A coating with high wear resistance, preparation method and centrifugal pump obtained

Abstract

The present invention discloses a coating with high wear resistance, a preparation method and a centrifugal pump, which belongs to the technical field of coating preparation. The coating comprises the following components in weight percentage: 40-50% Ni-based self-fluxing alloy powder, 40-50% cast tungsten carbide powder, WC 13 Co alloy powder (5-15%), with the balance being YG alloy, is used. The coating produced by this invention significantly improves the hardness and wear resistance of the eroded areas of the centrifugal pump body and pump cover. Even in operating conditions characterized by severe particle erosion and wear in conveying media, such as those encountered in powder metallurgy and mining, the service life of the centrifugal pump can be extended to 4-6 times that of conventional high-chromium cast iron centrifugal pumps.

Description

Technical Field

[0001] The invention belongs to the technical field of coating preparation, and in particular relates to a coating with high wear resistance, a preparation method and a centrifugal pump prepared therefrom. Background Art

[0002] Centrifugal pumps operate by generating centrifugal motion in the fluid medium through the rotation of the impeller. In specific operating conditions, when the liquid medium contains relatively hard particles, these particles, under the influence of pressure and speed, can cause severe erosion and wear on the pump body, leading to wear through the pump body and leakage failure. To address the wear resistance issue of centrifugal pumps, the current common solution is to use high-chromium cast iron or other wear-resistant materials. However, the wear resistance of existing technical solutions still needs to be further improved in conditions such as powder metallurgy and mining where particle erosion and wear in the transmission medium are more severe.

[0003] The pump body and pump cover of a centrifugal pump are relatively complex structures. Wear-resistant protection for the inner surfaces of the pump body and pump cover also requires consideration of factors such as material hardness, bonding strength, and ease of preparation. Currently, wear-resistant technical solutions for centrifugal pumps can be divided into the following categories: 1. Nitriding the wear-resistant parts of the centrifugal pump (example: CN109236661B); 2. Spraying a hard alloy coating on the wear-resistant parts of the centrifugal pump (example: CN110257754A); 3. Installing wear-resistant blocks between the impeller and the pump casing, and applying wear-resistant mortar on the inner wall of the pump head housing (example: CN209053793U); 4. Adding a polymer composite silicon carbide ceramic lining to the wear-resistant parts of the centrifugal pump (example: CN108204367A).

[0004] While the aforementioned technologies can improve the protection of centrifugal pumps to a certain extent, they still have the following shortcomings: For example, the hardness and wear resistance of the first nitriding solution cannot meet the requirements of high-erosion wear conditions; the bonding strength and coating thickness (generally 0.3-0.5mm) of the second thermal spray carbide coating solution cannot meet the requirements of high-erosion wear conditions; the third wear-resistant block and wear-resistant mortar solution lack operational reliability, and the protective layer is prone to falling off; the fourth silicon carbide ceramic lining solution has a complex structure, poor toughness, and cracking during melting. Therefore, it is crucial to design a coating that meets the working conditions and has excellent wear resistance. Summary of the Invention

[0005] In view of the above-mentioned deficiencies in the prior art, the present invention provides a coating with high wear resistance, a preparation method and a centrifugal pump prepared thereby, which can effectively improve the wear resistance of working parts, such as a centrifugal pump.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the present invention to solve the technical problem is:

[0007] A coating with high wear resistance comprises the following components in weight percentages:

[0008] Ni-based self-fluxing alloy powder 40-50%, cast tungsten carbide powder 40-50%, WC 13 Co alloy powder 5-15%, the balance is YG alloy.

[0009] Further, the following components are included in weight percentage:

[0010] Ni-based self-fluxing alloy powder 45-50%, cast tungsten carbide powder 45-50%, WC 13 Co alloy powder 5-10%, the balance is YG alloy.

[0011] Furthermore, Ni-based self-fluxing alloy powder 48-50%, cast tungsten carbide powder 48-50%, WC 13 Co alloy powder 5-8%, the balance is YG alloy.

[0012] Furthermore, the particle size of the Ni-based self-fluxing alloy powder is 60-200 meshes.

[0013] Furthermore, the particle size of the cast tungsten carbide powder is 40-80 meshes.

[0014] Furthermore, WC 13 The particle size of the Co alloy powder is 100 to 325 mesh.

[0015] Furthermore, the YG alloy has a particle size of 2 to 8 mm and includes at least one of YG6, YG8, YG9 and YG12.

[0016] Furthermore, the YG alloy includes YG6 and YG12 in a mass ratio of 1:2 to 3.

[0017] A method for preparing the coating comprises mixing the components uniformly according to a formula, sintering at 900-1050° C. for 15-30 minutes to solidify and form the coating.

[0018] A high-wear-resistant centrifugal pump has a pump body and a pump cover inner cavity wall of the centrifugal pump fixed with the above-mentioned coating with high wear-resistant performance.

[0019] Beneficial effects of the present invention:

[0020] This application adds YG alloy particles with good toughness to the formula, and adds cast tungsten carbide with high hardness and wear resistance, and supplemented with fine particles of WC 13 Co crushes the alloy and effectively fills the weak gaps between large hard particles. The final result is a nickel-based self-fluxing alloy as the bonding phase, large particles of YG alloy and cast tungsten carbide as the main skeleton, and small particles of WC 13The microstructure of the Co crushed alloy is a small abrasive particle, which gives the new wear-resistant coating extremely high strength, erosion resistance and wear resistance.

[0021] The coating prepared by the present invention can significantly improve the hardness and wear resistance of the erosion parts of the centrifugal pump body and pump cover. Even under working conditions where particle erosion and wear are relatively severe in the transmission medium such as powder metallurgy and mining, the service life of the centrifugal pump can be increased to 4-6 times the service life of a centrifugal pump made of conventional high chromium cast iron. DETAILED DESCRIPTION

[0022] The specific embodiments of the present invention are described below to facilitate understanding of the present invention by those skilled in the art. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the appended claims, these changes are obvious, and all inventions and creations utilizing the concepts of the present invention are protected.

[0023] Example 1

[0024] A coating with high wear resistance comprises the following components in weight percentages:

[0025] 100 mesh Ni-based self-fluxing alloy powder 45%, 80 mesh casting tungsten carbide powder 40%, 100 mesh WC 13 Co alloy powder is 6%, and the balance is 4mm YG alloy, wherein the YG alloy includes YG6 and YG12 with a mass ratio of 1:2.

[0026] Example 2

[0027] A coating with high wear resistance comprises the following components in weight percentages:

[0028] 60 mesh Ni-based self-fluxing alloy powder 50%, 80 mesh casting tungsten carbide powder 50%, 200 mesh WC 13 5% Co alloy powder, the balance is 2mm YG alloy, wherein the YG alloy includes YG6 and YG12 with a mass ratio of 1:3.

[0029] Example 3

[0030] A coating with high wear resistance comprises the following components in weight percentages:

[0031] 200 mesh Ni-based self-fluxing alloy powder 40%, 40 mesh casting tungsten carbide powder 40%, 160 mesh WC 13 Co alloy powder is 15%, and the balance is 8mm YG alloy, wherein the YG alloy includes YG6 and YG12 with a mass ratio of 1:2.

[0032] Comparative Example 1

[0033] Compared with Example 1, the formula lacks YG6, and the other components are the same as those in Example 1.

[0034] Comparative Example 2

[0035] Compared with Example 1, the formula lacks WC 13 Co alloy, and the other components are the same as those in Example 1.

[0036] Comparative Example 3

[0037] Compared with Example 1, the nickel-based self-fluxing alloy in the formula is replaced by a cobalt-based alloy, and the other components are the same as those in Example 1.

[0038] Comparative Example 4

[0039] Compared with Example 1, the nickel-based self-fluxing alloy in the formula is replaced by cobalt-based alloy, and the WC in the formula is replaced by VC-Co cemented carbide. 13 Co alloy, and the other components are the same as those in Example 1.

[0040] Experimental example

[0041] The coatings obtained in Example 1 and Comparative Examples 1 to 4 were used to prepare a high-wear-resistant centrifugal pump. The specific process is as follows:

[0042] 1. Make a sand mold cavity according to the size of the centrifugal pump body and pump cover.

[0043] 2. After mixing all the components evenly according to the formula, sinter at 900-1050℃ for 15-30 minutes to ensure that the sintered body is solidified.

[0044] 3. Fix the sintered mixed material block on the inner wall of the sand cavity of the pump body and pump cover, and heat the cavity.

[0045] 4. After deoxidation treatment, the molten wear-resistant steel is poured into the mold cavity for integral casting.

[0046] 5. Perform mechanical processing on relevant positions to meet assembly requirements.

[0047] After the production was completed, the wear amount was tested using an abrasive wear tester, and a conventional high-chromium cast iron sample was used as a control. The results are shown in Table 1.

[0048] Table 1 Wear amount

[0049]

[0050] According to the data in Table 1, the wear resistance of the wear-resistant coating prepared by the technical solution of the present application is 3.15 times higher than that of the conventional high-chromium cast iron sample, and the wear resistance is greatly improved. Compared with Comparative Examples 1 and 2, due to the lack of some components in the formula, it is not complete compared with the technical solution of the present application. Its wear resistance is not only not comparable to the technical solution of the present application, but also does not have a significant advantage in wear resistance compared with the conventional high-chromium cast iron sample, indicating that it does not have excellent wear resistance. Comparative Examples 3 and 4 use cobalt-based alloys and VC-Co cemented carbides to replace the nickel-based self-fluxing alloy and WC 13 The coating formed by the Co alloy has a certain wear resistance, but it is still 2 to 3 times lower than that of the present application. It can be seen that only with the combination of the components in the technical solution of the present application can a coating with excellent wear resistance be prepared, which can extend the service life of the centrifugal pump by 4 to 6 times.

[0051] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A coating with high wear resistance, characterized in that: The composition comprises the following components in weight percentage: Ni-based self-fluxing alloy powder 40-50%, cast tungsten carbide powder 40-50%, WC 13 Co alloy powder 5-15%, the balance is YG alloy; The particle size of the Ni-based self-fluxing alloy powder is 60-200 mesh; the particle size of the cast tungsten carbide powder is 40-80 mesh; 13 The particle size of the Co alloy powder is 100-325 mesh; the particle size of the YG alloy is 2-8 mm, including at least one of YG6, YG8, YG9 and YG12; The coating is prepared by uniformly mixing various components according to a formula, and sintering at 900-1050° C. for 15-30 minutes to solidify and form the coating.

2. The coating according to claim 1, characterized in that The composition comprises the following components in weight percentage: Ni-based self-fluxing alloy powder 45-50%, cast tungsten carbide powder 45-50%, WC 13 Co alloy powder 5-10%, the balance is YG alloy.

3. The coating according to claim 1 or 2, characterized in that The composition comprises the following components in weight percentage: Ni-based self-fluxing alloy powder 48-50%, cast tungsten carbide powder 48-50%, WC 13 Co alloy powder 5-8%, the balance is YG alloy.

4. The coating according to claim 1, characterized in that YG alloy includes YG6 and YG12 with a mass ratio of 1:2 to 3.

5. A high wear-resistant centrifugal pump, characterized in that: The coating with high wear resistance according to any one of claims 1 to 4 is fixed on the inner cavity wall of the pump body and pump cover of the centrifugal pump.

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