface of the workpiece after the ceramic layer peeling is completed, and the ceramic peeling treatment is completed.

[0062] Results: The thickness of the metal layer and the ceramic layer before and after the ceramic layer peeling of the double guide vane of scheme 1 is compared, the ceramic layer is effectively peeled, the thickness becomes 0 μm, and the thickness of the metal bottom layer does not change, which shows that the EB-PVD ceramic layer peeling of the guide vane metal layer without damage is realized by using the patent.

[0063] The microstructure of the ceramic layer after peeling is shown in Figure 4 The microstructure of the ceramic layer before peeling is compared. Figure 3 It can be seen that the ceramic layer is effectively peeled, and the microstructure and thickness of the metal layer do not change, which shows that the EB-PVD ceramic layer peeling of the guide vane metal layer without damage is realized by using the patent.

[0064] Example 2

[0065] The specific steps of the EB-PVD ceramic layer peeling process method of the guide vane metal layer without damage of the present application are as follows:

[0066] 1) Workpiece clamping before ceramic layer stripping. Before the ceramic layer is stripped, the guide vane to be removed from the ceramic layer is clamped on the tool, the tool effectively protects the non-coated area of the guide vane, prevents the grinding of abrasive particles on the non-coated area, and is bolted to the main shaft of the equipment to ensure firm connection; at the same time, since the EB-PVD ceramic layer at the edge plate part has basically no bonding force, the upper and lower edge plates of the multi-union guide vane are placed in a horizontal direction during clamping to minimize the grinding force on the edge plate part.

[0067] 2) Abrasive particle preparation for ceramic layer stripping. Select Al2O3 abrasive particles of the required size for stripping, with a diameter of 3 mm, and screen and clean the abrasive particles.

[0068] 3) Stripping process parameter setting and trial run. Set the main shaft rotation rate to 3 rpm, the drum rotation rate to 5 rpm, the part downward extension depth to 80+45 mm (G represents the height of the ceramic layer to be stripped), the positive and negative rotation alternating frequency to 18 min / time, and the stripping time is determined according to the maximum thickness of the ceramic layer, Stripping time = coating thickness (μm) x 0.3 (min / μm) (time tolerance ± 5 min), the ceramic thickness of this embodiment is 180 μm, the stripping time is determined to be 54 ± 5 min, and the process parameters are set for simulation trial run on the stripping machine to verify whether the process parameter setting is correct.

[0069] 4) Ceramic layer stripping treatment. After setting and trial running the stripping process parameters, select the automatic mode for the stripping machine equipment operation mode, and perform ceramic layer stripping treatment on the workpiece to be stripped from the ceramic layer.

[0070] 5) Post-stripping treatment. After the ceramic layer stripping treatment, the ceramic layer stripping workpiece and tool are disassembled from the main shaft of the stripping machine, the tool is removed, compressed air is used to clean the surface of the workpiece after the ceramic layer stripping is completed, and the ceramic stripping treatment is completed.

[0071] Results: The thickness comparison of the metal layer and the ceramic layer before and after the ceramic layer stripping of the double-union guide vane of scheme 2 shows that the ceramic layer has been effectively stripped, the thickness has become 0 μm, and the metal bottom layer thickness has not changed, which indicates that the EB-PVD ceramic layer stripping of the guide vane metal layer without damage is realized by using the present patent.

[0072] The microstructure of the ceramic layer after stripping is shown in Figure 5 The microstructure of the ceramic layer after stripping is shown in Figure 3 The microstructure of the ceramic layer after stripping is shown in

[0073] Example 3

[0074] The specific steps of the EB-PVD ceramic layer stripping process method without damaging the metal layer of the guide vane according to the application are as follows:

[0075] 1) Workpiece clamping before ceramic layer stripping. Before the ceramic layer is stripped, the guide vane to be removed of the ceramic layer is clamped on the tooling, the tooling effectively protects the non-coating area of the guide vane from grinding by the abrasive particles, and is bolted to the main shaft of the equipment to ensure firm connection; at the same time, since the EB-PVD ceramic layer on the rim plate part has basically no binding force, the upper and lower rim plates of the multi-connection guide vane are placed in a horizontal direction during clamping to minimize the grinding force on the rim plate part.

[0076] 2) Abrasive particle preparation for ceramic layer stripping. Al2O3 abrasive particles with a diameter of 3 mm are selected for stripping, and the abrasive particles are sieved and cleaned.

[0077] 3) Stripping process parameter setting and trial operation. The main shaft rotation rate is set to 2 rpm, the drum rotation rate is set to 6 rpm, the part is extended downward by a depth of 80+50 mm (G represents the height of the ceramic layer to be stripped of the part), the positive and negative rotation alternating frequency is set to 20 min / once, and the stripping time is determined according to the maximum thickness of the ceramic layer, the stripping time = coating thickness (μm) x 0.3 (min / μm) (time tolerance ±5 min). In this embodiment, the ceramic thickness is 200 μm, the stripping time is determined to be 60±5 min, and the simulation trial operation is performed on the stripping machine according to the set process parameters to verify whether the process parameter setting is correct.

[0078] 4) Ceramic layer stripping treatment. After the stripping process parameters are set and the trial operation is performed, the stripping machine is operated in automatic mode to strip the ceramic layer of the workpiece to be stripped of the ceramic layer.

[0079] 5) Post-stripping treatment. After the ceramic layer stripping treatment, the ceramic layer stripping workpiece and the tooling are detached from the main shaft of the stripping machine, the tooling is removed, compressed air is used to clean the surface of the workpiece after the ceramic layer stripping is completed, and the ceramic stripping treatment is completed.

[0080] Results: The thickness comparison of the metal layer and the ceramic layer before and after the ceramic layer stripping of the double-connection guide vane of scheme 3 shows that the ceramic layer is effectively stripped, the thickness becomes 0 μm, and the thickness of the metal bottom layer basically does not change, which indicates that the EB-PVD ceramic layer stripping of the guide vane metal layer without damage is realized by using the patent.

[0081] The microstructure of the ceramic layer after stripping is shown in Figure 6 and Figure 3The contrast of the microstructure of the thermal barrier coating before the ceramic layer is peeled off can show that the ceramic layer is effectively peeled off, and the microstructure and thickness of the metal layer are not changed, which shows that the EB-PVD ceramic layer peeling off of the metal layer of the guide vane is realized by using the patent.

[0082] The above is only used for illustrating the technical idea of the present application, and cannot limit the protection scope of the present application. Any modification made according to the technical idea of the present application on the basis of the technical scheme falls into the protection scope of the claims of the present application.

Claims

1. A method of delaminating an EB-PVD ceramic layer from a guide vane without damaging the metal layer, characterized in that It comprises the following steps: Protecting the non-coating area of the workpiece and fixing the workpiece on the stripping machine; when fixing the workpiece, the upper and lower edge plates of the workpiece are placed horizontally; Setting the operation parameters of the stripping machine and using abrasive particles to strip the protected workpiece; the abrasive particles are Al2O3 abrasive particles with a diameter of 3-4 mm; the operation parameters of the stripping machine include the rotation rate of the main shaft, the rotation rate of the drum, the downward extension depth of the workpiece, the frequency of forward and reverse rotation alternation, and the stripping time; the rotation rate of the main shaft is 2-4 rpm; the rotation rate of the drum is 4-6 rpm; the downward extension depth of the workpiece is G+40-50 mm, where G represents the height of the ceramic layer to be stripped; the frequency of forward and reverse rotation alternation is 15-20 min / time; the stripping time is determined according to the maximum thickness of the ceramic layer, specifically: stripping time = coating thickness μm x 0.3 min / μm; Cleaning the stripped workpiece to complete the ceramic stripping process.

2. The method of claim 1, wherein the ceramic layer is an EB-PVD ceramic layer of a guide vane. Cleaning the stripped workpiece with compressed air.

3. The method of claim 1, wherein the ceramic layer is an EB-PVD ceramic layer of a guide vane. A fixed tool is used to protect the non-coating area of the workpiece, and the workpiece is fixed on the stripping machine; the tool comprises a first fixing box (1), a second fixing box (2), a bolt (3), and a nut (4); the first fixing box (1) and the second fixing box (2) are respectively arranged at both ends of the workpiece and wrap the non-coating area of the workpiece; the end of the second fixing box (2) is provided with the bolt (3) and the nut (4), and is fixed on the stripping machine through the bolt (3) and the nut (4); and a plurality of nuts (4) are further arranged on the outer sides of the first fixing box (1) and the second fixing box (2).

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