Device for assisting high-speed impact connection through pulse current and method and application thereof

Abstract

The invention relates to the technical field of high-speed impact connection, in particular to a pulse current assisted high-speed impact connection device and method and application thereof. The device comprises a high-energy field driver, an insulating plate and a pulse current plasticizing capacitor. The method comprises the following steps: separating two to-be-connected alloy plates through an insulating plate, and respectively connecting the two to-be-connected alloy plates to two ends of a pulse current plasticizing capacitor; during working, the high-energy field driver instantaneously drives the flying plate to impact the substrate at a high speed; at the moment that the flying plate is about to be in contact with the substrate, electric arc is generated between the two alloy plates to preheat a connecting area; when the flying plate is in contact with the substrate, the pulse current plasticizing capacitor forms a closed loop and rapidly discharges; and the interface temperature is sharply increased by the pulse current, and high-speed crack-free connection between the alloy plates is realized by combining the coupling effect of instantaneous high voltage, high temperature and strong current. According to the method, the bottleneck problem that a traditional high-speed impact connection technology is difficult to apply to brittle and hard materials is solved by cooperatively regulating and controlling impact connection and a current plastification effect.

Description

Technical Field

[0001] This invention relates to the field of high-speed impact connection technology, specifically to a device, method, and application of pulse current-assisted high-speed impact connection. Background Technology

[0002] High-speed impact bonding, a type of solid-state welding, uses a high-energy-density energy field or high-energy beam as external energy input. The interaction between the energy field and matter drives the material (flying plate) to move at high speed, impacting another material (substrate) at a certain angle. The connection between the two materials is achieved through plastic deformation and deformation heat in the impact zone. High-speed impact bonding offers advantages such as a short bonding process, the ability to bond a wide variety of metals, a small impact-affected zone, and joint strength greater than that of the base material, making it an excellent bonding technology.

[0003] High-speed impact bonding has two important characteristics. First, there is a wavy interface, where a wave-like interface morphology appears within the bonding area. This wavy interface increases the bonding area, effectively hindering crack propagation and providing a mechanical locking effect, significantly improving the joint's strength and stability. Second, there is the jetting effect: during the high-speed impact of the two metals, a thin layer of metal material is ejected at high speed from the contact surface at the impact point. This jet removes oxides and impurities from the metal surfaces, creating a clean bonding surface. These two characteristics are closely related to the mechanical properties of the materials.

[0004] However, high-speed impact welding is not suitable for joining brittle and hard metals. On the one hand, the high strength of the materials requires high impact velocities to form a wave-like interface and jet, which places high demands on the performance of the high-energy field actuator. On the other hand, in traditional high-speed impact welding, only alloys with an elongation of more than 15% can be used as substrates. Materials with poor plasticity will experience defects such as cracking during the impact process, reducing the bonding performance of the joint. Furthermore, when welding high-strength alloys with a yield strength ≥1000MPa, traditional impact welding requires the high-energy field actuator to provide even higher energy to deform and join the high-strength alloy, placing high demands on the performance of existing high-energy field actuator equipment. This limits the application of high-speed impact joining in advanced but brittle and hard materials such as Ti2AlNb and amorphous alloys.

[0005] Therefore, there is an urgent need to develop a new high-speed impact process that can reduce the energy requirements of high-energy field actuators and is compatible with brittle and hard metals, in order to overcome the limitations of existing technologies in the joining of materials such as intermetallic compound alloys, amorphous alloys, ultra-high strength steel, and refractory metal alloys. Summary of the Invention

[0006] To achieve one of the above objectives, this invention provides a pulsed current-assisted high-speed impact connection device, method, and application, solving the problem that brittle and hard materials are unsuitable for high-speed impact connections. The technical solution of this invention is implemented as follows:

[0007] In a first aspect, the present invention provides a device for pulsed current-assisted high-speed impact, comprising: an alloy plate to be connected, a high-energy field driver, an insulating plate, and a pulsed current-enhancing capacitor; the alloy plate to be connected comprises a flyer plate and a base plate; the flyer plate and the base plate are respectively connected to the two ends of the pulsed current-enhancing capacitor by wires to form a circuit to be conducted; the flyer plate and the base plate are separated by an insulating plate and have a cutout; the high-energy field driver is in contact with the flyer plate;

[0008] The pulsed current plasticizing capacitor needs to be charged in advance. The high-energy field driver drives the flying plate to deform and pass through the hollow area to impact the substrate at high speed. When the flying plate impacts and contacts the substrate, it generates current and completes the connection.

[0009] Preferably, the thickness of the flyboard is 0.8-3mm, the thickness of the substrate is 2-5mm, and the height of the insulating board is 2-5mm.

[0010] Preferably, the flyboard is located above the insulating plate; the insulating plate is located above the substrate.

[0011] Preferably, the plasticity of the fly plate is better than that of the substrate.

[0012] More preferably, the substrate comprises a hard and brittle metal with an elongation of ≥2% or a yield strength of ≥1000MPa, including intermetallic compound alloys, amorphous alloys, ultra-high strength steel, and refractory metal alloys.

[0013] Preferably, the high-energy field actuator includes an aluminum foil vaporization actuator, an explosive detonation module, a Lorentz force generator, and a laser ablation actuator.

[0014] Secondly, the present invention provides a pulse current-assisted high-speed impact connection method using the above-mentioned device, comprising the following steps:

[0015] S1. Before the experiment, the charging voltage of the pulse current plasticizing capacitor needs to be set and charged. The flyboard and the substrate are electrically connected to the two ends of the pulse current plasticizing capacitor, and placed separately by an insulating plate with a hole in the middle. The high-energy field driver is kept in contact with the flyboard.

[0016] S2. Activate the high-energy field driver to instantly drive the flying plate to deform and pass through the hollow area to impact the substrate at high speed. When the flying plate is about to contact the substrate, an electric arc will be generated between the two alloys to preheat the area to be connected.

[0017] S3. When the flying plate impacts and contacts the substrate, the circuit of the pulse current plastic capacitor forms a closed loop and discharges rapidly; the pulse current flows through the alloy matrix and the impact interface, the interface temperature rises, and the two alloy plates are connected under the instantaneous strong current coupling.

[0018] Preferably, in step S3, the charging voltage range of the pulse current plasticizing capacitor is 0.5 to 3kV. This voltage can be adjusted according to the high-energy field driver and the metal to be connected. When the voltage of the plasticizing capacitor is too high, a large area of ​​melting will occur at the impact interface, forming a brittle continuous intermetallic compound, resulting in low interface strength.

[0019] Preferably, in step S2, the speed of the fly plate required to form the connecting joint is lower than that of the fly plate in traditional high-speed impact connection. This speed is determined by the size of the plates to be connected, the type of material, and the voltage of the pulse current plasticizing capacitor, and is 100 to 400 m / s.

[0020] Preferably, in step S1, the alloy with better plasticity is used as the fly plate, and the alloy with poor plasticity is used as the substrate, so that the circuit of the pulse current plasticizing capacitor does not require an additional switch.

[0021] Preferably, in step S4, a crack-free waveform interface is formed at the interface through the synergistic effect of high-speed impact plastic deformation, deformation heat, and Joule heating and electroplastic effect of pulsed current.

[0022] Secondly, the present invention provides a pulse current-assisted high-speed impact connection method using the device described in the first aspect.

[0023] Thirdly, the present invention provides the application of the above-mentioned pulse current-assisted high-speed impact connection device and method in the field of high-speed impact connection.

[0024] Compared with the prior art, the advantages of the present invention are as follows:

[0025] (1) This invention combines the characteristics of high-speed impact and severe plastic deformation in impact connection process, introduces an external instantaneous strong pulse current to reduce the interface deformation resistance and improve plasticity, so as to achieve crack-free high-quality connection of brittle and hard materials.

[0026] (2) Compared with traditional long-time welding methods, the impact connection and pulse current discharge time of the present invention are shorter, no protective atmosphere is required, heating efficiency and energy consumption are low, and welding efficiency is high.

[0027] (3) Due to the small contact interface area and high current density, the present invention can achieve rapid heating and cooling of the interface to be connected without affecting the structure of the substrate.

[0028] (4) By plasticizing the interface region of the impact, the present invention reduces the requirements for the performance of high-energy field actuators when welding high-strength alloys with a yield strength ≥1000MPa, and can connect substrates with an elongation ≥2%. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the pulse current-assisted foil vaporization impact connection constructed in Embodiment 1 of the present invention; (a) before driving the impact; (b) during driving the impact; (c) after driving the impact;

[0031] Figure 2 This is a schematic diagram of the pulsed current assisted laser shock connection constructed in Embodiment 2 of the present invention; (a) before driving the shock; (b) after driving the shock.

[0032] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0033] 1-Pulsed current plasticizing capacitor; 2-Flying plate; 3-Insulating plate; 4-Substrate; 5-High energy field driver; 5a-Aluminum foil vaporization capacitor; 5b-Circuit switch; 5c-Aluminum foil; 5d-Insulating film; 5e-Aluminum foil vaporization capacitor current; 5f-High pressure gas cloud; 6-Pulsed current; 7-Waveform interface; 8-Jet; 9-Laser ablation driver; 9a-Laser; 9b-Constraint layer; 9c-Ablation layer; 9d-Laser. Detailed Implementation

[0034] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0035] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0036] In this document, the terms “containing,” “comprising,” or “including” are open-ended expressions, meaning they include the contents specified in this invention but do not exclude other aspects.

[0037] In this document, the terms “optional,” “optionally,” or “optional” generally refer to an event or condition that may, but may not, occur, and the description includes both cases in which the event or condition occurs and cases in which the event or condition does not occur.

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0039] Example 1

[0040] This embodiment provides a connection device and method for pulsed current assisted high-speed impact, wherein a 0.8mm thick NiTiHf shape memory alloy is used as the flyer plate 2, and a 2mm thick Ti2AlNb alloy plate (yield strength of 1000MPa, elongation of 4%) is used as the substrate 4. Taking the pulsed current assisted foil vaporization impact connection of the above two alloy plates as an example, ... Figure 1 As shown.

[0041] (1) As Figure 1 As shown in (a), the NiTiHf shape memory alloy plate 2 and the Ti2AlNb alloy plate 4 are isolated by an insulating plate 3 with a height of 2 mm. The aluminum foil vaporization actuator 5 is placed close to the NiTiHf shape memory alloy plate 2. In the aluminum foil vaporization actuator 5, a 0.02 mm thick polyurethane tape 5d is placed below a 0.07 mm thick aluminum foil 5c, which is connected to the aluminum foil vaporization capacitor 5a. At the same time, the NiTiHf shape memory alloy plate 2 and the Ti2AlNb alloy plate 4 are respectively connected to the pulse current plasticizing capacitor 1. The charging voltage of the aluminum foil vaporization capacitor 5a is 2 kV, and the pre-charging voltage of the pulse current plasticizing capacitor 1 is 2 kV. At this time, the electric field strength between the NiTiHf shape memory alloy plate 2 and the Ti2AlNb alloy plate 4 is 1000 V / mm, which is less than the breakdown field strength of air (3000 V / mm). At this time, the circuit of the pulse current plasticizing capacitor 1 is in the open state.

[0042] (2) At the start of the experiment, such as Figure 1 As shown in (b), when circuit switch 5b is closed, the circuit of aluminum foil vaporization capacitor 5a is completed and instantaneously discharged. The current 5e of aluminum foil vaporization capacitor instantaneously passes through aluminum foil 5c in about 20μs, causing aluminum foil 5c to vaporize and explode, producing about 10 4 The local high pressure of MPa 5f drives the NiTiHf plate 2 to move at a high speed of about 200m / s toward the Ti2AlNb plate 4;

[0043] (3) When the NiTiHf shape memory alloy plate 2 and the Ti2AlNb alloy plate 4 are about to come into contact, such as Figure 1 As shown in (c), the air is broken down to form an electric arc, which preheats the impact zone. At this time, the pulse current plasticizing capacitor 1 begins to discharge on its own, but the current is unstable. When the two alloy plates come into contact, the circuit of the pulse current plasticizing capacitor 1 forms a closed loop and discharges rapidly. The pulse current 6 passes through the NiTiHf matrix 2, the Ti2AlNb matrix 4 and the impact contact surface. At this time, the interface temperature rises rapidly due to the plastic deformation and deformation heat generated by the high-speed impact, as well as the electroplastic effect generated by the pulse current, and the plasticity of the alloy is greatly improved. At the same time, the tilted impact forms a metal jet 8 at the front edge of the impact point, which washes away the metal oxides and impurities on the surfaces to be joined, and forms a crack-free wavy interface 7 in the impact area. At this time, the NiTiHf shape memory alloy plate 2 and the Ti2AlNb alloy plate 4 are connected.

[0044] Example 2

[0045] This embodiment provides a connection method for pulsed current assisted high-speed impact, with a 1.5mm thick 5083 aluminum alloy as the flyer plate 2 and a 2mm thick amorphous alloy (Zr) as the flyer plate 2. 55 Cu 30 Al 10 Using Ni5 (yield strength 1500 MPa, elongation 2%) as substrate 4, and taking the pulsed current assisted laser shock bonding of the above two alloy plates as an example, as follows... Figure 2 As shown.

[0046] (1) As Figure 2 As shown in (a), the 5083 aluminum alloy plate 2 and the amorphous alloy plate 4 are isolated by an insulating plate 3 with a height of 2 mm; the laser ablation driver 9 is in close contact with the 5083 aluminum alloy plate 2, the ablation layer 9c is located below the constraint layer 9b, and the laser head 9a is placed above the constraint layer 9b; the 5083 aluminum alloy plate 2 and the amorphous alloy plate 4 are respectively connected to the two ends of the pulse current plasticizing capacitor 1, and the pre-charging voltage of the pulse current plasticizing capacitor 1 is 3kV; at this time, the electric field strength between the 5083 aluminum alloy plate 2 and the amorphous alloy plate 4 is 1500V / mm, which is less than the breakdown field strength of air 3000V / mm, and the circuit of the pulse current plasticizing capacitor 1 is in the open state.

[0047] (2) At the start of the experiment, laser 9d irradiates the ablation layer 9c through the constraint layer 9b. After absorbing the energy of laser 9d, the ablation layer 9c instantly vaporizes and explodes, driving the 5083 aluminum alloy 2 to move at a high speed of about 100m / s toward the amorphous alloy plate 4.

[0048] (3) Figure 2As shown in (b), when the 5083 aluminum alloy 2 is about to contact the amorphous alloy plate 4, an electric arc will form after the air is broken down. The electric arc can also preheat the material in the impact zone. At this time, the pulse current plasticizing capacitor 1 begins to discharge on its own, but the current is unstable. When the 5083 aluminum alloy 2 and the amorphous alloy 4 come into contact, the circuit of the pulse current plasticizing capacitor 1 forms a closed loop and discharges rapidly. The pulse current 6 passes through the 5083 aluminum alloy substrate 2, the amorphous alloy substrate 4 and the impact contact surface in about 18μs. The current causes the temperature of the amorphous alloy 4 at the interface to quickly reach the supercooled liquid phase region, which greatly improves its plasticity, makes interface deformation easier and avoids the generation of cracks, and finally forms a crack-free impact connection joint.

[0049] Example 3

[0050] This embodiment provides a connection method for pulsed current assisted high-speed impact. A 3mm thick H96 copper alloy is used as the flyer plate 2, and a 5mm thick 300M ultra-high-strength steel (yield strength of 1600MPa, elongation of 10%) is used as the substrate 4. Taking the pulsed current assisted laser impact connection of the above two alloy plates as an example, ... Figure 2 As shown.

[0051] (1) As Figure 2 As shown in (a), the H96 copper alloy plate 2 and the 300M ultra-high strength steel plate 4 are isolated by an insulating plate 3 with a height of 5mm; the laser ablation driver 9 is in close contact with the H96 copper alloy plate 2, the ablation layer 9c is located below the constraint layer 9b, and the laser head 9a is placed above the constraint layer 9b; the H96 copper alloy plate 2 and the 300M ultra-high strength steel plate 4 are respectively connected to the two ends of the pulse current plasticizing capacitor 1, and the pre-charging voltage of the pulse current plasticizing capacitor 1 is 0.5kV; at this time, the electric field strength between the H96 copper alloy plate 2 and the 300M ultra-high strength steel plate is 100V / mm, which is less than the breakdown field strength of air 3000V / mm, and the circuit of the pulse current plasticizing capacitor 1 is in the open state.

[0052] (2) At the start of the experiment, laser 9d irradiates the ablation layer 9c through the constraint layer 9b. After absorbing the energy of laser 9d, the ablation layer 9c instantly vaporizes and explodes, driving the H96 copper alloy plate 2 to move at a high speed of about 400m / s towards the 300M ultra-high strength steel plate 4.

[0053] (3) Figure 2As shown in (b), when the H96 copper alloy plate 2 is about to come into contact with the 300M ultra-high strength steel plate 4, an electric arc will be formed after the air is broken down. The electric arc can also preheat the material in the impact zone. At this time, the pulse current plasticizing capacitor 1 begins to discharge on its own, but the current is unstable. When the H96 copper alloy plate 2 and the 300M ultra-high strength steel plate 4 come into contact, the circuit of the pulse current plasticizing capacitor 1 forms a closed loop and discharges rapidly. The pulse current 6 passes through the H96 copper alloy plate 2, the 300M ultra-high strength steel plate 4 and the impact contact surface in about 8μs. The current causes the temperature of the 300M ultra-high strength steel 4 at the interface to rise rapidly, its plasticity is greatly improved, the interface deformation is easier, and finally a strong wavy interface 7 is formed.

[0054] Comparative Example 1

[0055] This comparative example provides a connection method for direct high-speed impact. The difference from Example 1 is that no pulse current auxiliary device is added, that is, the pulse current plasticizing capacitor 1 is removed. The rest is the same as Example 1.

[0056] In the impact test, due to the lack of current assistance, the plates to be connected have high yield strength and low elongation, and the impact interface deformation is small. This can lead to situations where the connection fails or the plates break, meaning that the connection is not achieved.

[0057] The embodiments described above are some, but not all, of the embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A device for pulse current-assisted high-speed impact connection, characterized in that, include: The components to be connected include an alloy plate, a high-energy field driver (5), an insulating plate (3), and a pulse current plasticizing capacitor (1); the alloy plate to be connected includes a flyer plate (2) and a substrate (4); the flyer plate (2) and the substrate (4) are respectively connected to the two ends of the pulse current plasticizing capacitor (1) by wires to form a circuit to be conducted; the flyer plate (2) and the substrate (4) are separated by the insulating plate (3) and have a cutout; the high-energy field driver (5) is in contact with the flyer plate (2); The pulse current plasticizing capacitor (1) needs to be charged in advance. The high-energy field driver (5) drives the flying plate (2) to deform and pass through the hollow area to impact the substrate (4) at high speed. When the flying plate (2) impacts and contacts the substrate (4), it generates current and completes the connection.

2. The device for pulse current-assisted high-speed impact connection according to claim 1, characterized in that, The thickness of the flyboard (2) is 0.8-3 mm, the thickness of the substrate (4) is 2-5 mm, and the height of the insulating plate (3) is 2-5 mm.

3. The device for pulse current-assisted high-speed impact connection according to claim 1, characterized in that, The flyboard (2) is located above the insulating plate (3); the insulating plate (3) is located above the substrate (4).

4. The device for pulse current-assisted high-speed impact connection according to claim 1, characterized in that, The plasticity of the fly plate (2) is better than that of the substrate (4).

5. The device for pulse current-assisted high-speed impact connection according to claim 1, characterized in that, The substrate (4) comprises a hard and brittle metal with an elongation of ≥2% or a yield strength of ≥1000MPa.

6. The device for pulse current-assisted high-speed impact connection according to claim 1, characterized in that, The high-energy field actuator (5) includes an aluminum foil vaporization actuator, an explosive detonation module, a Lorentz force generator, and a laser ablation actuator.

7. A pulse current-assisted high-speed impact connection method using the device described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1. Before the experiment, the charging voltage of the pulse current plasticizing capacitor (1) needs to be set and charged. The flying plate (2) and the substrate (4) are electrically connected to the two ends of the pulse current plasticizing capacitor (1) and placed apart by the insulating plate (3), with a hole in the middle. The high energy field driver (5) is in contact with the flying plate (2). S2. Turn on the high-energy field driver (5) to instantly drive the flying plate (2) to deform and pass through the hollow area to impact the substrate (4) at high speed. When the flying plate (2) is about to contact the substrate (4), an electric arc will be generated between the two alloys to preheat the area to be connected. S3. When the flying plate (2) impacts and contacts the substrate (4), the circuit of the pulse current plasticizing capacitor (1) forms a closed loop and discharges rapidly; the pulse current (6) flows through the alloy matrix and impact interface, the interface temperature rises, and the two alloy plates are connected under the instantaneous strong current coupling effect.

8. The pulse current-assisted high-speed impact connection method according to claim 7, characterized in that, In step S3, the charging voltage range of the pulse current plasticizing capacitor (1) is 0.5 to 3 kV.

9. The pulse current-assisted high-speed impact connection method according to claim 7, characterized in that, In step S2, the speed of the flying board (2) is 100-400 m / s.

10. The application of the pulse current-assisted high-speed impact connection method as described in claims 7-9 in the field of high-speed impact connection.

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