High-pressure controllable cavitation jet forming device and method for manufacturing thin-strip microstructures

Abstract

This invention belongs to the field of micro / nano structure manufacturing and forming, specifically relating to a high-pressure controllable cavitation jet forming device and method for manufacturing thin strip microstructures. The high-pressure controllable cavitation jet forming device for manufacturing thin strip microstructures includes a base, an acrylic liquid chamber, and a three-stage cavitation generator. The acrylic liquid chamber is disposed above the base, and an electromagnetic pressure ring is fitted outside the acrylic liquid chamber. The electromagnetic pressure ring is also disposed above the base. The three-stage cavitation generator is disposed inside the acrylic liquid chamber. A forming die is disposed within the base, and the end face of the forming die near the acrylic liquid chamber has several microstructure holes. Magnetic pads are disposed within the base, arranged outside the forming die, and the magnetic force of the magnetic pads is controlled by a current controller. This forming device uses cavitation jets instead of rigid punches, improving contact conditions; the use of a combinable three-stage cavitation generator allows for a wide range of adjustable cavitation intensity.

Description

Technical Field

[0001] This invention belongs to the field of micro-nano structure manufacturing and forming, specifically relating to a high-pressure controllable cavitation jet forming device and method for manufacturing thin strip microstructures. Background Technology

[0002] With the rapid development of technology, the demand for thin / ultra-thin strip devices is increasing across various fields. This often requires designing microstructural features on these devices, such as micron / nanoscale bumps, pores, and textures, which can endow materials with specific functionalities or optimize their performance. For example, in medical devices and waterproof coatings, micron-level trenches or columnar arrays (similar to the surface structure of a lotus leaf) can achieve superhydrophobic or superhydrophilic properties. In the field of mechanics, microcracks or corrugated structures can absorb stress and prevent the strip from breaking when bent, and can be applied to the copper foil of flexible circuit boards. Microstructural design can also increase the contact area with other materials, improving adhesion strength, and so on.

[0003] Currently, the main technologies for manufacturing microstructures on thin / ultra-thin strips include electrochemical processing, photolithography, thin film deposition, laser micro / nano fabrication, and plasma etching. While photolithography, plasma etching, and laser micro / nano fabrication offer high resolution, they suffer from high technical difficulty, high equipment costs, and long processing cycles, limiting their application to cutting-edge fields and hindering their widespread adoption in general industry. Thin film deposition and electrochemical processing are selective in their application, also suffer from long processing cycles and high energy consumption, making it difficult to form microstructures on large-size thin / ultra-thin strips. Therefore, a low-cost, high-efficiency technology for mass-producing microstructures on thin / ultra-thin strips remains elusive.

[0004] Cavitation jet forming technology provides an effective method for the manufacturing / stamping of microstructures in thin / ultra-thin strips. Utilizing the characteristics of small diameter, concentrated energy, and high processing efficiency resulting from the instantaneous collapse of cavitation bubbles, a rationally designed cavitation generator and cavitation energy control device can enable batch processing of various microstructures. While the technology disclosed in Chinese Patent Publication No. CN110614428A, entitled "A Device and Method for Laser-Induced Cavitation Forming," can achieve microforming of metal foils, the microjet intensity is limited, and the cavitation direction and intensity are difficult to adjust. Furthermore, to integrally form microstructure features on a single piece of foil, a large number of laser light sources must be introduced, resulting in unimaginable costs. The technology disclosed in Chinese Patent Publication No. CN107930548A, entitled "A Cavitation Generator Capable of Two-Stage Cavitation,"... While the current technique achieves two-stage cavitation through a combination of a Venturi tube and an orifice plate structure, the orifice plate is not in the optimal position, resulting in limited cavitation intensity. Furthermore, it does not explain how to apply this technique to forming or punching applications. The technology disclosed in Chinese Patent Publication No. CN108890541B, entitled "A Device and Method for Plastic Forming of Micro Parts Using Artificial Submerged Cavitation Jet," further increases the intensity of the cavitation jet by adding abrasive particles. However, its cavitation intensity and jet direction are difficult to control, and it does not have punching forming capabilities. In addition, its device is excessively large. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies, such as the difficulty in controlling the energy and direction of cavitation jets and the easy damage to the surface of formed devices. It provides a high-pressure controllable cavitation jet forming device and method for manufacturing thin strip microstructures. This device uses cavitation jets instead of rigid punches, improving contact conditions and facilitating the plastic flow of thin / ultra-thin strips. The use of a three-stage cavitation generator allows for a wide range of control over cavitation intensity. It is suitable not only for thin / ultra-thin strips of metallic materials such as aluminum alloys, magnesium alloys, titanium alloys, and stainless steel, but also for the manufacturing and stamping of microstructure features of polymers, composite materials, etc.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a high-pressure controllable cavitation jet forming device for manufacturing thin strip microstructures, comprising a base, an acrylic liquid chamber and a three-stage cavitation generator, wherein the acrylic liquid chamber is disposed above the base, and an electromagnetic pressure ring is fitted outside the acrylic liquid chamber, wherein the electromagnetic pressure ring is disposed above the base, and the three-stage cavitation generator is disposed inside the acrylic liquid chamber.

[0007] The base is provided with a forming die. The forming die has several microstructure holes on its end face near the acrylic liquid chamber. Several magnetic pads are provided in the base and are arranged on the outside of the forming die. The magnetic force of the magnetic pads is controlled by a current controller, which is located on the outside of the base.

[0008] The acrylic liquid chamber is filled with working fluid and has openings at both the top and bottom. The bottom of the electromagnetic pressing ring is located between the acrylic liquid chamber and the base. The electromagnetic pressing ring presses and fixes the thin strip located between the forming die and the electromagnetic pressing ring by magnetic attraction with the magnetic pad in the base.

[0009] The three-stage cavitation generator is connected to a seamless steel pipe via a connector. The seamless steel pipe is connected to a high-pressure adjustable water pump via a water supply pipe. The high-pressure adjustable water pump draws water from a water storage tank via a water intake pipe. A pressure regulating valve is installed on the water supply pipe. A pressure relief pipe is also installed between the pressure regulating valve and the water storage tank. A pressure relief valve is installed on the pressure relief pipe.

[0010] The three-stage cavitation generator includes a Venturi cavitation generator, a microporous plate is provided inside the Venturi cavitation generator, and a propeller is provided at the connection between the Venturi cavitation generator and the seamless steel pipe. The propeller, Venturi cavitation generator, microporous plate, acrylic liquid chamber, and forming die are coaxially arranged.

[0011] Preferably, the water storage tank is equipped with a filter, which is connected to a high-pressure adjustable water pump via a water intake pipe.

[0012] Preferably, the base is provided with a cavity groove, and the forming cavity is placed in the cavity groove.

[0013] Preferably, a sealing ring is provided at the location where the electromagnetic pressing ring contacts the acrylic liquid chamber, and a sealing ring is provided at the location where the electromagnetic pressing ring contacts the base.

[0014] Preferably, the seamless steel pipe is fixed by a bracket.

[0015] Preferably, an overflow port is provided at the upper part of the acrylic liquid chamber, and an overflow pipe is provided between the overflow port and the water storage tank.

[0016] Preferably, the three-stage cavitation generator includes two different models with different sizes: large and small; and the microporous plate inside the three-stage cavitation generator is a detachable structure.

[0017] Preferably, a superelastic film is provided between the electromagnetic pressure ring and the forming die, and the superelastic film is fixed to the bottom of the electromagnetic pressure ring.

[0018] A high-pressure controllable cavitation jet forming method for fabricating thin strip microstructures using the above-mentioned apparatus includes the following steps:

[0019] (1) Pre-treatment of blanks: take a thin strip with a diameter of 50-100 mm and a thickness of 10-100 μm and place it coaxially on the forming die;

[0020] (2) Fix the thin strip, put the electromagnetic pressing ring on the outside of the acrylic liquid chamber and make its bottom contact with the thin strip, and adjust the current of the current controller to make the pressing force of the electromagnetic pressing ring reach the requirements.

[0021] (3) Jet preparation: Inject working fluid into the acrylic liquid chamber until it submerges the top of the three-stage cavitation generator, then stop injecting. Turn on the high-pressure adjustable water pump and adjust the pressure regulating valve to achieve the required jet pressure.

[0022] (4) Jet forming: The working fluid is ejected from the three-stage cavitation generator and meets the stationary working fluid in the acrylic liquid chamber, forming a strong shearing effect and further generating a large number of bubbles. The bubbles are impacted at high speed through the openings at the bottom of the acrylic liquid chamber and the electromagnetic pressure ring, forming microstructure features on the thin strip that are consistent with the microstructure hole structure on the forming die. The jet pressure in step (3) is adjusted. When the jet pressure is large enough, a hollow microstructure feature is formed on the thin strip that is consistent with the microstructure hole structure on the forming die.

[0023] Preferably, the working fluid includes water, sodium chloride solution, alcohol, oil, etc.

[0024] The beneficial effects of this invention are as follows:

[0025] 1. Replacing the rigid punch with a cavitation jet avoids hard contact between the rigid punch and the thin / ultra-thin strip, reducing the risk of breakage and wrinkling. On the other hand, replacing the rigid punch with a cavitation jet makes the stress state of the thin / ultra-thin strip more uniform, which is conducive to the formation of more accurate microstructural features in a more stable manner.

[0026] 2. The cavitation intensity can be maximized through the combined action of the propeller, Venturi cavitation generator, and microporous plate in the three-stage cavitation generator. Furthermore, by adjusting the propeller power, regulating the pressure valve of the high-pressure adjustable water pump, and selecting whether to remove the microporous plate, multi-level adjustable cavitation intensity can be achieved. By adjusting the cavitation intensity level, microstructure manufacturing and stamping can be achieved not only for thin / ultra-thin metal strips, but also for the manufacturing and stamping of microstructure features in polymers and composite materials. At lower cavitation intensity, only microstructure feature patterns consistent with the microstructure hole structure on the forming die are formed on the thin / ultra-thin strip. However, if it is necessary to form hollowed-out microstructure features on the thin / ultra-thin strip, the cavitation intensity needs to be increased to achieve the cutting and forming of the microstructure features.

[0027] 3. Electromagnetic edge clamping is used to clamp thin / ultra-thin strips. The clamping force can be adjusted by regulating the current. This adjustment process is characterized by low energy consumption and offers greater convenience and adjustability compared to most spring-driven mechanical edge clamping methods, especially for thin / ultra-thin strips with a thickness of 0.01mm-0.1mm. Furthermore, the electromagnetic edge clamping ring can be vertically displaced, providing a more convenient way to replace thin / ultra-thin strips. Even further, by replacing electromagnetic edge clamping rings with different inner diameters, edge clamping functions for thin / ultra-thin strips of different sizes can be achieved. On the other hand, the super-elastic film placed at the bottom of the electromagnetic edge clamping ring facilitates the punching process and reduces the probability of breakage of the thin / ultra-thin strip during punching.

[0028] 4. At the top side of the acrylic liquid chamber, an overflow pipe connects the overflow port to the water storage tank. When the working fluid exceeds the height of the acrylic liquid chamber's overflow port, the working fluid will flow back to the water storage tank through the overflow pipe. As the device operates, it can continue to participate in subsequent microstructure feature manufacturing and punching processes, achieving fluid recycling.

[0029] 5. The forming die is replaceable, allowing for processing to meet different microstructure and punching requirements of thin / ultra-thin strips. Furthermore, it is equipped with an electromagnetic pressure ring, making replacement simple and easy.

[0030] 6. The seamless steel pipe is connected to the three-stage cavitation generator through connectors to form an integral unit. It is vertically and coaxially fixed in the acrylic liquid chamber by the support and the base. The integral unit can have vertical displacement. By adjusting the displacement, the optimal target distance under different cavitation intensities can be obtained to achieve the best manufacturing and stamping effect of thin strip / ultra-thin strip microstructure features.

[0031] 7. When the working fluid is ejected from the three-stage cavitation generator, it generates a strong shear force with the static fluid in the acrylic liquid chamber, further producing a large number of bubbles and increasing the cavitation intensity. Furthermore, different working fluids, such as water, sodium chloride solution, alcohol, and oil, can be selected as needed to achieve different processing effects.

[0032] 8. Compared to other microstructure feature manufacturing and die-cutting processes, this forming process is adjustable, highly precise, has good orientation, and is convenient and economical. Furthermore, this process is environmentally friendly, producing no pollution during the microstructure feature manufacturing and die-cutting process. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0034] Figure 2 This is a longitudinal cross-sectional view of the three-stage cavitation generator in Example 1;

[0035] Figure 3 This is a longitudinal cross-sectional view of the three-stage cavitation generator in Example 2;

[0036] Figure 4 This is a top view of the forming die in this invention.

[0037] Figure 5 yes Figure 4 Schematic diagram of the cross-sectional structure along line AA in the middle;

[0038] Figure 6 This is a top view of the forming die structure in Example 3;

[0039] Figure 7 yes Figure 6 Schematic diagram of the cross-sectional structure along the BB line in the middle;

[0040] Figure 8 This is a schematic diagram of the connection between the base and the electromagnetic pressure ring in this invention;

[0041] Figure 9 yes Figure 8 A magnified structural diagram at point C.

[0042] Figure label:

[0043] 1. Base; 2. Acrylic liquid chamber; 3. Three-stage cavitation generator; 31. Venturi cavitation generator; 32. Microporous plate; 33. Propeller; 4. Electromagnetic pressure ring; 5. Forming die; 51. Microstructure hole; 6. Magnetic pad; 7. Thin strip; 8. Connector; 9. Seamless steel pipe; 10. Water supply pipe; 11. High-pressure adjustable water pump; 12. Water intake pipe; 13. Water storage tank; 14. Pressure regulating valve; 15. Pressure relief pipe; 16. Pressure relief valve; 17. Filter; 18. Bracket; 19. Overflow port; 20. Overflow pipe; 21. Current controller; 22. Die groove; 23. Ultra-elastic membrane; 24. Sealing ring. Detailed Implementation

[0044] The present invention will now be further described with reference to the accompanying drawings. The following embodiments are only used to illustrate the structure of the present invention more clearly.

[0045] Example 1: As Figure 1As shown, a high-pressure controllable cavitation jet forming device for manufacturing thin strip microstructures includes a base 1, an acrylic liquid chamber 2, and a three-stage cavitation generator 3. The acrylic liquid chamber 2 is positioned above the base 1, and an electromagnetic pressure ring 4 is fitted outside the acrylic liquid chamber 2. The electromagnetic pressure ring 4 is positioned above the base 1, and the three-stage cavitation generator 3 is positioned inside the acrylic liquid chamber 2. The acrylic liquid chamber 2 is filled with working fluid and has openings at both its upper and lower ends. The electromagnetic pressure ring 4 is fitted outside the acrylic liquid chamber 2, with its bottom positioned between the acrylic liquid chamber 2 and the base 1. The electromagnetic pressure ring 4 fixes the thin strip 7 positioned between the forming die 5 and the electromagnetic pressure ring 4 through the magnetic attraction force between the electromagnetic pressure ring 4 and the magnetic pad 6 inside the base 1.

[0046] The three-stage cavitation generator 3 is connected to the seamless steel pipe 9 via a connector 8. The seamless steel pipe 9 is connected to the high-pressure adjustable water pump 11 via a water supply pipe 10. The high-pressure adjustable water pump 11 draws water from the water storage tank 13 via a water intake pipe 12. A pressure regulating valve 14 is installed on the water supply pipe 10. A pressure relief pipe 15 is also installed between the pressure regulating valve 14 and the water storage tank 13. A pressure relief valve 16 is installed on the pressure relief pipe 15. The three-stage cavitation generator 3 includes a Venturi cavitation generator 31. A microporous plate 32 is installed inside the Venturi cavitation generator 31. A propeller 33 is also installed at the connection between the Venturi cavitation generator 31 and the seamless steel pipe 9. The propeller 33 is driven by a motor. The propeller 33, the Venturi cavitation generator 31, the microporous plate 32, the acrylic liquid chamber 2, and the forming die 5 are coaxially arranged.

[0047] A filter 17 is installed inside the water storage tank 13, and the filter 17 is connected to a high-pressure adjustable water pump 11 through a water intake pipe 12. The seamless steel pipe 9 is fixed by a bracket 18, and an overflow port 19 is provided on the upper part of the acrylic liquid chamber 2. An overflow pipe 20 is provided between the overflow port 19 and the water storage tank 13.

[0048] like Figure 4-5 and Figure 8 As shown, a forming die 5 is provided inside the base 1. Several microstructured holes 51 are provided on the end face of the forming die 5 near the acrylic liquid chamber 2. Several magnetic pads 6 are provided inside the base 1, arranged outside the forming die 5. The magnetic force of the magnetic pads 6 is controlled by a current controller 21 located outside the base 1. A die groove 22 is provided inside the base 1, and the forming die 5 is placed inside the die groove 22. The electromagnetic pressing ring 4 is located between the base 1 and the acrylic liquid chamber 2. Figure 6-7 As shown, another type of microstructure feature corresponds to the microstructure hole 51. The shape of the microstructure hole 51 on the end face of the forming die 5 can be changed according to requirements.

[0049] In practical applications, the base 1 is placed flat on the ground, and the forming die 5 and magnetic pad 6 are embedded in the base 1. The forming die 5 can be designed with various shapes of microstructure holes 51 according to forming and punching requirements. The forming die 5 can be designed in various shapes such as cup-shaped, arc-shaped, and trapezoidal, and its shape needs to match the die groove 22 in the base 1. The acrylic liquid chamber 2 has open overflow ports 19 at both the top and bottom, with a height generally around 1000mm. The overflow port 19 is located 800mm from the bottom surface to facilitate the recovery of the working liquid. The electromagnetic pressure ring 4 is also available in several specifications for replacement, with the main difference being the inner diameter of the electromagnetic pressure ring 4. To ensure that the liquid in the acrylic liquid chamber 2 and the electromagnetic pressure ring 4 does not leak, two sealing rings 24 are provided at the contact points between the electromagnetic pressure ring 4 and the acrylic liquid chamber 2, and two sealing rings 24 are also provided at the contact points between the electromagnetic pressure ring 4 and the base 1. Due to drawing size limitations, Figure 8 The sealing ring 24 is only shown at the position where the electromagnetic pressing ring 4 contacts the acrylic liquid chamber 2, while the position where the electromagnetic pressing ring 4 contacts the base 1 is not shown. However, this structure is a conventional and mature technology, which can be obviously understood by those skilled in the art.

[0050] The three-stage cavitation generator 3 includes two different sizes: large and small; and the microporous plate 32 inside the three-stage cavitation generator 3 is a detachable structure.

[0051] like Figure 2 The diagram shows a longitudinal cross-sectional view of a large-scale three-stage cavitation generator 3. In this structure, the propeller 33 has a diameter r1 of 35 mm. The Venturi cavitation generator 31 consists of a contraction section, a throat, and an expansion section from top to bottom. The contraction angle α1 of the contraction section is 45°, and the expansion angle β1 of the expansion section is 8°. The inner diameters E1 at the front end of the contraction section, d1 at the throat, and D1 at the rear end of the expansion section satisfy E1:d1:D1=4:1:4. The throat length is 10 mm. A microporous plate 32 is embedded at the rear end of the throat of the Venturi cavitation generator 31. The microporous plate 32 consists of 29 holes with a diameter ρ1 of 1 mm. The plate thickness δ1 and the hole diameter ρ1 satisfy a ratio of δ1:ρ1=3:1. Conventionally, the distance between the three-stage cavitation generator 3 and the thin strip 7 is 60-75 times the inner diameter of the throat.

[0052] Example 2: Figure 3The diagram shows a longitudinal cross-sectional view of a small-scale three-stage cavitation generator 3. In this structure, the propeller 33 has a diameter r2 of 7 mm. The Venturi cavitation generator 31 consists of a contraction section, a throat, and an expansion section from top to bottom. The contraction angle α2 of the contraction section is 45°, and the expansion angle β2 of the expansion section is 10°. The inner diameter E2 of the front end of the contraction section, the inner diameter d2 of the throat, and the inner diameter D2 of the rear end of the expansion section satisfy E2:d2:D2=8:1:8. The throat length is 2.5 mm. A microporous plate 32 is embedded in the rear end of the expansion section. The microporous plate 32 consists of 37 holes with a diameter ρ2 of 1 mm. The plate thickness δ2 and the hole diameter ρ2 satisfy a relationship of δ2:ρ2=3:1. Conventionally, the distance between the three-stage cavitation generator 3 and the thin strip 7 is 60-75 times the inner diameter of the throat.

[0053] Example 3: Figure 9 As shown, in order to further improve the protection of the thin strip 7, a super-elastic film 23 is provided between the electromagnetic pressure ring 4 and the forming die 5. The super-elastic film 23 is fixed to the bottom of the electromagnetic pressure ring 4 and can be placed according to the forming requirements.

[0054] Example 4: This example is applied to the forming of extremely thin strips, utilizing, as follows Figure 3 A high-pressure controllable cavitation jet forming method for manufacturing thin strip microstructures using the device shown includes the following steps: (1) Select a small three-stage cavitation generator 3, place the micro-perforated plate 32 at the front end of the Venturi cavitation generator 31, connect the small three-stage cavitation generator 3 to the seamless steel pipe 9 through the connector 8, and fix it coaxially in the acrylic liquid chamber 2 through the bracket 18, connect the propeller 33 to the waterproof motor power supply with an electromotive force of 4.5V, and remove the superelastic film 23 at the bottom of the electromagnetic pressure ring 4. Further, move the seamless steel pipe 9 until there is a vertical distance of 175mm between the outlet of the small three-stage cavitation generator 3 and the ultra-thin strip.

[0055] (2) Select an electromagnetic pressing ring 4 with an inner diameter of 40 mm, fit it on the outside of the acrylic liquid chamber 2 to ensure a tight connection, and move the electromagnetic pressing ring 4 up a certain distance. Select an arc-shaped forming die 5 and fix it in the base 1. Cut an ultra-thin strip with a diameter of 50 mm and a thickness of 10 μm, place it coaxially on the forming die 5, install the sealing ring 24 on the upper surface of the base 1, and move the electromagnetic pressing ring 4 down to be close to the ultra-thin strip. Insert the positioning pin, adjust the current of the magnetic pad 6 to the first-level current, and the electromagnetic pressing ring 4 presses the ultra-thin strip tightly under the action of electromagnetic force.

[0056] (3) Fill the water tank 13 with water, place the filter 17 connected to the inlet of the high-pressure adjustable water pump 11 in the water tank 13, and place the overflow pipe 20 connected to the overflow port 19 in the water tank 13. Fill the acrylic liquid chamber 2 with water until the small three-stage cavitation generator 3 is submerged. Turn on the power of the high-pressure adjustable water pump 11 and adjust the pressure regulating valve 14 until the pressure gauge reading points to 20MPa.

[0057] (4) Turn on the high-pressure adjustable water pump 11. The high-pressure water flows to the small three-stage cavitation generator 3 and moves at high speed. After being ejected from the outlet, a large number of bubbles are generated. The ejected high-speed fluid meets the static fluid in the acrylic liquid chamber 2 and generates a strong shearing effect, which further generates more bubbles and increases the cavitation intensity. This process is maintained for about 4 minutes.

[0058] (5) After the microstructure manufacturing is completed, first turn off the power to the high-pressure adjustable water pump 11, open the pressure relief valve 16 to release pressure, and at the same time disconnect the power supply connected to the waterproof motor in the propeller 33. Adjust the current of the magnetic pad 6 to the reverse microcurrent to demagnetize, move the electromagnetic pressure ring 4 up, take out the ultra-thin strip that has completed the microstructure manufacturing process, take out the arc-shaped forming die 5, remove the small three-stage cavitation generator 3, and move the electromagnetic pressure ring 4 down until it lightly touches the base 1 for use in the next microstructure manufacturing.

[0059] Example 5: This example is applied to the forming of thin strips, utilizing, as follows Figure 2 The device shown is a high-pressure controllable cavitation jet forming method for manufacturing thin strip microstructures, specifically including the following steps: (1) Select a large three-stage cavitation generator 3, place the micro-perforated plate 32 at the rear end of the throat of the Venturi cavitation generator 31, connect the large three-stage cavitation generator 3 to the seamless steel pipe 9 through the connector 8, and fix it coaxially in the acrylic liquid chamber 2 through the bracket 18, connect the propeller 33 to the waterproof motor power supply with an electromotive force of 9V, and fix the superelastic film 23 to the bottom of the electromagnetic pressure ring 4. Further, move the seamless steel pipe 9 until the outlet of the large three-stage cavitation generator 3 leaves a vertical distance of 650mm between it and the thin strip.

[0060] (2) Select an electromagnetic pressure ring 4 with an inner diameter of 80 mm, and fit it onto the outside of the acrylic liquid chamber 2 to ensure a tight connection. Move the electromagnetic pressure ring 4 upwards by a certain distance. Select a punching die 5 and fix it in the base 1. Cut a stainless steel strip 7 with a diameter of 100 mm and a thickness of 100 μm, and place it coaxially on the forming die 5. Install the sealing ring 24 on the upper surface of the base 1, and move the electromagnetic pressure ring 4 down to be close to the strip 7. Insert the positioning pin, adjust the current of the magnetic pad 6 to the third level, and the electromagnetic pressure ring 4 presses the strip 7 tightly under the action of electromagnetic force.

[0061] (3) Inject working fluid into the water storage tank 13, place the filter 17 connected to the inlet of the high-pressure adjustable water pump 11 into the water storage tank 13, and place the overflow pipe 20 connected to the overflow port 19 into the water storage tank 13. Fill the acrylic liquid chamber 2 with water until it submerges the large three-stage cavitation generator 3. Turn on the power to the high-pressure adjustable water pump 11 and adjust the pressure regulating valve 14 until the pressure gauge reading points to 50 MPa.

[0062] (4) Turn on the high-pressure adjustable water pump 11. The high-pressure water flows to the large three-stage cavitation generator 3 and moves at high speed. After being ejected from the outlet, a large number of bubbles are generated. The ejected high-speed fluid meets the static fluid in the acrylic liquid chamber 2 and generates a strong shearing effect, which further generates more bubbles and increases the cavitation intensity. This process is maintained for about 4 minutes.

[0063] (5) After the blanking is completed, first turn off the power of the high-pressure adjustable water pump 11, open the pressure relief valve 16 to release the pressure, and at the same time disconnect the power supply connected to the motor in the propeller 33. Adjust the current of the magnetic pad 6 to the reverse micro current to demagnetize, move the electromagnetic pressure ring 4 up, take out the stainless steel strip 7 that has completed the blanking process, take out the blanking die 5, remove the large three-stage cavitation generator 3, and move the electromagnetic pressure ring 4 down until it lightly touches the base 1 for the next blanking.

[0064] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A high-pressure controllable cavitation jet forming apparatus for fabricating thin strip microstructures, characterized in that: The device includes a base, an acrylic liquid chamber, and a three-stage cavitation generator. The acrylic liquid chamber is positioned above the base, and an electromagnetic pressure ring is fitted around the outside of the acrylic liquid chamber. The electromagnetic pressure ring is also positioned above the base. The three-stage cavitation generator is located inside the acrylic liquid chamber. The base contains a forming die, and the end face of the forming die near the acrylic liquid chamber has several microstructured holes. Several magnetic pads are disposed within the base, arranged outside the forming die. The magnetic force of the magnetic pads is controlled by a current controller located on the outside of the base. The acrylic liquid chamber is filled with working fluid and is open at both the top and bottom. The bottom of the electromagnetic pressing ring is positioned between the acrylic liquid chamber and the base, with an opening in the center of the bottom. The electromagnetic pressing ring uses the magnetic attraction force between itself and the magnetic pad inside the base to press and fix the thin strip positioned between the forming die and the electromagnetic pressing ring. The three-stage cavitation generator is connected to a seamless steel pipe via a connector. The seamless steel pipe is connected to a high-pressure adjustable water pump via a water supply pipe. The high-pressure adjustable water pump draws water from a reservoir via a water intake pipe. A pressure regulating valve is installed on the water supply pipe. A pressure relief pipe is also installed between the pressure regulating valve and the reservoir, and a pressure relief valve is installed on the pressure relief pipe. The three-stage cavitation generator includes a Venturi cavitation generator, a microporous plate is provided inside the Venturi cavitation generator, and a propeller is also provided at the connection between the Venturi cavitation generator and the seamless steel pipe. The propeller is driven by a motor, and the propeller, Venturi cavitation generator, microporous plate, acrylic liquid chamber, and forming die are coaxially arranged. A sealing ring is provided at the location where the electromagnetic pressing ring contacts the acrylic liquid chamber, and a sealing ring is provided at the location where the electromagnetic pressing ring contacts the base. The three-stage cavitation generator includes two different models, large and small; and the microporous plate inside the three-stage cavitation generator is a detachable structure.

2. The high-pressure controllable cavitation jet forming apparatus for manufacturing thin strip microstructures according to claim 1, characterized in that: The water storage tank is equipped with a filter, which is connected to a high-pressure adjustable water pump via a water intake pipe.

3. The high-pressure controllable cavitation jet forming apparatus for manufacturing thin strip microstructures according to claim 1, characterized in that: The base is provided with a cavity groove, and the forming cavity is placed in the cavity groove.

4. The high-pressure controllable cavitation jet forming apparatus for manufacturing thin strip microstructures according to claim 1, characterized in that: The seamless steel pipe is fixed by a bracket.

5. The high-pressure controllable cavitation jet forming apparatus for manufacturing thin strip microstructures according to claim 1, characterized in that: An overflow port is provided at the top of the acrylic liquid chamber, and an overflow pipe is provided between the overflow port and the water storage tank.

6. The high-pressure controllable cavitation jet forming apparatus for fabricating thin strip microstructures according to claim 1, characterized in that: A superelastic film is provided between the electromagnetic pressure ring and the forming die, and the superelastic film is fixed to the bottom of the electromagnetic pressure ring.

7. A high-pressure controllable cavitation jet forming method for manufacturing thin strip microstructures using the high-pressure controllable cavitation jet forming apparatus for manufacturing thin strip microstructures as described in any one of the preceding claims, characterized in that: Includes the following steps: (1) Pre-treatment of blanks: take a thin strip with a diameter of 50-100 mm and a thickness of 10-100 μm and place it coaxially on the forming die; (2) Fix the thin strip, put the electromagnetic pressing ring on the outside of the acrylic liquid chamber and make its bottom contact with the thin strip, and adjust the current of the current controller to make the pressing force of the electromagnetic pressing ring reach the requirements. (3) Jet preparation: Inject working fluid into the acrylic liquid chamber until it submerges the top of the three-stage cavitation generator, then stop injecting. Turn on the high-pressure adjustable water pump and adjust the pressure regulating valve to achieve the required jet pressure. (4) Jet forming: The working fluid is ejected from the three-stage cavitation generator and meets the static working fluid in the acrylic liquid chamber, forming a strong shearing effect to further generate a large number of bubbles. These bubbles then impact the thin strip at high speed through the openings at the bottom of the acrylic liquid chamber and the electromagnetic pressure ring, forming microstructure features on the thin strip that are consistent with the microstructure hole structure on the forming die. Alternatively, a microstructure feature with a hollow shape, consistent with the microstructure hole structure on the forming die, may be formed on the thin strip.

8. The high-pressure controllable cavitation jet forming method for fabricating thin strip microstructures according to claim 7, characterized in that: The working fluid includes water, sodium chloride solution, alcohol, and oil.

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