Preparation method of high-thermal-conductivity copper / molybdenum / copper laminated composite material

Abstract

The present disclosure provides a high-thermal-conductivity copper / molybdenum / copper layered composite material preparation method, comprising: assembling and placing copper plates-molybdenum plates-copper plates alternately in a graphite mold in sequence, carrying out melt infiltration connection in a melt infiltration sintering furnace, and then carrying out high-energy electric pulse treatment to obtain a high-thermal-conductivity copper / molybdenum / copper layered composite material; wherein the pulse voltage is 20 V-70 V, the pulse frequency is 200 Hz-400 Hz, the pulse time is 10 s-30 s, and the pulse current direction is parallel to the copper / molybdenum / copper layered composite material interface. The present disclosure adopts melt infiltration connection integrated forming and electric pulse post-treatment technology, forms a continuous solid solution layer with a thickness of about 1-2 microns on the Cu-Mo mutual insoluble system interface by optimizing the structure parameters under a specific current direction, realizes high-reliability connection of the copper / molybdenum / copper interface, and improves the comprehensive performance of the copper / molybdenum / copper layered composite material.

Description

Technical Field

[0001] This patent belongs to the field of interface control technology for dissimilar metal materials, specifically, it relates to a method for preparing a high thermal conductivity copper / molybdenum / copper layered composite material. Background Technology

[0002] As artificial intelligence and semiconductor technology advance towards integration, miniaturization, and high computing power, electronic packaging materials face significant challenges, including high thermal conductivity, low thermal expansion, and strong interface synergy optimization. Copper / molybdenum / copper (Cu / Mo / Cu, CMC) layered composites have attracted widespread attention from researchers due to their combination of copper's high thermal conductivity and molybdenum's low coefficient of thermal expansion. Furthermore, the coefficient of thermal expansion of CMC composites can be precisely controlled by varying the layer thickness ratio.

[0003] Extensive research has been conducted by scholars both domestically and internationally on the regulation of the copper-molybdenum interface structure to obtain CMC layered composite materials with excellent performance. Song Peng et al. (Influence of Mo–Cu core material surface state on the interfacial bonding of multilayer Cu / MoCu / Cu composite materials [J]. Powder Metallurgy Technology, 2023, 41(3): 249-254) investigated the effects of grinding and wire drawing on the interfacial bonding of copper / molybdenum copper / copper composite materials and revealed the interfacial bonding mechanism. The results showed that the leakage rate of the 5-layer Cu / MoCu / Cu composite material prepared using the wire-drawn core material was less than 5 × 10⁻⁶. -3 Pa·cm 3 ·s -1 The interlayer bonding strength is high. However, interfacial metallurgical bonding has not been achieved, and the means of controlling the heterogeneous interface structure are relatively simple, making it difficult to achieve synergistic control of the interface structure and the matrix structure. Ye Lisha et al. (Study on Cu surface alloying with Mo under high current pulsed electron beam irradiation [J]. Journal of Vacuum Science and Technology, 2024, 44(03): 258-265.) studied the effects of different pulse numbers on the solid solubility, phase structure and surface hardness of the material. The results showed that high current pulsed electron beam irradiation can effectively improve the solid solubility of Cu-Mo immiscible system. However, their treatment method only affects the surface and does not optimize the overall performance of the composite material. At present, how to improve the interfacial metallurgical bonding of immiscible metals such as copper and molybdenum still has certain challenges. Summary of the Invention

[0004] To address the problems mentioned above, this invention proposes a method for preparing a high thermal conductivity copper / molybdenum / copper layered composite material. This method employs integrated melting and infiltration bonding molding and electrical pulse post-processing technology. By optimizing structural parameters under a specific current direction, a continuous solid solution layer of 1-2 μm thickness is formed at the interface of the Cu-Mo non-solid-solid system, achieving highly reliable bonding at the copper / molybdenum / copper interface and improving the overall performance of the copper / molybdenum / copper layered composite material.

[0005] Specifically, a method for preparing a high thermal conductivity copper / molybdenum / copper layered composite material includes: Step 1: Prepare and pre-treat copper and molybdenum plates, and assemble them into a copper / molybdenum / copper composite billet by stacking them alternately in the order of copper plate-molybdenum plate-copper plate, and place them into a graphite mold; wherein the length difference X between the molybdenum plate and the copper plate is 19 mm to 39 mm. Step 2: The assembled molybdenum / copper composite billet is melt-infiltrated and joined in a melting and infiltrating sintering furnace, and then cooled to room temperature under a protective atmosphere to obtain a copper / molybdenum / copper layered composite billet. Step 3: Perform high-energy electric pulse treatment on the copper / molybdenum / copper layered composite preform to obtain a high thermal conductivity copper / molybdenum / copper layered composite material. The electric pulse parameters are as follows: pulse voltage is 20 V~70 V, pulse frequency is 200 Hz~400 Hz, pulse time is 10 s~30 s, and the pulse current direction is parallel to the interface of the copper / molybdenum / copper layered composite material.

[0006] As a further explanation of the present invention, after high-energy electrical pulse treatment, a continuous solid solution layer is formed at the copper / molybdenum interface of the copper / molybdenum / copper layered composite material, and the thickness of the solid solution layer is 1μm~2μm.

[0007] As a further explanation of the present invention, in step one, during the pretreatment process, the surfaces of the copper plate and the molybdenum plate are polished sequentially using sandpaper of grades 80#, 400#, 600#, 800#, 1000#, 1500#, and 2000#. Then, the copper plate is degreased with acetone to remove adhering contaminants. The molybdenum plate is acid-washed with dilute nitric acid. Subsequently, the copper plate and the molybdenum plate are ultrasonically cleaned in anhydrous ethanol for 10 min to 30 min to remove impurities from the surface of the plates. Finally, they are taken out and dried.

[0008] As a further explanation of the present invention, in step one, the graphite mold is provided with a fixing groove for fixing the molybdenum plate, and there is a 1mm to 2mm margin between the assembled copper / molybdenum / copper composite billet and the graphite mold.

[0009] As a further explanation of the present invention, in step one, the copper plate has a length of 51 mm and the molybdenum plate has a length of 70 mm to 90 mm.

[0010] As a further explanation of the present invention, in step two, the melting and infiltration sintering parameters are: heating rate of 5~10℃ / min, melting and infiltration temperature of 1250℃~1450℃, and holding time of 90min~150min.

[0011] As a further explanation of the present invention, in step two, the melting and infiltration sintering process is carried out in an H2 atmosphere.

[0012] As a further explanation of the present invention, the preparation method further includes ultrasonically cleaning the copper / molybdenum / copper layered composite plate after high-energy electrical pulse treatment in anhydrous ethanol to remove impurities on the plate surface, and then drying the plate surface to obtain a high-performance copper / molybdenum / copper layered composite material with high interfacial bonding.

[0013] Compared with the prior art, the technical solution disclosed herein has the following beneficial technical effects: This invention employs melt infiltration sintering combined with a specialized mold to directly prepare samples with the desired structure. Furthermore, it utilizes high-pulse current parameters to enhance the bonding strength and thermophysical properties of the Cu / Mo interface, thereby achieving efficient and high-quality preparation of copper / molybdenum / copper layered composite materials. Through a unique current path design and optimization of structural parameters (X-value), a continuous solid solution layer thickness of 1-2 μm is formed at the interface of the Cu-Mo non-solid-solid system, effectively achieving highly reliable bonding at the copper / molybdenum / copper interface. Simultaneously, the thermal conductivity and coefficient of thermal expansion of the material are optimized, thus achieving synergistic optimization of high thermal conductivity, low expansion, and strong interface in CMC materials.

[0014] This invention can significantly reduce lengthy preparation steps, expand the range of application of pulse current parameters, and provide theoretical support and practical basis for industrial application.

[0015] The above description is merely an overview of the technical solutions of the embodiments of this application. In order to better understand the technical means of the embodiments of this application and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of this application more obvious and understandable, specific implementation methods of this application are described below. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings of the embodiments will be briefly described below. It should be understood that the drawings described below only relate to some embodiments of this disclosure and are not intended to limit this disclosure, wherein: Figure 1 This is a technical roadmap provided by the present invention; Figure 2 This is a schematic diagram of the copper / molybdenum / copper layered composite material fixing structure of the present invention; Figure 3 This is the microstructure of the copper / molybdenum bonding interface after an electrical pulse in Embodiment 1 of the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are also within the scope of protection of this disclosure.

[0018] The term "embodiment" as used herein means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of the phrase "embodiment" in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0019] This invention addresses the efficient preparation of copper / molybdenum / copper layered composite materials. First, a uniquely structured mold is designed to fix copper and molybdenum sheets into the desired configuration, providing a physical basis for subsequently changing the pulsed current from a vertical to a parallel direction. Next, a melt-infiltration sintering furnace is used to melt-infiltrate and connect the fixed copper and molybdenum sheets, achieving interfacial solid-liquid metallurgical bonding. Finally, a high-energy electric pulse is used for short-time, efficient post-treatment of the CMC layered composite material, further enhancing the diffusion and solid solution of copper and molybdenum atoms, repairing interfacial defects, and promoting the evolution of the melt-infiltrated interface structure. A micron-level solid solution layer is generated on the Cu side interface, achieving highly reliable bonding of the copper / molybdenum / copper interface, ultimately realizing the efficient preparation of copper / molybdenum / copper layered composite materials with excellent performance.

[0020] like Figure 1 As shown, this invention provides a method for preparing a high thermal conductivity copper / molybdenum / copper layered composite material, comprising the following steps: Step 1: Sample Preparation: Select flat copper and molybdenum plates with dimensions of 51×17×0.8 mm and 70~90×17×1 mm, respectively. Use sandpaper of grades 80#, 400#, 600#, 800#, 1000#, 1500#, and 2000# to polish their surfaces sequentially. The length difference X between the molybdenum and copper plates is preferably 19 mm~39 mm, for example, 19 mm, 23 mm, 25 mm, 27 mm, 30 mm, 33 mm, 35 mm, and 39 mm. Use acetone to degrease the copper plate and remove adhering contaminants. Use 15% dilute nitric acid to acid-wash the molybdenum plate. Then, ultrasonically clean both materials in anhydrous ethanol for 10~30 min to remove surface impurities. Remove and dry the surfaces. Assemble the processed copper and molybdenum plates alternately in the order Cu / Mo / Cu and place them into a pre-made graphite crucible mold with fixed slots. Figure 2 As shown, the unique structure improves the direction of pulse current action and enhances the effect of pulse current action. The slot is used to fix the molybdenum plate in the core of the composite material to prevent the molybdenum plate from collapsing and shifting when the interlayer copper plate is heated and melted into copper liquid. At the same time, a 1-2 mm allowance is reserved between the composite billet and the mold during the billet assembly process to prevent the graphite crucible from cracking due to the expansion of the billet when heated.

[0021] Step 2, Melt Infiltration Bonding: The assembled copper / molybdenum / copper composite billet is melt infiltrated and bonded in an H2 atmosphere using a melt infiltration sintering furnace, and then cooled to room temperature under a protective atmosphere to obtain a copper / molybdenum / copper layered composite billet; the melt infiltration bonding parameters are: heating rate of 5~10℃ / min, melt infiltration temperature of 1250℃~1450℃, and holding time of 90min~150min; Step 3, Electro-pulse Strengthening: High-energy electro-pulse treatment is applied to the copper / molybdenum / copper layered composite preform to enhance the bonding ability of the Cu / Mo interface and improve the performance of the Cu / Mo / Cu layered composite material. The electro-pulse parameters are as follows: the pulse voltage is preferably 20 V to 70 V, for example, 20 V, 40 V, 60 V, or 70 V; the pulse frequency is preferably 200 Hz to 400 Hz, for example, 200 Hz, 250 Hz, 300 Hz, 350 Hz, or 400 Hz; the pulse time is preferably 10 s to 30 s, for example, 10 s, 15 s, 20 s, 25 s, or 30 s; and the pulse current direction is parallel to the interface of the copper / molybdenum / copper layered composite material.

[0022] Step 4: Post-processing: Surface oxide removal is performed on the copper / molybdenum / copper layered composite material after electrical pulse treatment. Ultrasonic cleaning in anhydrous ethanol for 10-30 minutes removes impurities from the surface of the material. The material is then removed and dried to obtain a high-performance copper / molybdenum / copper layered composite material with excellent interfacial bonding.

[0023] This invention employs melt infiltration sintering combined with a specialized mold to directly fabricate samples with the desired structure. The designed length difference X between the molybdenum and copper plates plays a decisive role in the transition of the pulse current from the perpendicular to the interface direction to the parallel to the interface direction. It also plays a decisive role in the magnitude of the non-thermal force at the copper / molybdenum / copper interface, maximizing the effect of the electrical pulse treatment. If X is too large, the sample will overheat under the same parameters; if X is too small, the non-thermal effect will not be effective. Based on... Figure 2The Cu / Mo / Cu layered composite material fixing structure shown has a molybdenum plate in the middle layer that is longer than the copper plates above and below by X, so that the direction of the subsequent pulsed current is parallel to the sample surface. Compared with the path of the pulsed current perpendicular to the sample surface in the prior art, the pulsed current direction adopted in this invention (parallel to the interface of the layered composite material) is based on the resistance difference between Cu and Mo and the current distribution rule, so that most of the pulsed current flows through the Cu / Mo interface, thereby significantly improving the interfacial bonding ability and thermophysical properties of the Cu / Mo / Cu layered composite material. A 1-2 μm continuous solid solution layer is formed on the interface of the Cu-Mo non-solid-solid system, optimizing the thermal conductivity and thermal expansion coefficient of the composite material, thereby realizing the efficient and high-quality preparation of CMC layered composite materials.

[0024] The following is an explanation with reference to specific embodiments:

[0025] Example 1 A method for preparing a high thermal conductivity copper / molybdenum / copper layered composite material is provided, comprising the following steps: Step 1: Sample Preparation: Select flat copper and molybdenum plates with dimensions of 51×17×0.8 mm and 70×17×1 mm, respectively. Grind and polish their surfaces sequentially using sandpaper of grades 80#, 400#, 600#, 800#, 1000#, 1500#, and 2000#, with an X parameter of 19 mm. Degrease the copper plate with acetone to remove adhering contaminants; acid-wash the molybdenum plate with 15% dilute nitric acid. Then, ultrasonically clean both materials in anhydrous ethanol for 10 minutes to remove surface impurities, and finally dry them. The processed copper-molybdenum plates are stacked alternately in the order of Cu / Mo / Cu and assembled into a pre-made graphite crucible with a fixed slot. The unique structure improves the direction of the pulse current and enhances the effect of the pulse current. The slot fixes the molybdenum plate in the core of the composite material and prevents the molybdenum plate from collapsing and shifting when the interlayer copper plates are heated and melted into copper liquid. At the same time, a 1 mm allowance is reserved between the composite billet and the mold during the billet assembly process to prevent the graphite crucible from cracking due to the expansion of the billet when heated.

[0026] Step 2: Melt infiltration bonding: The assembled copper / molybdenum plates are sintered in an H2 atmosphere using a melt infiltration sintering furnace, and then cooled to room temperature under a protective atmosphere. The melt infiltration parameters and process are as follows: heating rate is 5 ℃ / min, melt infiltration temperature is 1250℃, and holding time is 150 min.

[0027] Step 3: Electro-pulse strengthening: High-energy electro-pulse treatment is applied to the processed copper / molybdenum / copper layered composite material to improve the bonding ability of the Cu / Mo interface and enhance the performance of the Cu / Mo / Cu layered composite material. The electro-pulse parameters are as follows: pulse voltage is 20 V, pulse frequency is 400 Hz, pulse time is 10 s, and the pulse current direction is parallel to the interface of the copper / molybdenum / copper layered composite material.

[0028] Step 4: Post-processing: Surface oxide removal is performed on the copper / molybdenum / copper layered composite material after electrical pulse treatment. The material is ultrasonically cleaned in anhydrous ethanol for 10 minutes to remove surface impurities. It is then removed and dried to obtain a high-performance copper / molybdenum / copper layered composite material with excellent interfacial bonding.

[0029] Performance and organization testing: The copper and molybdenum bonding interface of the copper / molybdenum / copper layered composite material was observed by scanning electron microscopy, and the thermal conductivity and coefficient of thermal expansion of the copper / molybdenum / copper layered composite material were tested by laser flash method and push rod method, respectively.

[0030] Example 2 A method for preparing a high thermal conductivity copper / molybdenum / copper layered composite material is provided, comprising the following steps: Step 1: Sample Preparation: Select flat copper and molybdenum plates with dimensions of 51×17×0.8 mm and 90×17×1 mm, respectively. Grind and polish their surfaces sequentially using sandpaper of grades 80#, 400#, 600#, 800#, 1000#, 1500#, and 2000#, with an X parameter of 39 mm. Degrease the copper plate with acetone to remove adhering contaminants; acid-wash the molybdenum plate with 15% dilute nitric acid. Then, ultrasonically clean both materials in anhydrous ethanol for 30 minutes to remove surface impurities, and finally dry them. The processed copper-molybdenum plates are stacked alternately in the order of Cu / Mo / Cu and assembled into a pre-made graphite crucible with a fixed slot. The unique structure improves the direction of the pulse current and enhances the effect of the pulse current. The slot fixes the molybdenum plate in the core of the composite material and prevents the molybdenum plate from collapsing and shifting when the interlayer copper plates are heated and melted into copper liquid. At the same time, a 2 mm allowance is reserved between the composite billet and the mold during the billet assembly process to prevent the graphite crucible from cracking due to the expansion of the billet when heated.

[0031] Step 2: Melt infiltration bonding: The assembled copper / molybdenum plates are sintered in an H2 atmosphere using a melt infiltration sintering furnace, and then cooled to room temperature under a protective atmosphere. The melt infiltration parameters and process are as follows: heating rate is 10℃ / min, melt infiltration temperature is 1450℃, and holding time is 90 min.

[0032] Step 3: Electro-pulse strengthening: High-energy electro-pulse treatment is applied to the processed copper / molybdenum / copper layered composite material to improve the bonding ability of the Cu / Mo interface and enhance the performance of the Cu / Mo / Cu layered composite material. The electro-pulse parameters are as follows: pulse voltage is 70 V, pulse frequency is 200 Hz, pulse time is 30 s, and the pulse current direction is parallel to the interface of the copper / molybdenum / copper layered composite material.

[0033] Step 4: Post-processing: Surface oxide removal is performed on the copper / molybdenum / copper layered composite material after electrical pulse treatment. The material is ultrasonically cleaned in anhydrous ethanol for 30 minutes to remove surface impurities. It is then removed and dried to obtain a high-performance copper / molybdenum / copper layered composite material with excellent interfacial bonding.

[0034] Performance and organization testing: The copper and molybdenum bonding interface of the copper / molybdenum / copper layered composite material was observed by scanning electron microscopy, and the thermal conductivity and coefficient of thermal expansion of the copper / molybdenum / copper layered composite material were tested by laser flash method and push rod method, respectively.

[0035] Example 3 A method for preparing a high thermal conductivity copper / molybdenum / copper layered composite material is provided, comprising the following steps: Step 1: Sample Preparation: Select flat copper and molybdenum plates with dimensions of 51×17×0.8 mm and 78×17×1 mm, respectively. Polish their surfaces sequentially using sandpaper of grades 80#, 400#, 600#, 800#, 1000#, 1500#, and 2000#, with an X parameter of 27 mm. Degrease the copper plate with acetone to remove adhering contaminants; acid-wash the molybdenum plate with 15% dilute nitric acid. Then, ultrasonically clean both materials in anhydrous ethanol for 20 minutes to remove surface impurities, and finally dry them. The processed copper-molybdenum plates are stacked alternately in the order of Cu / Mo / Cu and assembled into a pre-made graphite crucible with a fixed slot. The unique structure improves the direction of the pulse current and enhances the effect of the pulse current. The slot fixes the molybdenum plate in the core of the composite material and prevents the interlayer copper plates from collapsing and shifting when they are heated and melted into copper liquid. At the same time, a 1.5 mm allowance is reserved between the composite billet and the mold during the billet assembly process to prevent the graphite crucible from cracking due to the expansion of the billet when heated.

[0036] Step 2: Melt infiltration bonding: The assembled copper / molybdenum plates are sintered in an H2 atmosphere using a melt infiltration sintering furnace, and then cooled to room temperature under a protective atmosphere. The melt infiltration parameters and process are as follows: heating rate is 8 ℃ / min, melt infiltration temperature is 1350℃, and holding time is 120 min.

[0037] Step 3: Electro-pulse strengthening: High-energy electro-pulse treatment is applied to the processed copper / molybdenum / copper layered composite material to improve the bonding ability of the Cu / Mo interface and enhance the performance of the Cu / Mo / Cu layered composite material. The electro-pulse parameters are as follows: pulse voltage is 60 V, pulse frequency is 300 Hz, pulse time is 12 s, and the pulse current direction is parallel to the interface of the copper / molybdenum / copper layered composite material.

[0038] Step 4: Post-processing: Surface oxide removal is performed on the copper / molybdenum / copper layered composite material after electrical pulse treatment. The material is ultrasonically cleaned in anhydrous ethanol for 20 minutes to remove surface impurities. It is then removed and dried to obtain a high-performance copper / molybdenum / copper layered composite material with excellent interfacial bonding.

[0039] Performance and organization testing: The copper and molybdenum bonding interface of the copper / molybdenum / copper layered composite material was observed by scanning electron microscopy, and the thermal conductivity and coefficient of thermal expansion of the copper / molybdenum / copper layered composite material were tested by laser flash method and push rod method, respectively.

[0040] Figure 3 The image shows the microstructure of the copper / molybdenum bonding interface after an electrical pulse in Embodiment 1 of the present invention. As can be seen from the image, the interface is defect-free and a continuous solid solution layer with a thickness of about 1.2 μm has been formed, which enhances the bonding ability of the interface and effectively achieves a highly reliable bonding of the copper / molybdenum / copper interface.

[0041] Table 1 below shows the thermal conductivity and thermal expansion data of the copper / molybdenum / copper composite material before and after the electric pulse in Example 3 of the present invention. As can be seen from the table, after the electric pulse treatment provided by the present invention, the synergistic optimization of high thermal conductivity and low expansion of the copper / molybdenum / copper composite material is achieved.

[0042] Table 1. Comparison of properties of copper / molybdenum / copper layered composite materials before and after electrical pulse.

[0043] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for preparing a high thermal conductivity copper / molybdenum / copper layered composite material, characterized in that, The preparation method includes: Step 1: Prepare and pre-treat copper and molybdenum plates, and assemble them into a copper / molybdenum / copper composite billet by stacking them alternately in the order of copper plate-molybdenum plate-copper plate, and place them into a graphite mold; wherein the length difference X between the molybdenum plate and the copper plate is 19 mm to 39 mm. Step 2: The assembled copper / molybdenum / copper composite billet is melt-infiltrated and joined in a melting and infiltrating sintering furnace, and then cooled to room temperature under a protective atmosphere to obtain a copper / molybdenum / copper layered composite billet. Step 3: Perform high-energy electric pulse treatment on the copper / molybdenum / copper layered composite preform to obtain a high thermal conductivity copper / molybdenum / copper layered composite material. The electric pulse parameters are as follows: pulse voltage is 20 V~70 V, pulse frequency is 200 Hz~400 Hz, pulse time is 10 s~30 s, and the pulse current direction is parallel to the interface of the copper / molybdenum / copper layered composite material.

2. The preparation method according to claim 1, characterized in that, After being treated with a high-energy electrical pulse, a continuous solid solution layer is formed at the copper / molybdenum interface of the copper / molybdenum / copper layered composite material, and the thickness of the solid solution layer is 1μm~2μm.

3. The preparation method according to claim 1, characterized in that, In step one, during the pretreatment process, the surfaces of the copper plate and the molybdenum plate are polished sequentially using sandpaper of grades 80#, 400#, 600#, 800#, 1000#, 1500#, and 2000#. Then, acetone is used to degrease the surface of the copper plate to remove adhering contaminants. The molybdenum plate was acid-washed with dilute nitric acid, and then the copper plate and molybdenum plate were ultrasonically cleaned in anhydrous ethanol for 10 min to 30 min to remove impurities from the surface of the plates. The plates were then removed and dried.

4. The preparation method according to claim 1, characterized in that, In step one, the graphite mold is provided with a fixing slot for fixing the molybdenum plate, and there is a 1mm to 2mm margin between the assembled copper / molybdenum / copper composite billet and the graphite mold.

5. The preparation method according to claim 1, characterized in that, In step one, the copper plate is 51mm long and the molybdenum plate is 70mm~90mm long.

6. The preparation method according to claim 1, characterized in that, In step two, the melting and infiltration sintering parameters are: heating rate of 5~10℃ / min, melting and infiltration temperature of 1250℃~1450℃, and holding time of 90min~150min.

7. The preparation method according to claim 1, characterized in that, In step two, the melting and infiltration sintering process is carried out in an H2 atmosphere.

8. The preparation method according to claim 1, characterized in that, The preparation method further includes ultrasonically cleaning the copper / molybdenum / copper layered composite plate after high-energy electrical pulse treatment in anhydrous ethanol to remove impurities from the plate surface, and then drying the surface to obtain a high-performance copper / molybdenum / copper layered composite material with high interfacial bonding.

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