阅读说明：本技术 一种基于激光微织构的非晶合金功能化表面制备方法 (Laser micro-texture based amorphous alloy functionalized surface preparation method ) 是由 程杨洋 王青华 王慧鑫 于 2021-10-27 设计创作，主要内容包括：本发明公开了一种基于激光微织构的非晶合金功能化表面制备方法,所述制备步骤主要包括：1)清洗基底：对非晶合金基底进行清洗；2)激光表面微织构：利用紫外纳秒激光束在非晶合金基底表面加工微纳结构；3)低温热处理：将步骤2)处理后的非晶合金基底在真空干燥箱中进行低温热处理；本发明通过紫外激光加工与低温热处理共同作用,制备的非晶合金表面展现出了表面微纳结构与表面化学的改变,从而实现了超亲水向超疏水特性的转变,激光微织构非晶合金表面的显微硬度也得到了显著提升。(The invention discloses a method for preparing an amorphous alloy functionalized surface based on laser microtexture, which mainly comprises the following steps: 1) cleaning a substrate: cleaning the amorphous alloy substrate; 2) laser surface microtexturing: processing a micro-nano structure on the surface of the amorphous alloy substrate by using an ultraviolet nanosecond laser beam; 3) low-temperature heat treatment: carrying out low-temperature heat treatment on the amorphous alloy substrate treated in the step 2) in a vacuum drying oven; according to the invention, through the combined action of ultraviolet laser processing and low-temperature heat treatment, the surface of the prepared amorphous alloy shows the change of a surface micro-nano structure and surface chemistry, so that the conversion from super-hydrophilicity to super-hydrophobicity is realized, and the microhardness of the surface of the laser micro-texture amorphous alloy is also obviously improved.)

1. A preparation method of an amorphous alloy functionalized surface based on laser microtexture is characterized by comprising the following steps:

step 1) cleaning a substrate: cleaning the amorphous alloy substrate;

step 2) laser surface microtexturing: placing the cleaned amorphous alloy substrate on a sample table of an ultraviolet nanosecond laser processing system, wherein parameters of an ultraviolet nanosecond pulse laser in the system are as follows: the pulse width is 20ns, the wavelength of the laser is 200-400 nm, the pulse repetition frequency is 10-30 kHz, the laser power is 1-15W, the pulse energy is 0.1-0.5 mJ, and the laser power density is 1.0-4.0 GW/cm²The focused effective light spot diameter is about 25-30 microns, the laser scanning speed is 20-80 mm/s, the laser beam scanning area is 12mm multiplied by 12mm, a micro-nano structure is processed on the surface of the amorphous alloy substrate by using the laser beam, and then the ultrasonic cleaning is carried out in absolute ethyl alcohol for 10-15 minutes;

step 3) low-temperature heat treatment: carrying out heat treatment on the amorphous alloy substrate treated in the step 2) in a vacuum drying oven for 1-2 hours at the drying temperature of 150-200 ℃, then taking out and cleaning with deionized water, and finally drying in nitrogen flow.

2. The method for preparing the functionalized surface of the amorphous alloy based on the laser microtexture as claimed in claim 1, wherein the alloy substrate is a zirconium-based bulk amorphous alloy, Zr₆₅Al_7.5Ni₁₀Cu_17.5Or Zr_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5。

3. The method for preparing the amorphous alloy functionalized surface based on the laser microtexture as claimed in claim 1, wherein the cleaning process in the step 1) is as follows: and (3) placing the amorphous alloy substrate in acetone, absolute ethyl alcohol and deionized water in sequence, ultrasonically cleaning for 10-15 minutes, and then placing the substrate in nitrogen flow for drying.

4. The method for preparing the laser microtexture-based amorphous alloy functionalized surface according to claim 1, wherein the laser wavelength in the step 2) is 355 nm.

5. The method for preparing the amorphous alloy functionalized surface based on the laser microtexture, according to claim 1, characterized in that the surface structure of the micro-nano structure in the step 2) is a micron-sized square column array or a concave groove in a unidirectional, annular or crossed shape.

6. The method for preparing the amorphous alloy functionalized surface based on the laser microtexture, according to claim 5, is characterized in that the micro-nano structure array structure has a square column and groove spacing of 100-300 μm, a square column height of 20-30 μm and a groove depth of 30-50 μm.

7. The method for preparing the laser microtexture-based amorphous alloy functionalized surface according to claim 5, wherein the micro-nano structure surface is covered with submicron or nano-scale sputtering particles.

8. The method for preparing the amorphous alloy functionalized surface based on the laser microtexture as claimed in claim 1, wherein the vacuum drying oven in the step 3) is not vacuumized, and is set to be 5m³Exhaust gas flow rate/h.

9. The method for preparing the laser microtexture-based amorphous alloy functionalized surface according to claim 1, wherein the heat treatment time in the step 3) is 2 hours, and the drying temperature is 150 ℃.

10. The application of the amorphous alloy functionalized surface obtained by the preparation method according to any one of claims 1 to 9 in biomedicine, aerospace materials, electronic products and acoustic materials.

Technical Field

The invention belongs to the field of material processing engineering, and particularly relates to a preparation method of an amorphous alloy functionalized surface based on laser microtexture.

Technical Field

Amorphous alloys, also known as metallic glass, have a special microstructure of short-range order and long-range disorder, exhibit incomparable physical and mechanical properties of common crystalline metals, such as high strength, high hardness, low Young's modulus, excellent corrosion/abrasion resistance and excellent magnetism, and have great potential application prospects in various fields of machinery, materials, microelectronics, medical instruments and the like. Therefore, in the last decade, the forming and processing technology of amorphous alloy has become the popular research direction of related researchers, and many technologies including copper mold casting, thermoplastic forming, magnetron sputtering, arc oxidation and the like have been widely applied to the process of forming amorphous alloy. However, with the development of complex amorphous alloy structural parts, the traditional manufacturing process is difficult to meet the requirements, the forming efficiency of the copper mold casting method is high, and the forming size of the amorphous alloy structural part is limited to a certain extent; the thermoplastic forming method has high forming precision, but the forming size is still limited, the requirements on powder components are strict, and the turning and electric spark machining technology in the machining aspect is very easy to cause crystallization of amorphous materials in the machining process.

Therefore, it is highly desirable to search for efficient processing and forming techniques for amorphous alloys. Laser material processing has gained wide attention in recent years as an advanced processing technology with the advantages of high precision, high process flexibility, high automation degree, low environmental pollution and the like. The pulse laser is used for processing the amorphous alloy, so that the heating and cooling periods can be controlled in a small range, and crystallization is avoided to the greatest extent while the material performance is improved. Some of the results in recent years have been published in the field: huang et al prepared a multi-level micro-nano structure on a bulk amorphous alloy based on zirconium by using nanosecond pulsed laser, the laser modified amorphous alloy successfully increased the effective surface area, and the surface chemical elements were very uniformly distributed while maintaining the amorphous state (Huang H, Jun N, Jiang M, Ryoko M, Yan J, Materials and Design,2016,109: 153-. Jiao et al prepared periodic Surface structures, including pit and trench structures, on bulk zirconium based amorphous alloys using nanosecond laser microtexturing methods, and the test results showed that the wettability and biocompatibility of amorphous alloys are closely related to the Surface roughness and Surface chemistry after laser action, indicating that the laser microtexturing process has a large impact on the Surface properties of amorphous alloys (Jiao Y, Brousseau E, Han Q, Zhu H, Bigot S., Journal of Materials Processing Technology,2019,273: 116232; Jiao Y, Brousseau E, Shen X, Wang X, Han Q, Zhu H, Bigot S, He W, Journal of Materials Processing Technology,2020,283: 116714; Jiao Y, Brousseau E, nisio Ayre W, gaiit-Carr E, Shen X, Wang X, bit S, Zhu H, Applied H, He 2021,547, He 82). Du et al prepared a Laser Induced Periodic Surface Structure (LIPSS) on four different zirconium-based bulk amorphous alloys by using femtosecond laser, and the experimental results showed that the laser prepared surface structure can effectively reduce the adhesion rate of bacteria on the surface, thereby improving the antibacterial performance (Du C, Wang C, Zhang T, Yi X, Liang J, Wang H., Proceedings of the institute of Mechanical Engineers, Part H: Journal of Engineering in Medicine,2020,234 (387) and 397.). Yao Yansheng et al use femtosecond laser to prepare a linear structure on a zirconium-based bulk amorphous alloy, and found that after laser treatment, the hydrophilicity and corrosion resistance of the amorphous alloy are significantly improved, and thus the applicability of the amorphous alloy as an implant in the human body is significantly enhanced (Yao Yansheng, Tangjianpin, Zhang Yao super, Hoffodia, Wudong, Chinese laser, 2021,48(2): 0202012). Chinese patent CN113278903A discloses a method for enhancing the surface hardness of a zirconium-based amorphous alloy by laser irradiation of silicon carbide particles, which mainly improves the surface hardness of the zirconium-based amorphous alloy by adding a silicon carbide particle medium under the irradiation of near-infrared (1064nm) nanosecond pulse laser. The surface of the zirconium-based amorphous alloy prepared by the method has higher hardness, but a large amount of silicon carbide medium needs to be introduced, and the cost is overhigh. Chinese patent CN112553569B discloses a method for improving surface hardness of a zirconium-based amorphous alloy through nanosecond laser carbonization, which mainly utilizes the characteristic that a carbon element and a zirconium element react to generate a zirconium carbide phase at a high temperature, and introduces the zirconium carbide phase on the surface of the zirconium-based amorphous alloy to greatly improve the surface hardness of the zirconium-based amorphous alloy, but the method utilizes nanosecond pulse laser irradiation of near infrared (1064nm) with the pulse frequency as high as 600-800 kHz, and obtains the zirconium carbide phase through additional graphite powder at the high temperature, so that the cost is greatly increased, and super-hydrophobicity is not realized. Therefore, according to the existing research work, laser processing has become an important method and means for processing and manufacturing amorphous alloys, and particularly shows good development and application prospects in the field of surface modification and functionalization.

Indeed, laser processing has proven to be an efficient means in the field of amorphous alloy processing and manufacturing, but some problems still remain to be solved, and although researchers have implemented changes in surface properties of amorphous alloys using laser microtexture methods, there is no way to regulate and control the relevant properties, such as how to implement the conversion between hydrophilic and hydrophobic properties, and secondly, the existing laser methods have low preparation efficiency, and at the same time, the obtained surface reliability and durability still need to be improved.

Disclosure of Invention

In order to solve the prior technical problems, the invention provides a preparation method of an amorphous alloy functionalized surface based on laser microtexture, which realizes the regulation and control of surface functions such as wettability, hardness and the like;

the preparation method of the amorphous alloy functionalized surface based on the laser microtexture comprises the following specific steps:

step 1) cleaning a substrate: cleaning the amorphous alloy substrate;

step 2) laser surface microtexturing: placing the cleaned amorphous alloy substrate on a sample table of an ultraviolet nanosecond laser processing system, wherein parameters of an ultraviolet nanosecond pulse laser in the system are as follows: the pulse width is 20ns, the wavelength of the laser is 200-400 nm, the pulse repetition frequency is 10-30 kHz, the laser power is 1-15W, the pulse energy is 0.1-0.5 mJ, and the laser power density is 1.0-4.0 GW/cm²The focused effective light spot diameter is about 25-30 microns, the laser scanning speed is 20-80 mm/s, the laser beam scanning area is 12mm multiplied by 12mm, a micro-nano structure is processed on the surface of the amorphous alloy substrate by using the laser beam, and then the ultrasonic cleaning is carried out in absolute ethyl alcohol for 10-15 minutes;

step 3) low-temperature heat treatment: carrying out heat treatment on the amorphous alloy substrate treated in the step 2) in a vacuum drying oven for 1-2 hours at the drying temperature of 150-200 ℃, then taking out and cleaning with deionized water, and finally drying in nitrogen flow.

The alloy substrate is a zirconium-based bulk amorphous alloy, Zr₆₅Al_7.5Ni₁₀Cu_17.5Or Zr_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5。

The cleaning process in the step 1) is as follows: and (3) placing the amorphous alloy substrate in acetone, absolute ethyl alcohol and deionized water in sequence, ultrasonically cleaning for 10-15 minutes, and then placing the substrate in nitrogen flow for drying.

Preferably, the laser wavelength in the step 2) is 355 nm.

The surface structure of the micro-nano structure in the step 2) is a unidirectional, annular or crossed micron-scale square column array or a concave groove.

The micro-nano structure array structure is characterized in that the distance between a square column and a groove is 100-300 mu m, the height of the square column is 20-30 mu m, and the depth of the groove is 30-50 mu m.

The surface of the micro-nano structure is covered with submicron or nano-scale sputtering particles.

The vacuum drying oven in the step 3) is not vacuumized and is set to be 5m³Exhaust gas flow rate/h.

Preferably, the heat treatment time in the step 3) is 2 hours, and the drying temperature is 150 ℃.

Compared with the prior art, the invention has the following beneficial effects:

(1) according to the invention, in the process of preparing the amorphous alloy, the structural form of the surface of the amorphous alloy can be effectively controlled by controlling laser parameters, and the free conversion between the micro-convex structure and the micro-concave structure on the surface of the amorphous alloy can be realized by reasonably controlling the laser energy density and the laser pulse frequency and number and changing the laser scanning rate regulation;

(2) the invention adopts the ultraviolet nanosecond pulse laser with the wavelength of 355nm, compared with the near infrared nanosecond laser with the wavelength of 1064nm, the invention not only ensures the precise control of the micro-concave structure of the micro-protrusion on the surface of the amorphous alloy, but also can reduce the heat effect in the laser processing process, reduce the heat affected zone and prepare the high-quality surface micro-nano structure, thereby laying a foundation for the surface functionalization of the amorphous alloy;

(3) the surface of the amorphous alloy prepared by the invention contains nonpolar hydrophobic groups (such as-CH)₂-,-CH₃C ═ C and other functional groups) on the surface of the amorphous alloy, and simultaneously, the deposition process of the silicon-containing film is induced by adopting low-temperature heat treatment, and due to the deposition of the nonpolar hydrophobic group and the silicon-containing film on the surface, the conversion from the super-hydrophilic characteristic to the super-hydrophobic characteristic can be realized on the surface of the laser micro-texture amorphous alloy, and the amorphous alloy surface shows better hydrophobic characteristic and even super-hydrophobic characteristic under the combined action of the nonpolar hydrophobic group and the silicon-containing film;

(4) the amorphous alloy prepared by the laser surface microtexture process has a unidirectional groove structure, the microhardness of the microtexture surface reaches 570.8 +/-4.9 HV, and is improved by 10.6% compared with that of an untreated surface, wherein the microhardness of the untreated surface is 516.2 +/-4.6 HV;

(5) according to the invention, the surface of the amorphous alloy is processed by the laser microtexture to prepare the periodic micro-nano structure, so that more refined grains are generated on the surface, and more grain boundaries are generated during grain refinement, so that the resistance of dislocation movement of the material is enhanced, and the hardness of the surface of the amorphous alloy can be improved;

(6) the amorphous alloy containing the micro-nano structure prepared by the invention can be used in the fields of biomedicine, aerospace materials, electronic products, acoustic materials and the like.

Drawings

FIG. 1 is a graph showing the effect of heat treatment time on surface wettability during the preparation of an amorphous alloy.

FIG. 2 is the microhardness of the laser microtextured amorphous alloy surface and the untreated amorphous alloy surface prepared in example 3.

FIG. 3 is the scanning electron microscope images of the shapes of the untreated amorphous alloy surface (a) and the laser microtextured amorphous alloy surfaces (b-e) using different scanning speeds in example 3.

Fig. 4 shows XPS spectroscopy analysis of the amorphous alloy surface prepared in example 3, wherein (a), (b), and (c) respectively represent the untreated alloy surface, the laser microtextured amorphous alloy surface, and the heat-treated laser microtextured amorphous alloy surface.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the description is intended to be exemplary only, and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

The terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, article, or device that comprises a list of steps is not limited to only those steps or modules listed, but may alternatively include other steps not listed or inherent to such process, method, article, or device.

The invention is further described in the following examples, which are not intended to limit the scope of the invention.

Example 1

Step 1): zr based bulk amorphous alloy_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5Cutting into 30mm multiplied by 30mm, then sequentially ultrasonically cleaning for 10 minutes by acetone, absolute ethyl alcohol and deionized water respectively to remove pollutants on the surface of the substrate, and then blowing in nitrogen flow for drying;

step 2): carrying out laser microtexture on the surface of the substrate treated in the step 1) by adopting an ultraviolet nanosecond pulse laser, wherein the selected laser parameters are as follows: the pulse width is 20ns, the laser wavelength is 355nm, the pulse repetition frequency is 10kHz, the laser power is 1W, the pulse energy is 0.1mJ, and the laser power density is 1.0GW/cm²The effective spot diameter after focusing is about 25 μm, the laser scanning speed is 20mm/s, and the laser beam scanning area is12mm multiplied by 12mm, and the laser preparation substrate is put into absolute ethyl alcohol for ultrasonic cleaning for 12 minutes;

step 3): and (3) putting the substrate obtained in the step 2) into a vacuum drying oven for low-temperature heat treatment, wherein the drying oven is not vacuumized in the treatment process, the air is kept smooth, and the substrate is subjected to heat treatment for 1.0 hour at the temperature of 150 ℃.

Example 2

Step 1): zr based bulk amorphous alloy_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5Cutting into 30mm multiplied by 30mm, then sequentially ultrasonically cleaning for 10 minutes by acetone, absolute ethyl alcohol and deionized water respectively to remove pollutants on the surface of the substrate, and then blowing in nitrogen flow for drying;

step 2): carrying out laser microtexture on the surface of the substrate treated in the step 1) by adopting an ultraviolet nanosecond pulse laser, wherein the selected laser parameters are as follows: the pulse width is 20ns, the laser wavelength is 355nm, the pulse repetition frequency is 10kHz, the laser power is 1W, the pulse energy is 0.1mJ, and the laser power density is 1.0GW/cm²The diameter of the focused effective light spot is about 25 mu m, the laser scanning speed is 20mm/s, the laser beam scanning area is 12mm multiplied by 12mm, and the laser preparation substrate is placed into absolute ethyl alcohol for ultrasonic cleaning for 12 minutes;

step 3): and (3) putting the substrate obtained in the step 2) into a vacuum drying oven for low-temperature heat treatment, wherein the drying oven is not vacuumized in the treatment process, the air is kept smooth, and the substrate is subjected to heat treatment for 1.5 hours at the temperature of 150 ℃.

Example 3

Step 1): zr based bulk amorphous alloy_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5Cutting into 30mm multiplied by 30mm, then sequentially ultrasonically cleaning for 10 minutes by acetone, absolute ethyl alcohol and deionized water respectively to remove pollutants on the surface of the substrate, and then blowing in nitrogen flow for drying;

step 2): carrying out laser microtexture on the surface of the substrate treated in the step 1) by adopting an ultraviolet nanosecond pulse laser, wherein the selected laser parameters are as follows: pulse width of 20ns, laser wavelength of 355nm, pulse repetition frequency of 10kHz, laser power of 1W, pulse width ofThe impact energy is 0.1mJ, and the laser power density is 1.0GW/cm²The diameter of the focused effective light spot is about 25 mu m, the laser scanning speed is 20mm/s, the laser beam scanning area is 12mm multiplied by 12mm, and the laser preparation substrate is placed into absolute ethyl alcohol for ultrasonic cleaning for 12 minutes;

step 3): and (3) putting the substrate obtained in the step 2) into a vacuum drying oven for low-temperature heat treatment, wherein the drying oven is not vacuumized in the treatment process, the air is kept smooth, and the substrate is subjected to heat treatment for 2.0 hours at the temperature of 150 ℃.

Example 4

Step 1): zr based bulk amorphous alloy_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5The substrate is cut into a size of 20mm multiplied by 20mm, then is sequentially and respectively ultrasonically cleaned for 12 minutes by acetone, absolute ethyl alcohol and deionized water so as to remove pollutants on the surface of the substrate, and then is placed in a nitrogen flow for drying.

Step 2): carrying out laser microtexture on the surface of the substrate treated in the step 1) by adopting an ultraviolet nanosecond pulse laser, wherein the selected laser parameters are as follows: the pulse width is 20ns, the laser wavelength is 355nm, the pulse repetition frequency is 30kHz, the laser power is 15W, the pulse energy is 0.5mJ, and the laser power density is 4.0GW/cm²The diameter of the focused effective light spot is about 28 μm, the laser scanning speed is 80mm/s, the laser beam scanning area is 15mm multiplied by 15mm, and the laser preparation substrate is placed in absolute ethyl alcohol for ultrasonic cleaning for 15 minutes.

Step 3): and (3) putting the substrate obtained in the step 2) into a vacuum drying oven for low-temperature heat treatment, wherein the drying oven is not vacuumized in the treatment process, the air is kept smooth, and the substrate is subjected to heat treatment for 2.0 hours at the temperature of 200 ℃.

Comparative example 1

Step 1): zr based bulk amorphous alloy_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5Cutting into 30mm multiplied by 30mm, then sequentially ultrasonically cleaning for 10 minutes by acetone, absolute ethyl alcohol and deionized water respectively to remove pollutants on the surface of the substrate, and then blowing in nitrogen flow for drying;

step 2): adopting a near-infrared pulse laser to treat the substrate surface treated in the step 1)Carrying out laser microtexture on the surface, wherein the selected laser parameters are as follows: the pulse width is 20ns, the laser wavelength is 1064nm, the pulse repetition frequency is 20kHz, the laser power is 1W, the pulse energy is 0.05mJ, and the laser power density is 0.35GW/cm²The diameter of the focused effective light spot is about 30 mu m, the laser scanning speed is 20mm/s, the laser beam scanning area is 12mm multiplied by 12mm, and the laser preparation substrate is placed into absolute ethyl alcohol for ultrasonic cleaning for 12 minutes;

step 3): and (3) putting the substrate obtained in the step 2) into a vacuum drying oven for low-temperature heat treatment, wherein the drying oven is not vacuumized in the treatment process, the air is kept smooth, and the substrate is subjected to heat treatment for 2.0 hours at the temperature of 150 ℃.

Comparative example 2

Step 1): zr based bulk amorphous alloy_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5The substrate is cut into a size of 20mm multiplied by 20mm, then is sequentially and respectively ultrasonically cleaned for 12 minutes by acetone, absolute ethyl alcohol and deionized water so as to remove pollutants on the surface of the substrate, and then is placed in a nitrogen flow for drying.

Step 2): carrying out laser microtexture on the surface of the substrate treated in the step 1) by adopting an ultraviolet nanosecond pulse laser, wherein the selected laser parameters are as follows: the pulse width is 20ns, the laser wavelength is 355nm, the pulse repetition frequency is 30kHz, the laser power is 15W, the pulse energy is 0.5mJ, and the laser power density is 4.0GW/cm²The diameter of the focused effective light spot is about 28 μm, the laser scanning speed is 20mm/s, the laser beam scanning area is 15mm multiplied by 15mm, and the laser preparation substrate is placed in absolute ethyl alcohol for ultrasonic cleaning for 15 minutes.

Step 3): and (3) putting the substrate obtained in the step 2) into a vacuum drying oven for low-temperature heat treatment, wherein the drying oven is not vacuumized in the treatment process, the air is kept smooth, and the substrate is subjected to heat treatment for 2.0 hours at 250 ℃.

Comparative example 3

Step 1): zr based bulk amorphous alloy_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5Cutting into 20mm × 20mm pieces, sequentially ultrasonic cleaning with acetone, anhydrous alcohol, and deionized water for 12 min to remove substrateThe surface contaminants were then blown dry in a stream of nitrogen.

Step 2): carrying out laser microtexture on the surface of the substrate treated in the step 1) by adopting an ultraviolet nanosecond pulse laser, wherein the selected laser parameters are as follows: the pulse width is 20ns, the laser wavelength is 355nm, the pulse repetition frequency is 30kHz, the laser power is 15W, the pulse energy is 0.5mJ, and the laser power density is 4.0GW/cm²The diameter of the focused effective light spot is about 28 μm, the laser scanning speed is 20mm/s, the laser beam scanning area is 15mm multiplied by 15mm, and the laser preparation substrate is placed in absolute ethyl alcohol for ultrasonic cleaning for 15 minutes.

Step 3): and (3) putting the substrate obtained in the step 2) into a vacuum drying oven for low-temperature heat treatment, wherein the drying oven is not vacuumized in the treatment process, the air is kept smooth, and the substrate is subjected to heat treatment for 2.0 hours at the temperature of 300 ℃.

Example 5 wettability determination

The surface wettability of the amorphous alloys prepared in examples 1 to 4 and comparative examples 1 to 3 was measured, and the measuring method was as follows: standing 5 mu L of deionized water on the surface of each alloy, observing and calculating a contact angle by using a static contact angle measuring instrument and a method of a standard number ISO 19403-1:2017, wherein the wettability results of the alloy surface obtained before, after and after laser treatment are shown in Table 1, and the influence of heat treatment on the wettability in the processes of preparing the amorphous alloy surfaces in example 1 and example 3 is shown in figure 1;

table 1: results of measuring surface wettability of amorphous alloy

FIG. 1 shows the transition of the wettability of the amorphous alloy surface after different treatment processes, wherein FIG. 1a is a water drop contact angle image of the untreated amorphous alloy surface, and the water drop contact angle is measured to be 86.4 degrees +/-1.2 degrees, thereby proving that the surface has hydrophilic characteristics. Because the amorphous alloy is in a metastable state structure, the atom bonding state of the surface of the material is weaker, and the atoms are more active compared with the atoms of the same-component crystal, so that the surface energy is higher, and the surface shows hydrophilicity.

When the surface of the amorphous alloy is subjected to laser treatment, as shown in fig. 1b, the surface contact angle is reduced to 0 °, which indicates that the surface of the amorphous alloy after the laser treatment is in a saturated Wenzel state, so that the surface shows a remarkable super-hydrophilic characteristic. Because the laser microtexture obviously increases the micro roughness of the surface of the amorphous alloy, the water drop is converted from an unstable Cassie state to a saturated Wenzel state on a laser-induced microstructure composite interface. Meanwhile, a large number of hydroxyl (-OH) and carboxyl (-COOH) groups generated on the surface are polar groups and have extremely strong hydrophilic characteristics, and the increase of the content of the polar groups also leads to the enhancement of the surface hydrophilicity.

Subsequently, as shown in fig. 1c, when the laser micro-texture amorphous alloy surface is subjected to low-temperature heat treatment for one hour, the surface contact angle is increased to 147.2 ± 1.7 °, and a better hydrophobic characteristic is obtained. Meanwhile, as shown in fig. 1d, after the laser micro-texture amorphous alloy surface is subjected to low-temperature heat treatment for two hours, the surface contact angle reaches 153.8 ± 2.2 degrees, and an obvious super-hydrophobic characteristic is obtained. The above conclusion can prove that the laser microtexture amorphous alloy surface can realize the transformation from the super-hydrophilic characteristic to the super-hydrophobic characteristic after the low-temperature heat treatment for two hours, the main reason is that the super-hydrophobicity of the surface is caused by the deposition of the non-polar hydrophobic group and the silicon-containing film on the surface, and the low-temperature heat treatment process can remarkably accelerate the non-polar hydrophobic group (such as-CH) in the air₂-,-CH₃C ═ C and other functional groups) on the surface of the amorphous alloy, and simultaneously can induce the deposition process of the silicon-containing film to occur, and the two groups jointly act to enable the surface of the amorphous alloy to show better hydrophobicity and even super-hydrophobicity. Meanwhile, from experimental results, the heat treatment temperature, the heat treatment time and the laser parameters all have certain influence on the transformation of the surface wettability. First, a sufficient heat treatment duration must be ensured to ensure that the laser microtextured surface achieves superhydrophobic properties. In this work, the contact angle of the laser microtextured surface was significantly increased when the heat treatment time was 1.0 hour, but the superhydrophobic property was not achieved. When the heat treatment time is longer than 1.5 hours, the realization of the superhydrophobic property of the surface can be ensured. Secondly, the heat treatment temperature must be setAnd controlling within a certain range. In the work, when the heat treatment temperature is between 150 ℃ and 200 ℃, the laser micro-texture surface can realize the super-hydrophobic characteristic. However, when the heat treatment temperature is 250 to 300 ℃, the surface contact angle is not changed before and after the heat treatment, and the transition from the superhydrophilic characteristic to the superhydrophobic characteristic cannot be realized.

In another aspect, laser processing parameters also have some effect on surface wettability. Wettability test results show that when laser processing parameters within this range are used: the wavelength of the laser is 200-400 nm, the pulse repetition frequency is 10-30 kHz, the laser power is 1-15W, the pulse energy is 0.1-0.5 mJ, and the laser power density is 1.0-4.0 GW/cm²The diameter of an effective focused light spot is about 25-30 mu m, the laser scanning speed is 20-80 mm/s, and the contact angle of the laser micro-texture surface can be larger than 150 degrees, so that the super-hydrophobic characteristic is realized. The density of the laser micro-texture surface micro-nano structure obtained by using near-infrared pulse laser (the wavelength of the laser is 1064nm) is lower than that obtained by using ultraviolet pulse laser, the surface contact angle is less than 150 degrees, and the super-hydrophobic characteristic cannot be realized.

EXAMPLE 6 microhardness determination

The microhardness of the surfaces of the amorphous alloys prepared in examples 1-4 and comparative examples 1-3 is measured by adopting a measuring method of ISO 6507-1:2005, and the results obtained by the measuring method are shown in Table 2;

table 2: results of measuring microhardness of surface of amorphous alloy

The results in table 2 show that the microhardness of the microtextured surface obtained by laser treatment is obviously improved compared with the surface which is not subjected to laser treatment, and the microhardness of the microtextured surfaces obtained by laser treatment in the four groups in examples 1 to 4 is improved by 9.8 to 10.6 percent compared with the surface which is not subjected to laser treatment, wherein the microhardness of the laser microtextured surface obtained in example 3 is the highest;

fig. 2 shows the intuitive histogram results of the microhardness tests of the amorphous alloy untreated surface and the laser microtextured surface of example 3, and the test results show that the microhardness of the untreated surface is 516.2 ± 4.6HV, and the microhardness of the microtextured surface with the unidirectional groove structure reaches 570.8 ± 4.9HV through the laser surface microtexture process, which is 10.6% higher than that of the untreated surface.

Meanwhile, the microhardness results obtained by the comparative example 4 and the comparative examples 2 to 3 show that the microhardness of the alloy surface obtained after heat treatment at 200 ℃, 250 ℃ and 300 ℃ has no influence basically. In contrast, in comparative example 3 and comparative example 1, it is found that in comparative example 1, the density of the micro-nano structure on the surface of the laser micro-texture obtained by using near-infrared pulse laser (laser wavelength 1064nm) is reduced to a certain extent, the grain refinement degree is reduced, the grain boundary is reduced, and therefore the final hardness value is relatively low.

Example 7 evaluation of morphological characteristics of amorphous alloy surface

The morphology characteristics of the untreated surface and the laser microtextured surface of the amorphous alloy prepared in example 3 were evaluated, and the surface morphology characteristics obtained at different scanning speeds were observed using an SEM scanning electron microscope, and the obtained results are shown in fig. 3;

from the results of FIG. 3, it can be seen that:

as shown in fig. 3a, the untreated surface has high flatness and low roughness, and only the transverse stripes left after the polishing treatment are visible on the surface, as shown in fig. 3b-e, the laser microtextured surface exhibits a significantly different surface structure;

under the condition of low scanning speed (20mm/s, fig. 3b), the sample surface after laser microtexture has a regularly arranged linear micron-scale convex structure, the period of the linear micron-scale convex structure is 150 μm, some submicron and nanometer-scale particles are distributed between every two micro-convex lines, and the particles are mainly formed by the steps of local temperature rise, vaporization and ionization of the material surface in the interaction process of laser and the material to generate high-pressure plasma expansion and deposition through the actions of material ablation and plasma jet; with increasing laser scanning rate (40mm/s, fig. 3c), a microprotrusion structure was still observed, however the uniformity of the structure was somewhat reduced; as the scan rate continues to increase to 60mm/s (FIG. 3d) and 80mm/s (FIG. 3e), it can be seen that the microtextured surface undergoes a significant change in texture from the previous microprotrusions to a low-medial-height microdepression. Meanwhile, the micro-nano particles distributed among the periodic structures can be clearly observed under different scanning speeds.

The experimental results show that the structural form of the surface can be effectively controlled by controlling the laser parameters, the conversion of the structural form is the result of the combined action of the recoil pressure and the marangoni flow in the interaction process of the laser materials, and the free conversion between the microprotrusion structure and the micro-recessed structure can be realized by reasonably controlling the laser energy density and the laser pulse number (by changing the laser scanning rate regulation). Compared with a near-infrared nanosecond laser with the wavelength of 1064nm, the ultraviolet laser with the wavelength of 355nm is used in the invention, so that the accurate control on the micro-concave structure of the micro-protrusions on the surface of the amorphous alloy is ensured, the heat effect in the laser processing process can be reduced, the heat affected zone is reduced, the high-quality surface micro-nano structure is prepared, and a foundation is laid for the surface functionalization of the amorphous alloy.

In addition, according to the data results of the embodiment 5 and the embodiment 6, the SEM image shows that the periodic micro-nano structure is prepared on the surface of the amorphous alloy by the laser micro-texture processing, so that more refined grains are generated on the surface, and according to the Hall-Petch effect, more grain boundaries are generated while the grains are refined, so that the dislocation movement resistance of the material is enhanced, the surface hardness can be improved, and meanwhile, the surface hardness is further improved by the high-density micro-nano structure.

Example 8 analysis of surface chemical composition of amorphous alloy

Surface chemical composition analysis is performed on the amorphous alloy untreated surface, the laser micro-texture surface and the laser micro-texture surface after heat treatment, which are prepared in example 3, and XPS energy spectrum analysis is adopted to obtain a sample surface chemical composition result shown in FIG. 4;

as shown in FIG. 4a, C, O, Be, Zr, Ti, Ni and Cu elements were detected on the surface of the untreated amorphous alloy. Wherein Be, Zr, Ti, Ni and Cu elements are derived from an amorphous alloy substrate material, O element is derived from the oxidation of the surface layer of the substrate material, and C element is derived from the slight pollution of the surface of the substrate material;

fig. 4b shows that the chemical element composition of the laser microtexture amorphous alloy surface is changed to a certain extent compared with the untreated surface, except that the content of the matrix material elements is changed to a certain extent, the largest change comes from C element and O element, as can be seen from fig. 4b, the content of C element on the surface is obviously reduced after laser treatment, and the content of O element is obviously increased, which indicates that the laser microtexture not only induces the generation of the periodic micro-nano structure on the amorphous alloy surface, but also significantly oxidizes the surface, thereby generating a large amount of hydroxyl (-OH) and carboxyl (-COOH) on the surface;

for the laser microtextured surface after the low-temperature heat treatment, the chemical composition thereof is significantly changed compared with that before the low-temperature heat treatment, and the observation of fig. 4c shows that the chemical change mainly has the following two aspects: firstly, the content of C element on the surface is obviously increased after low-temperature heat treatment, mainly because the low-temperature heat treatment accelerates the nonpolar carbon-containing hydrophobic group (such as-CH) in the air₂-,-CH₃C ═ C and other functional groups) on the surface of the amorphous alloy; secondly, the existence of Si element is detected on the surface of low-temperature heat treatment, the deposition of the Si element comes from a silicon rubber door seal ring on a vacuum drying oven, and in the heat treatment process of 150 ℃, silicon atoms on the silicon rubber door seal ring can be evaporated into the air and then deposited on the surface of amorphous alloy and pass through 5m³The exhaust flow of the gas is that a layer of silicon-containing film is formed on the surface of the alloy, and the carbon-containing hydrophobic group with hydrophobic property and the silicon-containing film are jointly deposited on the laser micro-texture surface after low-temperature heat treatment, so that the surface is promoted to generate super-hydrophobic property.

It should be noted that specific features, structures, materials or characteristics described in this specification may be combined in any combination, all possible combinations of technical features in the above embodiments are not described in order to simplify the description, and those skilled in the art may combine and combine features of different embodiments and features of different embodiments described in this specification without contradiction.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.