Method and device for electric pulse-ultrasonic synergistic driving of sintering and infiltration of tungsten-copper alloy

Abstract

A method and apparatus for electro-pulse and ultrasonic synergistic driven melt infiltration sintering of tungsten-copper alloys are disclosed. The apparatus, centered on a high-temperature vacuum furnace, integrates an upper conductive mechanism, a middle limiting and insulating mechanism, and a lower conductive vibration mechanism, along with a temperature controller to achieve precise control of pressure, vacuum, temperature, electro-pulse, and ultrasonic vibration parameters during melt infiltration sintering. In preparing the tungsten-copper alloy, tungsten-copper alloy powder is first prepared and mixed in a specified ratio. The sample is placed in a sleeve structure within the furnace, a constant pressure is applied, and a vacuum is evacuated to a set value. Simultaneously, ultrasonic vibration and furnace heating are initiated. During the holding phase, pulsed direct current is applied. After sintering, the alloy is cooled under vacuum with the furnace, ultimately yielding a high-density tungsten-copper alloy. This invention effectively solves the problems of low density, high sintering temperature, long cycle time, and component segregation associated with traditional processes. The prepared alloy exhibits high density, uniform microstructure, and tight tungsten-copper interface bonding, making it suitable for tungsten-copper alloy preparation and applicable to a wide range of fields, including high-end electronics and aerospace.

Description

TECHNICAL FIELD

[0001] The application relates to a method and device for infiltrating sintering tungsten-copper alloy driven by electric pulse and ultrasonic waves, and belongs to the technical field of alloy preparation. BACKGROUND

[0002] Tungsten-copper alloy is widely used in high-end electronics and aerospace fields due to its high-temperature resistance, arc resistance and high electrical and thermal conductivity. Such applications require the material to have high density and uniformity to avoid early failure. Existing preparation processes (such as powder metallurgy and infiltration method) are limited by the poor mutual solubility and wettability of tungsten and copper, which often leads to copper phase aggregation, residual porosity and weak interface bonding, making it difficult to meet the density requirements. Moreover, traditional methods often require high-temperature and long-time sintering, which is energy-consuming, low-efficient and easy to cause grain coarsening. Although electric field assisted sintering has the advantages of fast heating and low temperature, it cannot solve the complex pore filling problem of tungsten-copper system with single electric pulse, and large-size samples are prone to uneven densification. The introduction of ultrasonic vibration can improve the wettability and promote exhaust through mechanical disturbance and cavitation effect. Therefore, the combination of electric pulse and ultrasonic wave can break through the bottleneck.

[0003] However, there is no system device and method for the synergistic infiltration sintering of high-density tungsten-copper alloy driven by electric pulse and ultrasonic waves reported at present, and the development of such integrated technology with low temperature, short time and high performance has important application value. SUMMARY

[0004] The application aims to solve the problems of low density, high sintering temperature, long cycle, composition segregation and poor interface bonding in the preparation process of existing tungsten-copper alloy, and provides a device and method for infiltrating sintering tungsten-copper alloy driven by electric pulse and ultrasonic waves.

[0005] The technical scheme realized by the application is as follows: a device for infiltrating sintering tungsten-copper alloy driven by electric pulse and ultrasonic waves, comprising a high-temperature furnace, a pulse direct current power supply and a vacuum pump.

[0006] The high-temperature furnace comprises an upper conductive mechanism, a middle limiting insulation mechanism, a lower conductive vibration mechanism, a vacuum degree monitoring and control module and a temperature monitoring and control module. The high-temperature furnace is provided with a movable clamping column, and a temperature controller is installed outside the high-temperature furnace. The vacuum pump is connected to the vacuum hole at the bottom of the vacuum furnace through a pipeline; the positive and negative electrodes of the pulse direct current power supply are connected to the upper conductive mechanism and the lower conductive vibration mechanism of the high-temperature furnace through wires.

[0007] The high-temperature vacuum furnace is a core bearing structure, and the upper conductive mechanism, the middle limiting insulation mechanism and the lower conductive vibration mechanism are arranged in the high-temperature vacuum furnace from top to bottom.

[0008] The upper conductive mechanism includes an upper conductive molybdenum rod and an upper molybdenum block. The conductive molybdenum rod and the upper molybdenum block are linked with a pressure regulator, rotary valve, and iron column outside the furnace body. The pressure is precisely transmitted to the upper electrode molybdenum block by raising and lowering the iron column, thereby achieving pressure application and position fixation of the sample. One end of the upper conductive molybdenum rod is vertically connected to the center of the upper molybdenum block. The upper conductive molybdenum rod is placed inside the iron column and moves up and down with the iron column.

[0009] The middle limiting furnace and insulation mechanism include graphite pads and ceramic vertical blocks; the upper graphite pads and the lower graphite pads are respectively installed at the upper and lower ends of the ceramic vertical blocks to form a sleeve structure, and the space between the upper and lower graphite pads and the ceramic vertical blocks is the area for placing the workpiece.

[0010] The lower conductive vibration mechanism consists of a support platform, an ultrasonic vibration device, and a detachable movable retaining post. The ultrasonic vibration device is integrated with the support platform to provide continuous and adjustable ultrasonic vibration for the sample. The movable retaining post is used for disassembling, installing, and cleaning the ultrasonic vibration device. The support platform includes a lower conductive molybdenum rod and a lower molybdenum block. The lower conductive molybdenum rod is vertically installed at the center of the lower molybdenum block and is connected to the ultrasonic vibration device. The lower molybdenum block serves as the support surface of the support platform and contacts the lower graphite pad.

[0011] In conjunction with the aforementioned mechanisms, the vacuum monitoring and control module and the temperature monitoring and regulation module enable precise regulation of pressure, vacuum, temperature, electrical pulse, and ultrasonic vibration parameters during the melting and infiltration sintering process.

[0012] The graphite pad is made of high-purity isostatic graphite with a purity of ≥99.9% and a thickness of 10~20mm, serving to conduct electricity and support the sample; the ceramic vertical block is made of alumina high-temperature resistant ceramic with a service temperature of ≥1600℃, with a thickness of 10~15mm, and its height matches the sample size, serving to limit position and provide electrical insulation.

[0013] The vibration frequency adjustment range of the ultrasonic vibration device is 20~80kHz, and the vibration power adjustment range is 50~200W; the output parameter adjustment range of the pulse DC power supply is: pulse voltage 80~150V, pulse current density 300~800A / cm², and pulse frequency 50~500Hz.

[0014] A method for electro-pulse ultrasonic co-driven melting and sintering of tungsten-copper alloys, comprising the following steps: (1) Raw material preparation and mixing: Prepare tungsten copper alloy powder according to the mass ratio W:Cu=70~90:30~10, wherein the average particle size of pure tungsten powder is 10~50μm and the average particle size of high-purity copper powder is 1~5μm; place the mixed powder in a mixing device and stir and mix under the protection of inert gas to obtain a tungsten copper alloy mixed powder with uniform composition.

[0015] (2) Sample loading and positioning: Open the furnace cover of the high temperature vacuum furnace, place a sleeve consisting of graphite pads and ceramic vertical blocks on the support platform of the lower conductive vibration mechanism inside the furnace, place the tungsten copper alloy mixed powder in the center of the sleeve, and ensure that the upper and lower surfaces of the powder are in full contact with the graphite pads.

[0016] (3) Pressure application and vacuum evacuation: Cover the high-temperature vacuum furnace with the lid, and drive the upper conductive mechanism connected to the iron column to descend through the pressure regulator, so that the upper electrode molybdenum block is in full contact with the surface of the graphite pad block at the upper end of the sample. Apply a constant pressure of 20~50MPa, tighten the rotary valve to fix the position of the upper electrode; start the vacuum pump to evacuate the furnace to 5×10 -3 Pa, and maintains a stable vacuum level inside the furnace through a vacuum monitoring and control module.

[0017] (4) Ultrasonic start-up and heating and heat preservation: Maintain a vacuum environment, start the ultrasonic vibration device and set the ultrasonic parameters, and at the same time start the heating tube and temperature controller of the high temperature vacuum furnace. Set the heating rate of 20~30℃ / min to raise the temperature inside the furnace to 1100~1400℃. After reaching the target temperature, enter the heat preservation stage and keep warm for 10~20min. The temperature is controlled in real time through thermocouples and temperature monitoring modules throughout the process.

[0018] (5) Application of electric pulse and melting infiltration sintering: During the heat preservation stage, the pulsed DC power supply is started, and the pulsed DC power is applied to the sample through the upper and lower conductive mechanisms and the electric pulse parameters are set. The Joule heating and electric field activation effect of the electric pulse, together with the mechanical disturbance and cavitation effect of ultrasonic vibration, promote the melting infiltration of copper phase and densification of tungsten skeleton. The total sintering time is controlled within 40~60min.

[0019] (6) Electrode recovery and cooling molding: After the heat preservation sintering is completed, the upper electrode molybdenum rod and upper electrode molybdenum block are pulled back before the tungsten copper alloy is in a molten state and not completely solidified. Then the pulsed DC power supply and ultrasonic vibration device are disconnected, and the vacuum environment inside the furnace is maintained so that the sample is slowly cooled to room temperature with the furnace. After cooling is completed, the sample is taken out to obtain a high-density tungsten copper alloy.

[0020] The inert gas is argon; the mixing equipment is either a ball mill or a V-type mixer; when using a ball mill, the stirring speed and mixing time are designed to ensure uniform powder composition and prevent oxidation and segregation. When using a ball mill, the stirring speed and mixing time are as follows: stirring speed 200–300 rpm, mixing time 30–60 min; when using a V-type mixer, the stirring speed is 30–60 rpm, mixing time 60–120 min.

[0021] The ultrasonic parameters of the ultrasonic vibration device are set as follows: vibration frequency 20~80kHz, vibration power 50~200W, and the ultrasonic vibration device continues to work after startup until the end of the heat preservation stage.

[0022] The positive and negative terminals of the pulsed DC power supply are connected to the upper conductive mechanism and the lower conductive vibration mechanism via wires. Pulsed current is supplied to the tungsten-copper alloy powder through the conductive molybdenum rods and graphite pads of the upper and lower conductive vibration mechanisms. The electrical pulse parameters are set as follows: pulse voltage 80~150V, pulse current density 300~800A / cm², and pulse frequency 50~500Hz. These parameters can be adaptively adjusted according to the tungsten-copper alloy mass ratio and sample size.

[0023] The working principle of this invention is as follows: Figure 4 As shown, tungsten-copper alloy powder 7 is positioned between upper graphite pad 6 and lower graphite pad 8. Electrical pulses generate Joule heating within the tungsten-copper alloy powder, achieving rapid heating. Compared to traditional processes, this significantly shortens the heating time. The electric field activation effect also accelerates tungsten-copper atom diffusion, significantly improving sintering densification efficiency. Ultrasonic vibration, on the one hand, disrupts the adsorption layer at the solid-liquid interface, enhancing the wettability of the copper liquid on the tungsten framework and allowing for more complete melting and penetration. On the other hand, mechanical vibration promotes gas expulsion from pores, reducing porosity defects and alleviating stress concentration during sintering, thus improving microstructure uniformity. The synergistic effect of these two processes ultimately yields a highly dense tungsten-copper alloy 9 in a short time. Furthermore, the entire process is conducted in a vacuum environment, preventing gas interference with the sintering process, effectively preventing alloy oxidation, and ensuring the stability of the alloy's composition and properties.

[0024] The beneficial effects of this invention are that by using electric pulse and ultrasonic vibration in synergistic driving to melt infiltrate and sinter tungsten copper alloy, the heating time is shortened and the sintering densification efficiency is improved, resulting in a highly dense tungsten copper alloy in a short time, which greatly improves the sintering efficiency.

[0025] This invention enables the short-time and efficient preparation of tungsten-copper alloys, effectively solving problems such as low density, high sintering temperature, long cycle time, component segregation, and poor interfacial bonding in traditional processes. The prepared alloy has high density, uniform microstructure, and tight tungsten-copper interfacial bonding. Furthermore, the entire process is conducted in a vacuum environment, preventing alloy oxidation and ensuring performance stability.

[0026] This invention is applicable to the preparation of tungsten-copper alloys and can be widely used in high-end electronics, aerospace and other fields. Attached Figure Description

[0027] Figure 1 A schematic diagram of the principle of an electrical pulse and ultrasonic co-driven melting and infiltration sintering device for tungsten-copper alloys. Figure 2 This is a schematic diagram of the high-temperature furnace structure; Figure 3 This is a cross-sectional view (AA) of the high-temperature furnace structure. Figure 4 A schematic diagram illustrating the principle of the electro-pulse ultrasonic co-driven melting and infiltration sintering method for tungsten-copper alloys. Figure 5 This describes a process for preparing tungsten-copper alloys by electro-pulse ultrasonic co-driven melting and infiltration sintering. In the diagram: 1 is a high-temperature furnace; 2 is a temperature controller; 3 is a movable retaining post for the high-temperature furnace; 4 is a pulsed DC power supply; 5 is a vacuum pump; 6 is an upper graphite pad; 7 is tungsten-copper alloy powder; 8 is a lower graphite pad; 9 is a tungsten-copper alloy sample; 301 is a rotary valve; 302 is an iron column; 303 is a high-temperature furnace cover; 304 is a porous corundum tube; 305 is an ultrasonic vibration device; 306 is a ceramic vertical block; 307 is a detachable high-temperature furnace base; 308 is the outer shell; 309 is a vacuum port; 310 is a movable retaining post; 311 is an upper conductive molybdenum rod; 312 is a screw; 313 is the sample placement area; 314 is an insulation layer; 315 is a high-temperature furnace heating tube; 316 is a support platform; 317 is a lower conductive molybdenum rod. Detailed Implementation

[0028] The specific embodiments of the present invention are shown in the figure.

[0029] like Figure 1 As shown in the figure, this embodiment discloses an apparatus for electro-pulse ultrasonic co-driven melting and infiltration sintering of tungsten-copper alloy, comprising a high-temperature furnace 1, a pulsed DC power supply 4, and a vacuum pump 5. The high-temperature furnace 1 is equipped with a high-temperature furnace movable retaining post 3, and a temperature controller 2 is installed outside the high-temperature furnace 1. The vacuum pump 5 is connected to the vacuum furnace via pipeline. like Figure 2 and Figure 3 As shown, the high-temperature furnace 1 in this embodiment includes an upper conductive mechanism, a middle limiting insulation mechanism, a lower conductive vibration mechanism, a vacuum monitoring and control module, and a temperature monitoring and control module. The positive and negative terminals of the pulsed DC power supply 4 are connected to the upper conductive mechanism and the lower conductive vibration mechanism of the high-temperature furnace 1 respectively through wires.

[0030] The upper conductive mechanism in this embodiment includes an upper conductive molybdenum rod 311, an upper molybdenum block, and an upper graphite pad 6. The upper conductive molybdenum rod and the upper molybdenum block are linked with a pressure regulator, a rotary valve 301, and an iron column 302 outside the furnace body. The pressure is precisely transmitted to the upper electrode molybdenum block by raising and lowering the iron column 302, thereby achieving pressure application and position fixation of the sample. One end of the upper conductive molybdenum rod 311 is vertically connected to the center of the upper molybdenum block. The upper conductive molybdenum rod 311 is placed inside the iron column 302 and moves up and down with the iron column.

[0031] The middle limiting furnace and insulation mechanism of this embodiment include a graphite pad and a ceramic vertical block 306; the upper graphite pad 6 and the lower graphite pad 8 are respectively installed at the upper and lower ends of the ceramic vertical block 306 to form a sleeve structure, and the space between the upper and lower graphite pads and the ceramic vertical block is the workpiece placement area 313.

[0032] The lower conductive vibration mechanism in this embodiment consists of a support platform 316, an ultrasonic vibration device 305, and a movable retaining post 310. The ultrasonic vibration device 305 is integrated with the support platform 316 to provide continuous and adjustable ultrasonic vibration for the sample. The movable retaining post 310 is used for disassembling, installing, and cleaning the ultrasonic vibration device 305. The support platform includes a lower conductive molybdenum rod 317 and a lower molybdenum block. The lower conductive molybdenum rod 317 is vertically installed at the center of the lower molybdenum block and is connected to the ultrasonic vibration device 305. The lower molybdenum block serves as the support surface of the support platform and contacts the lower graphite pad 8.

[0033] The high-temperature furnace in this embodiment also includes a high-temperature furnace cover 303, a porous corundum tube 304, an outer shell 308, a vacuum hole 309, a heat insulation layer 314, and a high-temperature furnace heating tube 315.

[0034] Example 1 (1) Raw material preparation: Weigh 70% pure tungsten powder (average particle size 20μm) and 30% high-purity copper powder (average particle size 3μm) according to the mass ratio; place the weighed tungsten powder and copper powder in a ball mill and stir and mix at 200 rpm for 30 min under argon protection atmosphere to obtain a uniformly mixed powder.

[0035] (2) Sample loading: Open the furnace lid of the high temperature vacuum furnace, and place two high temperature resistant alumina ceramic vertical blocks (12 mm high and 12 mm thick) symmetrically on the graphite pad block (15 mm thick) of the lower electrode at the bottom of the furnace chamber; spread about 50 grams of the prepared tungsten copper alloy mixed powder evenly on the graphite pad block between the ceramic vertical blocks, ensuring that the upper and lower surfaces of the sample are flat and in full and tight contact with the graphite pad block.

[0036] (3) Pressure and vacuum settings: Cover the high temperature furnace cover 303, apply a constant pressure of 20MPa to drive the upper conductive molybdenum rod 311 and the upper molybdenum block to slowly descend and rotate the valve 301 to fix the position of the upper electrode, so that the upper electrode contacts the upper graphite pad 6 and the upper surface of the sample to ensure pressure stability; turn on the vacuum pump 5 to pump the vacuum degree in the furnace to 5×10⁻³ Pa, and keep it stable through the vacuum degree monitoring module.

[0037] (4) Ultrasonic vibration and heating start-up: Start the ultrasonic vibration device 305, set the vibration frequency to 40 kHz and the vibration power to 100 W; turn on the temperature controller 2 and the high temperature furnace heating tube 315, set the heating rate to 25℃ / min, and under the continuous action of vacuum and ultrasonic waves, the high temperature furnace starts to heat up. When the temperature reaches 1200℃, it enters the heat preservation stage and is kept warm for 15 min.

[0038] (5) Applying electrical pulse: During the heat preservation stage, start the pulse DC power supply 4 and set the pulse parameters: pulse voltage 100 V, pulse current density 500 A / cm², pulse frequency 200 Hz; the pulse DC power supply applies pulse current to the sample through the upper and lower conductive mechanisms, and the total sintering time is controlled at 50 min.

[0039] (6) Cooling and Shaping: After the heat preservation sintering is completed, before the tungsten-copper alloy solidifies, the upper electrode is quickly withdrawn, and then the pulse power supply 4 and ultrasonic vibration device 305 are disconnected; the vacuum environment inside the furnace is maintained, and the sample is cooled to room temperature with the furnace; the furnace lid is opened, and the sintered W-70Cu alloy sample is taken out. The alloy has a density of more than 99.5% of the theoretical density, a uniform structure, no obvious pores or copper phase aggregation, and a tight bond at the tungsten-copper interface.

[0040] Example 2 (1) Raw material preparation: Weigh 80% pure tungsten powder (average particle size 30μm) and 20% high-purity copper powder (average particle size 2μm) according to the mass ratio; place the weighed powder in a V-type mixer and mix at a speed of 30 rpm for 60 min to obtain a uniform mixed powder.

[0041] (2) Sample loading: Open the high-temperature vacuum furnace and place two alumina ceramic vertical blocks (14mm high and 14mm thick) on the graphite pad (18mm thick) of the lower electrode; place about 80g of mixed powder sample on the graphite pad, ensuring that the sample and the graphite pad are in good contact without gaps.

[0042] (3) Pressure and vacuum settings: Close the high-temperature furnace cover 303, lower the upper electrode molybdenum rod 311 and apply a constant pressure of 30MPa, and tighten the lock nut to fix the position of the upper electrode; start the vacuum pump 5 to evacuate the furnace to 5×10 -3 Pa remains stable.

[0043] (4) Ultrasonic and heating start-up: Turn on the ultrasonic vibration device 305, set the frequency to 60 kHz and the power to 150W; set the temperature controller 2 to a heating rate of 20℃ / min, start the heating tube 315 to heat up, and enter the heat preservation stage when the temperature reaches 1300℃, and keep warm for 12min.

[0044] (5) Applying electrical pulse: When the heat preservation begins, turn on the pulse DC power supply 4 and set the parameters: pulse voltage 120V, pulse current density 600A / cm², pulse frequency 300Hz; the total sintering time is controlled at 45min.

[0045] (6) Cooling and forming: After the heat preservation is completed, the upper electrode is pulled back before the alloy solidifies, and the power supply and ultrasonic device are disconnected; after cooling to room temperature in the furnace, the W-80Cu alloy sample is taken out. The alloy has a density of over 99.2%, and the microstructure shows that the tungsten particles are evenly distributed, the copper phase fully fills the pores of the tungsten skeleton, there is no component segregation, and the interface bonding is good.

Claims

1. A device for electro-pulse ultrasonic co-driven melting and sintering of tungsten-copper alloys, comprising a high-temperature furnace, a pulsed DC power supply, and a vacuum pump; characterized in that, The high-temperature furnace includes an upper conductive mechanism, a middle limiting insulation mechanism, a lower conductive vibration mechanism, a vacuum monitoring and control module, and a temperature monitoring and control module. The high-temperature vacuum furnace is the core load-bearing structure, and its interior is arranged from top to bottom as an upper conductive mechanism, a middle limiting and insulating mechanism, and a lower conductive vibration mechanism. The upper conductive mechanism includes an upper conductive molybdenum rod and a molybdenum block. The conductive molybdenum rod and molybdenum block are linked with the pressure regulator, rotary valve and iron column outside the furnace body. The pressure is accurately transmitted to the upper electrode molybdenum block by raising and lowering the iron column, so as to apply pressure to the sample and fix its position. The intermediate limiting insulation mechanism includes a graphite pad and a ceramic vertical block; the upper graphite pad and the lower graphite pad are respectively installed at the upper and lower ends of the ceramic vertical block to form a sleeve structure, and the space between the upper and lower graphite pads and the ceramic vertical block is the area for placing the workpiece. The lower conductive vibration mechanism consists of a support platform, an ultrasonic vibration device, and a detachable movable locking post. The ultrasonic vibration device is integrated with the support platform to provide continuous and adjustable ultrasonic vibration for the sample. The movable locking post is used for disassembly, installation, and cleaning of the ultrasonic vibration device. In conjunction with the aforementioned mechanisms, the vacuum monitoring and control module and the temperature monitoring and regulation module enable precise regulation of pressure, vacuum, temperature, electrical pulse, and ultrasonic vibration parameters during the melting and infiltration sintering process.

2. The device for electro-pulse ultrasonic synergistic driving of melting and infiltration sintering of tungsten-copper alloy according to claim 1, characterized in that, The graphite pad is made of high-purity isostatic graphite with a purity of ≥99.9% and a thickness of 10~20mm, serving to conduct electricity and support the sample; the ceramic vertical block is made of alumina high-temperature resistant ceramic with a service temperature of ≥1600℃, with a thickness of 10~15mm, and its height matches the sample size, serving to limit position and provide electrical insulation.

3. The device for electro-pulse ultrasonic synergistic driving of melting and sintering tungsten-copper alloy according to claim 1, characterized in that, The vibration frequency adjustment range of the ultrasonic vibration device is 20~80kHz, and the vibration power adjustment range is 50~200W; the output parameter adjustment range of the pulse DC power supply is: pulse voltage 80~150V, pulse current density 300~800A / cm², and pulse frequency 50~500Hz.

4. A method for sintering tungsten-copper alloys using an apparatus for electro-pulse ultrasonic co-driven melting and infiltration sintering as described in any one of claims 1 to 3, characterized in that, The method steps are as follows: (1) Raw material preparation and mixing: Prepare tungsten copper alloy powder according to the mass ratio W:Cu=70~90:30~10, wherein the average particle size of pure tungsten powder is 10~50μm and the average particle size of high-purity copper powder is 1~5μm; place the mixed powder in a mixing device and stir and mix under the protection of inert gas to obtain a tungsten copper alloy mixed powder with uniform composition. (2) Sample loading and positioning: Open the furnace cover of the high temperature vacuum furnace, place a sleeve consisting of graphite pads and ceramic vertical blocks on the support platform of the lower conductive vibration mechanism inside the furnace, place the tungsten copper alloy mixed powder in the center of the sleeve, and ensure that the upper and lower surfaces of the powder are in full contact with the graphite pads. (3) Pressure application and vacuum evacuation: Cover the high-temperature vacuum furnace with the lid, and drive the upper conductive mechanism connected to the iron column to descend through the pressure regulator, so that the upper electrode molybdenum block is in full contact with the surface of the graphite pad block at the upper end of the sample. Apply a constant pressure of 20~50MPa, tighten the rotary valve to fix the position of the upper electrode; start the vacuum pump to evacuate the furnace to 5×10 -3 Pa, and maintains a stable vacuum level inside the furnace through a vacuum monitoring and control module; (4) Ultrasonic start-up and heating and heat preservation: Maintain a vacuum environment, start the ultrasonic vibration device and set the ultrasonic parameters, and at the same time start the heating tube and temperature controller of the high temperature vacuum furnace. Set the heating rate of 20~30℃ / min to raise the temperature inside the furnace to 1100~1400℃. After reaching the target temperature, enter the heat preservation stage and keep warm for 10~20min. The temperature is controlled in real time through thermocouples and temperature monitoring module throughout the process. (5) Application of electric pulse and melting infiltration sintering: During the heat preservation stage, the pulsed DC power supply is started, and the pulsed DC power is applied to the sample through the upper and lower conductive mechanisms and the electric pulse parameters are set. The Joule heating and electric field activation effect of the electric pulse, together with the mechanical disturbance and cavitation effect of ultrasonic vibration, promote the melting infiltration of copper phase and densification of tungsten skeleton. The total sintering time is controlled within 40~60min. (6) Electrode recovery and cooling molding: After the heat preservation sintering is completed, the upper electrode molybdenum rod and upper electrode molybdenum block are pulled back before the tungsten copper alloy is in a molten state and not completely solidified. Then the pulsed DC power supply and ultrasonic vibration device are disconnected, and the vacuum environment inside the furnace is maintained so that the sample is slowly cooled to room temperature with the furnace. After cooling is completed, the sample is taken out to obtain a high-density tungsten copper alloy.

5. The method for electro-pulse ultrasonic synergistic driven melting and infiltration sintering of tungsten-copper alloy according to claim 4, characterized in that, The inert gas is argon; the mixing equipment is either a ball mill or a V-type mixer; when using a ball mill, the stirring speed is 200-300 rpm and the mixing time is 30-60 min; when using a V-type mixer, the stirring speed is 30-60 rpm and the mixing time is 60-120 min.

6. The method for electro-pulse ultrasonic synergistic driven melting and infiltration sintering of tungsten-copper alloy according to claim 4, characterized in that, The ultrasonic parameters of the ultrasonic vibration device are set as follows: vibration frequency 20~80kHz, vibration power 50~200W, and the ultrasonic vibration device continues to work after startup until the end of the heat preservation stage.

7. The method for electro-pulse ultrasonic synergistic driven melting and infiltration sintering of tungsten-copper alloy according to claim 4, characterized in that, The electrical pulse parameters are set as follows: pulse voltage 80~150V, pulse current density 300~800A / cm², and pulse frequency 50~500Hz. The electrical pulse and ultrasonic vibration parameters can be adaptively adjusted according to the tungsten-copper alloy mass ratio and sample size.

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