RU2641641C2 - Method of perforating holes in electrodes of ion optical system - Google Patents

Abstract

FIELD: physics.SUBSTANCE: in a method for perforating holes in the electrodes of ion-optical system, based on the formation of ion beams and their subsequent impact onto the surface of the electrode, ion-optical system including an emission electrode is collected before exposing the ion beams onto the surface, then a discharge is formed, creating a flow of ions and directing it through the holes of the emission electrode on the processed surface of the electrode, where the ions are sprayed to the electrode material at the points of exposure.EFFECT: simplification of alignment between the holes in the electrodes when assembling the ion-optical system.4 dwg

Description

The present invention relates to the field of plasma technology, namely to ion systems, and can be used in the field of rocket and space technology, in the development, manufacture and assembly of an ion-optical system (IOS) of ion engines (ID), ion guns and accelerators.

IOS is constructively and technologically the most complex and critical element of ID. It consists, as a rule, of emission, accelerating and slowing-down electrodes in which holes are made, and usually the holes in each of the electrodes have their own diameter, different from the holes in other electrodes. One of the most important problems in the manufacture and assembly of IOS ID is the accuracy of the manufacture of IOS electrodes, ensuring both the gap between the electrodes and the alignment of the holes in the electrodes.

Changing the gap between the electrodes by 10% compared with the calculated nominal value leads to a drop in current density to 5%, a deviation of the diameter of the holes in the electrodes from the nominal by 2.5% leads to a decrease in current density by 2-6.5%, deviation of the pine between holes by 2.5% leads to a drop in current density to 5%. In addition, a poorly focused ion beam leads to sputtering of the walls of the holes in the electrodes, which ultimately leads to a deterioration in the parameters of the ID. All this requires special attention, creates significant difficulties in the design, manufacture and assembly of IOS ID.

A known method of perforation of the holes of the ion-optical system containing emission, accelerating and slowing electrodes. The method includes layering carbon fibers or carbon fiber fabric on the working surface of the forming element (RF patent No. 2543063 (2013) "Method for the manufacture of electrodes of the ion-optical system" - analogue; L. Lesnevsky. Production technology of space engines and power plants using nanomaterials : Educational-methodical complex / LN Lesnevsky, VN Tyurin. - Kaluga, Moscow: Eidos Publishing House, 2011. - 482 p .; - prototype).

This method of perforation of the ion-optical system has the following disadvantages:

- the difficulty of ensuring alignment between the holes in the electrodes during assembly;

- the difficulty of ensuring alignment between the holes in the electrodes associated with the consideration of thermal displacement;

- the difficulty of ensuring alignment between the holes in the electrodes associated with the convexity (warping) of the electrodes themselves;

- high requirements for precision manufacturing of electrodes;

- limited parameters of the geometric shapes of the holes.

The aim of the invention is to remedy these disadvantages, namely:

- simplification of ensuring alignment between the holes in the electrodes when assembling the IOS;

- simplification of ensuring alignment between the holes in the electrodes, taking into account thermal displacement;

- simplification of ensuring alignment between the holes associated with the convexity (warping) of the electrodes themselves;

- reducing the requirements for precision manufacturing of electrodes;

- expanding the parameters of the geometric shapes of the holes in the electrodes.

In the present invention, the technical effect is achieved by the fact that in the known method of perforating holes in the electrodes of the ion-optical system, based on the formation of ion beams with their subsequent action on the treated electrode surface, according to the invention, an ion-optical system is assembled before the ion beams on the treated surface, including the emission electrode, then form a discharge, creating a stream of ions, and direct it through the holes of the emission electrode on the surface awn electrode where the ions of the electrode material is sprayed in the target points.

The indicated set of features exhibits new properties, which make it possible to ensure high accuracy in the manufacture of the perforated lattice of the electrodes of the ion-optical system, minimizing the time for its manufacture and subsequent adjustment (adjustment) of the alignment of the holes between the electrodes during assembly.

The proposed “technology” of perforation of the electrodes of the ion-optical system is illustrated in FIG. 1 (general diagram), in FIG. 2, 3 presents an element of the ion-optical system, where:

1 - emission electrode;

2 - accelerating electrode;

3 - retarding electrode;

4 - inner flange of the emission electrode;

5 - outer flange of the emission electrode;

6 - holes in the emission electrode;

7, 14 - an adjusting washer;

8, 9, 12, 13 - ceramic insulator;

10, 11 - screw;

15 - ion beam;

16 - holes in the accelerating electrode;

I _UE is the current strength of the accelerating electrode;

I _EE - current strength of the emission electrode.

The ion-optical system consists of an emission electrode 1 with holes 5 forming an aperture mesh, and an accelerating 2 electrodes, flanges 3, 4 of the emission electrode, ceramic insulators 6, 8, shims 7. An insulator between the electrodes to prevent breakdowns due to atomization of the material accelerating electrode can be covered with a metal mesh.

The principle of manufacturing the holes of the accelerating electrode for the ion-optical system is as follows.

The ion-optical system (IOS), complete with a gas discharge chamber (GRC), is placed in a vacuum chamber. In the GRK, a plasma discharge is ignited. The finished perforated EE 1 and the processed UE 2 is fed the voltage difference. The emerging ion beams bombard the UE 2, starting to spray the material (Fig. 2).

Due to the prolonged exposure to ion beams on the UE 2, holes will begin to form (Fig. 3). This method improves the alignment accuracy of the holes even taking into account thermal displacement. Moreover, the quality and shape of the holes in the electrodes of the EE does not matter.

To clarify the readiness of the RE holes, the current strengths of the I _RE and the I _E are taken from the electrodes. At the beginning of the manufacture of holes, I _UE = I _EE , since the entire ion charge settles on the UE. During the operation, ion beams will begin to penetrate and pass through the holes formed (Fig. 2). As a result of this, the current strength of the UE I _UE will begin to fall (Fig 3.). UE openings are considered to be finally finished when I _UE <0.1⋅I _EE (Fig. 4).

The manufacture of perforated mesh with this method will increase the high accuracy of alignment between the holes of the electrodes during assembly. And since perforation of REs requires only one ready-made EE, this reduces the requirements for the accuracy of manufacturing EE itself, which reduces the cost of the cost of manufacturing the electrodes.

Thus, through the use of the invention, the manufacture of the holes of the electrodes of the ion-optical system is ensured with a minimum deviation of the alignment of the holes between the electrodes from the nominal design value, which will ensure a minimum variation in the parameters and characteristics of the ion-optical system for any geometric shapes of the electrodes.

Claims (1)

A method of perforating holes in the electrodes of an ion-optical system, based on the formation of ion beams with their subsequent exposure to the treated electrode surface, characterized in that before the action of ion beams on the treated surface, an ion-optical system is assembled, including an emission electrode, then a discharge is formed, creating ion flow, and direct it through the holes of the emission electrode to the electrode surface to be treated, where ions spray the electrode material at the points of influence.

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