Nanosecond laser processing method and clamp for super-hydrophobic surface of superfine metal wire

Abstract

The invention discloses a nanosecond laser machining method and clamp for the super-hydrophobic surface of a superfine metal wire, and the nanosecond laser machining method for the super-hydrophobic surface of the superfine metal wire comprises the steps that the superfine metal wire is cut into the required length, then the surface of the superfine metal wire is polished through abrasive paper, and then deionized water is used for ultrasonic cleaning and blow-drying; clamping the pretreated superfine metal wire on a clamp; nanosecond laser with the wavelength of 1064 nm, the repetition frequency of 20 kHz, the pulse duration of 100 ns and the light spot diameter of about 50 microns is adopted for etching the superfine metal wire, and the nanosecond laser machining parameters are as follows: the power is 3-15 W, the scanning speed is 300-700 mm / s, and the scanning frequency is 1-5 times; and soaking the superfine metal wire subjected to laser processing in a fluorosilane ethanol solution, and then drying the superfine metal wire. According to the method, the super-hydrophobic structure on the surface of the superfine metal wire is machined, the machining quality is guaranteed, meanwhile, the method is simple, the cost is low, the material universality is good, toxic substances and gas are not generated, and environmental pollution is small.

Description

Technical Field

[0001] The invention relates to the technical field of material surface treatment, and in particular to a nanosecond laser processing method and a fixture for the super-hydrophobic surface of an ultra-fine metal wire. Background Art

[0002] Ultrafine metal wires with a diameter of less than 500 microns have important application prospects in the fields of drag reduction, anti-fouling, anti-icing, oil-water separation, etc. However, the small diameter and cylindrical outer contour shape make it difficult to process. Currently, only a few methods can process hydrophobic surfaces on ultrafine metal wires. Zhang et al. used acidic ferric chloride solution to chemically etch copper wire to construct a microstructure, and then used octadecyl mercaptan to modify and reduce the surface energy, and finally obtained a super-hydrophobic surface with a contact angle of 151° (Journal of Chromatography A, 2022, 1670: 462948.). Wang et al. first used a 90° hydrothermal method to prepare zinc oxide nanorod arrays on the surface of stainless steel wire mesh, and then immersed them in a polydimethylsiloxane solution to reduce the surface energy, and obtained a super-hydrophobic stainless steel wire mesh (ACS Applied Materials & Interfaces, 7 (47), 2015: 26184-26194.). Song et al. used a one-step electrospray method to directly construct a super-hydrophobic coating on the surface of a metal wire (Marine Pollution Bulletin, 2016, 113 (1-2): 211-215.). Liu et al. first arranged polystyrene microspheres with a diameter of 1 micron on the surface of a copper wire to form a microsphere array template, then deposited copper in the gaps of the microsphere array by electrochemical deposition, and finally used tetrahydrofuran to dissolve the microsphere array template to leave a copper microstructure, thereby obtaining a hydrophobic surface (Langmuir, 2022, 38 (8): 2711-2719.). Although the above method can process super-hydrophobic surfaces on ultrafine metal wires, there are still problems such as complex process, high cost, poor material versatility, large environmental pollution, and low processing efficiency. Summary of the invention

[0003] The present invention provides a nanosecond laser processing method and a fixture for super-hydrophobic surface of an ultra-fine metal wire to solve the above-mentioned problem.

[0004] In order to achieve the above object, the technical solution of the present invention is:

[0005] A nanosecond laser processing method for a super-hydrophobic surface of an ultra-fine metal wire comprises the following steps:

[0006] S1: cutting the ultrafine metal wire into the required length, grinding the surface of the ultrafine metal wire with sandpaper, ultrasonically cleaning the ultrafine metal wire with deionized water, and drying the ultrafine metal wire to complete the pretreatment;

[0007] S2: Clamp the pre-treated ultra-fine metal wire onto the fixture;

[0008] S3: A nanosecond laser with a wavelength of 1064nm, a repetition frequency of 20kHz, a pulse duration of 100ns, and a spot diameter of about 50μm is used to etch the ultrafine metal wire to construct a microstructure. The parameters of the nanosecond laser processing are power of 3W to 15W, scanning speed of 300mm / s to 700mm / s, and scanning times of 1 to 5 times; the ultrafine metal wire is driven to rotate by a rotating fixture to achieve partitioned processing of the surface of the ultrafine metal wire, and each time the processing of one area is completed, the fixture drives the metal wire to rotate once until the single laser processing of all areas is completed;

[0009] S4: Soaking the laser processed ultrafine metal wire in a fluorosilane ethanol solution and then drying it to complete the super-hydrophobic surface nanosecond laser processing of the ultrafine metal wire surface.

[0010] Furthermore, the mass fraction of the fluorosilane ethanol solution is 1wt%.

[0011] Furthermore, the drying condition is: baking at 80° C. for 20 minutes.

[0012] Furthermore, the material of the ultrafine metal wire is copper, aluminum, iron, titanium and alloys thereof.

[0013] Furthermore, the ultrafine metal wire is a metal wire with a diameter not exceeding 500 μm.

[0014] A fixture used in the nanosecond laser processing method for the super-hydrophobic surface of an ultra-fine metal wire comprises a first fixture and a second fixture of the same structure, wherein the first fixture and the second fixture are arranged front and back to clamp the front and back ends of the ultra-fine metal wire respectively;

[0015] The first clamp and the second clamp both comprise a base, a dividing wheel disc and a nut, the base is provided with a dividing wheel disc mounting groove, a through hole is provided in the dividing wheel disc mounting groove, and a positioning protrusion is provided on the dividing wheel disc mounting groove;

[0016] The indexing wheel is in the shape of a disc, a metal wire clamping hole is arranged in the center of the indexing wheel, four slots are evenly distributed around the disc surface of one side of the indexing wheel, and a threaded hole is arranged on the disc surface of the other side of the indexing wheel. When processing ultra-fine metal wires, the indexing wheel is installed in the indexing wheel installation slot, and the positioning protrusion is arranged in one of the slots, and the two ends of the ultra-fine metal wire pass through the through holes and are clamped in the metal wire clamping hole respectively, and the end of the ultra-fine metal wire extending out of the metal wire installed in the clamping hole is pressed by the nut installed in the threaded hole;

[0017] After processing one quarter of the surface of the ultrafine metal wire, the dividing wheel 1 is rotated 90 degrees around the axis to drive the ultrafine metal wire to rotate 90 degrees around its axis to process the next quarter of the surface of the ultrafine metal wire.

[0018] The beneficial effects of the present invention are:

[0019] The present invention discloses a nanosecond laser processing method for super-hydrophobic surface of ultra-fine metal wire, which has simple process, no need to use expensive chemical reagents, low cost, and can process super-hydrophobic surface on ultra-fine wires of metals such as copper, aluminum, iron, titanium and their alloys, so the material has good versatility; no toxic chemical gas is generated and discharged, so the environmental pollution is small; the processing efficiency is high, and the microstructure required for super-hydrophobicity can be constructed on the surface of the ultra-fine metal wire in just a few minutes. At the same time, the surface of the ultra-fine metal wire is processed in different areas, which effectively avoids repeated processing of the same area, ensures the processing uniformity of the surface of the ultra-fine metal wire, and improves the processing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 is a schematic diagram of the fixture;

[0022] Figure 2 is a schematic diagram of the base structure;

[0023] Figure 3 It is a dividing wheel. Figure 1 ;

[0024] Figure 4 It is a dividing wheel. Figure 2 ;

[0025] Figure 5 This is an electron microscope image of the super-hydrophobic surface of the ultra-fine brass wire obtained under the processing conditions of 6W power, 500mm / s scanning speed and 1 scanning number in Example 1;

[0026] Figure 6 This is a contact angle diagram of a 5 μL water drop on the super-hydrophobic surface of an ultra-fine brass wire obtained under the processing conditions of 6 W power, 500 mm / s scanning speed, and 1 scanning number in Example 1.

[0027] In the figure:

[0028] 1. Base; 11. Indexing wheel installation slot; 12. Limiting protrusion; 13. Through hole;

[0029] 2. Indexing wheel; 21. Slot; 22. Threaded hole; 23. Wire clamping hole;

[0030] 3. Nut;

[0031] 4. Gasket;

[0032] 5. Ultra-fine metal wire. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The principles involved in this application are:

[0035] First, cut the metal wire to a certain length, and then polish, ultrasonically clean and dry the metal wire with deionized water to completely remove other impurities on the surface of the metal wire to avoid affecting the results of subsequent laser processing. Then, clamp the pretreated metal wire on the fixture to keep the metal wire taut to ensure that the surface of the metal wire can evenly absorb the laser energy during laser processing. The angle of each rotation of the metal wire is accurately controlled by the dividing wheel to be 90° (3 rotations in total) to ensure that the surface of the metal wire can evenly form a micro / nano composite structure under the action of the laser. Finally, the laser-processed metal wire is immersed in a 1wt% fluorosilane ethanol solution to graft the silane groups in the fluorosilane molecules to the surface of the metal wire, reduce the surface energy of the material, and bake at high temperature (80°C) to promote the fluorosilane molecules to bind more firmly to the surface, so that it has long-lasting super-hydrophobic properties.

[0036] Example

[0037] Embodiment 1:

[0038] S1: Pretreatment: The brass wire with a diameter of 200 μm was cut into 12 cm pieces, and then polished with 1200# and 2000# sandpapers respectively, and then ultrasonically cleaned with deionized water for 2 min, and dried to complete the pretreatment process;

[0039] The fixture structure used in this method is as follows Figure 1-4 As shown, it comprises a first clamp and a second clamp of the same structure, wherein the first clamp and the second clamp are arranged front and rear respectively for clamping the front and rear ends of the ultra-fine metal wire;

[0040] The first clamp and the second clamp both include a base 1, a dividing wheel 2 and a nut 3, the base is provided with a dividing wheel installation groove 11, the dividing wheel installation groove is provided with a through hole 13, and the dividing wheel installation groove is provided with a positioning protrusion 12;

[0041] The indexing wheel 1 is in the shape of a disk, and a metal wire clamping hole 23 is provided in the center of the indexing wheel 1. Four slots 21 are evenly distributed around the disk surface of one side of the indexing wheel 2, and a threaded hole 22 is provided on the disk surface of the other side of the indexing wheel 2. When processing the ultra-fine metal wire 5, the indexing wheel 2 is installed in the indexing wheel installation slot 11, and the positioning protrusion 12 is arranged in one of the slots 21. The two ends of the ultra-fine metal wire 5 pass through the through hole 13 respectively and are clamped in the metal wire clamping hole 23, and the end of the ultra-fine metal wire extending out of the metal wire installed in the clamping hole 23 is pressed by the nut 3 installed in the threaded hole.

[0042] S2: Clamping process: the brass wire is passed through the through hole of the base and the wire clamping hole of the indexing wheel, the wire is tightened, and the end of the wire extending out of the wire clamping hole is clamped and fixed by a nut installed in the threaded hole and a gasket arranged between the wire and the nut;

[0043] S3: After the ultrafine metal wire is fixed, laser processing is performed, specifically: a nanosecond laser with a wavelength of 1064nm, a repetition frequency of 20kHz, a pulse duration of 100ns, and a spot diameter of about 50μm is used to etch the brass wire to construct a microstructure; the nanosecond laser processing parameters are power 6W, scanning speed 500mm / s, and scanning times 1 time. After completing the processing of 1 / 4 area of ​​the surface of the ultrafine metal wire, the nut is loosened, and the dividing wheel is removed from the dividing wheel installation groove in the axial direction, and then the dividing wheel 1 is rotated 90° around the axis once, driving the ultrafine metal wire 5 to rotate 90° around its axis, and the next 1 / 4 area of ​​the ultrafine metal wire surface is processed. The microscopic morphology of the brass wire surface after laser processing is as follows Figure 5 As shown;

[0044] S4: Low surface energy treatment: The laser processed brass wire was immersed in a 1wt% fluorosilane ethanol solution and then baked at 80°C for 20 minutes. The contact angle of a water drop on the superhydrophobic brass wire is shown in Figure 2. Figure 6 As shown. With a laser power of 6W, a scanning speed of 500mm / s, and a scanning number of 1, a spike-like microstructure can be processed on the brass surface. According to the Cassie-Baxter model, its theoretical superhydrophobic performance should be greatly improved. The experimental measurement is consistent with the theory, and its contact angle can reach 156°, which has excellent superhydrophobic performance.

[0045] Embodiment 2:

[0046] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 3W, scanning speed 500mm / s, scanning number 1. The ultra-fine metal wire after processing is tested and measured, and its contact angle is 144°.

[0047] Embodiment 3:

[0048] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 9W, scanning speed 500mm / s, scanning number 1. The ultra-fine metal wire after processing is tested and measured, and its contact angle is 150°.

[0049] Embodiment 4:

[0050] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 12W, scanning speed 500mm / s, scanning number 1. The ultra-fine metal wire after processing is tested and measured, and its contact angle is 147°.

[0051] Embodiment 5:

[0052] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 15W, scanning speed 500mm / s, scanning number 1. The ultra-fine metal wire after processing is tested and measured, and its contact angle is 148°.

[0053] Embodiment 6:

[0054] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 6W, scanning speed 300mm / s, scanning number 1. The ultra-fine metal wire after processing is tested and measured, and its contact angle is 154°.

[0055] Embodiment 7:

[0056] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 6W, scanning speed 400mm / s, scanning number 1. The ultra-fine metal wire after processing is tested and measured, and its contact angle is 153°.

[0057] Embodiment 8:

[0058] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 6W, scanning speed 600mm / s, scanning number 1. The ultra-fine metal wire after processing is tested and measured, and its contact angle is 148°.

[0059] Embodiment 9:

[0060] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 6W, scanning speed 700mm / s, scanning number 1. The ultra-fine metal wire after processing is tested and measured, and its contact angle is 140°.

[0061] Embodiment 10:

[0062] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 6W, scanning speed 500mm / s, scanning times 2 times. The ultra-fine metal wire after the processing is tested and measured, and its contact angle is 156°.

[0063] Embodiment 11:

[0064] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 6W, scanning speed 500mm / s, scanning times 3 times. The ultra-fine metal wire after the processing is tested and measured, and its contact angle is 153°.

[0065] Embodiment 12:

[0066] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 6W, scanning speed 500mm / s, scanning times 4 times. The ultra-fine metal wire after the processing is tested and measured, and its contact angle is 138°.

[0067] Embodiment 13:

[0068] The difference between this embodiment and embodiment 1 is that in this embodiment, the nanosecond laser processing parameters are: power 6W, scanning speed 500mm / s, scanning times 5 times. The ultra-fine metal wire after processing is tested and measured, and its contact angle is 148°.

[0069] Comparative Example

[0070] Comparative Example 1:

[0071] The only difference between this comparative example and Example 1 is that in this comparative example, the nanosecond laser processing parameters are: power 1.5 W, scanning speed 500 mm / s, scanning number 1. The ultra-fine metal wire after the processing was tested and measured, and its contact angle was 142°.

[0072] Comparative Example 2:

[0073] The only difference between this comparative example and Example 1 is that in this comparative example, the nanosecond laser processing parameters are: power 16.5 W, scanning speed 500 mm / s, scanning number 1. The ultra-fine metal wire after the processing was tested and measured, and its contact angle was 149°.

[0074] Comparative Example 3:

[0075] The difference between this comparative example and Example 1 is that in this comparative example, the nanosecond laser processing parameters are: power 6W, scanning speed 200mm / s, scanning number 1. The ultra-fine metal wire after the processing is tested and measured, and its contact angle is 151°.

[0076] Comparative Example 4:

[0077] The only difference between this comparative example and Example 1 is that in this comparative example, the nanosecond laser processing parameters are: power 6W, scanning speed 800mm / s, scanning number 1. The ultra-fine metal wire after the processing was tested and measured, and its contact angle was 140°.

[0078] Comparative Example 5:

[0079] The only difference between this comparative example and Example 1 is that in this comparative example, the nanosecond laser processing parameters are: power 6W, scanning speed 500mm / s, scanning times 6 times. The ultra-fine metal wire after the processing is tested and measured, and its contact angle is 140°.

[0080] The processing parameters and results of Examples 1-13 and Comparative Examples 1-5 are shown in the following table:

[0081]

[0082]

[0083] It can be seen from the data in the above table that only within the range of processing parameters provided by the present invention can the processing of the super-hydrophobic structure on the surface of the ultrafine metal wire be achieved, that is, within the range of power 3W to 15W, scanning speed 300mm / s to 700mm / s, and scanning times 1 to 5 times, a better processing effect can be achieved, wherein, there is no difference between processing twice and processing once, combined with consideration of processing cost, therefore, the optimal processing parameters are power 6W, scanning speed 500mm / s, and scanning times 1 in Example 1.

[0084] In summary, the present invention realizes the zoned processing of the super-hydrophobic structure on the surface of the ultra-fine metal wire by setting a clamp, thereby improving the processing uniformity of the ultra-fine metal wire, and combined with the processing technology parameters set in this application, finally realizes the processing of the super-hydrophobic structure on the surface of the ultra-fine metal wire and ensures the processing quality. The method has simple steps, low cost, good material versatility, does not produce toxic substances and gases, and has little environmental pollution.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A nanosecond laser processing method for super-hydrophobic surface of ultra-fine metal wire, characterized in that: The steps include: S1: cutting the ultra-fine metal wire into the required length, grinding the surface of the ultra-fine metal wire with sandpaper, ultrasonically cleaning the ultra-fine metal wire with deionized water, and drying the ultra-fine metal wire to complete the pretreatment; S2: Clamp the pre-treated ultra-fine metal wire onto the fixture; S3: A nanosecond laser with a wavelength of 1064nm, a repetition frequency of 20kHz, a pulse duration of 100ns, and a spot diameter of about 50μm is used to etch the ultrafine metal wire to construct a microstructure. The parameters of the nanosecond laser processing are power of 3W to 15W, scanning speed of 300mm / s to 700mm / s, and scanning times of 1 to 5 times; the ultrafine metal wire is driven to rotate by a rotating fixture to achieve partitioned processing of the surface of the ultrafine metal wire, and each time the processing of one area is completed, the fixture drives the metal wire to rotate once until the single laser processing of all areas is completed; S4: Soaking the laser processed ultrafine metal wire in a fluorosilane ethanol solution and then drying it to complete the super-hydrophobic surface nanosecond laser processing of the ultrafine metal wire surface.

2. The nanosecond laser processing method for super-hydrophobic surface of ultra-fine metal wire according to claim 1, characterized in that: The mass fraction of the fluorosilane ethanol solution is 1 wt %.

3. The nanosecond laser processing method for super-hydrophobic surface of ultra-fine metal wire according to claim 1, characterized in that: The drying condition is: drying at 80° C. for 20 min.

4. The nanosecond laser processing method for super-hydrophobic surface of ultra-fine metal wire according to claim 1, characterized in that: The material of the superfine metal wire is copper, aluminum, iron, titanium metal and alloys thereof.

5. The nanosecond laser processing method for super-hydrophobic surface of ultra-fine metal wire according to claim 4, characterized in that: The ultrafine metal wire is a metal wire with a diameter not exceeding 500 μm.

6. A fixture used in the nanosecond laser processing method for super-hydrophobic surface of ultra-fine metal wire according to claim 1, characterized in that: It comprises a first clamp and a second clamp of the same structure, wherein the first clamp and the second clamp are arranged front and back to clamp the front and back ends of the ultra-fine metal wire respectively; The first clamp and the second clamp both comprise a base (1), a dividing wheel disc (2) and a nut (3); the base is provided with a dividing wheel disc mounting groove (11); a through hole (13) is provided in the dividing wheel disc mounting groove (11); and a positioning protrusion (12) is provided on the dividing wheel disc mounting groove; The dividing wheel (1) is in the shape of a circular disc, and a metal wire clamping hole (23) is provided at the center of the dividing wheel (1). Four clamping grooves (21) are evenly distributed around the disc surface of one side of the dividing wheel (2), and a threaded hole (22) is provided on the disc surface of the other side of the dividing wheel (2). When processing the ultra-fine metal wire (5), the dividing wheel (2) is installed in the dividing wheel installation groove (11), and the positioning protrusion (12) is arranged in one of the clamping grooves (21). The two ends of the ultra-fine metal wire (5) respectively pass through the through hole (13) and are clamped in the metal wire clamping hole (23), and the end of the ultra-fine metal wire extending out of the metal wire installed in the clamping hole (23) is pressed by the nut (3) installed in the threaded hole. After processing one quarter of the surface of the ultra-fine metal wire, the dividing wheel (1) is rotated once by 90 degrees around the axis, driving the ultra-fine metal wire (5) to rotate 90 degrees around its axis, thereby processing the next quarter of the surface of the ultra-fine metal wire.

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