Large-area surface multistage complex microstructure composite forming device and method

Abstract

The application discloses a large-area surface multistage complex microstructure composite forming device, which comprises an electric-field-assisted micro-roller pressure forming mechanism and an electric-field-assisted micro-die pressure forming mechanism. The electric-field-assisted micro-roller pressure forming mechanism comprises a pulse power supply and feeding mechanism, rough rolling roller, fine rolling roller and discharging mechanism arranged in sequence along a conveying direction. The electric-field-assisted micro-die pressure forming mechanism comprises a die pressure forming mechanism and a pressure device arranged above the die pressure forming mechanism. The die pressure forming mechanism comprises a punch and a blank groove arranged below the punch, and the bottom end of the punch is provided with a plurality of microstructures. The forming device adopts the rough rolling roller and the fine rolling roller of the electric-field-assisted micro-roller pressure forming mechanism and the pulse power supply, so that the material surface is subjected to twice roller pressure forming under heating condition, and a basic structure is obtained. Then, the punch is used for forming a multistage complex microstructure of the material, and is suitable for the technical field of mechanical processing and plastic micro-forming.

Description

Technical Field

[0001] This invention belongs to the field of machining and plastic microforming technology, and in particular relates to a composite forming device and method for large-area surface multi-level complex microstructures. Background Technology

[0002] Vapor chamber technology is a heat dissipation technology developed based on vacuum chamber vapor chamber heat dissipation technology, also known as a flat plate heat pipe. The overall thickness of a miniature vapor chamber is generally less than 2mm, significantly increasing the heat transfer area with heat-generating components and better utilizing the heat transfer capacity of the heat pipe. It has great application potential, particularly in the heat dissipation of high-density electronic devices in space satellites. Miniature vapor chambers in the space environment are mainly manufactured using materials such as aluminum, nickel, titanium, and their alloys. The processing methods for capillary wicks primarily include etching, micro-electrical discharge machining, and micromachining. These micromachining technologies have limitations in processing efficiency, the types of materials that can be processed, and the types of parts that can be produced, making it difficult to meet the requirements of capillary structure manufacturing.

[0003] Plastic microforming is a micro-manufacturing technology that uses plastic deformation to form micro-components. It has the characteristics of simple process, high efficiency, good repeatability, high part precision and excellent mechanical properties. Among them, surface microstructure plastic forming technology, mainly based on micro molding technology and micro rolling technology, has become an important processing method for large-area surface microstructures.

[0004] Chinese invention patent "A device and method for cross-scale molding of large-area array microstructures" (Announcement No. CN114260351B) effectively solves the technical problems of difficulty in filling blanks and venting difficulties in the molding process of large-area multi-scale array microstructures. Chinese invention patent "A microchannel plate with dual properties and its composite molding process and equipment" (Announcement No. CN114192797B) uses pulsed current-assisted micro-roll forming of composite material blanks to obtain microchannel structures. Chinese invention patent "A longitudinal roll forming device and method for fuel cell metal electrode plate flow channels" (Announcement No. CN110125216B) uses pre-formed straight flow channels and secondary-formed U-shaped flow channels to increase the flow channel depth, avoid cracking, and reduce springback.

[0005] However, the aforementioned micro-molding and micro-roll forming are mainly aimed at some simple and easily deformable materials. As the characteristic size of the capillary structure of the steam cavity continues to decrease, the scale range continues to expand, and the types of materials increase, it is difficult for micro-roll forming and micro-molding technology, which rely solely on the mold to apply the force field and the heat source to provide the heat field, to manufacture large-area surface microstructures that meet the scale and precision requirements.

[0006] Therefore, there is an urgent need for a device for the efficient fabrication of multi-level complex microstructures on large-area surfaces of difficult-to-deform materials. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a composite forming device for large-area surface multi-level complex microstructures. This forming device employs a coarse and fine roll in an electric field-assisted micro-roll forming mechanism, along with a pulsed power supply, to perform two roll forming processes on the material surface under heating conditions to obtain a basic structure. Then, using a punch combined with the pulsed power supply, microstructures are formed on the material with the basic structure, solving the problem that existing technologies struggle to manufacture large-area microstructures that meet dimensional and precision requirements on the surface of difficult-to-deform materials.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is: a composite forming device for large-area surface multi-level complex microstructures, characterized in that it includes an electric field-assisted micro-roll forming mechanism and an electric field-assisted micro-molding forming mechanism. The electric field-assisted micro-roll forming mechanism includes a pulse power supply and a feeding mechanism, a roughing roll, a finishing roll, and a blanking mechanism arranged sequentially along the conveying direction. The electric field-assisted micro-molding forming mechanism includes a molding mechanism and a pressure device located above the molding mechanism. The molding mechanism includes a punch and a blank groove arranged below the punch. The bottom end of the punch has several microstructures.

[0009] The above-mentioned composite forming device for large-area surface multi-level complex microstructure is characterized in that the roughing roll is composed of an upper roughing roll and a lower roughing roll, the finishing roll is composed of an upper finishing roll and a lower finishing roll, the pulse power supply is connected to the upper roughing roll and the lower finishing roll through a wire, a plurality of first structures are formed on the rolling surface of the upper roughing roll, and a plurality of second structures are formed on the rolling surface of the upper finishing roll.

[0010] The above-mentioned composite forming device for large-area surface multi-level complex microstructures is characterized in that the surface roughness of the second structure is higher than that of the first structure.

[0011] The above-mentioned composite forming device for large-area surface multi-level complex microstructures is characterized in that: an upper insulating plate is connected to the top of the punch; an upper template is fixedly connected to the top of the upper insulating plate; guide posts are connected to both sides of the upper template via guide sleeves; a punch is provided on the upper template; a pressure device is provided at the top of the punch; a pad is fixedly connected to the bottom of the blank groove; a lower insulating plate is fixedly connected to the bottom of the pad; a lower template is fixedly connected to the bottom of the lower insulating plate; and the lower template is connected to the lower end of the guide posts via guide sleeves; both the pad and the punch are connected to a pulse power supply via wires.

[0012] The above-mentioned composite forming device for large-area surface multi-level complex microstructure is characterized in that a limiting post is arranged inside the punch, and the bottom of the limiting post protrudes from the bottom surface of the punch.

[0013] This invention also discloses a method for composite forming of large-area surface multi-level complex microstructures, characterized in that, utilizing the aforementioned composite forming device for large-area surface multi-level complex microstructures, the forming method includes the following steps:

[0014] Step 1: After pre-processing the front end of the blank to be formed with a slope, place it on the feeding mechanism, adjust the roll gap of the roughing roll and the finishing roll, start the feeding mechanism, the roughing roll and the finishing roll, and insert the front end of the blank to be formed into the roughing roll and the finishing roll, ensuring that the roughing roll and the finishing roll are in close contact with the blank to be formed at the same time to form an electrical circuit.

[0015] Step 2: Use a pulse power supply to heat the blank to be formed in Step 1, which has formed an electrical circuit. After reaching the roll forming temperature, roll forming of the basic structure is performed to obtain the blank. Then turn off the pulse power supply.

[0016] Step 3: After trimming the blank obtained in Step 2, place it into the blank slot and control the pressure device to move downward to drive the punch downward, so that the punch and the blank slot press the blank together.

[0017] Step 4: Use a pulse power supply to heat the blank pressed by the punch in step 3. After reaching the molding temperature, hold it at that temperature. Then, the punch continues to move downward to apply force to the blank, causing the blank to undergo graded molding deformation. After molding is completed, turn off the pulse power supply and wait for it to cool to obtain the part.

[0018] The above-mentioned method for composite forming of multi-level complex microstructures on a large surface is characterized in that the material of the blank to be formed in step one is one of magnesium and magnesium alloys, titanium and titanium alloys, nickel-based high-temperature alloys, refractory alloys, high-entropy alloys and steel, and the gap between the finishing rolls is 1.01 to 1.15 times the gap between the roughing rolls.

[0019] By setting the gap between the finishing rolls to 1.01 to 1.15 times that of the roughing rolls, this invention can eliminate the springback generated after the first structure is rolled during the finishing roll pressing process, while simultaneously achieving the shaping of the dimensions and surface accuracy of the first structure.

[0020] The above-mentioned method for composite forming of large-area surface multi-level complex microstructures is characterized in that the pulse parameters of the pulse power supply heating in step two are: frequency 100Hz~3000Hz, current density 50A / mm². 2 ~300A / mm 2 The roll forming temperature is 50℃~400℃.

[0021] This invention sets the pulse parameters of the pulse power supply according to the material and size of the blank to be formed. The higher the material strength, the greater the current density; the smaller the part size, the lower the current density and the higher the frequency.

[0022] The above-mentioned method for composite forming of large-area surface multi-level complex microstructures is characterized in that the pulse parameters of the pulse power supply heating in step four are: frequency 100Hz~1000Hz, current density 50A / mm². 2 ~500A / mm 2 The molding temperature is 100℃~700℃, and the holding time is 2min~10min.

[0023] The present invention sets the pulse parameters of the pulse power supply according to the material and size of the blank to be formed. In step four, the compression molding has a lower frequency, higher current density and higher forming temperature compared with the roll forming in step two.

[0024] The above-mentioned method for composite forming of multi-level complex microstructures on a large surface is characterized in that the graded molding deformation in step four involves dividing the multi-level complex microstructure into several microstructures, and performing multiple molding deformations by replacing the punch with the corresponding microstructure at the bottom end to obtain a part with a multi-level complex microstructure.

[0025] This invention employs a graded molding deformation process, which enables the re-molding of the previous microstructure during the subsequent molding process, effectively improving the formability and precision of multi-level complex microstructures.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] 1. This invention combines an electric field-assisted micro-roll forming mechanism and an electric field-assisted micro-molding forming mechanism to achieve large-area multi-level complex microstructure forming on the material surface. By using a coarse roll and a fine roll and a pulse power supply set in the electric field-assisted micro-roll forming mechanism, the material surface is subjected to two roll forming under heating conditions to obtain the basic structure, thereby reducing the difficulty of subsequent multi-level complex microstructure forming. Then, by using a punch for micro-molding on the basic structure, the precision forming of multi-level complex microstructures is achieved.

[0028] 2. This invention improves the machinability of difficult-to-deform materials by setting a pulse power supply and utilizing the adjustable energy, time, and location of the pulse current to heat materials at specific points, thereby achieving control over the microstructure and mechanical properties of the materials.

[0029] 3. By employing a multi-step graded forming method, this invention distributes the concentrated stress / strain generated during the forming process of multi-level complex microstructures to each step, thereby improving the uniformity of deformation, suppressing the generation of forming defects and reducing deformation springback, and thus improving the geometric accuracy and mechanical properties of the material; at the same time, it can improve the dimensional accuracy of multi-level complex microstructures and realize the processing of micron-level multi-level complex microstructures on the material surface.

[0030] 4. The forming method of multi-level complex microstructures of the present invention is low in cost, low in energy consumption, and can be mass-produced.

[0031] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the electric field-assisted micro-roll forming mechanism of the present invention.

[0033] Figure 2 This is a schematic diagram of the electric field-assisted micro-molding mechanism of the present invention.

[0034] Figure 3 for Figure 2 Enlarged view of point A.

[0035] Figure 4 This is a schematic diagram of the cross-sectional structure of the first structure in Embodiment 2 of the present invention.

[0036] Figure 5 This is a schematic diagram of the cross-sectional structure of the second structure in Embodiment 2 of the present invention.

[0037] Figure 6 This is a cross-sectional schematic diagram of several levels of punch microstructures in Embodiment 3 of the present invention.

[0038] Explanation of reference numerals in the attached figures:

[0039] 1—Pulse power supply; 2—Feeding mechanism; 3—Unloading mechanism;

[0040] 4—Punch; 4-1—Upper insulating plate; 4-2—Upper template;

[0041] 4-3—Punch; 4-4—Limit pin; 5—Blank slot;

[0042] 5-1—Backing plate; 5-2—Lower insulation plate; 5-3—Lower template;

[0043] 6—Upper coarsening roll; 6-1—First structure; 7—Lower coarsening roll;

[0044] 8—Upper finishing roller; 8-1—Second structure; 9—Lower finishing roller;

[0045] 10—Guide post; 10-1—Guide sleeve; 11—Blank to be formed;

[0046] 12—Blank; 13—Wire. Detailed Implementation

[0047] The large-area surface multi-level complex microstructure composite forming device of the present invention is described in detail through Examples 1 to 3.

[0048] Example 1

[0049] like Figure 1 and Figure 2 As shown, the forming apparatus of this embodiment includes an electric field-assisted micro-roll forming mechanism and an electric field-assisted micro-molding forming mechanism. The electric field-assisted micro-roll forming mechanism includes a pulse power supply 1 and a feeding mechanism 2, a roughing roll, a finishing roll and a blanking mechanism 3 arranged sequentially along the conveying direction. The electric field-assisted micro-molding forming mechanism includes a molding mechanism and a pressure device located above the molding mechanism. The molding mechanism includes a punch 4 and a blank groove 5 arranged below the punch 4. The bottom end of the punch 4 has several microstructures.

[0050] In practical use, this embodiment uses an electric field-assisted micro-roll forming mechanism and an electric field-assisted micro-molding mechanism to first perform micro-roll forming on the material and then perform micro-molding to obtain a high-precision multi-level complex microstructure. A pulse power supply 1 is used to heat the material during the micro-roll forming and micro-molding process, improving the machinability of the material. A feeding mechanism 2 is used to transport the material into the roughing roll and the finishing roll for two roll forming processes, improving the accuracy of the basic structure on the material surface. Then, the unloading mechanism 3 delivers the rolled material. By setting the molding mechanism as a punch 4 and a blank groove 5, micro-molding can be performed on the basic structure on the material surface to form a multi-level complex microstructure.

[0051] like Figure 1 and Figure 2 As shown, further, in this embodiment, the roughing roll is composed of an upper roughing roll 6 and a lower roughing roll 7, and the finishing roll is composed of an upper finishing roll 8 and a lower finishing roll 9. The pulse power supply 1 is connected to the upper roughing roll 6 and the lower finishing roll 9 through a wire 13. A plurality of first structures 6-1 are formed on the rolling surface of the upper roughing roll 6, and a plurality of second structures 8-1 are formed on the rolling surface of the upper finishing roll 8.

[0052] In practical use, this embodiment, by setting up an upper roughing roll 6 and a lower roughing roll 7, as well as an upper finishing roll 8 and a lower finishing roll 9, enables the material to be rough rolled between the upper roughing roll 6 and the lower roughing roll 7, and fine rolled between the upper finishing roll 8 and the lower finishing roll 9. The pulse power supply 1 is connected to the upper roughing roll 6 and the lower finishing roll 9 through the wire 13. When the material passes between the roughing roll and the finishing roll and is in close contact with both rolls, an electrical circuit can be formed to heat the material. This facilitates the smooth processing of several basic structures on the material surface by the first structure 6-1 on the rolling surface of the upper roughing roll 6 and the second structure 8-1 on the rolling surface of the upper finishing roll 8. At the same time, in this embodiment, the positions of several first structures 6-1, second structures 8-1, and the microstructures at the bottom of the punch 4 are all matched.

[0053] It should be noted that in this embodiment, the upper coarse roller 6 and the lower fine roller 9 are insulated from the rest of the electric field-assisted micro roll forming mechanism, and the surfaces of the feeding mechanism 2 and the unloading mechanism 3 are made of insulating material; to ensure that the current circuit of the material, the upper coarse roller 6, the lower fine roller 9 and the pulse power supply 1 is insulated from the rest of the electric field-assisted micro roll forming mechanism.

[0054] like Figure 2 As shown, further, in this embodiment, the top of the punch 4 is connected to an upper insulating plate 4-1, the top of the upper insulating plate 4-1 is fixedly connected to an upper template 4-2, both sides of the upper template 4-2 are connected to guide posts 10 through guide sleeves 10-1, a punch 4-3 is provided on the upper template 4-2, and a pressure device is provided at the top of the punch 4-3; a pad 5-1 is fixedly connected to the bottom of the blank groove 5, a lower insulating plate 5-2 is fixedly connected to the bottom of the pad 5-1, a lower template 5-3 is fixedly connected to the bottom of the lower insulating plate 5-2, and the lower template 5-3 is connected to the lower end of the guide post 10 through guide sleeves 10-1; the pad 5-1 and the punch 4 are connected to the pulse power supply 1 through wires 13.

[0055] In actual use, in this embodiment, an insulating plate 4-1 is connected to the top of the punch 4, an upper template 4-2 is fixedly connected to the top of the upper insulating plate 4-1, and a punch 4-3 is set on the upper template 4-2, forming the punch 4, the upper insulating plate 4-1, and the upper template 4-2 into a whole. When the pressure device descends and contacts the punch 4-3, it drives the whole to move downward. The blank groove 5 is fixedly connected to the pad 5-1, the pad 5-1 is fixedly connected to the lower insulating plate 5-2, and the lower insulating plate 5-2 is fixed to the lower template 5-3. The connection is used to maintain structural stability; by using guide pillars 10 and guide sleeves 10-1 to connect the upper template 4-2 and the lower template 5-3, the punch 4 does not shift in the horizontal direction during the pressing process, which can ensure that the punch 4 and the blank groove 5 are properly aligned and avoid mispositioning, thereby ensuring the accuracy of multi-level complex microstructure forming; by connecting the pulse power supply 1 to the pad 5-1 and the punch 4 through the wire 13 to provide pulse current, the material is heated during the micro-molding process, improving the material's machinability.

[0056] It should be noted that in this embodiment, the punch 4 and the pad 5-1 are insulated from the rest of the electric field-assisted micro-molding mechanism to ensure that the current loop formed by the punch 4, the pad 5-1, the material and the pulse power supply 1 is insulated from the rest of the electric field-assisted micro-molding mechanism, so as to prevent the current from causing harm to personnel and the mechanism; at the same time, in this embodiment, the punch 4 and the upper insulating plate 4-1, and the pad 5-1 and the lower insulating plate 5-2 are connected by insulating bolts.

[0057] like Figure 2 and Figure 3As shown, in this embodiment, a limiting post 4-4 is arranged inside the punch 4, and the bottom of the limiting post 4-4 protrudes from the bottom surface of the punch 4.

[0058] In actual use, in this embodiment, a limiting post 4-4 is set in the punch 4 to prevent the punch 4 from being pressed down too much, which would cause abnormal deformation of the multi-level complex microstructure on the material surface.

[0059] It should be noted that in this embodiment, by changing the connection position of the wire 13, such as connecting the pulse power supply 1 to the upper coarse roller 6 and the lower coarse roller 7 through the wire 13, or connecting the pulse power supply 1 to both ends of the material through the wire 13, it is possible to achieve local heating of a specific area of ​​the material by changing the position of the current heating, thereby achieving shape control.

[0060] Example 2

[0061] The difference between this embodiment and Embodiment 1 is that: Figure 4 and Figure 5 As shown, in this embodiment, the first structure 6-1 is a quadrangular pyramid and the second structure 8-1 is a quadrangular frustum.

[0062] In practical use, in this embodiment, the first structure 6-1 is set as a square pyramid and the second structure 8-1 is set as a square frustum. The characteristic dimensions (length, width, height and edge length, etc.) of the square pyramid and the square frustum are all 0.01mm to 1mm. The longitudinal cross-sectional area of ​​the square pyramid is 70% to 90% of the longitudinal cross-sectional area of ​​the square frustum. By reducing the volume of the first structure 6-1, the deformation of the first structure 6-1 during roll forming is reduced, further reducing the deformation difficulty, and the concentrated stress / strain of the roll forming process is distributed to the two roll forming processes. At the same time, the base shape and size of the square pyramid and the square frustum are the same, which can reduce the forming difficulty of the second structure 8-1.

[0063] Furthermore, in this embodiment, the surface roughness of the second structure 8-1 is higher than that of the first structure 6-1.

[0064] In practical use, in this embodiment, the surface roughness of the second structure 8-1 is controlled to be higher than that of the first structure 6-1 to improve the accuracy of the material base structure; preferably, in this embodiment, the surface roughness Ra of the first structure 6-1 is 3.2 and the surface roughness Ra of the second structure 8-1 is 1.6.

[0065] Example 3

[0066] The difference between this embodiment and Embodiment 2 is that: Figure 6As shown, in this embodiment, multiple punches 4 are used to form multi-level complex microstructures. By dividing the multi-level complex microstructure into several levels of regions along the axial direction, and then including the previous level region in the next level region, several levels of punches 4 with the shape of the bottom microstructure being consistent with the shape of the above-mentioned several levels of regions are used to perform micro-molding in sequence. This allows the next level punch 4 to re-press the previous level region during molding, effectively improving the forming degree of the multi-level complex microstructure.

[0067] Preferably, in this embodiment, the surface roughness Ra of the microstructure at the punch 4 is set to 0.8, combined with the surface roughness Ra of the first structure 6-1 being 3.2 and the surface roughness Ra of the second structure 8-1 being 1.6, which can continuously reduce the roughness of the material surface microstructure during processing, thereby improving the accuracy of multi-level complex microstructures; at the same time, such as Figure 6 As shown, in this embodiment, the microstructure at the bottom of the punch 4 is a symmetrical trapezoidal shape. The height and step length of each layer of the trapezoidal shape are 5μm to 500μm, which reduces the scale of the multi-level complex microstructure after micro-molding, from the millimeter level to the micrometer level, and improves the capillary force of the multi-level complex microstructure.

[0068] The method for composite forming of large-area surface multi-level complex microstructures of the present invention is described in detail through Examples 4 to 7.

[0069] Example 4

[0070] In this embodiment, the blank 11 to be formed is a 1mm thick TA2 pure titanium plate, and the multi-level complex microstructure is divided into three levels along the axial direction. Then, the shape of the previous level region is included in the next level. The three-level punch 4 with the shape of the bottom microstructure is consistent with the shape of the three levels region is used for multiple micro molding. The punch 4 includes a first-level punch, a second-level punch and a third-level punch.

[0071] The forming method in this embodiment includes the following steps:

[0072] Step 1: After pre-processing the TA2 pure titanium plate with a slope at the front end, place it on the feeding mechanism 2. Adjust the roll gap of the roughing roll to 0.92mm and the roll gap of the finishing roll to 0.88mm. Start the feeding mechanism 2, the roughing roll and the finishing roll, and insert the front end of the TA2 pure titanium plate into the roughing roll and the finishing roll, ensuring that the roughing roll and the finishing roll are in close contact with the TA2 pure titanium plate at the same time to form an electrical circuit.

[0073] Step 2: Start the pulse power supply 1 to heat the TA2 pure titanium plate that formed the energized circuit in Step 1. After reaching 250°C, perform basic structure roll forming to obtain blank 12, and then turn off the pulse power supply 1. The pulse parameters of the pulse power supply 1 are: frequency 600Hz, current density 150A / mm². 2 ;

[0074] Step 3: After trimming the edges of the blank 12 obtained in Step 2, place it into the blank groove 5, and control the pressure device to move downward to drive the first-stage punch downward, so that the first-stage punch presses the blank 12.

[0075] Step 4: Restart pulse power supply 1 to heat the blank 12 pressed by the first-stage punch in step 3. After reaching 500℃, hold at that temperature for 3 minutes. Then, the first-stage punch continues to descend and apply force to the blank 12, causing the blank 12 to undergo its first molding deformation. Subsequently, the second-stage punch and the third-stage punch are replaced in sequence to perform molding deformation. After completion, turn off pulse power supply 1 and allow it to cool to obtain the part. The pulse parameters of pulse power supply 1 are: frequency 300Hz, current density 350A / mm². 2 .

[0076] Example 5

[0077] In this embodiment, the blank 11 to be formed is a 1.5mm thick GH4169 nickel-based high-temperature alloy plate. The multi-level complex microstructure is divided into four levels along the axial direction. Then, the shape of the previous level region is included in the next level. Multiple micro-molding is performed using a four-level punch 4 whose bottom microstructure shape is consistent with the shape of the four levels of regions. The punch 4 includes a first-level punch, a second-level punch, a third-level punch, and a fourth-level punch.

[0078] The forming method in this embodiment includes the following steps:

[0079] Step 1: After pre-processing the GH4169 nickel-based high-temperature alloy plate with a slope at the front end, place it on the feeding mechanism 2. Adjust the roll gap of the roughing roll to 1.2mm and the roll gap of the finishing roll to 1.1mm. Start the feeding mechanism 2, the roughing roll and the finishing roll, and insert the front end of the GH4169 nickel-based high-temperature alloy plate into the roughing roll and the finishing roll, ensuring that the roughing roll and the finishing roll are in close contact with the GH4169 nickel-based high-temperature alloy plate at the same time to form an electrical circuit.

[0080] Step 2: Start pulse power supply 1 to heat the GH4169 nickel-based high-temperature alloy plate that formed the energized circuit in Step 1. After reaching 230°C, perform basic structure roll forming to obtain blank 12, and then turn off pulse power supply 1. The pulse parameters of the pulse power supply 1 are: frequency 500Hz, current density 120A / mm². 2 ;

[0081] Step 3: After trimming the edges of the blank 12 obtained in Step 2, place it into the blank groove 5, and control the pressure device to move downward to drive the first-stage punch downward, so that the first-stage punch presses the blank 12.

[0082] Step 4: Restart the pulse power supply 1 to heat the blank 12 pressed by the first-stage punch in Step 3. After reaching 450℃, hold at that temperature for 5 minutes. Then, the first-stage punch continues to descend and apply force to the blank 12, causing the blank 12 to undergo its first molding deformation. Subsequently, the second-stage punch, third-stage punch, and fourth-stage punch are replaced in sequence to perform molding deformation. After completion, turn off the pulse power supply 1 and allow it to cool to obtain the part. The pulse parameters of the pulse power supply 1 are: frequency 220Hz, current density 290A / mm². 2 .

[0083] Example 6

[0084] The difference between this embodiment and Embodiment 4 is that: the blank 11 to be formed is a 3mm thick TA2 pure titanium plate; in step one, the roll gap of the roughing roll is 2.76mm, and the roll gap of the finishing roll is 2.42mm; in step two, the blank 11 to be formed is heated to 50℃, and the pulse parameters of the pulse power supply 1 are: frequency 2800Hz, current density 50A / mm². 2 In step four, the blank 12 is heated to 700℃ and held at that temperature for 2 minutes. The pulse parameters of the pulse power supply 1 are: frequency 100Hz, current density 480A / mm². 2 .

[0085] Example 7

[0086] The difference between this embodiment and Embodiment 5 is that: the blank 11 to be formed is a 0.8mm thick GH4169 nickel-based high-temperature alloy plate; in step one, the roll gap of the roughing roll is 0.64mm, and the roll gap of the finishing roll is 0.63mm; in step two, the blank 11 to be formed is heated to 400℃, and the pulse parameters of the pulse power supply 1 are: frequency 100Hz, current density 300A / mm². 2 In step four, the blank 12 is heated to 100℃ and held for 10 minutes. The pulse parameters of the pulse power supply 1 are: frequency 1000Hz, current density 60A / mm². 2 .

[0087] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Any simple modifications, alterations, or equivalent structural transformations made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for composite forming of large-area surface multi-level complex microstructures, characterized in that, The device includes an electric field-assisted micro roll forming mechanism and an electric field-assisted micro molding forming mechanism. The electric field-assisted micro roll forming mechanism includes a pulse power supply (1) and a feeding mechanism (2), a roughing roll, a finishing roll and a blanking mechanism (3) arranged sequentially along the conveying direction. The electric field-assisted micro molding forming mechanism includes a molding mechanism and a pressure device located above the molding mechanism. The molding mechanism includes a punch (4) and a blank groove (5) arranged below the punch (4). The bottom end of the punch (4) is provided with several microstructures. Step 1: After pre-processing the front end of the blank (11) to be formed with a slope, place it on the feeding mechanism (2), adjust the roll gap of the roughing roll and the finishing roll, start the feeding mechanism (2), the roughing roll and the finishing roll, and insert the front end of the blank (11) to be formed into the roughing roll and the finishing roll, ensuring that the roughing roll and the finishing roll are in close contact with the blank (11) to be formed at the same time to form an electrical circuit; the roll gap of the finishing roll is 1.01 to 1.15 times the roll gap of the roughing roll; Step 2: Use pulse power supply (1) to heat the blank (11) that has formed the power circuit in step 1. After reaching the roll forming temperature, roll forming of the basic structure is carried out to obtain the blank (12). Then turn off the pulse power supply (1). Step 3: After trimming the edges of the blank (12) obtained in Step 2, place it into the blank groove (5), and control the pressure device to move downward to drive the punch (4) to move downward, so that the punch (4) and the blank groove (5) press the blank (12) together. Step 4: Use pulse power supply (1) to heat the blank (12) pressed by punch (4) in step 3. After reaching the molding temperature, keep it warm. Then, punch (4) continues to move down to apply force to blank (12) so that blank (12) is subjected to graded molding deformation. After molding is completed, turn off pulse power supply (1) and wait for cooling to obtain part. The graded molding deformation is to divide the multi-level complex microstructure into several levels of regions. Multiple molding deformations are performed by changing the punch (4) with the corresponding microstructure at the bottom end. The molding area of ​​the next level punch includes the area of ​​the previous level, so as to re-press the microstructure formed by the previous level.

2. The method for composite forming of large-area surface multi-level complex microstructures according to claim 1, characterized in that, The roughing roll is composed of an upper roughing roll (6) and a lower roughing roll (7), and the finishing roll is composed of an upper finishing roll (8) and a lower finishing roll (9). The pulse power supply (1) is connected to the upper roughing roll (6) and the lower finishing roll (9) through a wire (13). Several first structures (6-1) are opened on the rolling surface of the upper roughing roll (6), and several second structures (8-1) are opened on the rolling surface of the upper finishing roll (8).

3. The method for composite forming of large-area surface multi-level complex microstructures according to claim 2, characterized in that, The surface roughness of the second structure (8-1) is higher than that of the first structure (6-1).

4. The method for composite forming of large-area surface multi-level complex microstructures according to claim 1, characterized in that, The top of the punch (4) is connected to an upper insulating plate (4-1), and the top of the upper insulating plate (4-1) is fixedly connected to an upper template (4-2). Both sides of the upper template (4-2) are connected to guide posts (10) through guide sleeves (10-1). A punch (4-3) is provided on the upper template (4-2), and a pressure device is provided at the top of the punch (4-3). The bottom of the blank groove (5) is fixedly connected to a pad (5-1), and the bottom of the pad (5-1) is fixedly connected to a lower insulating plate (5-2). The bottom of the lower insulating plate (5-2) is fixedly connected to a lower template (5-3), and the lower template (5-3) is connected to the lower end of the guide post (10) through guide sleeves (10-1). The pad (5-1) and the punch (4) are both connected to a pulse power supply (1) through wires (13).

5. The method for composite forming of large-area surface multi-level complex microstructures according to claim 1, characterized in that, The punch (4) is provided with a limiting post (4-4), and the bottom of the limiting post (4-4) protrudes from the bottom surface of the punch (4).

6. The method for composite forming of large-area surface multi-level complex microstructures according to claim 1, characterized in that, The material of the blank (11) to be formed in step one is one of magnesium and magnesium alloys, titanium and titanium alloys, nickel-based high-temperature alloys, refractory alloys, high-entropy alloys and steel.

7. The method for composite forming of large-area surface multi-level complex microstructures according to claim 1, characterized in that, The pulse parameters for heating by the pulse power supply (1) in step two are: frequency 100Hz~3000Hz, current density 50A / mm². 2 ~300A / mm 2 The roll forming temperature is 50℃~400℃.

8. The method for composite forming of large-area surface multi-level complex microstructures according to claim 1, characterized in that, The pulse parameters for heating by the pulse power supply (1) in step four are: frequency 100Hz~1000Hz, current density 50A / mm². 2 ~500A / mm 2 The molding temperature is 100℃~700℃, and the holding time is 2min~10min.

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