A tungsten-rhenium alloy powder mixing method for controlling shrinkage during double-layer metal composite sintering

Abstract

A tungsten-rhenium alloy powder mixing method for controlling the shrinkage rate during double-layer metal composite sintering relates to the technical field of preparation of target materials for medical CT tubes. The present invention mixes W-Re powders prepared by wet chemical method and solid-liquid mixing in different proportions, and explores the influence of different powder mixing ratios on the shrinkage rate through pre-sintering and sintering processes, thereby meeting the requirements of composite sintering for different shrinkage rates, and measures the sintering density. The results show that as the powder mixing composition continues to change, the sintering density of different powder mixing ratios also changes. As the proportion of tungsten-rhenium alloy powder prepared by wet chemical method continues to decrease, its linear shrinkage rate also gradually decreases, thereby meeting the requirements of the preparation industry for the shrinkage rate of tungsten-rhenium alloy.

Description

Technical Field

[0001] The invention relates to the technical field of medical CT machine tube target material preparation, and in particular to a tungsten-rhenium alloy powder mixing method for controlling the shrinkage rate during double-layer metal composite sintering. Background Art

[0002] CT (Computerized Tomography) has become an essential diagnostic tool in modern medicine. The performance of a CT machine depends largely on the quality of the X-ray tube. The anode target is a crucial component of the X-ray tube, directly affecting the X-ray emission intensity and tube life. When the X-ray tube is operating, the anode target is bombarded by a high-energy electron beam, emitting X-rays. However, the energy conversion efficiency is very low, only approximately 1%. Over 99% of the energy is converted into heat, with this heat primarily concentrated at the anode. In a vacuum environment, the temperature of the anode target can rise very high. It has been reported that the ambient temperature during X-ray tube operation is above 1300°C, with local temperatures reaching as high as 2600°C. Therefore, the material used for CT rotating anode targets requires high melting points, high heat capacity, low high-temperature vapor pressure, and excellent thermal shock resistance.

[0003] Tungsten has an extremely high elastic modulus (407 GPa at room temperature), a high melting point (3410°C), and high high-temperature strength. However, due to the intermittent operation of X-ray tubes, which alternate between hot and cold, the target surface material is prone to cracking. Tungsten is notch-sensitive, which can easily lead to crack propagation and deepening, and separation from the substrate. This crack propagation and deepening exposes the substrate material to electron beam bombardment, generating X-rays of unwanted wavelengths and damaging the X-ray tube. To improve the overall performance of pure tungsten, a small amount of rhenium is added to tungsten. Rhenium and tungsten have similar atomic numbers and physical and chemical properties, making it easier to form an infinite solid solution. The addition of rhenium reduces the Peierls stress of tungsten's plastic deformation, thereby improving its plastic toughness. Due to the solid solution strengthening and toughening mechanisms caused by the addition of rhenium, tungsten as a target material greatly improves the target surface's resistance to electron bombardment, effectively reduces the dose decay rate, and reduces pure notch sensitivity, greatly extending the target disk's service life.

[0004] Currently, the tube targets for medical CT machines are generally made from a combination of bimetallic materials: one part is made from molybdenum-zirconium-titanium alloy (TZM), and the other part is made from W-10 (wt%) Re powder. During sintering, the target disc cannot simultaneously meet the density requirements of W-10 (wt%) Re and TZM. Typically, the TZM is ensured to reach a high density, while the W-10 (wt%) Re reaches a certain density, and the density is subsequently increased through plastic deformation. Furthermore, the sintering activity of the powder and the properties of the green body have a combined impact on the bonding performance of the W-10 (wt%) Re and TZM layers during sintering. However, W-10 (wt%) Re powder prepared by a single method has been associated with cracking during use. This is primarily due to the different shrinkage rates of the dissimilar metals during sintering. The shrinkage rate of the TZM layer during sintering is typically 0.16-0.2. This difference in shrinkage between the W-10 (wt%) Re powder and the TZM layer leads to cracking during target preparation. In this paper, the W-10 (wt%) Re powder prepared by wet chemical method and the W-10 (wt%) Re powder prepared by solid-liquid mixing are mixed in different proportions to control the linear shrinkage of the green body, and at the same time obtain a green body with a higher sintering density to solve the cracking problem occurring during composite sintering. Summary of the Invention

[0005] The present invention mixes W-10 (wt%) Re powder prepared by a wet chemical method and W-10 (wt%) Re powder prepared by solid-liquid mixing in different proportions, and explores the influence of different powder mixing ratios on the shrinkage rate through pre-sintering and sintering processes, thereby meeting the requirements of composite sintering for different shrinkage rates, and measures the sintering density. Regulating the shrinkage rate of W-10 (wt%) Re powder by a powder mixing method is a method for regulating the shrinkage of the green body with high efficiency and simple process. The present invention achieves the purpose of controlling the shrinkage rate of the green body by mixing W-10 (wt%) Re powder prepared by a wet chemical method and W-10 (wt%) Re powder prepared by solid-liquid mixing in different proportions.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is:

[0007] A tungsten-rhenium alloy powder mixing method for controlling the shrinkage rate during double-layer metal composite sintering, comprising the following steps:

[0008] Step 1: Preparation of tungsten-rhenium precursor by wet chemical method

[0009] First, add ammonium metatungstate powder into deionized water until fully dissolved, and place the solution in a magnetic stirrer for heating. Adjust the rotor to an appropriate speed and raise the temperature to 100-120°C. After the temperature stabilizes, add ammonium rhenate to the solution. After the ammonium rhenate is fully stirred and dissolved, add oxalic acid. After the oxalic acid is completely dissolved, stabilize the temperature at 100-120°C and allow the solution to react for 3-5 hours. After the solute reaction is complete, a tungsten-rhenium precursor solution is obtained. The solid content of the precursor solution is 25%-32%.

[0010] Step 2: Spray drying the tungsten-rhenium precursor solution prepared in step 1

[0011] The working parameters of the spray drying equipment are set. The spray drying starts heating and the inlet air temperature is raised to 200-230°C. After the outlet air temperature stabilizes, the feed port and the tungsten-rhenium precursor solution are connected and the peristaltic pump is turned on. After the precursor solution is spray dried, the powder in the collection tank is collected to obtain the tungsten-rhenium precursor powder.

[0012] Step 3: Preparation of tungsten-rhenium precursor by solid-liquid mixing

[0013] A certain proportion of ammonium rhenate is dissolved in deionized water at elevated temperature, and then a certain proportion of pure tungsten powder is evenly added to the ammonium rhenate solution, requiring the tungsten powder to be completely immersed in the solution. The slurry of tungsten powder is then stirred and dried until all the water in the ammonium rhenate solution evaporates. After evaporation, the ammonium rhenate adheres to the surface of the tungsten powder particles in the form of fine particles, forming a preliminary pre-alloyed W-10 (wt%) Re precursor powder.

[0014] Step 4: Restore

[0015] The tungsten-rhenium precursor is spread flatly in a firing boat, and the firing boat is placed in a hydrogen reduction furnace. Hydrogen is introduced and then the temperature is raised to 1000-1100°C at 8-12°C / min, kept warm for 2-4 hours, and then reduced to 480-520°C at 8-12°C / min. The tungsten-rhenium alloy powder is obtained by cooling the tungsten-rhenium precursors prepared in steps 2 and 3 separately.

[0016] Step 5: Mix the powder

[0017] The tungsten-rhenium alloy prepared by the reduced solid-liquid method and the tungsten-rhenium alloy powder prepared by the reduced wet chemical method were mixed in different proportions, respectively:

[0018] 100% wet chemical tungsten-rhenium powder;

[0019] 75% wet chemical tungsten-rhenium powder and 25% solid-liquid mixed tungsten-rhenium powder;

[0020] 50% wet chemical tungsten-rhenium powder, 50% solid-liquid mixed tungsten-rhenium powder;

[0021] 25% wet chemical tungsten-rhenium powder, 75% solid-liquid mixed tungsten-rhenium powder;

[0022] Tungsten-rhenium powder prepared by 100% solid-liquid mixing;

[0023] The tungsten-rhenium alloy powder prepared by solid-liquid mixing and wet chemical method was placed in a powder mixer with the parameters set to a speed of 700 rpm / min and a mixing time of 2 h.

[0024] Step 6: Sintering

[0025] A mold filled with tungsten-rhenium alloy powder is placed in a tablet press, and a single-sided axial pressure of 650-700 MPa is applied to the mold and maintained for 1-2 minutes. The pressure is then released and the pressed block is taken out; the pressed block is pre-sintered in hydrogen and sintered in high-temperature argon to prepare tungsten-rhenium alloys with different mixed powder ratios.

[0026] As a preferred technical solution of the present invention, in the tungsten-rhenium alloy powder mixing method:

[0027] In the step 1, the added amounts of ammonium rhenate and oxalic acid are 11.94% and 0-38% of the mass of ammonium metatungstate, respectively.

[0028] The operating parameters of the spray drying equipment in step 2 are: inlet air temperature 200-230°C, outlet air temperature 100-120°C, atomizer speed 300-350r / min, and feed rate 1-2L / h.

[0029] The sintering step in step six is ​​as follows: first, the pressed block is pre-sintered in hydrogen, the block is laid flat in a sintering boat, and then the sintering boat is placed in an argon tube furnace, the argon tube furnace is vacuumed and argon is then introduced; the temperature is raised from room temperature to 1100°C at 5-10°C / min and held for 2 hours, then reduced to 480-520°C at 5-10°C / min, and then cooled to room temperature with the furnace to obtain a tungsten-rhenium alloy with a certain bonding strength; finally, the pre-sintered block is subjected to high-temperature argon sintering, the sintering boat with the block is placed in a graphite furnace, and then argon is introduced; then the temperature is raised to 2150°C at 10-15°C / min, held for 2 hours, reduced to 580-620°C at 10-15°C / min, and then cooled to room temperature with the furnace to obtain a tungsten-rhenium alloy.

[0030] Compared with the prior art, the beneficial effects of the present invention are mainly manifested in:

[0031] This study mixed tungsten-rhenium alloy powder prepared by wet chemical methods with tungsten-rhenium alloy powder prepared by solid-liquid mixing. By varying the ratio of the tungsten-rhenium alloy powders prepared by different methods, the researchers investigated changes in shrinkage before and after sintering to meet the application requirements of double-layer metal composite sintering. The results showed that as the powder mix composition varied, the sintered density varied with the different powder mix ratios. As the proportion of tungsten-rhenium alloy powder prepared by wet chemical methods decreased, its linear shrinkage also gradually decreased, thus meeting the shrinkage requirements of tungsten-rhenium alloys in the manufacturing industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 These are pre-sintered images of Examples 1, 2, 3, 4, and 5.

[0033] Figure 2 These are the sintered images of Examples 1, 2, 3, 4, and 5.

[0034] Figure 3 Metallographic microscope images of tungsten-rhenium alloys prepared in Examples 1, 2, 3, 4, and 5.

[0035] Figure 4 Statistical diagram of grain size of tungsten-rhenium alloy prepared in Examples 1, 2, 3, 4, and 5. DETAILED DESCRIPTION

[0036] The present invention is further described below in conjunction with embodiments and drawings.

[0037] Example 1

[0038] Step 1: Preparation of tungsten-rhenium precursor by wet chemical method

[0039] Dissolve a certain proportion of ammonium metatungstate (AMT, Aladdin, purity ≥99.95%), ammonium rhenate (NH4ReO4, purity ≥99.9%), and oxalic acid (C2H2O4·2H2O, analytical grade) in deionized water and stir thoroughly until the solution is clear and free of precipitate. First, add ammonium metatungstate powder to deionized water until fully dissolved. Heat the solution in a magnetic stirrer, adjust the rotor speed to an appropriate level, and raise the temperature to 120°C. Once the temperature stabilizes, add ammonium rhenate to the solution. After the ammonium rhenate has been thoroughly stirred and dissolved, add oxalic acid. Once the oxalic acid is completely dissolved, stabilize the temperature at 120°C and allow the solution to react for 4 hours. Once the solute reaction is complete, a tungsten-rhenium precursor solution is obtained, with a solids content of 25%-32%.

[0040] In step 1, the added amounts of ammonium rhenate and oxalic acid are 11.94% and 20% of the mass of ammonium metatungstate, respectively.

[0041] Step 2: Spray drying the tungsten-rhenium precursor solution prepared in step 1

[0042] The operating parameters of the spray drying equipment were set to 220°C inlet air temperature, 110°C outlet air temperature, 300 r / min atomizer speed, and 1.5 L / h feed rate. The spray dryer began heating and raised the inlet air temperature to 220°C. After the outlet air temperature stabilized, the feed port was connected to the tungsten-rhenium precursor solution and the peristaltic pump was turned on. After the precursor solution was spray-dried, the powder was collected in a collection tank to obtain the tungsten-rhenium precursor powder.

[0043] Step 3: Restore

[0044] The tungsten-rhenium precursor was spread flat in the firing boat, and then the firing boat was placed in the hydrogen reduction furnace, and then hydrogen (hydrogen purity ≥ 99.999%, hydrogen flow rate 2m 3 / h) to ensure that there is no gas other than hydrogen in the tube furnace cavity, then heat it to 1100℃ at 10℃ / min, keep it for 3h, then cool it to 520℃ at 10℃ / min, and then cool it to room temperature with the furnace to obtain tungsten-rhenium alloy powder.

[0045] Step 4: Sintering

[0046] The mold containing the tungsten-rhenium alloy powder is placed in a tablet press. A single-side axial pressure of 700 MPa is applied to the mold and maintained for 1 minute. The pressure is then released and the pressed block is taken out. The pressed block is pre-sintered in hydrogen and the block is spread flat in a sintering boat. The sintering boat is then placed in an argon tube furnace. The argon tube furnace is vacuumed and then argon is introduced (argon purity ≥ 99.999%, argon flow rate 2m 3 / h). The temperature was raised from room temperature to 1100℃ at 10℃ / min and kept for 2h, then dropped to 520℃ at 10℃ / min, and then cooled to room temperature with the furnace to obtain a tungsten-rhenium alloy with a certain bonding strength. Finally, the pre-sintered block was sintered at high temperature in argon. The sintering boat with the block was placed in a graphite furnace, and then argon was introduced (argon purity ≥99.999%, argon flow rate 8m 3 The temperature was then raised to 2150°C at a rate of 10°C / min, held for 2 hours, and then lowered to 600°C at a rate of 10°C / min. The mixture was then cooled to room temperature to obtain a tungsten-rhenium alloy (the powder mixing ratio was 100% wet chemical method to prepare tungsten-rhenium powder).

[0047] Example 2:

[0048] Step 1: Preparation of tungsten-rhenium precursor by wet chemical method

[0049] Dissolve a certain proportion of ammonium metatungstate (AMT, Aladdin, purity ≥99.95%), ammonium rhenate (NH4ReO4, purity ≥99.9%), and oxalic acid (C2H2O4·2H2O, analytical grade) in deionized water and stir thoroughly until the solution is clear and free of precipitate. First, add ammonium metatungstate powder to deionized water until fully dissolved. Heat the solution in a magnetic stirrer, adjust the rotor speed to an appropriate level, and raise the temperature to 120°C. Once the temperature stabilizes, add ammonium rhenate to the solution. After the ammonium rhenate has been thoroughly stirred and dissolved, add oxalic acid. Once the oxalic acid is completely dissolved, stabilize the temperature at 120°C and allow the solution to react for 4 hours. Once the solute reaction is complete, a tungsten-rhenium precursor solution is obtained, with a solids content of 25%-32%.

[0050] In step 1, the added amounts of ammonium rhenate and oxalic acid are 11.94% and 20% of the mass of ammonium metatungstate, respectively.

[0051] Step 2: Preparation of tungsten-rhenium precursor by solid-liquid mixing

[0052] A certain proportion of ammonium rhenate (NH4ReO4, purity ≥99.9%) is dissolved in deionized water at 80°C. A certain proportion of pure tungsten powder is then evenly added to the ammonium rhenate solution, ensuring that the tungsten powder is completely immersed in the solution. The slurry is then dried while stirring until all the water in the ammonium rhenate solution evaporates. After evaporation, the ammonium rhenate adheres to the surface of the tungsten powder particles in the form of fine particles, forming a preliminary pre-alloyed W-10 (wt%) Re precursor powder.

[0053] Step 3: Spray drying the tungsten-rhenium precursor solution prepared in step 1

[0054] The operating parameters of the spray drying equipment were set to 220°C inlet air temperature, 110°C outlet air temperature, 300 r / min atomizer speed, and 1.5 L / h feed rate. The spray dryer began heating and raised the inlet air temperature to 220°C. After the outlet air temperature stabilized, the feed port was connected to the tungsten-rhenium precursor solution and the peristaltic pump was turned on. After the precursor solution was spray-dried, the powder was collected in a collection tank to obtain the tungsten-rhenium precursor powder.

[0055] Step 4: Restore

[0056] The tungsten-rhenium precursor was spread flat in the firing boat, and then the firing boat was placed in the hydrogen reduction furnace, and then hydrogen (hydrogen purity ≥ 99.999%, hydrogen flow rate 2m 3 / h) to ensure that there is no gas other than hydrogen in the tube furnace cavity, then heat it to 1100℃ at 10℃ / min, keep it for 3h, then cool it to 520℃ at 10℃ / min, and then cool it to room temperature with the furnace to obtain tungsten-rhenium alloy powder.

[0057] Step 5: Mix the powder

[0058] Weigh 15g of the wet chemically prepared tungsten-rhenium alloy powder and 5g of the solid-liquid mixed tungsten-rhenium alloy powder. Place them in a powder mixer set to a speed of 700 rpm / min and a mixing time of 12 hours.

[0059] Step 6: Sintering

[0060] The mold containing the tungsten-rhenium alloy powder is placed in a tablet press. A single-side axial pressure of 700 MPa is applied to the mold and maintained for 1 minute. The pressure is then released and the pressed block is taken out. The pressed block is pre-sintered in hydrogen and the block is spread flat in a sintering boat. The sintering boat is then placed in an argon tube furnace. The argon tube furnace is vacuumed and then argon is introduced (argon purity ≥ 99.999%, argon flow rate 2m 3 / h). The temperature was raised from room temperature to 1100℃ at 10℃ / min and kept for 2h, then dropped to 520℃ at 10℃ / min, and then cooled to room temperature with the furnace to obtain a tungsten-rhenium alloy with a certain bonding strength. Finally, the pre-sintered block was sintered at high temperature in argon. The sintering boat with the block was placed in a graphite furnace, and then argon was introduced (argon purity ≥99.999%, argon flow rate 8m 3 The temperature was then raised to 2150°C at a rate of 10°C / min, held for 2 hours, and then lowered to 600°C at a rate of 10°C / min. The mixture was then cooled to room temperature to obtain a tungsten-rhenium alloy (the powder mixing ratio was 75% tungsten-rhenium powder prepared by wet chemical method + 25% tungsten-rhenium powder prepared by solid-liquid mixing).

[0061] Example 3

[0062] The preparation steps are basically the same as those in Example 2, except that in step 5, 10 g of tungsten-rhenium alloy powder prepared by wet chemical method is weighed, and then 10 g of tungsten-rhenium alloy powder prepared by solid-liquid mixing is weighed. The final powder mixing ratio for preparing the tungsten-rhenium alloy is: 50% tungsten-rhenium powder prepared by wet chemical method + 50% tungsten-rhenium powder prepared by solid-liquid mixing.

[0063] Example 4:

[0064] The preparation steps are basically the same as those in Example 2, except that in step 5, 5 g of tungsten-rhenium alloy powder prepared by wet chemical method is weighed, and then 15 g of tungsten-rhenium alloy powder prepared by solid-liquid mixing is weighed. The final powder mixing ratio for preparing the tungsten-rhenium alloy is: 25% tungsten-rhenium powder prepared by wet chemical method + 75% tungsten-rhenium powder prepared by solid-liquid mixing.

[0065] Example 5:

[0066] Step 1: Preparation of tungsten-rhenium precursor by solid-liquid mixing

[0067] A certain proportion of ammonium rhenate (NH4ReO4, purity ≥99.9%) is dissolved in deionized water at 80°C. A certain proportion of pure tungsten powder is then evenly added to the ammonium rhenate solution, ensuring that the tungsten powder is completely immersed in the solution. The slurry is then dried while stirring until all the water in the ammonium rhenate solution evaporates. After evaporation, the ammonium rhenate adheres to the surface of the tungsten powder particles in the form of fine particles, forming a preliminary pre-alloyed W-10 (wt%) Re precursor powder.

[0068] Step 2: Restore

[0069] The tungsten-rhenium precursor was spread flat in the firing boat, and then the firing boat was placed in the hydrogen reduction furnace, and then hydrogen (hydrogen purity ≥ 99.999%, hydrogen flow rate 2m 3 / h) to ensure that there is no gas other than hydrogen in the tube furnace cavity, then heat it to 1100℃ at 10℃ / min, keep it for 3h, then cool it to 520℃ at 10℃ / min, and then cool it to room temperature with the furnace to obtain tungsten-rhenium alloy powder.

[0070] Step 3: Sintering

[0071] The mold containing the tungsten-rhenium alloy powder is placed in a tablet press. A single-side axial pressure of 700 MPa is applied to the mold and maintained for 1 minute. The pressure is then released and the pressed block is taken out. The pressed block is pre-sintered in hydrogen and the block is spread flat in a sintering boat. The sintering boat is then placed in an argon tube furnace. The argon tube furnace is vacuumed and then argon is introduced (argon purity ≥ 99.999%, argon flow rate 2m 3 / h). The temperature was raised from room temperature to 1100℃ at 10℃ / min and kept for 2h, then dropped to 520℃ at 10℃ / min, and then cooled to room temperature with the furnace to obtain a tungsten-rhenium alloy with a certain bonding strength. Finally, the pre-sintered block was sintered at high temperature in argon. The sintering boat with the block was placed in a graphite furnace, and then argon was introduced (argon purity ≥99.999%, argon flow rate 8m 3 / h). Then, the temperature was raised to 2150°C at 10°C / min, kept at that temperature for 2h, and then dropped to 600°C at 10°C / min. Then, the temperature was cooled to room temperature along with the furnace to obtain a tungsten-rhenium alloy (the powder mixing ratio was: 100% solid-liquid mixing to prepare tungsten-rhenium powder).

[0072] Table 1 Comparison of density and shrinkage before and after sintering of Examples 1, 2, 3, 4, and 5

[0073]

[0074] See also Figure 1-4As shown in Table 1, the present invention obtains W-10 (wt%) Re mixed powders by mixing W-10 (wt%) Re powder prepared by a wet chemical method and W-10 (wt%) Re powder prepared by a solid-liquid mixing method in different proportions. The mixed powders are briquetting and sintering to obtain tungsten-rhenium alloys prepared in Examples 1-5, and metallographic and linear shrinkage analysis is performed on these alloys.

[0075] The results show that as the proportion of tungsten-rhenium powder prepared by the wet chemical method increases, the density after sintering shows a trend of first increasing and then decreasing. When the mixed powder ratio reaches 75%, the density reaches a maximum value. The linear shrinkage rate of Example 2 after sintering is 0.2015. Compared with other embodiments, its linear shrinkage rate slightly exceeds the linear shrinkage rate range of the TZM layer after sintering (0.16-0.2), but its density after sintering is higher. Similarly, as the proportion of tungsten-rhenium alloy powder prepared by the solid-liquid mixing method increases, the grain size also increases first and then decreases. When the tungsten-rhenium alloy prepared by the wet chemical method accounts for 25%, the maximum average grain size appears. Therefore, the present invention obtains a higher sintering density while ensuring the shrinkage rate by adjusting the mixed powder ratio, thereby solving the cracking problem caused by the difference in shrinkage rate between the TZM layer and the tungsten-rhenium alloy during the composite sintering process.

[0076] The above content is merely an example and explanation of the concept of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A tungsten-rhenium alloy powder mixing method for controlling the shrinkage rate during double-layer metal composite sintering, characterized in that: Here are the steps: Step 1: Preparation of tungsten-rhenium precursor by wet chemical method First, add ammonium metatungstate powder into deionized water until fully dissolved, and place the solution in a magnetic stirrer for heating. Adjust the rotor to an appropriate speed and raise the temperature to 100-120°C. After the temperature stabilizes, add ammonium rhenate to the solution. After the ammonium rhenate is fully stirred and dissolved, add oxalic acid. After the oxalic acid is completely dissolved, stabilize the temperature at 100-120°C and allow the solution to react for 3-5 hours. After the solute reaction is complete, a tungsten-rhenium precursor solution is obtained. The solid content of the precursor solution is 25%-32%. Step 2: Spray drying the tungsten-rhenium precursor solution prepared in step 1 The working parameters of the spray drying equipment are set. The spray drying starts heating and the inlet air temperature is raised to 200-230°C. After the outlet air temperature stabilizes, the feed port and the tungsten-rhenium precursor solution are connected and the peristaltic pump is turned on. After the precursor solution is spray dried, the powder in the collection tank is collected to obtain the tungsten-rhenium precursor powder. Step 3: Preparation of tungsten-rhenium precursor by solid-liquid mixing A certain proportion of ammonium rhenate is dissolved in deionized water at elevated temperature, and then a certain proportion of pure tungsten powder is evenly added to the ammonium rhenate solution, requiring the tungsten powder to be completely immersed in the solution. The slurry of tungsten powder is then stirred and dried until all the water in the ammonium rhenate solution evaporates. After evaporation, the ammonium rhenate adheres to the surface of the tungsten powder particles in the form of fine particles, forming a preliminary pre-alloyed W-10 (wt%) Re precursor powder. Step 4: Restore The tungsten-rhenium precursor is spread flatly in a firing boat, and the firing boat is placed in a hydrogen reduction furnace. Hydrogen is introduced and then the temperature is raised to 1000-1100°C at 8-12°C / min, kept warm for 2-4 hours, and then reduced to 480-520°C at 8-12°C / min. The tungsten-rhenium alloy powder is obtained by cooling the tungsten-rhenium precursors prepared in steps 2 and 3 separately. Step 5: Mix the powder The tungsten-rhenium alloy prepared by the reduced solid-liquid method and the tungsten-rhenium alloy powder prepared by the reduced wet chemical method were mixed in different proportions, respectively: 100% wet chemical tungsten-rhenium powder; 75% wet chemical tungsten-rhenium powder and 25% solid-liquid mixed tungsten-rhenium powder; 50% wet chemical tungsten-rhenium powder, 50% solid-liquid mixed tungsten-rhenium powder; 25% wet chemical tungsten-rhenium powder, 75% solid-liquid mixed tungsten-rhenium powder; Tungsten-rhenium powder prepared by 100% solid-liquid mixing; The tungsten-rhenium alloy powder prepared by solid-liquid mixing and wet chemical method was placed in a powder mixer with the parameters set to a speed of 700 rpm / min and a mixing time of 2 h. Step 6: Sintering A mold filled with tungsten-rhenium alloy powder is placed in a tablet press, and a single-sided axial pressure of 650-700 MPa is applied to the mold and maintained for 1-2 minutes. The pressure is then released and the pressed block is taken out; the pressed block is pre-sintered in hydrogen and sintered in high-temperature argon to prepare tungsten-rhenium alloys with different mixed powder ratios.

2. The tungsten-rhenium alloy powder mixing method according to claim 1, wherein: In the step 1, the added amounts of ammonium rhenate and oxalic acid are 11.94% and 0-38% of the mass of ammonium metatungstate, respectively.

3. The tungsten-rhenium alloy powder mixing method according to claim 1, wherein: The operating parameters of the spray drying equipment in step 2 are: inlet air temperature 200-230°C, outlet air temperature 100-120°C, atomizer speed 300-350r / min, and feed rate 1-2L / h.

4. The tungsten-rhenium alloy powder mixing method according to claim 1, wherein: The sintering step in step six is: First, the pressed block is pre-sintered in hydrogen. The block is laid flat in a sintering boat, which is then placed in an argon tube furnace. The argon tube furnace is evacuated and then purged with argon. The temperature is raised from room temperature to 1100°C at a rate of 5-10°C / min and held for 2 hours. The temperature is then lowered to 480-520°C at a rate of 5-10°C / min and then cooled to room temperature in the furnace to obtain a tungsten-rhenium alloy with a certain bonding strength. Finally, the pre-sintered block is sintered at high temperature in argon. The sintering boat with the block is placed in a graphite furnace and then purged with argon. Then heat it to 2150℃ at 10-15℃ / min, keep it for 2h, reduce it to 580-620℃ at 10-15℃ / min, and then cool it to room temperature in the furnace to obtain tungsten-rhenium alloy.

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