Method and device for sintering metal-based powder activated by magnetic pulse-induced electric field

Abstract

The invention provides a magnetic pulse induced electric field activated metal-based powder sintering method and device, and belongs to the technical field of powder metallurgy. The device comprises a mold, an electromagnetic driving assembly and a current heating assembly which are coaxially arranged, a first pressing head and a second pressing head are coaxially arranged in the mold, and metal-based powder is placed between the first pressing head and the second pressing head; the current heating assembly is arranged around the metal-based powder and used for applying a direct-current electric field to the metal-based powder; the electromagnetic driving assembly is arranged on the side, away from the metal-based powder, of the first pressing head and used for driving the first pressing head to move towards the second pressing head to conduct high-speed pressing on the metal-based powder, and the electromagnetic driving assembly is matched with the current heating assembly to induce pulse discharging among metal-based powder particles under the direct-current electric field. The metal-based powder sintering method and device provided by the invention have two advantages of magnetic pulse high-speed pressing and electric field activation effect, and have the comprehensive characteristics of high speed, high pressure intensity, electric field activation, uniform density, high performance and the like.

Description

Technical Field

[0001] The invention relates to the technical field of powder metallurgy, and in particular to a method and a device for sintering metal-based powder activated by a magnetic pulse-induced electric field. Background Art

[0002] With the rapid development of MEMS towards miniaturization, integration and intelligence, higher requirements are placed on the manufacturing of high-performance micro parts. Powder metallurgy has the advantages of high material utilization, simple process and high forming precision, and is widely used in the manufacturing of micro parts. The use of multi-energy fields such as force, heat, electricity and magnetism can have extraordinary effects on the densification of powder materials and the regulation of organizational properties, thus realizing the precise forming and manufacturing of high-performance MEMS parts.

[0003] Electric field activated sintering uses an electric field formed by an applied pulse current to clean the surface impurities of metal-based powder particles, improve the diffusion capacity of the metal-based powder surface, and then uses a strong current to heat the metal powder for a short time under a relatively low pressure for sintering. This method has the advantages of cleaning and activating the surface of powder particles, but the electric field activated sintering forming process requires alternating discharges of pulse current and strong current, and the applied pressure is relatively low, which has certain limitations on improving the sintering rate and density.

[0004] Magnetic pulse pressing and sintering under heating conditions is a metal-based powder compaction and sintering method developed on the basis of magnetic pulse compaction. It combines the effects of temperature field and magnetic pulse pressure on metal-based powder, improves the plasticity of metal-based powder particles, and enables metal-based powder particles to be tightly combined. This method has the advantages of high speed and high pressure, but lacks the activation effect on metal-based powder, and the powder temperature rises by heat conduction from the mold inward, which is prone to uneven heating, slow heating, and density gradient defects in sintered parts. Therefore, the development of a sintering method that comprehensively utilizes electric field activation and magnetic pulse pressing and sintering is of great significance to solving the above-mentioned existing problems. Summary of the invention

[0005] In view of the technical problems existing in the background technology, the present invention provides a metal-based powder sintering method and device induced by magnetic pulse electric field activation, aiming to solve the technical problem that the existing electric field activation sintering and magnetic pulse pressing sintering methods have poor sintering effect on metal powder particles.

[0006] To solve the above technical problems, the first solution provided by the present invention is: a metal-based powder sintering device activated by magnetic pulse induced electric field, comprising: a coaxially arranged mold, an electromagnetic drive component and a current heating component; The mold has a hollow inner cavity, and a first pressing head and a second pressing head are coaxially arranged in the inner cavity, and the metal-based powder is placed between the first pressing head and the second pressing head; The current heating component is disposed around the metal-based powder and is used to apply a direct current electric field to the metal-based powder; The electromagnetic driving component is arranged on the side of the first pressing head away from the metal-based powder, and is used to drive the first pressing head to move toward the second pressing head to press the metal-based powder at high speed, and cooperate with the current heating component to induce pulse discharge between the metal-based powder particles under a DC electric field.

[0007] In the present invention, the pulse discharge induced in situ between the metal-based powder particles themselves will self-adjust and adapt according to their own impact and friction conditions. In places with high density, the impact and friction are not very serious, so the discharge is weaker. In places with low density, the discharge is stronger, making the overall density more uniform. The cooperation of the electromagnetic drive component and the current heating component can well meet the time synchronization of high-speed pressing and high-speed discharge.

[0008] Preferably, the mold further comprises a coaxially arranged base, a guide sleeve and a protective tube; the base is arranged around the second pressing head and is detachably connected to the second pressing head; one side of the guide sleeve is embedded in the protective tube, and the other side of the guide sleeve is detachably connected to the base; The current heating component includes an electrode, an electrode sheet and a DC circuit; the electrode is in circumferential contact with the metal-based powder, the electrode is vertically electrically connected to the electrode sheet, and the electrode sheet is electrically connected to the DC circuit, so as to provide a DC electric field to the metal-based powder.

[0009] Preferably, the base includes a substrate and two bosses, the substrate is vertically connected to the boss on one side close to the guide sleeve, the substrate is provided with a through hole for accommodating the second pressure head, and the two bosses are alternately arranged around the electrodes and cooperate to form the side wall of the accommodating cavity for the metal-based powder.

[0010] In an embodiment of the present invention, the electrode sheet is provided with an arc-shaped opening, the electrodes are stacked on the arc-shaped opening of the electrode sheet, placed in pairs on the base substrate, and cooperate with the two bosses of the base to form the side wall of the accommodating cavity for the metal-based powder; the electrode sheet is also provided with a circular hole, and the electrode sheet is connected to the DC circuit through the circular hole.

[0011] In an embodiment of the present invention, the base is annular, and the second pressure head is cylindrical and is installed in the through hole of the base by interference fit.

[0012] Preferably, the guide sleeve is provided with a first cavity and a second cavity which are coaxially connected along the direction from the first pressing head to the second pressing head; the first cavity is slidably connected to the end of the first pressing head away from the electromagnetic driving assembly, so as to control the axial movement of the first pressing head along the guide sleeve; the second cavity is provided with an electrode and a metal-based powder, and the inner diameter of the second cavity is larger than the inner diameter of the first cavity.

[0013] Preferably, an electrode sheet clearance groove is further provided on the end surface of the guide sleeve close to the base for fixing the electrode sheet.

[0014] In an embodiment of the present invention, the guide sleeve is further provided with a threaded hole, the base substrate is provided with a screw mounting hole, the threaded hole corresponds to the screw mounting hole, and the guide sleeve and the base are detachably connected by screws.

[0015] Preferably, the protective tube is provided with a third cavity, a fourth cavity and a fifth cavity which are coaxially connected in the direction from the first pressure head to the second pressure head; the electromagnetic drive assembly is installed and fixed in the third cavity, the fourth cavity is slidably connected to the end of the first pressure head close to the electromagnetic drive assembly, and the fifth cavity is nested and connected to the side of the guide sleeve away from the base; The inner diameter of the fourth cavity is smaller than the inner diameter of the third cavity, and smaller than the inner diameter of the fifth cavity.

[0016] Preferably, the electromagnetic drive assembly includes a discharge circuit, a coil, and a magnetic collector, an insulating sheet, and a drive plate coaxially arranged in sequence from the first pressure head to the second pressure head; the coil, the magnetic collector, and the insulating sheet are encapsulated in a protective tube by insulating materials; The coil is spirally coaxially wound around the outside of the magnetic collector, the discharge circuit is electrically connected to the coil, the discharge circuit discharges the coil, the coil generates an induced current in the magnetic collector, the electromagnetic force generated by the induced current acts on the drive plate, and the drive plate is used to drive the first pressing head to press the metal-based powder at high speed.

[0017] In an embodiment of the present invention, two parallel grooves are provided along the tangential direction of the third cavity of the protection tube to make room for the coil.

[0018] Preferably, the magnetic collector is a cylindrical structure with a slit on the side, and a first inner hole and a second inner hole are coaxially connected along the direction from the first pressure head to the second pressure head. The first inner hole is trumpet-shaped, and the second inner hole is a cylinder. The diameter of the first inner hole is larger than the diameter of the second inner hole. The magnetic collector is used to converge the magnetic field.

[0019] Preferably, the first pressure head is a three-section rotating body, which includes a disc body, a frustum and a cylinder fixedly connected in sequence along the direction from the first pressure head to the second pressure head; the diameter of the disc body is larger than the diameter of the cylinder; the first pressure head is used to transmit concentrated electromagnetic force section by section.

[0020] In order to solve the above technical problems, the second solution provided by the present invention is: a method for sintering metal-based powders activated by magnetic pulse induced electric field, using the above-mentioned metal-based powder sintering device activated by magnetic pulse induced electric field to sinter the metal-based powders, the method comprising the following steps: Placing a metal-based powder to be sintered in the mold, wherein the metal-based powder is located between the first pressing head and the second pressing head; The current heating component supplies direct current to the metal-based powder. At the same time, the electromagnetic driving component is energized to drive the first pressing head to move toward the second pressing head, thereby pressing the metal-based powder at a high speed to complete the electric field activated sintering of the metal-based powder induced by magnetic pulses.

[0021] In the present invention, the DC current density in the current heating component is 3000-30000A; the discharge voltage in the electromagnetic driving component is 2000-4000V, and the specific parameters can be determined according to the composition and state of the metal-based powder.

[0022] The principle of the technical solution of the present invention is: the present invention makes full use of the superposition effect of direct current electric field, high-speed magnetic pulse pressing, and pulse discharge between high-speed impact and friction-induced powder particles. Under the condition of a single direct current electric field, the gaps between metal-based powder particles form a capacitor, and the metal-based powder is driven by magnetic pulses to collide and rub at high speed, and the capacitance formed also changes, inducing pulse discharge between metal-based powder particles, thereby realizing the electric field activation effect of metal-based powder particles.

[0023] The reason why the present invention chooses a direct current field is that the direct current field has the advantages of uniform heating and constant current direction, which can prevent sintering defects such as excessive grain size. The pulse discharge induced in situ between the metal-based powder particles themselves has the advantages of self-adjustment and self-adaptation according to their own impact and friction conditions. The impact and friction are not very serious in places with high density, so the discharge is weaker; the discharge is stronger in places with low density, so that the overall density is more uniform. The high-speed induced pulse can well meet the time synchronization of high-speed pressing and high-speed discharge.

[0024] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a method and device for sintering metal-based powders by magnetic pulse-induced electric field activation. The metal-based powders can be sintered quickly and evenly by the coordinated arrangement of a mold, an electromagnetic drive component and an electric current heating component. Under a single DC electric field condition, the gaps between metal-based powder particles form a capacitor. The metal-based powders are driven by magnetic pulses to collide and rub at high speed, and the capacitance formed also changes, inducing pulse discharge between metal-based powder particles, thereby achieving surface cleaning and activation of metal-based powder particles. The metal-based powder sintering method and device provided by the present invention have the two major advantages of magnetic pulse high-speed pressing and electric field activation effect, and have the comprehensive characteristics of fast speed, high pressure, electric field activation, uniform density, high performance, etc. Compared with electric field activation sintering, multiple charging and discharging are not required, and circuit control is simplified. Compared with magnetic pulse pressing under heating conditions, on the basis of high pressing forming speed and high pressure, the electric field activation effect on metal-based powders is added, the temperature distribution is more uniform, and the heating speed is faster. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of an embodiment of a device for sintering metal-based powders by magnetic pulse induced electric field activation in the present invention; Figure 2It is a partial exploded view of an embodiment of a device for sintering metal-based powders by magnetic pulse induced electric field activation in the present invention; Figure 3 This is a macroscopic comparison diagram of the sintered samples of Example 1 of the present invention and Comparative Example 1; Figure 4 This is a comparison chart of the Vickers hardness of the sintered samples of Example 1 of the present invention and Comparative Example 1.

[0026] Explanation of the accompanying drawings: 1-mold, 2-electromagnetic drive component, 3-current heating component, 4-metal-based powder, 5-protective tube, 51-groove, 52-third cavity, 53-fourth cavity, 54-fifth cavity, 6-first pressure head, 61-disc, 62-table, 63-cylinder, 7-guide sleeve, 71-threaded hole, 72-electrode sheet give way groove, 73-first cavity, 74-second cavity, 8-second pressure head, 9-base, 91-substrate, 92-boss, 93-screw mounting hole, 94-through hole, 10-coil, 11-magnetic collector, 111-slit, 112-first inner hole, 113-second inner hole, 12-insulating sheet, 13-driving plate, 14-discharge circuit, 15-electrode sheet, 151-arc opening, 152-circular hole, 16-electrode, 17-DC circuit. DETAILED DESCRIPTION

[0027] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1 Please refer to Figure 1 and Figure 2 This embodiment provides a metal-based powder sintering device induced by magnetic pulse electric field activation, including: a coaxially arranged mold 1, an electromagnetic driving component 2 and an electric current heating component 3.

[0029] In this embodiment, the mold has a hollow inner cavity, and a first press head 6 and a second press head 8 are coaxially arranged in the inner cavity, and the metal-based powder 4 is placed between the first press head 6 and the second press head 8; the current heating component 3 is arranged at the lower part of the mold 1 around the metal-based powder, and the current heating component is used to apply a DC electric field to the metal-based powder 4; The electromagnetic drive component 2 is arranged on the upper part of the mold 1, and is used to drive the first pressing head 6 to move toward the second pressing head 8 to press the metal-based powder 4 at high speed, and cooperate with the current heating component 3 to induce pulse discharge between the particles of the metal-based powder 4 under a DC electric field, thereby realizing electric field activated sintering of the metal-based powder 4 particles.

[0030] The pulse discharge induced in situ between the particles of the metal-based powder 4 will self-adjust and adapt according to their own impact and friction conditions. In places with high density, the impact and friction are not very serious, so the discharge is weaker. In places with low density, the discharge is stronger, making the overall density more uniform. The cooperation between the electromagnetic drive component 2 and the current heating component 3 can well meet the time synchronization of high-speed pressing and high-speed discharge.

[0031] The specific structures of the various components of the magnetic pulse induced electric field activated metal-based powder sintering device and their relative positions are described in detail below.

[0032] The mold 1 includes a first pressing head 6, a second pressing head 8, a base 9, a guide sleeve 7 and a protective tube 5; the first pressing head 6 and the second pressing head 8 are arranged from top to bottom, and a metal-based powder 4 is placed between the first pressing head 6 and the second pressing head 8; the electromagnetic driving component 2 includes a coil 10, a magnetic collector 11, an insulating plate 12, a driving plate 13 and a discharge circuit 14; the current heating component 3 includes an electrode sheet 15, an electrode 16 and a DC circuit 17.

[0033] The first pressing head 6 is a three-section rotating body, the upper section is a disk 61, the middle section is a frustum 62, and the lower section is a cylinder 63; the diameter of the upper disk 61 of the first pressing head is larger than the diameter of the lower cylinder 63; the driving plate 13 is tightly attached to the upper end of the first pressing head 6; the electromagnetic force exerted on the driving plate 13 is transmitted and concentrated section by section through the upper section of the first pressing head 6, which greatly improves the energy utilization rate of the magnetic pulse pressing activation process of the metal-based powder 4.

[0034] The base 9 is annular and has a flat substrate 91 with a through hole 94 in the center. The second pressure head 8 is a cylinder and is installed in the through hole 94 of the base 9 by interference fit. Two bosses 92 are vertically arranged on the substrate 91, which cooperate with the second cavity 74 of the guide sleeve 7 to limit the electrode 16. Four screw mounting holes 93 are evenly distributed around the periphery, corresponding to the threaded holes 71 on the guide sleeve 7. The base 9 and the guide sleeve 7 are detachably connected by screws.

[0035] The guide sleeve 7 is a cylinder with two stepped cavities, and is provided with a first cavity 73 and a second cavity 74 which are through from top to bottom, and the inner diameter of the second cavity 74 is larger than the inner diameter of the first cavity 73; four threaded holes 71 are evenly distributed around the periphery of the guide sleeve 7 and correspond to the screw mounting holes 93 of the base 9, and the guide sleeve 7 and the base 9 are detachably connected by screws; an electrode sheet clearance groove 72 is provided on the bottom surface of the guide sleeve 7 for fixing the electrode sheet 15; the first cavity 73 of the guide sleeve 7 is slidably connected with the lower cylinder 63 of the first pressure head 6 to ensure the axial movement of the first pressure head along the guide sleeve 7; the second cavity 74 of the guide sleeve 7 cooperates with the two bosses 92 of the base 9 to limit the electrode 16, and the second cavity 74 accommodates the electrode and the metal-based powder.

[0036] The protective tube 5 is a cylinder with three stepped cavities, and is provided with a third cavity 52, a fourth cavity 53 and a fifth cavity 54 which are coaxially connected from top to bottom; the third cavity 52 of the protective tube provides installation and fixation for the electromagnetic drive component 2, and two parallel grooves 51 are opened along the tangent direction of the third cavity 52 to make room for the coil 10. The magnetic collector 11, the insulating sheet 12 and the coil 10 are encapsulated in the third cavity 52 of the protective tube 5 by insulating materials; the fourth cavity 53 of the protective tube provides a movable space for the first pressure head 6; the fifth cavity 54 of the protective tube is nested and connected with the upper end of the guide sleeve 7.

[0037] The current heating component 3 includes an electrode 16, an electrode sheet 15 and a DC circuit 17; the electrode 16 is in circumferential contact with the metal-based powder 4, and the electrode 16 is stacked on the arc-shaped opening 151 of the electrode sheet 15, and is placed in pairs on the base 9, and cooperates with the two bosses 92 of the base 9 to form the side wall of the accommodating cavity for the metal-based powder 4; the electrode sheet 15 is connected to the DC circuit 17 through the circular hole 152; the current heating component 3 is used to apply a DC electric field to the metal-based powder 4, and the current flows through the electrode sheet 15 and is amplified at the electrode 16, and the current directly passes through the metal-based powder 4.

[0038] The electromagnetic drive component 2 includes a discharge circuit 14 and a coaxially arranged coil 10, a magnetic collector 11, an insulating sheet 12 and a drive plate 13; the insulating sheet 12 is arranged at the bottom of the magnetic collector 11; the coil 10 is spirally wrapped around the outside of the magnetic collector 11, and the coil 10 is connected to the discharge circuit 14. The discharge circuit 14 discharges the coil 10, and the coil 10 generates an induced current in the magnetic collector 11. The magnetic collector 11 is a cylindrical structure with a slit 111 on the side, and is provided with a first inner hole 112 and a second inner hole 113 which pass through from top to bottom. The first inner hole 112 is trumpet-shaped, and the second inner hole 113 is cylindrical, and the bottom end diameter of the first inner hole 112 is larger than the diameter of the second inner hole 113; when the coil 10 is discharged through the discharge circuit 14, the induced current of the coil 10 in the magnetic collector 11 is mainly concentrated on the surface area of ​​the magnetic collector 11, and under the action of the slit 111, the induced current flows to the inner wall of the magnetic collector 11, thereby forming a loop to realize the current converging to the first inner hole 112 on the inner wall of the magnetic collector 11, realizing the concentration of the magnetic field at the end of the inner wall of the magnetic collector 11, so that the driving plate 13 obtains a greater electromagnetic force; the driving plate 13 is located below the insulating sheet and is close to the upper end of the first pressing head 6, and is used to drive the first pressing head 6 to press the metal-based powder 4 at high speed.

[0039] This embodiment also provides a method for sintering metal-based powders by magnetic pulse induced electric field activation, comprising the following steps: Step S1: embed the second press head 8 into the through hole 94 at the center of the base 9; put the electrode sheet 15 into the electrode sheet clearance groove 72, and the electrode 16 is symmetrically placed on the electrode sheet 15 corresponding to the two bosses 92 of the base 9; use four screws to fix the guide sleeve 7 on the base 9 through the screw mounting holes 93 and the threaded holes 71; put the metal-based powder 4 above the second press head 8; after the first press head 6 is installed from the first cavity 73 of the guide sleeve 7, the driving plate 13 is attached above the first press head 6; put the insulating sheet 12 into the third cavity 52 of the protective tube 5; surround the spiral coil 10 around the magnetic collector 11, put it into the third cavity 52 of the protective tube 5, and use insulating material to encapsulate it; embed the protective tube 5 on the guide sleeve 7; connect the discharge circuit 14 to the coil 10, and connect the DC circuit 17 to the electrode sheet 15; Step S2: the DC circuit 17 discharges the electrode sheet 15, and the DC current flows through the electrode 16 to reach the metal-based powder 4; the discharge circuit 14 discharges the coil 10 to generate electromagnetic force, and the driving plate 13 drives the first pressing head 6 to move downward under the drive of the electromagnetic force, and the metal-based powder 4 is pressed at a high speed; under the condition of a single DC electric field, a capacitor is formed between the particles of the metal-based powder 4, and the magnetic pulse generated by the electromagnetic driving component 2 drives the metal-based powder 4 to collide and rub at a high speed, and the capacitance formed is also changed, inducing pulse discharge between the particles of the metal-based powder 4, thereby realizing the electric field activated sintering of the particles of the metal-based powder 4; Step S3: disconnect the discharge circuit 14 and the DC circuit 17, open the protective tube 5, remove the first pressing head 6, and knock the second pressing head 8 from the bottom of the mold 1 to eject the sintered product.

[0040] In this embodiment, 5.32g of silver-based powder is used as the metal-based powder to be sintered, and the sintering conditions are as follows: the DC current in the current heating component is 22000A; the voltage of the discharge circuit in the electromagnetic drive component is 3500V. The density of the sample after sintering is measured to be 10.52g / cm 3 .

[0041] Comparative Example 1 This comparative example uses electric field activation to sinter 5.32g of silver-based powder, with a pressing force of 350MPa, a pulse current of 22000A, and a pulse interval of 10ms. The density of the sintered sample is measured to be 9.48g / cm 3 , Figure 3 This is a macroscopic comparison diagram of the sintered samples of this embodiment and comparative example 1. Vickers hardness measurements were performed at five equally spaced points along the diameter of the upper surface. Figure 4 It is a comparison chart of Vickers hardness between this embodiment and comparative example 1.

[0042] The results of Example 1 and Comparative Example 1 show that the Vickers hardness of the sample after sintering in the example of the present invention is more uniform and higher than that of Comparative Example 1. Generally, hardness is proportional to relative density. The test results show that the density uniformity of Example 1 is better than that of the Comparative Example.

[0043] The direct current electric field used in the magnetic pulse induced electric field activated metal-based powder sintering method provided by the present invention has the advantages of uniform heating and constant current direction. The pulse discharge induced in situ between the metal-based powder particles themselves has the advantages of self-adjustment and self-adaptation according to their own impact and friction conditions. In places with very high density, the impact and friction are not very serious, so the discharge is weaker; in places with low density, the discharge is stronger, so that the overall density is more uniform. In addition, the high-speed induced pulse can well meet the time synchronization of high-speed pressing and high-speed discharge. The present invention makes full use of the superposition effect of the direct current electric field, magnetic pulse high-speed pressing, and high-speed impact and friction-induced pulse discharge between powder particles, thereby improving the uniformity of sintering density.

[0044] It should be noted that the present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present invention are all included in the technical scope of the present invention. In addition, without departing from the scope of the main purpose of the present invention, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present invention.

Claims

1. A metal-based powder sintering device activated by magnetic pulse induced electric field, characterized in that: include: A coaxially arranged mold, an electromagnetic drive assembly, and an electric current heating assembly; The mold has a hollow inner cavity, and a first pressing head and a second pressing head are coaxially arranged in the inner cavity, and the metal-based powder is placed between the first pressing head and the second pressing head; The current heating component is disposed around the metal-based powder and is used to apply a direct current electric field to the metal-based powder; The electromagnetic driving component is arranged on the side of the first pressing head away from the metal-based powder, and is used to drive the first pressing head to move toward the second pressing head to press the metal-based powder at high speed, and cooperate with the current heating component to induce pulse discharge between metal-based powder particles under a DC electric field.

2. The metal-based powder sintering device induced by magnetic pulse electric field activation according to claim 1, characterized in that: The mold further comprises a coaxially arranged base, a guide sleeve and a protective tube; the base is arranged around the second pressing head and is detachably connected to the second pressing head; one side of the guide sleeve is embedded in the protective tube, and the other side of the guide sleeve is detachably connected to the base; The current heating component includes an electrode, an electrode sheet and a DC circuit; the electrode is in circumferential contact with the metal-based powder, the electrode is vertically electrically connected to the electrode sheet, and the electrode sheet is electrically connected to the DC circuit to provide a DC electric field to the metal-based powder.

3. The metal-based powder sintering device induced by magnetic pulse electric field activation according to claim 2, characterized in that: The base includes a substrate and two bosses, wherein the substrate is vertically connected to the boss on one side close to the guide sleeve, and the substrate is provided with a through hole for accommodating the second pressure head. The two bosses are alternately arranged around the electrodes and cooperate to form the side wall of the accommodating cavity for the metal-based powder.

4. The metal-based powder sintering device induced by magnetic pulse electric field activation according to claim 2, characterized in that: The guide sleeve is provided with a first cavity and a second cavity which are coaxially connected along the direction from the first pressing head to the second pressing head; the first cavity is slidably connected to the end of the first pressing head away from the electromagnetic driving assembly, so as to control the axial movement of the first pressing head along the guide sleeve; the electrode and the metal-based powder are arranged in the second cavity, and the inner diameter of the second cavity is larger than the inner diameter of the first cavity.

5. The metal-based powder sintering device induced by magnetic pulse electric field activation according to claim 4, characterized in that: An electrode sheet paving groove is also provided on the end surface of the guide sleeve close to the base for fixing the electrode sheet.

6. The device for sintering metal-based powders by magnetic pulse induced electric field activation according to claim 2, characterized in that: The protective tube is provided with a third cavity, a fourth cavity and a fifth cavity which are coaxially connected in the direction from the first pressure head to the second pressure head; the electromagnetic drive assembly is installed and fixed to the third cavity, the fourth cavity is slidably connected to the end of the first pressure head close to the electromagnetic drive assembly, and the fifth cavity is nested and connected to the side of the guide sleeve away from the base; The inner diameter of the fourth cavity is smaller than the inner diameter of the third cavity, and smaller than the inner diameter of the fifth cavity.

7. The device for sintering metal-based powders by magnetic pulse induced electric field activation according to claim 2, characterized in that: The electromagnetic drive assembly comprises a discharge circuit, a coil, and a magnetic collector, an insulating sheet, and a drive plate coaxially arranged in sequence along the direction from the first pressure head to the second pressure head; the coil, the magnetic collector, and the insulating sheet are encapsulated in the protective tube by insulating materials; The coil is spirally coaxially wound around the outside of the magnetic collector, and the discharge circuit is electrically connected to the coil. The discharge circuit discharges the coil, and the coil generates an induced current in the magnetic collector. The electromagnetic force generated by the induced current acts on the drive plate, and the drive plate is used to drive the first pressing head to press the metal-based powder.

8. The device for sintering metal-based powders by magnetic pulse induced electric field activation according to claim 7, characterized in that: The magnetic collector is a cylindrical structure with a slit on the side, and a first inner hole and a second inner hole are coaxially connected along the direction from the first pressure head to the second pressure head. The first inner hole is trumpet-shaped, the second inner hole is cylindrical, and the diameter of the first inner hole is larger than the diameter of the second inner hole.

9. The device for sintering metal-based powders by magnetic pulse induced electric field activation according to claim 2, characterized in that: The first pressing head is a three-section rotating body, which includes a disc body, a frustum and a cylinder that are fixedly connected in sequence along the direction from the first pressing head to the second pressing head; the diameter of the disc body is larger than the diameter of the cylinder.

10. A method for sintering metal-based powders by magnetic pulse induced electric field activation, using the metal-based powder sintering device by magnetic pulse induced electric field activation as claimed in any one of claims 1 to 9, characterized in that: The method comprises the following steps: Placing a metal-based powder to be sintered in the mold, wherein the metal-based powder is located between the first pressing head and the second pressing head; The current heating component supplies direct current to the metal-based powder. At the same time, the electromagnetic driving component is energized to drive the first pressing head to move toward the second pressing head, thereby pressing the metal-based powder at a high speed to complete the electric field activated sintering of the metal-based powder induced by magnetic pulses.

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