A method for reducing interface contamination of curved surfaces of Mo coatings used for aviation sealing

Abstract

The invention discloses a method for reducing interface pollution of a curved surface of a Mo coating for aviation sealing. The method comprises the following steps: 1) bending a stainless steel sample into a sample with a diameter of R47-49 mm, cleaning the sample with alcohol or gasoline, and then fixing the sample on a tooling, wherein the tooling fixture rotates on a turntable at a speed of 80-100 r / min; 2) performing surface activation and coarsening treatment on the curved sample with 240 mesh zirconium corundum; controlling the angle between the sand discharged from a sandblasting gun and the contact surface of the curved surface sample at 20°-40°; the spray gun pressure is 0.15-0.25 Mpa; and the sand blowing distance is 50-80 mm; 3) spraying a Mo coating on the curved sample obtained in step 2) by adopting an APS atmospheric plasma spraying technology. The invention can significantly reduce the interface pollution of the curved surface of the Mo coating for sealing of aircraft engine parts.

Description

Technical field:

[0001] The invention relates to a method for reducing interface contamination of a curved surface of a Mo coating used for aviation sealing. Background technology:

[0002] In the aviation field, iron-based alloys have good strength, plasticity, and toughness, and are often used in the preparation of various parts. However, during service, there are some harsh friction and wear environments; iron-based alloys will encounter severe wear and consumption, resulting in parts failure. In order to improve the wear resistance of the workpiece, a layer of wear-resistant and sealed coating is prepared on the surface of the workpiece to improve the wear resistance of the workpiece and extend its service life. APS plasma spraying technology has the characteristics of high deposition rate, high coating density, low cost, and convenient processing; so APS plasma spraying technology is selected. Japanese experts and scholars have found that Mo will oxidize during the friction and wear process of parts; it can form MoO3 with a low friction coefficient; it plays a role of self-lubrication and wear reduction in friction and wear; thereby improving the wear resistance of parts.

[0003] APS atmospheric plasma spraying Mo coating is a relatively advantageous technology for sealing coatings in the aviation field. The most critical issue for engineering applications is the coating interface bonding state. The coating is directly sprayed on the coating bonding interface; the bonding force is often relatively low. Sandblasting is generally used to improve the coating interface bonding state. The commonly used sandblasting method is to form a vertical 90° to the sample surface; however, the sample surface in the conventional vertical 90° to the sample surface is flat; the curved surface uses a vertical 90° sandblasting method to form a vertical 90° to the sample surface, which will produce too much interface contamination at the coating interface; the direct result is too much interface contamination, which will lead to a decrease in the bonding force between the coating and the substrate, plus the friction, wear and stress generated by the coating during later use; it is more likely to cause coating failure, peeling and other phenomena. When the working environment is severe, it will cause the fracture and failure of parts. This will lead to equipment damage and equipment downtime. Summary of the invention:

[0004] The purpose of the present invention is to provide a method for reducing interface contamination of curved surfaces of Mo coatings used for aviation sealing, thereby solving the problem of excessive interface contamination of MO coatings used for sealing of aircraft engine parts.

[0005] The present invention is achieved through the following technical solutions:

[0006] A method for reducing interface contamination of a curved surface of a Mo coating for aviation sealing, the method comprising the following steps:

[0007] 1) Bend the stainless steel sample into a R47-49mm sample and clean it with alcohol or gasoline, then fix it on the fixture, and the fixture rotates on the turntable at a speed of 80-100r / min;

[0008] 2) Use 240 mesh zirconium corundum to perform surface activation and roughening treatment on the curved sample; the angle between the sand discharged from the sandblasting gun and the contact surface of the curved surface sample is controlled at 20°-40°; the spray gun pressure is 0.15-0.25Mpa; the sand blasting distance is 50-80mm;

[0009] Alternatively, the bending specimen may be subjected to surface activation and roughening treatment by using an argon ion polishing method or surface activation and roughening treatment by using an electrolytic polishing method;

[0010] 3) APS atmospheric plasma spraying technology is used to spray Mo coating on the bending sample obtained in step 2), and the conditions are: hydrogen: 10-12L / h; argon: 40-45L / h; current: 430-450A; voltage: 90-120V; spray distance: 80-100mm; powder feeding amount: 30-40g / min.

[0011] Preferably, in step 1), the turntable rotates at a speed of 90 r / min.

[0012] Preferably, in step 2), the nozzle diameter is Φ10 mm; the angle between the sand discharged from the sandblasting gun nozzle and the contact surface of the curved surface sample is 30°, the spray gun pressure is 0.2 Mpa, and the sand blasting distance is 60 mm.

[0013] Among them, the argon ion polishing process parameters are: voltage: 3-5Kev, time: 1h, vacuum degree: 3E -5 Pa.

[0014] Among them, the electrolytic polishing process parameters are: voltage: 25V, time: 60s, current: 0.4-0.6mA, temperature: -10℃.

[0015] In particular, on rainy days and when the weather is humid, heat treatment is performed on the bending sample before step 3), the heat treatment temperature is 1050-1100° C., and the insulation time is 3 hours.

[0016] The beneficial effects of the present invention are as follows: the present invention can significantly reduce the interface contamination of the curved surface of the Mo coating used for sealing aircraft engine parts. Description of the drawings:

[0017] Figure 1 This is a metallographic diagram of the aviation seal Mo coating before the implementation of the patented technology in Example 1;

[0018] Figure 2 This is a metallographic diagram of the aviation sealing Mo coating after the patent technology is implemented in Example 1;

[0019] Figure 3 is the FSD-EBSD image of the surface after substrate-argon ion polishing in Example 3;

[0020] Figure 4 is a SEM image of the surface of the substrate after electrolytic polishing in Example 4;

[0021] Figure 5 is a metallographic image of the substrate in Example 3 - without argon ion polishing - spray coating;

[0022] Figure 6 is a metallographic image of the substrate-after argon ion polishing-sprayed coating in Example 3;

[0023] Figure 7 is a metallographic image of the substrate in Example 4 - without electrolytic polishing - spray coating;

[0024] Figure 8 is a metallographic image of the substrate-after electrolytic polishing-spray coating in Example 4;

[0025] Fig. 9 This is the metallographic image of the spray coating of Example 9 without heat treatment;

[0026] Fig.10 This is the metallographic image of the spray coating after heat treatment in Example 9. Specific implementation method:

[0027] The following is a further description of the present invention, rather than a limitation of the present invention.

[0028] Embodiment 1:

[0029] Using 316L stainless steel as the base, bend the 100×14×2mm (length, width and height) sample stainless steel into a sample with R48mm and thickness of 2mm. Then clean it with alcohol or gasoline; fix the cleaned bent sample on a fixture with R60mm, height: 30mm, wall thickness: 12mm, and the fixture rotates on the turntable at a speed of 80r / min.

[0030] The surface of the curved sample was activated and roughened with 240 mesh zirconium corundum. The angle between the sand discharged from the sandblasting gun and the surface of the curved sample was controlled at 30°. The spray gun pressure was 0.2Mpa; the sandblasting distance was 50mm.

[0031] Then, the Mo coating was sprayed on the bending specimen by APS atmospheric plasma spraying technology; the test conditions were: hydrogen: 10 L / h; argon: 40 L / h; current: 430 A; voltage: 100 V; spray distance: 90 mm; powder feeding amount: 35 g / min.

[0032] See the schematic diagram of interface contamination of aviation seal Mo coating before and after the implementation of this patent technology. Figure 1 and Figure 2It can be seen that the present invention can significantly reduce the interface contamination of the curved surface of the Mo coating used for sealing aircraft engine parts.

[0033] Embodiment 2:

[0034] Using 314 stainless steel as the base, bend the 100×14×2mm (length, width and height) sample stainless steel into a sample with R48mm and thickness of 2mm. Then clean it with alcohol or gasoline; fix the cleaned bent sample on a fixture with R60mm, height: 30mm, wall thickness: 12mm, and the fixture rotates on the turntable at a speed of 80r / min.

[0035] The surface of the curved specimen was activated and roughened with 240 mesh zirconium corundum. The angle between the sand discharged from the sandblasting gun and the surface of the curved specimen was controlled at 30°. The spray gun pressure was 0.2Mpa; the sandblasting distance was 80mm.

[0036] Then, the Mo coating was sprayed on the bending specimen by APS atmospheric plasma spraying technology; the test conditions were: hydrogen: 10 L / h; argon: 40 L / h; current: 430 A; voltage: 100 V; spray distance: 90 mm; powder feeding amount: 35 g / min.

[0037] Example 3

[0038] With 304 stainless steel as the base, bend the 100×14×2mm (length, width and height) sample stainless steel into a sample with R48mm and thickness of 2mm. Then clean it with alcohol or gasoline; fix the cleaned bent sample on a fixture with R60mm, height: 30mm, wall thickness: 12mm, and the fixture rotates on the turntable at a speed of 80r / min.

[0039] The surface of the cleaned bending sample was activated and roughened by argon ion polishing. The argon ion polishing process parameters were: voltage: 3-5Kev, time: 1h, vacuum degree: 3E -5 Pa.

[0040] The FSD-EBSD map of the substrate-argon ion polished surface is shown in Figure 3 .

[0041] Then, the Mo coating was sprayed on the bending specimen by APS atmospheric plasma spraying technology; the test conditions were: hydrogen: 10 L / h; argon: 40 L / h; current: 430 A; voltage: 100 V; spray distance: 90 mm; powder feeding amount: 35 g / min.

[0042] See the schematic diagram of interface contamination of aviation seal Mo coating before and after the implementation of the method of this embodiment. Figure 5 and Figure 6It can be seen that this embodiment can significantly reduce the interface contamination of the curved surface of the Mo coating used for sealing aircraft engine parts.

[0043] Example 4

[0044] Using 316L stainless steel as the base, bend the 100×14×2mm (length, width and height) sample stainless steel into a sample with R48mm and thickness of 2mm. Then clean it with alcohol or gasoline; fix the cleaned bent sample on a fixture with R60mm, height: 30mm, wall thickness: 12mm, and the fixture rotates on the turntable at a speed of 80r / min.

[0045] The cleaned bending specimens were subjected to surface activation and roughening treatment by electrolytic polishing. The electrolytic polishing process parameters are: voltage: 25V, time: 60s, current: 0.4-0.6mA, temperature: -10°C. The SEM image of the substrate-surface after electrolytic polishing is shown in Figure 4 .

[0046] Then, the Mo coating was sprayed on the bending specimen by APS atmospheric plasma spraying technology; the test conditions were: hydrogen: 10 L / h; argon: 40 L / h; current: 430 A; voltage: 100 V; spray distance: 90 mm; powder feeding amount: 35 g / min.

[0047] See the schematic diagram of interface contamination of aviation seal Mo coating before and after the implementation of the technology of this embodiment. Figure 7 and Figure 8 It can be seen that the present invention can significantly reduce the interface contamination of the curved surface of the Mo coating used for sealing aircraft engine parts.

[0048] Embodiment 5:

[0049] Using 316L stainless steel as the base, bend the 100×14×2mm (length, width and height) sample stainless steel into a sample with R48mm and thickness of 2mm. Then clean it with alcohol or gasoline; fix the cleaned bent sample on a fixture with R60mm, height: 30mm, wall thickness: 12mm, and the fixture rotates on the turntable at a speed of 80r / min.

[0050] The surface of the curved sample was activated and roughened with 240 mesh zirconium corundum. The angle between the sand discharged from the sandblasting gun and the surface of the curved sample was controlled at 20°. The spray gun pressure was 0.2Mpa; the sandblasting distance was 50mm.

[0051] Then, the Mo coating was sprayed on the bending specimen by APS atmospheric plasma spraying technology; the test conditions were: hydrogen: 10 L / h; argon: 40 L / h; current: 430 A; voltage: 100 V; spray distance: 90 mm; powder feeding amount: 35 g / min.

[0052] Embodiment 6:

[0053] Using 316L stainless steel as the base, bend the 100×14×2mm (length, width and height) sample stainless steel into a sample with R48mm and thickness of 2mm. Then clean it with alcohol or gasoline; fix the cleaned bent sample on a fixture with R60mm, height: 30mm, wall thickness: 12mm, and the fixture rotates on the turntable at a speed of 80r / min.

[0054] The surface of the curved specimen was activated and roughened with 240 mesh zirconium corundum. The angle between the sand discharged from the sandblasting gun and the surface of the curved specimen was controlled at 40°. The spray gun pressure was 0.2Mpa; the sandblasting distance was 50mm.

[0055] Then, the Mo coating was sprayed on the bending specimen by APS atmospheric plasma spraying technology; the test conditions were: hydrogen: 10 L / h; argon: 40 L / h; current: 430 A; voltage: 100 V; spray distance: 90 mm; powder feeding amount: 35 g / min.

[0056] Embodiment 7:

[0057] Using 316L stainless steel as the base, bend the 100×14×2mm (length, width and height) sample stainless steel into a sample with R48mm and thickness of 2mm. Then clean it with alcohol or gasoline; fix the cleaned bent sample on a fixture with R60mm, height: 30mm, wall thickness: 12mm, and the fixture rotates on the turntable at a speed of 80r / min.

[0058] The surface of the curved specimen was activated and roughened with 240 mesh zirconium corundum. The angle between the sand discharged from the sandblasting gun and the surface of the curved specimen was controlled at 30°. The spray gun pressure was 0.15Mpa; the sandblasting distance was 50mm.

[0059] Then, the Mo coating was sprayed on the bending specimen by APS atmospheric plasma spraying technology; the test conditions were: hydrogen: 10 L / h; argon: 40 L / h; current: 430 A; voltage: 100 V; spray distance: 90 mm; powder feeding amount: 35 g / min.

[0060] Embodiment 8:

[0061] Using 316L stainless steel as the base, bend the 100×14×2mm (length, width and height) sample stainless steel into a sample with R48mm and thickness of 2mm. Then clean it with alcohol or gasoline; fix the cleaned bent sample on a fixture with R60mm, height: 30mm, wall thickness: 12mm, and the fixture rotates on the turntable at a speed of 80r / min.

[0062] The surface of the curved specimen was activated and roughened with 240 mesh zirconium corundum. The angle between the sand discharged from the sandblasting gun and the surface of the curved specimen was controlled at 30°. The spray gun pressure was 0.25Mpa; the sand blasting distance was 50mm.

[0063] Then, the Mo coating was sprayed on the bending specimen by APS atmospheric plasma spraying technology; the test conditions were: hydrogen: 10 L / h; argon: 40 L / h; current: 430 A; voltage: 100 V; spray distance: 90 mm; powder feeding amount: 35 g / min.

[0064] Example 9

[0065] The difference from Example 1 is that the bending sample is subjected to heat treatment before the Mo coating is sprayed on the bending sample by APS atmospheric plasma spraying technology. The other aspects are the same as Example 1.

[0066] With stainless steel as the base, bend the 100×14×2mm (length, width and height) sample stainless steel into a sample with R48mm and thickness of 2mm. Then clean it with alcohol or gasoline; fix the cleaned bent sample on a fixture with R60mm, height: 30mm, wall thickness: 12mm, and the fixture rotates on the turntable at a speed of 80r / min.

[0067] The surface of the curved sample was activated and roughened with 240 mesh zirconium corundum. The angle between the sand discharged from the sandblasting gun and the surface of the curved sample was controlled at 30°. The spray gun pressure was 0.2Mpa; the sandblasting distance was 50mm.

[0068] Then, the bending specimen was heat treated at a temperature of 1050-1100°C and a holding time of 3 hours. Then, the Mo coating was sprayed by APS atmospheric plasma spraying technology; the test conditions were: hydrogen: 10L / h; argon: 40L / h; current: 430A; voltage: 100V; spray distance: 90mm; powder feeding amount: 35g / min.

[0069] See the schematic diagram of interface contamination of aviation seal Mo coating before and after the implementation of the technology of this embodiment. Fig. 9 and Fig.10 It can be seen that the present invention can significantly reduce the interface contamination of the curved surface of the Mo coating used for sealing aircraft engine parts. For samples that have been heat treated on rainy days and in humid weather, the effect will be better.

[0070] Comparative Example 1

[0071] The difference between this comparative example and Example 1 is that the angle between the sand discharged from the sandblasting gun and the contact surface of the curved surface sample is controlled at 90°, and the rest is the same as Example 1.

[0072] With stainless steel as the base, bend the 100×14×2mm (length, width and height) sample stainless steel into a sample with R48mm and thickness of 2mm. Then clean it with alcohol or gasoline; fix the cleaned bent sample on a fixture with R60mm, height: 30mm, wall thickness: 12mm, and the fixture rotates on the turntable at a speed of 80r / min.

[0073] The surface of the curved specimen was activated and roughened with 240 mesh zirconium corundum. The angle between the sand discharged from the sandblasting gun and the surface of the curved specimen was controlled at 90°. The spray gun pressure was 0.2Mpa; the sandblasting distance was 50mm.

[0074] Then, the Mo coating was sprayed on the bending specimen by APS atmospheric plasma spraying technology; the test conditions were: hydrogen: 10 L / h; argon: 40 L / h; current: 430 A; voltage: 100 V; spray distance: 90 mm; powder feeding amount: 35 g / min.

[0075] Comparative Example 2

[0076] The difference between this comparative example and Example 1 is that the fixture rotates on the turntable at a speed of 110 r / min, and the rest is the same as Example 1.

[0077] Comparative Example 3

[0078] The difference between this comparative example and Example 1 is that the angle between the sand outlet of the spray gun and the contact surface of the curved sample is 10°, and the rest is the same as Example 1.

[0079] Comparative Example 4

[0080] The difference between this comparative example and Example 1 is that the spray gun pressure is 0.9 MPa, and the rest is the same as Example 1.

[0081] Comparative Example 5

[0082] The difference between this comparative example and Example 1 is that the spray distance is 120 mm, and the rest is the same as Example 1.

[0083] Comparative Example 6

[0084] The difference between this comparative example and Example 1 is that the hydrogen flow rate is 20 L / min, and the rest is the same as Example 1.

[0085] Comparative Example 7

[0086] The difference between this comparative example and Example 1 is that the voltage is 150V, and the rest is the same as Example 1.

[0087] Comparative Example 8

[0088] The difference between this comparative example and Example 1 is that the powder feeding amount is 60 g / min. The other parts are the same as Example 1.

[0089] Test Case

[0090] The interface contamination of the coatings treated in Examples 1 to 9 and Comparative Examples 1 to 8 was tested using the HB 20195-2016 standard. The bonding strength of the coatings was tested using the C633 standard.

[0091] The micro Vickers hardness of the coating was tested using a micro Vickers hardness tester.

[0092] The test results are shown in Table 1.

[0093] Table 1

[0094]

[0095]

Claims

1. A method for reducing interface contamination of curved surfaces of Mo coatings used for aviation sealing, It is characterized in that The method comprises the following steps: 1) Bend the stainless steel sample into a R47-49mm sample and clean it with alcohol or gasoline, then fix it on the tooling. The fixture rotates on the turntable at a speed of 80-100r / min; 2) Use 240 mesh zirconium corundum to perform surface activation and roughening treatment on the curved sample; the angle between the sand discharged from the sandblasting gun and the contact surface of the curved surface sample is controlled at 20°-40°; the spray gun pressure is 0.15-0.25Mpa; the sand blasting distance is 50-80mm; Alternatively, the surface of the bending sample may be activated and roughened by argon ion polishing, or the surface may be activated and roughened by electrolytic polishing; wherein the argon ion polishing process parameters are: voltage: 3-5Kev, time: 1h, vacuum degree: 3E -5 Pa; electrolytic polishing process parameters: voltage: 25V, time: 60s, current: 0.4-0.6mA, temperature: -10℃; 3) Spraying Mo coating on the bending specimen obtained in step 2) by using APS atmospheric plasma spraying technology, under the following conditions: Hydrogen: 10-12L / h; Argon: 40-45L / h; Current: 430-450A; Voltage: 90-120V; Spray distance: 80-100mm; Powder feeding amount: 30-40g / min.

2. The method for reducing interface contamination of curved surfaces of Mo coatings for aviation sealing according to claim 1, It is characterized in that Step 1) The turntable rotates at a speed of 90 r / min.

3. The method for reducing interface contamination of curved surfaces of Mo coatings for aviation sealing according to claim 1, It is characterized in that Step 2) The nozzle diameter is Φ10mm.

4. The method for reducing interface contamination of curved surfaces of Mo coatings for aviation sealing according to claim 1, It is characterized in that Step 2) The angle between the sand blasting gun muzzle and the contact surface of the curved surface sample is 30°.

5. The method for reducing interface contamination of curved surfaces of Mo coatings for aviation sealing according to claim 1, It is characterized in that Step 2) The spray gun pressure is 0.2Mpa.

6. The method for reducing interface contamination of curved surfaces of Mo coatings for aviation sealing according to claim 1, It is characterized in that Step 2) The sand blowing distance is 60 mm.

7. The method for reducing interface contamination of curved surfaces of Mo coatings for aviation sealing according to claim 1, It is characterized in that On rainy days or when the weather is humid, before step 3), heat treatment is performed on the bending sample at a temperature of 1050-1100°C and a holding time of 3 hours.

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