Tungsten-copper composite module and preparation method and application thereof

Abstract

The invention belongs to the technical field of tungsten-copper composite module preparation, and particularly relates to a tungsten-copper composite module and a preparation method and application thereof. The tungsten-copper composite module comprises a tungsten block and a copper cooling runner in the tungsten block; a copper layer and a W-Cu continuous diffusion layer are arranged from the inner wall of the copper cooling flow channel to the outside. The tungsten-copper composite module contains the W-Cu continuous diffusion layer, so that metallurgical interface bonding is formed between copper and tungsten, and the interface bonding strength is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of tungsten-copper composite module preparation, and particularly relates to a tungsten-copper composite module and a preparation method and application thereof. BACKGROUND

[0002] In a magnetic confinement nuclear fusion device, a divertor tungsten-copper composite module directly faces a high-temperature plasma of tens of millions of degrees, and the performance thereof determines the service life of the device. The current mainstream technology has three technical bottlenecks. First, a fusion hot pressing method needs to melt copper at a high temperature (such as 1180℃) in a hydrogen atmosphere and then coat the copper on the surface of tungsten. Such a method not only has high energy consumption (the hydrogen consumption of a single piece is generally >5m 3 ), but also easily causes the molten copper liquid to be oxidized to form interface pores, thereby reducing the thermal conductivity. Moreover, the fusion process needs to be carried out on each module separately in a furnace, and the size of the fusion mold limits the processing capacity (generally ≤5 pieces at a time).

[0003] The common defects of the above processes are that multi-step operations introduce interface pollution risks, and high-cost equipment restricts industrial application. A single divertor of a fusion device needs more than 5000 modules, and the production cost of the above processes accounts for a high proportion. Therefore, it is urgent to develop a manufacturing method with simplified process, controllable cost and interface toughening. SUMMARY

[0004] To solve the above problems, the application provides a tungsten-copper composite module and a preparation method and application thereof. The preparation method realizes atomic-level diffusion bonding of tungsten and copper in a single process through the synergistic effect of precise gap cooperation of a copper column and a tungsten plate and hot isostatic pressing plastic deformation.

[0005] The application is implemented by the following technical solutions: In a first aspect, the application provides a tungsten-copper composite module, which comprises a tungsten block and a copper cooling channel in the tungsten block; and from the inner wall of the copper cooling channel outward, comprises a copper layer and a W-Cu continuous diffusion layer.

[0006] In some possible implementation manners, the thickness of the copper layer is 1.0mm-2.0mm.

[0007] In some possible implementation manners, the thickness of the diffusion layer is 1μm-5μm.

[0008] In some possible implementation manners, the inner diameter of the copper cooling channel is 15mm-18mm.

[0009] In a second aspect, the present application provides a method for preparing a tungsten-copper composite module, comprising the following steps: After the tungsten plate with copper columns embedded is encapsulated, the tungsten-copper composite module is obtained by hot isostatic pressing and deep hole drilling processing. The deep hole drilling processing step comprises hollowing the center of the tungsten-copper composite module after hot isostatic pressing to obtain the copper cooling flow channel.

[0010] In some possible implementations, in the hot isostatic pressing, the hot isostatic pressing temperature is 950-1050°C.

[0011] In some possible implementations, in the hot isostatic pressing, the isostatic pressure is 100-150 MPa.

[0012] In some possible implementations, the hot isostatic pressing step comprises: After the temperature is raised to the hot isostatic pressing temperature at a rate of 2-10°C / min in an inert atmosphere, the isostatic pressure is applied and the temperature is kept constant, and finally cooled to below 200°C.

[0013] In some possible implementations, the preparation of the tungsten plate with copper columns embedded comprises the following steps: After drilling a plurality of through holes in the tungsten plate, a plurality of copper columns are embedded in the plurality of through holes; The difference between the diameter of the through hole and the diameter of the copper column is 0.05-0.10 mm.

[0014] In some possible implementations, the difference between the height of the copper column and the thickness of the tungsten plate is 0.5-3.0 mm.

[0015] In some possible implementations, the diameter of the through hole is 15-18 mm.

[0016] In some possible implementations, the distance between the centers of adjacent through holes is 25-29 mm.

[0017] In some possible implementations, the thickness of the tungsten plate is 14-16 mm.

[0018] In some possible implementations, the encapsulation comprises the following steps: The tungsten plate with copper columns is placed in an encapsulation assembly, and the vacuum is extracted to 5×10 -3 Pa or more.

[0019] In some possible implementations, in the encapsulation, the temperature during vacuum extraction is 290-310°C.

[0020] In a third aspect, the application provides a tungsten-copper composite module for use in a divertor.

[0021] The tungsten-copper composite module and the preparation method thereof provided by the application have at least the following beneficial technical effects compared with the prior art: (1) The tungsten-copper composite module contains a W-Cu continuous diffusion layer, which forms a metallurgical interface between copper and tungsten and improves the interface bonding strength.

[0022] (2) The preparation method of the tungsten-copper composite module embeds a copper column in a tungsten plate through hole, and then realizes metallurgical bonding of tungsten and copper by single hot isostatic pressing. This avoids the technical problems of existing molten copper liquid processing, such as reduction of module thermal conductivity and lattice distortion in the heat affected zone caused by high-energy beam welding, realizes high-reliability tungsten-copper interface connection, and meets the extreme thermal load bearing requirements of the divertor module of the nuclear fusion device.

[0023] (3) The preparation method of the tungsten-copper composite module is simple, and eliminates the need for a cladding furnace, an electron beam welding machine, and a coating device; the cycle is short, the single-piece production cycle is shortened to less than 24 hours (60% less than the traditional process), the energy consumption is reduced by 70%, and the product qualification rate is greater than 99%. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments or the prior art, the drawings needed in the following embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the drawings, and other drawings can be obtained by those skilled in the art without creative labor.

[0025] Figure 1 A structure schematic diagram of a tungsten-copper composite module provided by the embodiment of the application; Figure 2 In the preparation method of the tungsten-copper composite module provided by the embodiment of the application, a structure schematic diagram of a copper column embedded in a tungsten plate; Figure 3 A SEMS diagram of a W-Cu continuous diffusion layer of a tungsten-copper composite module provided by the embodiment 1 of the application; Figure 4 An EDS diagram of the W-Cu continuous diffusion layer in the tungsten-copper composite module provided by the embodiment 1 of the application; Figure 5 A standard module schematic diagram obtained by post-processing provided by the embodiment 1 of the application.

[0026] Legend: 1-tungsten block, 2-copper cooling channel, 21-copper layer, 22-W-Cu continuous diffusion layer, 3-tungsten plate, 4-copper column.

[0027] The object, the function features and the advantages of the drawings will be further explained in the following with reference to the drawings. DETAILED DESCRIPTION

[0028] In order to make the object, the technical scheme and the advantages of the present application more clear, the present application will be described and explained in the following with reference to the embodiments. It should be understood that the specific embodiments described here are only used to explain the present application and not to limit the present application. Based on the embodiments provided by the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present application.

[0029] Obviously, the following description is only some examples or embodiments of the present application, and for those skilled in the art, the present application can also be applied to other similar situations without creative labor. In addition, it should be understood that although the efforts made in the development process may be complex and lengthy, some design, manufacture or production changes based on the technical content disclosed in the present application are only routine technical means for those skilled in the art related to the disclosed content of the present application, and should not be understood as insufficient disclosure of the present application.

[0030] However, there will be some unnecessary detailed description. For example, there are repeated descriptions of well-known matters and actual identical structures. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate understanding by those skilled in the art. In addition, the following description is provided to enable those skilled in the art to fully understand the present application and is not intended to limit the subject matter recited in the claims.

[0031] If not specifically stated, all embodiments and optional embodiments of the present application can be combined with each other to form new technical schemes, and all technical features and optional technical features of the present application can be combined with each other to form new technical schemes.

[0032] The first aspect of the embodiment of the present application provides a tungsten-copper composite module, as shown in the figure, comprising a tungsten block and a copper cooling channel in the tungsten block; from the inner wall of the copper cooling channel to the outside, comprising a copper layer and a W-Cu continuous diffusion layer; Figure 1 As shown in the figure, comprising a tungsten block and a copper cooling channel in the tungsten block; from the inner wall of the copper cooling channel to the outside, comprising a copper layer and a W-Cu continuous diffusion layer; Figure 1 In the figure, 1 is a tungsten block, 2 is a copper cooling channel, 21 is a copper layer, and 22 is a W-Cu continuous diffusion layer.

[0033] The tungsten-copper composite module provided by the embodiment of the present application adopts a W-Cu continuous diffusion layer metallurgical interface connection between copper and tungsten, which meets the extreme thermal load bearing requirements of the divertor module of the nuclear fusion device.

[0034] In some embodiments, the thickness of the copper layer is 1.0mm-2.0mm. In this case, the copper layer can quickly transfer heat.

[0035] In some embodiments, the thickness of the diffusion layer is 1um-5um. In this case, the combination between copper and tungsten is stable and not easy to fall off.

[0036] In some embodiments, the inner diameter of the copper cooling flow channel is 15mm-18mm.

[0037] The second aspect of the embodiment of the present application provides a preparation method of a tungsten-copper composite module, comprising the following steps: S10. After the tungsten plate embedded with the copper column is packaged, the hot isostatic pressing treatment is performed, and then the deep hole drilling processing is performed to obtain the tungsten-copper composite module; The deep hole drilling processing step comprises: hollowing out the center of the tungsten-copper composite module obtained after the hot isostatic pressing treatment to obtain the copper cooling flow channel.

[0038] The preparation method of the tungsten-copper composite module provided by the embodiment of the present application can realize the metallurgical combination of tungsten and copper by using single hot isostatic pressing treatment on the tungsten plate embedded with the copper column, realizes the high-reliability tungsten-copper interface connection, and meets the extreme thermal load bearing requirements of the divertor module of the nuclear fusion device.

[0039] In some embodiments, in the above step S10, the preparation of the tungsten plate embedded with the copper column comprises the following steps: S101. After drilling a plurality of through holes in the tungsten plate, a plurality of copper columns are embedded in the plurality of through holes; The difference between the hole diameter of the through hole and the diameter of the copper column is 0.05mm-0.10mm; After embedding the plurality of copper columns in the plurality of through holes, the structure of the tungsten plate is as shown in Figure 2 3 is the tungsten plate, and 4 is the copper column.

[0040] In the preparation of the tungsten plate embedded with the copper column, the copper column is embedded in the through hole, the difference between the hole diameter of the through hole and the diameter of the copper column is 0.05mm-0.10mm, a gap fit structure is formed between the copper column and the through hole, and the precise gap fit of the copper column and the through hole and the synergistic effect of the plastic deformation of the hot isostatic pressing make the tungsten and copper metallurgical combination form a continuous W-Cu diffusion layer.

[0041] In some embodiments, in the above step S101, the difference between the height of the copper column and the thickness of the tungsten plate is 0.5mm-3.0mm. In this case, the outer sleeve of the package extrudes the protruding soft copper column in the axial direction, the copper column expands radially, the copper cylindrical surface is in close contact with the inner wall of the tungsten hole, and diffusion occurs at high temperature to realize the metallurgical combination between tungsten and copper.

[0042] In some embodiments, in the above step S101, the grade of the copper column is TU1.

[0043] In some embodiments, in the step S101 above, the purity of the copper column is 99.99% or above.

[0044] In some embodiments, in the step S101 above, the diameter of the through hole is 15mm-18mm.

[0045] In some embodiments, in the step S101 above, the distance between adjacent through holes is 25mm-29mm.

[0046] In some embodiments, in the step S101 above, the inner wall surface roughness Ra of the through hole is ≤1μm. In this case, the low roughness can ensure that the surface of the inner wall of the through hole has no residual oxidation layer.

[0047] In some embodiments, in the step S101 above, the hole diameter tolerance of the several through holes is ±0.01mm.

[0048] In some embodiments, in the step S10 above, the purity of the tungsten plate is 99.95% or above.

[0049] In some embodiments, in the step S101 above, the density of the tungsten plate is 19.0 g / cm 3 and above.

[0050] In some embodiments, in the step S101 above, the thickness of the tungsten plate is 14mm-16mm.

[0051] In some embodiments, in the step S10 above, the packaging includes the following steps: S102. Place the tungsten plate containing the copper column into the packaging assembly, and vacuumize to 5×10 -3 Pa or above.

[0052] In some embodiments, in the step S102 above, in the packaging, the temperature during vacuumization is 290℃-310℃. In this case, the gas molecules inside the sleeve can be sufficiently extracted, and the vacuum degree inside the sleeve cavity can be improved.

[0053] In some embodiments, in the step S102 above, the packaging assembly is a 304 stainless steel sleeve packaging assembly.

[0054] In some embodiments, the wall thickness of the 304 stainless steel sleeve packaging assembly is 1mm-4mm. In this case, within this wall thickness range, the sleeve deforms at high temperature, and the pressure of the sleeve can axially extrude the copper column, so that the copper cylindrical surface fully matches the inner wall of the tungsten hole.

[0055] In some embodiments, in the step S10, the temperature of the hot isostatic pressing is 950-1050°C. In this case, the temperature of the hot isostatic pressing is lower than the melting point of copper, which can minimize the compressive strength of copper at high temperature, so that the copper column expands in the radial direction to fit the inner wall of the tungsten block, and the tungsten and copper are metallurgically combined.

[0056] In some embodiments, in the step S10, the pressure of the hot isostatic pressing is 100-150 MPa.

[0057] In some embodiments, in the step S10, the hot isostatic pressing comprises the following steps: S103. After the temperature is raised to the temperature of the hot isostatic pressing at a rate of 2-8°C / min in an inert atmosphere, the isostatic pressure is applied and the temperature is kept constant; finally, the temperature is cooled to below 200°C.

[0058] In the hot isostatic pressing, the copper column will undergo a radial plastic deformation of 15-20%, so as to completely fill the fitting gap between the through hole and the tungsten and form a metallurgical bond with the tungsten.

[0059] In some embodiments, in the step S103, the inert atmosphere is at least one of argon and helium.

[0060] In some embodiments, in the step S103, the holding time is 1-5 h.

[0061] In some embodiments, the preparation method of the tungsten-copper composite module provided in the above embodiments of the present application is used to prepare the tungsten-copper composite module provided in the embodiments of the present application.

[0062] The following will be further described in conjunction with specific embodiments.

[0063] For convenience of description, in the following examples and comparative examples: (1) The selected tungsten plate has a size (length x width x thickness) of 84 mm x 84 mm x 15 mm, a density of 19.1 g / cm 3 , and a purity of 99.95%.

[0064] (2) The selected copper column has a TU1 brand.

[0065] (3) The packaging assembly is a 304 stainless steel sheath packaging assembly, which has an inner cavity size (length x width x height) of 90 mm x 90 mm x 17 mm and a wall thickness of 3 mm.

[0066] Example 1 Example 1 provides a preparation method of a tungsten-copper composite module, as shown in Figure 2 , the steps are as follows: E1. Process a plurality of through holes E1-1. Drilling: 3x3 matrix distribution, through-hole diameter Φ16.00±0.05 mm, hole center distance 27 mm, 3x3 through holes are drilled on the tungsten plate.

[0067] E1-2. Through-hole inner wall treatment: finish machining to hole diameter Φ17.00±0.05 mm by numerical control lathe, roughness Ra 0.8 μm.

[0068] E2. Copper column assembly According to the through-hole diameter Φ17.00±0.05 mm obtained by processing step E1-2 and the thickness (15 mm) of the tungsten plate, 9 copper columns with a diameter of 16.9 mm and a height of 16 mm are selected, and the copper columns are pressed into the through holes one by one.

[0069] E3. Packaging The tungsten plate containing copper columns obtained in E2 is placed in a packaging assembly, laser sealed, and vacuumed to 3x10 -3 Pa at 300℃.

[0070] E4. Hot isostatic pressing After heating to 1000℃ at a rate of 5℃ / min under argon atmosphere, an isostatic pressure of 140 MPa is applied and held for 2h; finally cooled to below 200℃ and the tungsten-copper composite module is taken out.

[0071] E5. Post-processing On the tungsten-copper composite module, a Φ15 mm copper cooling channel (copper layer thickness 2.0 mm) is processed by deep hole drilling; Wire cutting is separated into 9 25mmx25mmx15mm modules (as shown in Figure 3 Fig. 1), and then the copper cooling channel of the module is machined to 16±0.05 mm.

[0072] Example 2 Example 2 provides a method for preparing a tungsten-copper composite module, the steps of which are basically the same as those of Example 1, except that: The hot isostatic pressing of step E4 is as follows: After heating to 950℃ at a rate of 8℃ / min under argon atmosphere, an isostatic pressure of 150 MPa is applied and held for 2h; finally cooled to below 200℃ and the tungsten-copper composite module is taken out.

[0073] Example 3 Example 3 provides a method for preparing a tungsten-copper composite module, the steps of which are basically the same as those of Example 1, except that: The hot isostatic pressing of step E4 is as follows: After the temperature is raised to 1050°C at a rate of 2°C / min under an argon atmosphere, an isostatic pressure of 100 MPa is applied and held for 1 h; finally, the tungsten-copper composite module is removed after cooling to below 200°C.

[0074] Example 4 Example 4 provides a method for preparing a tungsten-copper composite module, the steps of which are basically the same as those of Example 1, except that: In step E2, the height of the selected copper column is 15.5 mm.

[0075] Example 5 Example 5 provides a method for preparing a tungsten-copper composite module, the steps of which are basically the same as those of Example 1, except that: In step E2, the height of the selected copper column is 18 mm.

[0076] Example 6 Example 6 provides a method for preparing a tungsten-copper composite module, the steps of which are basically the same as those of Example 1, except that: In step E1, the hole diameter of the processed through hole is 15.95 mm.

[0077] Comparative Example 1 Comparative Example 1 provides a method for preparing a tungsten-copper composite module, the steps of which are basically the same as those of Example 1, except that: In the hot isostatic pressing of step E4, the hot isostatic pressing temperature is 1083.4°C and the hot isostatic pressing pressure is 90 MPa.

[0078] Comparative Example 2 Comparative Example 2 provides a method for preparing a tungsten-copper composite module, the steps of which are basically the same as those of Example 1, except that: In step E2, the height of the selected copper column is 15 mm.

[0079] Comparative Example 3 Comparative Example 3 provides a method for preparing a tungsten-copper composite module, the steps of which are as follows: A W block with a relative density of 91% is used to machine a W hole with a hole surface finish of 3.2. After the W block and the Cu tube are cleaned, they are assembled together. CuNiMn solder is placed at the W / Cu intersection, and vacuum brazing is performed at 1000°C for 30 minutes. The brazed W / Cu piece is subjected to hot isostatic pressing at 500°C and 200 MPa for 2 h, and after machining, a W / Cu composite component is obtained.

[0080] In order to verify the progressiveness of the tungsten-copper composite module and the preparation method thereof provided in the embodiments of the present application, the tungsten-copper composite modules prepared by the preparation methods provided in the embodiments of the present application and the comparative examples are subjected to diffusion layer thickness and interface bonding strength detection, and the results are shown in Table 1 below. Taking Example 1 and Comparative Example 1 as examples, the SEM is used to detect the morphology of the W-Cu continuous diffusion layer, and the SEM images obtained are shown in Figs. 1 and 2, respectively. Figure 3 and Figure 5 .

[0081] Table 1

[0082] From the above table and the accompanying drawings, at least the following conclusions can be drawn: (1) As can be seen from the data of Examples 1 to 7 and Comparative Example 1, in the preparation method of the tungsten-copper composite module provided in the embodiments of the present application, the hot isostatic pressing temperature is set to be lower than the melting point of copper, which can maximize the reduction of the strength of copper at high temperature, thereby improving the metallurgical bonding between copper and tungsten.

[0083] (2) As can be seen from the data of Example 1 and Comparative Example 2, in the preparation method of the tungsten-copper composite module provided in the embodiments of the present application, the difference between the height of the copper column and the thickness of the tungsten plate is 0.5 mm to 3.0 mm, and the outer sleeve of the package is extruded by the protruding soft copper column in the axial direction, so that the copper column expands radially, the copper cylindrical surface is in close contact with the inner wall of the tungsten hole, and diffusion occurs at high temperature, thereby realizing the metallurgical bonding between tungsten and copper.

[0084] (3) As can be seen from the data of Example 1 and Comparative Example 2, the interface bonding strength of the tungsten-copper composite module prepared by the preparation method of the tungsten-copper composite module provided in the embodiments of the present application is high, which is metallurgical bonding.

[0085] (4) As can be seen from the SEM images of Example 1 and Comparative Example 1, the thickness of the W-Cu continuous diffusion layer of the tungsten-copper composite module prepared by the preparation method of the tungsten-copper composite module provided in the embodiments of the present application can reach 3.5 μm, which further illustrates that the interface bonding strength of the tungsten-copper composite module is high.

[0086] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and embodiments having substantially the same structure and playing the same role and effect within the scope of the technical solutions of the present application are all included in the technical scope of the present application. In addition, within the scope of the main idea of the present application, various modifications that can be thought of by those skilled in the art, and other ways constructed by combining part of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A tungsten-copper composite module, comprising a tungsten block and copper cooling channels within the tungsten block; characterized in that, The copper cooling channel comprises a copper layer and a W-Cu continuous diffusion layer extending outward from its inner wall.

2. The tungsten-copper composite module according to claim 1, characterized in that, At least one of the following conditions (1) to (3) must be met: (1) The thickness of the copper layer is 1.0 mm to 2.0 mm; (2) The thickness of the diffusion layer is 1 μm to 5 μm; (3) The inner diameter of the copper cooling channel is 15mm~18mm.

3. A method for preparing a tungsten-copper composite module, characterized in that, Includes the following steps: After encapsulating the tungsten plate with embedded copper pillars, hot isostatic pressing is performed followed by deep hole drilling to obtain the tungsten-copper composite module. The deep hole drilling process includes: hollowing out the center of the tungsten-copper composite module obtained after hot isostatic pressing to obtain the copper cooling channel.

4. The method for preparing the tungsten-copper composite module according to claim 3, characterized in that, In the hot isostatic pressing process, at least one of the following conditions (1) to (3) is satisfied: (1) The hot isostatic pressing temperature is 950℃~1050℃; (2) The isostatic pressure is 100MPa~150MPa; (3) The hot isostatic pressing time is 0.5h~5h.

5. The method for preparing the tungsten-copper composite module according to claim 3 or 4, characterized in that, The hot isostatic pressing process includes the following steps: Under an inert atmosphere, the temperature is increased to the hot isostatic pressure temperature at a rate of 2℃ / min to 10℃ / min, then isostatic pressure is applied and the temperature is held; finally, it is cooled to below 200℃.

6. The method for preparing the tungsten-copper composite module according to claim 5, characterized in that, The preparation of the tungsten plate embedded with copper pillars includes the following steps: After drilling several through holes in a tungsten plate, several copper pillars are embedded in several of the through holes; The difference between the diameter of the through hole and the diameter of the copper pillar is 0.05mm to 0.10mm.

7. The method for preparing the tungsten-copper composite module according to claim 6, characterized in that, At least one of the following conditions (1) to (4) must be met: (1) The difference between the height of the copper pillar and the thickness of the tungsten plate is 0.5 mm to 3.0 mm; (2) The diameter of the through hole is 15mm~18mm; (3) The center-to-center distance between adjacent through holes is 25mm~29mm; (4) The thickness of the tungsten plate is 14mm~16mm.

8. The method for preparing the tungsten-copper composite module according to claim 3, characterized in that, The packaging process includes the following steps: A tungsten plate containing copper pillars is placed in the encapsulation assembly, and a vacuum is drawn to 5 × 10⁻⁶. -3 Pa or above.

9. The method for preparing the tungsten-copper composite module according to claim 8, characterized in that, During the encapsulation process, the temperature during vacuuming is 290℃~310℃.

10. An application of the tungsten-copper composite module as described in claim 1 or 2 in a divertor.

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