Beryllium sleeve, reactor core assembly and research reactor irradiation test device

Abstract

The invention relates to the technical field of nuclear engineering, in particular to a beryllium sleeve, a reactor core assembly and a research reactor irradiation test device. The beryllium sleeve comprises a supporting piece, a beryllium block, a first fixing block and a second fixing block. The supporting piece is provided with a reactor core channel suitable for neutrons to pass through; a plurality of beryllium blocks are attached to the supporting piece, the beryllium blocks are adjacently arranged in the circumferential direction of the reactor core channel so as to surround the reactor core channel in the circumferential direction, the beryllium blocks are adjacently arranged in the extending direction of the reactor core channel so as to cover the reactor core channel in the axial direction, and aluminum pieces are arranged between the adjacent beryllium blocks in a matched mode; the first fixing block is matched with the supporting piece and the beryllium block; the second fixing block is matched with the supporting piece and the beryllium block. The beryllium sleeve is high in structural stability and reliability, neutrons can be effectively reflected to slow down quantity attenuation of the neutrons when the beryllium sleeve is combined with a reactor core assembly to be applied to a research reactor irradiation test device, neutron adsorption is reduced in cooperation with an aluminum piece, and neutron economy is improved.

Description

Technical Field

[0001] The present application relates to the field of nuclear engineering technology, and in particular to a beryllium sleeve, a core assembly and a research reactor irradiation test device. Background Art

[0002] Research reactors are nuclear reactors used for research, development, education, and training. The neutrons produced by research reactors can be used for research in the fields of materials, chemistry, isotopes, and medicine. Therefore, research reactors are an important means of developing atomic energy technology. Since beryllium materials have weak neutron adsorption and strong reflection capabilities, beryllium blocks made of beryllium materials provide core channels for irradiation test devices, which can effectively slow down the attenuation of neutron numbers and improve neutron economy. However, beryllium blocks are made through powder metallurgy and are prone to brittle fracture. Beryllium materials alone cannot form a reliable and stable structure. Summary of the invention

[0003] The present application provides a beryllium sleeve, a core assembly and a research reactor irradiation test device, wherein a core channel is provided through a support member, and beryllium blocks are arranged on the support member so that the beryllium blocks form an enclosure around the core channel, neutrons are reflected by the beryllium blocks to slow down the attenuation of the neutron number, thereby avoiding the method of directly using beryllium components to provide the core channel, and the overall structure is stable and reliable.

[0004] This application is implemented through the following technical solutions:

[0005] In a first aspect, the present application provides a beryllium sleeve, comprising:

[0006] A support member having a core channel suitable for neutrons to pass through;

[0007] Beryllium blocks, a plurality of beryllium blocks are attached to the support member, wherein, in the circumferential direction of the core channel, the beryllium blocks are arranged adjacent to each other to enclose the core channel in the circumferential direction, and in the extending direction of the core channel, the beryllium blocks are arranged adjacent to each other to cover the core channel in the axial direction, and aluminum parts are provided between adjacent beryllium blocks;

[0008] a first fixing block, the first fixing block cooperates with the supporting member and cooperates with the beryllium block;

[0009] A second fixing block, the second fixing block cooperates with the supporting member and cooperates with the beryllium block.

[0010] In some optional embodiments, the aluminum member is configured as an aluminum sleeve, which is sleeved on the support member and respectively engages with adjacent beryllium blocks.

[0011] In some optional embodiments, the first fixing block and the second fixing block are respectively sleeved on the supporting member.

[0012] In some optional embodiments, the first fixing block and the second fixing block are respectively engaged with the beryllium block.

[0013] In some optional embodiments, water holes are respectively constructed on the beryllium block, the aluminum part, the first fixed block and the second fixed block, the water holes of adjacent beryllium blocks are connected, the water holes of the aluminum part are connected to the water holes of adjacent beryllium blocks, the water holes of the first fixed block are connected to the water holes of its adjacent beryllium blocks, and the water holes of the second fixed block are connected to the water holes of its adjacent beryllium blocks.

[0014] In some optional embodiments, a baffle is further included, wherein the baffle has a first fitting surface, and the baffle is fitted with the support member via the first fitting surface to remain relatively fixed with the support member, and in the extension direction of the core channel, the baffle is located on one side of the second fixed block.

[0015] In some optional embodiments, in the cross section of the core channel, the contour shape of the structure formed by combining all the beryllium blocks is non-circular.

[0016] In some optional embodiments, on the cross section of the core channel, the contour shape of the structure formed by combining all the beryllium blocks is a broken line.

[0017] In some optional embodiments, a lifting interface suitable for cooperation with lifting equipment is provided at one end of the support member in the extension direction.

[0018] In some optional embodiments, a positioning pin is further included, wherein the positioning pin has a second fitting surface, and the positioning pin is fitted with the support member through the second fitting surface to remain relatively fixed with the support member, and in the extension direction of the core channel, the positioning pin is located on one side of the first fixed block.

[0019] In a second aspect, the present application provides a core assembly for cooperating with the beryllium sleeve described in the first aspect, wherein the core assembly has a cooperating cavity having an inner wall adapted to the shape of the beryllium block, wherein a gap is provided between the beryllium block and the inner wall.

[0020] In a third aspect, the present application provides a research reactor irradiation test device, comprising the beryllium sleeve described in the first aspect and the core assembly described in the second aspect.

[0021] Compared with the prior art, this application has the following advantages and beneficial effects:

[0022] 1. A beryllium sleeve provided in the present application can provide stable support for the entire beryllium sleeve through a support member to ensure the reliability and stability of the overall structure. After a plurality of beryllium blocks are matched with the support member, a core channel on the support member can be enclosed, so that the beryllium blocks can reflect neutrons in the core channel, and the attenuation of the number of neutrons after passing through the core channel is slowed down; the provision of the first fixed block and the second fixed block can improve the structural stability between the beryllium blocks and the support member, thereby further ensuring the stability and reliability of the overall structure of the beryllium sleeve, and further ensuring the effect of slowing down the attenuation of the number of neutrons after passing through the core channel.

[0023] 2. The present application provides a beryllium sleeve, which is a neutron reflection structure formed by combining multiple beryllium blocks. Compared with the method of directly providing a core channel through the entire beryllium material component, when the function of one or several beryllium blocks is reduced or fails, the single or multiple beryllium blocks can be replaced independently, and the maintenance cost is greatly reduced.

[0024] 3. A core assembly provided in the present application can form a water gap with the beryllium sleeve provided in the present application after being matched with the beryllium sleeve, so that the cooling medium can cool the beryllium sleeve in the water gap to avoid excessive thermal stress affecting the beryllium block.

[0025] 4. The present application provides a research reactor irradiation test device, which uses the core assembly and beryllium sleeve provided in the present application to provide a core channel for neutrons. After the neutrons pass through the core channel, the attenuation of their number is slowed down, which can improve the neutron economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 A schematic diagram of the structure of a beryllium sleeve provided in an embodiment of the present application;

[0028] Figure 2 This is a schematic diagram of the coordination structure of the beryllium sleeve and the core assembly in the research reactor irradiation test device provided in an embodiment of the present application.

[0029] Marks and corresponding parts names in the attached drawings:

[0030] 1-support, 2-first fixed block, 3-aluminum part, 4-beryllium block, 5-block, 6-locating pin, 7-second fixed block, 8-water flow hole, 9-lifting interface, 10-core assembly, 11-beryllium sleeve, 12-water gap. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with examples and drawings. The illustrative implementation scheme of the present application and its description are only used to explain the present application and are not intended to limit the present application.

[0032] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present application. However, it is apparent to those of ordinary skill in the art that these specific details do not need to be adopted to practice the present application. In other embodiments, in order to avoid confusing the present application, well-known structures, circuits, materials or methods are not specifically described.

[0033] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment of the present application. Therefore, the phrases "one embodiment," "an embodiment," "an example," or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. In addition, it will be appreciated by those of ordinary skill in the art that the figures provided herein are for illustrative purposes and that the figures are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0034] In the description of the present application, the terms "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the scope of protection of the present application.

[0035] First, see Figure 1 An embodiment of the present application provides a beryllium sleeve, including a support member 1, a beryllium block 4, a first fixing block 2 and a second fixing block 7.

[0036] The support member 1 serves as a support member of the beryllium sleeve on one hand, and provides a core channel for neutrons on the other hand, that is, a core channel is constructed on the support member 1 for neutrons to pass through. The overall shape of the support member 1 may not be limited, such as square, prism, truncated cone, cylindrical, etc. Considering the space saving and easy processing and manufacturing, the overall shape of the support member 1 may be set to cylindrical; the cross-sectional shape of the core channel may not be limited. In actual implementation, the cross-sectional shape of the core channel may be set to circular, that is, the overall structure of the support member 1 may be tubular.

[0037] A plurality of beryllium blocks 4 are attached to the support 1. Specifically, the beryllium blocks 4 can be constructed into a long strip shape. When the support 1 is constructed into a circular tube, the surface of the beryllium block 4 that is attached to the support 1 can be constructed into an arc surface to form a larger contact area with the support 1, thereby being able to ensure the relative stability of the beryllium block 4 and the support 1 to a certain extent. The length direction of the beryllium block 4 is parallel to the axial direction of the support 1. In the circumferential direction of the core channel, the beryllium blocks 4 are arranged adjacent to each other to form an enclosure for the core channel in the circumferential direction, that is, in the radial section of the support 1 On the upper surface, each beryllium block 4 is connected end to end, and the surfaces of all beryllium blocks 4 that are in contact with the support member 1 together form a closed circle; in the extension direction of the core channel, the beryllium blocks 4 are arranged adjacent to each other to cover the core channel in the axial direction, that is, in the axial direction of the support member 1, the beryllium blocks 4 are arranged in sequence, wherein every two adjacent beryllium blocks 4 are connected through the aluminum member 3, and in the axial perspective of the support member 1, the contour shape of the aluminum member 3 coincides with the contour shape of the beryllium block 4, and the arrangement of the aluminum member 3 can effectively reduce neutron adsorption and improve the neutron economy to a certain extent.

[0038] The first fixed block 2 mainly serves as one of the limiting components of the beryllium block 4 in the axial direction of the support member 1. The first fixed block 2 cooperates with the support member 1 so that the first fixed block 2 can form a relatively fixed state with the support member 1. The first fixed block 2 is located at one axial end of the support member 1. The first fixed block 2 cooperates with the beryllium block 4 close to the axial end, so that the first fixed block 2 and the beryllium block 4 form a relatively fixed state in the circumferential direction of the support member 1.

[0039] The second fixed block 7 mainly serves as another limiting component of the beryllium block 4 in the axial direction of the support member 1. The second fixed block 7 cooperates with the support member 1 so that the second fixed block 7 can form a relatively fixed state with the support member 1. The second fixed block 7 is located at the other axial end of the support member 1. The second fixed block 7 cooperates with the beryllium block 4 close to the other axial end, so that the second fixed block 7 and the beryllium block 4 form a relatively fixed state in the circumferential direction of the support member 1.

[0040] Compared with the method commonly used in the art: directly processing beryllium components into core channel components, since beryllium components are made by powder metallurgy process, they are prone to brittle fracture, so longer beryllium components also make the overall stability and reliability of the structure lower. The beryllium sleeve provided in the embodiment of the present application uses the support member 1 to support the entire structure, and the beryllium sleeve as a whole has a certain structural stability and reliability, and multiple beryllium blocks 4 are arranged outside the support member 1 to surround the core channel to effectively reflect neutrons, the length of a single beryllium block 4 is reduced, and the beryllium block 4 is not prone to brittle fracture, and the first fixed block 2 and the second fixed block 7 can improve the structural stability of the beryllium block 4 and the support member 1, thereby further ensuring the stability and reliability of the overall structure of the beryllium sleeve. At the same time, in the circumferential direction of the support 1, a neutron reflection structure is formed by connecting multiple beryllium blocks 4 end to end. Each beryllium block 4 uses less material. When the function of part of the reflection structure is reduced or fails, the function of the reflection structure can be completed by replacing the local beryllium block 4, which is easy to maintain. Compared with the method of directly processing and manufacturing beryllium material components into core channel components, the maintenance process consumes less materials. That is to say, when the beryllium material components are directly processed and manufactured into core channel components, if the local structure has reduced function or fails, the entire component needs to be replaced for maintenance, and the maintenance cost is higher. Among them, in the axial direction of the support 1, every two adjacent beryllium blocks 4 are also matched by aluminum parts 3, and aluminum parts 3 can reduce the adsorption of neutrons, thereby further improving the neutron economy.

[0041] In some optional embodiments, the aluminum member 3 is configured as an aluminum sleeve ring, which is sleeved on the support member 1 and respectively meshed with adjacent beryllium blocks 4. Providing the aluminum member 3 as an aluminum sleeve ring can facilitate the assembly of the aluminum member 3 and the support member 1, and at the same time, the aluminum member 3 has structural continuity in the circumferential direction of the support member 1, and the effect of reducing neutron adsorption is better.

[0042] In some optional embodiments, the first fixing block 2 and the second fixing block 7 are respectively sleeved on the support member 1. That is, when the support member 1 is configured in a round tube shape, the first fixing block 2 and the second fixing block 7 are also respectively provided with matching holes adapted to the outer diameter of the support member 1, and the first fixing block 2 and the second fixing block 7 form a transition fit with the support member 1 through their respective matching holes, so that the first fixing block 2 and the second fixing block 7 have a larger contact area with the support member 1, and the first fixing block 2 and the second fixing block 7 can improve the structural stability of the support member 1 to a certain extent.

[0043] In actual implementation, in the axial direction of the support member 1, the contour shadow of the beryllium block 4 can completely overlap with the contour shadows of the first fixed block 2 and the second fixed block 7, thereby facilitating the assembly of the beryllium sleeve and the core assembly, that is, the hole type on the core assembly for the beryllium sleeve to pass through can be constructed as a straight hole.

[0044] In some optional embodiments, the first fixing block 2 and the second fixing block 7 are respectively engaged with the beryllium block 4. After the first fixing block 2 and the second fixing block 7 are connected with the beryllium block 4 in an engaged manner, it is easy to separate the first fixing block 2, the second fixing block 7 from the beryllium block 4, thereby facilitating the disassembly of the beryllium block 4, especially in the remote disassembly workflow, the engagement method can greatly improve the separation efficiency, thereby improving the disassembly efficiency.

[0045] In some optional embodiments, when there are two beryllium blocks 4 in the axial direction of the support member 1, the two beryllium blocks 4 may not be connected, and the two beryllium blocks 4 may be arranged by end-face bonding. When there are three or more beryllium blocks 4, two adjacent beryllium blocks 4 may be connected by meshing, so that the first fixing block 2 and the second fixing block 7 can limit the circumferential direction of the core channel for all beryllium blocks 4.

[0046] The meshing in the embodiment of the present application can be achieved through a tooth meshing structure.

[0047] In some optional embodiments, water holes 8 are respectively constructed on the beryllium block 4, the aluminum part 3, the first fixed block 2 and the second fixed block 7, the water holes 8 of adjacent beryllium blocks 4 are connected, the water holes 8 of the aluminum part 3 are connected with the water holes 8 of adjacent beryllium blocks 4, the water holes 8 of the first fixed block 2 are connected with the water holes 8 of its adjacent beryllium block 4, and the water holes 8 of the second fixed block 7 are connected with the water holes 8 of its adjacent beryllium block 4, so that the water holes 8 on the first fixed block 2, the beryllium block 4, the aluminum part 3 and the second fixed block 7 together form a through water flow channel, and cooling water can flow in the water flow channel to dissipate the heat of the beryllium block 4 from the inside, thereby preventing the beryllium block 4 from having excessive thermal stress and causing excessive impact on the beryllium block 4.

[0048] Among them, on the radial cross section of the support member 1, the shape profile of the water flow hole 8 can be constructed as a crescent shape. The crescent-shaped water flow hole 8 has a larger contact area, and the cooling water can flow more quickly in the water flow hole 8, and the heat in the beryllium block 4 can be quickly taken away, thereby improving the heat dissipation efficiency of the beryllium block 4.

[0049] In some optional embodiments, the beryllium sleeve further includes a baffle 5, which has a first fitting surface, and the baffle 5 fits with the support member 1 through the first fitting surface to keep relatively fixed with the support member 1. When the support member 1 is set as a circular tube structure, the first fitting surface here is an arc surface, and the cross-sectional shape of the entire baffle 5 can be set to a crescent shape. In the extension direction of the core channel, the baffle 5 is located on one side of the second fixed block 7, and there is a certain gap between the baffle 5 and the second fixed block 7 so that cooling water can enter the water flow hole 8 of the second fixed block 7. The setting of the baffle 5 can reduce the scouring strength of the cooling water on the second fixed block 7 to a certain extent, thereby ensuring the connection stability between the second fixed block 7 and the support member 1, and further ensuring the overall structural stability of the beryllium sleeve.

[0050] In some optional embodiments, on the cross section of the core channel, the contour shape of the structure composed of all beryllium blocks 4 is non-circular. That is, in the axial perspective of the core channel, the outer contour shape of the reflective structure composed of beryllium blocks 4 is non-circular, so that the reflective structure as a whole can have an outer surface with a larger area as much as possible, which is conducive to the rapid dissipation of heat. In actual implementation, the cross-sectional shape of a single beryllium block 4 in the axial direction of the support 1 can be set to a trapezoidal shape. The trapezoidal shape here refers to a trapezoid, for example, where the long bottom side fits the outer wall of the support 1 in an arc. At this time, the contour shape of the reflective structure as a whole is a broken line, which has a larger outer surface area and can ensure that it has a better heat dissipation effect. At the same time, after the contour shape of the reflective structure as a whole is set to a broken line, it can have multiple straight edges and corners, which is easier to disperse external forces, and its bending and torsion resistance is better. The presence of the corners can also resist compression and shear forces, so that the reflective structure as a whole has higher strength and stability.

[0051] In some optional embodiments, a lifting interface 9 suitable for the lifting equipment is provided at one end of the support member 1 in the extension direction. Preferably, the lifting interface 9 can be provided as a bayonet type so as to facilitate the lifting equipment to cooperate with the support member 1.

[0052] In some optional embodiments, the beryllium sleeve further includes a positioning pin 6, which has a second fitting surface. The positioning pin 6 fits with the support member 1 through the second fitting surface to maintain relative fixation with the support member 1. When the support member 1 is set as a circular tube structure, the second fitting surface here is an arc surface, and the cross-sectional shape of the entire positioning pin 6 can be set to a crescent shape. The positioning pin 6 can cooperate with the core assembly to form a pin connection, thereby facilitating the remote positioning operation of the beryllium sleeve and the core assembly. In the extension direction of the core channel, the positioning pin 6 is located on one side of the first fixed block 2. Preferably, a guide surface can be set at the end of the positioning pin 6 to facilitate the plug-in fit of the positioning pin 6 and the core assembly; for example, the end of the positioning pin 6 can be configured as a cone.

[0053] In a second aspect, an embodiment of the present application provides a core assembly for cooperating with the beryllium sleeve of the first aspect, the core assembly having a cooperating cavity having an inner wall adapted to the shape of the beryllium block 4, wherein a gap is provided between the beryllium block 4 and the inner wall.

[0054] The core assembly also has a positioning hole suitable for inserting the positioning pin 6 and a matching groove adapted to the shape of the choke plug 5, so that the choke plug 5 and the positioning pin 6 on the beryllium sleeve can play a positioning role together.

[0055] Third, see Figure 2 , the embodiment of the present application provides a research reactor irradiation test device, including any one of the beryllium sleeves 11 of the first aspect and the core assembly 10 of the second aspect. After the beryllium sleeve 11 and the core assembly 10 are assembled, since the contour shape of the beryllium sleeve 11 in the axial perspective of the core channel is a broken line, a water gap 12 with a large cross-sectional area can be formed between the two. The cooling water can efficiently cool the outer wall of the beryllium block 4 when flowing through the water gap 12. Combined with the setting of the water flow holes 8 on the beryllium block 4, the heat dissipation efficiency of the beryllium block 4 can be further improved, thereby preventing excessive thermal stress from affecting the beryllium block 4.

[0056] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the present application in detail. It should be understood that the above description is only the specific implementation method of the present application and is not intended to limit the scope of protection of the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A beryllium sleeve, characterized in that: include: A support member (1), the support member (1) having a core channel suitable for neutrons to pass through; Beryllium blocks (4), a plurality of beryllium blocks (4) are attached to the support member (1), wherein in the circumferential direction of the core channel, the beryllium blocks (4) are arranged adjacent to each other to enclose the core channel in the circumferential direction, and in the extending direction of the core channel, the beryllium blocks (4) are arranged adjacent to each other to cover the core channel in the axial direction, and an aluminum member (3) is provided between adjacent beryllium blocks (4); A first fixing block (2), the first fixing block (2) cooperates with the support member (1) and cooperates with the beryllium block (4); A second fixing block (7), the second fixing block (7) cooperates with the support member (1) and cooperates with the beryllium block (4).

2. The beryllium sleeve according to claim 1, characterized in that: The aluminum part (3) is configured as an aluminum sleeve ring, and the aluminum part (3) is sleeved on the support part (1) and respectively meshes with adjacent beryllium blocks (4).

3. The beryllium sleeve according to claim 1, characterized in that: The first fixing block (2) and the second fixing block (7) are respectively sleeved on the supporting member (1).

4. The beryllium sleeve according to claim 1, characterized in that: The first fixing block (2) and the second fixing block (7) are respectively engaged with the beryllium block (4).

5. The beryllium sleeve according to claim 1, characterized in that: The beryllium block (4), the aluminum part (3), the first fixed block (2) and the second fixed block (7) are respectively provided with water flow holes (8); the water flow holes (8) of adjacent beryllium blocks (4) are connected; the water flow hole (8) of the aluminum part (3) is connected to the water flow hole (8) of the adjacent beryllium block (4); the water flow hole (8) of the first fixed block (2) is connected to the water flow hole (8) of the adjacent beryllium block (4); and the water flow hole (8) of the second fixed block (7) is connected to the water flow hole (8) of the adjacent beryllium block (4).

6. The beryllium sleeve according to claim 5, characterized in that: The invention also comprises a baffle (5), wherein the baffle (5) has a first fitting surface, and the baffle (5) fits with the support member (1) via the first fitting surface so as to remain relatively fixed with the support member (1); in the extension direction of the core channel, the baffle (5) is located on one side of the second fixing block (7).

7. The beryllium sleeve according to claim 1, characterized in that: In the cross section of the core channel, the outline shape of the structure formed by combining all the beryllium blocks (4) is non-circular.

8. The beryllium sleeve according to claim 7, characterized in that: On the cross section of the core channel, the outline shape of the structure formed by combining all the beryllium blocks (4) is a broken line.

9. The beryllium sleeve according to claim 1, characterized in that: One end of the support member (1) in the extension direction is provided with a lifting interface (9) suitable for cooperation with lifting equipment.

10. The beryllium sleeve according to claim 1, characterized in that: It also includes a positioning pin (6), the positioning pin (6) having a second fitting surface, the positioning pin (6) fitting with the support member (1) via the second fitting surface to remain relatively fixed with the support member (1), and in the extension direction of the core channel, the positioning pin (6) is located on one side of the first fixing block (2).

11. A core assembly, used for cooperating with the beryllium sleeve according to any one of claims 1 to 10, characterized in that: The core assembly has a matching cavity, the matching cavity has an inner wall adapted to the shape of the beryllium block (4), wherein a gap is provided between the beryllium block (4) and the inner wall.

12. A research reactor irradiation test device, characterized in that: It comprises the beryllium sleeve (11) according to any one of claims 1 to 10 and the core assembly (10) according to claim 11.

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