Microtexture metal surface preparation method based on biological jet flow and heat transfer printing

Abstract

The invention provides a micro-texture metal surface preparation method based on biological jet flow and heat transfer printing, belongs to the technical field of surface engineering, and aims to efficiently prepare a textured metal surface with a functional micro-structure at low cost. A micro-texture metal surface preparation method based on biological jet flow and heat transfer printing comprises the steps that S1, microorganisms are subjected to enlarged culture, and the strong oxidizing property of a culture solution is improved; s2, dust and dirt layers on the metal surface are removed; s3, preparing a mask pattern on the metal surface by adopting a thermal transfer printing technology; and S4, a micro structure is machined on the metal surface through the biological jet technology, and the micro-texture surface is obtained. The metal micro-texture surface preparation method has the advantages of being environmentally friendly, low in consumption, simple in machining process and good in machining sustainability.

Description

Technical Field

[0001] The invention belongs to the technical field of surface texturing, and in particular relates to a method for preparing a micro-textured metal surface based on biojet and thermal transfer. Background Art

[0002] Microtextured metal surface refers to the construction of micrometer or nanometer-scale textured structures on the surface of metal materials, such as grooves, columnar arrays, holes, etc., thereby changing the physical and chemical properties of the surface. These microtextures give metal materials unique properties, such as controllable wettability, which can achieve super-hydrophobicity or super-hydrophilicity; in terms of heat dissipation performance, it can enhance heat transfer; in terms of tribological properties, it can achieve friction and drag reduction; in addition, it can also improve biocompatibility and enhance antibacterial properties. These excellent properties make microtextured metal surfaces show great application potential in the fields of microfluidics, biomedicine, electronic device heat dissipation, mechanical manufacturing, and antibacterial materials.

[0003] People have made many attempts to prepare micro-textured metal surfaces. For example, patent CN112140452A discloses a method for manufacturing an anti-icing surface with a recessed micro-nano dual-stage structure. This method uses precision milling technology to prepare a recessed microstructure on the metal surface, but its processing may cause damage to the metal surface and stress concentration. For example, patent CN110408977A discloses a multi-scale enhanced boiling surface and a composite preparation method thereof. An electrochemical method is used to prepare a honeycomb microstructure on the metal surface, but the method has a complex processing technology and is prone to produce chemical waste liquid during the processing, which may have an impact on the environment. In addition, patent CN118218774A discloses a method for preparing a super-mercury-repellent silver surface using nanosecond laser technology. This method uses laser technology to prepare a microporous structure array on the metal surface, but the equipment price of this method is high and the energy consumption during the processing is too high.

[0004] In summary, there is an urgent need to develop a method for preparing micro-textured metal surfaces with small surface residual stress, low-consumption and environmentally friendly processing, simple and convenient process, and low cost, so as to overcome the shortcomings of existing technologies and meet practical application needs. Summary of the invention

[0005] The main technical problem to be solved by the present invention is to provide a method for preparing a micro-textured metal surface based on biojet and thermal transfer, which has small surface residual stress, low consumption and environmental protection in the processing process, simple and convenient process and low cost.

[0006] In order to solve the above technical problems, the present invention provides a method for preparing a micro-textured metal surface based on biojet and thermal transfer, comprising the following steps:

[0007] S1. Microbial expansion culture improves microbial activity and oxidative properties of culture fluid;

[0008] S2. Remove dust and dirt from the metal surface;

[0009] S3. Designing a pattern with a regular arrangement and transferring it to a thermal transfer paper, and using a thermal transfer technique to transfer the textured pattern on the transfer paper to the metal surface treated in step S2 to generate a mask surface;

[0010] S4. Using biojet processing to process a microstructure on the metal material having a masked surface after being processed in step S3.

[0011] In a preferred embodiment, the microorganisms in step S1 include Thiobacillus ferrooxidans and Thiobacillus thiooxidans.

[0012] In a preferred embodiment, the culture solution components in step S1 include the number of microorganisms and the concentration of metabolites.

[0013] In a preferred embodiment, the cleaning method in step S2 includes grinding, polishing, washing and drying.

[0014] In a preferred embodiment, the metal material in step S2 is a pure metal material, a metal alloy material, or a metal sintered material, the oxidizability of some or all of its components being lower than that of the microbial transformation product.

[0015] In a preferred embodiment, the components of the metal material include but are not limited to iron, cobalt, copper, and tin.

[0016] In a preferred embodiment, the mask pattern in step S3 is a combination of microstructure shapes and arrangements with regular arrangement;

[0017] The graphics include circles and rectangles, and the patterns include but are not limited to rectangles, sinusoids, and hexagons.

[0018] In a preferred embodiment, the image transfer device includes a laser printer or an inkjet printer.

[0019] In a preferred embodiment, in step S3, the mask material does not react with the oxidizing material and is closely attached to the metal substrate;

[0020] The masking material includes carbon powder, resin powder and toner.

[0021] In a preferred embodiment, the weak oxidizing substances produced in the solution after the reaction in step S4 are converted back into strong oxidizing substances through biochemical reactions in the microorganisms.

[0022] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0023] Compared with the traditional masking method, the thermal transfer texture masking method used in the present invention does not require complicated processes such as photolithography and development. Surface masking can be performed on the metal surface through simple heating and pressurization, and the manufacturing process is simple.

[0024] Compared with the traditional micro-texturing processing method, the present invention utilizes the strong oxidizing substances produced by microorganisms to react with metals to achieve material removal, which has the characteristics of simple process, low cost, low energy consumption, and low damage;

[0025] The introduction of jet technology increases the contact frequency between strong oxidizing substances and metal surfaces, thereby improving the processing efficiency of textured surfaces; the weak oxidizing substances produced in the solution after the reaction can be converted into strong oxidizing substances through biochemical reactions in microorganisms, thus realizing the processing cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A flow chart of a method for preparing a micro-textured metal surface based on biofluidics and thermal transfer according to the present invention;

[0027] Figure 2 Schematic diagram of the size and arrangement of the mask patterns designed in Embodiment 1 and Embodiment 2 of the present invention;

[0028] Figure 3 3D topography of the brass micro-protrusion surface in Example 1 of the present invention;

[0029] Figure 4 for Figure 3 Cross-sectional view of the three-dimensional morphology of the micro-protrusions;

[0030] Figure 5 3D topography of the brass micro-protrusion surface in Example 2 of the present invention;

[0031] Figure 6 for Figure 5 Cross-sectional view of the three-dimensional morphology of the microprotrusions. DETAILED DESCRIPTION

[0032] In order to make the technical solutions and features of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific examples. It should be understood that these examples are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0033] Example 1

[0034] This embodiment provides a method for preparing a super-hydrophobic metal surface based on biofluidics and thermal transfer, comprising the following steps:

[0035] S1. The microorganism used in the embodiment is Thiobacillus ferrooxidans. The activity of the primary strain is low, and it is necessary to use expanded culture to improve its biological activity. Different volumes of 100ml, 500ml, 2000ml, and 10000ml are set to gradually improve the activity of the microorganism. The ingredients of the microbial culture solution include 30g / L ammonium sulfate, 5g / L magnesium sulfate heptahydrate, 5g / L dipotassium hydrogen phosphate, 1g / L potassium chloride, 0.144g / L calcium nitrate twenty-tetrahydrate, 248.2g / L ferrous sulfate heptahydrate, and the pH of the culture solution is adjusted to 1.8 using dilute sulfuric acid. The Thiobacillus ferrooxidans strain is inoculated into the culture solution and air is passed through it. The culture is cultured in a constant temperature shaker for 20h at a temperature of 30°C and a shaker speed of 180rpm. The concentration of total iron ions in the bacterial solution is finally obtained to be 5.5g / L, and it is necessary to ensure that Fe 2+ Most of it is converted into Fe 3+ , according to Fe 2+ with Fe 3+ The color characteristics in different solutions are used to determine whether the conversion is complete by titration.

[0036] S2. The metal is H62 brass with a diameter of φ=25 and a height of h=10 mm. It is polished with 400, 1000, and 2000 mesh metallographic sandpapers to remove oil and grease from the surface. The metal material is then ultrasonically cleaned with experimental pure water and anhydrous ethanol, and a smooth metal surface is obtained after drying.

[0037] S3, using thermal transfer technology to generate a textured transfer toner mask on the metal surface treated in step S2. First, a circular convex pattern with a regular hexagonal arrangement is designed on a computer drawing software. The diameter of the circle is φ300μm, the center spacing is 500μm, and the circles are arranged in a regular hexagon. The schematic diagram of the processing microstructure size is as follows: Figure 2 Then, a laser printer is used to print the pattern on the thermal transfer paper to form a layer of carbon powder, and the textured carbon powder on the thermal transfer paper is removed and transferred to the metal surface by heating and pressurizing to complete the textured transfer carbon powder mask.

[0038] S4. Using jet technology, the supernatant containing strong oxidizing substances is sprayed onto the metal surface having the textured transfer carbon powder mask after step S3 to process a metal surface having a functional microstructure. The jet speed is 2 m / s and the processing time is 30 min.

[0039] Example 2

[0040] S1. The microorganism used in the embodiment is Thiobacillus ferrooxidans. The activity of the primary strain is low, and it is necessary to use expanded culture to improve its biological activity. Different volumes of 100ml, 500ml, 2000ml, and 10000ml are set to gradually improve the activity of the microorganism. The ingredients of the microbial culture solution include 30g / L ammonium sulfate, 5g / L magnesium sulfate heptahydrate, 5g / L dipotassium hydrogen phosphate, 1g / L potassium chloride, 0.144g / L calcium nitrate twenty-tetrahydrate, 248.2g / L ferrous sulfate heptahydrate, and the pH of the culture solution is adjusted to 1.8 using dilute sulfuric acid. The Thiobacillus ferrooxidans strain is inoculated into the culture solution and air is passed through it. The culture is cultured in a constant temperature shaker for 20h at a temperature of 30°C and a shaker speed of 180rpm. The concentration of total iron ions in the bacterial solution is finally obtained to be 5.5g / L, and it is necessary to ensure that Fe 2+ Most of it is converted into Fe 3+ , according to Fe 2+ with Fe 3+ The color characteristics in different solutions are used to determine whether the conversion is complete by titration.

[0041] S2. The metal is H62 brass with a diameter of φ=25 and a height of h=10 mm. It is polished with 400, 1000, and 2000 mesh metallographic sandpapers to remove oil and grease from the surface. The metal material is then ultrasonically cleaned with experimental pure water and anhydrous ethanol, and a smooth metal surface is obtained after drying.

[0042] S3, using thermal transfer technology to generate a textured transfer toner mask on the metal surface treated in step S2. First, a circular convex pattern with a regular hexagonal arrangement is designed on a computer drawing software. The diameter of the circle is φ300μm, the center spacing is 500μm, and the circles are arranged in a regular hexagon. The schematic diagram of the processing microstructure size is as follows: Figure 2 Then, a laser printer is used to print the pattern on the thermal transfer paper to form a layer of carbon powder, and the textured carbon powder on the thermal transfer paper is removed and transferred to the metal surface by heating and pressurizing to complete the textured transfer carbon powder mask.

[0043] S4. Using jet technology, the supernatant containing strong oxidizing substances is sprayed onto the metal surface having the textured transfer carbon powder mask after step S3 to process a metal surface having a functional microstructure. The jet speed is 3 m / s and the processing time is 30 min.

[0044] The above is only a specific implementation of the present invention, but the design concept of the present invention is not limited to this. Any non-substantial changes to the present invention using this concept shall be deemed as an infringement of the protection scope of the present invention.

Claims

1. A method for preparing a micro-textured metal surface based on biofluidics and thermal transfer, characterized in that The steps include: S1. Microbial expansion culture improves microbial activity and oxidative properties of culture fluid; S2. Remove dust and dirt from the metal surface; S3. Designing a pattern with a regular arrangement and transferring it to a thermal transfer paper, and using a thermal transfer technique to transfer the textured pattern on the transfer paper to the metal surface treated in step S2 to generate a mask surface; S4. Using biojet processing to process a microstructure on the metal material having a masked surface after being processed in step S3.

2. The preparation method according to claim 1, characterized in that: The microorganisms in step S1 include Thiobacillus ferrooxidans and Thiobacillus thiooxidans.

3. The method for preparing a micro-textured metal surface based on biofluidics and thermal transfer according to claim 1, characterized in that: The culture solution components in step S1 include the number of microorganisms and the concentration of metabolites.

4. The method for preparing a micro-textured metal surface based on biofluidics and thermal transfer according to claim 1, characterized in that: The cleaning method in step S2 includes grinding, polishing, washing and drying.

5. The method for preparing a micro-textured metal surface based on biofluidics and thermal transfer according to claim 1, characterized in that: The metal material in step S2 is a pure metal material, a metal alloy material, or a metal sintered material, the oxidizability of some or all of its components being lower than that of the microbial transformation product.

6. The method for preparing a micro-textured metal surface based on biofluidics and thermal transfer according to claim 1, characterized in that: The components of the metal material include but are not limited to iron, cobalt, copper and tin.

7. The method for preparing a micro-textured metal surface based on biofluidics and thermal transfer according to claim 1, characterized in that: The mask pattern in step S3 is a combination of microstructure shapes and arrangements with regular arrangement; The graphics include circles and rectangles, and the patterns include but are not limited to rectangles, sinusoids, and hexagons.

8. The method for preparing a micro-textured metal surface based on biofluidics and thermal transfer according to claim 1, characterized in that: The image transfer device includes a laser printer and an inkjet printer.

9. The method for preparing a micro-textured metal surface based on biofluidics and thermal transfer according to claim 1, characterized in that: In step S3, the mask material does not react with the oxidizing material and is closely attached to the metal substrate; The masking material includes carbon powder, resin powder and toner.

10. The method for preparing a micro-textured metal surface based on biofluidics and thermal transfer according to claim 1, characterized in that: The weak oxidizing substances produced in the solution after the reaction in step S4 are converted back into strong oxidizing substances through biochemical reactions in the microorganisms.

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