High yield deuterium tritium neutron tube

Abstract

The utility model relates to a neutron tube, concretely relates to a high-yield deuterium tritium neutron tube. The neutron tube includes ion source kovar ring, connecting pipe, target kovar ring, ion source subassembly, accelerating electrode, target subassembly and heat radiation structure, ion source kovar ring, connecting pipe and target kovar ring are coaxial connection in proper order, ion source subassembly is installed in ion source kovar ring through the heat radiation ring, and its outer end is used for connecting external power supply and external deuterium source, and the inner end extends to the inner chamber of connecting pipe along the axial direction, target subassembly is installed in target kovar ring, and one end of accelerating electrode is installed in the inner end of target subassembly, and the other end is provided with accelerating gap between the inner end of ion source subassembly, and heat radiation structure is installed at the outer end of target subassembly. The utility model sets up target subassembly forced heat radiation structure structure, and the temperature rise of target subassembly when working is forcedly reduced.

Description

Technical Field

[0001] This utility model relates to a neutron tube, specifically a high-yield deuterium-tritium neutron tube. Background Technology

[0002] With the development of controlled neutron source technology, the demand for technologies such as non-destructive neutron detection, neutron radiography, and neutron-based cancer diagnosis and treatment is increasing. The core component for these technologies is the high-yield deuterium-tritium neutron tube, which typically requires a neutron yield of 1 × 10⁻⁶. 10 n / s or more.

[0003] Currently, the neutron yield of deuterium-tritium neutron tubes is concentrated in the 10-1 range. 8 The n / s level can approach 10 under extreme operating conditions. 10 It operates at the n / s level, but cannot work continuously and stably, thus failing to meet the application technology requirements mentioned above. Utility Model Content

[0004] The purpose of this invention is to solve the technical problem that the neutron yield of existing deuterium-tritium neutron tubes is low and difficult to meet actual needs, and to provide a high-yield deuterium-tritium neutron tube.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] A high-yield deuterium-tritium neutron tube, which is special in that:

[0007] It includes an ion source Kovar ring, a connecting tube, a target Kovar ring, an ion source assembly, an accelerating electrode, a target assembly, and a heat dissipation structure;

[0008] The ion source Kovar ring, the connecting tube, and the target Kovar ring are coaxially connected in sequence.

[0009] The ion source assembly is installed inside the Kovar ring of the ion source via a heat dissipation ring. Its outer end is used to connect to an external power source, and its inner end extends axially into the inner cavity of the connecting tube. The ion source assembly is used to ionize deuterium gas into deuterium ions under ionization and then output them from its inner end.

[0010] The target assembly is installed inside the Kovar ring of the target. One end of the accelerating electrode is installed at the inner end of the target assembly, and an accelerating gap is provided between the other end of the electrode and the inner end of the ion source assembly. The accelerating electrode is used to accelerate deuterium ions and output them to the target surface of the target assembly. The target assembly is used to generate high-energy neutron emission under the deuterium-tritium nucleus reaction.

[0011] The heat dissipation structure is installed at the outer end of the target assembly and is used to connect to an external heat dissipation system to dissipate heat from the target assembly.

[0012] Furthermore, the outer peripheral surface of the ion source Kovar ring is provided with a plurality of heat dissipation ring grooves distributed along the axial direction.

[0013] Furthermore, the heat dissipation ring groove is a rectangular ring groove.

[0014] Furthermore, the target assembly includes a front magnetic ring and a target substrate;

[0015] The inner diameter of the target Kovar ring is larger than the inner diameter of the connecting pipe;

[0016] The outer diameter of the front magnet ring is adapted to the inner diameter of the Kovar ring of the target. The front magnet ring is installed inside the Kovar ring of the target, and one end of it abuts against the outer end of the connecting tube.

[0017] The outer peripheral surface of the target substrate is provided with a first annular protrusion. The outer diameter of the first annular protrusion is adapted to the inner diameter of the Kovar ring of the target. The target substrate is installed inside the Kovar ring of the target through the first annular protrusion and is located at the other end of the front magnet ring. A radial mounting gap is provided between the outer peripheral surface of the inner end of the target substrate and the inner peripheral surface of the front magnet ring. One end of the accelerating electrode passes through the mounting gap and is installed on the outer peripheral surface of the inner end of the target substrate, while its outer peripheral surface abuts against the inner peripheral surface of the front magnet ring.

[0018] The inner end face of the target substrate is the target surface;

[0019] The outer end face of the target substrate is provided with a mounting groove, and the heat dissipation structure is installed in the mounting groove.

[0020] Furthermore, the heat dissipation structure is an oil circulation heat dissipation structure;

[0021] The input end of the oil circulation cooling structure is connected to the output end of an external oil pump, and the output end is connected to the input end of the oil pump via a radiator.

[0022] Furthermore, an oil passage gap is provided between the inner end of the oil circulation heat dissipation structure and the bottom of the mounting groove. The outer end of the heat dissipation structure is provided with two oil passage holes along the axial direction, both of which are connected to the oil passage gap. One oil passage hole is connected to the output end of an external oil pump, and the other oil passage hole is connected to the input end of the oil pump via a radiator.

[0023] Furthermore, a second annular protrusion is provided on the outer peripheral surface of the heat dissipation structure, and the inner side of the second annular protrusion abuts against the outer end of the target substrate through a sealing ring.

[0024] Furthermore, the ion source Kovar ring, the connecting tube, and the target Kovar ring are sequentially welded by vacuum brazing;

[0025] The connecting pipe is an externally corrugated ceramic pipe.

[0026] Furthermore, the outer end of the ion source assembly is provided with three sealed and insulated terminals and a sealed oxygen-free copper tube;

[0027] Two of the sealed insulated terminals are used to connect to an external low-voltage power supply, and the third sealed insulated terminal is used to connect to an external anode high-voltage power supply.

[0028] The oxygen-free copper tube is used to connect to an external vacuum pumping device during vacuuming.

[0029] The beneficial effects of this utility model are:

[0030] 1. This utility model is equipped with an ion source heat dissipation structure: a heat dissipation ring and an ion source Kovar ring with rectangular grooves, which will effectively reduce the temperature rise of the ion source assembly when the neutron tube is working.

[0031] 2. This utility model uses an external corrugated ceramic tube structure: effectively increasing the insulation strength of the external ceramic surface of the neutron tube, while shortening the external dimensions of the neutron tube;

[0032] 3. This utility model is equipped with a front magnetic steel ring structure: it directly forms a magnetic field with a specific strength and shape on the target surface, which effectively produces a suppression effect on secondary electrons;

[0033] 4. This utility model is equipped with a target forced heat dissipation external circulation structure: by using an external circulation and heat exchange heat sink, the temperature rise of the target substrate is forcibly reduced when the neutron tube is working. Attached Figure Description

[0034] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model;

[0035] Figure 2 This is a schematic diagram of the connection structure between a high-yield deuterium-tritium neutron tube and an external oil pump and radiator according to this utility model.

[0036] In the diagram: 1-Ion source Kovar ring, 2-Heat dissipation ring, 3-Ion source assembly, 4-Connecting pipe, 5-Accelerating gap, 6-Accelerating electrode, 7-Target surface, 8-Target Kovar ring, 9-Target front magnetic steel ring, 10-Target substrate, 11-Oil circulation heat dissipation structure, 12-Sealing ring, 13-Magnetic lines of force, 14-Insulating oil pipeline, 15-Oil pump, 16-Radiator, 17-Sealed insulating terminal block, 18-Oxygen-free copper pipe, 19-Oil passage gap, 20-Oil passage hole, 21-Heat dissipation ring groove. Detailed Implementation

[0037] To make the objectives, advantages, and features of this utility model clearer, the high-yield deuterium-tritium neutron tube proposed by this utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of this utility model will become clearer according to the following specific embodiments.

[0038] It should be noted that in this embodiment, "left" and "right" are both based on... Figure 1 Use the paper orientation as a reference.

[0039] See Figure 1 This embodiment of a high-yield deuterium-tritium neutron tube mainly includes an ion source Kovar ring 1, a connecting tube 4, a target Kovar ring 8, an ion source assembly 3, an accelerating electrode 6, a target assembly, and a heat dissipation structure.

[0040] Among them, the Kovar ring 1 of the ion source, the connecting tube 4 and the Kovar ring 8 of the target are arranged coaxially from left to right and are welded in sequence by vacuum brazing to form a cylindrical sealed shell.

[0041] In this embodiment, the connecting tube 4 is an externally corrugated ceramic tube 4, specifically an A95 ceramic tube for electrovacuum applications. In other embodiments of this utility model, it may also be made of glass.

[0042] The ion source assembly 3 is a pre-fabricated integral structural component. Its function is to form deuterium ions of a specific density when the neutron tube is working. The right end of the ion source assembly 3 is provided with a 4.5mm opening, which serves as the output port to output the ionized deuterium ions.

[0043] A metal heat dissipation ring 2 is nested in the middle of the outer peripheral surface of the ion source assembly 3. The ion source assembly 3 is installed inside the ion source Kovar ring 1 through the heat dissipation ring 2, and the right end of the ion source assembly 3 extends axially into the inner cavity of the connecting pipe 4. Simultaneously, multiple axially distributed heat dissipation ring grooves 21 are provided on the outer peripheral surface of the ion source Kovar ring 1, thereby increasing the surface area of ​​the ion source Kovar ring 1 and enhancing the heat dissipation effect. Specifically, the heat dissipation ring grooves 21 can be rectangular, triangular, etc. Considering factors such as processing technology and heat dissipation area, a rectangular ring groove is preferred in this embodiment.

[0044] The left end of the ion source assembly 3 is equipped with three sealed insulated terminals 17 and a sealed oxygen-free copper tube 18. Two of the sealed insulated terminals 17 are used to connect to an external low-voltage power supply to generate deuterium gas inside the ion source. The third sealed insulated terminal 17 is used to connect to an external anode high-voltage power supply to form an ionization electric field in the internal working area of ​​the ion source assembly 3. The oxygen-free copper tube 18 is used to connect to an external vacuum pumping device during vacuuming.

[0045] Accelerating electrode 6 is installed on the left end of the target assembly. Accelerating electrode 6 has a hollow truncated cone structure with an 18mm aperture on its left end and a 4.5mm aperture on its right end. An accelerating gap 5 is provided between the left end of accelerating electrode 6 and the right end of ion source assembly 3. Accelerating electrode 6 is used to accelerate deuterium ions and output them to the target surface 7 of the target assembly.

[0046] The target assembly is used to generate high-energy neutron emission under deuterium-tritium nuclear reaction. The target assembly is installed inside the target Kovar ring 8. Specifically, the target assembly includes a front-mounted magnetic ring 9 and a target substrate 10; the magnetic field lines 13 generated by the front-mounted magnetic ring 9 are as follows: Figure 2 As shown. The left side of the target substrate 10 is treated with a special process and pre-deposited with a titanium metal film of a specific thickness in a vacuum environment to form the target surface 7; the inner diameter of the target Kovar ring 8 is larger than the inner diameter of the connecting tube 4; the outer diameter of the front magnet ring 9 is adapted to the inner diameter of the target Kovar ring 8, and the front magnet ring 9 is installed inside the target Kovar ring 8, with its left end abutting against the right end of the connecting tube 4; a first annular boss is provided on the outer peripheral surface of the target substrate 10, the outer diameter of which is adapted to the inner diameter of the target Kovar ring 8, and the target substrate 10 is installed inside the target Kovar ring 8 through the first annular boss, and is located at the right end of the front magnet ring 9; a radial mounting gap is provided between the left outer peripheral surface of the target substrate 10 and the inner peripheral surface of the front magnet ring 9, and the right end of the accelerating electrode 6 passes through the mounting gap and is installed on the left outer peripheral surface of the target substrate 10, while its outer peripheral surface abuts against the inner peripheral surface of the front magnet ring 9.

[0047] The target substrate 10 has an installation groove on its outer surface, and the heat dissipation structure is installed in the installation groove. Specifically, the heat dissipation structure is an oil circulation heat dissipation structure 11; an oil passage gap 19 is provided between the left end of the oil circulation heat dissipation structure 11 and the bottom of the installation groove, and two oil passage holes 20 are provided axially at the right end of the heat dissipation structure, both of which are connected to the oil passage gap 19. One oil passage hole 20 is connected to the output end of an external oil pump 15 through an insulating oil pipe 14, and the other oil passage hole 20 is connected to the input end of the oil pump 15 through an insulating oil pipe 14 and a radiator 16. See [reference needed]. Figure 2 Meanwhile, a second annular protrusion is provided on the outer peripheral surface of the heat dissipation structure, and the inner side of the second annular protrusion abuts against the right end of the target substrate 10 through a sealing ring 12.

[0048] The installation steps for the aforementioned high-yield deuterium-tritium neutron tube are as follows:

[0049] Step 1: Insert the heat dissipation ring 2 from the left end of the sealed outer shell.

[0050] Step 2: Insert the ion source assembly 3 into the heat dissipation ring 2 from the left end of the sealed shell. The stepped surface of the middle part of the ion source assembly 3 is in contact with the stepped surface of the heat dissipation ring 2. The outermost side of the left end of the ion source assembly 3 is in contact with the inner side of the left end of the ion source Kovar ring 1 of the sealed shell and the end faces are aligned. Then, perform argon arc welding to seal the connection.

[0051] Step 3: Insert the front magnet ring 9 of the target assembly from the right end of the sealed housing and fit it against the right end face of the target Kovar ring 8 of the sealed housing.

[0052] Step 4: Insert the accelerating electrode 6 from the right end of the sealed shell, so that the right end of the accelerating electrode 6 is in contact with the right end face of the front magnet ring 9.

[0053] Step 5: Insert the target substrate 10 of the target assembly from the right end of the sealed shell, so that the left end face of the target substrate 10 is in contact with the stepped surface inside the right end hole of the accelerating electrode 6. At the same time, the outermost side of the target substrate 10 is in contact with the inner side of the right end of the target Kovar ring 8 of the sealed shell, and the right ends of the two are aligned and sealed by argon arc welding.

[0054] Step 6: Connect the formed sealed neutron tube to the vacuum system through the oxygen-free copper tube at the left end of the ion source assembly 3, and perform a complete set of vacuum process treatment. After completion, cut and seal the oxygen-free copper tube.

[0055] Step 7: Insert the sealing ring 12 into the threaded step surface at the right end of the target base 10 of the target assembly, connect the oil circulation heat dissipation structure 11 of the target heat dissipation assembly through the thread, and press the sealing ring 12 tightly.

[0056] Step 8: Connect an external insulating oil circulation system through the two oil passages on the oil circulation heat dissipation structure 11.

[0057] The neutron generation method based on this high-yield deuterium-tritium neutron tube includes the following steps:

[0058] Step 1: Place the neutron tube in an environment that meets the requirements for high voltage insulation and neutron radiation protection safety.

[0059] Step 2: Connect an external power source to the external end of the ion source assembly 3, and connect an external heat dissipation system to the external end of the heat dissipation structure.

[0060] Step 3: Turn on the external power supply and the external cooling system;

[0061] Step 4: The external low-voltage power supply causes deuterium gas to be generated inside the ion source component 3. Under the ionization effect of the external high-voltage power supply, deuterium ions are generated. The deuterium ions are output from the inner end of the ion source component 3 to the acceleration gap 5. During this process, the heat generated by the ion source component 3 during ionization is transferred to the Kovar ring 1 of the ion source through the heat dissipation ring 2 to reduce the temperature rise of the ion source component 3.

[0062] Step 5: After accelerating the deuterium ions in the acceleration gap 5 through the acceleration electrode 6, the ions are output to the target assembly.

[0063] Step 6: High-energy neutron emission is generated by the target assembly under the deuterium-tritium nucleus reaction. During this process, the target assembly is subjected to external circulation forced heat dissipation through the heat dissipation structure to reduce the temperature rise of the target assembly.

Claims

1. A high-yield deuterium-tritium neutron tube, characterized in that: It includes an ion source Kovar ring (1), a connecting tube (4), a target Kovar ring (8), an ion source assembly (3), an accelerating electrode (6), a target assembly, and a heat dissipation structure; The ion source Kovar ring (1), the connecting tube (4), and the target Kovar ring (8) are coaxially connected in sequence; The ion source assembly (3) is installed inside the ion source Kovar ring (1) through the heat dissipation ring (2). Its outer end is used to connect to an external power source, and its inner end extends axially into the inner cavity of the connecting pipe (4). The ion source assembly (3) is used to ionize deuterium gas into deuterium ions under ionization and output them from its inner end. The target assembly is installed inside the target Kovar ring (8). One end of the accelerating electrode (6) is installed inside the target assembly, and an accelerating gap (5) is provided between the other end and the inside of the ion source assembly (3). The accelerating electrode (6) is used to accelerate deuterium ions and output them to the target surface (7) of the target assembly. The target assembly is used to generate high-energy neutron emission under the deuterium-tritium nucleus reaction. The heat dissipation structure is installed at the outer end of the target assembly and is used to connect to an external heat dissipation system to dissipate heat from the target assembly.

2. The high-yield deuterium-tritium neutron tube according to claim 1, characterized in that: The outer circumferential surface of the Kovar ring (1) of the ion source is provided with a plurality of heat dissipation ring grooves (21) distributed along the axial direction.

3. A high-yield deuterium-tritium neutron tube according to claim 2, characterized in that: The heat dissipation ring groove (21) is a rectangular ring groove.

4. A high-yield deuterium-tritium neutron tube according to any one of claims 1-3, characterized in that: The target assembly includes a front magnetic ring (9) and a target base (10); The inner diameter of the target Kovar ring (8) is larger than the inner diameter of the connecting pipe (4); The outer diameter of the front magnet ring (9) is adapted to the inner diameter of the target Kovar ring (8). The front magnet ring (9) is installed inside the target Kovar ring (8), with one end abutting against the outer end of the connecting pipe (4). The outer peripheral surface of the target base (10) is provided with a first annular protrusion. The outer diameter of the first annular protrusion is adapted to the inner diameter of the target Kovar ring (8). The target base (10) is installed in the target Kovar ring (8) through the first annular protrusion and is located at the other end of the front magnet ring (9). A radial installation gap is provided between the outer peripheral surface of the inner end of the target base (10) and the inner peripheral surface of the front magnet ring (9). One end of the accelerating electrode (6) passes through the installation gap and is installed on the outer peripheral surface of the inner end of the target base (10), while its outer peripheral surface abuts against the inner peripheral surface of the front magnet ring (9). The inner end face of the target substrate (10) is the target surface (7); The outer end face of the target substrate (10) is provided with an installation groove, and the heat dissipation structure is installed in the installation groove.

5. A high-yield deuterium-tritium neutron tube according to claim 4, characterized in that: The heat dissipation structure is an oil circulation heat dissipation structure (11); The input end of the oil circulation heat dissipation structure (11) is connected to the output end of an external oil pump (15), and the output end is connected to the input end of the oil pump (15) via a radiator (16).

6. A high-yield deuterium-tritium neutron tube according to claim 5, characterized in that: An oil passage gap (19) is provided between the inner end of the oil circulation heat dissipation structure (11) and the bottom of the mounting groove. Two oil passage holes (20) are provided along the axial direction at the outer end of the heat dissipation structure, both of which are connected to the oil passage gap (19). One of the oil passage holes (20) is connected to the output end of the external oil pump (15), and the other oil passage hole (20) is connected to the input end of the oil pump (15) via the radiator (16).

7. A high-yield deuterium-tritium neutron tube according to claim 6, characterized in that: A second annular protrusion is provided on the outer peripheral surface of the heat dissipation structure, and the inner side of the second annular protrusion abuts against the outer end of the target substrate (10) through a sealing ring (12).

8. A high-yield deuterium-tritium neutron tube according to claim 1, characterized in that: The ion source Kovar ring (1), the connecting tube (4), and the target Kovar ring (8) are sequentially welded by vacuum brazing; The connecting pipe (4) is an externally corrugated ceramic pipe.

9. A high-yield deuterium-tritium neutron tube according to claim 1 or 8, characterized in that: The outer end of the ion source assembly (3) is provided with three sealed and insulated terminals (17) and a sealed oxygen-free copper tube (18); Two of the sealed insulating terminals (17) are used to connect to the low-voltage power supply for external heating, and the third sealed insulating terminal (17) is used to connect to the high-voltage power supply for external anode. The oxygen-free copper tube (18) is used to connect to an external vacuum device during vacuuming.

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