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CN-122025489-A - Electrode for discharge tube and preparation method and application thereof

CN122025489ACN 122025489 ACN122025489 ACN 122025489ACN-122025489-A

Abstract

The invention belongs to the technical field of discharge tubes, and particularly relates to an electrode for a discharge tube, a preparation method and application thereof. The electrode comprises i) a tungsten copper electrode, ii) a metal substrate layer formed on the surface of the i) and comprising a copper metal layer and a silver-copper-titanium composite metal layer which are sequentially formed on the surface of the tungsten copper electrode from inside to outside, iii) an electron emission material intermediate layer formed on the surface of the ii), and iv) a nickel sponge outermost layer formed on the surface of the iii). The electrode provided by the invention can obviously reduce the loss and sputtering of the electron emission material when the discharge tube is in impulse conduction under the condition of ensuring the basic performance of the electron emission material, obviously prolong the impulse conduction service life of the discharge tube and effectively prevent the insulation resistance of the discharge tube from being reduced.

Inventors

  • HAN CONGYING
  • BAI YINGJIE
  • XIN TONGZE
  • SU ZHIGUO
  • ZHANG MINGZHI
  • Meng Tianxu

Assignees

  • 北京全路通信信号研究设计院集团有限公司

Dates

Publication Date
20260512
Application Date
20260104

Claims (10)

  1. 1. An electrode for a discharge vessel, the electrode comprising: i) A tungsten copper electrode; ii) a metal basal layer formed on the surface of the i), comprising a copper metal layer and a silver-copper-titanium composite metal layer which are sequentially formed on the surface of the tungsten copper electrode from inside to outside; iii) An electron emission material intermediate layer formed on the surface of ii), and, Iv) an outermost layer of nickel sponge formed on the surface of iii).
  2. 2. The electrode of claim 1, wherein the metal base layer has a thickness of 0.1 to 0.2mm; and/or the thickness of the copper metal layer is 2-8 mu m; and/or the thickness of the electron emission material intermediate layer is 0.8-1 mm; and/or the thickness of the outermost layer of the nickel sponge is 0.1-0.2 mm.
  3. 3. The electrode according to claim 1, wherein the electron-emitting material comprises an alkali oxide and a silicate, and/or wherein the electron-emitting material has a D50 particle diameter of 0.2 to 0.5 μm and a particle relative density of >92%.
  4. 4. The electrode of claim 1, wherein the nickel sponge has a porosity of 25-35%.
  5. 5. A method of producing an electrode according to any one of claims 1 to 4, comprising: providing a tungsten copper electrode; Depositing metallic copper on the surface of the tungsten copper electrode in an electroplating mode; coating slurry containing silver copper welding powder and titanium powder on the surface of an electrode on which metal copper is deposited, and carrying out vacuum sintering; coating slurry containing carbonate and silicate on the surface of the electrode after vacuum sintering, then uniformly spraying nickel powder, and vacuum sintering again.
  6. 6. The preparation method according to claim 5, wherein the particle size of the silver copper solder powder is 1-10 μm; and/or the D50 particle size of the titanium powder is 10-25 mu m; And/or the particle size of the carbonate is 1-10 mu m; and/or the particle size of the silicate is 1-10 mu m; and/or the particle size of the nickel powder is 1-10 mu m.
  7. 7. The preparation method of claim 5, wherein the mass ratio of the silver copper welding powder to the titanium powder is 0.5-1.5:0.5-1.5; And/or the mass ratio of silver to copper of the silver copper welding powder is 1:1; And/or the mass ratio of the carbonate to the silicate is 63-67:22-25.
  8. 8. The method of claim 5, wherein the carbonate is a divalent carbonate and the silicate is a monovalent silicate.
  9. 9. The method according to claim 5, wherein the temperatures of the two vacuum sintering steps are 650-900 ℃ and 1400+ -20 ℃.
  10. 10. A discharge vessel comprising two oppositely arranged electrodes and two oppositely arranged ceramic tubes enclosing a closed space with an inner cavity, characterized in that the electrodes are as claimed in any one of claims 1-4.

Description

Electrode for discharge tube and preparation method and application thereof Technical Field The invention belongs to the technical field of discharge tubes, and particularly relates to an electrode for a discharge tube, a preparation method and application thereof. Background The discharge tube component comprises an upper electrode, a lower electrode, a ceramic tube, an electron emission material, a carbon wire and the like, wherein the upper electrode and the lower electrode are used for electrically connecting the discharge tube with a circuit and conducting current, a physical gap exists between the upper electrode and the lower electrode, the electron emission material is coated on the discharge surface of the electrode, and the electron emission material is a key material for conducting the discharge tube. When the discharge tube is not in operation, the upper and lower electrodes of the discharge tube are connected between the wires or the ground of the circuit, and a voltage is applied between the electrodes. The discharge vessel does not operate because the voltage is lower than the turn-on voltage of the discharge vessel. When the upper electrode and the lower electrode of the discharge tube receive the impulse voltage U, the voltage is higher than the conduction voltage of the discharge tube, so that the physical gap between the upper electrode and the lower electrode of the discharge tube is broken down to form a current channel, and the current is discharged from the discharge tube, thereby protecting the protected circuit. The electron emission material is coated on the surface of the electrode, various characteristic substances exist in the electron emission material, mainly charged particles with low work function are provided, when the voltage U is impacted between the electrodes, the charged particles with low work function are started to reach the opposite electrode first, an initial channel is established, and the physical gap between the electrodes is finally broken down along with the increasing of the moving quantity of the charged particles, so that a conductive channel is formed. Therefore, the electron emission material is a main material for establishing a conducting channel of the discharge tube, if the electron emission material is not present, the conducting voltage of the discharge tube may rise by 10 times as much as U, and the conducting voltage is unstable, so that the protected circuit cannot be protected. However, since the electron emission material is excited to create a conductive channel for the discharge tube, the electron emission material on the surface of the electrode is greatly reduced after the continuous high-frequency impact conduction, and is sputtered to each corner inside the discharge tube, so that various hazards are caused, namely, 1, the electron emission material on the electrode is reduced, the breakdown voltage of the discharge tube is unstable and even increases, the protection effect is affected, until the electron emission material is completely sputtered, 2, the sputtered electron emission material is accumulated on the wall of the opposite electrode or the ceramic tube, and the electron emission material is a conductive material, so that the environment in the cavity is changed, the insulation resistance between the upper electrode and the lower electrode is reduced, and even short circuit is caused. Disclosure of Invention The invention provides an electrode for a discharge tube, a preparation method and application thereof, aiming at the problems of the prior discharge tube electron emission material. The electrode provided by the invention can obviously reduce the loss and sputtering of the electron emission material when the discharge tube is in impulse conduction under the condition of ensuring the basic performance of the electron emission material, obviously prolong the impulse conduction service life of the discharge tube and effectively prevent the insulation resistance of the discharge tube from being reduced. In a first aspect, the invention provides an electrode for a discharge tube, comprising i) a tungsten copper electrode, ii) a metal base layer formed on the surface of i), comprising a copper metal layer and a silver-copper-titanium composite metal layer formed on the surface of the tungsten copper electrode in sequence from the inside to the outside, iii) an electron emission material intermediate layer formed on the surface of ii), and iv) a nickel sponge outermost layer formed on the surface of iii). Because the tungsten-copper electrode is a pseudo alloy, tungsten and copper are not completely melted, in order to improve the melting property of the tungsten-copper electrode and the electron emission material, a copper metal layer is firstly formed on the surface of the tungsten-copper electrode, so that the conductivity is enhanced, the tungsten-copper electrode is easier to be melted and combined with the electron emission