A method for connecting an ods-w / cu module based on self-propagating reaction

Abstract

The present application relates to the technical field of dissimilar metal connection, and relates to a method for connecting an ODS-W / Cu module based on self-propagating reaction, which comprises the following steps: pretreating base materials to obtain pretreated ODS-W plates and Cu plates; weighing Ti powder, Al powder and Ni powder to perform first ball milling treatment, obtaining Ti / Al / Ni mixed powder, adding anhydrous ethanol, polyvinyl butyral, polyvinylpyrrolidone and polyethylene glycol to the Ti / Al / Ni mixed powder to perform second ball milling treatment, obtaining Ti / Al / Ni self-propagating reaction casting slurry; casting and forming the de-bubbling treated Ti / Al / Ni self-propagating reaction casting slurry on the surface of the pretreated ODS-W plates, obtaining casting blanks on the surface of the ODS-W plates after drying, performing glue removal treatment, and obtaining Ti / Al / Ni self-propagating reaction casting blanks; fixing and combining the pretreated Cu plates, the Ti / Al / Ni self-propagating reaction casting blanks and the pretreated ODS-W plates, applying pressure, igniting the Ti / Al / Ni self-propagating reaction casting blanks under vacuum conditions, and obtaining connected ODS-W / Cu modules. The present application can effectively relieve residual stress caused by the difference in linear expansion coefficient between W / Cu.

Description

Technical Field

[0001] This invention relates to the field of dissimilar metal joining technology, and in particular to a method for joining ODS-W / Cu modules based on self-propagating reaction. Background Technology

[0002] As a crucial component of nuclear fusion devices, the divertor is primarily composed of plasma-facing materials and heat sink materials. Its function is to promptly remove dust, impurities, and heat generated during the nuclear fusion process, control the recirculation of impurity particles, and ensure the safe operation of the nuclear fusion reactor. W and W alloys possess advantages such as high temperature resistance, high sputtering resistance, and low hydrogen retention rate, making them leading candidates for plasma-facing materials (PFM) in future fusion devices. However, during the stable operation of a controlled nuclear fusion device, the plasma-facing material in the divertor is continuously subjected to impacts from highly charged particles, resulting in a high heat flux on its surface (Fusion Engineering and Design, 124(2017)1082-1085). Therefore, it is necessary to combine the plasma-facing material with heat sink materials (Cu and Cu alloys) with good thermal conductivity to promptly transfer the heat load on the surface of the plasma-facing component, ensuring the safe and reliable operation of the divertor component.

[0003] Currently, the connection between W and Cu mainly faces two problems: (1) the thermal expansion coefficients and Young's modulus of W and Cu differ greatly, which easily generates large thermal stress at the W / Cu interface, leading to the failure of the W / Cu joint at high temperatures; (2) W and Cu are not mutually soluble and do not form intermetallic compounds, thus failing to form a reliable metallurgical bond, resulting in a low joint strength when directly connected. In order to alleviate the thermal stress of the joint and extend the service life of the fusion device, it is crucial to select appropriate connection technology and stress relief methods. As traditional connection technologies, brazing and diffusion welding are effective methods for preparing W / Cu modules, but their application in ODS-W / Cu connection is limited by high requirements for the surface condition of the sample to be welded and the connection temperature, long experimental cycles, and the inability to have a large sample size.

[0004] Therefore, there is an urgent need to develop a fast, energy-saving connection process that can effectively mitigate the differences in the thermophysical properties of the base materials, so as to achieve high-strength connection and thermal stress relief of ODS-W / Cu modules. Summary of the Invention

[0005] In view of this, in order to overcome the shortcomings of the prior art, the present invention provides a method for connecting ODS-W / Cu modules based on self-propagating reaction.

[0006] This invention provides a method for connecting an ODS-W / Cu module based on a self-propagating reaction, the method comprising:

[0007] Step 1: Pretreatment of base material

[0008] The surfaces of the ODS-W board and Cu board to be joined are ground and polished, ultrasonically cleaned in acetone solution, and then vacuum dried to obtain pretreated ODS-W board and Cu board.

[0009] Step 2: Preparation of Ti / Al / Ni self-propagating reaction casting slurry

[0010] Ti powder, Al powder and Ni powder are weighed according to the formula and subjected to the first ball milling treatment to obtain Ti / Al / Ni mixed powder. Anhydrous ethanol, polyvinyl butyral, polyvinylpyrrolidone and polyethylene glycol are added to the Ti / Al / Ni mixed powder according to the formula and subjected to the second ball milling treatment to obtain Ti / Al / Ni self-propagating reaction casting slurry.

[0011] Step 3: Preparation of Ti / Al / Ni self-propagating reaction cast iron blank

[0012] Ti / Al / Ni self-propagating reaction casting slurry was placed in a vacuum environment for defoaming treatment. The defoamed Ti / Al / Ni self-propagating reaction casting slurry was cast onto the surface of a pretreated ODS-W board. After drying, a casting preform was obtained on the surface of the ODS-W board. The casting preform was debonded to obtain a Ti / Al / Ni self-propagating reaction casting preform.

[0013] Step 4: ODS-W / Cu module connection preparation

[0014] The pretreated Cu plate, Ti / Al / Ni self-propagating reaction cast blank, and pretreated ODS-W plate are fixedly combined. Pressure is applied to the obtained component, and a self-propagating reaction is carried out by igniting the Ti / Al / Ni self-propagating reaction cast blank under vacuum conditions to obtain the connected ODS-W / Cu module.

[0015] Preferably, in the method for connecting ODS-W / Cu modules based on self-propagating reaction of the present invention, in step one, the density of the ODS-W plate and the Cu plate is not less than 99%, and the surface roughness Ra of the surfaces to be connected after grinding and polishing is not greater than 5μm.

[0016] Preferably, in the method for connecting ODS-W / Cu modules based on self-propagating reaction of the present invention, in step two, Ti powder, Al powder and Ni powder are weighed according to the ratio and subjected to a first ball milling treatment to obtain Ti / Al / Ni mixed powder, including: based on 100% of the total mass of each component, the corresponding powders are weighed according to the ratio of Ti 25wt.%-65wt.%, Ni 1wt.%-8wt.%, and the balance being Al, and placed in a ball mill jar for a first ball milling treatment, wherein the particle size of Ti powder is 10-33μm, the particle size of Al powder is 10-33μm, the particle size of Ni powder is 10-33μm, the first ball milling treatment time is 24h, the ball-to-material ratio is 5:1, and the rotation speed is 400r / min.

[0017] Preferably, in the method for connecting ODS-W / Cu modules based on self-propagating reaction of the present invention, in step two, anhydrous ethanol, polyvinyl butyral, polyvinylpyrrolidone and polyethylene glycol are added to the Ti / Al / Ni mixed powder according to the ratio for a second ball milling treatment, including: adding 32wt.% anhydrous ethanol, 1wt.% polyvinyl butyral, 1wt.% polyvinylpyrrolidone and 1wt.% polyethylene glycol to 65wt.% Ti / Al / Ni mixed powder, the second ball milling treatment time is 24h, the ball-to-material ratio is 5:1, and the rotation speed is 400r / min.

[0018] Preferably, in the method of connecting ODS-W / Cu modules based on self-propagating reaction of the present invention, in step three, the Ti / Al / Ni self-propagating reaction casting slurry is placed in a vacuum environment for defoaming treatment, including: vacuum defoaming in a vacuum environment with a vacuum degree of less than 10 Pa for 6 hours.

[0019] Preferably, in the method for connecting ODS-W / Cu modules based on self-propagating reaction of the present invention, in step three, the defoamed Ti / Al / Ni self-propagating reaction casting slurry is cast onto the surface of the pretreated ODS-W plate and dried to obtain a cast blank on the surface of the ODS-W plate. This includes: casting the defoamed Ti / Al / Ni self-propagating reaction casting slurry onto the surface of the pretreated ODS-W plate using a casting machine, vacuum drying at 80°C for 24 hours, and obtaining a cast blank with a thickness of 0.2-1 mm on the surface of the ODS-W plate, wherein the height of the casting machine scraper is 0.2 mm and the casting speed is 40 cm / min.

[0020] Preferably, in the method for connecting ODS-W / Cu modules based on self-propagating reaction of the present invention, step three involves removing the binder from the cast preform to obtain a Ti / Al / Ni self-propagating reaction cast preform, including: removing the binder from the cast preform using hydrogen gas to obtain a Ti / Al / Ni self-propagating reaction cast preform, wherein the binder removal temperature is 250-450℃ and the binder removal time is 0.5-2.5h.

[0021] Preferably, in the method of connecting ODS-W / Cu modules based on self-propagating reaction of the present invention, step four involves fixing and assembling the pretreated Cu plate, the Ti / Al / Ni self-propagating reaction cast blank, and the pretreated ODS-W plate, including: fixing the pretreated Cu plate, the Ti / Al / Ni self-propagating reaction cast blank, and the pretreated ODS-W plate from top to bottom to obtain a fixed assembly.

[0022] Preferably, in the method for connecting ODS-W / Cu modules based on self-propagating reaction of the present invention, step four involves applying pressure to the obtained component and conducting a self-propagating reaction by igniting a Ti / Al / Ni self-propagating reaction cast blank under vacuum conditions to obtain the connected ODS-W / Cu module. This includes: applying a pressure of 5-20 MPa to the obtained component and conducting a self-propagating reaction by igniting a Ti / Al / Ni self-propagating reaction cast blank under vacuum conditions with a vacuum degree of less than 10 Pa to obtain the connected ODS-W / Cu module.

[0023] Preferably, in the method for connecting ODS-W / Cu modules based on self-propagating reaction of the present invention, in step four, pressure is applied to the obtained component and a self-propagating reaction is carried out by igniting the Ti / Al / Ni self-propagating reaction cast blank under vacuum conditions to obtain the connected ODS-W / Cu module, including: using a molybdenum resistance wire to ignite the Ti / Al / Ni self-propagating reaction cast blank to carry out a self-propagating reaction.

[0024] The method for connecting ODS-W / Cu modules based on self-propagating reaction of the present invention has the following beneficial effects:

[0025] 1) Ti / Al / Ni self-propagating cast blanks are prepared by casting, and the exothermic reaction is used as the heat source for connection. The reaction products are used as the intermediate layer for connection, so as to achieve reliable metallurgical bonding at the joint interface, so as to achieve faster and more energy-saving preparation of ODS-W / Cu modules. The exothermic reaction of self-propagating reaction can further reduce the need for external heat source and high connection temperature. Especially in some high exothermic systems, it can achieve high temperatures that cannot be achieved by conventional heating methods. The reaction time is extremely short and the production efficiency is high.

[0026] 2) Using Ti / Al / Ni self-propagating cast blank as an intermediate layer effectively alleviates the thermal stress caused by the mismatch of thermal expansion coefficients of W and Cu. At the same time, Ti, Al, Ni have good miscibility with W and Cu, which can form a good metallurgical bonding interface and realize high-strength connection of W / Cu modules.

[0027] 3) The method of the present invention has low requirements for experimental equipment and connection temperature parameters. It can reduce the heat-affected zone of the parent material by local rapid heat release during the reaction process, avoid the destruction of the structure of heat-sensitive materials, and help protect the performance of the parent material. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a process flow diagram of a method for connecting ODS-W / Cu modules based on a self-propagating reaction, as described in exemplary embodiments 1-5 of the present invention.

[0030] Figure 2 The shear strength and tensile strength of the ODS-W / Cu modules prepared according to exemplary embodiments 1-5 of the present invention;

[0031] Figure 3 SEM images of the ODS-W / Cu module interface prepared according to exemplary embodiments 1-5 of the present invention;

[0032] Figure 4 SEM images of the ODS-W / Cu module interface and EDS energy spectra of different regions prepared according to exemplary embodiment 3 of the present invention;

[0033] Figure 5 EDS surface scan analysis image of the ODS-W / Cu module interface prepared according to exemplary embodiment 3 of the present invention;

[0034] Figure 6 DSC curve of Ti / Al / Ni self-propagating reaction cast blank prepared according to exemplary embodiment 3 of the present invention during the heating process;

[0035] Figure 7 Microhardness distribution along the cross section of the ODS-W / Cu module prepared according to exemplary embodiment 3 of the present invention. Detailed Implementation

[0036] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0037] It should be noted that, in the absence of conflict, the following embodiments and features can be combined with each other; and, based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0038] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this disclosure, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0039] Figure 1 This is a process flow diagram of the method for rapidly connecting ODS-W / Cu modules based on self-propagating reaction according to exemplary embodiments 1-5 of the present invention; Embodiments 1 to 5 of the present invention are... Figure 1 A preferred embodiment of the method shown.

[0040] Example 1

[0041] Step 1: Pretreatment of base material

[0042] The surfaces of the ODS-W board and Cu board to be joined are polished, ultrasonically cleaned in acetone solution, and then vacuum dried to obtain pretreated ODS-W board and Cu board. The density of the ODS-W board and Cu board is not less than 99%, and the surface roughness Ra of the surfaces to be joined after polishing is not greater than 5μm.

[0043] Step 2: Preparation of Ti / Al / Ni self-propagating reaction casting slurry

[0044] Based on 100% of the total mass of each component, powders were weighed according to the ratio of Ti (25 wt.%), Ni (6 wt.%), and the balance Al, and placed in a ball mill jar for the first ball milling treatment. The particle size of the Ti powder was 33 μm, the Al powder was 20 μm, and the Ni powder was 33 μm. The first ball milling treatment lasted 24 hours, the ball-to-powder ratio was 5:1, and the rotation speed was 400 r / min. Then, 32 wt.% anhydrous ethanol, 1 wt.% polyvinyl butyral, 1 wt.% polyvinylpyrrolidone, and 1 wt.% polyethylene glycol were added to the 65 wt.% Ti / Al / Ni mixed powder for a second ball milling treatment to obtain a Ti / Al / Ni self-propagating reaction casting slurry. The second ball milling treatment lasted 24 hours, the ball-to-powder ratio was 5:1, and the rotation speed was 400 r / min.

[0045] Step 3: Preparation of Ti / Al / Ni self-propagating reaction cast iron blank

[0046] The Ti / Al / Ni self-propagating reaction casting slurry was subjected to vacuum degassing at a vacuum level of less than 10 Pa for 6 hours. The degassed Ti / Al / Ni self-propagating reaction casting slurry was then cast onto a pretreated ODS-W board using a casting machine. The slurry was vacuum dried at 80℃ for 24 hours, resulting in a 0.2 mm thick cast preform on the ODS-W board. The casting machine blade height was 0.2 mm, and the casting speed was 40 cm / min. Hydrogen was then used to remove the binder from the cast preform to obtain a Ti / Al / Ni self-propagating reaction casting preform. The binder removal temperature was 300℃, and the removal time was 1 hour.

[0047] Step 4: ODS-W / Cu module connection preparation

[0048] The pretreated Cu plate, Ti / Al / Ni self-propagating reaction cast blank, and pretreated ODS-W plate are fixed from top to bottom to obtain a fixed assembly. A pressure of 5 MPa is applied to the obtained assembly, and the Ti / Al / Ni self-propagating reaction cast blank is ignited using a molybdenum resistance wire under vacuum conditions of less than 10 Pa to carry out a self-propagating reaction, thus obtaining a connected ODS-W / Cu module.

[0049] Example 2

[0050] Step 1: Pretreatment of base material

[0051] The surfaces of the ODS-W board and Cu board to be joined are polished, ultrasonically cleaned in acetone solution, and then vacuum dried to obtain pretreated ODS-W board and Cu board. The density of the ODS-W board and Cu board is not less than 99%, and the surface roughness Ra of the surfaces to be joined after polishing is not greater than 5μm.

[0052] Step 2: Preparation of Ti / Al / Ni self-propagating reaction casting slurry

[0053] Based on 100% of the total mass of each component, the corresponding powders were weighed and placed in a ball mill jar for a first ball milling treatment, with Ti powder having a particle size of 15 μm, Al powder having a particle size of 20 μm, and Ni powder having a particle size of 20 μm. The first ball milling treatment time was 24 h, the ball-to-powder ratio was 5:1, and the rotation speed was 400 r / min. Then, 32 wt.% anhydrous ethanol, 1 wt.% polyvinyl butyral, 1 wt.% polyvinylpyrrolidone, and 1 wt.% polyethylene glycol were added to the 65 wt.% Ti / Al / Ni mixed powder for a second ball milling treatment to obtain a Ti / Al / Ni self-propagating reaction casting slurry. The second ball milling treatment time was 24 h, the ball-to-powder ratio was 5:1, and the rotation speed was 400 r / min.

[0054] Step 3: Preparation of Ti / Al / Ni self-propagating reaction cast iron blank

[0055] The Ti / Al / Ni self-propagating reaction casting slurry was subjected to vacuum degassing at a vacuum level of less than 10 Pa for 6 hours. The degassed Ti / Al / Ni self-propagating reaction casting slurry was then cast onto a pretreated ODS-W board using a casting machine. The slurry was vacuum dried at 80℃ for 24 hours, resulting in a 0.8 mm thick cast preform on the ODS-W board. The casting machine blade height was 0.2 mm, and the casting speed was 40 cm / min. Hydrogen was then used to remove the binder from the cast preform to obtain a Ti / Al / Ni self-propagating reaction casting preform. The binder removal temperature was 400℃, and the removal time was 1.5 hours.

[0056] Step 4: ODS-W / Cu module connection preparation

[0057] The pretreated Cu plate, Ti / Al / Ni self-propagating reaction cast blank, and pretreated ODS-W plate are fixed from top to bottom to obtain a fixed assembly. A pressure of 15 MPa is applied to the obtained assembly, and the Ti / Al / Ni self-propagating reaction cast blank is ignited using a molybdenum resistance wire under vacuum conditions of less than 10 Pa to carry out a self-propagating reaction, thus obtaining a connected ODS-W / Cu module.

[0058] Example 3

[0059] Step 1: Pretreatment of base material

[0060] The surfaces of the ODS-W board and Cu board to be joined are polished, ultrasonically cleaned in acetone solution, and then vacuum dried to obtain pretreated ODS-W board and Cu board. The density of the ODS-W board and Cu board is not less than 99%, and the surface roughness Ra of the surfaces to be joined after polishing is not greater than 5μm.

[0061] Step 2: Preparation of Ti / Al / Ni self-propagating reaction casting slurry

[0062] Based on 100% of the total mass of each component, the corresponding powders were weighed and placed in a ball mill jar for a first ball milling treatment, with Ti powder having a particle size of 10 μm, Al powder having a particle size of 10 μm, and Ni powder having a particle size of 10 μm. The first ball milling treatment time was 24 h, the ball-to-powder ratio was 5:1, and the rotation speed was 400 r / min. Then, 32 wt.% anhydrous ethanol, 1 wt.% polyvinyl butyral, 1 wt.% polyvinylpyrrolidone, and 1 wt.% polyethylene glycol were added to 65 wt.% of the Ti / Al / Ni mixed powder for a second ball milling treatment to obtain a Ti / Al / Ni self-propagating reaction casting slurry. The second ball milling treatment time was 24 h, the ball-to-powder ratio was 5:1, and the rotation speed was 400 r / min.

[0063] Step 3: Preparation of Ti / Al / Ni self-propagating reaction cast iron blank

[0064] The Ti / Al / Ni self-propagating reaction casting slurry was subjected to vacuum degassing at a vacuum level of less than 10 Pa for 6 hours. The degassed Ti / Al / Ni self-propagating reaction casting slurry was then cast onto a pretreated ODS-W board using a casting machine. The slurry was vacuum dried at 80℃ for 24 hours, resulting in a 0.6 mm thick cast preform on the ODS-W board. The casting machine blade height was 0.2 mm, and the casting speed was 40 cm / min. Hydrogen was then used to remove the binder from the cast preform to obtain a Ti / Al / Ni self-propagating reaction casting preform. The binder removal temperature was 450℃, and the removal time was 2.5 hours.

[0065] Step 4: ODS-W / Cu module connection preparation

[0066] The pretreated Cu plate, Ti / Al / Ni self-propagating reaction cast blank, and pretreated ODS-W plate are fixed from top to bottom to obtain a fixed assembly. A pressure of 10 MPa is applied to the obtained assembly, and the Ti / Al / Ni self-propagating reaction cast blank is ignited using a molybdenum resistance wire under vacuum conditions of less than 10 Pa to carry out a self-propagating reaction, thus obtaining a connected ODS-W / Cu module.

[0067] Example 4

[0068] Step 1: Pretreatment of base material

[0069] The surfaces of the ODS-W board and Cu board to be joined are polished, ultrasonically cleaned in acetone solution, and then vacuum dried to obtain pretreated ODS-W board and Cu board. The density of the ODS-W board and Cu board is not less than 99%, and the surface roughness Ra of the surfaces to be joined after polishing is not greater than 5μm.

[0070] Step 2: Preparation of Ti / Al / Ni self-propagating reaction casting slurry

[0071] Based on 100% of the total mass of each component, the corresponding powders were weighed and placed in a ball mill jar for a first ball milling treatment, with Ti powder having a particle size of 20 μm, Al powder having a particle size of 33 μm, and Ni powder having a particle size of 15 μm. The first ball milling treatment time was 24 h, the ball-to-powder ratio was 5:1, and the rotation speed was 400 r / min. Then, 32 wt.% anhydrous ethanol, 1 wt.% polyvinyl butyral, 1 wt.% polyvinylpyrrolidone, and 1 wt.% polyethylene glycol were added to the 65 wt.% Ti / Al / Ni mixed powder for a second ball milling treatment to obtain a Ti / Al / Ni self-propagating reaction casting slurry. The second ball milling treatment time was 24 h, the ball-to-powder ratio was 5:1, and the rotation speed was 400 r / min.

[0072] Step 3: Preparation of Ti / Al / Ni self-propagating reaction cast iron blank

[0073] The Ti / Al / Ni self-propagating reaction casting slurry was subjected to vacuum degassing at a vacuum level of less than 10 Pa for 6 hours. The degassed Ti / Al / Ni self-propagating reaction casting slurry was then cast onto a pretreated ODS-W board using a casting machine. The slurry was vacuum dried at 80℃ for 24 hours, resulting in a 0.4 mm thick cast preform on the ODS-W board. The casting machine blade height was 0.2 mm, and the casting speed was 40 cm / min. Hydrogen was then used to remove the binder from the cast preform to obtain a Ti / Al / Ni self-propagating reaction casting preform. The binder removal temperature was 350℃, and the removal time was 2 hours.

[0074] Step 4: ODS-W / Cu module connection preparation

[0075] The pretreated Cu plate, Ti / Al / Ni self-propagating reaction cast blank, and pretreated ODS-W plate are fixed from top to bottom to obtain a fixed assembly. An 8 MPa pressure is applied to the obtained assembly, and the Ti / Al / Ni self-propagating reaction cast blank is ignited using a molybdenum resistance wire under vacuum conditions of less than 10 Pa to carry out a self-propagating reaction, thus obtaining a connected ODS-W / Cu module.

[0076] Example 5

[0077] Step 1: Pretreatment of base material

[0078] The surfaces of the ODS-W board and Cu board to be joined are polished, ultrasonically cleaned in acetone solution, and then vacuum dried to obtain pretreated ODS-W board and Cu board. The density of the ODS-W board and Cu board is not less than 99%, and the surface roughness Ra of the surfaces to be joined after polishing is not greater than 5μm.

[0079] Step 2: Preparation of Ti / Al / Ni self-propagating reaction casting slurry

[0080] Based on 100% of the total mass of each component, powders were weighed according to the ratio of Ti 65 wt.%, Ni 5 wt.%, and the balance Al, and placed in a ball mill jar for the first ball milling treatment. The particle size of Ti powder was 33 μm, Al powder was 20 μm, and Ni powder was 20 μm. The first ball milling treatment time was 24 h, the ball-to-powder ratio was 5:1, and the rotation speed was 400 r / min. Then, 32 wt.% anhydrous ethanol, 1 wt.% polyvinyl butyral, 1 wt.% polyvinylpyrrolidone, and 1 wt.% polyethylene glycol were added to the 65 wt.% Ti / Al / Ni mixed powder for the second ball milling treatment to obtain a Ti / Al / Ni self-propagating reaction casting slurry. The second ball milling treatment time was 24 h, the ball-to-powder ratio was 5:1, and the rotation speed was 400 r / min.

[0081] Step 3: Preparation of Ti / Al / Ni self-propagating reaction cast iron blank

[0082] The Ti / Al / Ni self-propagating reaction casting slurry was subjected to vacuum degassing at a vacuum level of less than 10 Pa for 6 hours. The degassed Ti / Al / Ni self-propagating reaction casting slurry was then cast onto a pretreated ODS-W board using a casting machine. The slurry was vacuum dried at 80℃ for 24 hours, resulting in a 1mm thick cast preform on the ODS-W board. The casting machine blade height was 0.2mm, and the casting speed was 40cm / min. Hydrogen was then used to remove the binder from the cast preform to obtain a Ti / Al / Ni self-propagating reaction casting preform. The binder removal temperature was 250℃, and the removal time was 0.5 hours.

[0083] Step 4: ODS-W / Cu module connection preparation

[0084] The pretreated Cu plate, Ti / Al / Ni self-propagating reaction cast blank, and pretreated ODS-W plate are fixed from top to bottom to obtain a fixed assembly. A pressure of 20 MPa is applied to the obtained assembly, and the Ti / Al / Ni self-propagating reaction cast blank is ignited using a molybdenum resistance wire under vacuum conditions of less than 10 Pa to carry out a self-propagating reaction, thus obtaining a connected ODS-W / Cu module.

[0085] Example 6

[0086] The ODS-W / Cu modules prepared in Examples 1-5 were cut into tensile and shear test samples using a wire cutting machine, and tensile and shear tests were performed on the ODS-W / Cu modules using a CMT5150 electronic universal testing machine. Figure 2 The shear strength and tensile strength of the ODS-W / Cu modules prepared according to exemplary embodiments 1-5 of the present invention; such as Figure 2 As shown, a comparison of the shear strength and tensile strength of the ODS-W / Cu modules prepared in Examples 1 to 5 reveals that the ODS-W / Cu module prepared in Example 3 has the highest shear strength and tensile strength, which are 108 MPa and 135 MPa, respectively.

[0087] The interface structure of the ODS-W / Cu modules prepared in Examples 1-5 was observed using a Hitachi SU8020 field emission scanning electron microscope, and the surface distribution of interface elements was analyzed and measured using an energy dispersive spectroscopy (EDS) instrument. Before observing the microstructure of the joint interface using SEM, the test surface of the sample was successively polished with 400-grit, 600-grit, 800-grit, 1200-grit, and 2000-grit sandpaper to obtain a smooth mirror surface before testing the sample. Figure 3 SEM images of the ODS-W / Cu module interface prepared according to exemplary embodiments 1-5 of the present invention; (a) is an SEM image of the ODS-W / Cu module interface prepared in Example 1, (b) is an SEM image of the ODS-W / Cu module interface prepared in Example 2, (c) is an SEM image of the ODS-W / Cu module interface prepared in Example 3, (d) is an SEM image of the ODS-W / Cu module interface prepared in Example 4, and (e) is an SEM image of the ODS-W / Cu module interface prepared in Example 5. Figure 3As shown in (a)-(e), the intermediate layer of the ODS-W / Cu modules prepared in Examples 1-5 of this invention is tightly bonded to the substrates on both sides, with a clear and continuous interface, and no defects such as cracks were found. The ODS-W / Cu modules prepared in different examples can all be divided into three regions: the ODS-W substrate (Region I), the Ti / Al / Ni reaction intermediate layer (Region II), and the Cu substrate (Region III). Compared to other examples, the interface structure of the ODS-W / Cu module prepared in Example 3 is flatter, exhibiting better stability.

[0088] Figure 4 SEM images of the ODS-W / Cu module interface and EDS energy dispersive spectra of different regions prepared according to exemplary embodiment 3 of the present invention are shown. (a) is the SEM morphology image of the interface, and (b)-(e) are the EDS energy dispersive spectra of different regions, respectively. Figure 4 As shown in (a), different shades of gray phase are formed in the intermediate layer region of the ODS-W / Cu joint, namely light gray phase (dot region 1), gray phase (dot region 2), dark gray phase (dot region 3), and dark gray phase (dot region 4). Combined with the EDS energy dispersive spectroscopy analysis results, it was found that both W and Cu elements diffused into the intermediate layer to varying degrees.

[0089] To further observe the distribution of elements near the interface Figure 5 The images shown are EDS surface scan analysis diagrams of the ODS-W / Cu module interface prepared according to Example 3 of the present invention. (a) is a SEM morphology diagram of the interface, and (b)-(f) correspond to the surface scan analysis results of W, Cu, Ti, Al, and Ni elements, respectively. Figure 5 As shown in (a)-(f), the concentrations of W, Cu, and Ti elements show the most significant trends and are enriched at the interfaces, indicating the formation of a metallurgical diffusion layer with a continuous elemental distribution between the matrix and the intermediate layer. Furthermore, the diffusion degree of Cu into the intermediate layer is much higher than that of W into the intermediate layer and Ti into the matrix, suggesting that Cu is more readily diffused. The contents of Al and Ni elements in the intermediate layer region remain essentially unchanged, indicating their uniform distribution within the interlayer.

[0090] The relationship between internal heat and temperature of Ti / Al / Ni mixed powder under heating was measured using a NETZSCH differential thermal analyzer (Germany), and thermal analysis was performed by measuring the changes in internal heat of the sample. High-purity argon was used as the protective atmosphere, the heating temperature was 800℃, the heating rate was 10℃ / min, and alumina ceramic was used as the crucible to measure the heat released by the reaction within this temperature range. Figure 6 The DSC curve of the Ti / Al / Ni self-propagating reaction cast green body prepared according to exemplary embodiment 3 of the present invention during the heating process; as shown Figure 6As shown, no significant heat change was observed during the initial heating stage, indicating that no reaction occurred at this stage. When the temperature rose to 630.2℃, a significant exothermic peak appeared, with an area of ​​59.79 J / g, indicating that a vigorous exothermic reaction occurred in the Ti / Al / Ni self-propagating reaction preform at this temperature, releasing a large amount of heat. After the reaction was completed, the sample temperature rapidly dropped to near the furnace temperature and then cooled to room temperature with the furnace.

[0091] The Vickers hardness of each area of ​​the joint was measured using an HV-120 Vickers hardness tester. The test load was 9.8 N and the loading time was 15 s. In order to reduce the measurement error, the average value of each point was taken as the microhardness of the sample. Figure 7 This is a microhardness distribution diagram along the cross-section of the ODS-W / Cu module prepared in Example 3 of the present invention. As can be seen from the figure, due to the different microstructures and phases in different regions of the joint, the microhardness of the joint varies significantly. The overall microhardness of the joint gradually decreases along the direction from ODS-W to Cu. This continuous change in microhardness helps to alleviate the residual stress of the ODS-W / Cu module and achieve a reliable connection between ODS-W and Cu. Furthermore, the microhardness variation trend in the intermediate layer region is much higher than that in the two side substrates, which may be caused by the uneven phase distribution in the intermediate layer.

[0092] The method for connecting ODS-W / Cu modules based on self-propagating reaction of the present invention has the following beneficial effects:

[0093] 1) Ti / Al / Ni self-propagating cast blanks are prepared by casting, and the exothermic reaction is used as the heat source for connection. The reaction products are used as the intermediate layer for connection, so as to achieve reliable metallurgical bonding at the joint interface, so as to achieve faster and more energy-saving preparation of ODS-W / Cu modules. The exothermic reaction of self-propagating reaction can further reduce the need for external heat source and high connection temperature. Especially in some high exothermic systems, it can achieve high temperatures that cannot be achieved by conventional heating methods. The reaction time is extremely short and the production efficiency is high.

[0094] 2) Using Ti / Al / Ni self-propagating cast blank as an intermediate layer effectively alleviates the thermal stress caused by the mismatch of thermal expansion coefficients of W and Cu. At the same time, Ti, Al, Ni have good miscibility with W and Cu, which can form a good metallurgical bonding interface and realize high-strength connection of W / Cu modules.

[0095] 3) The method of the present invention has low requirements for experimental equipment and connection temperature parameters. It can reduce the heat-affected zone of the parent material by local rapid heat release during the reaction process, avoid the destruction of the structure of heat-sensitive materials, and help protect the performance of the parent material.

[0096] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for connecting ODS-W / Cu modules based on self-propagating reaction, characterized in that, The method includes: Step 1: Pretreatment of base material The surfaces of the ODS-W board and Cu board to be joined are ground and polished, ultrasonically cleaned in acetone solution, and then vacuum dried to obtain pretreated ODS-W board and Cu board. Step 2: Preparation of Ti / Al / Ni self-propagating reaction casting slurry Ti powder, Al powder and Ni powder are weighed according to the formula and subjected to the first ball milling treatment to obtain Ti / Al / Ni mixed powder. Anhydrous ethanol, polyvinyl butyral, polyvinylpyrrolidone and polyethylene glycol are added to the Ti / Al / Ni mixed powder according to the formula and subjected to the second ball milling treatment to obtain Ti / Al / Ni self-propagating reaction casting slurry. Step 3: Preparation of Ti / Al / Ni self-propagating reaction cast iron blank Ti / Al / Ni self-propagating reaction casting slurry was placed in a vacuum environment for defoaming treatment. The defoamed Ti / Al / Ni self-propagating reaction casting slurry was cast onto the surface of a pretreated ODS-W board. After drying, a casting preform was obtained on the surface of the ODS-W board. The casting preform was debonded to obtain a Ti / Al / Ni self-propagating reaction casting preform. Step 4: ODS-W / Cu module connection preparation The pretreated Cu plate, Ti / Al / Ni self-propagating reaction cast blank and pretreated ODS-W plate are fixedly combined. Pressure is applied to the obtained component and a self-propagating reaction is carried out by igniting the Ti / Al / Ni self-propagating reaction cast blank under vacuum conditions to obtain the connected ODS-W / Cu module. In step two, Ti powder, Al powder, and Ni powder are weighed according to the formula and subjected to a first ball milling process to obtain Ti / Al / Ni mixed powder. The powder consists of Ti powder weighed at 25wt.%-65wt.%, Ni powder weighed at 1wt.%-8wt.%, with the remainder being Al, and placed in a ball mill jar for a first ball milling process. The particle size of Ti powder is 10-33µm, the particle size of Al powder is 10-33µm, and the particle size of Ni powder is 10-33µm. The first ball milling process takes 24 hours, the ball-to-powder ratio is 5:1, and the rotation speed is 400 r / min.

2. The method for connecting an ODS-W / Cu module based on a self-propagating reaction according to claim 1, characterized in that, In step one, the density of the ODS-W board and the Cu board shall not be less than 99%, and the surface roughness Ra of the surfaces to be joined after grinding and polishing shall not be greater than 5µm.

3. The method for connecting an ODS-W / Cu module based on a self-propagating reaction according to claim 1, characterized in that, In step two, anhydrous ethanol, polyvinyl butyral, polyvinylpyrrolidone, and polyethylene glycol are added to the Ti / Al / Ni mixed powder according to the specified ratio for a second ball milling treatment. This includes adding 32 wt.% anhydrous ethanol, 1 wt.% polyvinyl butyral, 1 wt.% polyvinylpyrrolidone, and 1 wt.% polyethylene glycol to 65 wt.% Ti / Al / Ni mixed powder. The second ball milling treatment lasts for 24 hours, with a ball-to-powder ratio of 5:1 and a rotation speed of 400 r / min.

4. The method for connecting an ODS-W / Cu module based on a self-propagating reaction according to claim 1, characterized in that, In step three, the Ti / Al / Ni self-propagating reaction casting slurry is placed in a vacuum environment for defoaming treatment, including: vacuum defoaming in a vacuum environment with a vacuum degree of less than 10 Pa for 6 hours.

5. The method for connecting an ODS-W / Cu module based on a self-propagating reaction according to claim 1, characterized in that, In step three, the defoamed Ti / Al / Ni self-propagating reaction casting slurry is cast onto the pretreated ODS-W board surface and dried to obtain a cast blank on the ODS-W board surface. This includes: casting the defoamed Ti / Al / Ni self-propagating reaction casting slurry onto the pretreated ODS-W board surface using a casting machine, vacuum drying at 80℃ for 24h, and obtaining a cast blank with a thickness of 0.2-1mm on the ODS-W board surface. The casting machine scraper height is 0.2mm and the casting speed is 40cm / min.

6. The method for connecting an ODS-W / Cu module based on a self-propagating reaction according to claim 1, characterized in that, In step three, the cast iron blank is subjected to a debinding treatment to obtain a Ti / Al / Ni self-propagating reaction cast iron blank, including: using hydrogen to debind the cast iron blank to obtain a Ti / Al / Ni self-propagating reaction cast iron blank, wherein the debinding temperature is 250-450℃ and the debinding time is 0.5-2.5h.

7. The method for connecting an ODS-W / Cu module based on a self-propagating reaction according to claim 1, characterized in that, In step four, the pretreated Cu plate, Ti / Al / Ni self-propagating reaction cast blank, and pretreated ODS-W plate are fixedly assembled, including: fixing the pretreated Cu plate, Ti / Al / Ni self-propagating reaction cast blank, and pretreated ODS-W plate from top to bottom to obtain a fixed assembly.

8. The method for connecting an ODS-W / Cu module based on a self-propagating reaction according to claim 1, characterized in that, In step four, pressure is applied to the obtained component and a self-propagating reaction is carried out by igniting the Ti / Al / Ni self-propagating reaction cast blank under vacuum conditions to obtain the joined ODS-W / Cu module. This includes: applying a pressure of 5-20 MPa to the obtained component and carrying out a self-propagating reaction by igniting the Ti / Al / Ni self-propagating reaction cast blank under vacuum conditions with a vacuum degree of less than 10 Pa to obtain the joined ODS-W / Cu module.

9. The method for connecting an ODS-W / Cu module based on a self-propagating reaction according to claim 1, characterized in that, In step four, pressure is applied to the obtained component and a self-propagating reaction is carried out by igniting the Ti / Al / Ni self-propagating reaction cast blank under vacuum conditions to obtain the connected ODS-W / Cu module, including: using a molybdenum resistance wire to ignite the Ti / Al / Ni self-propagating reaction cast blank to carry out a self-propagating reaction.

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