CN111633103A - An electro-hydraulic-electromagnetic composite forming system and forming method - Google Patents

Abstract

The invention discloses an electro-hydraulic-electromagnetic composite forming system, which belongs to the field of metal forming and manufacturing. in the middle; the first power module is connected to the metal and is used to discharge the metal wire to generate shock waves in the metal pipe; two booster coils are respectively arranged on the top and bottom ends of the metal pipe; the second power module is connected to the two booster coils They are both connected to discharge the two booster coils to generate booster electromagnetic force in the metal pipe fittings; the discharge control module is connected to both the two power supply modules and is used to control the discharge sequence of the two power supply modules, so that the shock wave and Under the synergistic effect of boosting electromagnetic force, the plastic deformation processing of metal pipe fittings is realized. The invention can effectively solve the problems of thinning and cracking of the workpiece caused by poor material fluidity in the prior electro-hydraulic forming technology, and improve the die attaching performance of the workpiece.

Description

An electro-hydraulic-electromagnetic composite forming system and forming method

technical field

The invention belongs to the field of metal forming and manufacturing, and more particularly, relates to an electro-hydraulic-electromagnetic composite forming system and a forming method.

Background technique

Lightweight aluminum alloy materials are widely used in automobile manufacturing, aerospace and other fields due to their superior mechanical properties. However, the effect of plastic processing of aluminum alloys using traditional processing technology is not ideal, which is mainly due to poor plasticity and difficult forming of aluminum alloys.

Studies have shown that high-rate forming can significantly improve the formability of materials. Electro-hydraulic forming is a manufacturing technology that uses shock waves generated by metal wire explosions to process workpieces. It belongs to high-speed forming and can greatly improve the forming performance of materials. However, in the process of electro-hydraulic forming, due to the insufficient fluidity of the material at the end of the workpiece, the workpiece is faced with problems such as thinning or even cracking. needs improvement.

SUMMARY OF THE INVENTION

Aiming at the defects and improvement needs of the prior art, the present invention provides an electro-hydraulic-electromagnetic composite forming system and a forming method, aiming at solving the thinning and cracking of the workpiece caused by poor material fluidity in the existing electro-hydraulic forming technology. problem, and improve the mold placement performance of the workpiece.

In order to achieve the above object, according to one aspect of the present invention, an electro-hydraulic-electromagnetic composite forming system is provided, comprising: a metal pipe to be formed, a die, a metal wire, a liquid medium, two booster coils, and a first power module , a second power supply module and a discharge control module;

The shape of the inner wall of the mold matches the shape to be formed; the metal pipe is placed in the mold, and both ends are sealed; the liquid medium is stored in the metal pipe;

The metal wire is immersed in the liquid medium and is connected to the first power module through two metal electrodes; the first power module is used to discharge the metal wire, so that the metal wire will gasify and explode and then generate plasma, which will generate shock waves on the metal pipe fittings ;

The two booster coils are respectively arranged at the top and bottom ends of the metal pipe fittings, and both are connected to the second power module; the second power module is used to discharge the two booster coils, so that the metal pipe fittings produce a booster in the same direction as the pipe fittings. Push the electromagnetic force to improve the fluidity of the material at the end of the metal pipe;

The discharge control module is connected with the first power supply module and the second power supply module, and the discharge control module is used to control the discharge sequence of the first power supply module and the second power supply module according to the shape to be formed, so as to achieve the synergistic effect of the shock wave and the boosting electromagnetic force Next, realize the plastic deformation processing of metal pipe fittings.

The invention utilizes the first power module to discharge the metal wire, generates a large pulse current in the metal wire, the temperature of the metal wire rises rapidly, gasification explosion occurs, and a violent chemical reaction occurs with the surrounding liquid medium to generate plasma. The expansion of the metal pipe will generate high-speed shock waves on the metal pipe to be formed; at the same time, the second power module is used to discharge the booster coil, and the booster coil generates an induced eddy current and a pulsed magnetic field at the end of the metal pipe, thereby causing the metal pipe to generate and Under the action of the boosting electromagnetic force in the same direction of the pipe fittings, the fluidity of the material at the end of the metal pipe to be formed is improved, which can effectively solve the problems of thinning and cracking of the workpiece; in the case of high-speed shock waves and boosting electromagnetic force Under the synergistic effect, the plastic deformation processing of the metal pipe to be formed is realized, and the forming performance is improved.

The present invention utilizes the first power module to discharge the wire to realize radial (workpiece center area) loading, utilizes the second power module to discharge the booster coil to realize axial (workpiece end area) loading, and the discharge control module The discharge sequence of the first power supply module and the second power supply module is controlled to achieve precise matching of axial and radial loading, which can effectively improve the mold-fitting performance of the workpiece.

Further, if the shape of the inner wall of the mold is symmetrical up and down, the second power supply module includes a set of power supplies, and the two booster coils are connected in series or in parallel with the power supply in the second power supply module;

If the shape of the inner wall of the mold is asymmetrical up and down, the second power module includes two sets of power sources, and each booster coil is respectively connected to one set of power sources.

When the shape of the inner wall of the mold (that is, the shape to be formed) is symmetrical up and down, the present invention connects two booster coils in series or in parallel to the same set of power supplies, thereby reducing the number of power supplies.

Further, the centers of the wire regions of the two booster coils are both located on the axis of the pipe wall of the metal pipe.

In the present invention, the centers of the wire areas of the two booster coils are located on the axis of the tube wall of the metal pipe fitting, and the material area of the metal pipe fitting is just between the wire areas of the two booster coils, thereby maximizing the The electromagnetic force provided by the booster coil to the metal pipe.

Further, the mold is provided with vent holes for balancing the inner and outer air pressure of the mold during the forming process.

Further, the first ends of the two metal electrodes are both inserted into the metal pipe and immersed in the liquid medium, and the metal wire is wound around the first ends of the two metal electrodes; the second ends of the two metal electrodes are both exposed, and the two metal electrodes are both exposed. The second ends of the metal electrodes are respectively connected to the positive and negative electrodes of the first power supply module.

Further, the booster coil arranged on the top end of the metal pipe is an air-core coil.

The invention utilizes the hollow coil as the boosting coil arranged on the top end of the metal pipe fitting, which can facilitate the insertion of the metal electrode into the metal pipe fitting.

According to another aspect of the present invention, there is provided a forming method based on the electro-hydraulic-electromagnetic composite forming system provided by the present invention, comprising:

Determine the discharge sequence of the first power module and the second power module according to the shape to be formed;

When the discharge sequence of the first power supply module arrives, a corresponding control signal is generated to make the power supply in the first power supply module discharge to the metal wire, so that the metal wire is gasified and exploded to generate plasma, and a shock wave is generated on the metal pipe fitting;

When the discharge sequence of the second power supply module arrives, a corresponding control signal is generated, so that the power supply in the second power supply module is discharged to the booster coil, so that a booster electromagnetic force consistent with the direction of the pipe fitting is generated in the metal pipe fitting, thereby improving the metal pipe fittings. The fluidity of the end material.

Further, the difference between the discharge sequence t ₀ of the first power supply module and the current peak time t _p of the booster coil |t ₀ -t _p |≤δ;

Among them, δ>0.

In the present invention, the discharge sequence of the first power supply module is set near the current peak time of the booster coil, which can ensure that the maximum booster electromagnetic force is utilized.

In general, through the above technical solutions conceived by the present invention, the following beneficial effects can be achieved:

(1) In the present invention, booster coils are respectively provided at both ends of the metal pipe fitting to be formed, and the booster coil is discharged through the second power module, so that a booster electromagnetic force consistent with the direction of the pipe fitting is generated in the metal pipe fitting, and the end of the metal pipe fitting is improved. The fluidity of the part material can effectively avoid the problem of thinning and cracking of the workpiece.

(2) The present invention uses the first power module to discharge the wire to realize radial loading, uses the second power module to discharge the booster coil to achieve axial loading, and uses the discharge control module to discharge the first power module and the second power supply. The discharge sequence of the module is controlled to achieve precise matching of axial and radial loading, which can effectively improve the mold-fitting performance of the workpiece.

Description of drawings

1 is a schematic structural diagram of an electro-hydraulic-electromagnetic composite forming device provided by an embodiment of the present invention;

2 is a schematic diagram of the induced eddy current and pulsed electromagnetic force generated by the booster coil at the end of the metal pipe to be formed according to an embodiment of the present invention;

3 is a schematic diagram of a discharge sequence of a first power supply module and a second power supply module according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of an early boosting electromagnetic force provided by an embodiment of the present invention;

5 is a schematic diagram of the action of boosting electromagnetic force and high-speed shock wave provided by an embodiment of the present invention;

Throughout the drawings, the same reference numbers are used to refer to the same elements or structures, wherein:

1 is the first power module, 2 is the metal electrode, 3 is the metal wire, 4 is the liquid medium, 5 is the booster coil, 6 is the second power module, 7 is the mold, 8 is the metal pipe fitting, 9 is the sealing ring, 10 For the discharge control module, 81 is the metal pipe fitting in the initial state, and 82 is the metal pipe fitting after processing.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

In the present invention, the terms "first", "second" and the like (if present) in the present invention and the accompanying drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

In order to solve the problems of workpiece thinning and cracking caused by poor material fluidity in the existing electro-hydraulic forming technology, and improve the mold-fitting performance of the workpiece, in one embodiment of the present invention, an electro-hydraulic-electromagnetic composite material is provided. The forming system, as shown in Figure 1, includes: a metal pipe to be formed 8, a die 7, a metal wire 3, a liquid medium 4, two booster coils 5, a first power supply module 1, a second power supply module 6 and a discharge control module 10;

The shape of the inner wall of the mold 7 matches the shape to be formed; the metal pipe fitting 8 is placed in the mold 7, and both ends are sealed by a sealing ring 9; the liquid medium 4 is stored in the metal pipe fitting 8;

The metal wire 3 is immersed in the liquid medium 4 and connected to the first power supply module 1 through two metal electrodes 2; the first power supply module 1 is used to discharge the metal wire 3, so that the metal wire 3 is gasified and exploded to generate plasma , a shock wave is generated on the metal pipe fitting 8;

The two booster coils 5 are respectively arranged at the top and bottom ends of the metal pipe fitting 8, and both are connected to the second power supply module; the second power supply module 6 is used to discharge the two booster coils 5, so that the The electromagnetic force in the same direction of the pipe fittings is boosted, as shown in Figure 2, thereby improving the fluidity of the material at the end of the metal pipe fitting 8 and promoting the flow of the material of the metal pipe fitting 8 into the cavity of the mold 7;

The discharge control module 10 is connected with the first power supply module 1 and the second power supply module 6, and the discharge control module is used to control the discharge sequence of the first power supply module 1 and the second power supply module 6 according to the shape to be formed, so as to prevent the shock wave and boost Under the synergistic effect of electromagnetic force, the plastic deformation processing of the metal pipe fitting 8 is realized.

In this embodiment, as shown in FIG. 2 , the shape of the inner wall of the mold 7, that is, the shape to be formed is symmetrical up and down, the second power module 6 includes a set of power supplies, and the two booster coils 5 can be connected in series or in parallel with each other. The power supplies in the second power supply module 6 are connected to each other, thereby reducing the number of power supplies; it should be noted that the description here is only a preferred embodiment of the present invention, and should not be construed as the only limitation of the present invention. In other embodiments of the invention, when the shape of the inner wall of the mold 7 is symmetrical up and down, two sets of power sources can also be used to separately supply power to the two booster coils;

In other embodiments of the present invention, if the mold 7 is relatively complex, for example, the shape of the inner wall of the mold 7 is asymmetrical up and down, the second power module 6 should include two sets of power sources, and each booster coil 5 is connected to one set of power sources respectively. connected to each other to supply power to each booster coil separately;

As shown in FIG. 1 , in this embodiment, both the first power supply module 1 and the second power supply module 6 include switching devices for turning on or off the power supply, and the discharge control module 10 controls the discharge sequence of each power supply module, It is realized by turning on and off the switching device; in other embodiments of the present invention, the discharge sequence of the power supply can also be controlled in other ways.

In this embodiment, the radius, winding direction and number of turns of the two booster coils 5 are the same; the specific radius and number of turns of the booster coil 5 should be determined according to the size of the pipe fitting;

In this embodiment, the centers of the wire areas of the two booster coils 5 are located on the axis of the tube wall of the metal tube 8. Correspondingly, the material area of the metal tube will be exactly between the wire areas of the two booster coils, such as As shown in FIG. 2 , the electromagnetic force provided by the booster coil to the metal pipe can thereby be maximized.

In the present embodiment, the mold 7 is also provided with an exhaust hole for balancing the internal and external air pressure of the mold 7 during the forming process;

Specifically, the air holes can be distributed equidistantly along the circumferential direction. Generally, 4 air holes are enough to discharge the air between the mold 7 and the metal pipe 8 during the forming process, so as to balance the internal and external air pressure of the mold 7; it should be noted that here It is only an exemplary description of the present invention, and should not be construed as the only limitation of the present invention. As long as the effect of balancing the internal and external air pressure of the mold 7 can be achieved, other ways of arranging air holes can also be applied to the present invention.

As shown in FIG. 1 , in this embodiment, the first ends of the two metal electrodes 2 are inserted into the metal pipe fitting 8 and immersed in the liquid medium 4, and the metal wire 3 is wound around the first ends of the two metal electrodes 2; The second ends of the two metal electrodes 2 are exposed to the outside, and the second ends of the two metal electrodes 2 are respectively connected to the positive and negative electrodes of the first power supply module 1; The hollow coil is used to facilitate the insertion of the metal electrode 2 into the metal pipe fitting 8 .

In practical applications, the electro-hydraulic-electromagnetic composite forming system shown in Figure 1 can be assembled according to the following steps:

(1) placing the metal pipe fitting 8 to be formed in the mold 7;

(2) Store the liquid medium 4 in the metal pipe fitting 8, and use two sealing rings 9 to seal the two ends of the metal pipe fitting 8 respectively;

(3) winding the metal wire 3 around one end of the two metal electrodes 2;

(4) inserting one end of the two metal electrodes 2 wound with the metal wire 3 into the metal pipe fitting 8;

(5) Place the two booster coils 5 on both ends of the metal pipe fitting 8 to be formed;

(6) Connect the first power module 1 to the metal electrode 2;

(7) connecting the second power supply module 6 to the booster coil;

(8) The discharge control module 10 is connected to the first power supply module 1 and the second power supply module 6 .

In another embodiment of the present invention, a forming method based on the above electro-hydraulic-electromagnetic composite forming system is provided, comprising:

Determine the discharge sequence of the first power supply module 1 and the second power supply module 6 according to the shape to be formed;

When the discharge sequence of the first power supply module 1 arrives, a corresponding control signal is generated, so that the power supply in the first power supply module 1 starts to discharge to the metal wire 3, so that the metal wire 3 is gasified and exploded to generate plasma, and the metal pipe A shock wave is generated on 8, so that the metal pipe fitting 8 is plastically deformed;

When the discharge sequence of the second power supply module 6 arrives, a corresponding control signal is generated, so that the power supply in the second power supply module 3 starts to discharge to the booster coil 5, so that the metal pipe fitting 8 generates a booster electromagnetic force consistent with the direction of the pipe fitting. , thereby improving the fluidity of the material at the end of the metal pipe fitting 8 .

In this implementation, the determined discharge sequence of the first power supply module 1 and the second power supply module 6 is shown in FIG. 3 , the discharge sequence t ₀ of the first power supply module is near the current peak time t _p of the booster coil 5 , Therefore, the maximum boosting electromagnetic force can be guaranteed to be utilized; in the actual control process, the difference |t ₀ between the discharge sequence t ₀ of the first power supply module 1 and the current peak time t _p of the booster coil 5 can be set. -t _p |≤δ(δ>0) to ensure that the discharge sequence t ₀ of the first power module is near the current peak time t _p of the booster coil 5;

In some other embodiments of the present invention, the discharge sequence of the first power supply module 1 may precede the discharge sequence of the second power supply module 6, and the first power supply module 1 and the second power supply module 6 may also be discharged at the same time; The flexible setting of the discharge sequence of the power supply module 1 realizes the flexible coordination of the high-speed shock wave and the boosting electromagnetic force, thereby realizing the effective regulation of the deformation behavior of the metal pipe fitting 8 to be formed.

According to the discharge sequence shown in FIG. 3 , when the metal pipe fitting 8 to be formed is plastically deformed by the forming method provided in the above embodiment, as shown in FIG. 4 , at time 0, the second power module 6 performs Discharge, induced eddy current and pulsed electromagnetic force are generated in the metal pipe fitting 81 in the initial state, and the pulsed electromagnetic force is preloaded on the end of the metal pipe fitting 8 (time 0 to t0); The discharge generates a large pulse current, which heats the metal wire 3, and the temperature of the metal wire 3 rises rapidly (time t0 to t1). , plasma is generated, and with the expansion of the gas, a high-speed shock wave is generated on the metal pipe to be formed; as shown in Figure 5, under the synergistic effect of the boosting electromagnetic force and the high-speed shock wave, the plastic deformation processing of the metal pipe 8 is realized, The processed metal pipe fitting 82 is obtained.

Those skilled in the art can easily understand that the above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention, etc., All should be included within the protection scope of the present invention.

Claims (8)

1. An electro-hydraulic-electromagnetic composite forming system, characterized in that it comprises: a metal pipe to be formed (8), a die (7), a metal wire (3), a liquid medium (4), two booster coils ( 5), a first power supply module (1), a second power supply module (6) and a discharge control module (10); The shape of the inner wall of the mold (7) matches the shape to be formed; the metal pipe (8) is placed in the mold (7), and both ends are sealed; the liquid medium (4) is stored in the In metal pipe fittings (8); The metal wire (3) is immersed in the liquid medium (4) and is connected to the first power supply module (1) through two metal electrodes (2); the first power supply module (1) is used for Discharging the metal wire (3), so that the metal wire (3) is gasified and exploded to generate plasma, and a shock wave is generated on the metal pipe fitting (8); Two booster coils (5) are respectively arranged at the top and bottom ends of the metal pipe fittings (8), and both are connected to the second power module; the second power module (6) is used for the two boosters. The push coil (5) is discharged, so that a boosting electromagnetic force consistent with the direction of the pipe is generated in the metal pipe (8), thereby improving the fluidity of the material at the end of the metal pipe (8); The discharge control module (10) is connected to the first power supply module (1) and the second power supply module (6), and the discharge control module is used for controlling the first power supply module ( 1) and the discharge sequence of the second power supply module (6), so as to realize the plastic deformation processing of the metal pipe fitting (8) under the synergistic effect of the shock wave and the boosting electromagnetic force. 2. The electro-hydraulic-electromagnetic composite forming system according to claim 1, characterized in that, if the shape of the inner wall of the mold (7) is symmetrical up and down, the second power module (6) includes a set of power supplies, and The two booster coils (5) are connected in series or in parallel with the power supply in the second power supply module (6); If the shape of the inner wall of the mold (7) is asymmetrical up and down, the second power supply module (6) includes two sets of power supplies, and each of the booster coils (5) is respectively connected to one set of power supplies. 3. The electro-hydraulic-electromagnetic composite forming system according to claim 1, characterized in that, the centers of the wire regions of the two booster coils 5 are both located on the axis of the pipe wall of the metal pipe (8). 4. The electro-hydraulic-electromagnetic composite forming system according to claim 1, characterized in that, said die (7) is provided with vent holes for balancing the inner and outer parts of said die (7) during the forming process. outside air pressure. 5. The electro-hydraulic-electromagnetic composite forming system according to claim 1, wherein the first ends of the two metal electrodes (2) are inserted into the metal pipe (8) and immersed in the liquid medium ( 4), the metal wire (3) is wound around the first ends of the two metal electrodes (2); the second ends of the two metal electrodes (2) are both exposed, and the second ends of the two metal electrodes (2) are exposed. The two ends are respectively connected to the positive and negative poles of the first power supply module (1). 6 . The electro-hydraulic-electromagnetic composite forming system according to claim 5 , wherein the booster coil ( 5 ) arranged on the top end of the metal pipe ( 8 ) is a hollow coil. 7 . 7. A forming method based on the electro-hydraulic-electromagnetic composite forming system according to any one of claims 1-6, characterized in that, comprising: Determine the discharge sequence of the first power supply module (1) and the second power supply module (6) according to the shape to be formed; When the discharge sequence of the first power supply module (1) arrives, a corresponding control signal is generated to make the power supply in the first power supply module (1) discharge to the wire (3), so that the wire (3) plasma is generated after gasification explosion, and shock wave is generated on the metal pipe fitting (8); When the discharge sequence of the second power supply module (6) arrives, a corresponding control signal is generated, so that the power supply in the second power supply module (3) is discharged to the booster coil (5), so that the metal pipe ( 8), a boosting electromagnetic force consistent with the direction of the pipe fitting is generated, thereby improving the fluidity of the material at the end of the metal pipe fitting (8). 8. The forming method according to claim 7, characterized in that, the difference between the discharge time sequence t ₀ of the first power supply module (1) and the current peak time t _p of the booster coil (5) |t ₀ -t _p |≤δ; Among them, δ>0.

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