Refractory metal ultra-high temperature vacuum superplastic forming apparatus and method

Abstract

The present application relates to the technical field of material processing, and discloses a kind of refractory metal ultra-high temperature vacuum superplastic forming equipment and method, comprising, pressure loading system;Heating system is arranged in the pressure loading system inside;With the heating system is connected with ultra-high temperature gas expansion system;Located in the heating system outside vacuum system, and;Argon circulation fast cooling system is arranged in the heating system outside.The present application breaks through the processing problem of tungsten, molybdenum and other alloys due to high melting point, high hardness and room temperature brittleness, can integrally manufacture the complex curved surface, thin wall, deep hole and hollow conformal runner structure difficult to process by traditional method, so that its performance advantage under high temperature environment can be fully played in the field of aerospace, nuclear industry and the like, and the formed part reaches nearly complete densification.

Description

Technical Field

[0001] This invention relates to the field of materials processing technology, and in particular to an equipment and method for ultra-high temperature vacuum superplastic forming of refractory metals. Background Technology

[0002] With the development of aerospace, nuclear industry and other fields, higher requirements have been placed on the high temperature resistance, structural strength and integrity of hot-end components such as engine nozzles and reactor structural components. It is necessary to use refractory metals such as tungsten and molybdenum to process components with complex geometric structures in order to achieve structural weight reduction and reduce weld length.

[0003] Refractory metals such as tungsten and molybdenum are brittle materials. Currently, they are typically manufactured using powder metallurgy. However, parts produced using this method have high porosity and experience volume shrinkage during sintering. Thin-walled, low-stiffness areas of complex components are prone to deformation during sintering, making it difficult to meet the requirements for stable production. At room temperature, refractory metals such as tungsten and molybdenum are generally brittle and difficult to process; at high temperatures, their oxidation resistance is very poor, making traditional plastic forming methods such as forging and extrusion difficult to achieve.

[0004] Superplastic forming technology, as an advanced material forming process, enables the one-piece forming of complex-shaped parts under relatively low stress. Traditional superplastic forming equipment heats to temperatures below 1200℃, and the forming process takes place in an atmospheric environment, which cannot effectively limit the oxidation of the workpiece. Vacuum superplastic forming equipment typically heats to temperatures not exceeding 1400℃, which cannot reach the superplastic temperatures of molybdenum alloys (approximately 1600℃) and tungsten alloys (approximately 2000℃), and therefore cannot perform superplastic forming of refractory metals. Summary of the Invention

[0005] The above-mentioned technical problems are solved by the following technical solution: The present invention proposes an ultra-high temperature vacuum superplastic forming equipment for refractory metals, which includes: a pressure loading system; a heating system disposed inside the pressure loading system; an ultra-high temperature gas expansion system connected to the heating system; a vacuum system located outside the heating system; and an argon gas circulation rapid cooling system disposed outside the heating system.

[0006] In a preferred embodiment of the refractory metal ultra-high temperature vacuum superplastic forming equipment of the present invention: the pressure loading system includes a bearing bed; an upper loading platform located above the bearing bed; and a lower loading platform located below the bearing bed.

[0007] In a preferred embodiment of the refractory metal ultra-high temperature vacuum superplastic forming equipment of the present invention: the heating system includes a heating furnace cavity; a graphite heat insulation layer placed on the inner surface of the heating furnace cavity; and water-cooled heating electrodes and graphite heating rods disposed on the heating furnace cavity.

[0008] In a preferred embodiment of the refractory metal ultra-high temperature vacuum superplastic forming equipment of the present invention: the ultra-high temperature gas expansion system includes a gas source device, a filter disposed downstream of the gas source device, a pressure regulator disposed at the output end of the filter, and a ball valve disposed at the output end of the pressure regulator.

[0009] In a preferred embodiment of the refractory metal ultra-high temperature vacuum superplastic forming equipment of the present invention: the ultra-high temperature gas expansion system further includes an electronic regulator, an electronic pressure gauge located downstream of the electronic regulator, and a buffer tank located between the electronic regulator and the electronic pressure gauge; a main pneumatic valve is also provided downstream of the electronic pressure gauge; the main pneumatic valve is connected in parallel with the upper platform pneumatic valve, the lower platform pneumatic valve and the vacuum valve.

[0010] In a preferred embodiment of the refractory metal ultra-high temperature vacuum superplastic forming equipment of the present invention: the ultra-high temperature gas expansion system further includes a vacuum gauge and a vacuum pump disposed downstream of the vacuum valve; a high temperature connector is disposed downstream of the upper platform pneumatic valve, and a graphite high temperature gas pipe is disposed downstream of the high temperature connector; an exhaust valve is disposed at the end of the ultra-high temperature gas expansion system.

[0011] In a preferred embodiment of the refractory metal ultra-high temperature vacuum superplastic forming equipment of the present invention: the ultra-high temperature gas expansion system further includes a gas heating device and an inlet temperature measuring device disposed around the graphite high temperature gas pipe. The gas then flows through the gas heating device and is heated. Its temperature is monitored by the inlet temperature measuring device to prevent overcooled gas from entering the furnace cavity and cooling the refractory metal workpiece.

[0012] In a preferred embodiment of the refractory metal ultra-high temperature vacuum superplastic forming equipment of the present invention: the ultra-high temperature gas expansion system further includes a gas recovery device located at the end of the pipeline and connected in parallel with the exhaust passage. If gas recovery is required after forming, the exhaust valve is not opened, but the switching pneumatic valve is opened to allow the gas to enter the gas recovery device for subsequent processing and reuse.

[0013] In a preferred embodiment of the refractory metal ultra-high temperature vacuum superplastic forming equipment of the present invention: the vacuum system includes a backing pump, an intermediate Roots pump, and a diffusion pump; the intermediate Roots pump is disposed above the backing pump, and the diffusion pump is disposed above the intermediate Roots pump.

[0014] In a preferred embodiment of the refractory metal ultra-high temperature vacuum superplastic forming equipment of the present invention: the argon gas circulation rapid cooling system includes an air inlet and an air outlet; the air inlet is located at the upper end of the heating furnace cavity, and the air outlet is located on the side of the heating furnace cavity.

[0015] The present invention also provides a method.

[0016] In a preferred embodiment of the method described in this invention: a method comprising the aforementioned refractory metal ultra-high temperature vacuum superplastic forming equipment, further comprising the following steps: coating the surface of the refractory alloy billet with a high-temperature lubricant and then placing it in a superplastic forming mold and positioning it; fixing the upper mold and the lower mold in a pressure loading system; activating the vacuum system and evacuating the vacuum degree inside the heating system to 1×10⁻⁶. -3 Below Pa; start the heating system and control the vacuum level at 5 × 10⁻⁶ during the heating process. -2 Below Pa, the refractory alloy billet is heated to the superplastic forming temperature and held at that temperature by independently adjusting the temperature of each zone; the pressure loading system is controlled to close the mold until the upper and lower molds come into contact and a clamping force is applied; the ultra-high temperature air expansion system is activated to air-expand the billet using high-pressure inert gas, while simultaneously applying a clamping force. The clamping force ,in, The gas pressure to be filled into the mold cavity, Let be the projected area of ​​the surface. This is the clamping force coefficient; after molding is completed, the molding air pressure is vented until it is below 0.05MPa, then the molded part is removed.

[0017] In a preferred embodiment of the method described in this invention, the clamping force coefficient k is 1.2 to 1.5.

[0018] The beneficial effects of this invention are as follows: The ultra-high temperature vacuum superplastic forming equipment and method for refractory metals proposed in this invention overcome the processing difficulties caused by the high melting point, high hardness and room temperature brittleness of alloys such as tungsten and molybdenum. It can integrate the manufacturing of complex curved surfaces, thin walls, deep holes and hollow conformal flow channel structures that are difficult to process by traditional methods, so that their performance advantages in high temperature environment can be fully utilized in aerospace, nuclear industry and other fields, and the formed parts can achieve near-complete density. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein: Figure 1 A front view of the present invention is shown.

[0020] Figure 2 A left view of the present invention is shown.

[0021] Figure 3 A schematic diagram of the ultra-high temperature gas expansion system of the present invention is shown.

[0022] In the picture, 1-Pressure loading system, 101-Bearing bed, 102-Upper loading platform, 103-Lower loading platform; 2-Heating system, 201-Heating furnace cavity, 202-Insulation layer, 203-Water-cooled heating electrode, 204-Heating rod; 3-Ultra-high temperature gas expansion system, 301-Gas source device, 302-Filter, 303-Pressure regulator, 304-Ball valve, 305-Electronic regulator, 306-Buffer tank, 307-Electronic pressure gauge, 308-Pneumatic valve, 309-Upper platform pneumatic valve, 310-Lower platform pneumatic valve, 311-Exhaust valve, 312-Vacuum valve, 313-Vacuum gauge, 314-Vacuum pump, 315-High temperature connector, 316-High temperature graphite gas pipe, 317-High temperature sealing assembly, 318-Gas recovery pipeline, 319-Gas recovery device, 320-Gas heating device, 321-Inlet temperature measuring device, and 322-Switching pneumatic valve; 4-Vacuum system, 401-Backing pump, 402-Intermediate Roots pump, 403-Diffusion pump; 5 - Argon gas circulation rapid cooling system, 501 - Air inlet, 502 - Air outlet; 6-Control system; 701 - Upper mold, 702 - Lower mold. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0024] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0025] Example 1, referring to Figures 1-3This embodiment provides an ultra-high temperature vacuum superplastic forming equipment for refractory metals, including: a pressure loading system 1; a heating system 2 disposed inside the pressure loading system 1; an ultra-high temperature gas expansion system 3 connected to the heating system 2; a vacuum system 4 located outside the heating system 2; and an argon gas circulation rapid cooling system 5 disposed outside the heating system 2.

[0026] As one embodiment provided in this application, such as Figure 1 The pressure loading system 1 includes a support bed 101, which is a column type or a frame type; an upper loading platform 102 located above the support bed 101, and a lower loading platform 103 located below the support bed 101; the upper loading platform 102 and the lower loading platform 103 provide superplastic forming pressure through hydraulic drive.

[0027] As one embodiment provided in this application, such as Figure 1 The heating system 2 includes a heating furnace cavity 201, which is a double-layered hollow structure with a built-in bottom-inlet and top-outlet water-cooling channel. Circulating cooling water provides cooling protection for the heating furnace cavity 201. A graphite insulation layer 202 is placed on the inner surface of the heating furnace cavity 201. The graphite insulation layer 202 has a multi-layered structure: the outermost layer is a soft graphite felt layer, the middle layer is a hard graphite felt layer, and the innermost layer is a hard, dense graphite plate. This multi-layered structure provides excellent insulation, preventing the furnace cavity surface temperature from becoming too high. Water-cooled heating electrodes 203 and graphite heating rods 204 are also installed on the heating furnace cavity 201. One end of the water-cooled heating electrode 203 is connected to a low-voltage heating power supply, and the other end passes through the heating furnace cavity 201 and connects to the graphite heating rods 204. The graphite heating rods 204 are arranged in a ring, with gaps between them ranging from 30 to 100 mm depending on their diameter.

[0028] As one embodiment provided in this application, such as Figure 3 The ultra-high temperature gas expansion system 3 includes a gas source device 301; a filter 302 located downstream of the gas source device 301, used to remove water and oil from the high-pressure gas, thus playing a purification role; a pressure regulator 303 located at the output end of the filter 302; and a ball valve 304 located at the output end of the pressure regulator 303. After the purified high-pressure gas is reduced to the set outlet safety gas pressure by the pressure regulator 303, it is manually controlled to open and close by the ball valve 304, which can prevent subsequent failures from causing system damage and play a protective role.

[0029] The ultra-high temperature gas expansion system 3 also includes an electronic regulator 305 and an electronic pressure gauge 307 located downstream of the electronic regulator 305, which is used to monitor the intake pressure in real time and feed it back to the electronic regulator 305. Through the built-in PID program, it automatically adjusts to ensure that the deviation between the intake pressure and the set pressure is stable within 0.1% MPa. The buffer tank 306 located between the electronic regulator 305 and the electronic pressure gauge 307 can reduce gas pulsation, reduce system pressure fluctuations, and improve the reliability and durability of the pipeline.

[0030] Downstream of the electronic pressure gauge 307, a main pneumatic valve 308 is also provided for automatically controlling the on / off of superplastic inert gas. The main pneumatic valve 308 is connected in parallel with the upper platform pneumatic valve 309, the lower platform pneumatic valve 310, and the vacuum valve 312. According to the forming requirements of the superplastic forming mold, the upper mold 701 or the lower mold 702 is selected for air expansion forming.

[0031] The ultra-high temperature gas expansion system 3 also includes a vacuum gauge 313 and a vacuum pump 314 located downstream of the vacuum valve 312 for negative pressure forming and venting the gas inside the mold cavity before forming. At the same time, a vacuum gauge is set in front of the vacuum pump to monitor the negative pressure of the mold and ensure that the gas pressure inside the cavity is <100Pa.

[0032] A high-temperature connector 315 is provided downstream of the pneumatic valve 309 on the upper platform, and a graphite high-temperature gas pipe 316 is provided downstream of the high-temperature connector 315. The graphite high-temperature gas pipe 316 is connected to the upper mold 701 or the lower mold 702 via a high-temperature sealing assembly 317. A gas heating device 320 is installed on the high-temperature graphite gas pipe 316 section outside the furnace cavity. Specifically, it uses an induction coil to surround the high-temperature gas pipe 316 to heat the cold, high-pressure inert gas before it enters the furnace cavity. An inlet temperature measuring device 321 is also provided to monitor the temperature of the heated gas in real time.

[0033] The exhaust valve 311 is located at the end of the ultra-high temperature gas expansion system 3 to vent the gas after molding and ensure that the gas pressure inside the molding mold cavity is less than 0.05MPa, which is a safe demolding pressure.

[0034] The gas recovery device 319 is located at the end of the pipeline and is connected in parallel with the exhaust passage. If gas recovery is required after molding, the exhaust valve 311 is not opened, but the switching pneumatic valve 322 is opened to allow the gas to enter the gas recovery device 319 for subsequent processing and reuse.

[0035] During superplastic gas expansion molding, the gas source device 301 is turned on. High-pressure inert gas passes through filter 302 to remove water and oil impurities. Afterward, it is reduced to the set initial pressure value by pressure regulator 303. Ball valve 304 is opened, and electronic regulator 305 reads the pressure-time (PT) curve set in the system. Based on the curve, the gas pressure is regulated. Gas enters buffer tank 306 to reduce gas pulsation and system pressure fluctuations, making the system operate more smoothly. Electronic pressure gauge 307 monitors the gas pressure and provides real-time feedback to electronic regulator 305. Through PID control, the gas pressure fluctuation is ensured to remain stable within 0.1% MPa. Within a range, open the main pneumatic valve 308. Select either the upper platform pneumatic valve 309 or the lower platform pneumatic valve 310 according to the mold forming method. The gas then flows through the gas heating device 320 and is heated. Its temperature is monitored by the inlet temperature measuring device 321. Superplastic expansion is performed on the part. The superplastic gas pressure is based on the PT curve set by the system. After forming is completed, close the main pneumatic valve 308. If gas recovery is required, open the switching pneumatic valve 322 to allow the gas to enter the gas recovery device 319; if not, open the exhaust valve 311 to release the forming gas pressure. Exhausting ends when the gas pressure is below 0.05MPa. Open the mold and remove the formed part. Open the upper mold 701 and the lower mold 702 to remove the formed part.

[0036] The superplastic forming system has an independent vacuuming function, mainly for molds that require negative pressure forming. Before negative pressure forming, the main pneumatic valve 308 is closed, the vacuum valve 312 and the vacuum pump 314 are opened, the upper mold 701 and the lower mold 702 are selected, and the corresponding upper platform pneumatic valve 309 or lower platform pneumatic valve 310 is opened to evacuate the forming chamber of the mold. The vacuum gauge 313 monitors the vacuum degree of the forming chamber in real time, and the vacuum degree is stable within 100Pa.

[0037] As one embodiment provided in this application, such as Figure 2 Vacuum system 4 includes a backing pump 401, an intermediate Roots pump 402, and a diffusion pump 403; the intermediate Roots pump 402 is positioned above the backing pump 401, and the diffusion pump 403 is positioned above the intermediate Roots pump 402. The working vacuum level is stabilized at 10. -3 Pa, meets the vacuum requirements for high-temperature material forming, and prevents oxidation during the forming process of parts in high-temperature environments.

[0038] As one embodiment provided in this application, such as Figure 1 The argon gas circulation rapid cooling system 5 includes an air inlet 501 and an air outlet 502; the air inlet 501 is located at the upper end of the heating furnace cavity 201, and the air outlet 502 is located on the side of the heating furnace cavity 201, ensuring that argon gas can circulate rapidly inside, accelerating the cooling process of the workpiece, improving production efficiency and reducing the risk of part deformation.

[0039] Example 2: This example provides a method comprising the following steps: S1. After coating the surface of the refractory alloy billet with a high-temperature lubricant, place it in the superplastic forming mold and position it. Fix the upper mold 701 and the lower mold 702 in the pressure loading system 1.

[0040] Specifically, prepare a refractory alloy billet and a set of superplastic forming molds (including an upper mold 701 and a lower mold 702), fix the upper mold 701 and the lower mold 702 on the upper loading platform 102 and the lower loading platform 103, coat the surface of the billet with a high-temperature lubricant, place it in the superplastic forming mold, and position it.

[0041] S2. Start vacuum system 4 and evacuate the vacuum level inside heating system 2 to 1×10⁻⁶. -3 Below Pa.

[0042] S3. Start heating system 2, and control the vacuum level at 5×10 during the heating process. -2 Below Pa, the refractory alloy billet is heated to the superplastic forming temperature and held at that temperature by independently adjusting the temperature of each zone.

[0043] Specifically, a heating curve is set, heating system 2 is started, and the vacuum level is maintained at 5×10 during the heating process. - 2 If the vacuum level is below 5 × 10 Pa, then the vacuum level is below 5 × 10 Pa. -2 Pa stops heating. During the heating process, the heating power of each zone is independently adjusted to control the temperature uniformity within the furnace cavity within ±20℃. The billet is heated to the superplastic forming temperature and held at this temperature, which is 1550~1650℃ for molybdenum alloys and 1800~2000℃ for tungsten alloys. During the holding process, the heating power of each zone is continuously adjusted independently to control the temperature uniformity within the furnace cavity within ±10℃.

[0044] S4. Control the movement of the pressure loading system 1 to close the mold until the upper mold 701 and the lower mold 702 come into contact and apply the clamping force.

[0045] S5. Activate the ultra-high temperature air expansion system 3 to air-expand and form the billet using high-pressure inert gas, while simultaneously applying clamping force. The clamping force ,in, The gas pressure to be filled into the mold cavity, Let be the projected area of ​​the surface. This is the clamping force coefficient.

[0046] Specifically, when the gas source device 301 is turned on, the high-pressure inert gas passes through the filter 302 to remove water and oil impurities, and then passes through the pressure regulator 303 to reduce the pressure to the set initial gas pressure value. The ball valve 304 is then opened, and the electronic regulator 305 reads the pressure-time set in the system (P). g The pressure is regulated according to the -T curve. The gas enters the buffer tank for pressure stabilization. The electronic pressure gauge monitors the gas pressure and provides real-time feedback to the electronic regulator 305. Through PID regulation, the pressure fluctuation is ensured to be stable within 0.1% MPa. The main pneumatic valve 308 is opened to perform superplastic bulging on the parts. The superplastic pressure is based on the P set by the system. g The loading process is performed using the -T curve, and a corresponding clamping force is applied simultaneously. The clamping force coefficient is between 1.2 and 1.5, and in this embodiment, it is set to 1.3. During this step, the vacuum level of the equipment needs to be monitored in real time. If the vacuum level changes abruptly, it indicates a gas leak. The safety valve must be closed immediately, and the vacuum pump 314 connected to the mold cavity must be started promptly to quickly vent the gas in the cavity and prevent excessively high gas pressure from damaging the vacuum pump 314.

[0047] S6. Exhausting and removing parts: After forming is completed, close the pneumatic valve. If gas needs to be recovered, introduce it into the gas recovery device. Otherwise, open the exhaust valve to release the forming gas pressure. You can choose to start the argon circulation rapid cooling system to quickly cool the formed workpiece. After the mold cavity gas pressure is lower than 0.05MPa, open the mold and remove the formed part.

[0048] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A high-temperature vacuum superplastic forming equipment for refractory metals, characterized in that: include, Pressure loading system (1); Heating system (2) installed inside the pressure loading system (1); The ultra-high temperature air expansion system (3) is connected to the heating system (2); A vacuum system (4) located outside the heating system (2), and; An argon gas circulation rapid cooling system (5) is installed outside the heating system (2).

2. The refractory metal ultra-high temperature vacuum superplastic forming equipment according to claim 1, characterized in that: The pressure loading system (1) includes a support bed (101); An upper loading platform (102) located above the supporting bed (101), and; The lower loading platform (103) is located below the bearing bed (101).

3. The refractory metal ultra-high temperature vacuum superplastic forming equipment according to claim 2, characterized in that: The heating system (2) includes a heating furnace chamber (201); A graphite insulation layer (202) is placed on the inner surface of the heating furnace cavity (201); and, Water-cooled heating electrodes (203) and graphite heating rods (204) are installed on the heating furnace cavity (201).

4. The refractory metal ultra-high temperature vacuum superplastic forming equipment according to claim 3, characterized in that: The ultra-high temperature gas expansion system (3) includes a gas source device (301), a filter (302) located downstream of the gas source device (301), a pressure regulator (303) located at the output end of the filter (302), and a ball valve (304) located at the output end of the pressure regulator (303).

5. The refractory metal ultra-high temperature vacuum superplastic forming equipment according to claim 4, characterized in that: The ultra-high temperature gas expansion system (3) also includes an electronic regulator (305), an electronic pressure gauge (307) located downstream of the electronic regulator (305), and a buffer tank (306) located between the electronic regulator (305) and the electronic pressure gauge (307). A main pneumatic valve (308) is also provided downstream of the electronic pressure gauge (307). The main pneumatic valve (308) is connected in parallel with the upper platform pneumatic valve (309), the lower platform pneumatic valve (310), and the vacuum valve (312).

6. The refractory metal ultra-high temperature vacuum superplastic forming equipment according to claim 5, characterized in that: The ultra-high temperature gas expansion system (3) also includes a vacuum gauge (313) and a vacuum pump (314) located downstream of the vacuum valve (312). A high-temperature connector (315) is provided downstream of the upper platform pneumatic valve (309), and a graphite high-temperature gas pipe (316) is provided downstream of the high-temperature connector (315). The graphite high-temperature gas pipe (316) is connected to the forming mold downstream via a high-temperature sealing component (317), which is located between the graphite high-temperature gas pipe (316) and the forming mold. The graphite high-temperature gas pipe (316) is surrounded by a gas heating device (320) for heating the cold high-pressure inert gas before it enters the furnace chamber, and is equipped with an inlet temperature measuring device (321) to monitor the temperature of the heated gas in real time. The ultra-high temperature gas expansion system (3) is equipped with a gas recovery device (319) at the end, and the gas enters the gas recovery device (319) by switching the pneumatic valve (322).

7. The exhaust valve (311) is located at the end of the ultra-high temperature gas expansion system (3).

8. The ultra-high temperature vacuum superplastic forming equipment for refractory metals according to claim 6, characterized in that: The vacuum system (4) includes a back pump (401), an intermediate Roots pump (402), and a diffusion pump (403). An intermediate Roots pump (402) is disposed above the fore-pump (401), and a diffusion pump (403) is disposed above the intermediate Roots pump (402).

9. The ultra-high temperature vacuum superplastic forming equipment for refractory metals according to claim 7, characterized in that: The argon gas circulation rapid cooling system (5) includes an air inlet (501) and an air outlet (502). The air inlet (501) is located at the upper end of the heating furnace cavity (201), and the air outlet (502) is located on the side of the heating furnace cavity (201).

10. A method, characterized in that: The equipment for ultra-high temperature vacuum superplastic forming of refractory metals according to any one of claims 1 to 8 further includes the following steps: After coating the surface of the refractory alloy billet with a high-temperature lubricant, it is placed in a superplastic forming mold and positioned. The upper mold and the lower mold are fixed in the pressure loading system (1). Start the vacuum system (4) and evacuate the vacuum level inside the heating system (2) to 1×10⁻⁶. -3 Below Pa; Start the heating system (2), and control the vacuum degree at 5×10 during the heating process. -2 Below Pa, the refractory alloy billet is heated to the superplastic forming temperature and held at that temperature by independently adjusting the temperature of each zone; The pressure loading system (1) is controlled to move to close the mold until the upper mold (701) and the lower mold (702) come into contact and a clamping force is applied; The ultra-high temperature gas expansion system (3) is activated to gas expand and form the billet using high-pressure inert gas, while simultaneously applying clamping force. The clamping force ,in, The gas pressure to be filled into the mold cavity, Let be the projected area of ​​the surface. This is the clamping force coefficient; After forming is completed, if gas recovery is required, introduce it into the gas recovery device; otherwise, open the exhaust valve to release the forming gas pressure. You can choose to start the argon circulation rapid cooling system to quickly cool the formed workpiece until it is below 0.05 MPa, then remove the formed workpiece.

11. The method according to claim 9, characterized in that: The clamping force coefficient k is 1.2~1.5.

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