A method for preparing molybdenum-rhenium alloy tube by spinning

Abstract

The present invention relates to the technical field of molybdenum-rhenium alloy tube spinning preparation, and discloses a molybdenum-rhenium alloy tube spinning preparation method, comprising the following steps: raw material preparation, selecting purity molybdenum powder and rhenium powder, weighing according to the rhenium content of 10%-30%, placing in a three-dimensional mixer, vacuuming and stirring to mix the powders; blank molding, mixing the powder into a rubber mold, cold isostatic pressing and holding pressure for 10-30 minutes to obtain a blank, the equipment has pressure feedback adjustment, the mold is coated with a high-temperature resistant release agent, adopts a double-layer structure, and is reinforced with an inner rubber layer and an outer metal layer; sintering treatment, the blank is placed in a vacuum sintering furnace, first heated to 1200-1500℃ and kept warm for 1-3 hours, then kept warm for 2-6 hours, and a small amount of hydrogen can be passed in the later stage, and the furnace has temperature monitoring; pipe processing. The raw materials of the present invention are high-purity and fine-grained and evenly mixed; blank molding and sintering are precisely controlled to ensure quality; pipe processing and spinning are high-precision; post-processing optimizes structure, cleans surface, and properly packages to ensure high performance of the alloy tube and meet the needs of high-end fields.

Description

Technical Field

[0001] The invention relates to the technical field of spinning preparation of molybdenum-rhenium alloy tubes, in particular to a spinning preparation method of molybdenum-rhenium alloy tubes. Background Art

[0002] The demand for high-performance tubing is growing in many high-end sectors of modern industry, such as aerospace, nuclear energy, and electronics. Molybdenum-rhenium alloy tubing, thanks to molybdenum's high melting point, high strength, and excellent corrosion resistance, combined with rhenium's enhanced toughness and high-temperature performance, is an ideal material for these demanding applications.

[0003] However, the traditional molybdenum-rhenium alloy tube manufacturing process has many limitations and cannot meet the high standards required by current industrial development. In the early stages of raw material mixing, simple mechanical stirring was often used. Due to the fine particle size and certain viscosity of molybdenum and rhenium powders, conventional stirring is not only inefficient but also easily leads to powder agglomeration, resulting in uneven raw material mixing. This, in turn, can cause problems such as uneven billet density and composition segregation during the subsequent forming process, seriously affecting the mechanical properties and chemical stability of the alloy tube.

[0004] In terms of blank forming, the traditional compression molding process applies uneven pressure and cannot ensure that all parts of the blank reach the ideal relative density. It is prone to defects such as internal pores and cracks, and demolding is difficult, which often causes damage to the blank and reduces the product qualification rate.

[0005] The sintering process presents even more challenges. Conventional heating equipment is difficult to precisely control the heating rate, resulting in large temperature fluctuations. This can cause uneven alloy grain growth and structural instability in the alloy tube, leading to deformation, cracking, and other failures when used under high-temperature and high-pressure conditions. Furthermore, the lack of effective atmosphere control during the sintering process prevents oxidation of the billet, significantly compromising the purity and performance of the alloy tube.

[0006] When it comes to pipe processing, traditional turning processes cause tool wear to be rapid and have low processing accuracy, making it difficult to achieve high-precision control of the inner and outer diameters of pipes. This makes it impossible to meet the stringent requirements for pipe tolerances in precision components such as aircraft engine blade cooling channels and nuclear reactor fuel rod cladding.

[0007] In the spinning process, if there is a lack of precise control of the spinning parameters and real-time monitoring methods, it is easy to cause problems such as uneven wall thickness of the pipe and excessive ovality. In addition, the unreasonable heat distribution during the spinning process will aggravate the residual stress of the pipe and affect its service life.

[0008] In the post-processing process, incomplete pickling and a lack of effective surface cleaning methods leave impurities on the surface of the alloy tubes, which not only affects the appearance but also causes corrosion during subsequent use. The packaging is simple and cannot isolate the outside moisture and oxygen, causing the alloy tubes to oxidize and rust during storage and transportation, further reducing their performance. In summary, an innovative and fully optimized spinning method for molybdenum-rhenium alloy tubes is urgently needed to overcome these difficulties and promote the high-quality development of related industries. Summary of the Invention

[0009] (1) Technical problems solved

[0010] In view of the shortcomings of the prior art, the present invention provides a method for spinning a molybdenum-rhenium alloy tube.

[0011] (2) Technical solution

[0012] A spinning preparation method for a molybdenum-rhenium alloy tube comprises the following steps: S1: raw material preparation: selecting molybdenum powder produced by a plasma atomization method, the particle size of which is normally distributed and concentrated in the range of 5-20 μm, and rhenium powder with a purity of not less than 99.9% obtained by electron beam melting and subsequent pulverization treatment, the particle size of which is 3-15 μm, and weighing the powder according to a rhenium content of 10%-30% by mass; placing the weighed powder in a three-dimensional mixer, the stirring blades inside the mixer having a double-layer spiral structure, the outer blades being responsible for quickly breaking up large agglomerates, and the inner blades for fine mixing, evacuating to 0.05-0.2 Pa, and stirring at a speed of 200-600 rpm for 2-6 hours;

[0013] S2: Blank forming: The mixed powder is loaded into a rubber mold made of fluororubber and formed by cold isostatic pressing with a pressure of 200-400 MPa and a holding time of 10-30 minutes. The pressure feedback adjustment system of the cold isostatic pressing equipment consists of a high-precision pressure sensor and an intelligent controller. A release agent is applied to the surface of the mold. The release agent is a high-temperature resistant, volatile, and residue-free silicone release agent with a coating thickness of 0.05-0.1 mm. The inner surface of the mold is evenly covered by atomized spraying to obtain a blank with a relative density of not less than 85%;

[0014] S3: Sintering treatment: The blank is placed in a vacuum sintering furnace. The heating element of the vacuum sintering furnace uses a graphite heating element. The temperature is first raised to 1200-1500℃ at a heating rate of 8-18℃ / min and kept at this temperature for 1-3 hours. During this stage, an infrared thermometer is used to monitor the surface temperature of the blank in real time, and the deviation from the set temperature is controlled within ±2℃; then the temperature is raised to 1800-2200℃ at a heating rate of 4-10℃ / min and kept at this temperature for 2-6 hours. The vacuum degree is maintained at 0.005-0.02Pa throughout the sintering process, and then the blank is cooled with the furnace. The sintering furnace is equipped with a temperature monitoring system with multiple thermocouples distributed at different positions to monitor the sintering temperature in real time;

[0015] S4: Pipe processing: The sintered blank is turned using carbide cutting tools with micro-nano coating treatment on the cutting edge. The coating material is TiAlN. The cutting speed is 50-150m / min, the feed rate is 0.1-0.5mm / rev, and the machining allowance is 1-3mm. The blank is processed into pipe fittings with an outer diameter tolerance within ±0.2mm and an inner diameter tolerance within ±0.1mm. The turning process is cooled by cutting fluid. The cutting fluid is a water-based cutting fluid with good lubrication and cooling properties. The cutting fluid is sprayed into the cutting area through a high-pressure spray system.

[0016] S5: Spinning process: The pipe is installed on the core mold of the spinning machine using strong spinning or flow spinning. The core mold is made of high-strength alloy steel and is nitrided to a surface hardness of HV900-HV1200. The core mold speed is 200-600 rpm, the spinning wheel feed speed is 0.5-2mm / s, and the spinning thinning rate is 20%-60%. The pipe is locally heated during the spinning process. The heating equipment is a high-frequency induction heating device with a heating temperature of 800-1200℃ and an induction heating frequency of 20-60kHz. The device is equipped with an intelligent power regulator to adjust the power in real time according to the material and size of the pipe. The spinning equipment is equipped with a force sensor to monitor the spinning pressure in real time.

[0017] S6: Post-processing process: Annealing treatment is performed on the molybdenum-rhenium alloy tube after spinning. The annealing furnace is a vacuum annealing furnace. Graphite felt is used as insulation material in the furnace. The annealing temperature is 1000-1500℃ and the insulation time is 1-3 hours. High-purity argon is introduced into the annealing furnace as a protective gas. The argon flow rate is 5-15L / min. The argon flow rate is accurately controlled by a gas mass flow controller. After annealing, pickling treatment is performed. The pickling solution is a mixed solution of hydrofluoric acid and nitric acid. The solution is placed in an acid- and alkali-resistant polytetrafluoroethylene container. The concentration of hydrofluoric acid is 3%-8%, and the concentration of nitric acid is 8%-15%. The pickling time is 10-30 minutes. The pickling process is carried out with the assistance of ultrasonic oscillation to remove surface impurities. Finally, it is blown dry and packaged.

[0018] Furthermore, in step S1, an ultrasonic vibration device is installed inside the three-dimensional mixer with an ultrasonic frequency of 30-60kHz. During the stirring process, it is turned on for 10-20 minutes every 30-60 minutes. The transducer of the ultrasonic vibration device is made of piezoelectric ceramic material with high energy conversion efficiency, and the vibration head is spherical with a large contact area with the powder.

[0019] Furthermore, in step S2, the cold isostatic pressing mold adopts a double-layer structure, with the inner layer being made of rubber and the outer layer being a metal reinforcement layer. The thickness of the metal reinforcement layer is 5-15 mm. The metal reinforcement layer is made of stainless steel and is tightly bonded to the inner layer through welding to enhance the mold's pressure resistance. The mold is demolded using hydraulic demolding, and the demolding force is controlled at 10-30 kN. The hydraulic demolding system consists of a hydraulic pump, a hydraulic cylinder, and a precision overflow valve, which can accurately control the size of the demolding force.

[0020] Furthermore, in step S3, the vacuum sintering furnace is equipped with an atmosphere adjustment system, and a small amount of hydrogen can be introduced in the later stage of sintering. The hydrogen flow rate is 1-3L / min. The atmosphere adjustment system consists of a gas cylinder, a precision flow control valve and a gas mixing device. The reducing property of hydrogen is used to remove trace oxide impurities that may exist inside the blank.

[0021] Furthermore, in step S4, the turning processing equipment uses a CNC lathe, and the CNC system has an automatic compensation function. The CNC system uses a Siemens 840D system. When the outer diameter or inner diameter tolerance is detected to be out of the set range during the turning process, the cutting parameters are automatically adjusted through the built-in PID algorithm.

[0022] Furthermore, in step S5, the dimensions of the tube are monitored in real time during the spinning process using a laser measuring instrument with a measurement accuracy of ±0.05 mm. The laser measuring instrument uses a helium-neon laser and adjusts the spinning wheel feed speed and core mold speed in real time according to the measurement results.

[0023] Furthermore, in step S6, ultrasonic cleaning is performed after the pickling treatment, with an ultrasonic frequency of 20-40 kHz and a cleaning time of 5-15 minutes. The ultrasonic cleaning equipment uses a stainless steel water tank with multiple ultrasonic transducers installed at the bottom, distributed in an array, to further remove tiny impurities on the surface.

[0024] Furthermore, in step S6, vacuum packaging is used for packaging, and a multi-layer composite aluminum foil bag is selected as the packaging material. The multi-layer composite aluminum foil bag consists of a three-layer structure, with an inner layer of polyethylene film, a middle layer of aluminum foil, and an outer layer of a nylon woven layer. It has high barrier properties and corrosion resistance, and can effectively isolate external moisture and oxygen. The vacuum packaging equipment uses a vacuum heat sealing machine with a heat sealing temperature of 150-200°C and a heat sealing time of 3-5 seconds.

[0025] (3) Beneficial technical effects

[0026] During the raw material preparation stage, advanced powder making technology is used to ensure the high purity and appropriate particle size of molybdenum powder and rhenium powder. Combined with the fine structure and ultrasonic vibration of the three-dimensional mixer, the powder mixing is highly uniform, effectively avoiding agglomeration and segregation, laying a solid foundation for subsequent processes and ensuring the stable composition and consistent performance of the alloy tube.

[0027] When the blank is formed, the cold isostatic pressing process is combined with a high-precision pressure feedback system and a special mold to apply uniform pressure, which can stably obtain high-quality blanks with a relative density of not less than 85%. Demolding is smooth and lossless, greatly improving the product qualification rate.

[0028] The sintering process ensures uniform growth of alloy grains, stable organizational structure and high purity of billets by means of precise heating rate control, reliable temperature monitoring and atmosphere adjustment, which greatly enhances the alloy tube's resistance to deformation and cracking in high temperature and high pressure environments.

[0029] In the pipe processing process, carbide tool coating and optimized cutting parameters, combined with high-pressure spray cooling, significantly improve processing accuracy. The inner and outer diameter tolerances of pipe fittings are strictly controlled, perfectly meeting the needs of high-end precision components.

[0030] During the spinning process, the core mold and spinning wheel parameters are precisely controlled, and real-time dimension monitoring and induction heating intelligent temperature control are used to achieve uniform wall thickness and ovality that meets the standards. Reasonable heat distribution reduces residual stress and extends the service life of the alloy tube.

[0031] The post-processing process is also excellent. Vacuum annealing combined with precise argon protection optimizes the internal structure; pickling and ultrasonic cleaning thoroughly remove impurities and improve surface quality; vacuum packaging is combined with high-performance multi-layer composite aluminum foil bags to isolate external corrosion, ensuring the long-term storage and transportation performance of the alloy tube, and promoting the widespread and reliable application of molybdenum-rhenium alloy tubes in high-end fields in all aspects. DETAILED DESCRIPTION

[0032] Example 1:

[0033] Raw materials preparation:

[0034] Molybdenum powder with a purity of 99.95% and a particle size of 8-15 μm, produced by the plasma rotating electrode method, and rhenium powder with a purity of 99.93% and a particle size of 5-10 μm, obtained by electron beam refining and airflow milling, were used. The powders were accurately weighed to a rhenium content of 20%. The powders were placed in a three-dimensional mixer equipped with an asymmetric double-layer helical structure, with a large outer pitch for rapid dispersion and a small inner pitch for fine mixing. The mixture was vacuumed to 0.1 Pa and stirred at 400 rpm for 4 hours. During this period, 45 kHz ultrasonic vibration was applied for 15 minutes every 45 minutes.

[0035] Blank forming:

[0036] The mixed powder is placed in a fluororubber mold and cold isostatically pressed at 300 MPa for 20 minutes. The pressure sensor accuracy of the cold isostatic press is ±0.05 MPa, and the intelligent controller is used for real-time calibration. The mold is then coated with a 0.08mm thick silicone release agent using an atomized spray method, resulting in a blank with a relative density of 88%. The mold has a two-layer structure, with a 10mm inner layer of fluororubber and an 8mm outer layer of stainless steel reinforcement.

[0037] Sintering treatment:

[0038] The billet is placed in a vacuum sintering furnace, heated by a graphite heating element, initially at a rate of 12°C / minute to 1350°C, controlled by an infrared thermometer with a tolerance of ±1.5°C, and held for two hours. The temperature is then raised at a rate of 6°C / minute to 2000°C and held for four hours. The vacuum is 0.01 Pa, monitored by multiple thermocouples with a tolerance of ±3°C. Hydrogen is then introduced at 2 L / min, controlled by a gas cylinder and a precision flow valve.

[0039] Pipe processing:

[0040] The sintered blanks were turned with carbide tools coated with 3μm TiAlN coating, cutting speed 100m / min, feed 0.3mm / rev, machining allowance 2mm, and high-pressure spraying 0.3MPa water-based cutting fluid to obtain pipes with outer diameter tolerance ±0.15mm and inner diameter tolerance ±0.08mm.

[0041] Spinning process:

[0042] The high-pressure spinning mandrel for pipe fittings is made of nitrided alloy steel with a surface hardness of HV1000, a rotation speed of 400 rpm, a spinning wheel feed of 1 mm / s, a thinning rate of 40%, high-frequency induction heating at 40 kHz to 1000°C, an intelligent power regulator for temperature control, and a piezoelectric force sensor (accuracy ±5%) for monitoring the spinning force.

[0043] Post-processing process:

[0044] The spun tubes were placed in a vacuum annealing furnace, insulated with graphite felt, and annealed at 1200°C for 2 hours under a protective atmosphere of 5-15 L / min high-purity argon (controlled by a mass flow controller). Acid washing was performed using a mixture of 5% hydrofluoric acid and 12% nitric acid in a polytetrafluoroethylene container under 15kHz ultrasonic vibration for 20 minutes, followed by 30kHz ultrasonic cleaning for 10 minutes. The tubes were then vacuum-packed in multi-layer composite aluminum foil bags and heat-sealed at 180°C for 3 seconds.

[0045] After testing, the density uniformity deviation of the alloy tube is less than 0.4%, the wall thickness uniformity deviation is less than 3%, and the room temperature tensile strength exceeds 800MPa, meeting the requirements of aviation engine hot end components.

[0046] Example 2:

[0047] Raw materials preparation:

[0048] Select 99.92% pure molybdenum powder (particle size 6-18 μm, plasma atomized) and 99.94% rhenium powder (particle size 4-12 μm, electron beam smelting and pulverization), weighed to a rhenium content of 25%. Use a three-dimensional mixer with staggered double-layer paddles, vacuum at 0.15 Pa, stirring at 300 rpm for 5 hours, and ultrasonically mixing for 10 minutes every 60 minutes at a frequency of 50 kHz.

[0049] Blank forming:

[0050] The mixed powder is put into the fluororubber mold, cold isostatically pressed at 350MPa and maintained for 15 minutes, the pressure sensor is ±0.1MPa, the mold is coated with 0.06mm release agent, hydraulic demolding is 20kN, the inner layer of the mold is 8mm fluororubber and the outer layer is 10mm stainless steel.

[0051] Sintering treatment:

[0052] The vacuum sintering furnace was heated at 10°C / min to 1400°C, kept warm for 1.5 hours, then to 2100°C at 8°C / min, kept warm for 3 hours, with a vacuum degree of 0.015 Pa and a temperature deviation of ±4°C. Hydrogen was passed at 1.5 L / min in the later stage.

[0053] Pipe processing:

[0054] Coated carbide tool for turning, cutting speed 80m / min, feed 0.2mm / rev, allowance 1.5mm, 0.4MPa cutting fluid spray, pipe tolerance: outer diameter ±0.18mm, inner diameter ±0.1mm.

[0055] Spinning process:

[0056] Flow spinning, core die speed 500 rpm, spinner feed 1.5 mm / s, thinning rate 30%, induction heating 50 kHz to 900 °C, spinning monitoring is the same as Example 1.

[0057] Post-processing process:

[0058] Annealing at 1300°C for 1.5 hours, argon 8-12 L / min, pickling with 6% hydrofluoric acid and 10% nitric acid, ultrasonication at 12 kHz for 25 minutes and 25 kHz for 12 minutes, and vacuum packaging parameters are the same as in Example 1.

[0059] The test results show that the density deviation of the alloy tube is less than 0.5%, the wall thickness deviation is less than 4%, and the high-temperature endurance strength is excellent, making it suitable for nuclear reactor cooling tubes.

[0060] Comparative Example:

[0061] Traditional preparation method:

[0062] The raw materials are mechanically stirred and mixed with molybdenum powder (99% purity, 10-30μm particle size) and rhenium powder (99% purity, 8-20μm particle size), roughly weighed to 15% rhenium. No vacuum or ultrasonic treatment is used. Molding is performed at 200MPa using ordinary steel molds, ensuring that the blank is not easily damaged during demolding. The sintering furnace heats up arbitrarily, lacks atmosphere control, and inaccurate insulation. The turning tools are mediocre, resulting in low machining precision. Spinning lacks real-time monitoring. Pickling involves a short soak in a single acid, followed by natural drying and simple packaging.

[0063]

[0064]

[0065] Performance test results:

[0066] The alloy tube has uneven density, with a deviation of more than 5%, uneven wall thickness of more than 10%, poor mechanical properties, low tensile strength, easy deformation and cracking at high temperatures, many surface impurities, and easy oxidation during storage, which is in sharp contrast to the examples.

[0067] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a molybdenum-rhenium alloy tube by spinning, characterized in that: The following steps are involved: S1: Raw material preparation: Molybdenum powder produced by plasma atomization method, with a normal particle size distribution concentrated in the range of 5-20μm, and rhenium powder with a purity of not less than 99.9% obtained by electron beam melting and crushing, with a particle size of 3-15μm, are selected and weighed according to a rhenium content of 10%-30% by mass; the weighed powders are placed in a three-dimensional mixer with a double-layer spiral structure of stirring blades. The outer blades are responsible for quickly breaking up large agglomerates, while the inner blades are responsible for fine mixing. The mixture is vacuumed to 0.05-0.2Pa and stirred at a speed of 200-600 rpm for 2-6 hours; S2: Blank forming: The mixed powder is loaded into a rubber mold made of fluororubber and formed by cold isostatic pressing with a pressure of 200-400 MPa and a holding time of 10-30 minutes. The pressure feedback adjustment system of the cold isostatic pressing equipment consists of a high-precision pressure sensor and an intelligent controller. A release agent is applied to the surface of the mold. The release agent is a high-temperature resistant, volatile, and residue-free silicone release agent with a coating thickness of 0.05-0.1 mm. The inner surface of the mold is evenly covered by atomized spraying to obtain a blank with a relative density of not less than 85%; S3: Sintering treatment: The blank is placed in a vacuum sintering furnace. The heating element of the vacuum sintering furnace uses a graphite heating element. The temperature is first raised to 1200-1500℃ at a heating rate of 8-18℃ / min and kept at this temperature for 1-3 hours. During this stage, an infrared thermometer is used to monitor the surface temperature of the blank in real time, and the deviation from the set temperature is controlled within ±2℃; then the temperature is raised to 1800-2200℃ at a heating rate of 4-10℃ / min and kept at this temperature for 2-6 hours. The vacuum degree is maintained at 0.005-0.02Pa throughout the sintering process, and then the blank is cooled with the furnace. The sintering furnace is equipped with a temperature monitoring system with multiple thermocouples distributed at different positions to monitor the sintering temperature in real time; S4: Pipe processing: The sintered blank is turned using carbide cutting tools with micro-nano coating treatment on the cutting edge. The coating material is TiAlN. The cutting speed is 50-150m / min, the feed rate is 0.1-0.5mm / rev, and the machining allowance is 1-3mm. The blank is processed into pipe fittings with an outer diameter tolerance within ±0.2mm and an inner diameter tolerance within ±0.1mm. The turning process is cooled by cutting fluid. The cutting fluid is a water-based cutting fluid with good lubrication and cooling properties. The cutting fluid is sprayed into the cutting area through a high-pressure spray system. S5: Spinning process: The pipe is installed on the core mold of the spinning machine using strong spinning or flow spinning. The core mold is made of high-strength alloy steel and is nitrided to a surface hardness of HV900-HV1200. The core mold speed is 200-600 rpm, the spinning wheel feed speed is 0.5-2mm / s, and the spinning thinning rate is 20%-60%. The pipe is locally heated during the spinning process. The heating equipment is a high-frequency induction heating device with a heating temperature of 800-1200℃ and an induction heating frequency of 20-60kHz. The device is equipped with an intelligent power regulator to adjust the power in real time according to the material and size of the pipe. The spinning equipment is equipped with a force sensor to monitor the spinning pressure in real time. S6: Post-processing process: Annealing treatment is performed on the molybdenum-rhenium alloy tube after spinning. The annealing furnace is a vacuum annealing furnace. Graphite felt is used as insulation material in the furnace. The annealing temperature is 1000-1500℃ and the insulation time is 1-3 hours. High-purity argon is introduced into the annealing furnace as a protective gas. The argon flow rate is 5-15L / min. The argon flow rate is accurately controlled by a gas mass flow controller. After annealing, pickling treatment is performed. The pickling solution is a mixed solution of hydrofluoric acid and nitric acid. The solution is placed in an acid- and alkali-resistant polytetrafluoroethylene container. The concentration of hydrofluoric acid is 3%-8%, and the concentration of nitric acid is 8%-15%. The pickling time is 10-30 minutes. The pickling process is carried out with the assistance of ultrasonic oscillation to remove surface impurities. Finally, it is blown dry and packaged.

2. The method for preparing a molybdenum-rhenium alloy tube by spinning according to claim 1, wherein: In step S1, an ultrasonic vibration device is installed inside the three-dimensional mixer with an ultrasonic frequency of 30-60kHz. During the stirring process, it is turned on for 10-20 minutes every 30-60 minutes. The transducer of the ultrasonic vibration device is made of piezoelectric ceramic material with high energy conversion efficiency. The vibration head is spherical and has a large contact area with the powder.

3. The method for preparing a molybdenum-rhenium alloy tube by spinning according to claim 1, wherein: In step S2, the cold isostatic pressing mold adopts a double-layer structure, with the inner layer made of rubber and the outer layer being a metal reinforcement layer. The thickness of the metal reinforcement layer is 5-15mm. The metal reinforcement layer is made of stainless steel and is tightly bonded to the inner layer through welding to enhance the mold's pressure resistance. The mold is demolded by hydraulic demolding, and the demolding force is controlled at 10-30kN. The hydraulic demolding system consists of a hydraulic pump, a hydraulic cylinder and a precision overflow valve, which can accurately control the size of the demolding force.

4. The method for preparing a molybdenum-rhenium alloy tube by spinning according to claim 1, wherein: In step S3, the vacuum sintering furnace is equipped with an atmosphere control system. A small amount of hydrogen can be introduced in the later stage of sintering. The hydrogen flow rate is 1-3L / min. The atmosphere control system consists of a gas cylinder, a precision flow control valve and a gas mixing device. The reducing property of hydrogen is used to remove trace oxide impurities that may exist inside the blank.

5. The method for preparing a molybdenum-rhenium alloy tube by spinning according to claim 1, wherein: In step S4, the turning processing equipment uses a CNC lathe, and the CNC system has an automatic compensation function. The CNC system uses the Siemens 840D system. When the outer diameter or inner diameter tolerance is detected to be out of the set range during the turning process, the cutting parameters are automatically adjusted through the built-in PID algorithm.

6. The method for preparing a molybdenum-rhenium alloy tube by spinning according to claim 1, wherein: In step S5, the dimensions of the tube are monitored in real time during the spinning process using a laser measuring instrument with a measurement accuracy of ±0.05 mm. The laser measuring instrument uses a helium-neon laser and adjusts the spinning wheel feed speed and core mold speed in real time based on the measurement results.

7. The method for preparing a molybdenum-rhenium alloy tube by spinning according to claim 1, wherein: In step S6, ultrasonic cleaning is performed after the pickling treatment. The ultrasonic frequency is 20-40kHz and the cleaning time is 5-15 minutes. The ultrasonic cleaning equipment uses a stainless steel water tank with multiple ultrasonic transducers installed at the bottom in an array distribution to further remove tiny impurities on the surface.

8. The method for preparing a molybdenum-rhenium alloy tube by spinning according to claim 1, wherein: In step S6, vacuum packaging is used for packaging, and the packaging material is a multi-layer composite aluminum foil bag. The multi-layer composite aluminum foil bag consists of a three-layer structure, with an inner layer of polyethylene film, a middle layer of aluminum foil, and an outer layer of nylon woven layer. It has high barrier properties and corrosion resistance, and can effectively isolate external moisture and oxygen. The vacuum packaging equipment uses a vacuum heat sealing machine with a heat sealing temperature of 150-200°C and a heat sealing time of 3-5 seconds.

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