WO2016061721A1 - Method for preparing rare-earth oxide dispersion strengthened fine-grained tungsten material - Google Patents

Abstract

A method for preparing a rare-earth oxide dispersion strengthened fine-grained tungsten material, comprising: according to a condition that a mass percentage of rare-earth oxide is 0.1-2%, and the remaining composition is W, weighing soluble rare-earth salt and tungstic acid salt, and respectively preparing 50-100 g/L of rare-earth saline solution and 150-300 g/L of tungstic acid saline solution; adding a minor amount of alkali into the rare-earth salt to control the pH to be 7-8, adding an organic dispersing agent, and stirring to enable the rare-earth salt to form uniformly suspending R(OH)₃ colloidal particles (R represents a rare-earth element); adding the tungstic acid saline solution into the R(OH)₃ colloidal particles, adding a minor amount of acid to control the pH to be 6-7, adding the organic dispersing agent, stirring to enable the tungstic acid salt to form tungstic acid micro-particles, precipitating and coating the R(OH)₃ colloidal particles with the R(OH)₃ colloidal particles as a core, and forming coprecipitated coated colloidal particles; conducting spray drying on the coprecipitated coated colloidal particles to obtain a composite precursor powder of tungsten and rare-earth oxide; calcining, conducting thermal reduction via hydrogen, and preparing superfine nanometer tungsten powder having a particle size of 50-500 nm; and conducting normal high-temperature sintering after a general pressing forming. The high-performance fine-grained tungsten material dispersed and strengthened by a minor amount of rare-earth oxide prepared by the above method has a density approximate to full density (≥98.5%), and uniform and small tungsten grains having an average size of 5-10 μm; in addition, rare-earth oxide particles having a particle size of 100 nm - 500 nm are uniformly distributed in a tungsten crystal or a crystal boundary.

Description

 Method for preparing rare earth oxide dispersion strengthened fine grain tungsten material  Technical field

The invention relates to the field of nano materials and powder metallurgy, in particular to a preparation method of rare earth oxide dispersion strengthened fine grain tungsten material prepared by nano composite technology.

technical background

Tungsten has high melting point, high hardness, good high temperature strength, thermal conductivity, electrical conductivity, low coefficient of thermal expansion, low sputtering with plasma, no chemical reaction with H, low H ⁺ retention, etc. High-temperature structural materials and functional materials are widely used as materials for plasma materials and divertor components in the field of nuclear fusion.

Among the tungsten materials that have been applied, pure tungsten materials are typical high temperature materials that are widely used at present. At present, high-purity powder and material grain boundary purification methods are used at home and abroad to prepare sintered pure tungsten materials, and then tungsten materials are strengthened by large deformation processing methods. The grain size is about 100 μm, and the ductile-brittle transition temperature (DBTT) is 300-350 °C. The crystallization temperature is 1300~1350 °C, the tensile strength at room temperature is above 500MPa, and the tensile strength at 1000 °C is 400MPa. However, due to the limitations of conventional powder sintering and rolling methods, pure tungsten materials have defects such as very coarse structure, fibrous orientation, high DBTT, low recrystallization temperature, and high brittleness. The addition of second phase particles to refine tungsten grains and to diffusely strengthen pure tungsten has become an important direction of current development. Based on this, domestic Zhou Zhangjian et al. in 2010, in the patent 'Method for preparing nano-oxide dispersion-reinforced ultra-fine-grained tungsten-based composite materials' (patent number: ZL201010250552.X), with tungsten powder, Y ₂ O ₃ or Y The sintering aid Ti is used as a raw material, and the tungsten powder is solid-dissolved with Y ₂ O ₃ or Y and Ti to form an ultrafine alloyed powder by mechanical alloying, and then the rare earth yttrium oxide dispersion strengthening is prepared by discharge plasma sintering. The tungsten material has a relative density of 96% to 99% and a tungsten grain size of ≤3 μm, and has good mechanical properties and thermal shock resistance. In addition, foreign Kim et al. in 2009 ' Fabrication of high temperature oxides dispersion strengthened tungsten composites by spark plasma sintering process', Mu ñoz et al. in 2011 article 'La ₂ O ₃ -reinforced W and WV alloys produced by hot isostatic Pressing' is also used to prepare tungsten and rare earth oxide composite powder by mechanical alloying, and the oxide dispersion strengthened tungsten material is prepared by spark plasma sintering (SPS) and hot pressing method. The results show that the addition of trace rare earth oxide can refine the tungsten crystal. Granules, increased strength and resistance to high heat load. Guo Zhimeng et al. in the patent 'Preparation method of a nano-cerium oxide dispersion-strengthened tungsten alloy' (Application No.: 201310123415.3), the preparation method described above is improved: the cerium nitrate is dissolved in alcohol, and then with ammonium paratungstate ( APT) is subjected to mixed ball milling, and after hydrogen reduction after drying, then 0.1% to 1% of Ni is added as a sintering activator, and finally a tungsten material having a density of 18.28 to 19.2 g/cm ³ is prepared by high temperature sintering. The above studies have fully demonstrated the advantages of adding rare earth oxides in tungsten to refine tungsten grains, improve the mechanical properties and thermal shock resistance of tungsten. However, the above preparation method has some problems: the preparation of the powder by high-energy ball milling or mechanical alloying tends to produce uneven distribution of components and introduction of heterogeneous impurities, and the sintering method of SPS and hot pressing is not suitable for large-scale preparation of engineering. While Guo Zhimeng et al.'s method improves the uniformity of dispersion distribution of oxides in tungsten matrix, Ni element must be added as a sintering activator, while Ni element is strictly prohibited in many fields, such as nuclear fusion and nuclear fission. This will impose huge limitations on the scope of its application. The inventor of the present patent has applied for and obtained a national invention patent 'Preparation method of ultrafine activated tungsten powder (patent number: ZL201010049432.3)', in which sol-spray drying-heat is applied The ultrafine or nano-activated tungsten powder is prepared by a reduction technique, and any one or more of Ni, Co, and Fe trace activation elements are added to the powder. The powder composition of the invention is uniformly distributed and does not introduce an impurity element as compared with high energy ball milling or mechanical alloying. However, due to the poor compatibility of tungsten and rare earth oxide particles on the surface, the sol-spray drying method is used to directly prepare tungsten materials containing trace rare earth oxides. The dispersion strengthening effect of rare earth oxide particles on tungsten is very limited, resulting in poor performance of materials. It is difficult to meet the requirements for the use of nuclear fusion tungsten materials.

 Summary of the invention

 In view of the above problems in the preparation of high performance rare earth oxide dispersion strengthened fine grain tungsten material, the present invention employs heterogeneous precipitation - spray drying - Calcination - Thermal reduction - Preparation by conventional sintering technology High performance rare earth oxide dispersion strengthened fine grain tungsten material. The rare earth oxide dispersion-enhanced fine-grained tungsten material prepared by the method of the invention has a density close to full density ( ≥98.5%), the rare earth oxide particles are uniformly distributed in the tungsten grains and the tungsten grain boundaries, the structure is uniform and fine, and the average grain size is 10 μm. Below, it has good room temperature, high temperature mechanical properties and high heat load impact resistance.

The present invention provides a rare earth oxide super-uniform dispersion-distributed fine-grained tungsten material, characterized in that the fine-grained tungsten material contains one or more of Y ₂ O ₃ , La ₂ O ₃ and CeO ₂ And the mass percentage of the rare earth oxide ranges from 0.1 to 2%, and the remaining component is W.

 The above-mentioned ultra-uniform dispersion distribution of rare earth oxide enhances the fine-grained tungsten material, and the preparation process thereof is as follows:

(1) The mass percentage of the rare earth oxide is 0.1 to 2%, and the remaining component is W. The soluble rare earth salt and the tungstate are weighed and prepared into a rare earth salt solution of 50 to 100 g/L and a tungstate solution of 150 to 300 g/L, respectively. First, adding a base to the rare earth salt to control the pH between 7 and 8, and adding an organic dispersant, stirring to form a uniform suspension of the R(OH) ₃ particle colloid (R represents a rare earth element); then adding the tungstate solution to the R In the (OH) ₃ colloid, add acid to control the pH at 6~7, add organic dispersant, stir to form tungstic acid microparticles, and use R(OH) ₃ colloidal particles as the core, and precipitate the coating on R ( OH) ₃ around the colloidal particles, eventually forming a coprecipitated coated particle colloid. The colloid is spray-dried at 350~450 °C to obtain a composite precursor powder of tungsten and rare earth oxide; the composite precursor powder is calcined at 300~600 °C, and the calcination time is 1~4h, and the solution is agglomerated and sieved. After that, the hydrogen is reduced at 600~850 °C for 2~6h to prepare ultrafine/nano tungsten powder containing trace rare earth oxides with a particle size of 50~500nm; the rare earth oxide is Y ₂ O ₃ One or more of La ₂ O ₃ or CeO ₂ ;

 (2) The ultrafine/nano tungsten powder containing trace rare earth oxide in step (1) is 150~300MPa Forming or cold isostatic pressing;

 (3) The press-formed compact is subjected to conventional high-temperature sintering in a high-temperature sintering furnace at a sintering temperature of 1800 to 2000 °C. The holding time is 1 ~ 5h, and the dense high-performance rare earth oxide super-diffused distribution enhanced fine-grained tungsten material is obtained.

 The tungstate is ammonium metatungstate, ammonium paratungstate or ammonium tungstate.

 The rare earth salt is a nitrate, oxalate, carbonate, chloride or sulfate of Y, La or Ce.

 The stirring speed is 1000~5000 rpm.

 The spray drying head rotates at a speed of 20,000 to 30,000 rpm.

 The reaction dispersant is stearic acid, polyethylene glycol, urea, N, N-dimethylformamide, OP emulsifier, Tween-20 Or sodium dodecyl sulfate, the mass of the reaction dispersant is 0.1~1.5% of the mass of the rare earth salt solution or the tungstate solution.

The pH is controlled, the added acid is HCl, HNO ₃ or oxalic acid; the added base is NaOH, KOH or ammonia.

 The oxide dispersion-strengthened tungsten material prepared by the invention relative to the prior art has the following advantages:

 1. 'Non-homogeneous precipitation - spray drying' compared to conventional high energy ball milling mechanical alloying The rare earth oxide is added to the tungsten matrix, the heterogeneous precipitation improves the compatibility of the surface of the tungsten and the rare earth oxide particles, and the spray drying is used to achieve the uniformity of the composition and structure of the powder and the alloy, so that the rare earth elements are more distributed in the tungsten matrix. Uniform and no introduction of foreign matter;

 2. Compared with high energy ball milling mechanical alloying, 'heterogeneous precipitation - spray drying - calcination - The ultrafine tungsten composite powder containing trace rare earth oxide prepared by hydrogen reduction method has greater sintering activity; the powder prepared by the invention can reach 98.5% by conventional sintering at 1800-2000 °C. The above density, sintered body grain size is 5 ~ 10μm, and the structure is more uniform, with excellent room temperature, high temperature and toughness.

3. The invention adopts the conventional sintering method to prepare the rare earth oxide dispersion-strengthened fine-grained tungsten material, and the process is simple and suitable for engineering preparation.

Detailed ways

 The invention will be further illustrated by the following examples, without limiting the invention.

 Example 1

For example, a dispersion-strengthened fine-grained tungsten material having a composition of W-0.1 wt% Y ₂ O ₃ is prepared.

 (1) First, according to the mass fraction of the rare earth oxide to be prepared, the soluble rare earth salt and the tungstate are weighed according to the mass ratio, that is, weighed 1.02 g of cerium nitrate, 411.27 g of ammonium metatungstate, respectively, was prepared into a 50 g/L rare earth salt solution and a 150 g/L tungsten salt solution.

(2) First, slowly add 10% by weight of ammonia water to the cerium nitrate solution, adjust the pH to 7.2, and add 0.2g PEG400 as the reaction dispersant. Under the action of ultrasonic vibration and electric mixer stirring, make the rare earth salt and The alkali reacts to form a uniform suspension of Y(OH) ₃ particles colloid; then the tungsten salt solution is added to the Y(OH) ₃ colloid, the oxalic acid at a concentration of 10 wt% is slowly added dropwise, the pH is adjusted to 6.5, and 2 g of PEG400 is added as a reaction. Dispersing agent, under the action of ultrasonic vibration and electric mixer stirring, the tungstate forms tungsten acid microparticles, and Y(OH) ₃ colloidal particles are used as the core, and the precipitate is coated around the Y(OH) ₃ colloidal particles to form a total Precipitating coated particle colloid;

 (3) Then, the colloid was spray-dried at 360 °C, and the spray head rotation speed was 20000 rpm / A composite precursor powder of tungsten and rare earth cerium oxide is obtained.

(4) The composite precursor powder was calcined at 350 °C for 2 h; after deagglomeration and sieving, it was kept at 78 ° C for ₂ h under H ₂ atmosphere; and an ultra-containing Y ₂ O _{3 was obtained} . Fine tungsten powder.

(5) Molding of ultrafine W composite powder containing 0.1wt% Y ₂ O ₃ , calcining the compact and sintering at 1950 °C for 2 h to obtain W-0.1wt% Y ₂ O ₃ material, the density of the material Above 99.2%, the microstructure is fine and uniform, and the grain size is below 10 μm; the material does not crack on the surface of the sample under the impact of high heat flux density of 200 MW/m ² .

 Example 2:

For example, a dispersion-strengthened fine-grained tungsten material having a composition of W-0.3 wt% La ₂ O ₃ is prepared.

 (1) First, according to the mass fraction of the rare earth oxide to be prepared, the soluble rare earth salt and the tungstate are weighed according to the mass ratio, that is, weighed 1.53 g of bismuth oxalate, 410.45 g of ammonium paratungstate, respectively, were prepared into a 60 g/L rare earth salt solution and a 200 g/L tungsten salt solution.

(2) First, slowly add NaOH at a concentration of 10 wt% to the bismuth oxalate solution, adjust the pH to 7.3, and add 0.3 g of N,N-dimethylformamide as a reaction dispersant, stir in ultrasonic vibration and electric mixer. The rare earth salt reacts with the base to form a uniform suspension of La(OH) ₃ colloid; then the tungsten salt solution is added to the La(OH) ₃ colloid, and the concentration of 10 wt% HCl is slowly added dropwise to adjust the pH to 6.8, and adding 1.5g PEG400 as a reaction dispersant, the tungstate is formed into tungstic acid microparticles under the action of ultrasonic vibration and electric mixer stirring, and La(OH) ₃ colloidal particles are used as the core, and the precipitate is coated on La(OH). ₃ ) around the colloidal particles, eventually forming a coprecipitated coated particle colloid;

 (3) Then, the colloid was spray-dried at 400 °C, and the spray head rotation speed was 20000 rpm / A composite precursor powder of tungsten and rare earth cerium oxide is obtained.

(4) The composite precursor powder was calcined at 350 °C for 2 h; after deagglomeration and sieving, it was kept at 78 ° C for ₂ h under H ₂ atmosphere; and an ultra-containing 0.3 wt% La ₂ O _{3 was obtained} . Fine tungsten powder.

(5) Molding an ultrafine W composite powder containing a trace amount of rare earth La ₂ O ₃ , calcining the compact and sintering at 1950 ° C for 3 h to obtain a W-0.3 wt% La ₂ O ₃ material, the density of which is More than 99.1%, the microstructure is fine and uniform, and the grain size is below 8μm. The material does not crack on the surface of the sample under the impact of high heat flux density of 200MW/m ² .

 Example 3:

For example, a dispersion-strengthened fine-grained tungsten material having a composition of W-0.5 wt% CeO ₂ is prepared.

 (1) First, according to the mass fraction of the rare earth oxide to be finally prepared, the soluble rare earth salt and the tungstate are weighed according to the mass ratio, that is, 2.10 g Barium carbonate, 409.6 g of ammonium tungstate, was prepared into a 70 g/L rare earth salt solution and a 220 g/L tungsten salt solution, respectively.

(2) First, slowly add KOH at a concentration of 10 wt% to the cesium carbonate solution, adjust the pH to 7.5, and add 0.3 g of stearic acid as a reaction dispersant. Under the action of ultrasonic vibration and electric mixer stirring, the rare earth is made. The salt reacts with the base to form a uniform suspension of Ce(OH) ₃ colloid; then the tungsten salt solution is added to the Ce(OH) ₃ colloid, and the concentration of 10 wt% of HNO _{3 is} slowly added dropwise, the pH is adjusted to 6.5, and 2.5 is added. g Stearic acid as a reaction dispersant, the tungstate is formed into tungstic acid microparticles under the action of ultrasonic vibration and electric mixer stirring, and Ce(OH) ₃ colloidal particles are used as the core, and the precipitate is coated with Ce(OH) ₃ colloid. Around the particles, a coprecipitated coated particle colloid is finally formed;

 (3) Then, the colloid was spray-dried at 400 °C, and the rotation speed of the spray head was 25,000 rpm. A composite precursor powder of tungsten and rare earth cerium oxide is obtained.

(4) The composite precursor powder is calcined at 400 °C for 2 hours; after deagglomeration and sieving, it is reduced in two steps under H ₂ atmosphere, the first step is kept at 60 ° C for 2 h, the second step is The steel was kept at 800 ° C for 2 h to obtain an ultrafine tungsten powder containing 0.5 wt% of CeO ₂ .

(5) The ultrafine W composite powder containing trace rare earth CeO ₂ is cold isostatically pressed, and the compact is calcined and then sintered at 1950 ° C for 4 h to obtain W-0.5 wt% CeO ₂ material. The density of the material is 99.3. Above, the microstructure is fine and uniform, and the grain size is below 8 μm; the material does not crack on the surface of the sample under the impact of high heat flux density of 200 MW/m ² .

 Example 4:

For example, a dispersion-strengthened fine-grained tungsten material having a composition of W-0.3 wt% Y ₂ O ₃ -0.3 wt% La ₂ O ₃ is prepared.

 (1) Firstly, according to the mass fraction of the rare earth oxide to be prepared, the soluble rare earth salt and the tungstate are weighed according to the mass ratio, that is, respectively weighed 1.52g bismuth nitrate, 2.18g lanthanum chloride, 409.2g ammonium metatungstate, lanthanum nitrate and lanthanum chloride are mixed to form 80g/L rare earth salt solution, 250g/L Tungsten salt solution.

(2) First, slowly add 10% by weight of ammonia water to the mixed solution of cerium nitrate and cerium chloride, adjust the pH to 7.8, and add 0.4g of sodium dodecyl sulfonate as the reaction dispersant in ultrasonic vibration and Under the action of electric mixer, the rare earth salt reacts with the base to form a uniform suspension of Y(OH) ₃ + La(OH) ₃ particles colloid; then the tungsten salt solution is added to the Y(OH) ₃ + La(OH) ₃ colloid. Slowly add oxalic acid at a concentration of 10 wt%, adjust the pH to 6.2, and add 3.0 g of sodium dodecyl sulfate as a reaction dispersant to form tungstate into tungstic acid under the action of ultrasonic vibration and electric mixer stirring. Microparticles, with Y(OH) ₃ + La(OH) ₃ colloidal particles as the core, precipitated around the Y(OH) ₃ + La(OH) ₃ colloidal particles, and finally formed a coprecipitated coated particle colloid;

 (3) Then, the colloid was spray-dried at 450 °C, and the rotation speed of the spray head was 25,000 rpm. A composite precursor powder of tungsten and rare earth cerium oxide + cerium oxide was obtained.

(4) The composite precursor powder was calcined at 400 °C for 3 h; after deagglomeration and sieving, it was kept at 80 ° C for ₂ h under H ₂ atmosphere; and 0.3 wt% La ₂ O ₃ -0.3 was obtained. Ultrafine tungsten powder of wt% La ₂ O ₃ .

(5) After molding the ultrafine WY ₂ O ₃ -La ₂ O ₃ composite tungsten powder, the compact is pre-fired at 1000 °C for 2 h and then sintered at 1920 °C for 3 h to obtain W-0.3 wt% Y ₂ O ₃ - 0.3wt% La ₂ O ₃ material, the density of the material is above 99.4%, the microstructure is fine and uniform, and the grain size is below 6μm; the material does not crack on the surface of the sample under the impact of high heat flux density of 300MW/m ² .

 Example 5:

For example, a dispersion-strengthened fine-grained tungsten material having a composition of W-0.3 wt% Y ₂ O ₃ - 0.3 wt% La ₂ O ₃ - 0.3 wt% CeO ₂ is prepared.

 (1) Firstly, according to the mass fraction of the rare earth oxide to be prepared, the soluble rare earth salt and the tungstate are weighed according to the mass ratio, that is, respectively weighed 1.85g barium sulfate, 0.8g barium nitrate, 1.52g barium nitrate, 409g ammonium metatungstate, mixed with barium sulfate, barium nitrate and barium nitrate to prepare a 100g/L rare earth salt solution. 300 g / L of tungsten salt solution.

(2) Firstly, slowly add NaOH with a concentration of 10 wt% in a mixed solution of barium sulfate, barium nitrate and barium nitrate, adjust the pH to 8.0, and add 0.5 g of Tween-20 as a reaction dispersant in ultrasonic vibration and electric Under the action of agitator, the rare earth salt is reacted with a base to form a uniform suspension of Y(OH) ₃ + La(OH) ₃ + Ce(OH) ₃ particles colloid; then the tungsten salt solution is added to Y(OH) ₃ + La ( In the OH) ₃ + Ce(OH) ₃ colloid, slowly add HCl at a concentration of 10 wt%, adjust the pH to 6.0, and add 4.0 g Tween-20 as a reaction dispersant in the ultrasonic vibration and stirring of the electric mixer. The tungstate is formed into a tungstic acid microparticle, and the Y(OH) ₃ + La(OH) ₃ + Ce(OH) ₃ colloidal particle is used as a core, and the precipitate is coated on Y(OH) ₃ + La(OH) ₃ + Around the colloidal particles of Ce(OH) ₃ , a coprecipitated coated particle colloid is finally formed;

 (3) Then, the colloid is spray-dried at 450 °C, and the rotation speed of the spray head is 30,000 rpm / A composite precursor powder of tungsten and rare earth cerium oxide + cerium oxide + cerium oxide was obtained.

(4) The composite precursor powder is calcined at 500 °C for 3 hours; after deagglomeration and sieving, in the H ₂ atmosphere, the first step is kept at 60 ° C for 2 h, and the second step is kept at 800 ° C. 4h, an ultrafine tungsten powder containing 0.3% by weight of La ₂ O ₃ -0.3% by weight of La ₂ O ₃ -0.3% by weight of CeO ₂ was obtained. (5) Molding an ultrafine W composite powder containing a trace amount of rare earth Y ₂ O ₃ , La ₂ O ₃ , CeO ₂ , calcining the compact, and sintering at 1950 ° C for 4 h to obtain W-0.3 wt% Y ₂ O ₃ - 0.3wt% La ₂ O ₃ -0.3wt% CeO ₂ material, the density of the material is above 99.1%, the microstructure is fine and uniform, the grain size is below 5μm; the material is impacted at 300MW/m ² high heat flux density No cracking occurred on the surface of the lower sample.

Claims (7)

1. A method for preparing a rare earth oxide dispersion strengthened fine grain tungsten material, comprising the steps of:

   (1) According to the mass percentage of rare earth oxides is 0.1 to 2%, and the remaining components are W, and the soluble rare earth salts and tungstates are weighed and formulated into 50-100 g/L rare earth salt solution and 150-300 g/L, respectively. Tungstate solution; firstly add alkali in the rare earth salt to control the pH between 7 and 8, and add an organic dispersant, stir to form a uniform suspension of R(OH) ₃ particles colloid, R is a rare earth element; then tungstate The solution is added to the R(OH) ₃ colloid, acid is added to control the pH at 6~7, and the organic dispersant is added, and the tungstate is stirred to form the tungstic acid microparticles, and the R(OH) ₃ colloidal particles are used as the core, and the precipitate is packaged. Covering the R(OH) ₃ colloidal particles, the coprecipitated coated particle colloid is finally formed; the colloid is spray-dried at 350~450 °C to obtain a composite precursor powder of tungsten and rare earth oxide; the composite precursor powder is Calcination at 300~600 °C, calcination time is 1~4h, after deagglomeration, sieving, hydrogen reduction at 600~850 °C, reduction time is 2~6h, preparation of trace rare earth oxide, particle size at 50~ 500nm ultrafine/nano tungsten powder; the rare earth oxide is Y ₂ O ₃ , one or more of La ₂ O ₃ or CeO ₂ ;

   (2) The ultrafine/nano tungsten powder containing trace rare earth oxide in (1) is 150~300MPa Forming or cold isostatic pressing;

   (3) The compacted compact is subjected to conventional high-temperature sintering in a high-temperature sintering furnace at a sintering temperature of 1800 to 2000 ° C and a holding time of 1 ～ At 5h, a dense high-performance rare earth oxide super-diffused dispersion-enhanced fine-grained tungsten material is obtained.
2. According to claim 1 The method for preparing a rare earth oxide dispersion-strengthened fine-grained tungsten material, characterized in that the tungstate is ammonium metatungstate, ammonium paratungstate or ammonium tungstate.
3. The method for preparing a rare earth oxide dispersion-strengthened fine-grained tungsten material according to claim 1, wherein the rare earth salt is Y, La, Ce Nitrate, oxalate, carbonate, chloride or sulfate.
4. The method for preparing a rare earth oxide dispersion-strengthened fine-grained tungsten material according to claim 1, wherein the stirring speed is 1000 to 5000 rpm / Minute.
5. The method for preparing a rare earth oxide dispersion-strengthened fine-grained tungsten material according to claim 1, wherein the spray drying nozzle has a rotational speed of 20,000 to 30,000 Transfer / minute.
6. The method for preparing a rare earth oxide dispersion-strengthened fine-grained tungsten material according to claim 1, wherein the reaction dispersant is stearic acid, polyethylene glycol, urea, N, N-dimethylformamide, OP emulsifier, Tween-20 or sodium dodecyl sulfate, the mass of the reaction dispersant is 0.1~1.5% of the mass of the rare earth salt solution or the tungstate solution. .
7. The method for preparing a rare earth oxide dispersion-strengthened fine-grained tungsten material according to claim 1, wherein the acid added in step (1) controls the pH value, and the added acid is HCl, HNO ₃ or oxalic acid; A base is added to the salt to control the pH, and the base added is NaOH, KOH or ammonia.