A method for plating wear-resistant coating on dual-journal adjustable stator blades of an aero-engine

Abstract

The present invention relates to the technical field of wear-resistant coating plating of aircraft engine parts, and specifically to a wear-resistant coating plating method for dual-journal adjustable stator blades of aircraft engines, which includes the design and use of a special plating device, an innovative spraying process, and coating post-processing. The special device consists of a cylinder, a cylinder cover, a long sleeve, a short sleeve, a clamp, etc., to achieve precise protection of non-coated areas; the spraying process ensures coating performance by controlling sand blowing, spraying, and cooling parameters, with a coating thickness of 0.2~0.3mm and a hardness value of ≥950HV0.3; the post-processing adopts an external circular grinding machine for processing, and the surface roughness reaches Ra0.4μm. The present invention can efficiently and accurately complete the plating of narrow areas, significantly improve the wear resistance and service life of dual-journal adjustable stator blades of aircraft engines, and meet the harsh working conditions and mass production requirements of aircraft engines.

Description

Technical Field

[0001] The invention belongs to the technical field of wear-resistant coating plating of aircraft engine parts, and particularly relates to a wear-resistant coating plating method for dual-journal adjustable stator blades of an aircraft engine. Background Art

[0002] Aircraft engines, known as the "crown jewel of industry," are the heart of aircraft, and their performance directly impacts aircraft efficiency and reliability. As a key component of aircraft engines, adjustable stator blades optimize the airflow angle of attack by dynamically adjusting their angle, significantly improving engine efficiency and surge margin, thereby achieving high efficiency and stable operation over a wide range of operating conditions. However, during operation, the journal and shoulder areas of the adjustable stator blades form friction pairs with the metal bushings of the casing, subjecting them to long-term high loads and high wear conditions. Therefore, they require strengthening treatment to improve wear resistance, extend service life, and ensure reliability.

[0003] Coating technology is an economical and efficient surface enhancement method that can impart specialized features such as wear resistance, oxidation resistance, and low emissivity to components. It also offers the advantage of strong adaptability to complex component surfaces. Currently, common wear-resistant coating deposition methods include physical vapor deposition, chemical vapor deposition, laser cladding, electroplating and electroless plating, sol-gel methods, and thermal spraying. However, these methods all have limitations in practical application. Although physical vapor deposition has a low process temperature and high hardness, it is subject to the influence of internal stress in the coating, and the coating thickness is relatively thin, usually around 10μm, which makes it difficult to meet the needs of high-load and high-wear working conditions. It is often used in the fields of surface hardening of cutting tools and molds, watch decoration, etc.; although chemical vapor deposition has a dense coating and good high-temperature stability, its process temperature is high, the deposition rate is slow, and the by-product treatment is complicated. It is often used for diamond coating of cutting tools and corrosion-resistant layer plating of semiconductor equipment; although laser cladding has high bonding strength, it has a large heat-affected zone and is not suitable for precision machining of small-sized parts. It is often used in the fields of wear-resistant repair of oil drill pipes and strengthening of high-end valve sealing surfaces; electroplating and chemical plating have low costs and are suitable for mass production, but have low hardness, high environmental pressure and weak bonding strength. They are often used in the fields of hydraulic rod chrome plating and automotive piston ring surface treatment; although the sol-gel method has the characteristics of controllable nanostructure, the coating is brittle, the process cycle is long, and industrialization is difficult, and it is generally used for anti-scratch coating plating of optical glass.

[0004] Thermal spraying technology has been widely used in the preparation of surface coatings for aircraft engine components due to its high deposition rate, wide material selection, and flexible process. WC-Co cermet coatings, composed of hard WC particles and a tough Co binder phase, combine high hardness, wear resistance, and impact resistance, making them ideal wear-resistant coating materials. However, existing thermal spray processes such as plasma spraying, detonation spraying, and supersonic oxygen fuel (HVOF) spraying also have their own shortcomings. While plasma spraying offers a fast deposition rate, the coating has high porosity, which can easily lead to the decomposition of WC into W2C and free carbon, thus reducing hardness. Detonation spraying introduces compressive stress through high-velocity impact, which can improve part fatigue resistance, but the single spraying area is small and the deposition rate is slow. While HVOF spraying combines the advantages of low temperature, high speed, and low WC decomposition, the high-temperature, high-velocity flame causes significant erosion of non-sprayed areas during the spraying process. Existing protective measures, such as high-temperature pressure-sensitive adhesive tape and high-temperature resistant adhesive putty, are easily ineffective due to high-temperature combustion during spraying, making it difficult to effectively protect non-coated areas. Furthermore, the journal and shoulder areas of dual-journal adjustable stator blades are relatively small, making traditional spray coating processes difficult to meet the demanding service conditions and mass production requirements of aircraft engines. Therefore, effectively protecting the non-coated areas and innovating the spray coating process to achieve high-quality coatings in confined areas of small parts have become urgent technical challenges. Summary of the Invention

[0005] In view of the problems of failure of protection of non-coated areas, insufficient coating performance and low process efficiency in the prior art during the plating of wear-resistant coatings on the journals and shoulders of dual-neck adjustable stator blades of aircraft engines, the present invention proposes a plating method for wear-resistant coatings on dual-neck adjustable stator blades of aircraft engines. By combining a special plating device with a supersonic flame spraying process, efficient and precise plating of narrow areas of dual-neck adjustable stator blades is achieved, meeting the requirements of efficient and high-quality preparation of wear-resistant coatings on the journals and shoulders of dual-neck adjustable stator blades of aircraft engines, while achieving long service life and high reliability of the coating.

[0006] The technical solution of the present invention is:

[0007] A method for coating a wear-resistant coating on an aero-engine dual-journal adjustable stator blade comprises the following steps:

[0008] Step 1: Design a coating device and install the double-journal adjustable stator blade on a dedicated coating device to protect the non-coated area of ​​the blade. The coating area includes the blade journal and blade shoulder areas.

[0009] The plating device is composed of a cylinder, a cylinder cover a, a long sleeve, a cylinder cover b, a short sleeve, a clip, a pin, a cap nut, a nut and a bolt, wherein:

[0010] When plating the shaft neck of a blade, the blade is installed in a barrel and positioned using the shoulder surface and inner hole of the barrel; the barrel cover b is screwed into the threaded end of the barrel to protect the upper shoulder surface of the blade; at least two clips are fixed to the shaft diameter of the blade using nuts and bolts to protect the non-spraying area in the middle of the shaft diameter; a short sleeve is installed on the upper end of the blade; and the plating device is connected to the spraying equipment using a pin and a cap nut.

[0011] When plating the blade shoulder, remove the barrel cover b, short sleeve and clip, screw the barrel cover a into the threaded end of the barrel, and install the long sleeve into the upper end of the blade;

[0012] Step 2: coating the coating area with a WC-Co wear-resistant coating using a kerosene-oxygen mixed fuel supersonic flame spraying process; the coating thickness is 0.2-0.3 mm;

[0013] Step 3: Grind the surface of the sprayed coating to make the coating surface have a uniform metallic luster and a roughness Ra < 0.6 μm;

[0014] The components of the WC-Co wear-resistant coating powder include, by weight percentage, Co: 15.0-18.0wt%, C: 4.5-5.6wt%, Fe not more than 2.0wt%, W not less than 76.0wt%, and the total amount of other impurities not more than 1.0wt%. The powder particle size distribution range must meet the following requirements: particle size of 53μm and above is not more than 2.0wt%, particle size of 45μm-53μm is not more than 20.0wt%, particle size of 10μm-45μm is not less than 75.0wt%, and particle size of 10μm and below is not more than 3.0wt%.

[0015] Furthermore, in the above-mentioned method for coating a wear-resistant coating on a dual-journal adjustable stator blade of an aero-engine, the spraying process in step 2 specifically includes:

[0016] Step 2.1, dry sandblasting treatment is performed on the plated area, wherein the sandblasting is performed using a sandblasting gun with a nozzle diameter of 7.0-8.5 mm, 60# white corundum sand, a sandblasting distance of 140-180 mm, and a compressed air pressure of 0.25-0.35 MPa; wherein the sandblasting angle for the blade shaft neck is 55°-85°, and the sandblasting angle for the blade shaft shoulder is 15°-45°; the turntable speed is 30-40 rpm, and the sandblasting gun movement speed is 5 mm / s;

[0017] Step 2.2, fixing the sandblasted blades and the coating device on a ten-station turntable to achieve simultaneous spraying of 10 blades;

[0018] Step 2.3, using a kerosene-oxygen mixed fuel supersonic flame spraying process to coat a WC-Co wear-resistant coating, the coating parameters include: barrel length 101.6 mm, spraying distance 350-380 mm, powder feed rate 80-90 g / min, oxygen flow rate 800-880 NLPM, kerosene flow rate 18-22 L / h, argon carrier gas, carrier gas flow rate 9.0-10.0 NLPM, part rotation speed 540-660 rpm, and spray gun movement speed 90-110 mm / s; wherein, the spray angle for the blade journal portion is 80°-90°, and the spray angle for the blade shoulder portion is 65-75°;

[0019] Step 2.4: After coating, remove the blade from the turntable and dismantle the coating device; use non-metallic tools to remove residues on the blade surface and clean the coating flash to make the coating edge transition smooth; use clean and dry compressed air treated with an oil-water separator to blow off coating debris and other excess materials on the blade, and wipe the blade clean with a soft cloth or impregnated cotton wool.

[0020] Furthermore, in the above-mentioned method for coating wear-resistant coating on dual-journal adjustable stator blades of an aircraft engine, after step 2.1, the sandblasting is completed, spraying is performed within 2 hours. If spraying is not performed within 30 minutes, the blade is covered with kraft paper.

[0021] Furthermore, in the above-mentioned method for coating a wear-resistant coating on an adjustable stator blade of a dual-journal type aircraft engine, during the spraying process in step 2.3, the blade is blown and cooled with compressed air filtered through an oil-water separator, and the cooling air duct is fixed on the spray gun. The cooling air parameters are: cooling air duct diameter 7.0~9.0mm, cooling air pressure 0.3~0.5MPa, cooling air distance 290~380mm, and cooling air angle 70°~90°.

[0022] Furthermore, in the above-mentioned method for coating wear-resistant coating on adjustable stator blades of dual-journal type of aircraft engines, before spraying in step 2.3, the spraying program is run 1-2 times according to the coating parameters without powder feeding, the blades are preheated, the maximum preheating temperature does not exceed 200°C, and the blade temperature is monitored with an infrared thermometer.

[0023] Furthermore, in the above-mentioned method for coating wear-resistant coating on dual-journal adjustable stator blades of an aircraft engine, step 3 of grinding is specifically to grind the wear-resistant coating on an external circular grinding machine with a spindle speed of 1500 rpm and a cutting speed of 0.05 mm.

[0024] Advantages and beneficial effects of the present invention:

[0025] 1. This invention solves the technical challenge of applying a wear-resistant coating to the journals and shoulders of dual-journal adjustable stator blades by combining a dedicated coating device with a supersonic flame spraying process. The dedicated coating device achieves precise protection of narrow areas, preventing erosion of non-coated areas by the high-temperature, high-velocity flame flow. The supersonic flame spraying process optimizes the parameters of the sandblasting, spraying, and cooling steps to ensure a dense coating with excellent wear resistance. Post-coating treatment further improves surface quality through grinding, achieving a coating surface roughness of Ra 0.4μm.

[0026] 2. The plating method proposed in this invention significantly improves the wear resistance and service life of the coating, providing a strong guarantee for the efficient production and reliable operation of aircraft engine parts;

[0027] 3. The proposed supersonic flame spray coating process offers low heat input, high coating density, and significantly improved production efficiency, meeting the demands of mass production of aircraft engine components. The specialized coating device achieves efficient coating of confined areas by precisely protecting different spray zones, ensuring a long coating life and high reliability under demanding service conditions. Furthermore, by optimizing process parameters, the present invention enhances the quality and performance of the coating, enabling it to adapt to the complex service environment of aircraft engines. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of the spraying area of ​​the stator blade;

[0029] Figure 2 This is a schematic diagram of the device for spraying the blade journal part;

[0030] Figure 3 This is the main view of the device in the tilted state when spraying the blade journal position;

[0031] Figure 4 for Figure 3 AA section view;

[0032] Figure 5 This is a schematic diagram of the device for spraying the blade shoulder;

[0033] Figure 6 This is the main view of the device in the tilted state when spraying the blade shoulder area;

[0034] Figure 7 for Figure 6 BB section view;

[0035] Figure 8 This is a metallographic image of the coating in the M area of ​​the sprayed journal neck in Example 1;

[0036] Figure 9This is a metallographic image of the coating in the N zone of the sprayed journal neck in Example 1;

[0037] Figure 10 This is a metallographic image of the coating sprayed on the shoulder of Example 1;

[0038] In the figure, 1-cylinder; 2-cylinder cover a; 3-long sleeve; 4-cylinder cover b; 5-short sleeve; 6-clip; 7-pin; 8-cap nut; 9-nut; 10-bolt; 11-shaft neck position M zone; 12-shaft neck position N zone; 13-shaft shoulder position. DETAILED DESCRIPTION

[0039] In a specific embodiment, Figure 1 As shown, the present invention sprays the spraying area of ​​the dual-journal adjustable stator blade of the aircraft engine, specifically comprising the following steps:

[0040] Step 1: Design a coating device and install a double-journal adjustable stator blade on a dedicated coating device to protect the non-coated area of ​​the blade. The coating area includes the blade journal area M 11, the journal area N 12, and the blade shoulder area 13.

[0041] like Figure 2-7 As shown, the plating device consists of a cylinder 1, a cylinder cover a2, a long sleeve 3, a cylinder cover b4, a short sleeve 5, a clip 6, a pin 7, a cap nut 8, a nut 9 and a bolt 10, wherein:

[0042] When plating the blade neck portion M zone 11 and the blade neck portion N zone 12, the blade is installed in the barrel 1 and positioned using the shoulder surface and inner hole of the barrel 1; the barrel cover b4 is screwed into the threaded end of the barrel 1 to protect the upper shoulder surface of the blade; at least two clips 6 are fixed to the shaft diameter of the blade using nuts 9 and bolts 10 to protect the non-spraying area in the middle of the shaft diameter; the short sleeve 5 is installed into the upper end of the blade; and the plating device is connected to the spraying equipment using a pin 7 and a cap nut 8.

[0043] When plating the blade shoulder portion 13, remove the cylinder cover b, the short sleeve 5 and the clip 6, and screw the cylinder cover a2 into the threaded end of the cylinder 1, and install the long sleeve 3 into the upper end of the blade;

[0044] Step 2: coating the coating area with a WC-Co wear-resistant coating by using a supersonic flame spraying process using a mixture of aviation kerosene and oxygen;

[0045] Step 2.1, dry sandblasting treatment is performed on the plated area, using a sandblasting gun with a nozzle diameter of 7.0-8.5 mm, 60# white corundum sand, a sandblasting distance of 140-180 mm, and a compressed air pressure of 0.25-0.35 MPa. The sandblasting angle for the blade neck is 55°-85°, and the sandblasting angle for the blade shoulder is 15°-45°. The turntable speed is 30-40 rpm, and the sandblasting gun movement speed is 5 mm / s. After the sandblasting is completed, spraying is performed within 2 hours. If spraying is not performed within 30 minutes, the blade is covered with kraft paper.

[0046] Step 2.2, fixing the sandblasted blades and the coating device on a ten-station turntable to achieve simultaneous spraying of 10 blades;

[0047] Step 2.3, using a kerosene-oxygen mixed fuel supersonic flame spraying process to coat a WC-Co wear-resistant coating, the coating parameters include: barrel length 101.6 mm, spraying distance 350-380 mm, powder feed rate 80-90 g / min, oxygen flow rate 800-880 NLPM, kerosene flow rate 18-22 L / h, argon carrier gas, carrier gas flow rate 9.0-10.0 NLPM, part rotation speed 540-660 rpm, spray gun movement speed 90-110 mm / s; wherein, the spraying angle for the blade journal portion is 80°-90°, and the spraying angle for the blade shoulder portion is 65-75°; the coating thickness is 0.2-0.3 mm; and the hardness value is ≥950 HV0.3;

[0048] Before spraying, run the spraying program 1-2 times according to the coating parameters without feeding powder, preheat the blades, the maximum preheating temperature does not exceed 200℃, and monitor the blade temperature with an infrared thermometer;

[0049] During the spraying process, the blades are cooled with compressed air filtered through an oil-water separator. The cooling air duct is fixed on the spray gun. The cooling air parameters are: cooling air duct diameter 7.0~9.0mm, cooling air pressure 0.3~0.5MPa, cooling air distance 290~380mm, cooling air angle 70°~90°;

[0050] Step 2.4: After coating, remove the blade from the turntable and dismantle the coating device; use non-metallic tools to remove residues on the blade surface and clean the coating flash to make the coating edge transition smooth; use clean and dry compressed air treated with an oil-water separator to blow away coating debris and other excess materials on the blade, and wipe the blade clean with a soft cloth or impregnated absorbent cotton;

[0051] Step 3: Grind the wear-resistant coating on the sprayed coating surface using an external circular grinding machine with a spindle speed of 1500 rpm and a cutting speed of 0.05 mm, so that the coating surface has a uniform metallic luster and a roughness Ra < 0.6 μm;

[0052] The components of the WC-Co wear-resistant coating powder include, by weight percentage, Co: 15.0-18.0wt%, C: 4.5-5.6wt%, Fe not more than 2.0wt%, W not less than 76.0wt%, and the total amount of other impurities not more than 1.0wt%. The powder particle size distribution range must meet the following requirements: particle size of 53μm and above is not more than 2.0wt%, particle size of 45μm-53μm is not more than 20.0wt%, particle size of 10μm-45μm is not less than 75.0wt%, and particle size of 10μm and below is not more than 3.0wt%.

[0053] The specific implementation methods of the present invention are described in further detail below with reference to the examples.

[0054] Example 1

[0055] This embodiment provides a method for coating a wear-resistant coating on a dual-journal adjustable stator blade of an aircraft engine, comprising the following steps:

[0056] Step 1: Install a double-journal adjustable stator blade on a dedicated plating device to protect the non-plated area of ​​the blade. The plating area includes the blade journal area M 11, the journal area N 12, and the blade shoulder area 13.

[0057] When plating the blade neck portion M zone 11 and the blade neck portion N zone 12, the blade is installed in the barrel 1 and positioned using the shoulder surface and inner hole of the barrel 1; the barrel cover b4 is screwed into the threaded end of the barrel 1 to protect the upper shoulder surface of the blade; at least two clips 6 are fixed to the shaft diameter of the blade using nuts 9 and bolts 10 to protect the non-spraying area in the middle of the shaft diameter; the short sleeve 5 is installed into the upper end of the blade; and the plating device is connected to the spraying equipment using a pin 7 and a cap nut 8.

[0058] When plating the blade shoulder portion 13, remove the cylinder cover b, the short sleeve 5 and the clip 6, and screw the cylinder cover a2 into the threaded end of the cylinder 1, and install the long sleeve 3 into the upper end of the blade;

[0059] Step 2: coating the coating area with a WC-Co wear-resistant coating by using a supersonic flame spraying process using a mixture of aviation kerosene and oxygen;

[0060] Step 2.1, dry sandblasting the plated area, using a sandblasting gun with a nozzle diameter of 7.0 mm, 60# white corundum sand, a sandblasting distance of 140 mm, and a compressed air pressure of 0.25 MPa; wherein the sandblasting angle for the blade neck area M 11 and the neck area N 12 is 55°, and the sandblasting angle for the blade shoulder area 13 is 15°; the turntable speed is 30 rpm, and the sandblasting gun movement speed is 5 mm / s; after the sandblasting is completed, spraying is performed within 2 hours. If spraying is not performed within 30 minutes, the blade is covered with kraft paper;

[0061] Step 2.2, fixing the sandblasted blades and the coating device on a ten-station turntable to achieve simultaneous spraying of 10 blades;

[0062] Step 2.3, using a kerosene-oxygen mixed fuel supersonic flame spraying process to coat a WC-Co wear-resistant coating, the coating parameters include: barrel length 101.6 mm, spraying distance 350 mm, powder feed rate 80 g / min, oxygen flow rate 800 NLPM, kerosene flow rate 18 L / h, carrier gas argon, carrier gas flow rate 9.0 NLPM, part rotation speed 540-660 rpm, and spray gun movement speed 90 mm / s; wherein, the spraying angle for the blade shaft neck position M area 11 and the shaft neck position N area 12 is 80°, and the spraying angle for the blade shaft shoulder area 13 is 65°; the coating thickness is 0.2 mm, the coating hardness of the shaft neck position M area 11 is 1267 HV0.3, the coating hardness of the shaft neck position N area 12 is 1289 HV0.3, and the coating hardness of the shaft shoulder area 13 is 1140.9 HV0.3;

[0063] Before spraying, run the spraying program once according to the coating parameters without powder feeding, preheat the blade to a maximum temperature of 200°C, and monitor the blade temperature with an infrared thermometer;

[0064] During the spraying process, the blades are cooled by blowing compressed air filtered through an oil-water separator. The cooling air duct is fixed on the spray gun. The cooling air parameters are: cooling air duct diameter 7.0 mm, cooling air pressure 0.3 MPa, cooling air distance 290 mm, cooling air angle 70°.

[0065] Step 2.4: After coating, remove the blade from the turntable and dismantle the coating device; use non-metallic tools to remove residues on the blade surface and clean the coating flash to make the coating edge transition smooth; use clean and dry compressed air treated with an oil-water separator to blow away coating debris and other excess materials on the blade, and wipe the blade clean with a soft cloth or impregnated absorbent cotton;

[0066] Step 3: Grind the wear-resistant coating on the sprayed coating surface using an external circular grinding machine with a spindle speed of 1500 rpm and a cutting speed of 0.05 mm, so that the coating surface has a uniform metallic luster and a roughness Ra of 0.5 μm;

[0067] The WC-Co wear-resistant coating powder comprises, by weight percentage, Co: 15.0 wt%, C: 4.5 wt%, Fe: 2 wt%, W: 78.0 wt%, and the total amount of other impurities: 0.5 wt%. The powder particle size distribution range must meet the following requirements: 2.0 wt% for particles above 53 μm, 20.0 wt% for particles between 45 μm and 53 μm, 75.0 wt% for particles between 10 μm and 45 μm, and 3.0 wt% for particles below 10 μm.

[0068] like Figure 8-10 As shown in FIG, the metallographic images of the spray coating in the M zone, N zone and shoulder of the shaft neck in this embodiment show that the coating has good interface bonding with the substrate, the coating structure is uniform and complete, there is no delamination, interface separation and transverse cracks, there are no unmelted particles, and the porosity is below 1%.

[0069] Example 2

[0070] This embodiment provides a method for coating a wear-resistant coating on a dual-journal adjustable stator blade of an aircraft engine, comprising the following steps:

[0071] Step 1: Install a double-journal adjustable stator blade on a dedicated plating device to protect the non-plated area of ​​the blade. The plating area includes the blade journal area M 11, the journal area N 12, and the blade shoulder area 13.

[0072] When plating the blade neck portion M zone 11 and the blade neck portion N zone 12, the blade is installed in the barrel 1 and positioned using the shoulder surface and inner hole of the barrel 1; the barrel cover b4 is screwed into the threaded end of the barrel 1 to protect the upper shoulder surface of the blade; at least two clips 6 are fixed to the shaft diameter of the blade using nuts 9 and bolts 10 to protect the non-spraying area in the middle of the shaft diameter; the short sleeve 5 is installed into the upper end of the blade; and the plating device is connected to the spraying equipment using a pin 7 and a cap nut 8.

[0073] When plating the blade shoulder portion 13, remove the cylinder cover b, the short sleeve 5 and the clip 6, and screw the cylinder cover a2 into the threaded end of the cylinder 1, and install the long sleeve 3 into the upper end of the blade;

[0074] Step 2: coating the coating area with a WC-Co wear-resistant coating by using a supersonic flame spraying process using a mixture of aviation kerosene and oxygen;

[0075] Step 2.1. Dry sandblasting the plated area using a sandblasting gun with an 8.5 mm nozzle diameter, 60# white corundum sand, a sandblasting distance of 180 mm, and a compressed air pressure of 0.35 MPa. The sandblasting angle for the blade neck area M 11 and the neck area N 12 was 85°, and the sandblasting angle for the blade shoulder area 13 was 45°. The turntable speed was 40 rpm, and the sandblasting gun movement speed was 5 mm / s. After the sandblasting was completed, spraying was performed within 2 hours. If spraying was not performed within 30 minutes, the blade was covered with kraft paper.

[0076] Step 2.2, fixing the sandblasted blades and the coating device on a ten-station turntable to achieve simultaneous spraying of 10 blades;

[0077] Step 2.3, using a kerosene-oxygen mixed fuel supersonic flame spraying process to coat a WC-Co wear-resistant coating, the coating parameters include: barrel length 101.6 mm, spraying distance 380 mm, powder feed rate 90 g / min, oxygen flow rate 880 NLPM, kerosene flow rate 22 L / h, argon carrier gas, carrier gas flow rate 10.0 NLPM, part rotation speed 660 rpm, and spray gun movement speed 110 mm / s; wherein, the spraying angle for the blade shaft neck position M area 11 and the shaft neck position N area 12 is 90°, and the spraying angle for the blade shaft shoulder area 13 is 75°; the coating thickness is 0.3 mm; the coating hardness of the shaft neck position M area 11 is 1258 HV0.3, the coating hardness of the shaft neck position N area 12 is 1206 HV0.3, and the coating hardness of the shaft shoulder area 13 is 1162 HV0.3;

[0078] Before spraying, run the spraying program twice according to the coating parameters without powder feeding, preheat the blades to a maximum temperature not exceeding 200°C, and monitor the blade temperature with an infrared thermometer;

[0079] During the spraying process, the blades are cooled with compressed air filtered through an oil-water separator. The cooling air duct is fixed on the spray gun. The cooling air parameters are: cooling air duct diameter 9.0 mm, cooling air pressure 0.5 MPa, cooling air distance 380 mm, cooling air angle 90°.

[0080] Step 2.4: After coating, remove the blade from the turntable and dismantle the coating device; use non-metallic tools to remove residues on the blade surface and clean the coating flash to make the coating edge transition smooth; use clean and dry compressed air treated with an oil-water separator to blow away coating debris and other excess materials on the blade, and wipe the blade clean with a soft cloth or impregnated absorbent cotton;

[0081] Step 3: Grind the wear-resistant coating on the sprayed coating surface using an external circular grinding machine with a spindle speed of 1500 rpm and a cutting speed of 0.05 mm, so that the coating surface has a uniform metallic luster and a roughness of 0.5 μm;

[0082] The WC-Co wear-resistant coating powder comprises, by weight percentage, Co: 18.0wt%, C: 5.6wt%, Fe: 0.3wt%, W: 76.0wt%, and the total amount of other impurities: 0.1wt%. The powder particle size distribution range must meet the following requirements: 1.0wt% for particles above 53μm, 15.0wt% for particles between 45μm and 53μm, 82.0wt% for particles between 10μm and 45μm, and 2.0wt% for particles below 10μm.

[0083] Example 3

[0084] This embodiment provides a method for coating a wear-resistant coating on a dual-journal adjustable stator blade of an aircraft engine, comprising the following steps:

[0085] Step 1: Design a coating device and install a double-journal adjustable stator blade on a dedicated coating device to protect the non-coated area of ​​the blade. The coating area includes the blade journal area M 11, the journal area N 12, and the blade shoulder area 13.

[0086] When plating the blade neck portion M zone 11 and the blade neck portion N zone 12, the blade is installed in the barrel 1 and positioned using the shoulder surface and inner hole of the barrel 1; the barrel cover b4 is screwed into the threaded end of the barrel 1 to protect the upper shoulder surface of the blade; at least two clips 6 are fixed to the shaft diameter of the blade using nuts 9 and bolts 10 to protect the non-spraying area in the middle of the shaft diameter; the short sleeve 5 is installed into the upper end of the blade; and the plating device is connected to the spraying equipment using a pin 7 and a cap nut 8.

[0087] When plating the blade shoulder portion 13, remove the cylinder cover b, the short sleeve 5 and the clip 6, and screw the cylinder cover a2 into the threaded end of the cylinder 1, and install the long sleeve 3 into the upper end of the blade;

[0088] Step 2: coating the coating area with a WC-Co wear-resistant coating by using a supersonic flame spraying process using a mixture of aviation kerosene and oxygen;

[0089] Step 2.1. Dry sandblasting the plated area using a sandblasting gun with an 8.0 mm nozzle diameter, 60# white corundum sand, a blasting distance of 50 mm, and a compressed air pressure of 0.3 MPa. The sandblasting angle for the blade neck area M 11 and the neck area N 12 was 60°, and the sandblasting angle for the blade shoulder area 13 was 30°. The turntable speed was 35 rpm, and the sandblasting gun movement speed was 5 mm / s. After the sandblasting was completed, spraying was performed within 2 hours. If spraying was not performed within 30 minutes, the blade was covered with kraft paper.

[0090] Step 2.2, fixing the sandblasted blades and the coating device on a ten-station turntable to achieve simultaneous spraying of 10 blades;

[0091] Step 2.3, using a kerosene-oxygen mixed fuel supersonic flame spraying process to coat a WC-Co wear-resistant coating, the coating parameters include: barrel length 101.6 mm, spraying distance 360 ​​mm, powder feed rate 85 g / min, oxygen flow rate 850 NLPM, kerosene flow rate 19 L / h, carrier gas argon, carrier gas flow rate 9.5 NLPM, part rotation speed 500 rpm, and spray gun movement speed 100 mm / s; wherein, the spraying angle for the blade shaft neck position M area 11 and the shaft neck position N area 12 is 85°, and the spraying angle for the blade shaft shoulder area 13 is 65-75°; the coating thickness is 0.241 mm; the coating hardness of the shaft neck position M area 11 is 1210 HV0.3, the coating hardness of the shaft neck position N area 12 is 1013 HV0.3, and the coating hardness of the shaft shoulder area 13 is 1238 HV0.3;

[0092] Before spraying, run the spraying program twice according to the coating parameters without powder feeding, preheat the blade to a maximum temperature of 180°C, and monitor the blade temperature with an infrared thermometer;

[0093] During the spraying process, the blades are cooled by blowing compressed air filtered through an oil-water separator. The cooling air duct is fixed on the spray gun. The cooling air parameters are: cooling air duct diameter 8.0 mm, cooling air pressure 0.4 MPa, cooling air distance 320 mm, cooling air angle 80°.

[0094] Step 2.4: After coating, remove the blade from the turntable and dismantle the coating device; use non-metallic tools to remove residues on the blade surface and clean the coating flash to make the coating edge transition smooth; use clean and dry compressed air treated with an oil-water separator to blow away coating debris and other excess materials on the blade, and wipe the blade clean with a soft cloth or impregnated absorbent cotton;

[0095] Step 3: Grind the wear-resistant coating on the sprayed coating surface using an external circular grinding machine with a spindle speed of 1500 rpm and a cutting speed of 0.05 mm, so that the coating surface has a uniform metallic luster and a roughness Ra of 0.5 μm;

[0096] The WC-Co wear-resistant coating powder comprises, by weight percentage, Co: 16.0wt%, C: 5.0wt%, Fe2.0wt%, W76.5wt%, and 0.5wt% of other impurities. The powder particle size distribution range must meet the following requirements: 1.0wt% for particles above 53μm, 16.0wt% for particles between 45μm and 53μm, 81.0wt% for particles between 10μm and 45μm, and 2.0wt% for particles below 10μm.

[0097] In practical applications, the present invention has been successfully applied to the production of dual-neck adjustable stator blades for aircraft engines. Through verification in batch production, the parts qualification rate reached 100%, realizing the engineering application of supersonic flame spraying technology in small-sized spray parts. This achievement not only provides a reference for the subsequent spraying production of similar parts, but also greatly improves the manufacturing level and technical competitiveness of aircraft engine parts. For example, in a certain batch of production, a total of 200 dual-neck adjustable stator blades were plated, and all parts met the requirements. Key indicators such as coating thickness and surface roughness met or exceeded the expected standards. At the same time, due to the optimization of spraying parameters and cooling measures, the production cycle was shortened by about 30%, which significantly improved production efficiency and economic benefits.

Claims

1. A method for coating a wear-resistant coating on an aircraft engine dual-journal adjustable stator blade, characterized in that: The following steps are involved: Step 1: Design a coating device and install the double-journal adjustable stator blade on a dedicated coating device to protect the non-coated area of ​​the blade. The coating area includes the blade journal and blade shoulder areas. The plating device is composed of a cylinder, a cylinder cover a, a long sleeve, a cylinder cover b, a short sleeve, a clip, a pin, a cap nut, a nut and a bolt, wherein: When plating the shaft neck of a blade, the blade is installed in a barrel and positioned using the shoulder surface and inner hole of the barrel; the barrel cover b is screwed into the threaded end of the barrel to protect the upper shoulder surface of the blade; at least two clips are fixed to the shaft diameter of the blade using nuts and bolts to protect the non-spraying area in the middle of the shaft diameter; a short sleeve is installed on the upper end of the blade; and the plating device is connected to the spraying equipment using a pin and a cap nut. When plating the blade shoulder, remove the barrel cover b, short sleeve and clip, screw the barrel cover a into the threaded end of the barrel, and install the long sleeve into the upper end of the blade; Step 2: coating the coating area with a WC-Co wear-resistant coating using a kerosene-oxygen mixed fuel supersonic flame spraying process; the coating thickness is 0.2-0.3 mm; Step 2.1, dry sandblasting treatment is performed on the plated area, wherein the sandblasting is performed using a sandblasting gun with a nozzle diameter of 7.0-8.5 mm, 60# white corundum sand, a sandblasting distance of 140-180 mm, and a compressed air pressure of 0.25-0.35 MPa; wherein the sandblasting angle for the blade shaft neck is 55°-85°, and the sandblasting angle for the blade shaft shoulder is 15°-45°; the turntable speed is 30-40 rpm, and the sandblasting gun movement speed is 5 mm / s; Step 2.2, fixing the sandblasted blades and the coating device on a ten-station turntable to achieve simultaneous spraying of 10 blades; Step 2.3, using a kerosene-oxygen mixed fuel supersonic flame spraying process to coat a WC-Co wear-resistant coating, the coating parameters include: barrel length 101.6 mm, spraying distance 350-380 mm, powder feed rate 80-90 g / min, oxygen flow rate 800-880 NLPM, kerosene flow rate 18-22 L / h, argon carrier gas, carrier gas flow rate 9.0-10.0 NLPM, part rotation speed 540-660 rpm, and spray gun movement speed 90-110 mm / s; wherein, the spray angle for the blade journal portion is 80°-90°, and the spray angle for the blade shoulder portion is 65-75°; Step 2.4: After coating, remove the blade from the turntable and dismantle the coating device; use non-metallic tools to remove residues on the blade surface and clean the coating flash to make the coating edge transition smooth; use clean and dry compressed air treated with an oil-water separator to blow away coating debris and other excess materials on the blade, and wipe the blade clean with a soft cloth or impregnated absorbent cotton; Step 3: Grind the surface of the sprayed coating to make the coating surface have a uniform metallic luster and a roughness Ra < 0.6 μm; The components of the WC-Co wear-resistant coating powder include, by weight percentage, Co: 15.0-18.0wt%, C: 4.5-5.6wt%, Fe not more than 2.0wt%, W not less than 76.0wt%, and the total amount of other impurities not more than 1.0wt%. The powder particle size distribution range must meet the following requirements: particle size of 53μm and above is not more than 2.0wt%, particle size of 45μm-53μm is not more than 20.0wt%, particle size of 10μm-45μm is not less than 75.0wt%, and particle size of 10μm and below is not more than 3.0wt%.

2. The method for coating a wear-resistant coating on an aircraft engine dual-journal adjustable stator blade according to claim 1, characterized in that: After step 2.1, the blades were sprayed within 2 hours. If spraying was not performed within 30 minutes, the blades were covered with kraft paper.

3. The method for coating a wear-resistant coating on an aircraft engine dual-journal adjustable stator blade according to claim 1, characterized in that: During the spraying process of step 2.3, the blades are cooled by blowing compressed air filtered through an oil-water separator. The cooling air duct is fixed on the spray gun. The cooling air parameters are: cooling air duct diameter 7.0~9.0mm, cooling air pressure 0.3~0.5MPa, cooling air distance 290~380mm, and cooling air angle 70°~90°.

4. The method for coating a wear-resistant coating on an aircraft engine dual-journal adjustable stator blade according to claim 1, characterized in that: Step 2.3 Before spraying, run the spraying program 1-2 times according to the coating parameters without powder feeding, preheat the blade, the maximum preheating temperature does not exceed 200℃, and monitor the blade temperature with an infrared thermometer.

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