A method for preparing a tungsten-copper composite metal component for a nuclear fusion device, a tungsten matrix, and the tungsten-copper composite metal component.

Abstract

This invention relates to a tungsten-copper composite metal component for nuclear fusion devices, a method for preparing a tungsten matrix, and a method for preparing the tungsten-copper composite metal component, belonging to the field of materials technology for nuclear fusion. The method includes: firstly, designing a tungsten entity and its surface tungsten grid layer structure through three-dimensional modeling, and then importing it into an electron beam powder bed melting (EBM) device; under high vacuum and preheating conditions of 950~1500℃, using an electron beam to melt tungsten powder to integrally print a high-density tungsten matrix; then, under controlled thermo-mechanical conditions, using processes such as melt infiltration, spraying, or vapor deposition to composite copper or copper alloys into the tungsten grid layer, forming an embedded connection structure. This process utilizes EBM to achieve net-shape forming of complex tungsten structures and alleviates the thermal mismatch stress of tungsten and copper through gridded interface design, significantly improving the thermal fatigue resistance and interface stability of the component under high temperature and high heat load, and is suitable for key components such as the first wall and divertor of nuclear fusion devices.

Description

Technical Field

[0001] This invention relates to a tungsten-copper composite metal component for a nuclear fusion device, a method for preparing a tungsten matrix, and a method for preparing the tungsten-copper composite metal component. It belongs to the field of materials technology for nuclear fusion, and more specifically to the field of materials technology for the first wall and divertor of a nuclear fusion device. Background Technology

[0002] Nuclear fusion energy is considered an important technological direction for achieving large-scale, clean, safe, and sustainable energy supply. With global investment in basic research and engineering verification capabilities in the field of nuclear fusion, related technologies have gradually progressed from the physical experiment stage to the engineering, device-based, and long-term stable operation stages.

[0003] Nuclear fusion has been explicitly identified as a key development direction for future energy systems and major scientific facilities, placing high demands on the reliability, lifespan, and manufacturability of critical materials and structural components for nuclear fusion devices under extreme operating conditions. This field is also a battleground for key technologies.

[0004] However, existing first-wall / divertor components used in nuclear fusion devices suffer from the following problems under high heat load, strong neutron irradiation, and complex thermo-radiation coupling environments: 1) "Structural interfacial stress" caused by thermal expansion mismatch: Tungsten and copper or copper alloys have large differences in their coefficients of thermal expansion. During thermal cycling, their corresponding expansions are inconsistent. Under interfacial constraints, this difference in expansion transforms into a composite stress dominated by shear, which forms stress concentrations in pores and other areas, inducing thermal fatigue damage. The thermal damage mechanism is as follows: high shear stress at the interface during thermal cycling → microcracks → debonding → increased thermal resistance → local overheating → accelerated failure. The interfacial microcracks gradually expand and lead to debonding / delamination, reducing the effective contact area and increasing the interfacial thermal resistance, thus forming hot spots. These hot spots amplify thermal mismatch and local softening, forming a positive feedback chain of "damage → overheating → re-damage". This contradiction, driven by the inherent differences in materials, is difficult to completely eliminate and can only be alleviated at the structural and material system level; 2) Manufacturing costs and repair / replacement: HIP process has a long cycle and high furnace usage, and is sensitive to parameters such as vacuum degree, temperature and pressure curve, and temperature uniformity, resulting in large yield fluctuations. Once internal defects or interface non-bonding occur, it is difficult to rework, and the total cost of scrapping a single part is relatively large; Traditional processing methods face high processing difficulty when dealing with complex and curved structure design requirements, and at the same time limit the flexibility of design; If the direction of cracks generated at the joint surface of rolled composite materials is perpendicular to the heat conduction direction, it is equivalent to forming a barrier during heat transfer, which will significantly increase the interfacial thermal resistance and easily lead to heat accumulation; Under thermal cycling or high heat flux conditions, crack propagation is easily accelerated, causing component failure.

[0005] Therefore, there is an urgent need for a new tungsten-copper composite material and / or corresponding component structure and preparation method to overcome the above-mentioned defects. Summary of the Invention

[0006] To address the aforementioned problems, in a first aspect, the present invention provides a tungsten-copper composite metal component for nuclear fusion devices.

[0007] The technical solution is as follows:

[0008] A tungsten-copper composite metal component for a nuclear fusion device, the component comprising a tungsten substrate and a copper-containing layer fixed to the surface of the tungsten substrate; the tungsten substrate comprising a tungsten solid and a tungsten grid layer integrally connected thereto; the copper-containing layer comprising a continuous copper-containing metal layer and a copper-containing metal connecting layer integrally connected thereto; the copper-containing metal connecting layer having a structure matching the tungsten grid layer, such that the copper-containing layer is embeddedly connected to the tungsten substrate.

[0009] In the above technical solution of the present invention, the material of the tungsten matrix includes pure tungsten metal and tungsten-based alloy. The tungsten-based alloy can be a nickel-tungsten alloy with a tungsten content exceeding the nickel content, and small amounts of elements such as tantalum, niobium, and copper can also be added to the nickel-tungsten alloy.

[0010] This invention provides a novel tungsten-copper composite metal component suitable for the first wall / divertor components of nuclear fusion devices (such as tokamaks and stellarators). This invention is not a simple improvement on traditional processes, but rather a fundamental solution integrating structural design, material preparation, and composite processing, based on a profound understanding of material failure mechanisms under extreme nuclear fusion conditions (high heat flux, strong neutron irradiation, high-energy particle bombardment, and thermomechanical fatigue). Its goal is to solve core engineering problems of traditional tungsten-copper composite materials, such as interface failure due to thermal expansion mismatch, insufficient ability to manufacture complex structures, high processing costs, and low yield, thereby providing crucial materials and components for the long-life, high-reliability operation of future fusion reactors.

[0011] Background technology has clearly indicated that the combination of tungsten (high melting point, low sputtering rate, high heat load capacity) and copper (high thermal conductivity, excellent mechanical and processing properties) is an ideal choice for plasma components (PFCs). However, the difference in the coefficients of thermal expansion between tungsten and copper is the root cause of interfacial stress concentration, crack initiation and propagation, and ultimately, component delamination failure under thermal cycling.

[0012] This invention is a systematic solution to the aforementioned contradictions. It transforms the manufacturing of plasma components from a process of "post-material bonding and processing" into a digital and integrated process of "structural design first, material growth and composite on demand".

[0013] Firstly, structural innovation. The core structural innovation of this invention lies in the introduction of an integrally formed tungsten mesh layer between the tungsten substrate and the copper-containing layer. This layer is not simply a roughened surface, but a three-dimensional continuous structure with specific porosity and topological shape (such as TPMS lattice, beam-bar lattice). The technical logic is to replace the traditional two-dimensional planar metallurgical bonding with "three-dimensional interlocking mechanical anchoring." When copper or copper alloy fills and encapsulates this mesh through subsequent composite processes, the two form an embedded connection in three-dimensional space. Its direct technical effects are: 1) Stress buffering and redistribution: The mesh structure disperses the high shear stress originally concentrated at the two-dimensional interface to the various rod nodes of the three-dimensional mesh, and absorbs part of the strain energy through the elastic deformation of the rods, greatly alleviating stress concentration; 2) Increasing the effective bonding area: The three-dimensional mesh interface makes the actual bonding area of ​​tungsten and copper far greater than that of the planar interface by several times or even tens of times, significantly reducing the heat flux density and mechanical load per unit area, and improving the load-bearing and heat transfer capacity of the interface; 3) Suppressing crack propagation: When cracks propagate to the mesh structure, their paths are disrupted, branched, or even terminated by the complex three-dimensional network, making it difficult to form large through cracks. The "porosity gradient" design in the preferred scheme further realizes the smooth transition of material properties (such as modulus and thermal conductivity) from the tungsten side to the copper side, fundamentally optimizing the thermo-mechanical matching.

[0014] Secondly, manufacturing innovation. The preparation method of this invention creatively integrates two processes: "electron beam bed fusion (EBM)" and "controlled subsequent composite processes (melting / spraying / vapor deposition)". Its technical logic lies in utilizing the unique advantages of EBM technology in refractory metal processing to prepare highly dense and structurally precise tungsten mesh preforms that are impossible to achieve with traditional methods for subsequent composite processes. The high vacuum environment and powder bed preheating of 950~1500℃ in the EBM process bring dual core effects: 1) Extremely low impurity and oxygen content: The high vacuum environment greatly inhibits the oxidation and contamination of tungsten at high temperatures, which is key to obtaining high-purity, high-ductility tungsten matrix and is crucial for its stable performance under irradiation; 2) Extremely low thermal stress and high density: High-temperature preheating makes the printing process approximate a "hot isostatic pressing" state, where the powder is pre-sintered before melting, significantly reducing the temperature gradient and thermal stress during molten pool solidification, thus enabling the direct printing of highly dense, crack-free tungsten entities and fine meshes. Building upon this foundation, copper / copper alloys are composited using controlled processes such as melt infiltration, spraying, or vapor deposition, achieving a perfect combination of "digital customization of tungsten skeleton" and "precise and controllable copper filling."

[0015] Thirdly, there is a comprehensive improvement in performance and efficiency.

[0016] Breakthrough Enhancement in Service Stability and Lifespan: Through the aforementioned structural and process innovations, the components of this invention fundamentally improve the thermomechanical fatigue performance of the tungsten-copper interface. Embedded connections significantly enhance resistance to delamination, and optimized thermo-mechanical matching reduces damage accumulation under thermal cycling. The direct technical effect is that the thermal cycling life of the component under simulated fusion heat loads is expected to be an order of magnitude longer than that of traditional flat-interface components, significantly improving the operational reliability and maintenance cycle of fusion devices.

[0017] The realization of design freedom and functional customization: EBM technology makes it possible to manufacture lightweight structures with complex curved surfaces, internal channels, and lattice filling. Combined with gradient mesh design, it is possible to achieve the on-demand distribution of thermal conductivity, strength, and shock resistance in different regions of components, perfectly adapting to the complex first wall / divertor geometry and non-uniform heat load distribution in future fusion reactors.

[0018] Fundamental optimization of efficiency and cost across the entire process: Integrated printing of tungsten solids and meshes eliminates multiple steps such as tungsten skeleton preparation, machining, and assembly in traditional methods; EBM technology has a high powder utilization rate (>95%), and unmelted powder can be recycled, greatly reducing the loss of expensive tungsten materials; EBM process has high stability, and the printed tungsten matrix is ​​a completely dense part, resulting in a high success rate for subsequent composite processes (such as melt infiltration); For local damage, theoretically, the same process can be used for repair, reducing the cost of replacing the entire component.

[0019] As a preferred embodiment of the above technical solution, the tungsten mesh layer includes, but is not limited to, TPMS lattice structure, beam-bar lattice structure, and honeycomb structure.

[0020] The TPMS (Triple Period Minimal Surface) structure boasts an extremely high specific surface area and excellent mechanical properties, maximizing interfacial bonding area and stress dispersion. The beam-rod lattice structure offers flexible design and facilitates anisotropic control. The honeycomb structure exhibits outstanding in-plane mechanical and thermal performance. Multiple structural options are available, enabling customized optimization for different service locations (such as the first wall plasma region or the divertor target plate region).

[0021] As a preferred embodiment of the above technical solution, the copper-containing layer is a pure copper layer or a copper alloy layer with a copper content of not less than 50 mol%.

[0022] As a preferred embodiment of the above technical solution, the copper alloy includes, but is not limited to, chromium-zirconium copper, copper-hafnium alloy, ODS copper, and diamond copper alloy.

[0023] Pure copper offers excellent thermal conductivity. Copper alloys (such as chromium-zirconium copper) significantly improve strength and recrystallization temperature while maintaining good thermal conductivity. ODS copper (oxide dispersion strengthened copper) and diamond copper composites can greatly enhance high-temperature strength, resistance to radiation swelling, and resistance to thermal fatigue. This flexibility in material selection allows components to withstand both high heat flux shocks and strong neutron radiation environments, resulting in overall performance far exceeding that of traditional CuCrZr alloys.

[0024] As a preferred embodiment of the above technical solution, in the embedded connection structure between the copper-containing layer and the tungsten substrate, the tungsten content gradually decreases from 100% to zero from the tungsten solid side to the copper-containing layer side.

[0025] This gradient design achieves a continuous and smooth transition of the material's thermophysical properties (such as coefficient of thermal expansion and elastic modulus) from the high-melting-point, high-modulus tungsten side to the high-thermal-conductivity, low-modulus copper side. This gradient layer can most effectively buffer thermal mismatch strain and minimize interfacial stress, making it one of the ultimate structural solutions for solving thermal stress problems.

[0026] Secondly, the present invention provides a method for preparing the above-mentioned tungsten matrix.

[0027] The technical solution is as follows:

[0028] The above-mentioned method for preparing the tungsten matrix includes the following steps:

[0029] S1. Use 3D modeling software to design the model of tungsten solid and tungsten mesh layer, slice the designed model, and import it into the printing equipment;

[0030] S2. Set the equipment printing parameters: beam spot size range 20~1000μm, power 200W~8000W, layer thickness 10~300μm, preheating temperature 950~1500℃;

[0031] S3. Add tungsten powder to the powder hopper and the construction hopper. The powder should have a particle size between 5 and 200 μm.

[0032] S4. An electron beam controlled by an induction coil melts the powder in the vacuum processing chamber, prints the workpiece, and obtains a tungsten matrix including a tungsten solid and a tungsten mesh layer integrally connected thereto.

[0033] As a preferred embodiment of the above technical solution, the following steps are also included:

[0034] S5. After printing is complete, remove the tungsten substrate print with grid and clean the powder.

[0035] Thirdly, the present invention provides a method for preparing the above-mentioned tungsten-copper composite metal component.

[0036] The technical solution is as follows:

[0037] A method for preparing tungsten-copper composite metal components includes the following steps:

[0038] S1. Use 3D modeling software to design the model of tungsten solid and tungsten mesh layer, slice the designed model, and import it into the printing equipment;

[0039] S2. Set the equipment printing parameters: beam spot size range 20~1000μm, power 200W~8000W, layer thickness 10~300μm, preheating temperature 950~1500℃;

[0040] S3. Add tungsten powder to the powder hopper and the construction hopper. The powder should have a particle size between 5 and 200 μm.

[0041] S4. An electron beam controlled by an induction coil melts the powder in the vacuum processing chamber, prints the workpiece, and obtains a tungsten matrix including a tungsten solid and a tungsten mesh layer integrally connected thereto.

[0042] S5. Under controlled thermo-mechanical conditions, the tungsten grid layer and the copper-containing layer are composited to obtain the corresponding tungsten-copper composite metal component.

[0043] As a preferred embodiment of the above technical solution, the tungsten mesh layer and the copper-containing layer are composited under controlled thermo-mechanical conditions. Specifically, the raw material of the copper-containing layer is infiltrated into the tungsten mesh layer under vacuum or protective atmosphere pressure melting and infiltration, thereby forming a copper-containing metal connecting layer and a copper-containing metal continuous layer integrally connected thereto.

[0044] As a preferred embodiment of the above technical solution, the tungsten mesh layer and the copper-containing layer are composited under controlled thermo-mechanical conditions. Specifically, a plasma spraying method is used to spray the raw material of the copper-containing layer into the tungsten mesh layer in a plasma state and cover the tungsten mesh layer, forming a copper-containing metal connecting layer and a copper-containing metal continuous layer integrally connected thereto.

[0045] As a preferred embodiment of the above technical solution, the tungsten grid layer and the copper-containing layer are composited under controlled thermo-mechanical conditions. Specifically, the copper-containing raw material is gradually deposited into the tungsten grid layer and covered by the tungsten grid layer using a vapor phase physical deposition method to form a copper-containing metal bonding layer and an integrally connected copper-containing metal continuous layer.

[0046] Melt infiltration is a mature process that can produce highly dense, high thermally conductive copper substrates, suitable for large-volume components with high thermal conductivity requirements. Plasma spraying offers fast deposition rates, can produce thick coatings, and allows for parameter adjustments to achieve coatings with specific properties, making it suitable for surface strengthening or rapid manufacturing. Vapor phase physical deposition (e.g., electron beam physical vapor deposition, EB-PVD) can achieve atomic-layer-by-layer deposition at relatively low temperatures, producing pure, highly cohesive interfaces and perfectly replicating complex mesh morphologies, making it particularly suitable for precision components with extremely high requirements for interface quality and thermal damage control.

[0047] In summary, the present invention has the following beneficial effects:

[0048] 1. By using the tungsten grid layer embedded connection structure, the problem of interface failure caused by tungsten-copper thermal mismatch is fundamentally solved. Combined with the high-purity and high-density tungsten matrix prepared by EBM, the components exhibit excellent thermal fatigue resistance, interface stability and structural integrity when subjected to extreme conditions such as high heat flux, strong thermal shock and neutron irradiation, providing key material guarantee for the long-term safe operation of fusion devices.

[0049] 2. The combination of EBM additive manufacturing and controlled composite processes has enabled the integrated near-net-shape forming of complex curved surfaces, internal channels, and gradient functional structures. This not only greatly simplifies the manufacturing process and reduces the processing difficulty and cost of complex components, but also liberates component design from the constraints of "manufacturing feasibility," truly realizing "design-driven performance" and opening up new possibilities for the optimized design of future fusion reactors.

[0050] 3. From the high yield rate brought about by high material utilization and high process stability, to the possibility of partial component repair, this solution significantly reduces the manufacturing and maintenance costs of plasma components, which are the "core consumables of fusion reactors". Its digital and flexible manufacturing characteristics are also very suitable for the rapid iteration and customized production needs of small batches and multiple varieties of fusion reactor components.

[0051] 4. This invention constructs a complete technical system from innovative structural design to advanced additive manufacturing and various controllable composite processes; it not only provides feasible solutions to current engineering problems, but its core ideas of "structural-functional integration", "material gradient" and "digital manufacturing" also represent the development direction of composite material components for nuclear fusion and other extreme environments in the future, and have high technical foresight and industrial leading value.

[0052] 5. In summary, the tungsten-copper composite metal component and its preparation method of the present invention represent a systematic innovation in the material system and manufacturing technology of plasma-oriented components for nuclear fusion. Starting from the failure mechanism, it successfully reconciles the contradictions between tungsten and copper, the best pairing, through the innovative ideas of "trading performance for structure" and "achieving structure through process". It provides a complete solution from theoretical basis, structural design to engineering implementation for key components of fusion reactors with high performance, high reliability and long life, which is of great strategic significance for promoting the early realization of controlled nuclear fusion energy. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the tungsten-copper composite metal component of the present invention;

[0054] Figure 2 This is a schematic diagram of the tungsten matrix in Example 1;

[0055] Figure 3 Metallographic image of the tungsten substrate in Example 1;

[0056] Figure 4 This is a photograph of the tungsten substrate from Example 1.

[0057] Figure 5 This is a schematic diagram of the tungsten matrix structure in Example 2;

[0058] Figure 6 Metallographic image of the tungsten substrate in Example 2;

[0059] Figure 7 This is a physical image of the tungsten substrate in Example 2. Detailed Implementation

[0060] The present invention will be further explained and described below with reference to the accompanying drawings.

[0061] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. Any changes made by those skilled in the art after reading this specification, as long as they fall within the scope of the claims, will be protected by patent law.

[0062] Example 1

[0063] This embodiment provides a tungsten-copper composite metal component for a nuclear fusion device and its preparation method, which is implemented according to the following steps:

[0064] Step 1: Design the structure using modeling software. The solid part measures 52mm (length) × 14mm (width) × 2.5mm (height), and the upper mesh structure measures 50mm (length) × 12mm (width) × 5mm (height). The mesh is a Gyroid lattice structure. Adjust the mesh structure to change the volume of copper infiltration / copper alloy, such as... Figure 1 and Figure 2As shown, from the tungsten side to the copper side, the tungsten content gradually transitions from 100% to 0%; Figure 1 This is a schematic diagram of the structure of a tungsten-copper composite metal component; Figure 2 This is a schematic diagram of the tungsten substrate structure in this embodiment;

[0065] Step 2: The solid and mesh structure is integrally formed using an electron beam printer. The specific process is as follows:

[0066] Step 2.1: Slice the 3D model of the tungsten component to generate multi-layer slice data; the scanning area can be divided into contour area, thin-walled / fine channel area and main filling area according to the geometric features of the slices, and electron beam process parameters can be set separately or in conjunction; the parameters include, but are not limited to:

[0067] The preferred construction environment vacuum level is below 10. -4 mbar;

[0068] Beam spot size is approximately 20~1000 μm;

[0069] The electron beam power is approximately 200~8000W;

[0070] The layer thickness is approximately 10~300μm;

[0071] The preheating temperature of the powder bed is approximately 1000~1400℃;

[0072] Electron beam scanning has the following parameter coupling combinations;

[0073] Scanning on a powder bed considers factors such as the number of contour tracks, scanning strategy, interlayer rotation angle, vector length limit, focus / defocus amount, jump / dwell delay, and number of repeated scans. These parameters are coupled and optimized to control the molten pool geometry and interlayer metallurgical bonding, and can be dynamically adjusted layer-by-layer / region-by-region according to the contour complexity, fill rate, wall thickness, and channel characteristics of the lamination.

[0074] Discrete point energy input can also be performed using a powder bed for local pre-consolidation / preheating, energy compensation for small features, and reinforcement of thin walls or channel boundaries. The scanning parameters include, but are not limited to: spot size (or focal point / defocus), spot power (or beam current / accelerating voltage combination), residence time (or pulse width), spot spacing and lattice arrangement, number of spot repetitions, inter-spot delay / jump delay, scanning sequence and partitioning strategy, etc., and are set in conjunction with slice thickness and powder bed preheating temperature. These scanning parameters are coupled and optimized, with core constraints including the linkage between single-point energy packets and the spatiotemporal distribution between points, and can be dynamically adjusted layer-by-layer / region-by-region based on slice geometry.

[0075] Through the above-mentioned scope and coupling, tungsten powder can be fully melted and stably shaped in a vacuum environment to obtain a high-density tungsten structure and significantly reduce macroscopic cracks and incomplete fusion defects, which is suitable for additive manufacturing of high-performance tungsten-based components;

[0076] Step 2.2: Place tungsten powder in the powder hopper and build chamber of the equipment. The powder particle size should be between 5 and 200 μm. Melt the powder in the vacuum processing chamber using an electron beam controlled by an induction coil to print the workpiece.

[0077] Step 3: After printing, remove the printed part with the grid and clean the powder; the tungsten substrate is as follows. Figure 4 As shown; metallographic analysis was performed on the tungsten matrix sample of this embodiment, as follows. Figure 3 As shown, the solid tungsten portion is dense and crack-free; from the tungsten side to the copper side, the tungsten content gradually transitions from 100% to 0%, and the copper is evenly distributed and tightly bonded to the tungsten mesh structure.

[0078] Step 4: Copper infiltration is performed on the printed part at a temperature of 1100~1200℃. The copper is infiltrated into the pores of the grid structure by using a protective atmosphere pressurized infiltration method (such as holding at 1MPa argon pressure for 2 hours) to prepare a tungsten-copper composite metal component.

[0079] Example 2

[0080] This embodiment provides a tungsten-copper composite metal component for a nuclear fusion device and its preparation method, which is implemented according to the following steps:

[0081] Step 1: Design the structure using modeling software. The solid part measures 52mm (length) × 14mm (width) × 2.5mm (height), and the upper mesh structure measures 50mm (length) × 12mm (width) × 5mm (height). The mesh is a Diamond lattice structure. Adjust the mesh structure to change the volume of copper infiltration / copper alloy, such as... Figure 1 and Figure 5 As shown, from the tungsten side to the copper side, the tungsten content gradually transitions from 100% to 0%; Figure 1 This is a schematic diagram of the structure of a tungsten-copper composite metal component; Figure 5 This is a schematic diagram of the tungsten substrate structure in this embodiment;

[0082] Step 2: The solid and mesh structures are fabricated in one piece using an electron beam printer. The specific process is as follows:

[0083] Step 2.1: Slice the 3D model of the tungsten component to generate multi-layer slice data; the scanning area can be divided into contour area, thin-walled / fine channel area and main filling area according to the geometric features of the slices, and electron beam process parameters can be set separately or in conjunction; the parameters include, but are not limited to:

[0084] The preferred construction environment vacuum level is below 10.-4 mbar;

[0085] Beam spot size is approximately 20~1000 μm;

[0086] The electron beam power is approximately 200~8000W;

[0087] The layer thickness is approximately 10~300μm;

[0088] The preheating temperature of the powder bed is approximately 1000~1400℃;

[0089] Electron beam scanning has the following parameter coupling combinations;

[0090] Scanning on a powder bed considers factors such as the number of contour tracks, scanning strategy, interlayer rotation angle, vector length limit, focus / defocus amount, jump / dwell delay, and number of repeated scans. These parameters are coupled and optimized to control the molten pool geometry and interlayer metallurgical bonding, and can be dynamically adjusted layer-by-layer / region-by-region according to the contour complexity, fill rate, wall thickness, and channel characteristics of the lamination.

[0091] Discrete point energy input can also be performed using a powder bed for local pre-consolidation / preheating, energy compensation for small features, and reinforcement of thin walls or channel boundaries. The scanning parameters include, but are not limited to: spot size (or focal point / defocus), spot power (or beam current / accelerating voltage combination), residence time (or pulse width), spot spacing and lattice arrangement, number of spot repetitions, inter-spot delay / jump delay, scanning sequence and partitioning strategy, etc., and are set in conjunction with slice thickness and powder bed preheating temperature. These scanning parameters are coupled and optimized, with core constraints including the linkage between single-point energy packets and the spatiotemporal distribution between points, and can be dynamically adjusted layer-by-layer / region-by-region based on slice geometry.

[0092] Through the above-mentioned scope and coupling, tungsten powder can be fully melted and stably shaped in a vacuum environment to obtain a high-density tungsten structure and significantly reduce macroscopic cracks and incomplete fusion defects, which is suitable for additive manufacturing of high-performance tungsten-based components;

[0093] Step 2.2: Place tungsten powder in the powder hopper and build chamber of the equipment. The powder particle size should be between 5 and 200 μm. Melt the powder in the vacuum processing chamber using an electron beam controlled by an induction coil to print the workpiece.

[0094] Step 3: After printing, remove the printed part with the grid and clean the powder; the tungsten substrate is as follows. Figure 7 As shown; metallographic analysis was performed on the tungsten matrix sample of this embodiment, as follows. Figure 6 As shown, the solid tungsten portion is dense and crack-free; from the tungsten side to the copper side, the tungsten content gradually transitions from 100% to 0%, and the copper is evenly distributed and tightly bonded to the tungsten mesh structure.

[0095] Step 4: Copper infiltration is performed on the printed part. The infiltration temperature is controlled at 1100~1200℃. The copper is infiltrated into the pores of the grid structure by using a protective atmosphere pressurized infiltration method (such as holding at 1MPa argon pressure for 2 hours) to prepare the tungsten copper composite metal component.

Claims

1. A tungsten-copper composite metal component for a nuclear fusion device, characterized in that, The component includes a tungsten substrate and a copper-containing layer fixed to the surface of the tungsten substrate; the tungsten substrate includes a tungsten solid and a tungsten mesh layer integrally connected thereto; the copper-containing layer includes a continuous copper metal layer and a copper metal connecting layer integrally connected thereto; the copper metal connecting layer has a structure that matches the tungsten mesh layer, so that the copper-containing layer is embeddedly connected to the tungsten substrate.

2. The tungsten-copper composite metal component for a nuclear fusion device according to claim 1, characterized in that, The tungsten mesh layer's mesh structure includes, but is not limited to, TPMS lattice structure, beam-and-rod lattice structure, and honeycomb structure.

3. A tungsten-copper composite metal component for a nuclear fusion device according to claim 1, characterized in that, The copper-containing layer is a pure copper layer or a copper alloy layer with a copper content of not less than 50 mol%.

4. A tungsten-copper composite metal component for a nuclear fusion device according to claim 3, characterized in that, The copper alloys include, but are not limited to, chromium-zirconium copper, copper-hafnium alloy, ODS copper, and diamond copper alloy.

5. A tungsten-copper composite metal component for a nuclear fusion device according to claim 3, characterized in that, In the embedded connection structure between the copper-containing layer and the tungsten substrate, the tungsten content gradually decreases from 100% to zero from the tungsten solid side to the copper-containing layer side.

6. A method for preparing a tungsten matrix as described in any one of claims 1 to 5, comprising the following steps: S1. Use 3D modeling software to design the model of tungsten solid and tungsten mesh layer, slice the designed model, and import it into the printing equipment; S2. Set the equipment printing parameters: beam spot size range 20~1000μm, power 200W~8000W, layer thickness 10~300μm, preheating temperature 950~1500℃; S3. Add tungsten powder to the powder hopper and the construction hopper. The powder should have a particle size between 5 and 200 μm. S4. An electron beam controlled by an induction coil melts the powder in the vacuum processing chamber, prints the workpiece, and obtains a tungsten matrix including a tungsten solid and a tungsten mesh layer integrally connected thereto.

7. A method for preparing a tungsten-copper composite metal component as described in any one of claims 1 to 5, comprising the following steps: S1. Use 3D modeling software to design the model of tungsten solid and tungsten mesh layer, slice the designed model, and import it into the printing equipment; S2. Set the equipment printing parameters: beam spot size range 20~1000μm, power 200W~8000W, layer thickness 10~300μm, preheating temperature 950~1500℃; S3. Add tungsten powder to the powder hopper and the construction hopper. The powder should have a particle size between 5 and 200 μm. S4. An electron beam controlled by an induction coil melts the powder in the vacuum processing chamber, prints the workpiece, and obtains a tungsten matrix including a tungsten solid and a tungsten mesh layer integrally connected thereto. S5. Under controlled thermo-mechanical conditions, the tungsten grid layer and the copper-containing layer are composited to obtain the corresponding tungsten-copper composite metal component.

8. The method according to claim 7, characterized in that, The composite of the tungsten mesh layer and the copper-containing layer is carried out under controlled thermo-mechanical conditions. Specifically, the raw material of the copper-containing layer is infiltrated into the tungsten mesh layer under vacuum or protective atmosphere pressure melting and infiltration, thereby forming a copper-containing metal connecting layer and an integrally connected copper-containing metal continuous layer.

9. The method according to claim 7, characterized in that, The composite of tungsten mesh layer and copper-containing layer is carried out under controlled thermo-mechanical conditions. Specifically, the raw material of copper-containing layer is sprayed into the tungsten mesh layer in a plasma state and covered by the tungsten mesh layer to form a copper-containing metal bonding layer and an integrally connected copper-containing metal continuous layer.

10. The method according to claim 7, characterized in that, The composite of tungsten mesh layer and copper-containing layer is carried out under controlled thermo-mechanical conditions. Specifically, the raw material of copper-containing layer is gradually deposited in tungsten mesh layer and covered by tungsten mesh layer using vapor phase physical deposition method to form copper-containing metal bonding layer and copper-containing metal continuous layer integrally connected thereto.

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