High-uniformity tungsten-rhenium carbide pre-alloyed powder as well as preparation method and application thereof

Abstract

The invention provides high-uniformity tungsten-rhenium carbide pre-alloyed powder as well as a preparation method and application thereof, and belongs to the technical field of alloy materials. The preparation method of the tungsten-rhenium carbide pre-alloyed powder comprises the following steps that S1, a tungsten precursor, a rhenium precursor and an organic carbon source are weighed, mixed and dissolved in water, a precursor solution is obtained, and tungsten-rhenium-carbon precursor powder is obtained through spray drying; s2, carrying out heat preservation for 1-2 hours at the temperature of T1 DEG C in a hydrogen atmosphere; keeping the temperature for 3-4 hours at T2 DEG C in an inert gas atmosphere; t1 is less than T2; t1 DEG C is equal to 250 to 300 DEG C; t2 DEG C is equal to 300 to 400 DEG C; and S3, switching to a hydrogen atmosphere, carrying out heat preservation on a product obtained in the step S2 at 400-680 DEG C for 1-3 hours, and then carrying out heat preservation at 700-1100 DEG C for 1-6 hours. According to the method, combined calcination is conducted through the hydrogen and the inert atmosphere, the content of the rhenium element in the tungsten-rhenium carbide pre-alloyed powder can be further increased, and element distribution is uniform.

Description

Technical Field

[0001] This invention relates to the field of alloy materials technology, and in particular to a highly uniform tungsten-rhenium carbide pre-alloyed powder, its preparation method, and its application. Background Technology

[0002] Tungsten-rhenium carbide (W-Re-C) is widely used in aerospace structural components and high-end cutting tools due to its high melting point, excellent high-temperature strength, and thermal shock resistance. The addition of rhenium significantly improves the ductility and creep resistance of tungsten carbide. However, the traditional preparation of tungsten-rhenium carbide composite powders often involves mechanically mixing tungsten powder, rhenium powder, and a carbon source before high-temperature carbonization, which leads to problems such as component segregation and incomplete reactions. In particular, uneven distribution of rhenium in the powder can easily cause fluctuations in the alloy properties after sintering, becoming a bottleneck restricting its industrial application. Summary of the Invention

[0003] The purpose of this invention is to address the aforementioned deficiencies in the prior art by providing a highly uniform tungsten-rhenium carbide pre-alloyed powder and its preparation method.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: The first aspect of this application provides a method for preparing highly uniform tungsten-rhenium carbide pre-alloyed powder, comprising the following steps: S1: Weigh out tungsten precursor, rhenium precursor, and organic carbon source, mix and dissolve them in water to obtain a precursor solution. The precursor solution is spray-dried to obtain tungsten-rhenium-carbon precursor powder. S2: The tungsten-rhenium-carbon precursor powder obtained in step S1 is first kept at a temperature of 1-2 h in a hydrogen atmosphere at T1℃; then kept at a temperature of 3-4 h in an inert gas atmosphere at T2℃. Where T1 < T2; T1℃ = 250~300℃; T2℃ = 300~400℃; S3: Switch to hydrogen atmosphere, keep the product of step S2 at 400~680℃ for 1~3h, and then keep it at 700~1100℃ for 1~6h to obtain the highly uniform tungsten rhenium carbide pre-alloyed powder.

[0005] As an embodiment of the present invention, in step S1, the mass ratio of tungsten element in the tungsten precursor to rhenium element in the rhenium precursor is (70:30) to (97:3).

[0006] As an embodiment of the present invention, in step S1, the mass percentage of the organic carbon source is 3 to 10% based on the total mass of the tungsten precursor and the rhenium precursor.

[0007] In a preferred embodiment of the present invention, in step S1, the mass ratio of tungsten element in the tungsten precursor to rhenium element in the rhenium precursor is (70:30) to (80:20).

[0008] As an embodiment of the present invention, the tungsten precursor includes at least one of ammonium metatungstate and ammonium paratungstate.

[0009] As an embodiment of the present invention, the rhenium precursor includes ammonium rheniumate.

[0010] As an embodiment of the present invention, the organic carbon source includes at least one of glucose, fructose, sucrose, citric acid, lysine, histidine, and arginine.

[0011] As an embodiment of the present invention, the spray drying conditions are: oxygen content ≤2wt%, inlet air temperature 180~250℃, outlet air temperature 80~135℃, atomization pressure 0.2~0.5MPa, and fan frequency 20~50Hz.

[0012] As an embodiment of the present invention, the inert gas atmosphere described in step S2 includes at least one gas selected from helium, argon, and nitrogen.

[0013] As an embodiment of the present invention, the flow rates of hydrogen and inert gas in step S2 are independently 3~20 L / min.

[0014] As an embodiment of the present invention, the flow rate of hydrogen in step S3 is 3~20L / min.

[0015] In a second aspect, the present invention provides a highly uniform tungsten-rhenium carbide pre-alloyed powder, wherein the highly uniform tungsten-rhenium carbide pre-alloyed powder is prepared by the preparation method described in the first aspect of the present invention.

[0016] As an embodiment of the present invention, in the highly uniform tungsten-rhenium carbide pre-alloyed powder, the mass ratio of tungsten to rhenium is (70:30) to (97:3), and the mass percentage of carbon in the highly uniform tungsten-rhenium carbide pre-alloyed powder is 0.04 to 1%.

[0017] A third aspect of the present invention provides the application of the highly uniform tungsten-rhenium carbide pre-alloyed powder described in the second aspect of the present invention, wherein the highly uniform tungsten-rhenium carbide pre-alloyed powder described in the second aspect of the present invention is used to prepare high-temperature structural components and wear-resistant coatings.

[0018] Compared with the prior art, the beneficial effects of the present invention are: This invention utilizes a combination of hydrogen and an inert atmosphere for calcination, which not only lowers the calcination temperature and reduces the probability of component segregation and incomplete reaction, but also further increases the rhenium content in the tungsten-rhenium carbide pre-alloy powder, thereby improving the ductility and creep resistance of the pre-alloy. Attached Figure Description

[0019] Figure 1 This is a morphology image of the highly uniform tungsten-rhenium carbide pre-alloyed powder of Example 1 of the present invention under a scanning electron microscope (SEM).

[0020] Figure 2 The image shows the XRD pattern of the highly uniform tungsten-rhenium carbide pre-alloyed powder of Example 1 of the present invention (tungsten-rhenium element mass ratio W:Re=97:3). It can be seen from the figure that W and W2C phases exist in the tungsten-rhenium carbide pre-alloyed powder.

[0021] Figure 3 The image shows the XRD pattern of the highly uniform tungsten-rhenium carbide pre-alloyed powder of Example 4 of the present invention (tungsten-rhenium element mass ratio W:Re=75:25). It can be seen from the figure that W, W2C and Re3W phases exist in the tungsten-rhenium carbide pre-alloyed powder.

[0022] Figure 4 EDS elemental surface scan analysis of the highly uniform tungsten-rhenium carbide pre-alloyed powder of Example 1 of the present invention showed that it contained W and Re elements and that they were uniformly distributed.

[0023] Figure 5 EDS elemental surface scan analysis of the highly uniform tungsten-rhenium carbide pre-alloyed powder of Comparative Example 1 of the present invention showed that it contained W and Re elements, but the distribution was not uniform.

[0024] Figure 6 EDS elemental surface scan analysis of the highly uniform tungsten-rhenium carbide pre-alloyed powder of Comparative Example 2 of the present invention showed that it contained W and Re elements, but the distribution was not uniform.

[0025] Figure 7 EDS elemental surface scan analysis of the highly uniform tungsten-rhenium carbide pre-alloyed powder of Comparative Example 3 of the present invention showed that it contained W and Re elements, but the distribution was not uniform.

[0026] Figure 8 EDS elemental surface scan analysis of the highly uniform tungsten-rhenium carbide pre-alloyed powder of Comparative Example 4 of the present invention showed that it contained W and Re elements, but the distribution was not uniform. Detailed Implementation

[0027] To better illustrate the purpose, technical solution, and advantages of this invention, the invention will be further described below with reference to specific embodiments and accompanying drawings. However, the embodiments do not limit the invention in any way. Unless otherwise specified, the reagents, methods, and equipment used in this invention are conventional reagents, methods, and equipment in this technical field. Unless otherwise specified, all reagents and materials used in this invention are commercially available.

[0028] In this invention, the technical features described in an open-ended manner include both closed-ended technical solutions composed of the listed features and open-ended technical solutions that include the listed features.

[0029] In this invention, numerical ranges are involved. Unless otherwise specified, the numerical ranges are considered continuous and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to an integer, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are included.

[0030] Unless otherwise specified, all reagents or instruments used in this invention are commercially available products.

[0031] In a first aspect, the present invention provides a method for preparing highly uniform tungsten-rhenium carbide pre-alloyed powder, comprising the following steps: S1: Weigh out tungsten precursor, rhenium precursor, and organic carbon source, mix and dissolve them in water to obtain a precursor solution. The precursor solution is spray-dried to obtain tungsten-rhenium-carbon precursor powder. S2: The tungsten-rhenium-carbon precursor powder obtained in step S1 is first kept at a temperature of 1-2 h in a hydrogen atmosphere at T1℃; then kept at a temperature of 3-4 h in an inert gas atmosphere at T2℃. Where T1 < T2; T1℃ = 250~300℃; T2℃ = 300~400℃; S3: Switch to hydrogen atmosphere, keep the product of step S2 at 400~680℃ for 1~3h, and then keep it at 700~1100℃ for 1~6h to obtain the highly uniform tungsten rhenium carbide pre-alloyed powder.

[0032] In the preparation of a uniform tungsten-rhenium precursor, the present invention incorporates an organic carbon source in situ. That is, during the preparation of the tungsten-rhenium alloy, carbon elements are incorporated in situ, so that the carbon elements can uniformly coat or partially penetrate the surface of the tungsten-rhenium alloy.

[0033] The precursor mixture of the present invention is first calcined briefly at a low temperature in a hydrogen atmosphere, and part of the precursor decomposes to obtain a mixture of WO3 / ReO3 / Re / C; then, in an inert atmosphere, the temperature is increased to further calcine and decompose the remaining precursor, and the decomposition product of the precursor in the inert atmosphere is a mixture of WO3 / ReO3 / C; therefore, the product after calcination in two atmospheres is a mixture of WO3 / ReO3 / Re / C. The inventors of the present invention creatively discovered that when the precursor is first calcined in a hydrogen atmosphere, the product of the calcination and decomposition of the precursor also contains Re elemental: (1) the outer electron cloud of the Re atom can overlap and interact with the chemical bonds in the precursor molecule, which weakens the chemical bonds of the precursor molecule to a certain extent and promotes the decomposition of the precursor. (2) By precisely controlling the temperature and atmosphere, the diffusion coefficient of Re atoms was effectively adjusted. In the low-temperature calcination stage under hydrogen atmosphere, the lower temperature made the diffusion rate of atoms relatively slow. However, at this time, Re atoms began to interact with other atoms produced by the decomposition of precursors, laying the foundation for subsequent uniform distribution. In the high-temperature calcination stage under inert atmosphere, the increased temperature accelerated the diffusion rate of atoms. At the same time, the special atmosphere further optimized the interaction between Re atoms and other atoms, enabling Re atoms to be more uniformly distributed in the alloy system in a shorter time, thereby achieving a significant improvement in the uniformity of Re distribution in tungsten rhenium carbide pre-alloyed powder.

[0034] After the precursor is completely pyrolyzed at a relatively low temperature, it is further reduced in situ using carbothermal reduction during hydrogen reduction of tungsten-rhenium oxide to obtain a uniformly dispersed tungsten-rhenium carbide composite powder. This achieves atomic-level mixing of W / Re / C, avoiding diffusion control issues during subsequent sintering. The product after carbothermal reduction at 700~1100℃ is W / Re / W2C. When a higher amount of organic carbon source is added, a small amount of WC will be further generated, forming a W / Re / W2C / WC composite powder.

[0035] In some embodiments of the present invention, in step S1, the mass ratio of tungsten in the tungsten precursor to rhenium in the rhenium precursor is (70:30) to (97:3), more preferably (70:30) to (80:20). The addition of rhenium can significantly improve the ductility and creep resistance of tungsten carbides. Through improvements to the preparation process, the present invention, under the process conditions of the present invention, can prepare tungsten-rhenium carbide alloys with high rhenium content.

[0036] In some embodiments of the present invention, the mass concentration of the precursor (including tungsten precursor, rhenium precursor and organic carbon source) in the precursor solution in step S1 is 20-50%.

[0037] In some embodiments of the present invention, the tungsten precursor includes at least one of ammonium metatungstate and ammonium paratungstate.

[0038] In some embodiments of the present invention, the rhenium precursor comprises ammonium rheniumate.

[0039] In some embodiments of the present invention, the organic carbon source is preferably a water-soluble small organic molecule carbon source, specifically including at least one of glucose, fructose, sucrose, citric acid, lysine, histidine, and arginine.

[0040] In some embodiments of the present invention, the spray drying conditions are: oxygen content ≤ 2 wt%, inlet air temperature 180~250℃, outlet air temperature 80~135℃, atomization pressure 0.2~0.5 MPa, and fan frequency 20~50 Hz. A certain inert gas (such as nitrogen, argon, helium, etc.) is used to purge the oxygen in the spray dryer, ensuring that the oxygen content in the spray dryer is ≤ 2 wt%.

[0041] The pretreatment process of the precursor directly affects the efficiency of subsequent calcination, pyrolysis, hydrogen reduction, and carbonization reactions, as well as the structure and properties of the final alloy. The core of spray drying is to atomize the precursor solution into tiny droplets using a high-pressure atomizer. These droplets instantly evaporate moisture in a hot air environment. Due to the surface tension of the droplets, they naturally form near-spherical particles after drying. This morphology not only reduces particle agglomeration but also provides a uniform channel for gas diffusion (such as H2 and inert gases) during subsequent calcination, preventing incomplete local reactions.

[0042] In some embodiments of the present invention, the inert gas atmosphere described in step S2 includes at least one gas selected from helium, argon, and nitrogen.

[0043] In some embodiments of the present invention, the flow rates of hydrogen and inert gas in step S2 are independently 3 to 20 L / min.

[0044] In some embodiments of the present invention, the flow rate of hydrogen gas in step S3 is 3~20 L / min.

[0045] When the flow rate of the gas forming the corresponding gas atmosphere is within the appropriate range mentioned above, it can ensure sufficient reaction and control the particle size of the powder, improve the dispersion uniformity of each element in the alloy, and eliminate obvious component segregation areas.

[0046] In a second aspect, the present invention provides a highly uniform tungsten-rhenium carbide pre-alloyed powder, wherein the highly uniform tungsten-rhenium carbide pre-alloyed powder is prepared by the preparation method described in the first aspect of the present invention.

[0047] In some embodiments of the present invention, the mass ratio of tungsten (W) to rhenium (Re) in the highly uniform tungsten-rhenium carbide pre-alloyed powder is (70:30) to (97:3), and the mass percentage of carbon in the highly uniform tungsten-rhenium carbide pre-alloyed powder is 0.04 to 1%.

[0048] In some embodiments of the present invention, the particle size of the highly uniform tungsten-rhenium carbide pre-alloyed powder is 2~4 μm.

[0049] A third aspect of the present invention provides the application of the highly uniform tungsten-rhenium carbide pre-alloyed powder described in the second aspect of the present invention, wherein the highly uniform tungsten-rhenium carbide pre-alloyed powder described in the second aspect of the present invention is used to prepare high-temperature structural components and wear-resistant coatings.

[0050] The following are specific embodiments of the present invention.

[0051] Example 1 This embodiment provides a highly uniform tungsten-rhenium carbide pre-alloyed powder, wherein the mass ratio of tungsten to rhenium is W:Re = 97:3, and the C content is 0.03%. The preparation method includes the following steps: S1: According to the element design ratio, weigh out the tungsten precursor - ammonium metatungstate, the rhenium precursor - ammonium rhenium, and the organic carbon source - glucose, wherein glucose accounts for 3% of the total mass of the raw material powder; stir and mix the weighed precursor raw materials evenly, and then add them to water to fully dissolve them to obtain a precursor solution with a mass concentration of 50%. The above precursor solution was pumped into a spray dryer at a feed rate of 50 r / min. The inlet temperature was controlled at 200°C, the outlet temperature at 110°C, the pressure at 0.3 MPa, the fan frequency at 30 Hz, the oxygen content in the spray dryer chamber was below 2%, and the oxygen removal medium was nitrogen gas with a purity of 99.999%. After drying, tungsten rhenium carbon precursor powder was obtained. S2: The tungsten-rhenium-carbon precursor powder obtained in step S1 was first heated to 300℃ (T1) in a hydrogen atmosphere (hydrogen flow rate of 10 L / min) at a heating rate of 5℃ / min and held for 1 h; then the atmosphere was switched to nitrogen atmosphere (nitrogen flow rate of 10 L / min) and heated to 350℃ (T2) at a heating rate of 5℃ / min and held for 3.5 h. S3: Switch to hydrogen atmosphere (hydrogen flow rate is 10L / min). The product from step S2 is first kept at 600℃ for 2h, and then heated to 900℃ and kept at 900℃ for 5h to obtain the highly uniform tungsten rhenium carbide pre-alloyed powder.

[0052] Example 2 This embodiment provides a highly uniform tungsten-rhenium carbide pre-alloyed powder, wherein the mass ratio of tungsten to rhenium is W:Re = 70:30, and the C content is 0.15%. The preparation method includes the following steps: S1: According to the element design ratio, weigh out the tungsten precursor - ammonium metatungstate, the rhenium precursor - ammonium rheniumate and the organic carbon source - arginine, wherein glucose accounts for 4% of the total mass of the raw material powder; stir and mix the weighed precursor raw materials evenly, and then add them to water to fully dissolve them to obtain a precursor solution with a mass concentration of 20%; The above precursor solution was pumped into a spray dryer at a feed rate of 50 r / min. The inlet temperature was controlled at 200°C, the outlet temperature at 110°C, the pressure at 0.3 MPa, the fan frequency at 30 Hz, the oxygen content in the spray dryer chamber was below 2%, and the oxygen removal medium was nitrogen gas with a purity of 99.999%. After drying, tungsten rhenium carbon precursor powder was obtained. S2: The tungsten-rhenium-carbon precursor powder obtained in step S1 was first heated to 300℃ (T1) in a hydrogen atmosphere (hydrogen flow rate of 10 L / min) at a heating rate of 5℃ / min and held for 1 h; then the atmosphere was switched to nitrogen atmosphere (nitrogen flow rate of 10 L / min) and heated to 350℃ (T2) at a heating rate of 5℃ / min and held for 3.5 h. S3: Switch to hydrogen atmosphere (hydrogen flow rate is 10L / min). The product from step S2 is first kept at 600℃ for 2h, and then heated to 900℃ and kept at 900℃ for 5h to obtain the highly uniform tungsten rhenium carbide pre-alloyed powder.

[0053] Example 3 This embodiment provides a highly uniform tungsten-rhenium carbide pre-alloyed powder, wherein the mass ratio of tungsten to rhenium is W:Re = 80:20, and the C content is 0.45%. The preparation method includes the following steps: S1: According to the element design ratio, weigh out the tungsten precursor - ammonium metatungstate, the rhenium precursor - ammonium rheniumate and the organic carbon source - arginine, wherein glucose accounts for 6% of the total mass of the raw material powder; stir and mix the weighed precursor raw materials evenly, and then add them to water to fully dissolve them to obtain a precursor solution with a mass concentration of 40%; The above precursor solution was pumped into a spray dryer at a feed rate of 50 r / min. The inlet temperature was controlled at 200°C, the outlet temperature at 110°C, the pressure at 0.3 MPa, the fan frequency at 30 Hz, the oxygen content in the spray dryer chamber was below 2%, and the oxygen removal medium was nitrogen gas with a purity of 99.999%. After drying, tungsten rhenium carbon precursor powder was obtained. S2: The tungsten-rhenium-carbon precursor powder obtained in step S1 was first heated to 300℃ (T1) in a hydrogen atmosphere (hydrogen flow rate of 10 L / min) at a heating rate of 5℃ / min and held for 1 h; then the atmosphere was switched to nitrogen atmosphere (nitrogen flow rate of 10 L / min) and heated to 350℃ (T2) at a heating rate of 5℃ / min and held for 3.5 h. S3: Switch to hydrogen atmosphere (hydrogen flow rate is 10L / min). The product from step S2 is first kept at 600℃ for 2h, and then heated to 900℃ and kept at 900℃ for 5h to obtain the highly uniform tungsten rhenium carbide pre-alloyed powder.

[0054] Example 4 This embodiment provides a highly uniform tungsten-rhenium carbide pre-alloyed powder, wherein the mass ratio of tungsten to rhenium is W:Re = 75:25, and the C content is 0.08%. The preparation method includes the following steps: S1: According to the element design ratio, weigh out the tungsten precursor - ammonium metatungstate, the rhenium precursor - ammonium rheniumate and the organic carbon source - arginine, wherein glucose accounts for 4% of the total mass of the raw material powder; stir and mix the weighed precursor raw materials evenly, and then add them to water to fully dissolve them to obtain a precursor solution with a mass concentration of 30%; The above precursor solution was pumped into a spray dryer at a feed rate of 50 r / min. The inlet temperature was controlled at 200°C, the outlet temperature at 110°C, the pressure at 0.3 MPa, the fan frequency at 30 Hz, the oxygen content in the spray dryer chamber was below 2%, and the oxygen removal medium was nitrogen gas with a purity of 99.999%. After drying, tungsten rhenium carbon precursor powder was obtained. S2: The tungsten-rhenium-carbon precursor powder obtained in step S1 was first heated to 300℃ (T1) in a hydrogen atmosphere (hydrogen flow rate of 10 L / min) at a heating rate of 5℃ / min and held for 1 h; then the atmosphere was switched to nitrogen atmosphere (nitrogen flow rate of 10 L / min) and heated to 350℃ (T2) at a heating rate of 5℃ / min and held for 3.5 h. S3: Switch to hydrogen atmosphere (hydrogen flow rate is 10L / min). The product from step S2 is first kept at 600℃ for 2h, and then heated to 900℃ and kept at 900℃ for 5h to obtain the highly uniform tungsten rhenium carbide pre-alloyed powder.

[0055] Example 5 This embodiment provides a highly uniform tungsten-rhenium carbide pre-alloyed powder, wherein the mass ratio of tungsten to rhenium is W:Re = 70:30, and the C content is 0.22%. The preparation method includes the following steps: S1: According to the element design ratio, weigh out the tungsten precursor - ammonium metatungstate, the rhenium precursor - ammonium rheniumate and the organic carbon source - arginine, wherein glucose accounts for 4% of the total mass of the raw material powder; stir and mix the weighed precursor raw materials evenly, and then add them to water to fully dissolve them to obtain a precursor solution with a mass concentration of 20%; The above precursor solution was pumped into a spray dryer at a feed rate of 50 r / min. The inlet temperature was controlled at 200°C, the outlet temperature at 110°C, the pressure at 0.3 MPa, the fan frequency at 30 Hz, the oxygen content in the spray dryer chamber was below 2%, and the oxygen removal medium was nitrogen gas with a purity of 99.999%. After drying, tungsten rhenium carbon precursor powder was obtained. S2: The tungsten-rhenium-carbon precursor powder obtained in step S1 was first heated to 250℃ (T1) in a hydrogen atmosphere (hydrogen flow rate of 10 L / min) at a heating rate of 5℃ / min and held for 2 h; then the atmosphere was switched to nitrogen atmosphere (nitrogen flow rate of 10 L / min) and heated to 400℃ (T2) at a heating rate of 5℃ / min and held for 1 h. S3: Switch to hydrogen atmosphere (hydrogen flow rate is 10L / min). The product from step S2 is first kept at 600℃ for 2h, and then heated to 900℃ and kept at 900℃ for 5h to obtain the highly uniform tungsten rhenium carbide pre-alloyed powder.

[0056] Example 6 This embodiment provides a highly uniform tungsten-rhenium carbide pre-alloyed powder, wherein the mass ratio of tungsten to rhenium is W:Re = 70:30, and the C content is 0.18%. The preparation method includes the following steps: S1: According to the element design ratio, weigh out the tungsten precursor - ammonium metatungstate, the rhenium precursor - ammonium rheniumate and the organic carbon source - arginine, wherein glucose accounts for 4% of the total mass of the raw material powder; stir and mix the weighed precursor raw materials evenly, and then add them to water to fully dissolve them to obtain a precursor solution with a mass concentration of 20%; The above precursor solution was pumped into a spray dryer at a feed rate of 50 r / min. The inlet temperature was controlled at 200°C, the outlet temperature at 110°C, the pressure at 0.3 MPa, the fan frequency at 30 Hz, the oxygen content in the spray dryer chamber was below 2%, and the oxygen removal medium was nitrogen gas with a purity of 99.999%. After drying, tungsten rhenium carbon precursor powder was obtained. S2: The tungsten-rhenium-carbon precursor powder obtained in step S1 was first heated to 280℃ (T1) at a heating rate of 5℃ / min in a hydrogen atmosphere (hydrogen flow rate of 10L / min) and held for 1.5h; then the atmosphere was switched to nitrogen atmosphere (nitrogen flow rate of 10L / min) and heated to 300℃ (T2) at a heating rate of 5℃ / min and held for 6h. S3: Switch to hydrogen atmosphere (hydrogen flow rate is 10L / min). The product from step S2 is first kept at 600℃ for 2h, and then heated to 900℃ and kept at 900℃ for 5h to obtain the highly uniform tungsten rhenium carbide pre-alloyed powder.

[0057] Example 7 This embodiment provides a highly uniform tungsten-rhenium carbide pre-alloyed powder, wherein the mass ratio of tungsten to rhenium is W:Re = 70:30, and the C content is 0.19%. The preparation method includes the following steps: S1: According to the element design ratio, weigh out the tungsten precursor - ammonium metatungstate, the rhenium precursor - ammonium rheniumate and the organic carbon source - arginine, wherein glucose accounts for 4% of the total mass of the raw material powder; stir and mix the weighed precursor raw materials evenly, and then add them to water to fully dissolve them to obtain a precursor solution with a mass concentration of 20%; The above precursor solution was pumped into a spray dryer at a feed rate of 50 r / min. The inlet temperature was controlled at 200°C, the outlet temperature at 110°C, the pressure at 0.3 MPa, the fan frequency at 30 Hz, the oxygen content in the spray dryer chamber was below 2%, and the oxygen removal medium was nitrogen gas with a purity of 99.999%. After drying, tungsten rhenium carbon precursor powder was obtained. S2: The tungsten-rhenium-carbon precursor powder obtained in step S1 was first heated to 300℃ (T1) in a hydrogen atmosphere (hydrogen flow rate of 10 L / min) at a heating rate of 5℃ / min and held for 1 h; then the atmosphere was switched to nitrogen atmosphere (nitrogen flow rate of 10 L / min) and heated to 350℃ (T2) at a heating rate of 5℃ / min and held for 3.5 h. S3: Switch to hydrogen atmosphere (hydrogen flow rate is 10L / min). The product from step S2 is first kept at 600℃ for 1h, and then heated to 700℃ and kept at 700℃ for 6h to obtain the highly uniform tungsten rhenium carbide pre-alloyed powder.

[0058] Example 8 This embodiment provides a highly uniform tungsten-rhenium carbide pre-alloyed powder, wherein the mass ratio of tungsten to rhenium is W:Re = 70:30, and the C content is 0.13%. The preparation method includes the following steps: S1: According to the element design ratio, weigh out the tungsten precursor - ammonium metatungstate, the rhenium precursor - ammonium rheniumate and the organic carbon source - arginine, wherein glucose accounts for 4% of the total mass of the raw material powder; stir and mix the weighed precursor raw materials evenly, and then add them to water to fully dissolve them to obtain a precursor solution with a mass concentration of 20%; The above precursor solution was pumped into a spray dryer at a feed rate of 50 r / min. The inlet temperature was controlled at 200°C, the outlet temperature at 110°C, the pressure at 0.3 MPa, the fan frequency at 30 Hz, the oxygen content in the spray dryer chamber was below 2%, and the oxygen removal medium was nitrogen gas with a purity of 99.999%. After drying, tungsten rhenium carbon precursor powder was obtained. S2: The tungsten-rhenium-carbon precursor powder obtained in step S1 was first heated to 300℃ (T1) in a hydrogen atmosphere (hydrogen flow rate of 10 L / min) at a heating rate of 5℃ / min and held for 1 h; then the atmosphere was switched to nitrogen atmosphere (nitrogen flow rate of 10 L / min) and heated to 350℃ (T2) at a heating rate of 5℃ / min and held for 3.5 h. S3: Switch to hydrogen atmosphere (hydrogen flow rate is 10L / min). The product from step S2 is first kept at 400℃ for 3h, and then heated to 1100℃ and kept at 1h to obtain the highly uniform tungsten rhenium carbide pre-alloyed powder.

[0059] Comparative Example 1 This comparative example provides a tungsten-rhenium carbide pre-alloyed powder, which is prepared according to the method of Example 2. The difference from Example 2 is that in step S2, the temperature is raised to 350°C at a heating rate of 5°C / min under a nitrogen atmosphere (nitrogen flow rate of 10 L / min) and held for 4.5 h, and the precursor powder is not pre-pyrolyzed under a hydrogen atmosphere.

[0060] Comparative Example 2 This comparative example provides a tungsten-rhenium carbide pre-alloyed powder, which is prepared according to the method of Example 2. The difference from Example 2 is that in step S2, the precursor powder is heated to 300°C for 4.5 hours in a hydrogen atmosphere (hydrogen flow rate of 10 L / min) at a heating rate of 5°C / min, and is not switched to an inert atmosphere for pyrolysis.

[0061] Comparative Example 3 This comparative example provides a tungsten-rhenium carbide pre-alloyed powder, prepared according to the method of Example 2. The difference from Example 2 is that in step S2, pyrolysis is first carried out under a nitrogen atmosphere and then under a hydrogen atmosphere. Specifically, the temperature is first raised to 300°C at a heating rate of 5°C / min and held for 1 hour in a nitrogen atmosphere (nitrogen flow rate of 10 L / min); then the temperature is switched to a hydrogen atmosphere (hydrogen flow rate of 10 L / min) and raised to 350°C at a heating rate of 5°C / min and held for 3.5 hours.

[0062] Comparative Example 4 This comparative example provides a tungsten-rhenium carbide pre-alloyed powder, which is prepared according to the method of Example 2. The difference from Example 2 is that in step S2, the temperature is raised to 350°C at a heating rate of 5°C / min under a nitrogen atmosphere (nitrogen flow rate of 10 L / min) and held for 4.5 h; in step S3, the temperature is held at 1500°C for 7 h.

[0063] Performance testing The tungsten-rhenium carbide pre-alloyed powders prepared in the above examples and comparative examples were used as test samples, and their physical properties were characterized as follows. The test results are detailed in Table 1: 1. Morphological characteristics Tungsten-rhenium carbide pre-alloyed powder samples were bonded to conductive adhesive, and their spherical morphology could be observed under a scanning electron microscope (SEM). Example 1 is provided for details. Figure 1 The average particle size is recorded in Table 1. The average particle size is obtained from the SEM image by randomly selecting sample particles from five locations according to the "five-point sampling method". 20 sample particles are selected from each location, for a total of 100 sample particles for particle size testing. The average particle size of these 100 sample particles is then recorded as the particle size d of this batch of products. The specific test results are recorded in Table 1. 2. The composition of the tungsten-rhenium carbide pre-alloyed powders prepared in the above examples and comparative examples was analyzed using XRD. For example, Example 1 (with lower Re content) is detailed below. Figure 2 This indicates that the tungsten-rhenium carbide pre-alloyed powder includes W and W₂C phases. Due to the low Re content, the characteristic peaks of Re-containing elements in the XRD pattern are not significant. The XRD pattern of the highly uniform tungsten-rhenium carbide pre-alloyed powder in Example 4 (tungsten-rhenium mass ratio W:Re=75:25) is shown in [reference needed]. Figure 3 ),from Figure 3 It can be seen that W, W2C, and Re3W phases exist in the tungsten-rhenium carbide pre-alloyed powder; 3. Uniformity of element distribution Elemental surface scanning was performed using the EDS module in a scanning electron microscope (SEM), see [link to documentation]. Figures 4-8 ,in Figure 4 The elemental analysis surface scan of the tungsten-rhenium carbide pre-alloyed powder of Example 1 of the present invention shows that it contains W and Re elements and that they are uniformly distributed. Figures 5-8 The elemental analysis surface scans of the tungsten-rhenium carbide pre-alloyed powders of Comparative Examples 1, 2, 3, and 4 show that the distribution of W and Re elements is not uniform.

[0064] Table 1 The results above show that: This invention utilizes a combination of hydrogen and an inert atmosphere for calcination, which not only lowers the calcination temperature and reduces the probability of component segregation and incomplete reaction, but also further increases the rhenium content in the tungsten-rhenium carbide pre-alloy powder, thereby improving the ductility and creep resistance of the pre-alloy.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for preparing highly uniform tungsten-rhenium carbide pre-alloyed powder, characterized in that, Includes the following steps: S1: Weigh out tungsten precursor, rhenium precursor, and organic carbon source, mix and dissolve them in water to obtain a precursor solution. The precursor solution is spray-dried to obtain tungsten-rhenium-carbon precursor powder. S2: The tungsten-rhenium-carbon precursor powder obtained in step S1 is first kept at a temperature of 1-2 h in a hydrogen atmosphere at T1℃; then kept at a temperature of 3-4 h in an inert gas atmosphere at T2℃. Where T1 < T2; T1℃ = 250~300℃; T2℃ = 300~400℃; S3: Switch to hydrogen atmosphere, keep the product of step S2 at 400~680℃ for 1~3h, and then keep it at 700~1100℃ for 1~6h to obtain the highly uniform tungsten rhenium carbide pre-alloyed powder.

2. The method for preparing highly uniform tungsten-rhenium carbide pre-alloyed powder according to claim 1, characterized in that, In step S1, the amounts of tungsten precursor, rhenium precursor, and organic carbon source are related in the following way: The mass ratio of tungsten in the tungsten precursor to rhenium in the rhenium precursor is (70:30) to (97:3). And / or, based on the total mass of the tungsten precursor and the rhenium precursor, the mass percentage of the organic carbon source is 3-10%.

3. The method for preparing highly uniform tungsten-rhenium carbide pre-alloyed powder according to claim 1, characterized in that, In step S1, the mass ratio of tungsten in the tungsten precursor to rhenium in the rhenium precursor is (70:30) to (80:20).

4. The method for preparing highly uniform tungsten-rhenium carbide pre-alloyed powder according to claim 1, characterized in that, It satisfies at least one of the following characteristics: (1) The tungsten precursor includes at least one of ammonium metatungstate and ammonium paratungstate; (2) The rhenium precursor includes ammonium perrylate; (3) The organic carbon source includes at least one of glucose, fructose, sucrose, citric acid, lysine, histidine, and arginine.

5. The method for preparing highly uniform tungsten-rhenium carbide pre-alloyed powder according to claim 1, characterized in that, The conditions for spray drying are: oxygen content ≤2wt%, inlet air temperature 180~250℃, outlet air temperature 80~135℃, atomization pressure 0.2~0.5MPa, and fan frequency 20~50Hz.

6. The method for preparing highly uniform tungsten-rhenium carbide pre-alloyed powder according to claim 1, characterized in that, The inert gas atmosphere described in step S2 includes at least one gas selected from helium, argon, and nitrogen.

7. The method for preparing highly uniform tungsten-rhenium carbide pre-alloyed powder according to claim 1, characterized in that, In step S2, the flow rates of hydrogen and inert gas are independently 3-20 L / min; and / or, in step S3, the flow rate of hydrogen is 3-20 L / min.

8. A highly uniform tungsten-rhenium carbide pre-alloyed powder, characterized in that, The highly uniform tungsten-rhenium carbide pre-alloyed powder is prepared by the preparation method according to any one of claims 1 to 8.

9. The highly uniform tungsten-rhenium carbide pre-alloyed powder according to claim 8, characterized in that, In the highly uniform tungsten-rhenium carbide pre-alloyed powder, the mass ratio of tungsten to rhenium is (70:30) to (97:3), and the mass percentage of carbon in the highly uniform tungsten-rhenium carbide pre-alloyed powder is 0.04 to 1%.

10. The application of the highly uniform tungsten-rhenium carbide pre-alloyed powder according to any one of claims 8 to 9 in the preparation of high-temperature structural components and wear-resistant coatings.

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