CN108878234B - ZrH 2Added Y 2O 3Process for preparing-W-based secondary emitters - Google Patents

ZrH 2Added Y 2O 3Process for preparing-W-based secondary emitters Download PDF

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CN108878234B
CN108878234B CN201810615636.5A CN201810615636A CN108878234B CN 108878234 B CN108878234 B CN 108878234B CN 201810615636 A CN201810615636 A CN 201810615636A CN 108878234 B CN108878234 B CN 108878234B
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CN108878234A (en
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王金淑
华亚周
周帆
刘伟
王飞飞
赖陈
焦鹏
骆凯捷
周文元
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Beijing University of Technology
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
    • H01J9/02—Manufacture of electrodes or electrode systems
    • H01J9/04—Manufacture of electrodes or electrode systems of thermionic cathodes
    • H01J9/042—Manufacture, activation of the emissive part
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J1/00—Details of electrodes, of magnetic control means, of screens, or of the mounting or spacing thereof, common to two or more basic types of discharge tubes or lamps
    • H01J1/02—Main electrodes
    • H01J1/13—Solid thermionic cathodes
    • H01J1/14—Solid thermionic cathodes characterised by the material
    • H01J1/144—Solid thermionic cathodes characterised by the material with other metal oxides as an emissive material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J1/00—Details of electrodes, of magnetic control means, of screens, or of the mounting or spacing thereof, common to two or more basic types of discharge tubes or lamps
    • H01J1/02—Main electrodes
    • H01J1/13—Solid thermionic cathodes
    • H01J1/14—Solid thermionic cathodes characterised by the material
    • H01J1/146—Solid thermionic cathodes characterised by the material with metals or alloys as an emissive material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
    • H01J9/02—Manufacture of electrodes or electrode systems
    • H01J9/04—Manufacture of electrodes or electrode systems of thermionic cathodes
    • H01J9/042—Manufacture, activation of the emissive part
    • H01J9/045—Activation of assembled cathode
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
    • H01J9/02—Manufacture of electrodes or electrode systems
    • H01J9/04—Manufacture of electrodes or electrode systems of thermionic cathodes
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    • H01J9/047—Cathodes having impregnated bodies

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Abstract

ZrH 2Added Y 2O 3A preparation method of a-W-based secondary emitter, belonging to the technical field of preparation of cathode materials. To prepare the obtained Y 2O 3Preparing ZrH containing activator based on uniformly doped tungsten powder and 411 aluminate 2The added impregnated rare earth tungsten-based secondary cathode is tested for thermal emission performance and secondary emission performance. Found to have the activator ZrH 2The added rare earth tungsten-based secondary cathode has the most excellent thermal emission performance and secondary emission performance, and the zero field emission current density of the cathode is ZrH-free 23.1-3.4 times of rare earth tungsten-based secondary cathode is added, and the maximum secondary emission coefficient is ZrH-free 21.2 times of rare earth tungsten-based secondary cathode is added. The method is adopted to prepare the activator ZrH 2Added Y 2O 3The W-based secondary emitter has excellent thermal emission performance and secondary emission performance and is expected to be applied to a high-power magnetron.

Description

ZrH 2Added Y 2O 3Process for preparing-W-based secondary emitters
Technical Field
ZrH 2Added Y 2O 3A preparation method of a-W-based secondary emitter, belonging to the technical field of preparation of electron emission cathode materials.
Background
As the magnetron is developed toward high output power, the emission performance to the cathode, the electron ion bombardment resistance andthe service life of the device puts higher demands. Although the oxide cathode has higher emission performance, the bombardment resistance of the oxide cathode is poorer, and the oxide cathode is easy to strike fire under high working voltage, so that an oxide layer is peeled off. ThO widely applied to high-power continuous wave magnetron 2W has a large thermal emission, secondary emission performance and a long working life, but Th is radioactive and is not suitable for reuse. Although the alloy cathode has good secondary emission performance, most of the alloy cathodes are expensive in preparation cost and difficult to popularize and use on a large scale. Although the barium-tungsten cathode widely used in the magnetron at present has better thermionic and secondary electron emission performance, the barium-tungsten cathode can be subjected to violent electron ion back-bombardment action under the working environment of a high-power continuous wave magnetron, so that the surface temperature of the cathode is overhigh, BaO is quickly consumed, and the service life is shorter. The early-stage researched rare earth-molybdenum cermet cathode has excellent secondary electron emission performance, certain bombardment resistance and good emission stability, but the magnetron is difficult to start oscillation due to poor thermal emission performance of the cathode. The working principle of the high-power magnetron determines that the large-scale application of the cathode material has certain limitation. Therefore, there is still a need to research new cathode materials, which have better thermionic emission performance, higher secondary electron emission performance and bombardment resistance, so as to meet the further development of high-power and millimeter-wave magnetrons.
Disclosure of Invention
ZrH 2Added Y 2O 3-W-based secondary emitter preparation method, ZrH is mixed mechanically 2Mixing with aluminate, impregnating with yttrium oxide doped tungsten powder, pressing and sintering to obtain cathode matrix, water washing and annealing to obtain ZrH 2Added Y 2O 3-a W-based secondary emitter.
The invention provides ZrH 2Added Y 2O 3-a method for preparing a W-based secondary emitter, characterized in that the preparation process comprises the following steps:
A. selecting ammonium metatungstate [ (NH) 4) 6(H 2W 12O 40) 4H 2O](AMT) as W source, yttrium nitrate (Y (NO) 3) 3·4H 2O) is a Y source, and the Y source is respectively dissolved in deionized water, and then the two solutions are mixed and stirred uniformly; AMT and Y (NO) were added by spray dryer 3) 3Preparing the mixed solution into uniformly mixed precursor powder;
B. b, placing the precursor powder obtained in the step A into a muffle furnace for calcining, and grinding and sieving a product obtained after calcining;
C. b, placing the precursor powder obtained in the step B into a hydrogen reduction furnace for hydrogen reduction to obtain yttrium oxide doped tungsten powder;
D. c, filling the yttrium oxide doped tungsten powder obtained in the step C into a die, applying a certain bidirectional pressure through an oil press, and maintaining the pressure for a period of time to obtain a cathode blank body, wherein the cathode blank body has a certain porosity and mechanical strength;
E. d, placing the cathode blank obtained in the step D in a tungsten mesh hydrogen furnace for sintering, wherein the sintering process comprises two stages of low-temperature presintering and high-temperature sintering;
F. reacting 411 aluminate ZrH 2Mechanically mixing the mixed salt-impregnated activator by using a ball mill, uniformly mixing, and performing vacuum storage for later use;
G. embedding the cathode matrix obtained in the step E into the mixed impregnated salt activator obtained in the step F, namely 411 salt + ZrH 2Placing the molybdenum boat in a molybdenum boat, and then placing the molybdenum boat in a tungsten mesh hydrogen furnace to perform a sintering impregnation process in a hydrogen atmosphere;
H. putting the cathode obtained in the step G into water deionized water, cleaning in an ultrasonic cleaning instrument, and continuously observing the surface of the cathode in the cleaning process until no active salt exists under a microscope; soaking the cathode in alcohol for dehydration, then putting the cathode into a drying box for drying, taking the cathode out and annealing the cathode; finally obtaining the ZrH with the activator 2Added Y 2O 3-a W-based secondary emitter.
In step A of the above process, ammonium metatungstate is selected to have a purity of 99.9% and a Y content of 10 to 20wt% (preferably 15 wt%). Setting the process parameters of the spray dryer, preferably atomizationPressure 10kp aThe outlet temperature is 92-96 ℃, and the blowing rate is 0.5m 3At a feed rate of 400 ml/h/min.
In the step B of the method, the calcination temperature is 650 +/-50 ℃, and the temperature is kept for 150min +/-10 min.
In the step C of the method, the reduction process is carried out in a hydrogen atmosphere, the temperature is kept at 550 +/-50 ℃ for 120min-150min, and the temperature is kept at 1150 ℃ -1180 ℃ for 150min-180 min.
In the above method, step D, 0.12 to 0.13g of the prepared powder was weighed into a mold, and a two-way pressure of 0.75MPa was applied by an oil press while maintaining the pressure for 30 seconds.
In the step E of the method, the low-temperature sintering process is performed for 20min at 850 +/-50 ℃ and 20min at 1100 +/-100 ℃, and the high-temperature sintering process is performed for 1450-.
In step F of the method, the mechanical mixing process is to mix 411 aluminate and ZrH 2Mechanical mixing with a ball mill, preferably ZrH 2The mass percentage content is 6-19%, the preferred ball-to-material ratio is 6:1, and the ball milling time is 4 h.
In the step G of the method, the dipping process is to gradually raise the temperature to 1450-.
In the method H, the annealing process is 1050 ℃, and the temperature is kept for 30 min.
Compared with the prior art, the invention has the beneficial effects that:
1. to have ZrH 2Added Y 2O 3-W-based secondary emitter and no ZrH 2Added Y 2O 3The thermionic emission performance of the-W-based secondary emitter was tested and ZrH was found 2Added Y 2O 3the-W-based secondary emitter has the most excellent thermal electron emission performance at 1050 deg.C b，1100℃ bAnd 1150 deg.C bThe current density at zero field is 3.73A/cm respectively 2，5.27A/cm 2And 7.25A/cm 2Is free of ZrH 2Added Y 2O 3-3.1-3.4 times the thermal emission current density of the W-based secondary emitter, ZrH added to the impregnated activated aluminate 2Can greatly improve Y 2O 3-thermionic emission performance of a W-based secondary cathode.
2. To have ZrH 2Added Y 2O 3-W-based secondary emitter and no ZrH 2Added Y 2O 3The secondary electron emission performance of the-W-based secondary emitter was tested and ZrH was found 2Added Y 2O 3The W-based secondary emitter is most excellent in thermionic emission performance and has a maximum secondary emission coefficient of no ZrH 2Added Y 2O 3-1.2 times the W-based secondary emitter, ZrH being added to the impregnated activated aluminate 2Can greatly improve Y 2O 3-secondary emission performance of a W-based secondary cathode.
Drawings
The invention has 4 drawings, which are described below:
FIG. 1 SEM image and energy spectrum analysis of sintered sample
FIG. 2 SEM image of cathode surface (a) cathode without addition of activator (b) cathode with addition of activator
FIG. 3 the cathode made in example 1 was at 1200 deg.C bPost-activation pulsed voltammogram
FIG. 4 the cathode made in example 2 was at 1200 deg.C bPost-activation pulsed voltammogram
FIG. 5 cathode made in example 3 was at 1200 deg.C bPost-activation pulsed voltammogram
FIG. 6 delta-EP curves for different cathodes
Detailed Description
The present invention will be further illustrated with reference to the following examples, but the present invention is not limited to the following examples.
Example 1
(1) Selecting water-soluble ammonium metatungstate [ (NH) 4) 6(H 2W 12O 40) 4H 2O](99.9％pure), (AMT) as W source, yttrium nitrate (Y (NO) 3) 3·4H 2And O) is a Y source, and the two solutions are respectively dissolved in deionized water and then are mixed and stirred uniformly. The amount of Y contained in the sample was 15% by weight. The technological parameter of the Eyela SD-1000 type spray dryer is set as the atomization pressure of 10kp aThe outlet temperature is 92-96 ℃, and the blowing rate is 0.5m 3At a feed rate of 400ml/h, such that AMT and Y (NO) are passed through the spray dryer 3) 3The mixed solution is prepared into precursor powder which is uniformly mixed. Collecting the formed precursor powder, putting the precursor powder into a muffle furnace for calcining at the temperature of 650 ℃, preserving heat for 150min, grinding and sieving the product obtained after calcining, and collecting and preserving in vacuum to be subjected to hydrogen reduction. The hydrogen reduction test is carried out in a hydrogen reduction furnace, powder is contained in a self-made molybdenum boat, the reduction process parameters are that the temperature rising rate is 10 ℃/min, the temperature is preserved for 120 minutes at 550 ℃, then the temperature is raised to 1150 ℃, the temperature is preserved for 150 minutes, and then the furnace cooling is carried out.
(1) Weighing the prepared rare earth yttrium oxide doped tungsten powder by about 0.12-0.13g, loading the powder into a die with the diameter of a die cavity of 3mm, applying 0.75Pa bidirectional pressure by an oil press and maintaining the pressure for 30s to obtain a cathode blank with certain porosity and mechanical strength.
(2) Placing the pressed cathode blank in an L7520IIA type tungsten mesh hydrogen furnace to be sintered in hydrogen atmosphere, and keeping the temperature for 20min when the sintering process parameter is 850 ℃; and (3) preserving heat for 20min at 1100 ℃, preserving heat for 20min at 1520 ℃, and then cooling along with the furnace to obtain the cathode matrix.
(3) 411 aluminate and 18.75 weight percent of ZrH 2Mechanically mixing to obtain mixed impregnation salt, then embedding a cathode substrate obtained by sintering into the mixed impregnation salt, placing in an L7520IIA type tungsten mesh hydrogen furnace for high-temperature impregnation in a hydrogen atmosphere, wherein the set process parameters are that the temperature is slowly increased to 1520 ℃, then the temperature is rapidly increased to 1675 ℃, the temperature is kept for 1.2min, then the temperature is rapidly reduced to 1500 ℃, and then the cathode substrate is taken out after being gradually cooled to room temperature.
(4) Putting the cathode obtained after dipping into water deionized water, and cleaning in an ultrasonic cleaning instrument, wherein the cleaning process is carried outThe cathode surface was observed until the presence of the active salt was not observed under a microscope. Soaking the cathode in alcohol for dehydration, then drying in a drying oven at 80 ℃, taking out and annealing. The annealing process is 1050 ℃, the temperature is kept for 30min, and the activator ZrH is obtained by the preparation method 2Added Y 2O 3-a W-based secondary emitter.
Comparative example 2
(1) Spray drying method is adopted, and water-soluble ammonium metatungstate [ (NH) is selected 4) 6(H 2W 12O 40) 4H 2O](99.9% pure), (AMT) as W source, yttrium nitrate (Y (NO) 3) 3·4H 2And O) is a Y source, and the two solutions are respectively dissolved in deionized water and then are mixed and stirred uniformly. The amount of Y contained in the sample was 15% by weight. The technological parameter of the Eyela SD-1000 type spray dryer is set as the atomization pressure of 10kp aThe outlet temperature is 92-96 ℃, and the blowing rate is 0.5m 3At a feed rate of 400ml/h, such that AMT and Y (NO) are passed through the spray dryer 3) 3The mixed solution is prepared into precursor powder which is uniformly mixed. Collecting the formed precursor powder, putting the precursor powder into a muffle furnace for calcining at the temperature of 650 ℃, preserving heat for 150min, grinding and sieving the product obtained after calcining, and collecting and preserving in vacuum to be subjected to hydrogen reduction. The hydrogen reduction test is carried out in a hydrogen reduction furnace, powder is contained in a self-made molybdenum boat, the reduction process parameters are that the temperature rising rate is 10 ℃/min, the temperature is preserved for 120 minutes at 550 ℃, then the temperature is raised to 1150 ℃, the temperature is preserved for 150 minutes, and then the furnace cooling is carried out.
(2) Weighing the prepared rare earth yttrium oxide doped tungsten powder about 0.12-0.13g, loading the powder into a die with the diameter of a die cavity of 3mm, applying 0.75MPa bidirectional pressure by an oil press and maintaining the pressure for 30s to obtain a cathode blank with certain porosity and mechanical strength.
(3) Placing the pressed cathode blank in an L7520IIA type tungsten mesh hydrogen furnace to be sintered in hydrogen atmosphere, and keeping the temperature for 20 minutes when the sintering process parameter is 850 ℃; and (3) preserving the heat for 20min at 1100 ℃, preserving the heat for 20min at 1520 ℃, and then cooling along with the furnace to obtain the cathode matrix.
(4) Burying the sintered cathode substrate in 411 aluminate, placing in an L7520IIA tungsten mesh hydrogen furnace, and performing high-temperature impregnation in hydrogen atmosphere, wherein the set process parameters comprise slowly heating to 1520 ℃, then quickly heating to 1675 ℃, keeping the temperature for 1.2min, then quickly cooling to 1500 ℃, and then gradually taking out after the temperature is reduced to room temperature.
(5) And (3) putting the cathode obtained after dipping into water deionized water, cleaning in an ultrasonic cleaning instrument, and continuously observing the surface of the cathode in the cleaning process until no active salt exists under a microscope. Soaking the cathode in alcohol for dehydration, then drying in a drying oven at 80 ℃, taking out and annealing. The annealing process is 1050 ℃, the temperature is kept for 30min, and the activator-free ZrH is obtained by the preparation method 2Added Y 2O 3-a W-based secondary emitter.
Comparative example 3
(1) Selecting water-soluble ammonium metatungstate [ (NH) 4) 6(H 2W 12O 40) 4H 2O](99.9% pure), (AMT) as W source, yttrium nitrate (Y (NO) 3) 3·4H 2And O) is a Y source, and the two solutions are respectively dissolved in deionized water and then are mixed and stirred uniformly. The amount of Y contained in the sample was 15% by weight. The technological parameter of the Eyela SD-1000 type spray dryer is set as the atomization pressure of 10kp aThe outlet temperature is 92-96 ℃, and the blowing rate is 0.5m 3At a feed rate of 400ml/h, such that AMT and Y (NO) are passed through the spray dryer 3) 3The mixed solution is prepared into precursor powder which is uniformly mixed. Collecting the formed precursor powder, putting the precursor powder into a muffle furnace for calcining at the temperature of 650 ℃, preserving heat for 150min, grinding and sieving the product obtained after calcining, and collecting and preserving in vacuum to be subjected to hydrogen reduction. The hydrogen reduction test is carried out in a hydrogen reduction furnace, powder is contained in a self-made molybdenum boat, the reduction process parameters are that the temperature rising rate is 10 ℃/min, the temperature is preserved for 120 minutes at 550 ℃, then the temperature is raised to 1150 ℃, the temperature is preserved for 150 minutes, and then the furnace cooling is carried out.
(2) Weighing the prepared rare earth yttrium oxide doped tungsten powder by about 0.12-0.13g, loading the powder into a die with the diameter of a die cavity of 3mm, applying 0.75Pa bidirectional pressure by an oil press and maintaining the pressure for 30s to obtain a cathode blank with certain porosity and mechanical strength.
(3) Placing the pressed cathode blank in an L7520IIA type tungsten mesh hydrogen furnace to be sintered in hydrogen atmosphere, and keeping the temperature for 20min when the sintering process parameter is 850 ℃; and (3) preserving heat for 20min at 1100 ℃, preserving heat for 20min at 1520 ℃, and then cooling along with the furnace to obtain the cathode matrix.
(4) 411 aluminate and 6.25 weight percent of ZrH 2Mechanically mixing to obtain mixed impregnation salt, then embedding a cathode substrate obtained by sintering into the mixed impregnation salt, placing in an L7520IIA type tungsten mesh hydrogen furnace for high-temperature impregnation in a hydrogen atmosphere, wherein the set process parameters are that the temperature is slowly increased to 1520 ℃, then the temperature is rapidly increased to 1675 ℃, the temperature is kept for 1.2min, then the temperature is rapidly reduced to 1500 ℃, and then the cathode substrate is taken out after being gradually cooled to room temperature.
(5) And (3) putting the cathode obtained after dipping into water deionized water, cleaning in an ultrasonic cleaning instrument, and continuously observing the surface of the cathode in the cleaning process until no active salt exists under a microscope. Soaking the cathode in alcohol for dehydration, then drying in a drying oven at 80 ℃, taking out and annealing. The annealing process is 1050 ℃, the temperature is kept for 30min, and the activator ZrH is obtained by the preparation method 2Added Y 2O 3-a W-based secondary emitter.
The invention is not limited to the above embodiments, but includes any modifications, equivalents, improvements, etc. without departing from the spirit and scope of the invention.

Claims (13)

1. ZrH 2Added Y 2O 3-a method for preparing a W-based secondary emitter, characterized in that the preparation process comprises the following steps:
A. selecting ammonium metatungstate [ (NH) 4) 6(H 2W 12O 40) 4H 2O](AMT) as W source, yttrium nitrate（Y(NO 3) 3∙4H 2O) is a Y source, and the Y source is respectively dissolved in deionized water, and then the two solutions are mixed and stirred uniformly; AMT and Y (NO) were added by spray dryer 3) 3Preparing the mixed solution into uniformly mixed precursor powder;
B. b, placing the precursor powder obtained in the step A into a muffle furnace for calcining, and grinding and sieving a product obtained after calcining;
C. b, placing the precursor powder obtained in the step B into a hydrogen reduction furnace for hydrogen reduction to obtain yttrium oxide doped tungsten powder;
D. c, filling the yttrium oxide doped tungsten powder obtained in the step C into a die, applying a certain bidirectional pressure through an oil press, and maintaining the pressure for a period of time to obtain a cathode blank body, wherein the cathode blank body has a certain porosity and mechanical strength;
E. d, placing the cathode blank obtained in the step D in a tungsten mesh hydrogen furnace for sintering, wherein the sintering process comprises two stages of low-temperature presintering and high-temperature sintering;
F. mixing 411 aluminate and ZrH 2Mechanically mixing the mixed salt-impregnated activator by using a ball mill, uniformly mixing, and performing vacuum storage for later use;
G. embedding the cathode matrix obtained in the step E into the mixed impregnated salt activator obtained in the step F, namely 411 salt + ZrH 2Placing the molybdenum boat in a molybdenum boat, and then placing the molybdenum boat in a tungsten mesh hydrogen furnace to perform a sintering impregnation process in a hydrogen atmosphere;
H. putting the cathode obtained in the step G into water deionized water, cleaning in an ultrasonic cleaning instrument, and continuously observing the surface of the cathode in the cleaning process until no active salt exists under a microscope; soaking the cathode in alcohol for dehydration, then putting the cathode into a drying box for drying, taking the cathode out and annealing the cathode; finally obtaining the ZrH with the activator 2Added Y 2O 3-a W-based secondary emitter.
2. A ZrH as claimed in claim 1 2Added Y 2O 3-a process for the preparation of a W-based secondary emitter, characterized in that, in step A,the purity of the selected ammonium metatungstate is 99.9 percent, and the content of Y is 10 to 20 weight percent.
3. A ZrH as claimed in claim 2 2Added Y 2O 3-W-based secondary emitter, characterized in that Y is contained in an amount of 15% by weight.
4. A ZrH as claimed in claim 1 2Added Y 2O 3The preparation method of the-W-based secondary emitter is characterized in that in the step B of the method, the calcination temperature is 650 +/-50 ℃, and the temperature is kept for 150min +/-10 min.
5. A ZrH as claimed in claim 1 2Added Y 2O 3The preparation method of the-W-based secondary emitter is characterized in that in the step C of the method, the reduction process is carried out in a hydrogen atmosphere, the temperature is kept at 550 +/-50 ℃ for 120min-150min, and the temperature is kept at 1150 ℃ -1180 ℃ for 150min-180 min.
6. A ZrH as claimed in claim 1 2Added Y 2O 3A method for preparing a W-based secondary emitter, characterized in that, in the above method step D, 0.12 to 0.13g of the prepared powder is weighed into a mold, and a two-way pressure of 0.75Mpa is applied by an oil press while maintaining the pressure for 30 seconds.
7. A ZrH as claimed in claim 1 2Added Y 2O 3The preparation method of the-W-based secondary emitter is characterized in that in the step E of the method, the low-temperature sintering process is performed for 20min at 850 +/-50 ℃ and 20min at 1100 +/-100 ℃ in the sintering process, and the high-temperature sintering process is performed for 1450 +/-1550 ℃ and 20 min.
8. A ZrH according to claim 7 2Added Y 2O 3-W-based secondary emitter preparation method, characterized in that the temperature of the high temperature sintering process is 1520 ℃.
9. A ZrH as claimed in claim 1 2Added Y 2O 3-a process for the preparation of a W-based secondary emitter, characterized in that in step F of the above process, the mechanical mixing is carried out by reacting 411 aluminate with ZrH 2Mechanical mixing with ball mills, ZrH 2The mass percentage content is 6-19%, the ball-material ratio is 6:1, and the ball milling time is 4 h.
10. A ZrH as claimed in claim 1 2Added Y 2O 3The preparation method of the-W-based secondary emitter is characterized in that in the step G of the method, the dipping process comprises the steps of gradually raising the temperature to 1450-1550 ℃, then raising the temperature to 1675 ℃ within 1-2min, keeping the temperature for 1.2min, then reducing the temperature to 1500 ℃ within 1 min, and then gradually taking out the emitter after the temperature reaches the room temperature.
11. A ZrH as claimed in claim 10 2Added Y 2O 3The preparation method of the-W-based secondary emitter is characterized in that the dipping process comprises the steps of gradually heating to 1520 ℃, then heating to 1675 ℃ within 1-2min, keeping the temperature for 1.2min, then cooling to 1500 ℃ within 1 min, and then gradually taking out the W-based secondary emitter after the temperature is gradually cooled to room temperature.
12. A ZrH as claimed in claim 1 2Added Y 2O 3The preparation method of the-W-based secondary emitter is characterized in that in the method H, the annealing process is 1050 ℃, and the temperature is kept for 30 min.
13. ZrH obtainable by a process according to any of claims 1 to 12 2Added Y 2O 3-a W-based secondary emitter.
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