A modified ceramic particle wear-resistant mending agent and preparation method thereof

Abstract

The present invention relates to a modified ceramic particle wear-resistant repair agent and a preparation method thereof. The wear-resistant repair agent comprises ceramic particles having a pyramidal rough surface and a needle-like morphology formed on the surface of the ceramic particles, thereby increasing the bonding strength between the ceramic particles and the epoxy matrix and achieving an anchoring effect on the ceramic particles. The present invention controls the oxidation temperature to form needle-like aluminum oxide and prismatic oxide films such as nickel oxide and nickel aluminum spinel on the surface of the ceramic particles, thereby increasing the bonding area between the ceramic particles and the epoxy resin and anchoring the ceramic particles through the columnar aluminum oxide, thereby improving the bonding strength of the ceramic particles in the epoxy resin.

Description

Technical Field

[0001] The invention belongs to the field of high-performance wear-resistant mending agents for mechanical equipment, in particular to a modified ceramic particle wear-resistant mending agent and a preparation method thereof. Background Art

[0002] Equipment in the power and chemical industries, often subject to wear and heavy loads, often suffers severe damage. Damage can lead to increased vibration, reduced strength, and compromised safe operation. These damages typically manifest as wear pits and cracks. However, due to the constraints of the equipment's operating conditions, metal repair agents are often used to repair these pits after cracks have been eliminated. The repaired area typically requires wear and corrosion resistance.

[0003] Currently, most commercial repair agents are a combination of ceramic particles added to the epoxy matrix. However, due to the difference in physical properties between the ceramic particles and the epoxy matrix, the bonding strength between them is relatively low, and even gaps exist3, such as Figure 1 As shown, the ceramic particles are easily detached from the epoxy matrix, which makes it unable to fully exert its anti-wear performance. Summary of the Invention

[0004] The present invention aims to overcome the shortcomings of existing patching agents, such as low ceramic particle bonding strength, by providing a modified ceramic particle wear-resistant patching agent and a preparation method. By modifying the ceramic particle surface, a rough, raised surface morphology resembling a lychee shell is formed on the ceramic particle surface, significantly increasing the bonding area between the ceramic particle and the epoxy matrix. Furthermore, the "needle-like" structures extending from the surface can be embedded in the epoxy matrix, preventing the ceramic particles from prematurely falling off. This technology effectively solves the technical problem of premature ceramic particle shedding in existing patching agents.

[0005] The present invention provides a ceramic particle modification method for improving the bonding strength between ceramic particles and epoxy resin matrix. The essence of the method is to attach nano-metal ions to the surface of ceramic particles and, by controlling the oxidation temperature, oxidize the ceramic particles to form needle-like aluminum oxide and prismatic nickel oxide, nickel aluminum spinel and other oxide films on the surface of the ceramic particles, thereby increasing the bonding area between the ceramic particles and the epoxy resin and anchoring the ceramic particles through the columnar aluminum oxide, thereby improving the bonding strength of the ceramic particles in the epoxy resin.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A modified ceramic particle wear-resistant mending agent comprises ceramic particles, the surfaces of which are formed with pyramidal rough surfaces and needle-like morphology, thereby increasing the bonding strength between the ceramic particles and an epoxy matrix and achieving an anchoring effect on the ceramic particles.

[0008] Furthermore, the wear-resistant repair agent includes epoxy resin and ceramic particles included in the epoxy resin. The ceramic particles include columnar aluminum oxide, nickel oxide and nickel aluminum spinel distributed on the surface. The columnar aluminum oxide is thorn-shaped and has a length greater than that of nickel oxide and nickel aluminum spinel.

[0009] The present invention also relates to a method for preparing a modified ceramic particle wear-resistant repair agent, comprising the following steps:

[0010] Step (1) The ceramic particles are placed in acetone or anhydrous ethanol for vibration cleaning to remove dust and dirt on the surface, and then dried at 100°C to 120°C to ensure that the slurry can be better spread on the surface of the ceramic particles, which determines whether the slurry can be spread on the surface of the particles.

[0011] Step (2) preparing an aluminum-nickel slurry, mixing nano-aluminum powder, nano-nickel powder and a water-soluble solvent to form a slurry, wherein the molar ratio of the nano-aluminum powder to the nano-nickel powder is 3:(1-1.5); placing ceramic particles in the prepared slurry, stirring for about 30-40 minutes, so that the surface of the ceramic particles is covered with aluminum powder and nickel powder, and separating the ceramic particles and the aqueous aluminum slurry through a sieve; the ratio of the raw materials is very critical, and the materials determine whether the structural morphology designed by the present invention can be formed after subsequent heat treatment.

[0012] Step 3: The separated ceramic particles are placed in an environment of 700-950°C for heat treatment for 30-240 minutes. This key parameter determines whether needle-shaped and pyramid-shaped morphologies can be formed, so that the aluminum and nickel on the surface are oxidized, and a uniform continuous oxide film with a thickness of 0.5-4μm is formed at the bottom of the oxide layer, which is tightly bonded to the ceramic particles; needle-shaped or columnar aluminum oxide and a pyramid-shaped nickel-aluminum spinel structure are formed on the outer surface, such as Figure 2 shown.

[0013] Furthermore, the ceramic particles are any ceramic material with a melting point higher than 1200° C., including Al 2 O 3 , ZrO 2 , TiO 2 , SiC , and TiC , with a particle size of 200-400 μm.

[0014] Furthermore, in step (1), the sample is placed in acetone or anhydrous ethanol for vibration cleaning.

[0015] Furthermore, in step (1), the removal is followed by drying at 100°C to 120°C.

[0016] Furthermore, in step (2), the particle size of the aluminum powder and the nickel powder is 10 nm to 90 nm.

[0017] Furthermore, the method further includes step (4) adding the modified ceramic particles having needle-shaped and pyramid-shaped surfaces into epoxy and stirring the mixture thoroughly to form a colloid in which the ceramic phase is in full contact with the epoxy.

[0018] The above method can achieve a higher bonding strength between the ceramic phase and the epoxy. The ceramic particles of the present invention have a needle-like and pyramid-like structure on the surface, which greatly increases the bonding area between the ceramic particles and the epoxy. At the same time, the needle-like structure can anchor the ceramic particles.

[0019] In this invention, the key to enhancing the bond strength between ceramic particles and a matrix such as epoxy resin is to create a surface morphology that coexists with both thorny and pyramidal shapes. Achieving this morphology requires careful consideration of the ceramic particle pretreatment, material ratios, and heat treatment parameters. A high-performance repair compound requires strong bonding between the ceramic particles and the epoxy resin. The challenge of this invention lies in designing the ceramic particles to maximize their contact area with the surrounding epoxy resin, preventing them from falling off.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] This invention pioneers a "chestnut shell"-like surface morphology (featuring needle-like and pyramidal morphologies) for ceramic particles, as well as a method for achieving this structure. Conventionally produced ceramic particles have smooth surfaces, resulting in weak adhesion to epoxy resins, which have significantly different properties. This invention improves the bonding strength between ceramic particles and epoxy resins.

[0022] The bonding area between ceramic particles and epoxy is greatly increased, the bonding strength is high, and no holes will appear between ceramic particles and epoxy, eliminating the Figure 1 The figure shows the phenomenon of voids formed by debonding of ceramic particles due to solidification.

[0023] The needle-like structure on the surface of the ceramic particles plays an anchoring role on the ceramic particles, further strengthening the bonding between the ceramic particles and the matrix. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is in the state of ceramic particles of traditional repair agent;

[0025] Figure 2 The surface state of the ceramic particles after modification according to the specific embodiment of the present invention;

[0026] 1-Epoxy resin, 2-Ceramic particles, 3-Voids between ceramic particles and epoxy matrix, 4-Columnar alumina, 5-Nickel oxide and nickel aluminum spinel. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below in conjunction with the examples. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention. In the examples, if no specific techniques or conditions are indicated, they are carried out according to the techniques or conditions described in the literature in this area or according to the product specifications. If the manufacturer of the reagents or instruments is not indicated, they are all conventional products that can be purchased.

[0028] Unless otherwise specified, percentages in this invention represent mass fractions.

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Example 1

[0030] The preparation method of the modified ceramic particle wear-resistant mending agent of this embodiment comprises:

[0031] Al2O3 was used as ceramic particles with a particle size of 200~400μm. The ceramic particles were placed in acetone and placed in an ultrasonic vibration cleaning tank for 10 minutes to remove surface dust and dirt. The ceramic particles were taken out and dried at 100℃ after removal.

[0032] Prepare an aluminum-nickel slurry by thoroughly dispersing nano-aluminum powder, nano-nickel powder, and a water-soluble solvent. The molar ratio of nano-aluminum powder to nano-nickel powder is 3:1, and the particle sizes of the aluminum and nickel powders are between 10 nm and 30 nm. Place ceramic particles in the slurry and stir them magnetically for 30 minutes until the surface of the ceramic particles is fully covered with aluminum and nickel powder. Use a sieve to separate the ceramic particles from the aqueous aluminum slurry.

[0033] The separated ceramic particles are placed in an environment of 800° C. for heat treatment for 120 minutes to oxidize the aluminum and nickel on their surfaces to form needle-shaped or columnar aluminum oxide and a nickel-aluminum spinel structure with a pyramidal morphology.

[0034] like Figure 2 As shown, the wear-resistant repair agent includes epoxy resin 1 and ceramic particles 2 included in the epoxy resin 1. The ceramic particles 2 include columnar aluminum oxide 4, nickel oxide and nickel aluminum spinel 5 distributed on the surface. The columnar aluminum oxide 4 is thorn-shaped and has a length greater than that of nickel oxide and nickel aluminum spinel 5.

[0035] Ceramic particles with needle-shaped and pyramid-shaped surfaces after modification are added to epoxy, where the volume of the ceramic particles accounts for 80%, and are fully stirred to form a colloid in which the ceramic phase is in full contact with the epoxy.

[0036] During application, the metal substrate needs to be roughened to make its surface roughness reach Ra20μm or above, and then the repair agent colloid formed in step (4) is applied to fill the metal pit area. After the application is completed and the surface is kept flat, the area is subjected to high-temperature curing in the range of 50~80℃. The application is completed after high-temperature curing for 30-120 minutes. Example 2

[0037] The preparation method of the modified ceramic particle wear-resistant mending agent of this embodiment comprises:

[0038] ZrO2 is used as ceramic particles with a particle size of 200~400μm. The ceramic particles are placed in acetone and placed in an ultrasonic vibration cleaning tank for 10 minutes to remove surface dust and dirt. The ceramic particles are taken out and dried at 110℃ after removal.

[0039] Prepare an aluminum-nickel slurry by mixing nano-aluminum powder, nano-nickel powder, and a water-soluble solvent. The molar ratio of nano-aluminum powder to nano-nickel powder is 3:1.5, and the particle size of the aluminum and nickel powders is 10nm to 30nm. Place ceramic particles in the prepared slurry and stir them thoroughly using a magnetic stirrer for approximately 35 minutes until the surface of the ceramic particles is fully covered with aluminum and nickel powders. Use a screen to separate the ceramic particles from the aqueous aluminum slurry.

[0040] The separated ceramic particles were heat treated at 950°C for 40 minutes to oxidize the aluminum and nickel on their surfaces to form short columnar aluminum oxide and a large number of pyramidal nickel aluminum spinel structures.

[0041] Ceramic particles with columnar and pyramidal morphologies on the modified surface are added to polyurethane, where the volume of the ceramic particles accounts for 50%, and are fully stirred to form a colloid in which the ceramic phase is in full contact with the polyurethane.

[0042] The application method is the same as in Example 1. Example 3

[0043] The preparation method of the modified ceramic particle wear-resistant mending agent of this embodiment comprises:

[0044] SiC is used as ceramic particles with a particle size of 200~400μm. The ceramic particles are placed in acetone and placed in an ultrasonic vibration cleaning tank for 10 minutes to remove surface dust and dirt. The ceramic particles are taken out and dried at 118℃ after removal.

[0045] Prepare an aluminum-nickel slurry by mixing nano-aluminum powder, nano-nickel powder, and a water-soluble solvent. The molar ratio of nano-aluminum powder to nano-nickel powder is 3:1, and the particle size of the aluminum and nickel powders ranges from 10 nm to 30 nm. Place ceramic particles in the slurry and stir them thoroughly with magnetic stirring for 40 minutes until the surface of the ceramic particles is covered with aluminum and nickel powders. Use a sieve to separate the ceramic particles from the aqueous aluminum slurry.

[0046] The separated ceramic particles were heat treated at 700°C for 240 minutes to oxidize the aluminum and nickel on their surfaces to form needle-shaped or columnar aluminum oxide and a pyramid-shaped nickel-aluminum spinel structure.

[0047] Ceramic particles with needle-shaped and pyramid-shaped surfaces after modification are added to epoxy, where the volume of the ceramic particles accounts for 60%, and are fully stirred to form a colloid in which the ceramic phase is in full contact with the epoxy.

[0048] The application method is the same as in Example 1.

[0049] The following comparative examples illustrate the differences between the effects not within the scope of the present invention and the effects of Examples 1-3.

[0050] Comparative Example 1: The ceramic particles and epoxy matrix phase raw material compositions of this comparative example are the same as those of Example 1, with the only difference being that the ceramic particles are conventional spherical particles, and their surfaces do not have the needle-shaped and pyramidal surface morphologies described in Example 1.

[0051] Comparative Example 2: This comparative example has the same raw material composition as Example 1, except that the ceramic particle pretreatment requirement described in step (1) is not adopted.

[0052] Comparative Example 3: This comparative example has the same raw material composition as Example 1, except that the material ratio exceeds the range of 3: (1-1.5) described in step (2) of claim 1.

[0053] Comparative Example 4: This comparative example has the same raw material composition as that of Example 1, and the material ratio is also in the range of 3: (1~1.5) described in step (2). The only difference is that the aluminum powder and nickel powder do not use the powder particle size range described in step (2).

[0054] Comparative Example 5: This comparative example has the same raw material composition as Example 1, except that the heat treatment temperature is lower than 700°C described in step (3).

[0055] Comparative Example 6: This comparative example has the same raw material composition as Example 1, except that the heat treatment temperature is higher than 950°C described in step (3).

[0056] Comparative Example 7: This comparative example has the same raw material composition as Example 1, with the only difference being that the heat treatment time is shortened to 20 minutes instead of 30 minutes in step (3).

[0057] Comparative Example 8: This comparative example has the same raw material composition as Example 3, with the only difference being that the heat treatment time is longer than 240 minutes in step (3), for example, 270 minutes.

[0058] The results are shown in Table 1:

[0059] Table 1

[0060] ;

[0061] It can be seen that the key steps and core process parameters in the above embodiments are not common knowledge in the art.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a modified ceramic particle wear-resistant mending agent, characterized in that: The steps include: Step (1) placing the ceramic particles in acetone or anhydrous ethanol for vibration cleaning to remove dust and dirt on the surface, and then drying at 100°C to 120°C; Step (2) preparing an aluminum-nickel slurry by mixing nano-aluminum powder, nano-nickel powder, and a water-soluble solvent to form a slurry, wherein the molar ratio of the nano-aluminum powder to the nano-nickel powder is 3:(1-1.5); placing ceramic particles in the prepared slurry and stirring for about 30-40 minutes to allow the surface of the ceramic particles to be covered with aluminum powder and nickel powder, and separating the ceramic particles and the aqueous aluminum slurry through a sieve; Step (3) heat-treating the separated ceramic particles at 700-950°C for 30-240 minutes to oxidize the aluminum and nickel on their surfaces, forming a uniform continuous oxide film with a thickness of 0.5-4 μm at the bottom of the oxide layer, which is tightly bonded to the ceramic particles; forming needle-shaped or columnar aluminum oxide and a pyramid-shaped nickel-aluminum spinel structure on the outer surface, wherein the length of the needle-shaped or columnar aluminum oxide is greater than that of the pyramid-shaped nickel oxide and the nickel-aluminum spinel; Step (4), adding the modified ceramic particles having needle-shaped or columnar alumina and pyramid-shaped nickel aluminum spinel structures on the surface into the epoxy resin and stirring them evenly to form a colloid in which the ceramic phase and the epoxy resin phase are fully in contact, thereby increasing the bonding strength between the ceramic particles and the epoxy resin matrix and achieving an anchoring effect on the ceramic particles; In the step (2), the particle size of the nano-aluminum powder and the nano-nickel powder is 10 nm to 90 nm.

2. The preparation method according to claim 1, wherein: The ceramic particles are any ceramic material with a melting point higher than 1200°C, including Al2O3, ZrO2, TiO2, SiC, TiC, and a particle size of 200~400μm.

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