CN205751547U - A kind of small-sized Penning ion source device for compact neutron generator - Google Patents

Abstract

The utility model discloses a small-sized Penning ion source device for a compact neutron generator, which comprises a cathode (1), an anode (2), a permanent magnet (3), a storage device (4), and a magnetically conductive material ( 5), lead-out hole (6). The two cathodes adopt an integrated design and are formed by spinning a kovar plate; the anode is made of non-magnetic stainless steel material in the shape of a cylinder; the magnetic material is made of soft iron with a thickness of about 3mm; the storage is used to adjust the gas in the ion source pressure situation. The Penning ion source device has a small size and a discharge current of about 300μA-600μA, which can be conveniently used in a compact neutron generator and better meet the requirements of the compact neutron generator.

Description

A small Penning ion source setup for a compact neutron generator

technical field

The utility model belongs to a Penning ion source device, in particular to a small Penning ion source device used in a compact neutron generator.

Background technique

Compact neutron generators are widely used in various industrial applications due to their small size, convenient control, and safe use, such as drug and explosive detection, neutron logging, and coal quality analysis. As the core component of the neutron generator, the working characteristics of the ion source have a decisive impact on the product performance of the neutron generator, such as neutron yield and life.

Penning ion source is a typical type of ion source widely used in neutron generators. It can work under low pressure conditions, has the characteristics of simple structure and power supply system, and long working life. The current requirement for the miniaturization of compact neutron generators requires reducing the size of Penning ion sources as much as possible, so it is of great practical significance to develop small Penning ion source devices for compact neutron generators.

Contents of the invention

The purpose of the utility model is to provide a small Penning ion source device that can be applied to a compact neutron generator, including a cathode, an anode, a permanent magnet, a storage, a magnetic material, and an extraction hole. Two of the cathodes adopt an integrated design and are formed by spinning a kovar plate; the anode is made of non-magnetic stainless steel, and the shape is a cylinder with a diameter of 17mm and a height of 9mm; the storage is connected with the cathode to adjust the vacuum degree in the ion source The magnetically permeable material is placed on the inner side of the cathode and placed opposite to the anode. The magnetically permeable material is selected from soft iron with the same diameter as the anode and a thickness of 3mm;

The beneficial effects of the utility model are: (1) the size is small, the length is about 35mm, and the width is about 30mm, which can meet the requirements of a compact neutron generator. (2) The discharge current characteristic is good. The discharge current range of the Penning ion source is 300μA-600μA, and the neutron yield can reach 2×10 ⁸ n/s, which can meet the requirements of general industrial applications.

Description of drawings

Fig. 1 is the structural representation of the utility model.

detailed description

Referring to FIG. 1 , a small Penning ion source device that can be applied to a compact neutron generator includes a cathode 1 , an anode 2 , a permanent magnet 3 , a storage 4 , a magnetically permeable material 5 , and an extraction hole 6 . There are two cathodes 1, which adopt an integrated design and are formed by spinning a kovar plate; the anode 2 is a cylinder made of non-magnetic stainless steel, with a diameter of 17mm and a height of 8mm; the distance between the anode 2 and the cathode 1 Up, down, left, and right are about 2mm; the magnetically permeable material 5 is located on the inner side of the kovar plate that constitutes the cathode, and is placed opposite to the anode 2, where the soft iron with the same diameter as the anode 2 and a thickness of 3mm is used; the storage 4 is connected to the cathode 1, It is used to adjust the vacuum degree in the ion source; the extraction hole 6 is opened on the cathode 1 and the magnetic permeable material 5 away from the permanent magnet, with a diameter of 3mm. The size of the entire Penning ion source is about 35mm in length and 30mm in width, which can be better used in a compact neutron generator.

In a Penning ion source, the motion of electrons is constrained in two ways. One is the limitation of the axial movement of electrons by the external electric field. When the electrons move axially to the vicinity of the two ends, the strong repulsion force of the cathode prevents them from escaping the section along the axial direction; Restriction of directional movement, electrons move in a circle around the magnetic force lines under the action of a uniform magnetic field, which limits the movement of electrons to the anode 2 . Under the simultaneous restriction of these two aspects, electrons will move back and forth spirally in space for a long time. As long as the number of electrons entering the anode 2 per unit time is equal to the number of new electrons generated by ionization, a dynamic equilibrium state will be reached, and a stable self-sustaining discharge will appear in the ion source. The discharge current range of the Penning ion source is about 300μA-600μA, and when used in a compact neutron generator, the neutron yield can reach 2×10 ⁸ n/s.

Claims (5)

1. the small-sized Penning ion source device for compact neutron generator, it is characterised in that: include negative electrode (1), sun Pole (2), permanent magnet (3), bin (4), permeability magnetic material (5), fairlead (6), its Anodic is placed in the center of negative electrode, forever Magnet is connected with cathode outer side, and bin is connected with cathode outer side, and permeability magnetic material is connected with inside negative electrode, and and anode Staggered relatively, fairlead is opened on the negative electrode away from permanent magnet and permeability magnetic material.

A kind of small-sized Penning ion source device for compact neutron generator the most according to claim 1, its feature It is: described negative electrode uses integrated design, can be cut down plate spinning by one piece and form.

A kind of small-sized Penning ion source device for compact neutron generator the most according to claim 1, its feature It is: described anode selects non-magnetic rustproof Steel material, is shaped as the cylinder of diameter 17mm height 9mm.

A kind of small-sized Penning ion source device for compact neutron generator the most according to claim 1, its feature Being: described permeability magnetic material is placed in inside negative electrode, staggered relatively with anode, it selects thickness to be the soft iron of 3mm.

A kind of small-sized Penning ion source device for compact neutron generator the most according to claim 1, its feature It is: described fairlead is opened on the negative electrode away from permanent magnet and permeability magnetic material, a diameter of 3mm.