Vibration-assisted electromagnetic forming device and method based on driving plate

Abstract

The invention discloses a vibration-assisted electromagnetic forming device and method based on a drive board, and the device comprises a background magnetic field module which provides a background magnetic field for a workpiece; the vibration auxiliary module comprises an alternating current discharge loop and provides alternating current with specific frequency and amplitude for the workpiece, and the workpiece can generate high-frequency vibration under the action of the background magnetic field and the alternating current; a non-conductive isolation piece is arranged between the driving plate and the workpiece, the electromagnetic driving module provides pulse large current for the driving plate so as to generate pulse electromagnetic force, and the driving plate acts on the workpiece to enable the workpiece to deform. High-frequency vibration and electromagnetic forming act on the formed workpiece and the driving plate correspondingly, mutual influence between the vibration auxiliary loop and the electromagnetic driving loop is avoided, the requirements for a power source and a switch of the vibration auxiliary loop are lowered, and workpiece forming is better achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic forming, and in particular to a vibration-assisted electromagnetic forming device and method based on a driving plate. Background Art

[0002] As a cutting-edge method to break through the bottleneck of metal material processing, electromagnetic forming technology has shown significant advantages in the forming and manufacturing of lightweight alloys (aluminum, magnesium, titanium, etc.) with its non-contact and high-speed characteristics, especially in the fields of lightweight automobiles and complex aviation structural parts processing. At present, when traditional electromagnetic forming technology is used to process low-conductivity and high-strength metals, it is limited by the intrinsic characteristics of the material, and the induced eddy current intensity of the workpiece is insufficient, resulting in the driving Lorentz force being difficult to meet the requirements of plastic deformation. Vibration-assisted electromagnetic forming technology can greatly improve the forming limit and forming quality of the material by applying high-frequency vibration, effectively solving problems such as difficult deformation and unsatisfactory forming depth.

[0003] However, in current vibration-assisted electromagnetic forming devices, the alternating current required for vibration assistance and the pulsed high current required for electromagnetic forming both adopt the method of directly discharging to the workpiece. The vibration-assisted circuit and the electromagnetic forming circuit are connected in parallel at both ends of the workpiece. The interaction between the two circuits is inevitable, which puts high requirements on the vibration-assisted power supply and its switching device, limits the control range of the vibration parameters, and affects the workpiece forming to a certain extent. Summary of the Invention

[0004] In view of the shortcomings of the background technology, the object of the present invention is to provide a vibration-assisted electromagnetic forming device and method based on a driving plate.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A vibration-assisted electromagnetic forming device based on a driving plate, comprising:

[0007] A background magnetic field module, which provides a background magnetic field for the workpiece;

[0008] A vibration auxiliary module includes an AC discharge circuit that provides AC current of a specific frequency and amplitude to the workpiece. Under the action of the background magnetic field and the AC current, the workpiece can generate high-frequency vibrations;

[0009] An electromagnetic driving module and a driving plate, wherein a non-conductive isolator is provided between the driving plate and the workpiece, and the electromagnetic driving module provides a pulsed large current to the driving plate to generate a pulsed electromagnetic force, and the driving plate then acts on the workpiece to cause it to deform.

[0010] Furthermore, the non-conductive isolation piece is a non-conductive soft pad.

[0011] Furthermore, the background magnetic field module includes a capacitor group C1 discharge circuit and a background magnetic field coil. The capacitor group C1 discharge circuit is used to apply a pulsed large current with specific parameters to the background magnetic field coil. The background magnetic field coil is used to generate a uniform spatial background electromagnetic field in the forming area.

[0012] Furthermore, the electromagnetic driving module includes a capacitor group C2 discharge circuit for applying a pulsed high current to the driving board.

[0013] Furthermore, the driving plate is a metal driving plate.

[0014] Furthermore, the metal driving plate is made of any one of pure copper, aluminum, silver, magnesium, zinc and / or tin.

[0015] An electromagnetic forming method based on the vibration-assisted electromagnetic forming device based on the driving plate as described in any one of the above items comprises the following steps:

[0016] S1: Close switch K1, turn on the discharge circuit of capacitor group C1, apply a pulsed high current to the background magnetic field coil, and generate a strong magnetic field required for forming in the forming area;

[0017] S2: Close switch K2, conduct the AC discharge circuit, and the workpiece generates high-frequency vibration under the action of the electromagnetic field and AC current;

[0018] S3: Close the switch K3, conduct the discharge circuit of the capacitor group C2, and the driving plate generates electromagnetic force under the electromagnetic field and the pulsed large current. The driving plate then acts on the workpiece to cause it to bulge freely.

[0019] Furthermore, in S3, the driving plate acts on the workpiece through a non-conductive isolation member.

[0020] Furthermore, before S1, the following steps are required: S11: determining the frequency and amplitude of the AC discharge circuit according to the material, thickness, size and forming target of the workpiece to be formed; S12: optimizing the discharge voltage and discharge circuit resistance parameters of the energy storage capacitors in the discharge circuits of capacitor group C1 and capacitor group C2 by simulation under the action of existing ultrasonic vibration parameters; S13: setting the selected AC discharge parameters and pulse discharge parameters.

[0021] The beneficial effects of the present invention are:

[0022] 1. The present invention proposes a vibration-assisted electromagnetic forming device based on a drive plate, comprising a background magnetic field module that provides a background magnetic field for the workpiece; a vibration-assisted module that includes an AC discharge circuit that provides AC current of a specific frequency and amplitude to the workpiece. Under the action of the background magnetic field and the AC current, the workpiece can generate high-frequency vibrations; an electromagnetic drive module and a drive plate. The electromagnetic drive module provides a large pulsed current to the drive plate to generate a pulsed electromagnetic force, which in turn acts on the workpiece to deform it. The present invention applies high-frequency vibration and electromagnetic forming to the formed workpiece and the drive plate respectively, avoiding the mutual influence between the vibration-assisted circuit and the electromagnetic drive circuit, reducing the requirements for the power supply and switch of the vibration-assisted circuit, and thus ensuring that the control range of the vibration parameters is not limited, thereby better achieving workpiece forming.

[0023] 2. The present invention proposes a vibration-assisted electromagnetic forming device based on a driving plate, in which a non-conductive isolator is provided between the driving plate and the workpiece. The setting of the non-conductive isolator electrically isolates the driving plate from the workpiece, and at the same time makes the force on the workpiece more uniform, enhances the vibration transmission effect, reduces the wear of the workpiece, and increases the service life of the equipment.

[0024] 3. The electromagnetic forming method proposed in this invention uses a background magnetic field module to provide a strong magnetic field to the forming device, ensuring the presence of the required strong magnetic field in the workpiece's forming area. Alternating current is then passed through the workpiece to be formed, causing it to vibrate at high frequencies under the influence of the background magnetic field. This high-frequency vibration effectively reduces the material's resistance to deformation and the forming force required for subsequent workpieces. Discharge is then applied to a driver plate via a capacitor bank. The strong magnetic field and high pulsed current generate a strong electromagnetic force on the driver plate, which acts on the workpiece through a non-conductive isolator, causing it to bulge freely. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 This is an overall schematic diagram of a vibration-assisted electromagnetic forming device based on a driving plate of the present invention.

[0027] Figure 2 This is a schematic diagram of a discharge circuit of a vibration-assisted electromagnetic forming device based on a driving plate of the present invention.

[0028] In the figure, 10, background magnetic field coil; 20, forming die; 30, workpiece; 40, driving plate; 50, edge holding device; 60, non-conductive soft pad. DETAILED DESCRIPTION

[0029] The following combination Figure 1-2 The present invention will be described in detail.

[0030] A vibration-assisted electromagnetic forming device based on a driving plate, comprising:

[0031] A background magnetic field module, which provides a background magnetic field for the workpiece 30;

[0032] A vibration auxiliary module includes an AC discharge circuit that provides AC power of a specific frequency and amplitude to the workpiece 30. Under the action of the background magnetic field and the AC power, the workpiece 30 can generate high-frequency vibrations;

[0033] The electromagnetic driving module and the driving plate 40 are provided with a non-conductive isolation piece between the driving plate 40 and the workpiece 30. The electromagnetic driving module provides a large pulse current to the driving plate 40 to generate a pulse electromagnetic force, and the driving plate 40 then acts on the workpiece 30 to deform it.

[0034] Specifically, compared to the method of using high-frequency vibration and electromagnetic forming modules to directly discharge the workpiece 30, the present invention uses high-frequency vibration and electromagnetic forming to act on the formed workpiece 30 and the drive plate 40 respectively. The workpiece 30 and the drive plate 40 are electrically isolated by a non-conductive soft pad 60, avoiding the mutual influence between the vibration auxiliary circuit and the electromagnetic drive circuit, reducing the requirements for the power supply and switch of the vibration auxiliary circuit, and ensuring that the control range of the vibration parameters is not limited. The high-frequency vibration module and the electromagnetic forming module are debugged independently to improve the reliability of the system. Therefore, the dual-module form can significantly improve the forming quality, increase the energy transfer efficiency and reduce the maintenance cost, and better realize the forming of the workpiece 30.

[0035] The present invention introduces high-frequency vibration into electromagnetic drive technology. Vibration of a certain intensity can alter microscopic mechanisms such as dislocation motion and atomic diffusion within the material, reducing the material's resistance to deformation and improving its plasticity and fluidity, thereby helping to reduce the forming force required to form the workpiece 30 during the subsequent electromagnetic drive phase. The AC discharge circuit in the vibration-assisted module delivers AC current of appropriate frequency and magnitude to the workpiece 30 after rectification, filtering, and inversion. In actual devices, the wires in the AC discharge circuit are kept as short as possible to prevent the strong pulsed magnetic field from significantly affecting the AC power supply and improve the reliability of the power supply system.

[0036] The electromagnetic force provided by the drive plate 40 deforms the workpiece 30. The current within the high-conductivity, low-strength drive plate 40 remains high, making it easier to generate the electromagnetic force required for forming, significantly reducing the difficulty of forming the low-conductivity, high-strength workpiece 30. The drive plate 40 is constructed of a high-conductivity, low-strength material. The interaction between the high pulse current and the background magnetic field produces a strong and relatively uniform pulsed electromagnetic force. The direction of the current within the drive plate 40 aligns with and remains constant in the magnetic field, ensuring that the force acting on the drive plate 40 is correct and consistent.

[0037] To avoid frequent reversing of current, a freewheeling circuit consisting of a diode and a freewheeling impedance is connected in parallel at both ends of the capacitor; when the freewheeling branch is turned on, the reverse electric energy is quickly consumed in the freewheeling branch, reducing the temperature rise of the driving board 40, thereby improving the safety and effectiveness of the circuit.

[0038] like Figure 1 As shown, the entire forming device is placed at the center of the background magnetic field coil 10, also known as the forming coil, subjecting the forming area of ​​the workpiece 30 to a uniform, strong magnetic field. The workpiece 30 to be formed is placed horizontally above the forming die 20, with the drive plate 40 positioned above it. A clamping device 50 secures the workpiece 30 and the drive plate 40 to prevent horizontal displacement during the forming process. Discharge circuit wires are connected to both ends of the drive plate 40 and the workpiece 30, respectively, for discharging the capacitor bank and the AC power supply.

[0039] In this embodiment, the non-conductive isolating member is a non-conductive soft pad 60. Specifically, compared with a hard non-conductive isolating member, the non-conductive soft pad 60 can make the workpiece bear the force more evenly and reduce the wear of the workpiece.

[0040] In this embodiment, the background magnetic field module includes a capacitor group C1 discharge circuit and a background magnetic field coil 10. The capacitor group C1 discharge circuit is used to apply a pulsed large current with specific parameters to the background magnetic field coil 10. The background magnetic field coil 10 is used to generate a uniform spatial background electromagnetic field in the forming area.

[0041] In this embodiment, the electromagnetic driving module includes a capacitor bank C2 discharge circuit for applying a pulsed high current to the driving board 40. Specifically, the current can be directly controlled by the discharge capacitor bank.

[0042] In this embodiment, the driving plate 40 is a metal driving plate 40 .

[0043] In this embodiment, the metal driving plate 40 is made of any one of pure copper, aluminum, silver, magnesium, zinc, and tin.

[0044] An electromagnetic forming method based on any of the aforementioned vibration-assisted electromagnetic forming devices based on a driving plate, comprising the following steps:

[0045] S1: Close the switch K1, turn on the discharge circuit of the capacitor group C1, apply a pulsed high current to the background magnetic field coil 10, and generate a strong magnetic field required for forming in the forming area;

[0046] S2: Close the switch K2 to conduct the AC discharge circuit. The workpiece 30 generates high-frequency vibration under the action of the electromagnetic field and the AC current.

[0047] S3: Close the switch K3, conduct the discharge circuit of the capacitor group C2, and the driving plate 40 generates electromagnetic force under the electromagnetic field and the pulsed large current. The driving plate 40 then acts on the workpiece 30 to cause it to bulge freely.

[0048] In this embodiment, in S3 , the driving plate 40 acts on the workpiece 30 through the non-conductive isolation member.

[0049] In this embodiment, the following steps are required before S1: S11: determining the frequency and amplitude of the AC discharge circuit based on the material, thickness, size and forming target of the workpiece 30 to be formed; S12: optimizing the discharge voltage and discharge circuit resistance parameters of the energy storage capacitors in the discharge circuits of the capacitor group C1 and the capacitor group C2 by simulation under the action of the existing ultrasonic vibration parameters; S13: setting the selected AC discharge parameters and pulse discharge parameters.

[0050] Specifically, such as Figure 2 As shown, the discharge circuit of the capacitor group C1 discharges to the background magnetic field coil 10, and the circuit is protected by a series inductor; when the switch K2 is closed, the AC power supply in the AC discharge circuit directly provides AC power with adjustable frequency and current to the workpiece 30 through the rectifier, capacitor filtering and inverter; when the switch K3 is closed, the discharge circuit of the capacitor group C2 is connected to the drive board 40, and a pulsed large current with specific parameters is applied to the drive board 40. The generated electromagnetic force acts on the workpiece 30 through the soft pad, causing it to bulge freely; to avoid frequent reversing of the current, a freewheeling circuit composed of a diode and a freewheeling resistor is connected in parallel at both ends of the capacitor to improve the safety of the circuit.

[0051] In the actual device setting, considering the influence of the pulsed strong magnetic field on the AC power supply, the background magnetic field coil 10 should be kept at a certain safe distance from the AC power supply as much as possible, and the wire of the AC discharge circuit should be as short as possible.

[0052] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand and implement the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A vibration-assisted electromagnetic forming device based on a driving plate, characterized in that: include: A background magnetic field module, which provides a background magnetic field for the workpiece; A vibration auxiliary module includes an AC discharge circuit that provides AC current of a specific frequency and amplitude to the workpiece. Under the action of the background magnetic field and the AC current, the workpiece can generate high-frequency vibrations; An electromagnetic driving module and a driving plate, wherein a non-conductive isolator is provided between the driving plate and the workpiece, and the electromagnetic driving module provides a pulsed large current to the driving plate to generate a pulsed electromagnetic force, and the driving plate then acts on the workpiece to cause it to deform.

2. A vibration-assisted electromagnetic forming device based on a driving plate according to claim 1, characterized in that: The non-conductive isolating member is a non-conductive soft pad.

3. A vibration-assisted electromagnetic forming device based on a driving plate according to claim 1 or 2, characterized in that: The background magnetic field module includes a capacitor group C1 discharge circuit and a background magnetic field coil. The capacitor group C1 discharge circuit is used to apply a pulsed large current with specific parameters to the background magnetic field coil. The background magnetic field coil is used to generate a uniform spatial background electromagnetic field in the forming area.

4. A vibration-assisted electromagnetic forming device based on a driving plate according to claim 3, characterized in that: The electromagnetic driving module includes a capacitor group C2 discharge circuit for applying a pulsed high current to the driving board.

5. The vibration-assisted electromagnetic forming device based on a driving plate according to claim 4, characterized in that: The driving plate is a metal driving plate.

6. The vibration-assisted electromagnetic forming device based on a driving plate according to claim 5, characterized in that: The metal driving plate is made of any one of pure copper, aluminum, silver, magnesium, zinc and tin.

7. An electromagnetic forming method based on the vibration-assisted electromagnetic forming device based on the driving plate according to any one of claims 1 to 6, characterized in that: The steps include: S1: Close switch K1, turn on the discharge circuit of capacitor group C1, apply a pulsed high current to the background magnetic field coil, and generate a strong magnetic field required for forming in the forming area; S2: Close switch K2, conduct the AC discharge circuit, and the workpiece generates high-frequency vibration under the action of the electromagnetic field and AC current; S3: Close the switch K3, conduct the discharge circuit of the capacitor group C2, and the driving plate generates electromagnetic force under the electromagnetic field and the pulsed large current. The driving plate then acts on the workpiece to cause it to bulge freely.

8. The electromagnetic forming method according to claim 7, wherein: In S3, the driving plate acts on the workpiece through a non-conductive isolation member.

9. An electromagnetic forming method according to claim 7 or 8, characterized in that: Before S1, the following steps are required: S11: determining the frequency and amplitude of the AC discharge circuit based on the material, thickness, size and forming target of the workpiece to be formed; S12: optimizing the discharge voltage and discharge circuit resistance parameters of the energy storage capacitors in the discharge circuits of capacitor group C1 and capacitor group C2 through simulation under the action of existing ultrasonic vibration parameters; S13: setting the selected AC discharge parameters and pulse discharge parameters.

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