Flat plate type divertor module suitable for magnetic confinement fusion reactor and preparation method of flat plate type divertor module

Abstract

The invention provides a flat plate type divertor module suitable for a magnetic confinement fusion reactor and a preparation method of the flat plate type divertor module, and aims to solve the problems that an existing divertor is difficult to keep stable performance and complete structure and is insufficient in heat dissipation efficiency in a high-heat-flux and high-energy neutron irradiation environment of the fusion reactor. The module comprises a composite heat sink and a tungsten copper composite part fixed on the surface of the composite heat sink, the composite heat sink is composed of a copper alloy layer, a structural material layer and a cover plate, a cooling flow channel is arranged between the copper alloy layer and the structural material layer, and a water inlet and outlet pipe is arranged on the cover plate and connected with the cooling flow channel to achieve efficient heat exchange. The tungsten-copper composite part is composed of plasma-facing material pure tungsten (5mm) and an oxygen-free copper middle layer, the copper alloy layer is made of an aluminum oxide dispersion strengthened copper material (ODSCU), and the structural material layer and the cover plate are made of low-activation ferrite / martensitic steel (CLF-1). According to the preparation method, explosive welding, vacuum hot-pressing diffusion welding, vacuum brazing and the like are adopted, reliable connection of different materials is achieved, and the heat dissipation capacity and structural integrity of the module under the conditions of high heat flux and neutron irradiation are guaranteed. The high-temperature-resistant radiation-resistant fusion reactor divertor has excellent high-temperature-resistant and radiation-resistant performance, and is suitable for long-life use in a high-heat-load area of the fusion reactor divertor.

Description

Technical Field

[0001] The invention belongs to the technical field of magnetic confinement fusion reactor divertors, and relates to a flat-plate divertor module suitable for a magnetic confinement fusion reactor and a preparation method thereof. Background Art

[0002] The magnetic confinement nuclear fusion tokamak device is considered to be the most promising magnetic confinement nuclear fusion device for achieving controlled nuclear fusion. An important scientific goal of future tokamak fusion reactors is to achieve steady-state operation of high-parameter and high-performance plasma. In this operating mode, the combined effects of high particle flux, high heat load, high-energy neutron irradiation, strong thermal stress, and electromagnetic force will have a significant impact on the performance and structure of the divertor. Therefore, the divertor must have the ability to efficiently transfer heat and maintain the integrity of the mechanical structure. Among them, the most serious are the effects of neutron irradiation and high heat load. The current divertor structure and preparation process cannot meet the use requirements of fusion reactors. Due to the differences in magnetic field configurations and the influence of plasma transmission characteristics, the heat load deposited on the divertor presents an uneven distribution. The high heat load area needs to withstand up to 20MW / m 2 The heat load will increase the surface temperature of the material facing the plasma, which is prone to damage such as cracks and ablation. In order to quickly and effectively remove the heat load deposited on the divertor surface, an efficient heat exchange structure and preparation process must be used to reduce the temperature of the divertor surface, ensure the reliability of the structure, and effectively extend the service life of the divertor.

[0003] Chinese patent application publication number CN114038581A introduces a flat divertor target plate suitable for a magnetic confinement nuclear fusion device and a processing method thereof. The thickness of the plasma-facing tungsten material of the invention is 2 mm, and a chromium-zirconium-copper (CuCrZr) metal plate and a 316L steel plate are used as heat sinks. The prepared divertor target plate can be used in the high heat load area of ​​the current nuclear fusion device. However, in a fusion reactor environment, the fusion reaction will produce 14MeV high-energy neutrons, which will cause serious damage to the above-mentioned materials, resulting in a sharp decline in material performance. Therefore, in order to meet the special use requirements of fusion reactors, high-performance radiation-resistant divertor materials must be used. At the same time, since the plasma-facing tungsten material will be sputtered and eroded during operation, this will cause the tungsten material to become thinner and its life will be reduced, so the 2mm tungsten has the disadvantage of a low etching life.

[0004] Therefore, there is an urgent need to develop a new type of divertor target plate, which is specially designed for the high heat load area of ​​the fusion reactor divertor, aiming to ensure the material performance and achieve efficient heat dissipation while ensuring the integrity and stability of the mechanical structure, thereby extending its service life. Summary of the invention

[0005] In view of this, an object of the present invention is to solve the above-mentioned problem and provide a flat-plate divertor module suitable for a magnetic confinement fusion reactor and a preparation method thereof.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A flat-plate divertor module suitable for a magnetic confinement fusion reactor comprises a composite heat sink and a plurality of tungsten-copper composite parts fixed on the surface of the composite heat sink;

[0008] The composite heat sink comprises a copper alloy layer, a structural material layer, and a cover plate which are sequentially arranged in layers, and the tungsten-copper composite member is arranged on the surface of the copper alloy layer;

[0009] A heat exchange cooling channel is provided between the copper alloy layer and the structural material layer; a water inlet pipe and a water outlet pipe are provided on the cover plate, and both the water inlet pipe and the water outlet pipe are connected to the heat exchange cooling channel;

[0010] The tungsten-copper composite component is composed of a plasma-facing material layer and an oxygen-free copper intermediate layer, wherein the plasma-facing material layer is located on the outside;

[0011] The plasma-facing material layer is pure tungsten with a thickness of 5 mm, and the oxygen-free copper intermediate layer is 0.5-1 mm thick; the copper alloy layer is made of alumina dispersion-strengthened copper material (ODS_Cu), the structural material layer is made of low-activated ferrite / martensitic steel (CLF-1), and the cover plate, water inlet pipe and water outlet pipe are all made of CLF-1.

[0012] Furthermore, the copper alloy layer and the structural material layer are composited by using an explosion welding process.

[0013] Furthermore, the plasma-facing material layer and the oxygen-free copper intermediate layer are connected by casting-assisted vacuum hot pressing diffusion welding.

[0014] Furthermore, the composite heat sink is connected to the tungsten-copper composite component by a vacuum brazing process, and the brazing material is a silver-free brazing material.

[0015] Furthermore, the cooling channel is based on a typical hypervapotron structure, and the copper alloy layer is provided with evenly distributed rectangular fin-shaped inner fins; a coolant is passed through the cooling channel, which can remove 20MW / m 2 of heat flow.

[0016] A method for preparing the flat-plate divertor module suitable for a magnetic confinement fusion reactor as described above comprises the following steps:

[0017] S1. Based on the size requirements of the divertor, an ODS_Cu alloy metal plate and a CLF-1 steel metal plate are placed in parallel and processed into a composite bimetallic composite plate by explosion welding process; then the performance of the composite plate is tested;

[0018] S2. After the composite plate performance test meets the requirements, a cooling channel with parallel inner fins is machined on the composite plate by electric spark or machining;

[0019] S3. Pre-open holes on the cover plate for installing the water inlet pipe and the water outlet pipe, and use argon arc welding technology to cover the cover plate on the composite plate for sealing;

[0020] S4, casting the molten oxygen-free copper onto the surface of pure tungsten, and then vacuum hot pressing it in a vacuum hot pressing furnace, and then machining it into the required size of the tungsten-copper composite part;

[0021] S5, after the composite heat sink surface processed in step S3, a plurality of tungsten-copper composite parts prepared in step S4 are seamlessly welded to the surface of the alumina dispersion-strengthened copper alloy metal plate of the heat sink by vacuum brazing;

[0022] S6. Finally, the water inlet pipe and the water outlet pipe are connected to the reserved hole positions on the cover plate by using argon arc welding process, so as to obtain a complete divertor target plate module.

[0023] Furthermore, the composite plate prepared in step S1 is subjected to interface nondestructive testing and helium leakage testing.

[0024] The beneficial effects of the present invention are:

[0025] (1) Different from the CuCrZr and 316L steel materials used in the prior art, the flat divertor target plate material of the present invention uses high-performance radiation-resistant materials ODS_Cu and CLF-1 steel, which can still maintain good performance under neutron irradiation in a fusion reactor.

[0026] (2) The heat sink of the flat divertor target plate in the present invention adopts a composite heat sink composed of a bimetallic plate. A copper alloy material with excellent thermal conductivity is selected for the side facing the plasma material, and a steel-based material with excellent mechanical properties and welding properties is selected for the other side, so that the heat dissipation and structural reliability requirements of the divertor can be met at the same time.

[0027] (3) The thickness of the pure tungsten material facing the plasma of the flat divertor target plate in the present invention is designed to be 5 mm, which has a longer etching life than the 2 mm used in the existing divertor, and can effectively extend the service life of the divertor.

[0028] (4) The present invention adopts an optimized hypervapotron structure, which has excellent heat exchange capacity and ultra-high critical heat flux density, can greatly reduce the surface temperature of the divertor and extend the service life of the divertor;

[0029] (5) Silver-free solder is used between the composite heat sink and the tungsten-copper composite part in the present invention. Since there is a small amount of Al2O3 in the oxide-dispersed copper alloy, when welding with copper, the interface wetting angle between the two is large and the wettability is poor. In addition, considering the environment of the fusion reactor, the silver-copper solder commonly used to connect copper alloys cannot be used, which greatly increases the difficulty of welding between the copper in the tungsten-copper composite part and the oxide-dispersed copper alloy on one side of the composite heat sink. The present invention uses a silver-free solder - copper-tin-titanium for vacuum brazing.

[0030] (6) The divertor structure and preparation process adopted in the present invention can improve the heat dissipation performance and structural reliability of the divertor, and can withstand up to 20MW / m 2 of heat flow.

[0031] In summary, the present invention solves the current problems of insufficient heat dissipation capacity and difficult preparation of the divertor from two aspects of structural design and preparation process, and can significantly improve the heat dissipation capacity and service life of the divertor.

[0032] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0034] Figure 1 It is an overall schematic diagram of a flat-plate divertor module suitable for a magnetic confinement fusion reactor in the present invention.

[0035] Figure 2 It is a cross-sectional view of a flat-plate divertor module in the present invention.

[0036] Figure 3 The figure is a flow chart of the preparation method of the present invention.

[0037] Figure numerals: 1-tungsten copper composite; 2-copper alloy layer; 3-structural material layer; 4-cover plate; 5-water inlet pipe; 6-water outlet pipe; 11-plasma-facing material layer; 12-oxygen-free copper intermediate layer. DETAILED DESCRIPTION

[0038] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0039] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0040] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0041] See also Figures 1-2 , which is a flat-plate divertor module suitable for a magnetic confinement fusion reactor, comprising a composite heat sink and a plurality of tungsten-copper composites 1 fixed on the surface of the composite heat sink; the composite heat sink comprises a copper alloy layer 2, a structural material layer 3, and a cover plate 4 which are sequentially arranged in layers, and the tungsten-copper composite 1 is arranged on the surface of the copper alloy layer 2; a heat exchange cooling channel is arranged between the copper alloy layer 2 and the structural material layer 3; a water inlet pipe 5 and a water outlet pipe 6 are arranged on the cover plate 4, and both the water inlet pipe 5 and the water outlet pipe 6 are connected to the heat exchange cooling channel; the tungsten-copper composite 1 is composed of a plasma-facing material layer 11 and an oxygen-free copper intermediate layer 12, and the plasma-facing material layer 11 is located on the outside.

[0042] Among them, the plasma-facing material layer 11 is pure tungsten with a thickness of 5 mm, and the oxygen-free copper intermediate layer 12 is 0.5-1 mm thick; the copper alloy layer 2 adopts alumina dispersion-strengthened copper material, the structural material layer 3 adopts low-activated ferrite / martensitic steel, and the cover plate 4, the water inlet pipe 5 and the water outlet pipe 6 all adopt low-activated ferrite / martensitic steel.

[0043] In this embodiment, the copper alloy layer 2 and the structural material layer 3 are composited by explosion welding process. The plasma-facing material layer 11 and the oxygen-free copper intermediate layer 12 are connected by casting-assisted vacuum hot pressing diffusion welding. The composite heat sink is connected to the tungsten-copper composite part 1 by vacuum brazing process, and the brazing material is silver-free brazing material. The cooling channel is based on the typical ultra-super evaporative cooler structure, and the copper alloy layer 2 is provided with evenly distributed rectangular fin-shaped inner fins; the cooling channel is passed with coolant, which can remove 10-20MW / m 2 of heat flow.

[0044] See also Figure 3 The method for preparing the flat-plate divertor module in this embodiment comprises the following steps:

[0045] Step S1, based on the size requirements of the divertor, first select an ODS_Cu alloy metal plate and a CLF-1 steel metal plate. Before explosive welding, remove the oxide film, grease and other impurities on the surfaces of the two metal plates to be combined, and polish them, then clean and dry them. Next, place the ODS_Cu metal plate on the foundation, install a support column on it, then place the CLF-1 steel plate on the top of the support column, and evenly lay explosives on the CLF-1 steel. A parallel arrangement is adopted with an inclination angle of 0 degrees. Then explosive welding is performed to process it into a composite bimetallic plate, and then performance testing is performed. First, the bimetallic plate is inspected, and defects of φ2mm equivalent or above are not allowed. It is also important to perform helium leak detection. Since the heat dissipation channel is arranged inside the composite heat sink and the divertor components are installed in the vacuum chamber, high vacuum sealing conditions must be met. Therefore, a heat sink sample is made with an internal wall thickness of 3mm, and according to the test requirements, 6.3MPa helium is passed at room temperature, and the leakage rate is ≤1.0×10 -10 Pa·m 3 / s; 5MPa helium gas at 300℃, leakage rate ≤1.0×10 -8 Pa·m 3 / s. In addition, mechanical strength tests are required and the interface bonding strength must be higher than 90% of the lower metal's own strength.

[0046] Step S2, after meeting the performance test standards, firstly process the bimetal plate according to the size specifications required by the composite heat sink. Then, using the electric spark or CNC processing technology, start from the CLF-1 steel side of the bimetal plate, and process the cooling channel with parallel fins inside it to improve the heat dissipation capacity.

[0047] Step S3, processing the cover plate 4 according to the required size, then drilling holes for the water inlet pipe 5 and the water outlet pipe 6 on the cover plate 4, and then using argon arc welding technology to weld the processed cover plate 4 to the surface of the heat sink CLF-1 steel to achieve sealing operation.

[0048] Step S4, preparing a tungsten-copper composite 1, first, casting molten oxygen-free copper onto the surface of pure tungsten, the casting temperature is slightly lower than the recrystallization temperature of tungsten, to form a preliminary composite structure; then, placing it in a vacuum hot pressing furnace, hot pressing treatment is performed in a vacuum environment, this step by applying pressure and temperature, and keeping the temperature and pressure for a certain period of time, so as to promote metallurgical bonding between oxygen-free copper and pure tungsten, forming a strong and uniform tungsten-copper composite material; then using a vacuum annealing process to treat it, in order to effectively eliminate the processing stress of Cu during the processing; finally, using a wire cutting process to process it into the required size of the tungsten-copper composite 1.

[0049] Step S5, after the composite heat sink surface is processed in step S3, a plurality of tungsten copper composite parts 1 prepared in step S4 are seamlessly welded to the ODS_Cu alloy surface of the heat sink by vacuum brazing. In particular, the brazing material is silver-free copper-tin-titanium brazing material, and the composition meets the requirements of the fusion reactor.

[0050] Step S6, finally, the water inlet pipe 5 and the water outlet pipe 6 are precisely welded to the pre-machined holes on the cover plate 4 by argon arc welding technology. At this point, the tungsten copper composite 1, the composite heat sink, the cover plate 4 and the water pipe are connected as a whole, that is, a complete divertor target plate module is obtained.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A flat-plate divertor module suitable for a magnetic confinement fusion reactor, characterized in that: It includes a composite heat sink and a plurality of tungsten-copper composite parts fixed on the surface of the composite heat sink; The composite heat sink comprises a copper alloy layer, a structural material layer, and a cover plate which are sequentially arranged in layers, and the tungsten-copper composite member is arranged on the surface of the copper alloy layer; A heat exchange cooling channel is provided between the copper alloy layer and the structural material layer; a water inlet pipe and a water outlet pipe are provided on the cover plate, and both the water inlet pipe and the water outlet pipe are connected to the heat exchange cooling channel; The tungsten-copper composite component is composed of a plasma-facing material layer and an oxygen-free copper intermediate layer, wherein the plasma-facing material layer is located on the outside; The plasma-facing material layer is pure tungsten with a thickness of 5 mm, and the oxygen-free copper intermediate layer is 0.5-1 mm thick; the copper alloy layer is made of alumina dispersion-strengthened copper material, the structural material layer is made of low-activated ferrite / martensitic steel, and the cover plate, water inlet pipe and water outlet pipe are all made of low-activated ferrite / martensitic steel.

2. The flat-plate divertor module suitable for a magnetic confinement fusion reactor according to claim 1, characterized in that: The copper alloy layer and the structural material layer are composited by using an explosion welding process.

3. The flat-plate divertor module suitable for a magnetic confinement fusion reactor according to claim 1, characterized in that: The plasma-facing material layer and the oxygen-free copper intermediate layer are connected by casting-assisted vacuum hot-pressing diffusion welding.

4. The flat-plate divertor module suitable for a magnetic confinement fusion reactor according to claim 1, characterized in that: The composite heat sink is connected to the tungsten-copper composite part by a vacuum brazing process, and the brazing material is a silver-free brazing material.

5. The flat-plate divertor module suitable for a magnetic confinement fusion reactor according to claim 1, characterized in that: The cooling channel is based on a super-evaporation heat exchange structure, and the copper alloy layer is provided with evenly distributed rectangular fin-shaped inner fins; the cooling channel is filled with coolant, which can remove 20MW / m 2 of heat flow.

6. A method for preparing a flat-plate divertor module suitable for a magnetic confinement fusion reactor as claimed in any one of claims 1 to 5, characterized in that: The steps include: S1. Based on the size requirements of the divertor, an alumina dispersion-strengthened copper alloy metal plate and a low-activated ferrite / martensitic steel metal plate are placed in parallel and processed into a composite bimetallic composite plate by an explosion welding process; then the performance of the composite plate is tested; S2. After the composite plate performance test meets the requirements, a cooling channel with parallel inner fins is machined on the composite plate by electric spark or machining; S3. Pre-open holes on the cover plate for installing the water inlet pipe and the water outlet pipe, and use argon arc welding technology to cover the cover plate on the composite plate for sealing; S4, casting the molten oxygen-free copper onto the surface of pure tungsten, and then vacuum hot pressing it in a vacuum hot pressing furnace, and then machining it into the required size of the tungsten-copper composite part; S5, after the composite heat sink surface processed in step S3, a plurality of tungsten-copper composite parts prepared in step S4 are seamlessly welded to the surface of the alumina dispersion-strengthened copper alloy metal plate of the heat sink by vacuum brazing; S6. Finally, the water inlet pipe and the water outlet pipe are connected to the reserved hole positions on the cover plate by using argon arc welding process, so as to obtain a complete divertor target plate module.

7. The preparation method according to claim 6, characterized in that: The composite plate prepared in step S1 is subjected to interface nondestructive testing and helium leakage testing.

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