Method for improving hole sealing effect of DM-4000 hole sealing agent on AT13 ceramic coating through isopropanol dilution

Abstract

The invention discloses a method for improving the hole sealing effect of a DM-4000 hole sealing agent on an AT13 ceramic coating through isopropanol dilution. According to the method, DM-4000 (Dura-Metal Sealer 4000) is diluted by using isopropanol (the ratio of DM-4000 to isopropanol is (1: 0)-(1: 1)), so that the flowability of the DM-4000 is improved, and the hole sealing effect on the AT13 (Al2O3-13% TiO2) ceramic coating is improved. Under the optimal hole sealing parameters (the volume ratio of isopropanol to DM-4000 is 1: 0.5), the maximum hole sealing depth of 400 microns can be obtained, and the overall porosity is reduced from 2.78% to 2.25%. The method is simple in process, low in cost and suitable for large-scale hole sealing requirements.

Description

Technical Field

[0001] The invention belongs to the technical field of surface engineering and coatings, and particularly relates to a method for improving the sealing effect of a DM-4000 sealing agent on an AT13 ceramic coating by diluting the agent with isopropyl alcohol. Background Art

[0002] AT13 ceramic coating, due to its excellent hardness, wear resistance, high temperature resistance and good insulation properties, has shown great value in the application of protective and functional coatings in the fields of aerospace, energy, chemical industry, machinery, etc. However, the existing preparation process of AT13 ceramic coating, such as thermal spraying, often inevitably forms a certain number of pores, microcracks and incompletely melted particles inside and on the surface of the coating. The presence of these microscopic defects significantly affects the overall performance of the coating: (1) Decreased corrosion resistance: The pores and cracks in the coating provide a permeation channel for corrosive media (such as acid, alkali, salt solution or high-temperature gas), allowing the corrosive media to directly contact the substrate material or the inside of the coating, accelerating the corrosion and failure of the material. (2) Decreased wear resistance: Pores and microcracks easily become stress concentration points or sources of wear debris during the wear process, making the coating more prone to peeling or wear, shortening its service life. In order to improve the performance of AT13 ceramic coating, sealing treatment is a common and effective method. DM-4000 sealing agent is a chemical treatment agent widely used to improve the performance of ceramic coatings. Its core function is to fill microscopic defects such as pores and microcracks within the coating, thereby significantly improving the coating's corrosion resistance and wear resistance, thereby enhancing coating reliability and extending its service life. However, when DM-4000 is applied to AT13 ceramic coatings, problems still exist, such as unsatisfactory pore sealing, complex processes, and high costs.

[0003] In existing technologies, researchers have attempted to improve the penetration of the DM-4000 sealer by modifying the coating surface, but this affects the mechanical properties of the coating surface and increases production time and cost. Other researchers have also added other sealers, such as DICHTOL WFT#1532, to DM-4000. However, this addition can easily alter the physical and chemical properties of DM-4000, thereby affecting the sealing effect. Therefore, there is an urgent need to develop a low-cost, highly stable DM-4000 sealing technology for AT13 ceramic coatings that can maximize the preservation of the coating's original properties. Summary of the Invention

[0004] To address the shortcomings of existing technologies, a method for improving the sealing effect of DM-4000 sealant on AT13 ceramic coatings by diluting it with isopropyl alcohol has been proposed. This method aims to improve the sealing effect of AT13 ceramic coatings by diluting DM-4000 with isopropyl alcohol. This method can effectively increase the penetration depth of DM-4000, optimize the sealing effect, and effectively reduce the porosity of the coating, thereby improving the corrosion resistance and lifespan of the AT13 ceramic coating.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] S1: AT13 ceramic coating was prepared on the substrate by plasma spraying using AT13 powder with a particle size of 45-75 μm. The spraying parameters included: current 610 A, argon flow rate 35 nlpm, hydrogen flow rate 8 nlpm, and spraying distance 100 mm. The obtained AT13 ceramic coating had a thickness of 550 μm and a porosity of 2.78%.

[0007] S2: Use a wool brush to apply a sealant diluted with DM-4000 and isopropyl alcohol in a volume ratio of 1:0-1:1 on the AT13 ceramic coating. The sealing parameters include: sealing temperature of 30°C, brushing time of 8 minutes, pre-drying time of 2 hours, and pre-drying temperature of 60°C.

[0008] S3: After drying, polish the surface and repeat the application to complete the second sealing.

[0009] S4: Place the AT13 ceramic coating after the second sealing in a drying oven and dry it at 80°C for 48 hours.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] By adopting a diluted DM-4000 sealing agent, the present invention can significantly reduce the porosity of the AT13 ceramic coating. Under preferred conditions (using a sealing agent diluted at a ratio of 1:0.5), the porosity of the obtained AT13 ceramic coating is reduced from an initial 2.78% to 2.25%, indicating that the pores are effectively filled. The dilution of isopropyl alcohol improves the fluidity of the DM-4000 sealing agent, making it easier to enter smaller pores. Subsequent long-term high-temperature drying ensures that the sealing agent is fully solidified or reacted inside the coating to form a stable sealing structure. These measures work together to not only reduce the porosity, but also are expected to improve the key properties of the coating, such as density, corrosion resistance, and wear resistance, providing an effective and cost-controlled process for obtaining high-performance AT13 ceramic protective coatings. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is the cross-sectional morphology of the AT13 ceramic coating obtained in Examples 1-3 of the present invention.

[0013] Figure 2 3 is a Si element distribution diagram of the cross section of the AT13 ceramic coating obtained in Examples 1-3 of the present invention. DETAILED DESCRIPTION

[0014] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0015] Example 1

[0016] Step S1: Using AT13 powder with a particle size of 45-75 μm as a raw material, an AT13 ceramic coating was prepared on a Q235 steel substrate (diameter 20 mm, thickness 1.5 mm) by plasma spraying. The spraying parameters included: current 610 A, argon flow rate 35 nlpm, hydrogen flow rate 8 nlpm, and spraying distance 100 mm. The obtained AT13 ceramic coating had a thickness of 550 μm and a porosity of 2.78%.

[0017] Step S2: Using a wool brush, apply a sealant prepared by diluting DM-4000 and isopropyl alcohol in a volume ratio of 1:0 on the AT13 ceramic coating. The sealing parameters include: sealing temperature of 30°C, application time of 8 minutes, pre-drying time of 2 hours, and pre-drying temperature of 60°C.

[0018] Step S3: After drying, polish the surface and repeat the brushing once to complete the second sealing;

[0019] Step S4: The AT13 ceramic coating after the second sealing was placed in a drying oven and dried at 80° C. for 48 hours to obtain an AT13 ceramic coating with a porosity of 2.37%.

[0020] Figure 1 The figure corresponding to “1:0” is the cross-sectional morphology of the AT13 ceramic coating obtained in Example 1 of the present invention, with a porosity of 2.37%.

[0021] Figure 2 The corresponding figure of “1:0” is the Si element distribution diagram of the cross section of the AT13 ceramic coating obtained in Example 1 of the present invention, and the penetration depth of the sealing agent is about 300 μm.

[0022] Example 2

[0023] Step S1: Using AT13 powder with a particle size of 45-75 μm as a raw material, an AT13 ceramic coating was prepared on a Q235 steel substrate (diameter 20 mm, thickness 1.5 mm) by plasma spraying. The spraying parameters included: current 610 A, argon flow rate 35 nlpm, hydrogen flow rate 8 nlpm, and spraying distance 100 mm. The obtained AT13 ceramic coating had a thickness of 550 μm and a porosity of 2.78%.

[0024] Step S2: Using a wool brush, apply a sealant prepared by diluting DM-4000 and isopropyl alcohol in a volume ratio of 1:0 on the AT13 ceramic coating. The sealing parameters include: sealing temperature of 30°C, application time of 8 minutes, pre-drying time of 2 hours, and pre-drying temperature of 60°C.

[0025] Step S3: After drying, polish the surface and repeat the brushing once to complete the second sealing;

[0026] Step S4: The AT13 ceramic coating after the second sealing was placed in a drying oven and dried at 80° C. for 48 hours to obtain an AT13 ceramic coating with a porosity of 2.25%.

[0027] Figure 1 The figure corresponding to “1:0.5” is the cross-sectional morphology of the AT13 ceramic coating obtained in Example 2 of the present invention, with a porosity of 2.25%.

[0028] Figure 2 The graph corresponding to “1:0.5” is the Si element distribution diagram of the cross section of the AT13 ceramic coating obtained in Example 2 of the present invention, and the penetration depth of the sealing agent is about 400 μm.

[0029] Example 3

[0030] Step S1: Using AT13 powder with a particle size of 45-75 μm as a raw material, an AT13 ceramic coating was prepared on a Q235 steel substrate (diameter 20 mm, thickness 1.5 mm) by plasma spraying. The spraying parameters included: current 610 A, argon flow rate 35 nlpm, hydrogen flow rate 8 nlpm, and spraying distance 100 mm. The obtained AT13 ceramic coating had a thickness of 550 μm and a porosity of 2.78%.

[0031] Step S2: Using a wool brush, apply a sealant prepared by diluting DM-4000 and isopropyl alcohol in a volume ratio of 1:0 on the AT13 ceramic coating. The sealing parameters include: sealing temperature of 30°C, application time of 8 minutes, pre-drying time of 2 hours, and pre-drying temperature of 60°C.

[0032] Step S4: After drying, polish the surface and repeat the brushing once to complete the second sealing;

[0033] Step S3: The AT13 ceramic coating after the second sealing was placed in a drying oven and dried at 80° C. for 48 hours to obtain an AT13 ceramic coating with a porosity of 2.34%.

[0034] Figure 1 The “1:1” corresponding figure is the cross-sectional morphology of the AT13 ceramic coating obtained in Example 3 of the present invention, with a porosity of 2.34%.

[0035] Figure 2 The “1:1” corresponding figure is the Si element distribution diagram of the cross section of the AT13 ceramic coating obtained in Example 3 of the present invention, and the penetration depth of the sealing agent is about 200 μm.

Claims

1. A method for improving the sealing effect of DM-4000 sealing agent on AT13 ceramic coating by diluting it with isopropyl alcohol, characterized in that: The following steps are involved: (1) Using AT13 powder as raw material, AT13 ceramic coating was prepared on the substrate by plasma spraying method. The spraying parameters included: current 610A, argon flow rate 35nlpm, hydrogen flow rate 8nlpm, and spraying distance 100mm to obtain AT13 ceramic coating; (2) A sealant prepared by diluting DM-4000 and isopropyl alcohol by volume was applied to the AT13 ceramic coating using a wool brush. The sealing parameters included: sealing temperature 30°C, application time 8 min, and pre-drying for 2 h. (3) After drying, polish the surface and repeat the brushing once to complete the second sealing; (4) The AT13 ceramic coating after the second sealing was placed in a drying oven and dried at 80°C for 48 hours.

2. The method according to claim 1, characterized in that The substrate in step (1) is Q235 steel.

3. The method according to claim 1, characterized in that The volume ratio of the DM-4000 and isopropanol diluted in step (2) is 1:0-1:1, and the purity of the isopropanol is 99.9%.

4. The method according to claim 1, wherein The pre-drying temperature in step (2) is 60°C.

5. An AT13 ceramic coating sealed according to the method of any one of claims 1 to 4.

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