CN110676137A - Preparation method of cathode for magnetron - Google Patents
Preparation method of cathode for magnetron Download PDFInfo
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- CN110676137A CN110676137A CN201910870422.7A CN201910870422A CN110676137A CN 110676137 A CN110676137 A CN 110676137A CN 201910870422 A CN201910870422 A CN 201910870422A CN 110676137 A CN110676137 A CN 110676137A
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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
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J23/00—Details of transit-time tubes of the types covered by group H01J25/00
- H01J23/02—Electrodes; Magnetic control means; Screens
- H01J23/04—Cathodes
- H01J23/05—Cathodes having a cylindrical emissive surface, e.g. cathodes for magnetrons
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J25/00—Transit-time tubes, e.g. klystrons, travelling-wave tubes, magnetrons
- H01J25/50—Magnetrons, i.e. tubes with a magnet system producing an H-field crossing the E-field
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J2223/00—Details of transit-time tubes of the types covered by group H01J2225/00
- H01J2223/02—Electrodes; Magnetic control means; Screens
- H01J2223/04—Cathodes
- H01J2223/05—Cathodes having a cylindrical emissive surface, e.g. cathodes for magnetrons
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J2225/00—Transit-time tubes, e.g. Klystrons, travelling-wave tubes, magnetrons
- H01J2225/50—Magnetrons, i.e. tubes with a magnet system producing an H-field crossing the E-field
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Abstract
A method for preparing a cathode for a magnetron, the method comprising the steps of: (1) sleeving the processed spiral tungsten wire on a cylindrical inner container, uniformly coating an aluminum oxide suspension on the surface of the spiral tungsten wire sleeved with the inner container, drying the spiral tungsten wire in a dryer after each coating, repeating the operation until the thickness of the aluminum oxide layer exceeds the diameter of the spiral tungsten wire, taking out the inner container, and finally putting the inner container into a high-temperature hydrogen furnace for sintering to obtain a heater with good insulating property; (2) uniformly spraying a tungsten powder layer on the surface of the thermite by using a high-pressure spray gun, repeatedly spraying and drying, and then putting into a high-temperature hydrogen furnace for sintering to form a tungsten sponge layer; (3) and (3) uniformly spraying electron emission active substances on the surface of the tungsten sponge layer by using a high-pressure spray gun, repeatedly spraying and drying, and then putting into a high-temperature vacuum furnace to sinter to form a ceramic layer, thus preparing the cathode for the magnetron. The cathode prepared by the invention has the advantages of low working temperature, small evaporation, good poisoning resistance and strong electron bombardment resistance.
Description
Technical Field
The invention relates to a preparation method of a cathode for a magnetron.
Background
A magnetron is an electric vacuum device used to generate microwave energy. The tube is a vacuum diode placed in a constant magnetic field, electrons in the tube interact with a high-frequency electromagnetic field under the control of the constant magnetic field and the constant electric field which are perpendicular to each other, and energy obtained from the constant electric field can be converted into microwave energy, so that the aim of generating the microwave energy is fulfilled. Currently, magnetrons have proven to be the most efficient and economical microwave generator for industrial use as a vacuum electronic device. The cathode is one of the heart parts of the magnetron, and the quality of the cathode directly influences the output power and the service life of the magnetron; in the normal working process of the high-power magnetron, the cathode of the high-power magnetron works at a higher temperature and in a worse working environment, the surface of the cathode is bombarded by violent electrons and ions, and the traditional oxide cathode and the barium-tungsten cathode can lose effectiveness.
Disclosure of Invention
The invention aims to provide a method for preparing a cathode for a magnetron, which solves the problems that the conventional high-power magnetron works at a higher temperature and in a worse working environment, the surface of the cathode is bombarded by violent electrons and ions, and the conventional oxide cathode and the conventional barium-tungsten cathode fail in the normal working process.
In order to achieve the above object, the technical scheme is that the preparation method of the cathode for the magnetron comprises the following steps:
(1) sleeving the processed spiral tungsten wire on a cylindrical inner container, uniformly coating an aluminum oxide suspension on the surface of the spiral tungsten wire sleeved with the inner container, drying the spiral tungsten wire in a dryer after each coating, repeating the operation until the thickness of the aluminum oxide layer exceeds the diameter of the spiral tungsten wire, taking out the inner container, and finally putting the inner container into a high-temperature hydrogen furnace for sintering to obtain a heater with good insulating property;
(2) uniformly spraying a tungsten powder layer on the surface of the thermite by using a high-pressure spray gun, repeatedly spraying and drying, and then putting into a high-temperature hydrogen furnace for sintering to form a tungsten sponge layer;
(3) and (3) uniformly spraying electron emission active substances on the surface of the tungsten sponge layer by using a high-pressure spray gun, repeatedly spraying and drying, and then putting into a high-temperature vacuum furnace to sinter to form a ceramic layer, thus preparing the cathode for the magnetron.
Advantageous effects
Compared with the prior art, the invention has the following advantages.
1. The cathode prepared by the invention has the advantages of low working temperature, small evaporation, good poisoning resistance and strong electron bombardment resistance;
2. the invention has simple manufacturing process and lower cost and has better application potential in a high-power magnetron.
Drawings
The invention is further described below with reference to the accompanying drawings.
FIG. 1 is a flow chart of the cathode preparation of the present invention;
FIG. 2 is a schematic view of the spiral tungsten filament and the inner container of the present invention;
FIG. 3 is EDS spectrum of yttrium zirconate cathode prepared in the first embodiment of the present invention
FIG. 4 is a cross-sectional view of the overall structure of a yttrium zirconate cathode fabricated according to a first embodiment of the present invention;
FIG. 5 is a thermal emission I-V characteristic curve of a yttrium zirconate cathode prepared according to a first embodiment of the invention;
FIG. 6 is a graph of the life characteristics of a yttrium zirconate cathode prepared in accordance with example one of the present invention;
FIG. 7 is an EDS spectrum of a gadolinium hafnate cathode prepared in example two of the present invention;
fig. 8 is a cross-sectional view of the overall structure of a gadolinium hafnate cathode according to a second embodiment of the present invention;
FIG. 9 is a thermal emission I-V characteristic curve of a gadolinium hafnate cathode prepared according to a second embodiment of the present invention;
FIG. 10 is a graph illustrating lifetime characteristics of a gadolinium hafnate cathode prepared according to example two of the present invention;
FIG. 11 is an EDS spectrum of a yttrium hafnate cathode prepared in example three of the present invention;
FIG. 12 is a sectional view showing the overall structure of a yttrium hafnate cathode according to a third embodiment of the present invention;
FIG. 13 is a thermal emission I-V characteristic curve of a yttrium hafnate cathode prepared according to a third embodiment of the present invention;
fig. 14 is a graph showing the lifetime characteristics of a yttrium hafnate cathode prepared according to example three of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to specific embodiments and accompanying drawings.
A method for preparing a cathode for a magnetron, as shown in fig. 1 and 2, the method comprising the steps of:
(4) sleeving the processed spiral tungsten wire on a cylindrical inner container, uniformly coating an aluminum oxide suspension on the surface of the spiral tungsten wire sleeved with the inner container, drying the spiral tungsten wire in a dryer after each coating, repeating the operation until the thickness of the aluminum oxide layer exceeds the diameter of the spiral tungsten wire, taking out the inner container, and finally putting the inner container into a high-temperature hydrogen furnace for sintering to obtain a heater with good insulating property;
(5) uniformly spraying a tungsten powder layer on the surface of the thermite by using a high-pressure spray gun, repeatedly spraying and drying, and then putting into a high-temperature hydrogen furnace for sintering to form a tungsten sponge layer;
(6) and (3) uniformly spraying electron emission active substances on the surface of the tungsten sponge layer by using a high-pressure spray gun, repeatedly spraying and drying, and then putting into a high-temperature vacuum furnace to sinter to form a ceramic layer, thus preparing the cathode for the magnetron.
The alumina suspension in the step (1) is a mixed solution of 20wt% of alumina powder, 10wt% of (1 ~ 3)% methanol solution and 70wt% of (1 ~ 3)% nitro-cotton solution, wherein the purity of the alumina powder is 4N, the average grain diameter is less than 1 mu m, the wire diameter of the spiral tungsten wire is 1.2 ~ 1.4mm, the spiral diameter is 8.5 ~ 8.7.7 mm, and the spiral length is 23 ~ 27 mm.
The sintering process of the high-temperature hydrogen furnace in the step (1) comprises the steps of linearly raising the temperature to 1450 ~ 1800 ℃ from the normal temperature within 2 ~ 20 minutes, preserving the temperature for 10 ~ 30 minutes, and linearly lowering the temperature to the normal temperature within 2 ~ 12 hours to obtain the thermite with good insulating property.
The thickness of the tungsten powder layer repeatedly sprayed and dried in the step (2) is 20 ~ 200 microns, the purity of the tungsten powder is 4N, the particle size is 1 ~ 2 microns, the air pressure value adopted by a high-pressure spray gun for spraying the tungsten powder layer is 0.4 ~ 0.8.8 Mpa, the tungsten powder layer is dried by a dryer after being sprayed once, and the operation is repeated until the tungsten powder layer is of a certain thickness.
The sintering process of the high-temperature hydrogen furnace in the step (2) comprises the steps of linearly raising the temperature to 1500 ~ 2000 ℃ from the normal temperature within 0.5 ~ 2 hours, preserving the temperature for 0.5 ~ 2 hours, and linearly lowering the temperature to the normal temperature within 2 ~ 12 hours to obtain the tungsten sponge layer.
The electron emission active material in the step (3) is one of a yttrium zirconate suspension, a gadolinium hafnate suspension and a yttrium hafnate suspension, wherein the yttrium zirconate suspension is a mixed solution of 20wt% of yttrium zirconate powder and 80wt% of (1 ~ 3)% of nitrocotton solution, the gadolinium hafnate suspension is a mixed solution of 20wt% of gadolinium hafnate powder and 80wt% of (1 ~ 3)% of nitrocotton solution, the yttrium hafnate suspension is a mixed solution of 20wt% of yttrium hafnate powder and 80wt% of (1 ~ 3)% of nitrocotton solution, a high-pressure spray gun for spraying the electron emission active material has a pressure value of 0.5 ~ 1.0.0 Mpa, and after each time of spraying the electron emission active material, the high-pressure spray gun is dried by using a dryer, and the operation is repeated until a certain thickness is achieved.
The sintering process in the high-temperature vacuum furnace in the step (3) comprises the steps of firstly linearly increasing the temperature from the normal temperature to 1400 ~ 1800 ℃ within 2 ~ 4 hours, preserving the temperature for 2 ~ 7 hours, and then linearly decreasing the temperature to the normal temperature within 12 ~ 24 hours to obtain the ceramic layer, wherein the vacuum degree in the sintering process is always superior to 10-5Pa, and the thickness of the final sintered ceramic layer is 50 ~ 300 μm.
Example one
Yttrium zirconate is used as the electron-emitting active substance.
Sleeving a spiral tungsten wire with the wire diameter of 1.2 ~.4 mm, the spiral diameter of Ø of 8.5 Ø 08.7mm and the spiral length L of 23 Ø mm on a cylindrical liner, uniformly coating an aluminum oxide suspension on the surface of the spiral tungsten wire sleeved with the liner, wherein the suspension is a mixed solution of 20wt% of aluminum oxide powder, 10wt% of (1 Ø) methanol solution and 70wt% of (1 Ø) nitro-cotton solution, wherein the purity of the aluminum oxide powder is 4N and the average particle size is less than 1 μm, drying the suspension in a dryer after each coating until the thickness of the coated aluminum oxide layer exceeds the diameter of the spiral tungsten wire, taking out the liner, sintering the liner in a high-temperature hydrogen furnace, wherein the process is that the temperature is raised linearly from a normal temperature of 2 89420 minutes to 1450 9651800 ℃ for 10 Ø minutes, the time is maintained for 2 hours, the time is lowered to the normal temperature, the temperature is taken out, the high-pressure tungsten powder spray gun is used for spraying the suspension on the surface of a high-pressure tungsten powder spray gun, the surface of a high-pressure spray gun, the high-pressure-spray gun is used for spraying the tungsten powder, the tungsten powder is sprayed on the surface of a high-spray gun, the tungsten powder spray gun, the tungsten powder is sprayed on the tungsten powder, the tungsten powder is sprayed on the tungsten powder, the tungsten powder is uniformly sprayed on the tungsten powder, the tungsten powder is sprayed on the tungsten powder, the tungsten powder is sprayed on the tungsten powder, the-5Pa, the sintering process comprises the steps of linearly increasing the temperature from the normal temperature for 2 ~ 4 hours to 1400 ~ 1800 ℃ and preserving the temperature for 2 ~ 7 hours, and then linearly decreasing the temperature to the normal temperature for 12 ~ 24 hours, thus obtaining the compact and uniform zirconic acidThe yttrium ceramic layer is an EDS spectrum of yttrium zirconate ceramic as shown in figure 3, the thickness of the prepared yttrium zirconate ceramic layer is 50 ~ 300 μm, the novel yttrium zirconate cathode for the magnetron is prepared through the preparation process, the sectional view of the whole structure of the yttrium zirconate cathode for the magnetron is shown in figure 4, the yttrium zirconate cathode for the magnetron has larger emission capacity, and 1.3A/cm can be obtained at the working temperature of 1600 ℃ and under the anode voltage of 300V2As shown in fig. 5; in addition, on a life test bed, the yttrium zirconate cathode for the magnetron of the invention has the anode voltage of 220V at 1500 ℃, and the thermal emission current density of 0.5A/cm2Under the condition, as shown in fig. 6, the service life can reach more than 5000 hours, which is far higher than the 1000-hour service life requirement of the magnetron cathode in actual production.
Example two
Gadolinium hafnate is used as the electron-emitting active substance.
Sleeving a spiral tungsten wire with the wire diameter of 1.2 ~ 1.4mm, the spiral diameter of Ø of 8.5 Ø 08.7mm and the spiral length L of 23 Ø mm on a cylindrical liner, uniformly coating a suspension of 20wt% of aluminum oxide powder, 10wt% of (1 Ø)% of methanol solution and 70wt% of (1 ~)% of nitrocotton solution on the surface of the spiral tungsten wire sleeved with the liner, wherein the purity of the aluminum oxide powder is 4N, the average particle size is less than 1 mu m, drying the suspension under a dryer after coating once, repeating the operation until the thickness of the coated aluminum oxide layer exceeds the diameter of the tungsten spiral wire, taking out the liner, sintering the liner in a high-temperature hydrogen furnace, wherein the process is that the temperature is linearly increased from the normal temperature of 2 ~ minutes to 1450 ~ ℃ for 10 ~ minutes, the time is consumed by 2 ~ hours, the temperature is linearly decreased to the normal temperature, taking out to obtain the tungsten powder with good insulation performance, spraying the tungsten powder on the surface of a high-pressure spray gun by using a high-pressure spray gun, spraying the tungsten powder on the surface of the tungsten wire by using a high-pressure spray gun, wherein the tungsten powder is sprayed on the tungsten wire with the tungsten powder, the tungsten wire, the tungsten powder is sprayed on the tungsten powder, theFirstly, linearly raising the temperature from the normal temperature for 0.5 ~ 2 hours to 1500 ~ 2000 ℃, preserving the temperature for 0.5 ~ 2 hours, then linearly reducing the temperature to the normal temperature for 2 ~ 12 hours to obtain a tungsten sponge layer, then uniformly spraying gadolinium hafnate suspension with a certain thickness on the surface of the tungsten sponge layer by using a high-pressure spray gun, wherein the gadolinium hafnate suspension is a mixed solution of 20wt% gadolinium hafnate powder and 80wt% of (1 ~ 3)% nitrocotton solution, the air pressure value of the spray gun is 0.5 ~ 1.0.0 MPa, drying by using a drying machine after spraying the gadolinium hafnate suspension once, then repeating the operation until the certain thickness, finally placing the mixture into a high-temperature vacuum furnace for sintering, and the vacuum degree of the vacuum furnace in the whole sintering process is always better than 10-5Pa, the sintering process comprises the steps of linearly increasing the temperature to 1400-1400 ~ 1800 ℃ from 2 ~ 4 hours consumed at the normal temperature, preserving the temperature for 2 ~ 7 hours, then linearly reducing the temperature to the normal temperature for 12-12 ~ 24 hours, thus obtaining a compact and uniform gadolinium hafnate ceramic layer, the EDS spectrogram of the gadolinium hafnate ceramic shown in figure 7 is obtained, the thickness of the prepared gadolinium hafnate ceramic layer is 50 ~ 300 mu m, the novel gadolinium hafnate cathode for the magnetron is obtained through the preparation process, and the sectional view of the whole structure of the gadolinium hafnate cathode for the magnetron is shown in figure 8, the gadolinium hafnate cathode for the magnetron has large emission capacity, and can obtain 2A/cm at the working temperature of 1600 ℃ and under the anode voltage of 300V2As shown in fig. 9. In addition, on a life test bed, the gadolinium hafnate cathode for the magnetron of the invention has the anode voltage of 160V and the thermal emission current density of 0.5A/cm at 1500 DEG C2Under the condition, as shown in fig. 10, the service life can reach more than 5000 hours, which is far higher than the 1000-hour service life requirement of the magnetron cathode in the actual production.
EXAMPLE III
Yttrium hafnate is used as the electron-emitting active substance.
Sleeving a spiral tungsten wire with the wire diameter of 1.2 ~ 1.4.4 mm, the spiral diameter of Ø of 8.5 ~ 8.7.7 mm and the spiral length L of 23 ~ 27mm on a cylindrical liner, then uniformly coating an aluminum oxide suspension on the surface of the spiral tungsten wire sleeved with the liner, wherein the suspension is a mixed solution of 20wt% of aluminum trioxide powder, 10wt% of (1 ~ 3)% methanol solution and 70wt% of (1 ~ 3)% nitrocotton solution, the purity of the aluminum trioxide powder is 4N,the average grain size is less than 1 mu m, the coating is carried out once and then the drying is carried out under a dryer, the operation is repeated until the thickness of the coated aluminum oxide layer exceeds the diameter of a tungsten spiral wire, the inner container is taken out and put into a high-temperature hydrogen furnace for sintering, the process comprises the steps of linearly increasing the temperature to 1450 ~ ℃ from the normal temperature after 2 minutes and 20 minutes are consumed, keeping the temperature for 10 ~ minutes, then linearly reducing the temperature to the normal temperature after 2 hours and 2 ~ hours are consumed, the thermion with good insulation performance is obtained, then a tungsten powder layer with a certain thickness is evenly sprayed on the surface of the thermion by a high-pressure spray gun, wherein the purity of the tungsten powder is 4N, the grain size is 1 ~ mu m, the air pressure value adopted by the high-pressure spray gun is 0.4 ~.8 MPa, the drying is carried out once after the tungsten powder is sprayed, the operation is repeated until the thickness is a certain thickness, the thickness of the repeatedly sprayed dried tungsten powder layer is 20 ~ mu m, finally, the tungsten wire with the tungsten powder layer sprayed on the surface is put into the high-temperature hydrogen furnace for sintering, the process comprises the steps of firstly, the steps of linearly increasing the linear spraying the time from the normal-temperature from 0. ~ hours to 2 hours and 2 hours from the normal temperature after the tungsten powder is 0. ~ hours, the tungsten powder, the high-pressure spray gun is carried out, the high-pressure spray gun is carried out, the process of the linear spraying of the high-pressure spray gun, the high-pressure spray gun-5Pa, the sintering process comprises the steps of linearly increasing the temperature from the normal temperature for 2 ~ 4 hours to 1400 ~ 1800 ℃ and preserving the temperature for 2 ~ 7 hours, then linearly decreasing the temperature to the normal temperature for 12 ~ 24 hours, so as to obtain a compact and uniform yttrium hafnate ceramic layer, wherein an EDS spectrogram of the yttrium hafnate ceramic is shown in figure 11, the thickness of the prepared yttrium hafnate ceramic layer is 50 ~ 300 mu m, the novel yttrium hafnate cathode for the magnetron is prepared through the preparation process, and the overall structural cross-section of the yttrium hafnate cathode for the magnetron is shown in figure 122As shown in fig. 13. In addition, in the life testOn the test table, the yttrium hafnate cathode for the magnetron of the invention has the anode voltage of 300V at 1450 ℃, and the thermal emission current density of 1A/cm2Under the condition, as shown in fig. 14, the service life can reach more than 5000 hours, which is far higher than the 1000-hour service life requirement of the magnetron cathode in actual production.
Claims (7)
1. A method for preparing a cathode for a magnetron, the method comprising the steps of:
sleeving the processed spiral tungsten wire on a cylindrical inner container, uniformly coating an aluminum oxide suspension on the surface of the spiral tungsten wire sleeved with the inner container, drying the spiral tungsten wire in a dryer after each coating, repeating the operation until the thickness of the aluminum oxide layer exceeds the diameter of the spiral tungsten wire, taking out the inner container, and finally putting the inner container into a high-temperature hydrogen furnace for sintering to obtain a heater with good insulating property;
uniformly spraying a tungsten powder layer on the surface of the thermite by using a high-pressure spray gun, repeatedly spraying and drying, and then putting into a high-temperature hydrogen furnace for sintering to form a tungsten sponge layer;
and (3) uniformly spraying electron emission active substances on the surface of the tungsten sponge layer by using a high-pressure spray gun, repeatedly spraying and drying, and then putting into a high-temperature vacuum furnace to sinter to form a ceramic layer, thus preparing the cathode for the magnetron.
2. The method of claim 1, wherein the alumina suspension of step (1) is a mixture of 20wt% alumina powder, 10wt% methanol solution (1 ~ 3) and 70wt% nitro-cotton solution (1 ~ 3), wherein the alumina powder has a purity of 4N and an average diameter of less than 1 μm, and the spiral tungsten filament has a filament diameter of 1.2 ~ 1.4.4 mm, a spiral diameter of 8.5 ~ 8.7.7 mm, and a spiral length of 8623 mm and 23 ~ 27 mm.
3. The method of claim 1, wherein the sintering process in the high temperature hydrogen furnace in step (1) comprises the steps of heating linearly from room temperature to 1450 ~ 1800 ℃ over 2 ~ 20 minutes, maintaining the temperature for 10 ~ 30 minutes, and then cooling linearly to room temperature over 2 ~ 12 hours to obtain the thermite with good insulating property.
4. The method of claim 1, wherein the repeatedly spraying and drying step (2) is performed so that the thickness of the tungsten powder layer is 20 ~ 200 μm, the purity of the tungsten powder is 4N, the particle size is 1 ~ 2 μm, the pressure of the high pressure spray gun used for spraying the tungsten powder layer is 0.4 ~ 0.8.8 Mpa, the tungsten powder layer is dried by a dryer after each spraying, and the above operations are repeated until the tungsten powder layer has a certain thickness.
5. The method of claim 1, wherein the sintering process in the high temperature hydrogen furnace in step (2) comprises linearly raising the temperature from room temperature to 1500 ~ 2000 ℃ over 0.5 ~ 2 hours, maintaining the temperature for 0.5 ~ 2 hours, and linearly lowering the temperature to room temperature over 2 ~ 12 hours to obtain the tungsten sponge layer.
6. The method of claim 1, wherein the electron emission active material in the step (3) is one of a yttrium zirconate suspension, a gadolinium hafnate suspension, and a yttrium hafnate suspension, wherein the yttrium zirconate suspension is a mixture of 20wt% yttrium zirconate powder and 80wt% nitro-cotton solution (1 ~ 3)% and the gadolinium hafnate suspension is a mixture of 20wt% gadolinium hafnate powder and 80wt% nitro-cotton solution (1 ~ 3)% and the yttrium hafnate suspension is a mixture of 20wt% yttrium hafnate powder and 80wt% nitro-cotton solution (1 ~ 3)% and the pressure applied to the high pressure of the spray gun for spraying the electron emission active material is 0.5 ~ 1.0.0 Mpa and the spray gun is dried by a dryer after spraying the electron emission active material once and the above operation is repeated until a certain thickness is reached.
7. The method of claim 1, wherein the sintering process in the high temperature vacuum furnace in step (3) is performed by first linearly raising the temperature from room temperature for 2 ~ 4 hours to 1400 ~ 1800 ℃ and maintaining the temperature for 2 ~ 7 hoursThe ceramic layer is obtained after the temperature is linearly reduced to the normal temperature within 12 ~ 24 hours, and the vacuum degree in the sintering process is always superior to 10-5Pa, and the thickness of the final sintered ceramic layer is 50 ~ 300 μm.
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Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2749470A (en) * | 1952-06-11 | 1956-06-05 | Int Standard Electric Corp | Indirectly heated cathodes |
GB1012695A (en) * | 1962-10-15 | 1965-12-08 | Philips Electronic Associated | Improvements in indirectly-heated electron-tube cathodes |
US3246197A (en) * | 1962-10-02 | 1966-04-12 | Westinghouse Electric Corp | Cathode heater having an aluminum oxide and tungesten coating |
JPS50120561A (en) * | 1974-02-22 | 1975-09-20 | ||
JPS5693246A (en) * | 1979-12-27 | 1981-07-28 | Toshiba Corp | Production of magnetron cathode body |
JPS6340230A (en) * | 1986-08-05 | 1988-02-20 | Toshiba Corp | Manufacture of heater of indirectly heated cathode |
JPH01279537A (en) * | 1988-04-30 | 1989-11-09 | Futaba Corp | Indirectly heated linear cathode |
CN1052748A (en) * | 1989-12-22 | 1991-07-03 | 国营国光电子管总厂 | Magnetron cathode assembly and manufacture craft |
CN1925088A (en) * | 2005-08-31 | 2007-03-07 | 安徽华东光电技术研究所 | Dipped barium wolfram cathode and process for its manufacture |
CN101687247A (en) * | 2007-07-24 | 2010-03-31 | 株式会社东芝 | Method for manufacturing coil member and coil member |
CN107622931A (en) * | 2016-07-14 | 2018-01-23 | 中国科学院电子学研究所 | A kind of electron gun and gyrotron |
CN109037007A (en) * | 2018-07-03 | 2018-12-18 | 九江学院 | A kind of preparation method of the directly-heated type cathode of resistance to electron bombardment |
CN109065422A (en) * | 2018-07-03 | 2018-12-21 | 九江学院 | A kind of preparation method of directly-heated type carbonization tungsten-rhenium alloy cathode |
-
2019
- 2019-09-16 CN CN201910870422.7A patent/CN110676137B/en active Active
Patent Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2749470A (en) * | 1952-06-11 | 1956-06-05 | Int Standard Electric Corp | Indirectly heated cathodes |
US3246197A (en) * | 1962-10-02 | 1966-04-12 | Westinghouse Electric Corp | Cathode heater having an aluminum oxide and tungesten coating |
GB1012695A (en) * | 1962-10-15 | 1965-12-08 | Philips Electronic Associated | Improvements in indirectly-heated electron-tube cathodes |
JPS50120561A (en) * | 1974-02-22 | 1975-09-20 | ||
JPS5693246A (en) * | 1979-12-27 | 1981-07-28 | Toshiba Corp | Production of magnetron cathode body |
JPS6340230A (en) * | 1986-08-05 | 1988-02-20 | Toshiba Corp | Manufacture of heater of indirectly heated cathode |
JPH01279537A (en) * | 1988-04-30 | 1989-11-09 | Futaba Corp | Indirectly heated linear cathode |
CN1052748A (en) * | 1989-12-22 | 1991-07-03 | 国营国光电子管总厂 | Magnetron cathode assembly and manufacture craft |
CN1925088A (en) * | 2005-08-31 | 2007-03-07 | 安徽华东光电技术研究所 | Dipped barium wolfram cathode and process for its manufacture |
CN101687247A (en) * | 2007-07-24 | 2010-03-31 | 株式会社东芝 | Method for manufacturing coil member and coil member |
CN107622931A (en) * | 2016-07-14 | 2018-01-23 | 中国科学院电子学研究所 | A kind of electron gun and gyrotron |
CN109037007A (en) * | 2018-07-03 | 2018-12-18 | 九江学院 | A kind of preparation method of the directly-heated type cathode of resistance to electron bombardment |
CN109065422A (en) * | 2018-07-03 | 2018-12-21 | 九江学院 | A kind of preparation method of directly-heated type carbonization tungsten-rhenium alloy cathode |
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