WO2018036068A1 - 碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法 - Google Patents

碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法 Download PDF

Info

Publication number
WO2018036068A1
WO2018036068A1 PCT/CN2016/113406 CN2016113406W WO2018036068A1 WO 2018036068 A1 WO2018036068 A1 WO 2018036068A1 CN 2016113406 W CN2016113406 W CN 2016113406W WO 2018036068 A1 WO2018036068 A1 WO 2018036068A1
Authority
WO
WIPO (PCT)
Prior art keywords
doped
cathode
carbonized
temperature
cathode material
Prior art date
Application number
PCT/CN2016/113406
Other languages
English (en)
French (fr)
Inventor
王金淑
董丽然
张�杰
田明创
刘伟
周美玲
左铁镛
Original Assignee
北京工业大学
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 北京工业大学 filed Critical 北京工业大学
Priority to US15/757,343 priority Critical patent/US10388484B2/en
Publication of WO2018036068A1 publication Critical patent/WO2018036068A1/zh

Links

Images

Classifications

    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/24—After-treatment of workpieces or articles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
    • B22F5/12—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product of wires
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C32/00—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ
    • C22C32/001—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides
    • C22C32/0015—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides with only single oxides as main non-metallic constituents
    • C22C32/0031—Matrix based on refractory metals, W, Mo, Nb, Hf, Ta, Zr, Ti, V or alloys thereof
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
    • C23C8/20—Carburising
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/80—After-treatment
    • 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
    • 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
    • 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
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/24—After-treatment of workpieces or articles
    • B22F2003/241—Chemical after-treatment on the surface
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2301/00—Metallic composition of the powder or its coating
    • B22F2301/20—Refractory metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2302/00—Metal Compound, non-Metallic compound or non-metal composition of the powder or its coating
    • B22F2302/25—Oxide
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
    • B22F2998/10—Processes characterised by the sequence of their steps
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2999/00—Aspects linked to processes or compositions used in powder metallurgy
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B2206/00—Aspects relating to heating by electric, magnetic, or electromagnetic fields covered by group H05B6/00
    • H05B2206/04—Heating using microwaves
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/64—Heating using microwaves
    • H05B6/66—Circuits
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making

Definitions

  • ThO 2 -W cathode materials are widely used in magnetron tubes for household microwave ovens, but Th is a radioactive element that causes radioactive hazards to workers producing ThO 2 -W filaments, which also makes discarded ThO 2 -W filaments. It can only be deeply buried and cannot be recycled. China's W production is declining day by day, which is contrary to the "sustainable development” advocated by China. Due to poor plastic filaments ThO 2 -W, such that the yield of ThO 2 -W wires only about 60%, so a high-shaping research, non-radioactive green cathode material is necessary.
  • the invention adopts liquid-liquid doping method to prepare La 2 O 3 and Lu 2 O 3 doped Mo powder, and the method can obtain doped molybdenum powder with uniform distribution of rare earth oxide, which is beneficial to improve uniformity and stability of cathode emission. Sex.
  • the La 2 O 3 and Lu 2 O 3 doped Mo cathode obtained by the liquid-liquid doping method can realize high-temperature carbonization and high-temperature exhaust treatment, and the two processes play a role in the emission stability of the cathode in the magnetron.
  • Critical impact When an electron bombards the surface of the cathode, it will excite secondary electrons.
  • Lu 2 O 3 ensures a sustained high emission current density after the cathode is operated, thereby ensuring the stability of the cathode emission, so that the output current of the cathode is not attenuated. Therefore, composite La 2 O 3 , Lu 2 O 3 doped Mo cathode materials were prepared. Cathode materials of this composition have not been reported at home and abroad.
  • the invention adopts a high-temperature short-time carbonization process, and obtains a carbonized cathode wire with a high degree of carbonization (carbonization degree is 10-50%), and the cathode prepared by the invention is suitable for use in a magnetron of a microwave oven.
  • the object of the present invention is to provide a composite La 2 O 3 , Lu 2 O 3 doped Mo cathode material for a magnetron and a preparation method thereof, wherein the rare earth active materials La 2 O 3 and Lu 2 O 3 in the cathode matrix improve the cathode The emission properties and emission stability of the material.
  • cathode materials suitable for use in magnetrons and having high emission performance and emission stability have rarely been reported at home and abroad.
  • the carbonized La 2 O 3 and Lu 2 O 3 composite doped Mo cathode material is characterized in that the molybdenum matrix is doped with rare earth active materials La 2 O 3 and Lu 2 O 3 , and the rare earth active material is added in a total amount of the cathode material. 2.0-5.0 wt%, the balance being molybdenum; wherein La 2 O 3 and Lu 2 O 3 are mixed in any ratio.
  • the mass ratio of La 2 O 3 to Lu 2 O 3 is: (2-5): 1, more preferably 4:1.
  • the invention provides a method for preparing a composite La 2 O 3 , Lu 2 O 3 doped Mo cathode material for a magnetron, which comprises the following steps:
  • ammonium heptamolybdate (1) mixing ammonium heptamolybdate solution, cerium nitrate solution, cerium nitrate solution and citric acid solution, wherein ammonium heptamolybdate, cerium nitrate and cerium nitrate are added according to the mass ratio of molybdenum, cerium oxide and cerium oxide in the cathode material.
  • Ammonium heptamolybdate The mass ratio of citric acid is 1: (0.8-1.5), heated in a water bath, and mechanically stirred. After the solution is formed into a gel, it is taken out, dried, and decomposed to form an oxide mixed powder; the dry gel decomposition temperature is 500-680 ° C;
  • the oxide mixed powder obtained in the step (1) is subjected to secondary reduction treatment in a hydrogen atmosphere to obtain La 2 O 3 and Lu 2 O 3 doped Mo powder, and the primary reduction temperature is 500-680 ° C, secondary reduction.
  • the temperature is 800-980 ° C;
  • La 2 O 3 , Lu 2 O 3 doped Mo powder is pressed and sintered to obtain La 2 O 3 , Lu 2 O 3 doped Mo rod, sintering temperature is 1800-2030 ° C;
  • step (4) The uncarburized La 2 O 3 and Lu 2 O 3 doped Mo cathodes in step (4) are subjected to an assembly magnetron process, and after assembly, carbonization treatment is performed, and the carbonization temperature is 1550-1900 ° C, and the heat preservation is 60. At -150 s, a carbonized La 2 O 3 , Lu 2 O 3 doped Mo cathode having a degree of carbonization of 10-50% was obtained.
  • the exhaust gas treatment process is performed, the cathode exhaust current is 10-12.5 A, the exhaust gas temperature is 1600-1900 ° C, and the heat preservation is 20-60 min.
  • the exhaust-treated tube is subjected to an activation aging process, the activation temperature is 1450-1650 ° C, and the temperature is maintained for 10-30 min; the tube after activation and aging treatment is assembled into a magnetron.
  • the cathode of the present invention has an operating temperature of 1200 to 1400 °C.
  • the carbonized La 2 O 3 and Lu 2 O 3 composite doped Mo cathode material prepared by the invention has good thermal electron emission performance and good emission stability after being charged into the magnetron.
  • the test result of the magnetron DC emission performance is ⁇ 640mA, which is ⁇ 2 times of the ThO 2 -W cathode ( ⁇ 330mA) under the same test conditions.
  • the cathode is assembled into a microwave oven and can work stably for more than 500 hours, and the power of the microwave oven is not attenuated. Meet the requirements of the microwave oven.
  • Example 1 is a graph showing the output power of a microwave oven after the La 2 O 3 and Lu 2 O 3 doped Mo cathode obtained in Example 5 were placed in a microwave oven.
  • the decomposed powder is reduced under a hydrogen atmosphere, the primary reduction temperature is 550 ° C, the secondary reduction temperature is 980 ° C, and the rare earth oxide doped molybdenum powder is obtained by cooling with the furnace; the isostatic pressing type process is adopted, and the pressing pressure is adopted.
  • the pressure was 150 MPa and the pressure was kept for 15 min; the green body was sintered under a hydrogen atmosphere, and the sintering temperature was 1800 ° C to obtain a rare earth oxide doped molybdenum cathode rod.
  • spin-baking, drawing, cleaning, straightening, winding, shaping, and cutting processes are performed to obtain an uncarbonized La 2 O 3 , Lu 2 O 3 doped Mo cathode.
  • the uncarburized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were subjected to an assembly magnetron process, and then carbonized after assembly.
  • the carbonization temperature was 1800 ° C and the temperature was maintained for 70 s to obtain a carbonized La 2 having a carbonization degree of 32.3%.
  • O 3 , Lu 2 O 3 doped Mo cathode After the obtained carbonized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were assembled, an unvented electron tube was obtained, and the electron tube was subjected to an exhaust treatment process, and the cathode exhaust temperature was 1800 ° C and the temperature was kept for 30 minutes.
  • the exhausted treated tube is subjected to an activation aging process, the activation temperature is 1600 ° C, and the temperature is maintained for 30 min.
  • the DC emission characteristics of the test tubes are listed in Table 1.
  • the tube after activation and aging treatment is assembled into a magnetron.
  • the operating temperature of the cathode was 1250 °C.
  • the output power of the microwave oven was then tested.
  • Example 2 A cathode having a rare earth oxide addition amount of 2.5 wt% was prepared, and the balance was molybdenum.
  • An aqueous solution of 1794.2 g of ammonium heptamolybdate tetrahydrate, an aqueous solution of 53.16 g of cerium nitrate, an aqueous solution of 11.79 g of cerium nitrate, and a solution of citric acid of 1859 g were mixed, and stirred in a water bath to obtain a wet gel, which was dried and decomposed at 550 ° C.
  • the decomposed powder is reduced under a hydrogen atmosphere, the primary reduction temperature is 550 ° C, the secondary reduction temperature is 950 ° C, and the rare earth oxide doped molybdenum powder is obtained by cooling with the furnace; the isostatic pressing type process is adopted, and the pressing pressure is adopted.
  • the pressure was 150 MPa and the pressure was kept for 15 min; the green body was sintered under a hydrogen atmosphere, and the sintering temperature was 1800 ° C to obtain a rare earth oxide doped molybdenum cathode rod.
  • spin-baking, drawing, cleaning, straightening, winding, shaping, and cutting processes are performed to obtain an uncarbonized La 2 O 3 , Lu 2 O 3 doped Mo cathode.
  • the uncarburized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were subjected to an assembly magnetron process, and then carbonized after assembly.
  • the carbonization temperature was 1800 ° C and the temperature was maintained for 70 s to obtain a carbonized La 2 having a carbonization degree of 34.1%.
  • O 3 , Lu 2 O 3 doped Mo cathode After the obtained carbonized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were assembled, an unvented electron tube was obtained, and the electron tube was subjected to an exhaust treatment process, and the cathode exhaust temperature was 1800 ° C and the temperature was kept for 30 minutes.
  • the exhausted treated tube is subjected to an activation aging process, the activation temperature is 1600 ° C, and the temperature is maintained for 30 min.
  • the DC emission characteristics of the test tubes are listed in Table 1.
  • the tube after activation and aging treatment is assembled into a magnetron.
  • the operating temperature of the cathode was 1250 °C.
  • the output power of the microwave oven was then tested.
  • Example 3 A cathode having a rare earth oxide addition amount of 3 wt% was prepared, and the balance was molybdenum. 1785.0 g of an aqueous solution of ammonium heptamolybdate tetrahydrate, an aqueous solution of 63.79 g of lanthanum nitrate, an aqueous solution of 14.15 g of lanthanum nitrate, and 1862.9 g of a citric acid solution were mixed, and stirred in a water bath to obtain a wet gel, which was dried and decomposed at 550 ° C.
  • the decomposed powder is reduced under a hydrogen atmosphere, the primary reduction temperature is 550 ° C, the secondary reduction temperature is 950 ° C, and the rare earth oxide doped molybdenum powder is obtained by cooling with the furnace; the isostatic pressing type process is adopted, and the pressing pressure is adopted. It is 150 MPa, and the pressure is maintained for 15 min; the green body is sintered under a hydrogen atmosphere, and the sintering temperature is 1850 ° C to obtain a rare earth oxide doped molybdenum cathode rod. Subsequently, spin-baking, drawing, cleaning, straightening, winding, shaping, and cutting processes are performed to obtain an uncarbonized La 2 O 3 , Lu 2 O 3 doped Mo cathode.
  • the uncarburized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were subjected to assembly magnetron process, and then carbonized after assembly.
  • the carbonization temperature was 1700 ° C and the temperature was maintained for 75 s to obtain a carbonized La 2 having a carbonization degree of 28.2%.
  • O 3 , Lu 2 O 3 doped Mo cathode After the obtained carbonized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were assembled, an unvented electron tube was obtained, and the electron tube was subjected to an exhaust treatment process, and the cathode exhaust temperature was 1800 ° C and the temperature was kept for 30 minutes.
  • the exhausted treated tube is subjected to an activation aging process, the activation temperature is 1600 ° C, and the temperature is maintained for 30 min.
  • the DC emission characteristics of the test tubes are listed in Table 1.
  • the tube after activation and aging treatment is assembled into a magnetron.
  • the operating temperature of the cathode was 1250 °C.
  • the output power of the microwave oven was then tested.
  • Example 4 a cathode having a rare earth oxide addition amount of 3.5% by weight was prepared, and the balance was molybdenum. 1775.8 g of an aqueous solution of ammonium heptamolybdate tetrahydrate, 74.43 g of an aqueous solution of cerium nitrate, 16.50 g of an aqueous solution of cerium nitrate and 1866.7 g of a citric acid solution were mixed, and stirred in a water bath to obtain a wet gel, which was dried and decomposed at 600 ° C.
  • the decomposed powder is reduced under a hydrogen atmosphere, the primary reduction temperature is 600 ° C, the secondary reduction temperature is 920 ° C, and the rare earth oxide doped molybdenum powder is obtained by cooling with the furnace; the isostatic pressing type process is adopted, and the pressing pressure is adopted. It is 150 MPa, and the pressure is maintained for 15 min; the green body is sintered under a hydrogen atmosphere, and the sintering temperature is 1850 ° C to obtain a rare earth oxide doped molybdenum cathode rod. Subsequently, spin-baking, drawing, cleaning, straightening, winding, shaping, and cutting processes are performed to obtain an uncarbonized La 2 O 3 , Lu 2 O 3 doped Mo cathode.
  • the uncarburized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were subjected to an assembly magnetron process, and then carbonized after assembly.
  • the carbonization temperature was 1700 ° C and the temperature was maintained for 75 s to obtain a carbonized La 2 having a carbonization degree of 29.3%.
  • O 3 , Lu 2 O 3 doped Mo cathode After the obtained carbonized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were assembled, an unvented electron tube was obtained, and the electron tube was subjected to an exhaust treatment process, and the cathode exhaust temperature was 1800 ° C and the temperature was kept for 30 minutes.
  • the exhausted treated tube is subjected to an activation aging process, the activation temperature is 1600 ° C, and the temperature is maintained for 30 min.
  • the DC emission characteristics of the test tubes are listed in Table 1.
  • the tube after activation and aging treatment is assembled into a magnetron.
  • the operating temperature of the cathode was 1250 °C.
  • the output power of the microwave oven was then tested.
  • Example 5 A cathode having a rare earth oxide addition amount of 4% by weight was prepared, and the balance was molybdenum. 1766.6 g of an aqueous solution of ammonium heptamolybdate tetrahydrate, 85.06 g of an aqueous solution of cerium nitrate, 18.86 g of an aqueous solution of cerium nitrate and 1870.5 g of a citric acid solution were mixed, and stirred in a water bath to obtain a wet gel, which was dried and decomposed at 600 ° C.
  • the decomposed powder is reduced under a hydrogen atmosphere, the primary reduction temperature is 600 ° C, the secondary reduction temperature is 900 ° C, and the rare earth oxide doped molybdenum powder is obtained by cooling with the furnace; the isostatic pressing type process is adopted, and the pressing pressure is adopted. It is 150 MPa and held for 15 min; the green body is sintered under a hydrogen atmosphere, and the sintering temperature is 1900 ° C to obtain a rare earth oxide doped molybdenum cathode rod. Subsequently, spin-baking, drawing, cleaning, straightening, winding, shaping, and cutting processes are performed to obtain an uncarbonized La 2 O 3 , Lu 2 O 3 doped Mo cathode.
  • the uncarburized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were assembled into a magnetron process, and then carbonized after assembly.
  • the carbonization temperature was 1600 ° C and the temperature was maintained for 80 s to obtain a carbonized La 2 having a carbonization degree of 28.2%.
  • O 3 , Lu 2 O 3 doped Mo cathode After the obtained carbonized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were assembled, an unvented electron tube was obtained, and the electron tube was subjected to an exhaust treatment process, and the cathode exhaust temperature was 1800 ° C and the temperature was kept for 30 minutes.
  • the exhausted treated tube is subjected to an activation aging process, the activation temperature is 1600 ° C, and the temperature is maintained for 30 min.
  • the DC emission characteristics of the test tubes are listed in Table 1.
  • the tube after activation and aging treatment is assembled into a magnetron.
  • the operating temperature of the cathode was 1250 °C.
  • the output power of the microwave oven was then tested.
  • Example 6 A cathode having a rare earth oxide addition amount of 4.5% by weight was prepared, and the balance was molybdenum.
  • An aqueous solution of 1757.4 g of ammonium heptamolybdate tetrahydrate, an aqueous solution of 95.69 g of lanthanum nitrate, an aqueous solution of 21.21 g of lanthanum nitrate, and 1874.3 g of a citric acid solution were mixed, and stirred in a water bath to obtain a wet gel, which was dried and decomposed at 650 ° C.
  • the decomposed powder is reduced under a hydrogen atmosphere, the primary reduction temperature is 600 ° C, the secondary reduction temperature is 980 ° C, and the rare earth oxide doped molybdenum powder is obtained by cooling with the furnace; the isostatic pressing type process is adopted, and the pressing pressure is adopted. It is 150 MPa and held for 15 min; the green body is sintered under a hydrogen atmosphere, and the sintering temperature is 1950 ° C to obtain a rare earth oxide doped molybdenum cathode rod. Subsequently, spin-baking, drawing, cleaning, straightening, winding, shaping, and cutting processes are performed to obtain an uncarbonized La 2 O 3 , Lu 2 O 3 doped Mo cathode.
  • the uncarburized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were subjected to an assembly magnetron process, and then carbonized after assembly.
  • the carbonization temperature was 1600 ° C and the temperature was maintained for 80 s to obtain a carbonized La 2 having a carbonization degree of 27.3%.
  • O 3 , Lu 2 O 3 doped Mo cathode After the obtained carbonized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were assembled, an unvented electron tube was obtained, and the electron tube was subjected to an exhaust treatment process, and the cathode exhaust temperature was 1800 ° C and the temperature was kept for 30 minutes.
  • the exhausted treated tube is subjected to an activation aging process, the activation temperature is 1600 ° C, and the temperature is maintained for 30 min.
  • the DC emission characteristics of the test tubes are listed in Table 1.
  • the tube after activation and aging treatment is assembled into a magnetron.
  • the operating temperature of the cathode was 1250 °C.
  • the output power of the microwave oven was then tested.
  • Example 7 A cathode having a rare earth oxide addition amount of 5 wt% was prepared, and the balance was molybdenum.
  • An aqueous solution of 1748.2 g of ammonium heptamolybdate tetrahydrate, an aqueous solution of 106.32 g of cerium nitrate, an aqueous solution of 23.58 g of cerium nitrate and 1878.1 g of a citric acid solution were mixed, stirred in a water bath to obtain a wet gel, and dried and decomposed at 680 °C.
  • the decomposed powder is reduced under a hydrogen atmosphere, the primary reduction temperature is 650 ° C, the secondary reduction temperature is 850 ° C, and the rare earth oxide doped molybdenum powder is obtained by cooling with the furnace; the isostatic pressing type process is adopted, and the pressing pressure is adopted. It is 150 MPa and held for 15 min; the green body is sintered under a hydrogen atmosphere, and the sintering temperature is 2000 ° C to obtain a rare earth oxide doped molybdenum cathode rod. Subsequently, spin-baking, drawing, cleaning, straightening, winding, shaping, and cutting process were performed to obtain uncarbonized La 2 O 3 and Lu 2 O 3 doped Mo cathodes.
  • the uncarburized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were subjected to an assembly magnetron process, and then carbonized after assembly.
  • the carbonization temperature was 1550 ° C, and the temperature was kept for 100 s to obtain a carbonized La 2 having a carbonization degree of 25.4%.
  • O 3 , Lu 2 O 3 doped Mo cathode After the obtained carbonized La 2 O 3 and Lu 2 O 3 doped Mo cathodes were assembled, an unvented electron tube was obtained, and the electron tube was subjected to an exhaust treatment process, and the cathode exhaust temperature was 1800 ° C and the temperature was kept for 30 minutes.
  • the exhausted treated tube is subjected to an activation aging process, the activation temperature is 1600 ° C, and the temperature is maintained for 30 min.
  • the DC emission characteristics of the test tubes are listed in Table 1.
  • the tube after activation and aging treatment is assembled into a magnetron.
  • the operating temperature of the cathode was 1250 °C.
  • the output power of the microwave oven was then tested.
  • Table 1 shows the DC emission characteristics of the tubes obtained in the respective examples.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Microwave Tubes (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)
  • Physical Vapour Deposition (AREA)

Abstract

碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法，属于稀土难熔金属阴极材料技术领域。钼基体中掺杂稀土活性物质La2O3、Lu2O3，稀土活性物质添加总量为2.0-5.0wt％。采用溶胶凝胶法制备稀土氧化物掺杂钼粉末，采用二次还原工艺，得到La2O3、Lu2O3掺杂Mo粉，经过压型和烧结得到钼棒。钼棒经旋煅、拉拔、清洗、矫直、绕制、定型、裁断工艺处理，得到未碳化的La2O3、Lu2O3掺杂Mo阴极。对阴极进行高温瞬时碳化工艺处理，得到高碳化度的碳化阴极材料。对阴极进行高温排气及激活处理工艺，得到具有良好发射性能及优异的发射稳定性的环保无放射性的阴极材料。

Description

碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法 技术领域
碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法，属于稀土难熔金属阴极材料技术领域。
背景技术
目前家用微波炉磁控管中广泛使用的是ThO2-W阴极材料，但是Th是一种放射性元素，它对生产ThO2-W丝的工人产生放射性危害，这也使得废弃的ThO2-W丝只能进行深埋处理，不能回收利用。我国W产量日渐衰减，这与我国倡导的“可持续发展”相违背。由于ThO2-W丝的塑性很差，使得ThO2-W丝的成品率只有60％左右，所以研究一种高塑形、无放射的绿色环保的阴极材料十分必要。
本发明采用液液掺杂的方法制备La2O3、Lu2O3掺杂Mo粉，该方法能够得到稀土氧化物分布均匀的掺杂钼粉，这有利于提高阴极发射的均匀性及稳定性。且经过液液掺杂方法得到的La2O3、Lu2O3掺杂Mo阴极，可以实现高温碳化及高温排气工艺处理，这两个工艺对于磁控管中阴极的发射稳定性起着至关重要的影响。当一次电子轰击阴极表面后会激发出二次电子，文章[Y2O3-Lu2O3co-doped molybdenum secondary emission material,Yang,Fan；Wang,Jinshu；Liu,Wei；Liu,Xiang；Zhou,Meiling,APPLIED SURFACE SCIENCE,270(746-750),2013。]中表明Lu2O3-Y2O3掺杂Mo阴极比单成分Y2O3掺杂Mo阴极具有更好的二次电子发射性能，说明Lu2O3具有良好的二次电子发射性能，因此添加Lu2O3可保证阴极工作后具有持续的高的发射电流密度，从而保证了阴极发射的稳定性，使得阴极的输出电流不衰减。因此本文制备了复合La2O3、Lu2O3掺杂的Mo阴极材料。该种成分的阴极材料在国内外尚未报道。
本发明采用高温短时的碳化工艺，且获得了高碳化度的碳化阴极丝材(碳化度为10-50％)，本发明制备的阴极适用于微波炉的磁控管中。
发明内容
本发明的目的是提供一种磁控管用复合La2O3、Lu2O3掺杂Mo阴极材料以及制备方法，阴极基体中的稀土活性物La2O3、Lu2O3提高了阴极材料的发射性能及发射稳定性。目前对于该种成分，适用于磁控管中，且具有很高发射性能以及发射稳定性的阴极材料在国内外鲜有报道。
碳化La2O3与Lu2O3复合掺杂Mo阴极材料，其特征在于，钼基体中掺杂稀土活性物质 La2O3、Lu2O3，稀土活性物质添加量为阴极材料总量的2.0-5.0wt％，其余为钼；其中，La2O3与Lu2O3以任意比例混合。优选La2O3与Lu2O3的质量比为：(2-5)：1，更优选4:1。
本发明所提供的磁控管用复合La2O3、Lu2O3掺杂Mo阴极材料的制备方法，其特征在于，包括以下步骤：
(1)将七钼酸铵溶液、硝酸镧溶液、硝酸镥溶液和柠檬酸溶液混合，其中七钼酸铵、硝酸镧、硝酸镥按照阴极材料中钼、氧化镧和氧化镥的质量比例添加，七钼酸铵：柠檬酸的质量比为1:(0.8-1.5)，水浴加热，机械搅拌。待溶液形成凝胶后取出，烘干，分解形成氧化物混合粉末；干凝胶分解温度为500-680℃；
(2)将步骤(1)中获得氧化物混合粉末在氢气气氛中进行二次还原处理得到La2O3、Lu2O3掺杂Mo粉末，一次还原温度为500-680℃，二次还原温度为800-980℃；
(3)将La2O3、Lu2O3掺杂Mo粉末进行压型、烧结处理，得到La2O3、Lu2O3掺杂Mo棒，烧结温度为1800-2030℃；
(4)将步骤(3)中的La2O3、Lu2O3掺杂Mo棒进行旋煅、拉拔、清洗、矫直、绕制、定型、裁断工艺处理，得到未碳化的La2O3、Lu2O3掺杂Mo阴极；
(5)将步骤(4)中的未碳化的La2O3、Lu2O3掺杂Mo阴极进行装配磁控管工艺处理，组装后进行碳化处理，碳化温度为1550-1900℃，保温60-150s，得到碳化度为10-50％的碳化La2O3、Lu2O3掺杂Mo阴极。
将得到的碳化La2O3、Lu2O3掺杂Mo阴极进行装配后，进行排气工艺处理，阴极排气电流为10-12.5A，排气温度为1600-1900℃，保温20-60min；对排气处理后的电子管进行激活老化工艺处理，激活温度为1450-1650℃，保温10-30min；将激活老化处理后的电子管组装成磁控管。
本发明所得阴极的工作温度为1200-1400℃。
上述磁控管用复合La2O3、Lu2O3掺杂Mo阴极材料适用于在微波炉磁控管中使用，尤其在稀土活性物质添加总量在3-4.5wt％的情况下。
本发明制备的碳化La2O3、Lu2O3复合掺杂Mo阴极材料，在装入磁控管后，具有良好的热电子发射性能和良好的发射稳定性。在稀土氧化物总量在4wt％时，其磁控管直流发射性能测试结果为～640mA，是在相同测试条件下ThO2-W阴极(～330mA)的～2倍。且该阴极组装到微波炉中可稳定工作500h以上，微波炉功率不衰减。满足微波炉的使用要求。
附图说明：
图1为实施例5中得到的La2O3、Lu2O3掺杂Mo阴极装入微波炉后，微波炉输出功率曲线。
具体实施方式
下面结合实施例对本发明做进一步说明，但本发明并不限于以下实施例。
实施例1制备稀土氧化物添加量为2wt％的阴极，其余为钼。将1803.5g四水合七钼酸铵的水溶液、42.53g硝酸镧的水溶液、9.43g硝酸镥的水溶液和1885g柠檬酸溶液混合，水浴搅拌得到湿凝胶，烘干、500℃分解。将分解后的粉末在氢气气氛下进行还原，一次还原温度为550℃，二次还原温度为980℃，随炉冷却得到稀土氧化物掺杂钼粉；采用等静压压型工艺，压型压力为150MPa，保压15min；坯体在氢气气氛下烧结，烧结温度为1800℃，得到稀土氧化物掺杂钼阴极棒材。随后进行旋煅、拉拔、清洗、矫直、绕制、定型、裁断工艺处理，得到未碳化的La2O3、Lu2O3掺杂Mo阴极。将未碳化的La2O3、Lu2O3掺杂Mo阴极进行装配磁控管工艺处理，组装后进行碳化处理，碳化温度为1800℃，保温70s，得到碳化度为32.3％的碳化La2O3、Lu2O3掺杂Mo阴极。将得到的碳化La2O3、Lu2O3掺杂Mo阴极进行装配后，得到未排气处理的电子管，对该电子管进行排气工艺处理，阴极排气温度为1800℃，保温30min。对排气处理后的电子管进行激活老化工艺处理，激活温度为1600℃，保温30min。测试电子管的直流发射特性，列于表1中。将激活老化处理后的电子管组装成磁控管。阴极的工作温度为1250℃。随后对微波炉的输出功率进行测试。
实施例2制备稀土氧化物添加量为2.5wt％的阴极，其余为钼。将1794.2g四水合七钼酸铵的水溶液、53.16g硝酸镧的水溶液、11.79g硝酸镥的水溶液和1859g柠檬酸溶液混合，水浴搅拌得到湿凝胶，烘干、550℃分解。将分解后的粉末在氢气气氛下进行还原，一次还原温度为550℃，二次还原温度为950℃，随炉冷却得到稀土氧化物掺杂钼粉；采用等静压压型工艺，压型压力为150MPa，保压15min；坯体在氢气气氛下烧结，烧结温度为1800℃，得到稀土氧化物掺杂钼阴极棒材。随后进行旋煅、拉拔、清洗、矫直、绕制、定型、裁断工艺处理，得到未碳化的La2O3、Lu2O3掺杂Mo阴极。将未碳化的La2O3、Lu2O3掺杂Mo阴极进行装配磁控管工艺处理，组装后进行碳化处理，碳化温度为1800℃，保温70s，得到碳化度为34.1％的碳化La2O3、Lu2O3掺杂Mo阴极。将得到的碳化La2O3、Lu2O3掺杂Mo阴极进行装配后，得到未排气处理的电子管，对该电子管进行排气工艺处理，阴极排气温度为1800℃，保温30min。对排气处理后的电子管进行激活老化工艺处理，激活温度为1600℃，保温30min。测试电子管的直流发射特性，列于表1中。将激活老化处理后的电子管组装成磁控管。阴极的工作温度为1250℃。随后对微波炉的输出功率进行测试。
实施例3制备稀土氧化物添加量为3wt％的阴极，其余为钼。将1785.0g四水合七钼酸铵的水溶液、63.79g硝酸镧的水溶液、14.15g硝酸镥的水溶液和1862.9g柠檬酸溶液混合，水浴搅拌得到湿凝胶，烘干、550℃分解。将分解后的粉末在氢气气氛下进行还原，一次还原温度为550℃，二次还原温度为950℃，随炉冷却得到稀土氧化物掺杂钼粉；采用等静压压型工艺，压型压力为150MPa，保压15min；坯体在氢气气氛下烧结，烧结温度为1850℃，得到稀土氧化物掺杂钼阴极棒材。随后进行旋煅、拉拔、清洗、矫直、绕制、定型、裁断工艺处理，得到未碳化的La2O3、Lu2O3掺杂Mo阴极。将未碳化的La2O3、Lu2O3掺杂Mo阴极进行装配磁控管工艺处理，组装后进行碳化处理，碳化温度为1700℃，保温75s，得到碳化度为28.2％的碳化La2O3、Lu2O3掺杂Mo阴极。将得到的碳化La2O3、Lu2O3掺杂Mo阴极进行装配后，得到未排气处理的电子管，对该电子管进行排气工艺处理，阴极排气温度为1800℃，保温30min。对排气处理后的电子管进行激活老化工艺处理，激活温度为1600℃，保温30min。测试电子管的直流发射特性，列于表1中。将激活老化处理后的电子管组装成磁控管。阴极的工作温度为1250℃。随后对微波炉的输出功率进行测试。
实施例4制备稀土氧化物添加量为3.5wt％的阴极，其余为钼。将1775.8g四水合七钼酸铵的水溶液、74.43g硝酸镧的水溶液、16.50g硝酸镥的水溶液和1866.7g柠檬酸溶液混合，水浴搅拌得到湿凝胶，烘干、600℃分解。将分解后的粉末在氢气气氛下进行还原，一次还原温度为600℃，二次还原温度为920℃，随炉冷却得到稀土氧化物掺杂钼粉；采用等静压压型工艺，压型压力为150MPa，保压15min；坯体在氢气气氛下烧结，烧结温度为1850℃，得到稀土氧化物掺杂钼阴极棒材。随后进行旋煅、拉拔、清洗、矫直、绕制、定型、裁断工艺处理，得到未碳化的La2O3、Lu2O3掺杂Mo阴极。将未碳化的La2O3、Lu2O3掺杂Mo阴极进行装配磁控管工艺处理，组装后进行碳化处理，碳化温度为1700℃，保温75s，得到碳化度为29.3％的碳化La2O3、Lu2O3掺杂Mo阴极。将得到的碳化La2O3、Lu2O3掺杂Mo阴极进行装配后，得到未排气处理的电子管，对该电子管进行排气工艺处理，阴极排气温度为1800℃，保温30min。对排气处理后的电子管进行激活老化工艺处理，激活温度为1600℃，保温30min。测试电子管的直流发射特性，列于表1中。将激活老化处理后的电子管组装成磁控管。阴极的工作温度为1250℃。随后对微波炉的输出功率进行测试。
实施例5制备稀土氧化物添加量为4wt％的阴极，其余为钼。将1766.6g四水合七钼酸铵的水溶液、85.06g硝酸镧的水溶液、18.86g硝酸镥的水溶液和1870.5g柠檬酸溶液混合，水浴搅拌得到湿凝胶，烘干、600℃分解。将分解后的粉末在氢气气氛下进行还原，一次还原 温度为600℃，二次还原温度为900℃，随炉冷却得到稀土氧化物掺杂钼粉；采用等静压压型工艺，压型压力为150MPa，保压15min；坯体在氢气气氛下烧结，烧结温度为1900℃，得到稀土氧化物掺杂钼阴极棒材。随后进行旋煅、拉拔、清洗、矫直、绕制、定型、裁断工艺处理，得到未碳化的La2O3、Lu2O3掺杂Mo阴极。将未碳化的La2O3、Lu2O3掺杂Mo阴极进行装配磁控管工艺处理，组装后进行碳化处理，碳化温度为1600℃，保温80s，得到碳化度为28.2％的碳化La2O3、Lu2O3掺杂Mo阴极。将得到的碳化La2O3、Lu2O3掺杂Mo阴极进行装配后，得到未排气处理的电子管，对该电子管进行排气工艺处理，阴极排气温度为1800℃，保温30min。对排气处理后的电子管进行激活老化工艺处理，激活温度为1600℃，保温30min。测试电子管的直流发射特性，列于表1中。将激活老化处理后的电子管组装成磁控管。阴极的工作温度为1250℃。随后对微波炉的输出功率进行测试。
实施例6制备稀土氧化物添加量为4.5wt％的阴极，其余为钼。将1757.4g四水合七钼酸铵的水溶液、95.69g硝酸镧的水溶液、21.21g硝酸镥的水溶液和1874.3g柠檬酸溶液混合，水浴搅拌得到湿凝胶，烘干、650℃分解。将分解后的粉末在氢气气氛下进行还原，一次还原温度为600℃，二次还原温度为980℃，随炉冷却得到稀土氧化物掺杂钼粉；采用等静压压型工艺，压型压力为150MPa，保压15min；坯体在氢气气氛下烧结，烧结温度为1950℃，得到稀土氧化物掺杂钼阴极棒材。随后进行旋煅、拉拔、清洗、矫直、绕制、定型、裁断工艺处理，得到未碳化的La2O3、Lu2O3掺杂Mo阴极。将未碳化的La2O3、Lu2O3掺杂Mo阴极进行装配磁控管工艺处理，组装后进行碳化处理，碳化温度为1600℃，保温80s，得到碳化度为27.3％的碳化La2O3、Lu2O3掺杂Mo阴极。将得到的碳化La2O3、Lu2O3掺杂Mo阴极进行装配后，得到未排气处理的电子管，对该电子管进行排气工艺处理，阴极排气温度为1800℃，保温30min。对排气处理后的电子管进行激活老化工艺处理，激活温度为1600℃，保温30min。测试电子管的直流发射特性，列于表1中。将激活老化处理后的电子管组装成磁控管。阴极的工作温度为1250℃。随后对微波炉的输出功率进行测试。
实施例7制备稀土氧化物添加量为5wt％的阴极，其余为钼。将1748.2g四水合七钼酸铵的水溶液、106.32g硝酸镧的水溶液、23.58g硝酸镥的水溶液和1878.1g柠檬酸溶液混合，水浴搅拌得到湿凝胶，烘干、680℃分解。将分解后的粉末在氢气气氛下进行还原，一次还原温度为650℃，二次还原温度为850℃，随炉冷却得到稀土氧化物掺杂钼粉；采用等静压压型工艺，压型压力为150MPa，保压15min；坯体在氢气气氛下烧结，烧结温度为2000℃，得到稀土氧化物掺杂钼阴极棒材。随后进行旋煅、拉拔、清洗、矫直、绕制、定型、裁断工 艺处理，得到未碳化的La2O3、Lu2O3掺杂Mo阴极。将未碳化的La2O3、Lu2O3掺杂Mo阴极进行装配磁控管工艺处理，组装后进行碳化处理，碳化温度为1550℃，保温100s，得到碳化度为25.4％的碳化La2O3、Lu2O3掺杂Mo阴极。将得到的碳化La2O3、Lu2O3掺杂Mo阴极进行装配后，得到未排气处理的电子管，对该电子管进行排气工艺处理，阴极排气温度为1800℃，保温30min。对排气处理后的电子管进行激活老化工艺处理，激活温度为1600℃，保温30min。测试电子管的直流发射特性，列于表1中。将激活老化处理后的电子管组装成磁控管。阴极的工作温度为1250℃。随后对微波炉的输出功率进行测试。
表1各实施例得到的电子管的直流发射特性
Figure PCTCN2016113406-appb-000001

Claims (8)

  1. 碳化La2O3与Lu2O3复合掺杂Mo阴极材料，其特征在于，钼基体中掺杂稀土活性物质La2O3、Lu2O3，稀土活性物质添加量为阴极材料总量的2.0-5.0wt％，其余为钼；其中，La2O3与Lu2O3以任意比例混合。
  2. 按照权利要求1所述的碳化La2O3与Lu2O3复合掺杂Mo阴极材料，其特征在于，稀土活性物质添加量为阴极材料总量的3-4.5wt％。
  3. 按照权利要求1所述的碳化La2O3与Lu2O3复合掺杂Mo阴极材料，其特征在于，La2O3与Lu2O3的质量比为：(2-5)：1。
  4. 按照权利要求1所述的碳化La2O3与Lu2O3复合掺杂Mo阴极材料，其特征在于，La2O3与Lu2O3的质量比为4:1。
  5. 制备权利要求1所述的碳化La2O3与Lu2O3复合掺杂Mo阴极材料的方法，其特征在于，包括以下步骤：
    (1)将七钼酸铵溶液、硝酸镧溶液、硝酸镥溶液和柠檬酸溶液混合，其中七钼酸铵、硝酸镧、硝酸镥按照阴极材料中钼、氧化镧和氧化镥的质量比例添加，七钼酸铵：柠檬酸的质量比为1:(0.8-1.5)，水浴加热，机械搅拌。待溶液形成凝胶后取出，烘干，分解形成氧化物混合粉末；干凝胶分解温度为500-680℃；
    (2)将步骤(1)中获得氧化物混合粉末在氢气气氛中进行二次还原处理得到La2O3、Lu2O3掺杂Mo粉末，一次还原温度为500-680℃，二次还原温度为800-980℃；
    (3)将La2O3、Lu2O3掺杂Mo粉末进行压型、烧结处理，得到La2O3、Lu2O3掺杂Mo棒，烧结温度为1800-2030℃；
    (4)将步骤(3)中的La2O3、Lu2O3掺杂Mo棒进行旋煅、拉拔、清洗、矫直、绕制、定型、裁断工艺处理，得到未碳化的La2O3、Lu2O3掺杂Mo阴极；
    (5)将步骤(4)中的未碳化的La2O3、Lu2O3掺杂Mo阴极进行装配磁控管工艺处理，组装后进行碳化处理，碳化温度为1550-1900℃，保温60-150s，得到碳化度为10-50％的碳化La2O3、Lu2O3掺杂Mo阴极。
  6. 按照权利要求5的方法，其特征在于，进一步制备成磁控管，包括以下步骤：将得到的碳化La2O3、Lu2O3掺杂Mo阴极进行装配后，进行排气工艺处理，阴极排气电流为10-12.5A，排气温度为1600-1900℃，保温20-60min；对排气处理后的电子管进行激活老化工艺处理，激活温度为1450-1650℃，保温10-30min；将激活老化处理后的电子管组装成磁控管。
  7. 权利要求1-6任一项所述的碳化La2O3与Lu2O3复合掺杂Mo阴极材料的应用，其特征在于，工作温度为1200-1400℃。
  8. 权利要求1-6任一项所述的碳化La2O3与Lu2O3复合掺杂Mo阴极材料的应用，其特征在于，碳化La2O3与Lu2O3复合掺杂Mo阴极材料用于微波炉中使用的磁控管。
PCT/CN2016/113406 2016-08-26 2016-12-30 碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法 WO2018036068A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US15/757,343 US10388484B2 (en) 2016-08-26 2016-12-30 Carburized La2O3 and Lu2O3 co-doped Mo filament cathode

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201610743795.4 2016-08-26
CN201610743795.4A CN106206216B (zh) 2016-08-26 2016-08-26 碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法

Publications (1)

Publication Number Publication Date
WO2018036068A1 true WO2018036068A1 (zh) 2018-03-01

Family

ID=57526240

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2016/113406 WO2018036068A1 (zh) 2016-08-26 2016-12-30 碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法

Country Status (3)

Country Link
US (1) US10388484B2 (zh)
CN (1) CN106206216B (zh)
WO (1) WO2018036068A1 (zh)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106206216B (zh) * 2016-08-26 2018-04-17 北京工业大学 碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6281626B1 (en) * 1998-03-24 2001-08-28 Casio Computer Co., Ltd. Cold emission electrode method of manufacturing the same and display device using the same
CN101447376A (zh) * 2008-12-31 2009-06-03 北京工业大学 Y2O3-Lu2O3体系复合稀土-钼电子发射材料及其制备方法
CN103700557A (zh) * 2013-12-24 2014-04-02 北京工业大学 一种碳化稀土氧化镥掺杂钼阴极材料及其制备方法
CN103849804A (zh) * 2014-03-01 2014-06-11 深圳市威勒达科技开发有限公司 一种微波炉磁控管用无辐射多元复合钨阴极材料及其制备工艺
CN106206216A (zh) * 2016-08-26 2016-12-07 北京工业大学 碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0798758A1 (fr) * 1996-03-28 1997-10-01 THOMSON TUBES & DISPLAYS S.A. Procédé de fabrication d'une cathode imprégnée pour tube à rayons cathodiques
KR100297687B1 (ko) * 1998-09-24 2001-08-07 김순택 전자총용음극
CN1089813C (zh) * 1999-07-12 2002-08-28 北京工业大学 电子管阴极材料及其制备方法
CN1131330C (zh) * 2001-11-22 2003-12-17 北京工业大学 二元稀土钼次级发射材料及其制备方法
CN1178259C (zh) * 2002-07-24 2004-12-01 北京工业大学 三元稀土钼次级发射材料及其制备方法
RU2342732C1 (ru) * 2007-10-24 2008-12-27 Федеральное государственное унитарное предприятие "Научно-производственное предприятие "Торий" Металлопористый пропитанный катод для магнетрона

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6281626B1 (en) * 1998-03-24 2001-08-28 Casio Computer Co., Ltd. Cold emission electrode method of manufacturing the same and display device using the same
CN101447376A (zh) * 2008-12-31 2009-06-03 北京工业大学 Y2O3-Lu2O3体系复合稀土-钼电子发射材料及其制备方法
CN103700557A (zh) * 2013-12-24 2014-04-02 北京工业大学 一种碳化稀土氧化镥掺杂钼阴极材料及其制备方法
CN103849804A (zh) * 2014-03-01 2014-06-11 深圳市威勒达科技开发有限公司 一种微波炉磁控管用无辐射多元复合钨阴极材料及其制备工艺
CN106206216A (zh) * 2016-08-26 2016-12-07 北京工业大学 碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法

Also Published As

Publication number Publication date
US20180254164A1 (en) 2018-09-06
US10388484B2 (en) 2019-08-20
CN106206216A (zh) 2016-12-07
CN106206216B (zh) 2018-04-17

Similar Documents

Publication Publication Date Title
CN110303165B (zh) 一种浸渍型氧化钪掺杂铼钨多相混合基扩散阴极及制备方法
US10651000B2 (en) Method for preparing pressed scandia-doped dispenser cathodes using microwave sintering
CN111099907B (zh) 一种表面改性氧化锆纤维复合稀土锆酸镧的高性能陶瓷及其制备方法
CN111041314B (zh) 一种高强度钼合金杆及其制备方法
WO2018036068A1 (zh) 碳化La2O3与Lu2O3复合掺杂Mo阴极材料及其制备方法
CN105304436B (zh) 直热式阴极及其制备方法
CN105702542A (zh) 铼掺杂钨基合金阴极及其制备方法
CN105645946B (zh) 一种浸渍扩散阴极用含钪铝酸盐及其制备方法
CN108878234B (zh) 一种ZrH2添加的Y2O3-W基次级发射体的制备方法
CN101625950B (zh) 含钇的压制型钡钨阴极及其制备方法
JP4648527B2 (ja) カソードの製造方法
CN109065422B (zh) 一种直热式高温钨铼合金阴极的制备方法
CN103700557B (zh) 一种碳化稀土氧化镥掺杂钼阴极材料及其制备方法
CN106328468B (zh) 磁控管用La2O3掺杂Mo阴极材料的制备方法
CN1089813C (zh) 电子管阴极材料及其制备方法
Wang et al. Recent progress of cathodes in high-power continuous wave magnetron tubes
CN110358509A (zh) 一种提高ods-w复合材料导热性能的方法
CN101628336B (zh) 一种含钪扩散阴极材料的制备方法
CN1078260C (zh) 复合稀土钼材料及其制备方法
CN107382321A (zh) 一种超细碳化锆粉体及其制备方法
CN108218425B (zh) 一种Sb掺杂的立方相Ca2Ge基热电材料及其制备方法
CN101447377B (zh) Y2O3-Gd2O3体系复合稀土-钼电子发射材料及其制备方法
CN101640155A (zh) 铼钨多元素发射灯丝及用途
CN110615474A (zh) 一种热阴极用铪酸盐电子发射活性物质的制备方法
CN115346727A (zh) 一种高温热阴极的制备方法

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 15757343

Country of ref document: US

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16914088

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC (EPO FORM 1205A DATED 24/07/2019)

122 Ep: pct application non-entry in european phase

Ref document number: 16914088

Country of ref document: EP

Kind code of ref document: A1