Preparation method and application of composite super-hydrophobic surface
By designing a composite surface combining graded micro/nanostructures with porous structures, the surface is manufactured and processed using selective laser melting and picosecond laser technology, and forming a nanoparticle coating through ultrasonic spraying, the problem of poor mechanical durability of superhydrophobic surfaces in abrasive environments is solved, and superhydrophobicity and prolong service life under mechanical wear conditions are achieved.
Patent Information
- Application Number
- CN202510067689.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-16
- Publication Date
- 2025-05-27
AI Technical Summary
The existing superhydrophobic surface has poor mechanical durability in abrasive environment, resulting in loss of superhydrophobicity, and lack of systematic research and cost-effective manufacturing processes, resulting in poor wear resistance.
By designing a composite surface combining graded micro/nanostructures and porous structures, using three-dimensional modeling software to design the surface model, selective laser melting to create porous metal substrates, combined with picosecond laser technology to precision process the microstructure, and ultrasonic spraying to form a nanoparticle coating to build a composite superhydrophobic surface.
It achieves the maintenance of superhydrophobicity under mechanical wear conditions, extends service life, and maintains excellent waterproofing performance.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of hydrophobic materials, and particularly to a preparation method and application of a composite superhydrophobic surface. Background Art
[0002] Due to their excellent water-repellent properties (contact angle > 150° and sliding angle < 10°), superhydrophobic surfaces have shown broad application prospects in multiple fields such as self-cleaning systems, anti-corrosion coatings, and liquid manipulation technologies. These surfaces achieve a stable air-water interface through the synergistic effect of low-surface-energy materials and hierarchical micro / nano-scale surface structures. However, the mechanical durability of superhydrophobic surfaces in practical applications has become a key factor restricting their widespread use. Especially in abrasive environments, the surface structure is easily damaged, resulting in the loss of superhydrophobicity. To address this issue, existing research has proposed a composite surface design strategy that combines hierarchical micro / nano structures with porous materials. Due to their inherent energy dissipation ability and structural adaptability, porous materials can effectively reduce the impact of mechanical forces and extend the service life of superhydrophobic surfaces. However, there is currently a lack of systematic research on the interaction between surface porosity, hierarchical structure, and wear resistance, and there is also a lack of a scalable, cost-effective manufacturing process, resulting in the inability of related technologies to meet the actual application requirements, and the problem of poor wear resistance of superhydrophobic surfaces being widespread in the existing technology. Therefore, how to develop a new type of composite superhydrophobic surface to improve the wear resistance of superhydrophobic surfaces is an urgent problem to be solved currently. Summary of the Invention
[0003] Aiming at the technical problems existing in the prior art, the first object of the present invention is to provide a preparation method of a composite superhydrophobic surface. By designing a composite surface combining hierarchical micro / nano structures and porous structures, the wear resistance and mechanical durability of the superhydrophobic surface are improved, while maintaining its excellent water-repellent properties.
[0004] The second object of the present invention is to provide a composite superhydrophobic surface obtained by the above preparation method.
[0005] The third object of the present invention is to provide an application of the above composite superhydrophobic surface.
[0006] To achieve the above objects, the present invention adopts the following technical solutions:
[0007] A preparation method of a composite superhydrophobic surface, comprising the following steps:
[0008] (1) Preparation of a porous metal substrate: Use three-dimensional modeling software to design a surface model with a porous structure and hierarchical microstructures, import the surface model into a selective laser melting device, and use metal powder as the raw material to manufacture a metal substrate with a porous structure according to the printing parameters;
[0009] (2) Precision machining of the microstructure of the porous metal substrate: cleaning, drying and laser processing the porous metal substrate to form a microstructure on the surface of the porous metal substrate;
[0010] (3) Coating spraying: spraying the nanoparticle solution on the surface of the microstructure of the porous metal substrate to form a nanoparticle coating, and completing the construction of the composite superhydrophobic surface.
[0011] Further, in step (1), the porous metal substrate is prepared by the following method in the selective laser melting equipment: the printing platform of the selective laser melting equipment descends to the initial position, and the feeding platform and the scraper are adjusted to the preset positions; by raising the printing platform and operating the scraper to evenly spread the metal powder on the printing platform to form a uniform layer of metal powder; based on the preset printing parameters, using a laser beam to selectively melt the metal powder layer according to the preset scanning path to form a layer of porous structure; repeating the above operations and stacking layer by layer until the printing of the porous metal substrate is completed.
[0012] Further, in step (1), the metal powder is 316 stainless steel; the printing parameters of the selective laser melting equipment include the contour speed, the filling speed, the contour power, the filling power, the filling spacing and the offset. Among them, the contour speed is 360±20 m / s, the filling speed is 1000±300 m / s, the contour power is 180±20 W, the filling power is 70±20 W, the filling spacing is 0.07±0.02 mm, and the offset is 0.07±0.02 mm. Preferably, the contour speed is 360 m / s, the filling speed is 1000 m / s, the contour power is 180 W, the filling power is 80 W, the filling spacing is 0.07 mm, and the offset is 0.07 mm.
[0013] Further, in step (2), the microstructure formed on the surface of the porous metal substrate is prepared based on picosecond laser technology, and the method is as follows: placing the porous metal substrate in anhydrous ethanol and deionized water successively, and performing ultrasonic cleaning respectively. After cleaning, it is dried for standby; placing the porous metal substrate on the laser processing platform, and regulating the laser processing parameters and selecting the processing method to form a microstructure on the surface of the porous metal substrate.
[0014] Further, the processing parameters include grid spacing, number of scans, laser power, laser scanning frequency, and laser scanning speed. Among them, the grid spacing is 5 - 15 microns, the number of scans is 5 - 15 times, the laser power is 1.48 - 3.7 W, the laser scanning frequency is 50 - 200 KHz, and the laser scanning speed is 200 - 600 mm / s; the processing method is grid type, and the laser reciprocally scans along the x-axis and y-axis directions of the laser processing platform. Preferably, the grid spacing is 5 microns, the number of scans is 15 times, the laser power is 1.48 W, the laser scanning frequency is 200 KHz, and the laser scanning speed is 600 mm / s.
[0015] Further, the nanoparticle solution is superhydrophobic SiO 2 nanoparticle solution.
[0016] Further, the superhydrophobic SiO 2 nanoparticle solution is prepared by the following method:
[0017] a) Mix perhydropolysilazane with dibutyl ether at a concentration of 20 ± 5 wt%, and further dilute it to a concentration of 0.125 ± 0.025 wt% to obtain a perhydropolysilazane / dibutyl ether solution;
[0018] b) Mix 1H,1H,2H,2H-perfluorodecyltriethoxysilane with a hexane solution to form a 1H,1H,2H,2H-perfluorodecyltriethoxysilane / hexane solution;
[0019] c) Disperse SiO 2 spheres with a diameter of 80 - 500 nm into the 1H,1H,2H,2H-perfluorodecyltriethoxysilane / hexane solution obtained in step b) at a concentration of 0.5 ± 0.25 wt%. The mixing time is 1 ± 0.5 hours, and the obtained mixture is dried in an oven at 120 ± 20 °C for 2 ± 1 hours to obtain modified SiO 2 dry powder;
[0020] d) Add the modified SiO 2 dry powder obtained in step c) and the perhydropolysilazane / dibutyl ether solution obtained in step a) into an ethanol solution to form a 1 ± 0.5 wt% SiO 2 / ethanol solution;
[0021] e) Stir the SiO 2 / ethanol solution in step d) at a speed of 1500 ± 200 rpm for 2 ± 1 hours to obtain a superhydrophobic SiO 2 nanoparticle solution.
[0022] Further, the superhydrophobic SiO2 The nanoparticle solution is spray-coated onto the microstructured surface of the porous metal substrate by ultrasonic spraying to form a nanoparticle coating. Among them, the spraying air pressure is 0.015 ± 0.005 Mpa, the nozzle height is 50 ± 10 mm, the spraying width is 4 ± 2 mm, the scanning speed is 100 ± 20 mm / s, and the spraying times are 15 ± 5 times; preferably, the spraying air pressure is 0.015 Mpa, the nozzle height is 50 mm, the spraying width is 4 mm, the scanning speed is 100 mm / s, and the spraying times are 15 times.
[0023] Furthermore, the 3D modeling software is Solidworks or CAD.
[0024] A composite superhydrophobic surface is obtained by the above preparation method.
[0025] The application of the above composite superhydrophobic surface in self-cleaning surfaces, anti-corrosion surfaces, and liquid manipulation surfaces.
[0026] The present invention has the following advantages:
[0027] In the present invention, the surface is structurally designed using Solidworks software to form a model with hierarchical pores and microstructures. Through the selective laser melting (SLM) additive manufacturing technology, the designed structure is fabricated into a porous metal substrate. Using the picosecond laser technology, the surface of the substrate is precisely engraved with microstructures to achieve hierarchical micro / nano-scale textures. Then, through the ultrasonic spraying method, a binary SiO 2 nanoparticle is coated on the microstructured surface to form a superhydrophobic coating, thereby obtaining a composite superhydrophobic surface. The present invention combines the characteristics of hierarchical micro / nano structures and porous materials, and can maintain superhydrophobicity under mechanical wear conditions and extend the service life. Description of the Drawings
[0028] Figure 1 It is a three-dimensional structural schematic diagram of the surface model with a porous structure and hierarchical microstructures designed using 3D modeling software in the present invention.
[0029] Figure 2 It is a surface morphology diagram of the composite superhydrophobic surface of the present invention, showing the uniformity of the coating and the distribution of hierarchical micro / nano structures. Among them, (a) shows the surface morphology diagram of the porous metal substrate after printing by the selective laser melting equipment, (b) shows the surface morphology diagram of the microstructures formed on the surface of the porous metal substrate after precision machining, and (c) shows the surface morphology diagram of the superhydrophobic surface after coating spraying.
[0030] Figure 3 It is a schematic diagram of the surface contact angle of Example 1 of the present invention.
[0031] Figure 4This is a surface morphology image of the composite super-hydrophobic surface of Comparative Example 1.
[0032] Figure 5 It is a schematic diagram of the process of manufacturing a porous metal substrate using a selective laser melting device and processing a microstructure using a picosecond laser in the present invention.
[0033] Figure 6 It is a schematic diagram of the process of coating spraying of the present invention. DETAILED DESCRIPTION
[0034] The present invention is further described in detail below in conjunction with the examples, but the embodiments of the present invention are not limited thereto. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art. The test methods for which specific experimental conditions are not specified in the following examples are generally carried out under conventional experimental conditions. Unless otherwise specified, the reagents and raw materials used in the present invention can be obtained commercially. The perhydropolysilazane used in the examples was purchased from Jining Benock Biotechnology Co., Ltd., and dibutyl ether, SiO 2 The balls, FAS-17, and ethanol were purchased from Aladdin.
[0035] Example 1
[0036] This embodiment provides a method for preparing a composite super-hydrophobic surface, and the specific preparation steps are as follows:
[0037] Preparation of porous metal substrate: A surface model with a porous structure and a hierarchical microstructure was designed using Solidworks 3D modeling software, and the designed model was imported into the selective laser melting (SLM) equipment. 316 stainless steel material was used as the metal powder raw material, and the SLM technology was used to manufacture a metal substrate with a porous structure. The specific operation method was to first clean the surface of the Zhongrui 160 printer, place the loose porous metal substrate on the printing platform, then lower the printing platform to the initial position, and adjust the feeding platform and the scraper to the preset position; then raise the platform, operate the scraper to move left to spread the powder, and Operate the scraper to evenly spread the metal powder on the printing platform to form a uniform metal powder layer; based on the preset printing parameters, use the laser beam to selectively melt the metal powder layer according to the preset scanning path to form a porous structure; repeat the above operations, stack layer by layer, and finally sinter each layer. By adjusting the printer at a lower power density, a substrate with a porous structure can be obtained, wherein the profile speed is 360mm / s, the filling speed is 1000mm / s, the profile power is 180W, the filling power is 70W, the filling spacing is 0.07mm, and the offset is 0.07mm.
[0038] Precision machining of the microstructure of porous metal substrates: First, place the porous metal substrates in anhydrous ethanol and deionized water successively for ultrasonic cleaning for 15 minutes, and then put them into a drying oven for drying for later use to remove the dirt on the surface. Using picosecond laser technology, place the porous metal substrates on the laser processing platform, control the variables of the processing platform, adjust the grid spacing to 5 microns, the number of scanning times to 5 times, the laser power to 1.48 W, the laser scanning frequency to 50 KHz, and the laser scanning speed to 200 mm / s. At the same time, control other relevant parameters to remain unchanged for laser processing. The selected processing method is grid type, and the laser scans in the x-axis and y-axis directions in a reciprocating manner. After the laser processing is completed, the sample needs to be cleaned and dried again and subjected to oxygen ion treatment to form a microstructure on the surface of the porous metal substrate.
[0039] Coating spraying: Dilute 20 wt% of perhydropolysilazane (PHPS) with dibutyl ether to 0.125 wt% to obtain a perhydropolysilazane / dibutyl ether solution. Mix 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane with a hexane solution to form a 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane / hexane solution. Disperse SiO 2 spheres with a diameter of 80 nm in a 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (FAS-17) / hexane solution at 0.5 wt% and soak for 1 hour, and dry in an oven at 120 °C for 2 hours to obtain modified SiO 2 dry powder. Next, add the modified SiO 2 dry powder and the perhydropolysilazane / dibutyl ether solution to an ethanol solution to obtain a 1 wt% SiO 2 / ethanol solution. Then, stir at 1500 rpm for 2 hours to obtain a superhydrophobic SiO 2 nanoparticle solution. Through the ultrasonic spraying method: the spraying air pressure is 0.015 Mpa, the nozzle height is 50 mm, the spraying width is 4 mm, the scanning speed is 100 mm / s, and the spraying times are 15 times. Uniformly spray the SiO 2 nanoparticle suspension on the microstructure surface of the porous metal substrate to form a nanoparticle coating and complete the construction of the superhydrophobic surface.
[0040] Surface property analysis: The surface topography was analyzed by a surface topography microscope (SEM / laser confocal), then its surface composition was calibrated (SRF), and finally the contact angle of the surface was measured using a water droplet contact angle measuring instrument (OSA200T-P1). The results showed that the contact angle of the superhydrophobic surface was 153.5° which is greater than 150°, and the sliding angle was 4.25° which is less than 10°, proving its excellent superhydrophobic performance. Then, a friction and wear test was carried out. After 250 physical frictions with a 100g weight, the contact angle was 149.9°. The results indicated that the surface could still maintain stable hydrophobicity under mechanical wear conditions.
[0041] Example 2
[0042] This example provides a preparation method for a composite superhydrophobic surface. The specific preparation steps are as follows:
[0043] Preparation of a porous metal substrate: A surface model with a porous structure and a hierarchical microstructure was designed using Solidworks 3D modeling software. The designed model was imported into a selective laser melting (SLM) device. Using 316 stainless steel material as the metal powder raw material, a metal substrate with a porous structure was fabricated using the SLM technology. The specific operation method was to first clean the surface of the Zhongrui 160 printer, place the porous metal substrate on the printing platform, then lower the printing platform to the initial position, and adjust the powder feeding platform and the scraper to the preset positions; then raise the platform, operate the scraper to move left for powder spreading, and operate the scraper to evenly spread the metal powder on the printing platform to form a uniform layer of metal powder; based on the preset printing parameters, use a laser beam to selectively melt the metal powder layer according to the preset scanning path to form a porous structure; repeat the above operations for layer-by-layer stacking, and finally sinter each layer. By adjusting the printer at a relatively low power density, a substrate with a porous structure could be obtained. Among them, the contour speed was 360 mm / s, the filling speed was 1250 mm / s, the contour power was 180 W, the filling power was 80 W, the filling spacing was 0.07 mm, and the offset was 0.07 mm.
[0044] Precision machining of the microstructure of porous metal substrates: First, place the porous metal substrates in anhydrous ethanol and deionized water successively for ultrasonic cleaning for 15 minutes, and then put them into a drying oven for drying for later use to remove the dirt on the surface. Using picosecond laser technology, place the porous metal substrates on the laser processing platform, control the variables of the processing platform, adjust the grid spacing to 10 micrometers, the number of scanning times to 10 times, the laser power to 2.45 W, the laser scanning frequency to 100 KHz, and the laser scanning speed to 400 mm / s. At the same time, control other relevant parameters to remain unchanged for laser processing. The selected processing method is grid type, and the laser scans in a reciprocating manner in the x-axis and y-axis directions respectively. After the laser processing is completed, the sample needs to be cleaned and dried again and subjected to oxygen ion treatment to form a microstructure on the surface of the porous metal substrate.
[0045] Coating spraying: Dilute 20 wt% of perhydropolysilazane (PHPS) with dibutyl ether to 0.125 wt% to obtain a perhydropolysilazane / dibutyl ether solution. Mix 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane with a hexane solution to form a 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane / hexane solution. Disperse SiO spheres with a diameter of 500 nm at 0.5 wt% into a 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (FAS-17) / hexane solution and soak for 1 hour, and dry in an oven at 120 °C for 2 hours to obtain modified SiO dry powder. Next, add the modified SiO dry powder and the perhydropolysilazane / dibutyl ether solution to an ethanol solution to obtain a 1 wt% SiO / ethanol solution. Then, stir at 1500 rpm for 2 hours to obtain a superhydrophobic SiO nanoparticle solution. Through the ultrasonic spraying method: the spraying air pressure is 0.02 Mpa, the nozzle height is 50 mm, the spraying width is 4 mm, the scanning speed is 100 mm / s, and the spraying times are 10 times. Uniformly spray the SiO nanoparticle suspension on the microstructure surface of the porous metal substrate to form a nanoparticle coating and complete the construction of the superhydrophobic surface. 2 balls are dispersed in a 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (FAS-17) / hexane solution at 0.5 wt% and soaked for 1 hour, and dried in an oven at 120 °C for 2 hours to obtain modified SiO 2 dry powder. Next, add the modified SiO 2 dry powder and the perhydropolysilazane / dibutyl ether solution to an ethanol solution to obtain a 1 wt% SiO 2 / ethanol solution. Then, stir at 1500 rpm for 2 hours to obtain a superhydrophobic SiO 2 nanoparticle solution. Through the ultrasonic spraying method: the spraying air pressure is 0.02 Mpa, the nozzle height is 50 mm, the spraying width is 4 mm, the scanning speed is 100 mm / s, and the spraying times are 10 times. Uniformly spray the SiO 2 nanoparticle suspension on the microstructure surface of the porous metal substrate to form a nanoparticle coating and complete the construction of the superhydrophobic surface.
[0046] Surface property analysis: The surface topography was analyzed by a surface topography microscope (SEM / laser confocal), and then its surface composition was calibrated (SRF). The contact angle of the surface was measured using a water droplet contact angle measuring instrument (OSA200T-P1). The results showed that the contact angle of the superhydrophobic surface was 154.4°, which was greater than 150°, and the sliding angle was 3.52°, which was less than 10°, proving its excellent superhydrophobic performance. Then, a friction and wear test was carried out. After 250 physical frictions with a 100 g weight, the contact angle was 148.2°. The results showed that the surface could still maintain stable hydrophobicity under mechanical wear conditions.
[0047] Example 3
[0048] This example provides a method for preparing a composite superhydrophobic surface. The specific preparation steps are as follows:
[0049] Preparation of a porous metal substrate: A surface model with a porous structure and a hierarchical microstructure was designed using Solidworks 3D modeling software. The designed model was imported into a selective laser melting (SLM) device. Using 316 stainless steel material as the metal powder raw material, a metal substrate with a porous structure was manufactured by the SLM technology. The specific operation method was to first clean the surface of the Zhongrui 160 printer, place the porous metal substrate on the printing platform, then lower the printing platform to the initial position, and adjust the powder feeding platform and the scraper to the preset positions; then raise the platform, operate the scraper to move left to spread the powder, and operate the scraper to evenly spread the metal powder on the printing platform to form a uniform layer of metal powder; based on the preset printing parameters, use a laser beam to selectively melt the metal powder layer according to the preset scanning path to form a porous structure; repeat the above operations for layer-by-layer stacking, and finally sinter each layer. By adjusting the printer at a relatively low power density, a substrate with a porous structure could be obtained, where the contour speed was 360 mm / s, the filling speed was 1000 mm / s, the contour power was 180 W, the filling power was 80 W, the filling spacing was 0.07 mm, and the offset was 0.07 mm.
[0050] Precision machining of the microstructure of porous metal substrates: First, place the porous metal substrates in anhydrous ethanol and deionized water successively and ultrasonically clean them for 15 min. Then, put them into a drying oven to dry for later use to remove the surface contaminants. Using picosecond laser technology, place the porous metal substrates on the laser processing platform, control the variables of the processing platform, regulate the grid spacing to 5 microns, the number of scanning times to 15 times, the laser power to 1.48 W, the laser scanning frequency to 200 KHz, and the laser scanning speed to 600 mm / s. At the same time, control other relevant parameters to remain unchanged for laser processing. The selected processing method is grid type, and the laser scans in a reciprocating manner in the x-axis and y-axis directions respectively. After the laser processing is completed, the samples need to be cleaned and dried again and treated with oxygen ions to form a microstructure on the surface of the porous metal substrates.
[0051] Coating spraying: Dilute 20 wt% of perhydropolysilazane (PHPS) with dibutyl ether to 0.125 wt% to obtain a perhydropolysilazane / dibutyl ether solution. Mix 1H,1H,2H,2H-perfluorodecyltriethoxysilane with a hexane solution to form a 1H,1H,2H,2H-perfluorodecyltriethoxysilane / hexane solution. Disperse SiO spheres with diameters of 500 nm and 80 nm mixed at a ratio of 1:1 in a 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FAS-17) / hexane solution at 0.5 wt% and soak for 1 hour, and then dry in an oven at 120 °C for 2 hours to obtain modified SiO dry powder. Next, add the modified SiO dry powder and the perhydropolysilazane / dibutyl ether solution to an ethanol solution to obtain a 1 wt% SiO / ethanol solution. Then, stir at 1500 rpm for 2 h to obtain a superhydrophobic SiO nanoparticle solution. Through the ultrasonic spraying method: the spraying air pressure is 0.015 Mpa, the nozzle height is 50 mm, the spraying width is 4 mm, the scanning speed is 100 mm / s, and the spraying times are 15 times. Uniformly spray the SiO nanoparticle suspension on the microstructure surface of the porous metal substrates to form a nanoparticle coating and complete the construction of the superhydrophobic surface. 2 balls at 0.5 wt% and soak for 1 hour, and dry in an oven at 120 °C for 2 hours to obtain modified SiO 2 dry powder. Next, add the modified SiO 2 dry powder and the perhydropolysilazane / dibutyl ether solution to an ethanol solution to obtain a 1 wt% SiO 2 / ethanol solution. Then, stir at 1500 rpm for 2 h to obtain a superhydrophobic SiO 2 nanoparticle solution. Through the ultrasonic spraying method: the spraying air pressure is 0.015 Mpa, the nozzle height is 50 mm, the spraying width is 4 mm, the scanning speed is 100 mm / s, and the spraying times are 15 times. Uniformly spray the SiO 2 nanoparticle suspension on the microstructure surface of the porous metal substrates to form a nanoparticle coating and complete the construction of the superhydrophobic surface.
[0052] Surface property analysis: The surface topography was analyzed by a surface topography microscope (SEM / laser confocal), and then its surface composition was calibrated (SRF). The contact angle of the surface was measured using a water droplet contact angle measuring instrument (OSA200T-P1). The results showed that the contact angle of the superhydrophobic surface was 160.6°, which was greater than 150°, and the sliding angle was 2.45°, which was less than 10°, proving its excellent superhydrophobic performance. Then, a friction and wear test was carried out. After physical friction with a 100 g weight for 250 times, the contact angle was 151.1°. The results showed that the surface could still maintain stable hydrophobicity under mechanical wear conditions.
[0053] Example 4
[0054] This example provides a method for preparing a composite superhydrophobic surface. The specific preparation steps are as follows:
[0055] Preparation of a porous metal substrate: A surface model with a porous structure and a hierarchical microstructure was designed using Solidworks 3D modeling software. The designed model was imported into a selective laser melting (SLM) device. Using 316 stainless steel material as the metal powder raw material, a metal substrate with a porous structure was fabricated by SLM technology. The specific operation method was to first clean the surface of the Zhongrui 160 printer, place the porous metal substrate on the printing platform, then lower the printing platform to the initial position, and adjust the powder feeding platform and the scraper to the preset positions; then raise the platform, operate the scraper to move left to spread the powder, and operate the scraper to evenly spread the metal powder on the printing platform to form a uniform layer of metal powder; based on the preset printing parameters, use a laser beam to selectively melt the metal powder layer according to the preset scanning path to form a layer of porous structure; repeat the above operations for layer-by-layer stacking, and finally sinter each layer. By adjusting the printer at a relatively low power density, a substrate with a porous structure could be obtained, where the contour speed was 360 mm / s, the filling speed was 1000 mm / s, the contour power was 180 W, the filling power was 80 W, the filling spacing was 0.09 mm, and the offset was 0.09 mm.
[0056] Precision machining of the microstructure of porous metal substrates: First, place the porous metal substrates in anhydrous ethanol and deionized water successively for ultrasonic cleaning for 15 minutes, and then put them into a drying oven for drying for later use to remove surface contaminants. Using picosecond laser technology, place the porous metal substrates on the laser processing platform, control the variables of the processing platform, adjust the grid spacing to 15 micrometers, the number of scanning times to 15 times, the laser power to 3.7 W, the laser scanning frequency to 200 KHz, and the laser scanning speed to 600 mm / s. At the same time, control other relevant parameters to remain unchanged for laser processing. The selected processing method is grid type, and the laser scans in a reciprocating manner in the x-axis and y-axis directions respectively. After the laser processing is completed, the sample needs to be cleaned and dried again and treated with oxygen ions to form a microstructure on the surface of the porous metal substrate.
[0057] Coating spraying: Dilute 20 wt% of perhydropolysilazane (PHPS) with dibutyl ether to 0.125 wt% to obtain a perhydropolysilazane / dibutyl ether solution. Mix 1H,1H,2H,2H-perfluorodecyltriethoxysilane with a hexane solution to form a 1H,1H,2H,2H-perfluorodecyltriethoxysilane / hexane solution. Mix SiO 2 spheres with diameters of 500 nm and 80 nm in a ratio of 1:4 and disperse them in a 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FAS-17) / hexane solution at 0.5 wt% for 1 hour, and dry them in an oven at 120 °C for 2 hours to obtain modified SiO 2 dry powder. Next, add the modified SiO 2 dry powder and the perhydropolysilazane / dibutyl ether solution to an ethanol solution to obtain a 1 wt% SiO 2 / ethanol solution. Then, stir at 1500 rpm for 2 hours to obtain a superhydrophobic SiO 2 nanoparticle solution. Through the ultrasonic spraying method: the spraying air pressure is 0.015 Mpa, the nozzle height is 50 mm, the spraying width is 4 mm, the scanning speed is 100 mm / s, and the spraying number is 10 times. Uniformly spray the SiO 2 nanoparticle suspension on the microstructure surface of the porous metal substrate to form a nanoparticle coating, and complete the construction of the superhydrophobic surface.
[0058] Surface performance analysis: The surface topography was analyzed by a surface topography microscope (SEM / laser confocal), and then its surface composition was calibrated (SRF). The contact angle of the surface was measured using a water droplet contact angle measuring instrument (OSA200T-P1). The results showed that the contact angle of the superhydrophobic surface was 152.0°, greater than 150°, and the sliding angle was 3.54°, less than 10°, proving its excellent superhydrophobic performance. Then, a friction and wear test was carried out. After physical friction with a 100 g weight for 250 times, the contact angle was 149.5°. The results showed that the surface could still maintain stable hydrophobicity under mechanical wear conditions.
[0059] Comparative Example 1
[0060] This comparative example provides a method for preparing a composite superhydrophobic surface. The specific preparation steps are as follows:
[0061] Preparation of porous metal substrate: A surface model with a porous structure and hierarchical microstructure was designed using Solidworks 3D modeling software. The designed model was imported into a selective laser melting (SLM) device. Using 316 stainless steel material as the metal powder raw material, a porous metal substrate was manufactured by SLM technology. The specific operation method was to first clean the surface of the Zhongrui 160 printer, then lower the printing platform to the initial position, and adjust the feeding platform and the scraper to the preset positions; then raise the platform, operate the scraper to move left to spread the powder, and operate the scraper to evenly spread the metal powder on the printing platform to form a uniform layer of metal powder; based on the preset printing parameters, use a laser beam to selectively melt the metal powder layer according to the preset scanning path to form a porous structure; repeat the above operations for layer-by-layer stacking, and finally sinter each layer. By adjusting the printer at a relatively low power density, a substrate with a porous structure can be obtained, where the contour speed is 360 mm / s, the filling speed is 1000 mm / s, the contour power is 180 W, the filling power is 60 W, the filling spacing is 0.07 mm, and the offset is 0.07 mm.
[0062] Precision machining of the microstructure of the porous metal substrate: First, the porous metal substrate was successively placed in anhydrous ethanol and deionized water for ultrasonic cleaning for 15 min, and then placed in a drying oven for drying for later use to remove surface contaminants. Using picosecond laser technology, the porous metal substrate was placed on the laser processing platform, the variables of the processing platform were controlled, the grid spacing was regulated to 25 microns, the number of scans was 5 times, the laser power was 6.17 W, the laser scanning frequency was 300 KHz, and the laser scanning speed was 600 mm / s. At the same time, other relevant parameters were controlled to remain unchanged for laser processing. The selected processing method was grid type, and the laser scanned in a reciprocating manner in the x-axis and y-axis directions respectively. After the laser processing, the sample needed to be cleaned and dried again and subjected to oxygen ion treatment, as Figure 4As shown, it was found that its surface was charred. The reason for the charring was the low printing energy density and high laser power, which prevented the formation of microstructures on its surface. Energy density = laser power / (scanning speed * scanning line distance * layer thickness).
[0063] Coating spraying: 20 wt% of perhydropolysilazane (PHPS) was further diluted with dibutyl ether to 0.125 wt% to obtain a perhydropolysilazane / dibutyl ether solution. 1H,1H,2H,2H-perfluorodecyltriethoxysilane was mixed with a hexane solution to form a 1H,1H,2H,2H-perfluorodecyltriethoxysilane / hexane solution. SiO spheres with a diameter of 500 nm were dispersed at 0.5 wt% in a 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FAS-17) / hexane solution and soaked for 1 hour, and then dried in an oven at 120 °C for 2 hours to obtain modified SiO dry powder. 2 Next, the modified SiO dry powder and the perhydropolysilazane / dibutyl ether solution were added to an ethanol solution to obtain a 1 wt% SiO / ethanol solution. Then, after stirring at 1500 rpm for 2 h, a superhydrophobic SiO nanoparticle solution was obtained. By the ultrasonic spraying method: the spraying air pressure was 0.015 Mpa, the nozzle height was 50 mm, the spraying width was 4 mm, the scanning speed was 100 mm / s, and the spraying times were 15 times. The SiO nanoparticle suspension was evenly sprayed on the microstructured surface of the porous metal substrate to form a nanoparticle coating, completing the construction of the superhydrophobic surface. 2 2 2 2 2 nanoparticle suspension to form a nanoparticle coating, completing the construction of the superhydrophobic surface.
[0064] Surface property analysis: The surface morphology was analyzed by a surface morphology microscope (SEM / laser confocal), and then its surface composition was calibrated (SRF). The contact angle of the surface was measured using a water droplet contact angle measuring instrument (OSA200T-P1). The results showed that the contact angle of the superhydrophobic surface was 129.5°, greater than 150°, and the sliding angle was 24.55°, less than 10°, proving that it did not have superhydrophobic properties; a friction and wear test was carried out. After physical friction with a 100 g weight for 250 times, the contact angle was 91.1°. The results showed that the surface was unstable under mechanical wear conditions.
[0065] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.
Claims
1. A method for preparing a composite super-hydrophobic surface, characterized in that: The following steps are involved: (1) Preparation of porous metal substrate: using 3D modeling software to design a surface model with a porous structure and a hierarchical microstructure, importing the surface model into a selective laser melting device, using metal powder as a raw material, and manufacturing a metal substrate with a porous structure according to printing parameters; (2) Precision processing of the microstructure of the porous metal substrate: cleaning, drying and laser processing the porous metal substrate to form a microstructure on the surface of the porous metal substrate; (3) Coating spraying: spraying the nanoparticle solution onto the microstructure surface of the porous metal substrate to form a nanoparticle coating, thereby completing the construction of the composite super-hydrophobic surface.
2. A method for preparing a composite super-hydrophobic surface according to claim 1, characterized in that: In step (1), the porous metal substrate is prepared in the selective laser melting device by the following method: the printing platform of the selective laser melting device is lowered to an initial position, and the feeding platform and the scraper are adjusted to a preset position; the metal powder is evenly spread on the printing platform by raising the printing platform and operating the scraper to form a uniform metal powder layer; based on the preset printing parameters, the metal powder layer is selectively melted by a laser beam according to a preset scanning path to form a porous structure; the above operation is repeated, and the layers are stacked layer by layer until the printing of the porous metal substrate is completed.
3. A method for preparing a composite super-hydrophobic surface according to claim 1, characterized in that: In step (1), the metal powder is 316 stainless steel; the printing parameters of the selective laser melting equipment include profile speed, fill speed, profile power, fill power, fill spacing and offset, wherein the profile speed is 360±20m / s, the fill speed is 1000±300m / s, the profile power is 180±20W, the fill power is 70±20W, the fill spacing is 0.07±0.02mm, and the offset is 0.07±0.02mm.
4. A method for preparing a composite super-hydrophobic surface according to claim 1, characterized in that: In step (2), the microstructure formed on the surface of the porous metal substrate is prepared based on picosecond laser technology, and the method is as follows: the porous metal substrate is placed in anhydrous ethanol and deionized water in turn, and ultrasonically cleaned respectively, and then dried for standby use after cleaning; the porous metal substrate is placed on a laser processing platform, and the laser processing parameters are adjusted and the processing method is selected to form a microstructure on the surface of the porous metal substrate.
5. A method for preparing a composite super-hydrophobic surface according to claim 4, characterized in that: The processing parameters include grid spacing, number of scans, laser power, laser scanning frequency and laser scanning speed, wherein the grid spacing is 5-15 microns, the number of scans is 5-15 times, the laser power is 1.48-3.7W, the laser scanning frequency is 50-200KHz, and the laser scanning speed is 200-600mm / s; the processing method is grid type, and the laser scans back and forth along the x-axis and y-axis directions of the laser processing platform respectively.
6. A method for preparing a composite super-hydrophobic surface according to claim 1, characterized in that: The nanoparticle solution is a super-hydrophobic SiO2 nanoparticle solution.
7. A method for preparing a composite super-hydrophobic surface according to claim 6, characterized in that: The super-hydrophobic SiO2 nanoparticle solution is prepared by the following method: a) mixing perhydropolysilazane with dibutyl ether at a concentration of 20±5 wt %, and further diluting the mixture to a concentration of 0.125±0.025 wt %, to obtain a perhydropolysilazane / dibutyl ether solution; b) mixing 1H,1H,2H,2H-perfluorodecyltriethoxysilane with the hexane solution to form a 1H,1H,2H,2H-perfluorodecyltriethoxysilane / hexane solution; c) mixing and dispersing SiO2 spheres with a diameter of 80-500 nm into the 1H,1H,2H,2H-perfluorodecyltriethoxysilane / hexane solution obtained in step b) at a concentration of 0.5±0.25wt% for 1±0.5 hours, and drying the obtained mixture in an oven at 120±20°C for 2±1 hours to obtain a modified SiO2 dry powder; d) adding the modified SiO2 dry powder obtained in step c) and the perhydropolysilazane / dibutyl ether solution obtained in step a) to an ethanol solution to form a 1±0.5 wt% SiO2 / ethanol solution; e) stirring the SiO2 / ethanol solution of step d) at a rotation speed of 1500±200 rpm for 2±1 hours to obtain a super hydrophobic SiO2 nanoparticle solution.
8. A method for preparing a composite super-hydrophobic surface according to claim 6, characterized in that: The super-hydrophobic SiO2 nanoparticle solution is ultrasonically sprayed onto the microstructure surface of the porous metal substrate to form a nanoparticle coating, wherein the spraying pressure is 0.015±0.005Mpa, the nozzle height is 50±10mm, the spraying width is 4±2mm, the scanning speed is 100±20mm / s, and the number of spraying times is 15±5 times.
9. A composite super-hydrophobic surface, characterized in that: The method is obtained by the preparation method described in any one of claims 1 to 8.
10. Use of the composite super-hydrophobic surface according to claim 9 in self-cleaning surfaces, anti-corrosion surfaces and liquid manipulation surfaces.