Preparation method of explosion spraying wear-resistant and corrosion-resistant coating of thin-wall W-shaped sealing ring

Abstract

The invention belongs to the technical field of thermal spraying, and particularly relates to a preparation method of a wear-resistant and corrosion-resistant coating for explosion spraying of a thin-wall W-shaped sealing ring. CoMo alloy is adopted as a binding phase, carbide is adopted as a wear-resistant phase, the high-temperature fuel gas corrosion resistance and the high-temperature wear-resistant lubricating performance of the coating are remarkably improved, the temperature bearing capacity can reach 800 DEG C or above, and the service life of the W-shaped sealing ring is greatly prolonged. A low-speed explosion spraying and high-speed explosion spraying combined process method is adopted, deformation damage to the thin-wall part in the traditional sand blasting pretreatment process is avoided, the wear resistance and corrosion resistance of the coating are remarkably improved, and meanwhile the implementation process is simple and convenient, high in reliability and low in cost; the follow-up tool is adopted as a support, the deformation problem of the thin-wall part in the spraying process is remarkably reduced, the functions of stabilizing the part profile and reducing the internal stress of a coating are achieved through the shaping treatment technology, the overall deformation of the part is smaller than or equal to 5%, and the problem of spraying deformation of the thin-wall W sealing part is thoroughly solved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of thermal spraying technology, and particularly relates to a method for preparing an explosion-sprayed wear-resistant and corrosion-resistant coating of a thin-wall W-type seal ring. BACKGROUND

[0002] The W-type seal ring is a new self-tightening metal seal ring, which obtains sealing capacity by relying on the elastic reaction force of itself and the pressure of the sealing medium, and simultaneously compensates and buffers the axial separation displacement of the sealing end surface caused by frictional wear, axial separation and vibration, etc. The W-type seal ring is widely used at present between the rotor of a turbine and the casing of an aero-engine. The W-type seal ring is generally made of a nickel-based metal material, and the wall thickness thereof is usually about 0.2-0.5 mm. Since the W-type seal ring works for a long time in a high-temperature corrosive, sliding friction and reciprocating deformation environment, the component is prone to wear, thereby causing leakage. Therefore, it is urgent to develop an advanced high-temperature protective coating for the surface of the thin-wall W-type seal ring, so as to play the functions of high-temperature resistance, wear resistance and gas corrosion resistance. SUMMARY

[0003] The present application aims at overcoming the deficiencies of the prior art, and provides a method for preparing a thin-wall W-type seal ring protective coating with high-temperature resistance, wear resistance and gas corrosion resistance.

[0004] To achieve the above-mentioned application purposes, the technical solution of the present application is as follows:

[0005] A method for preparing an explosion-sprayed wear-resistant and corrosion-resistant coating of a thin-wall W-type seal ring, which comprises the following steps:

[0006] (1) The side surface of the thin-wall W-type seal ring is scrubbed with industrial acetone or alkaline cleaning agent, and the surface is dried with compressed air and then used; (2) the non-sprayed side of the W-type seal ring is supported with a profiled tooling; (3) the side surface of the seal ring is roughened by using a low-speed explosion spraying process with a multi-rib type powder as a roughening medium, and the roughened surface roughness satisfies Ra3.2-4.0; (4) within 10 minutes after the roughening treatment, a wear-resistant and corrosion-resistant coating is prepared by using a high-speed explosion spraying process, and the coating thickness is 0.05-0.20 mm; (5) the W-type seal ring is subjected to a shaping treatment at a temperature of 150-500; (6) the surface of the coating is subjected to a shaping and grinding treatment by using a shaping and grinding rod and grinding material, and the surface roughness of the coating satisfies Ra1.6-3.2; and (7) the profiled tooling is removed, and the deformation of the W-type seal ring is less than or equal to 5%.

[0007] The CoMo alloy is CoMoCr or CoMoSi or a mixture of the two.

[0008] The carbide is one or a mixture of several of molybdenum carbide, chromium carbide, cobalt carbide.

[0009] The multi-rib type powder is prepared by a melting crushing process, and is prepared by using one or a mixture of several of powder materials such as aluminum oxide, silicon oxide, tungsten carbide, and chromium carbide, and the powder particle size satisfies 30-60 mu m.

[0010] The low-speed explosion spraying process is that the particle velocity is 250-300 m / s, and the W type sealing ring base temperature is 150-200 DEG C.

[0011] The high-speed explosion spraying roughening process is that the particle velocity is 550-600 m / s, and the W type sealing ring base temperature is 100-150 DEG C.

[0012] The profiled tooling is made of high-temperature alloy, and the profiled tooling and the W type sealing ring form complete lamination, and the maximum gap size is less than or equal to 0.2 mm.

[0013] The grinding rod is cast iron material; the abrasive is diamond abrasive paste, and the particle size is 5-30 mu m.

[0014] The explosion spraying process needs to use a mechanical hand to carry a spray gun, and oxygen, acetylene and propane are used as fuel.

[0015] The application has the advantages and beneficial effects, the application adopts an explosion spraying process to prepare a wear-resistant and corrosion-resistant coating according to the structural characteristics of the thin-walled and easily deformed W type sealing ring, plays the functions of high-temperature resistance, wear resistance and combustion gas corrosion resistance, and solves the problem of W type sealing ring spraying deformation.

[0016] 1) CoMo alloy is used as a binder phase, and carbide is used as a wear-resistant phase, wherein the addition of the CoMo alloy can significantly improve the high-temperature combustion gas corrosion resistance and wear-resistant and lubricating functions of the coating, the temperature resistance capacity can reach more than 800 DEG C, the carbide has high hardness and high stability, significantly improves the high-temperature wear resistance of the coating, and greatly prolongs the service life of the W type sealing ring.

[0017] 2), a process method of low-speed explosion spraying and high-speed explosion spraying is used, the deformation damage of the traditional sand blasting pretreatment process to the thin-walled part is solved, the low-speed explosion spraying plays the roles of roughening the spraying surface and preheating the base, the high-speed explosion spraying process can obtain a coating with high density and high bonding strength, significantly improves the wear resistance and corrosion resistance of the coating, and the implementation process is simple, reliable and low in cost.

[0018] 3) Adopting the profiled tooling as support, the deformation problem of the thin-walled part in the spraying process is significantly reduced, and then the profiled treatment process plays a role in stabilizing the part surface and reducing the coating internal stress, the overall deformation of the part is ≤5%, and the problem of spraying deformation of the thin-walled W sealing part is completely solved. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 W sealing ring schematic diagram. DETAILED DESCRIPTION

[0020] The following description does not limit the present application.

[0021] The present application is further described in detail below in conjunction with the embodiments. It should be understood that the preparation method described in the embodiments of the present application is only used to illustrate the present application, and is not a limitation on the present application. Simple improvement of the preparation method of the present application under the premise of the concept of the present application belongs to the scope of the present application.

[0022] A kind of thin-walled W type sealing ring explosion spraying wear-resistant and corrosion-resistant coating preparation method, a kind of protective coating is prepared on the surface of thin-walled W sealing ring, the coating is composed of 30%~60% CoMo alloy and 40%~70% carbide, the specific preparation process includes the following steps:

[0023] (1) adopt industrial acetone or alkaline cleaning agent to scrub the thin-walled W sealing ring spraying side surface, adopt compressed air to dry the surface, and then wait for use;(2) adopt profiled tooling to support the non-spraying side of W type sealing ring;(3) use multi-rib powder as roughening medium, adopt low-speed explosion spraying process to roughen the surface of the sealing ring spraying side, the roughness of the roughened surface meets Ra3.2 μm~Ra4.0 μm;(4) within 10 minutes after roughening treatment, adopt high-speed explosion spraying process to prepare wear-resistant and corrosion-resistant coating, the coating thickness is 0.05~0.20 mm;(5) profiled treatment is carried out on the W type sealing ring, the treatment temperature is 150℃~500℃;(6) the surface of the coating is processed by forming and grinding, the coating surface is processed by using forming and grinding rod and grinding material, the roughness of the coating surface meets Ra1.6 μm~Ra3.2 μm;(7) remove the profiled tooling, the deformation of W type sealing ring is ≤5%.

[0024] The CoMo alloy is CoMoCr or CoMoSi or a mixture of the two.

[0025] The carbide is one or a mixture of several of molybdenum carbide, chromium carbide, cobalt carbide.

[0026] The multi-rib powder is prepared by melting and crushing process, and is prepared by using one or a mixture of several of powder materials such as alumina, silica, tungsten carbide, chromium carbide, and the powder particle size meets 30~60 μm.

[0027] The low-speed explosion spraying process is that the particle velocity is 250-300 m / s, and the W-type sealing ring base temperature is 150-200℃.

[0028] The high-speed explosion spraying roughening process is that the particle velocity is 550-600 m / s, and the W-type sealing ring base temperature is 100-150℃.

[0029] The profiled tooling is made of high-temperature alloy, and the profiled tooling and the W-type sealing ring form complete adhesion, and the maximum gap size is ≤0.2 mm.

[0030] The grinding rod is cast iron material; the abrasive is diamond abrasive paste, and the particle size is 5-30 μm.

[0031] The explosion spraying process needs to use a mechanical hand to carry a spray gun, and oxygen, acetylene and propane are used as fuel.

[0032] Example 1

[0033] As shown in Figure 1 , a W-type sealing ring with a wall thickness of 0.3 mm is selected, and a high-temperature-resistant, wear-resistant and anti-gas corrosion protective coating is prepared on the surface of the thin-walled W-type sealing ring. The coating is prepared by explosion spraying process, and the coating is composed of 40% CoMo alloy and 60% carbide. The specific preparation process is as follows:

[0034] 1) The thin-walled W-type sealing ring spraying side surface is scrubbed with industrial acetone or alkaline cleaning agent, and the surface is dried with compressed air and then used;

[0035] 2) The W-type sealing ring non-spraying side is supported by a profiled tooling, and the tooling material is GH4169 alloy. The gap between the profiled tooling and the W-type sealing ring is 0.06 mm.

[0036] 3) The low-speed explosion spraying process is used to roughen the surface of the sealing ring spraying side with multi-pronged alumina powder as the roughening medium, and the powder particle size is 30-60 μm. After roughening, the surface roughness Ra is 3.6 μm. The low-speed explosion spraying process parameters are as follows: oxygen fuel ratio 1.6, distance 200 mm, particle velocity 287 m / s, and base temperature 185℃.

[0037] 4) After 10 minutes of roughening treatment, the high-speed explosion spraying process is used to prepare a wear-resistant and corrosion-resistant coating, and the coating thickness is 0.15 mm. The high-speed explosion spraying process parameters are as follows: oxygen fuel ratio 1.1, distance 300 mm, particle velocity 580 m / s, and base temperature 125℃.

[0038] 5) The W-type sealing ring is shaped and treated at a temperature of 250℃.

[0039] 6) The surface of the coating is shaped and ground, a shaped grinding rod is used to grind the surface of the coating, the material of the grinding rod is cast iron, the grinding agent is diamond grinding agent, the particle size is 15 μm, and the surface roughness meets Ra 2.8 μm;

[0040] 7) After removing the profiled tool, the W seal ring is checked for deformation of 1%, the coating hardness is 650 HV, the bonding strength is 72 MPa, the coating porosity is 0.89%, and the coating has no peeling and cracking after 30 times of water quenching at 750°C.

[0041] The obtained coating performance is as follows:

[0042]

[0043] Example 2

[0044] A W-shaped seal ring with a wall thickness of 0.5 mm is selected, and a high-temperature-resistant, wear-resistant and anti-gas corrosion protective coating is prepared on the surface of the thin-walled W-shaped seal ring. The coating is prepared by explosion spraying process, and the coating is composed of 50% CoMo alloy and 50% carbide. The specific preparation process is as follows:

[0045] 1) The sprayed side surface of the thin-walled W-shaped seal ring is scrubbed with industrial acetone or alkaline cleaning agent, and the surface is dried with compressed air before use;

[0046] 2) The non-sprayed side of the W-shaped seal ring is supported by a profiled tool, the tool material is GH907 alloy, and the maximum gap between the tool and the W-shaped seal ring is 0.10 mm;

[0047] 3) A multi-ribbed silicon oxide powder is used as a roughening medium, the powder particle size is 30-60 μm, and a low-speed explosion spraying process is used to roughen the sprayed side surface of the seal ring. The surface roughness after roughening is Ra 3.6 μm, and the low-speed explosion spraying process parameters are: oxygen-fuel ratio 1.75, distance 200 mm, particle velocity 250 m / s, and substrate temperature 200°C;

[0048] 4) After roughening for 10 minutes, a wear-resistant and corrosion-resistant coating is prepared by high-speed explosion spraying process, the coating thickness is 0.12 mm, and the high-speed explosion spraying process parameters are: oxygen-fuel ratio 1.2, distance 320 mm, particle velocity 600 m / s, and substrate temperature 125°C;

[0049] 5) The W-shaped seal ring is shaped and treated at a temperature of 150°C;

[0050] 6) The surface of the coating is shaped and ground, a shaped grinding rod is used to grind the surface of the coating, the material of the grinding rod is cast iron, the grinding agent is diamond grinding agent, the particle size is 30 μm, and the surface roughness meets Ra 3.2 μm;

[0051] 7) After removing the profiled tooling, the W seal ring deformation was 1.8%, the coating hardness was 628 HV, the bonding strength was 75 MPa, the coating porosity was 0.65%, and the coating had no peeling or cracking after 30 times of water quenching at 750 °C.

[0052] The obtained coating performance was as follows:

[0053]

Claims

1. A method for preparing a thin-walled W-shaped sealing ring by explosive spraying of a wear-resistant and corrosion-resistant coating, characterized in that, A protective coating is prepared on the surface of a thin-walled W-type sealing ring. The coating consists of 30%–60% CoMo alloy and 40%–70% carbides. The specific preparation process includes the following steps: (1) The sprayed side surface of the thin-walled W sealing ring is wiped with industrial acetone or alkaline cleaning agent and dried with compressed air before use; (2) The non-sprayed side of the W sealing ring is supported by conformal tooling; (3) The sprayed side surface of the sealing ring is roughened by low-speed explosive spraying process using multi-faceted powder as roughening medium, and the surface roughness after roughening meets Ra3.2μm~Ra4.0μm; (4) Within 10 minutes after roughening, wear-resistant and corrosion-resistant coating is prepared by high-speed explosive spraying process, with a coating thickness of 0.05~0.20mm; (5) The W sealing ring is shaped and treated at a temperature of 150℃~500℃; (6) The coating surface is shaped and ground by using a shaped grinding rod and abrasive to grind the coating surface, and the surface roughness of the coating meets Ra1.6μm~Ra3.2μm; (7) Remove the conformal tooling, and the deformation of the W-type sealing ring is ≤5%.

2. The method for preparing a thin-walled W-type sealing ring by explosive spraying of a wear-resistant and corrosion-resistant coating according to claim 1, characterized in that, The CoMo alloy is CoMoCr or CoMoSi or a mixture of both.

3. The method for preparing a thin-walled W-type sealing ring by explosive spraying of a wear-resistant and corrosion-resistant coating according to claim 1, characterized in that, The carbide is one or a mixture of several of molybdenum carbide, chromium carbide, and cobalt carbide.

4. The method for preparing a thin-walled W-type sealing ring by explosive spraying of a wear-resistant and corrosion-resistant coating according to claim 1, characterized in that, The polygonal powder is prepared by a melt crushing process and is made from one or a mixture of powder materials such as alumina, silicon oxide, tungsten carbide, and chromium carbide, with a powder particle size of 30-60 μm.

5. The method for preparing a thin-walled W-type sealing ring by explosive spraying of a wear-resistant and corrosion-resistant coating according to claim 1, characterized in that, The low-speed explosive spraying process is as follows: the particle velocity is 250 m / s to 300 m / s, and the substrate temperature of the W-type sealing ring is 150℃ to 200℃.

6. The method for preparing a thin-walled W-type sealing ring by explosive spraying of a wear-resistant and corrosion-resistant coating according to claim 1, characterized in that, The high-speed explosive spray roughening process is as follows: the particle velocity is 550 m / s to 600 m / s, and the substrate temperature of the W-type sealing ring is 100℃ to 150℃.

7. The method for preparing a thin-walled W-type sealing ring by explosive spraying of a wear-resistant and corrosion-resistant coating according to claim 1, characterized in that, The conformal tooling is made of high-temperature alloy and fits perfectly with the W-shaped sealing ring, with a maximum gap size of ≤0.2mm.

8. The method for preparing a thin-walled W-type sealing ring by explosive spraying of a wear-resistant and corrosion-resistant coating according to claim 1, characterized in that, The grinding rod is made of cast iron; the abrasive is diamond abrasive paste with a particle size of 5μm to 30μm.

9. The method for preparing a thin-walled W-type sealing ring by explosive spraying of a wear-resistant and corrosion-resistant coating according to claim 1, characterized in that, The aforementioned explosive spraying process requires the use of a robotic arm to carry the spray gun, and uses oxygen, acetylene, and propane as fuel.

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