Microalloyed copper graphene composite material and preparation method thereof
By employing molecular-level coating and heat treatment methods involving polysaccharides and organic additives, the problems of inhomogeneity and loose bonding in the preparation process of microalloyed copper graphene composite materials were solved, resulting in high-performance microalloyed copper graphene composite materials suitable for high-density electronic packaging and interconnection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHIZIYANG MATERIALS TECHNOLOGY (GUANGZHOU) CO LTD
- Filing Date
- 2026-03-06
- Publication Date
- 2026-06-05
AI Technical Summary
In the existing technology, the preparation process of microalloyed copper-graphene composite materials has problems such as poor sphericity and flowability of copper powder, uneven dispersion of graphene on the surface of copper powder, loose bonding at the composite interface, non-uniformity of material composition and insufficient density, which affect its application in the field of high-density electronic packaging and interconnection.
A molecular-level coating method using polysaccharides and organic additives is employed to form a continuous and dense coating layer on the surface of micro-alloyed copper powder. This layer is then sintered in a hydrogen atmosphere to transform into a uniformly attached few-layer graphene or high-quality carbon layer. Furthermore, hot isostatic pressing and solution aging treatments are used to improve the material's compositional uniformity and interfacial bonding tightness.
The electrical conductivity, thermal conductivity, and mechanical properties of microalloyed copper-graphene composite materials have been significantly improved, meeting the stringent requirements of high-density electronic packaging and interconnection, reducing raw material costs, and improving the overall performance of the materials through precise control of the carbonization process.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of metal matrix composite materials technology, and relates to a microalloyed copper graphene composite material and its preparation method. Background Technology
[0002] As electronic devices rapidly evolve towards higher density, miniaturization, and higher performance, the field of advanced electronic packaging and interconnection places stringent demands on packaging materials. These materials must possess excellent high electrical conductivity, efficient thermal management capabilities, and reliable mechanical strength to meet the requirements of high-density interconnect structures and ensure the long-term stable operation of electronic devices.
[0003] Microalloyed copper alloys such as CuCrZr have become fundamental materials with great application potential in the field of electronic packaging due to their good electrical conductivity, excellent mechanical strength and machinability. Graphene-reinforced copper-based composites, on the other hand, rely on the ultra-high electrical and thermal conductivity of graphene to provide an effective way to further improve the electrothermal performance of packaging materials. The combination of the two provides a new idea for solving the application bottleneck of traditional packaging materials and has become a key research direction and core material selection in the current field of high-density electronic packaging.
[0004] However, existing technologies still have shortcomings in the preparation of microalloyed copper-graphene composite materials. For example, CuCrZr powder prepared by conventional methods is prone to poor sphericity and poor flowability, which is not conducive to subsequent powder mixing and molding. The composite of graphene and copper powder is mostly carried out by physical mixing, which makes it difficult to achieve uniform dispersion and tight bonding of graphene on the surface of copper powder, and easily leads to defects such as uneven composite interface and loose bonding. At the same time, traditional powder mixing and sintering processes cannot guarantee the uniformity of material composition and the density of the final product. These problems restrict each other and seriously affect the electrothermal performance and mechanical reliability of microalloyed copper-graphene composite materials, thus limiting their large-scale application in the field of high-density electronic packaging and interconnection, and failing to meet the stringent requirements of this field for material performance. Summary of the Invention
[0005] To address the shortcomings of existing technologies, the present invention aims to provide a microalloyed copper graphene composite material and its preparation method. The preparation method provided by the present invention involves molecular-level coating of polysaccharides and organic additives, which transforms the coating layer in situ into a few-layer graphene or high-quality carbon layer uniformly attached to the surface of microalloyed copper powder during sintering. This facilitates the acquisition of microalloyed copper graphene composite materials with uniform composition, tight interfacial bonding, and high density, thereby meeting the stringent requirements for material performance in high-density electronic packaging and interconnection.
[0006] To achieve this objective, the present invention adopts the following technical solution:
[0007] In a first aspect, the present invention provides a method for preparing a microalloyed copper-graphene composite material, the method comprising the following steps:
[0008] A polysaccharide solution is mixed with microalloyed copper powder, and the solvent is removed to obtain coated microalloyed copper powder; the coated microalloyed copper powder is sintered in a hydrogen atmosphere to obtain graphene-coated microalloyed copper powder; the graphene-coated microalloyed copper powder is subjected to hot isostatic pressing and solution aging to obtain the microalloyed copper-graphene composite material.
[0009] The solute in the polysaccharide solution includes polysaccharide and organic additives, wherein the polysaccharide has ≥10 carbon atoms.
[0010] Compared to existing technologies that use monosaccharides or oligosaccharides as carbon sources, this invention uses a polysaccharide solution containing polysaccharides to perform molecular-level coating of microalloyed copper powder, which has significant technical advantages: Because polysaccharides have longer molecular chains and more repeating units than monosaccharides, they can form a continuous and dense coating layer on the surface of the microalloyed copper powder. The carbon content per unit mass is much higher than that of monosaccharides or oligosaccharides. During sintering in a hydrogen atmosphere, it can be converted in situ into a few-layer graphene or high-quality carbon layer uniformly attached to the surface of the microalloyed copper powder, effectively avoiding the discontinuous and uneven carbon layer thickness that easily occurs with monosaccharide or oligosaccharide coating, and its poor adhesion to the microalloyed copper powder matrix. The graphene coating of microalloyed copper powder, after hot isostatic pressing and solution aging, allows the uniformly dispersed few-layer graphene or high-quality carbon layer to fully exert its excellent electrical conductivity, thermal conductivity and mechanical reinforcement, significantly improving the overall performance of the microalloyed copper graphene composite material. This results in products with uniform composition, tight interfacial bonding and high density, thus solving the problems of large performance fluctuations and limited reinforcement effects of composite materials caused by insufficient carbon source or uneven carbon layer distribution in the existing technology. This can meet the stringent requirements of high-density electronic packaging and interconnection for material performance.
[0011] In some embodiments, the polysaccharide includes any one or a combination of at least two of starch, cellulose, chitosan, or sodium alginate.
[0012] In some embodiments, the organic adjuvant includes any one or a combination of at least two of ascorbic acid, citric acid, polyvinylpyrrolidone, or sodium dodecylbenzenesulfonate.
[0013] In some embodiments, the amount of the polysaccharide solution is 50wt% to 60wt% of the microalloyed copper powder.
[0014] In some embodiments, the amount of the polysaccharide is 0.2wt% to 0.5wt% of the microalloyed copper powder.
[0015] In some embodiments, the amount of the organic additive is 10wt% to 15wt% of the microalloyed copper powder.
[0016] In some embodiments, the solvent for the polysaccharide solution may be anhydrous ethanol.
[0017] In some embodiments, the average particle size of the microalloyed copper powder is 50 μm to 100 μm.
[0018] In some embodiments, the microalloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.04wt%~0.7wt% and the mass percentage of Zr is 0.015wt%~0.35wt%.
[0019] In some embodiments, the sintering heating rate is 5°C / min to 10°C / min.
[0020] In some embodiments, the sintering temperature is 400°C to 500°C.
[0021] In some embodiments, the sintering time is 3 to 5 hours.
[0022] In some embodiments, the absolute pressure of the sintering is 50 mbar to 100 mbar.
[0023] In some embodiments, the gas used in the hydrogen atmosphere includes a mixture of nitrogen and hydrogen; in the mixture of nitrogen and hydrogen, the volume percentage of hydrogen is not less than 60 vol.
[0024] In some embodiments, the heating rate of the hot isostatic pressing is 5°C / min to 10°C / min.
[0025] In some embodiments, the temperature of the hot isostatic pressing is 900°C to 1050°C.
[0026] In some embodiments, the hot isostatic pressing time is 4 to 6 hours.
[0027] In some embodiments, the pressure of the hot isostatic pressing is 80 MPa to 150 MPa.
[0028] In some embodiments, the hot isostatic pressing is performed in an argon atmosphere.
[0029] In some embodiments, the solution aging temperature is 480°C to 520°C.
[0030] In some embodiments, the solution aging time is 2h to 5h.
[0031] In a second aspect, the present invention provides a microalloyed copper-graphene composite material, which is prepared by the preparation method described in the first aspect.
[0032] The numerical range described in this invention includes not only the point values listed above, but also any point values within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values included in the range.
[0033] Compared with the prior art, the present invention has the following beneficial effects:
[0034] (1) This invention uses a polysaccharide solution containing polysaccharides to coat micro-alloyed copper powder at the molecular level. Because polysaccharides have longer molecular chains and more repeating monosaccharide units, they can form a continuous and dense coating layer on the surface of the micro-alloyed copper powder. The carbon content per unit mass is much higher than that of monosaccharides or oligosaccharides. During sintering in a hydrogen atmosphere, it can be converted in situ into a few-layer graphene or high-quality carbon layer uniformly attached to the surface of the micro-alloyed copper powder, effectively avoiding problems such as discontinuous carbon layers, uneven thickness, and weak bonding with the micro-alloyed copper powder matrix that are prone to occur when coating with monosaccharides or oligosaccharides. The subsequent... After hot isostatic pressing and solution aging treatment, the uniformly dispersed few-layer graphene or high-quality carbon layer can give full play to its excellent electrical conductivity, thermal conductivity and mechanical reinforcement, significantly improving the comprehensive performance of microalloyed copper graphene composite material. This is conducive to obtaining products with uniform composition, tight interface bonding and high density, thus solving the problem of large performance fluctuation and limited reinforcement effect of composite materials caused by insufficient carbon source or uneven carbon layer distribution in the existing technology. It can meet the stringent requirements of high-density electronic packaging and interconnection for material performance.
[0035] (2) The present invention uses polysaccharides as carbon source, which greatly reduces the cost of raw materials and conforms to the concept of green manufacturing. Compared with the violent pyrolysis of small molecule monosaccharides or oligosaccharides, polysaccharides have a more gradual and phased thermal decomposition behavior, which is conducive to precise control of the carbonization process and obtaining a graphene coating layer with fewer defects and a higher degree of graphitization.
[0036] (3) The combination of polysaccharide and organic additives in this invention can introduce beneficial heteroatoms during the sintering process. These heteroatoms can modify the electronic structure of graphene and strengthen the interfacial bonding through interaction with copper. Detailed Implementation
[0037] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention.
[0038] The "range" disclosed in this invention can be defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of the specific range. This type of range definition can include or exclude endpoints; any endpoint can be independently included or excluded, and they can be arbitrarily combined, meaning any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60~120 and 80~110 are listed for specific parameters, it is understood that ranges of 60~110 and 80~120 are also expected. Furthermore, if minimum range values 1 and 2 are listed, and maximum range values 3, 4, and 5 are also listed, then the following ranges are all expected: 1~3, 1~4, 1~5, 2~3, 2~4, and 2~5. In this invention, unless otherwise stated, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0" and "5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is described as an integer ≥2, it is equivalent to listing integers such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc. For instance, when a parameter is described as an integer selected from "2~10", it is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9, and 10.
[0039] In this invention, "a combination of at least two" refers to a quantity greater than or equal to two, unless otherwise specified. For example, "any combination of one or at least two" means one or more or more items. It can be understood that when referring to "a combination of at least two," it refers to any suitable combination of multiple items, that is, a combination of "at least two" items carried out in a manner that does not conflict with and enables the implementation of this invention.
[0040] Unless otherwise specified, all embodiments and optional embodiments of the present invention can be combined with each other to form new technical solutions.
[0041] The term "embodiment" as used in this invention means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment or implementation of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this invention can be combined with other embodiments.
[0042] Those skilled in the art will understand that the order in which the steps are written in the methods of the various embodiments does not imply a strict execution order. The detailed execution order of each step should be determined by its function and possible internal logic. Unless otherwise specified, all steps of the present invention may be performed sequentially or randomly, but are preferably performed sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the method may also include step (c), meaning that step (c) can be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.
[0043] In this invention, open-ended technical features or solutions described using terms such as "comprising" do not exclude additional members beyond those listed unless otherwise specified. They can be considered as providing both closed-ended features or solutions comprised of the listed members and open-ended features or solutions that include additional members beyond the listed members. For example, A includes a1, a2, and a3. Unless otherwise specified, it may also include other members or exclude additional members. This can be considered as providing both technical features or solutions where "A is composed of a1, a2, and a3" or "A is selected from a1, a2, and a3," and technical features or solutions where "A includes not only a1, a2, and a3, but also other members."
[0044] In this invention, unless otherwise specified, the features or solutions corresponding to "and / or" include any one of two or more of the related listed items, as well as any and all combinations of the related listed items. These arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. For example, "A and / or B" represents a group consisting of A, B, and "a combination of A and B". "Containing A and / or B" can mean "containing A, containing B, and containing A and B", or "containing A, containing B, or containing A and B", and can be appropriately understood according to the context.
[0045] In this invention, the terms "first aspect," "second aspect," "third aspect," "fourth aspect," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first," "second," "third," "fourth," etc., serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on the quantity.
[0046] In this invention, "optional" means that something is optional, that is, it refers to either "with" or "without". If there are multiple "optional" options in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, then each "optional" option is independent.
[0047] An embodiment of the present invention provides a method for preparing a micro-alloyed copper-graphene composite material, the method comprising the following steps:
[0048] A polysaccharide solution is mixed with microalloyed copper powder, and the solvent is removed to obtain coated microalloyed copper powder; the coated microalloyed copper powder is sintered in a hydrogen atmosphere to obtain graphene-coated microalloyed copper powder; the graphene-coated microalloyed copper powder is subjected to hot isostatic pressing and solution aging to obtain the microalloyed copper-graphene composite material.
[0049] The solute in the polysaccharide solution includes polysaccharide and organic additives, wherein the polysaccharide has ≥10 carbon atoms.
[0050] Compared to existing technologies that use monosaccharides or oligosaccharides as carbon sources, this invention uses a polysaccharide solution containing polysaccharides to perform molecular-level coating of microalloyed copper powder, which has significant technical advantages: Because polysaccharides have longer molecular chains and more repeating units than monosaccharides, they can form a continuous and dense coating layer on the surface of the microalloyed copper powder. The carbon content per unit mass is much higher than that of monosaccharides or oligosaccharides. During sintering in a hydrogen atmosphere, it can be converted in situ into a few-layer graphene or high-quality carbon layer uniformly attached to the surface of the microalloyed copper powder, effectively avoiding the discontinuous and uneven carbon layer thickness that easily occurs with monosaccharide or oligosaccharide coating, and its poor adhesion to the microalloyed copper powder matrix. The graphene coating of microalloyed copper powder, after hot isostatic pressing and solution aging, allows the uniformly dispersed few-layer graphene or high-quality carbon layer to fully exert its excellent electrical conductivity, thermal conductivity and mechanical reinforcement, significantly improving the overall performance of the microalloyed copper graphene composite material. This results in products with uniform composition, tight interfacial bonding and high density, thus solving the problems of large performance fluctuations and limited reinforcement effects of composite materials caused by insufficient carbon source or uneven carbon layer distribution in the existing technology. This can meet the stringent requirements of high-density electronic packaging and interconnection for material performance.
[0051] In some embodiments, the polysaccharide includes any one or a combination of at least two of starch, cellulose, chitosan, or sodium alginate. Typical but non-limiting combinations include combinations of starch and cellulose, chitosan and sodium alginate, cellulose and sodium alginate, starch, cellulose and sodium alginate, starch, chitosan and sodium alginate, or starch, cellulose, chitosan and sodium alginate.
[0052] The organic additives used in this invention are organic compounds with reducing and / or dispersing functions.
[0053] In some embodiments, the organic adjuvant includes any one or a combination of at least two of ascorbic acid, citric acid, polyvinylpyrrolidone (PVP), or sodium dodecylbenzenesulfonate (SDBS). Typical but non-limiting combinations include combinations of ascorbic acid and citric acid, citric acid and PVP, PVP and SDBS, ascorbic acid, PVP and SDBS, citric acid, PVP and SDBS, or ascorbic acid, citric acid, PVP and SDBS.
[0054] In some embodiments, the polysaccharide solution is mixed with microalloyed copper powder in a protective atmosphere of inert gas and / or nitrogen, and the mixing method may be at least one of planetary ball milling, three-dimensional mixing or acoustic resonance.
[0055] In some embodiments, the amount of the polysaccharide solution is 50wt% to 60wt% of the microalloyed copper powder, for example, it can be 50wt%, 52wt%, 54wt%, 55wt%, 56wt%, 58wt% or 60wt%, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0056] In some embodiments, the amount of the polysaccharide is 0.2wt% to 0.5wt% of the microalloyed copper powder, for example, it can be 0.2wt%, 0.3wt%, 0.4wt% or 0.5wt%, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0057] In some embodiments, the amount of the organic additive is 10wt% to 15wt% of the microalloyed copper powder, for example, it can be 10wt%, 11wt%, 12wt%, 13wt%, 14wt% or 15wt%, but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0058] In some embodiments, the solvent for the polysaccharide solution may be anhydrous ethanol.
[0059] In some embodiments, the average particle size of the microalloyed copper powder is 50μm to 100μm, for example, it can be 50μm, 60μm, 70μm, 80μm, 90μm or 100μm, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0060] In some embodiments, the microalloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.04wt%~0.7wt% and the mass percentage of Zr is 0.015wt%~0.35wt%.
[0061] The mass percentage of Cr is 0.04wt% to 0.7wt%, for example, it can be 0.04wt%, 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt% or 0.7wt%, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0062] The Zr content is 0.015wt% to 0.35wt%, for example, it can be 0.015wt%, 0.05wt%, 0.1wt%, 0.15wt%, 0.2wt%, 0.25wt%, 0.3wt% or 0.35wt%, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0063] Optionally, the preparation method of micro-alloyed copper powder may be: mixing raw materials according to the formula, and performing vacuum induction melting at a temperature of 1500℃~1600℃ in a protective atmosphere to obtain an alloy melt; the alloy melt is then atomized to obtain micro-alloyed copper powder.
[0064] In some embodiments, the sintering heating rate is 5°C / min to 10°C / min, for example, it can be 5°C / min, 6°C / min, 7°C / min, 8°C / min, 9°C / min or 10°C / min, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0065] In some embodiments, the sintering temperature is 400°C to 500°C, for example, 400°C, 420°C, 450°C, 480°C or 500°C, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0066] In some embodiments, the sintering time is 3h to 5h, for example, it can be 3h, 3.5h, 4h, 4.5h or 5h, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0067] In some embodiments, the absolute pressure of the sintering is 50 mbar to 100 mbar, for example, it can be 50 mbar, 60 mbar, 70 mbar, 80 mbar, 90 mbar or 100 mbar, but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0068] In some embodiments, the gas used in the hydrogen atmosphere includes a mixture of nitrogen and hydrogen; in the mixture of nitrogen and hydrogen, the volume percentage of hydrogen is not less than 60 vol.
[0069] Optionally, in the nitrogen-hydrogen mixture, the volume ratio of nitrogen to hydrogen is 4:6.
[0070] In some embodiments, the heating rate of the hot isostatic pressing is 5°C / min to 10°C / min, for example, it can be 5°C / min, 6°C / min, 7°C / min, 8°C / min, 9°C / min or 10°C / min, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0071] In some embodiments, the temperature of the hot isostatic pressing is 900°C to 1050°C, for example, 900°C, 920°C, 950°C, 980°C, 1000°C, 1020°C or 1050°C, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0072] In some embodiments, the hot isostatic pressing time is 4h to 6h, for example, it can be 4h, 4.5h, 5h, 5.5h or 6h, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0073] In some embodiments, the pressure of the hot isostatic pressing is 80MPa to 150MPa, for example, it can be 80MPa, 90MPa, 100MPa, 110MPa, 120MPa, 130MPa, 140MPa or 150MPa, but is not limited to the listed values, and other unlisted values within the range are also applicable.
[0074] In some embodiments, the hot isostatic pressing is performed in an argon atmosphere.
[0075] In some embodiments, the solution aging temperature is 480°C to 520°C, for example, 480°C, 490°C, 500°C, 510°C or 520°C, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0076] In some embodiments, the solution aging time is 2h to 5h, for example, it can be 2h, 3h, 4h or 5h, but is not limited to the listed values. Other unlisted values within the range are also applicable.
[0077] This invention utilizes solution aging to induce the precipitation of nanoscale strengthening phases within the alloy, thereby achieving an optimal balance between strength and conductivity. Specifically, during solution aging at 480℃~520℃, supersaturated chromium atoms precipitate from the copper matrix, forming numerous nanoscale dispersed particles. These nanoparticles effectively hinder the movement of dislocations in the crystal, significantly enhancing the alloy's strength and hardness. Furthermore, in the solution state, Cr and Zr dissolved in the copper matrix severely interfere with the directional movement of electrons, leading to a decrease in conductivity. After aging treatment, these atoms precipitate as independent particles, "purifying" the copper matrix, reducing electron scattering, and thus significantly restoring conductivity.
[0078] As a preferred embodiment of the preparation method provided by the present invention, the preparation method includes the following steps:
[0079] S1. Mix the raw materials according to the formula and perform vacuum induction melting at a temperature of 1500℃~1600℃ in a nitrogen atmosphere to obtain an alloy melt; the alloy melt is atomized to obtain micro-alloyed copper powder with an average particle size of 50μm~100μm.
[0080] The microalloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.04wt%~0.6wt%, the mass percentage of Zr is 0.015wt%~0.35wt%, and the balance is copper and unavoidable impurities.
[0081] S2. Mix the polysaccharide solution with the micro-alloyed copper powder, remove the solvent, and obtain the coated micro-alloyed copper powder;
[0082] The solvent for the polysaccharide solution is anhydrous ethanol, and the solute is polysaccharide and organic additives;
[0083] The polysaccharide includes any one or a combination of at least two of starch, cellulose, chitosan or sodium alginate; the organic adjuvant includes any one or a combination of at least two of ascorbic acid, citric acid, polyvinylpyrrolidone or sodium dodecylbenzenesulfonate.
[0084] The amount of the polysaccharide solution used is 50wt%~60wt% of the micro-alloyed copper powder; the amount of the polysaccharide used is 0.2wt%~0.5wt% of the micro-alloyed copper powder; the amount of the organic additive used is 10wt%~15wt% of the micro-alloyed copper powder.
[0085] S3. Sinter the coated microalloyed copper powder in a hydrogen atmosphere to obtain graphene-coated microalloyed copper powder.
[0086] The sintering heating rate is 5℃ / min~10℃ / min, the temperature is 400℃~500℃, the time is 3h~5h, and the absolute pressure is 50mbar~100mbar; after sintering, the furnace is cooled to room temperature.
[0087] The gas used in the hydrogen atmosphere includes a mixture of nitrogen and hydrogen, with a volume ratio of nitrogen to hydrogen of 4:6.
[0088] S4. The graphene-coated microalloyed copper powder is subjected to hot isostatic pressing and solution aging to obtain the microalloyed copper graphene composite material.
[0089] The hot isostatic pressing is carried out in an argon atmosphere, with a heating rate of 5℃ / min~10℃ / min, a temperature of 900℃~1050℃, a time of 4h~6h, and a pressure of 80MPa~150MPa.
[0090] The solution aging temperature is 480℃~520℃, and the time is 2h~5h.
[0091] An embodiment of the present invention provides a microalloyed copper-graphene composite material, which is prepared by the preparation method described in any embodiment.
[0092] Example 1
[0093] This embodiment provides a method for preparing microalloyed copper-graphene composite materials, including the following steps:
[0094] S1. The raw materials are mixed according to the formula and then vacuum induction melting is carried out at a temperature of 1500℃ in a nitrogen atmosphere to obtain an alloy melt; the alloy melt is atomized to obtain micro-alloyed copper powder with an average particle size of 80μm.
[0095] The micro-alloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.3wt%, the mass percentage of Zr is 0.2wt%, and the balance is copper and unavoidable impurities.
[0096] S2. Mix the polysaccharide solution with the micro-alloyed copper powder, remove the solvent, and obtain the coated micro-alloyed copper powder;
[0097] The solvent for the polysaccharide solution is anhydrous ethanol, and the solute is polysaccharide and organic additives;
[0098] The polysaccharide is chitosan (degree of deacetylation 95%, weight-average molecular weight 200,000 Da, sieved through a 200-mesh sieve); the organic additive is ascorbic acid.
[0099] The amount of the polysaccharide solution used is 50 wt% of the microalloyed copper powder; the amount of the polysaccharide used is 0.2 wt% of the microalloyed copper powder; and the amount of the organic additive used is 10 wt% of the microalloyed copper powder.
[0100] S3. Sinter the coated microalloyed copper powder in a hydrogen atmosphere to obtain graphene-coated microalloyed copper powder.
[0101] The sintering process involves a heating rate of 5°C / min, a temperature of 400°C, a time of 3 hours, and an absolute pressure of 50 mbar. After sintering, the furnace is cooled to room temperature.
[0102] The gas used in the hydrogen atmosphere includes a mixture of nitrogen and hydrogen, with a volume ratio of nitrogen to hydrogen of 4:6.
[0103] S4. The graphene-coated microalloyed copper powder is subjected to hot isostatic pressing and solution aging to obtain the microalloyed copper graphene composite material.
[0104] The hot isostatic pressing was carried out in an argon atmosphere, with a heating rate of 5℃ / min, a temperature of 900℃, a time of 4h, and a pressure of 80MPa.
[0105] The solution aging temperature is 480℃ and the time is 2 hours.
[0106] Example 2
[0107] This embodiment provides a method for preparing microalloyed copper-graphene composite materials, including the following steps:
[0108] S1. The raw materials are mixed according to the formula and then vacuum induction melting is carried out at a temperature of 1600℃ in a nitrogen atmosphere to obtain an alloy melt; the alloy melt is atomized to obtain micro-alloyed copper powder with an average particle size of 80μm.
[0109] The micro-alloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.3wt%, the mass percentage of Zr is 0.2wt%, and the balance is copper and unavoidable impurities.
[0110] S2. Mix the polysaccharide solution with the micro-alloyed copper powder, remove the solvent, and obtain the coated micro-alloyed copper powder;
[0111] The solvent for the polysaccharide solution is anhydrous ethanol, and the solute is polysaccharide and organic additives;
[0112] The polysaccharide is chitosan (degree of deacetylation 95%, weight-average molecular weight 200,000 Da, sieved through a 200-mesh sieve); the organic additive is ascorbic acid.
[0113] The amount of the polysaccharide solution used is 60 wt% of the micro-alloyed copper powder; the amount of the polysaccharide used is 0.5 wt% of the micro-alloyed copper powder; and the amount of the organic additive used is 15 wt% of the micro-alloyed copper powder.
[0114] S3. Sinter the coated microalloyed copper powder in a hydrogen atmosphere to obtain graphene-coated microalloyed copper powder.
[0115] The sintering process involves a heating rate of 10°C / min, a temperature of 500°C, a time of 5 hours, and an absolute pressure of 100 mbar. After sintering, the furnace is cooled to room temperature.
[0116] The gas used in the hydrogen atmosphere includes a mixture of nitrogen and hydrogen, with a volume ratio of nitrogen to hydrogen of 4:6.
[0117] S4. The graphene-coated microalloyed copper powder is subjected to hot isostatic pressing and solution aging to obtain the microalloyed copper graphene composite material.
[0118] The hot isostatic pressing was carried out in an argon atmosphere, with a heating rate of 10℃ / min, a temperature of 1050℃, a time of 6h, and a pressure of 150MPa.
[0119] The solution aging temperature is 520℃ and the time is 5 hours.
[0120] Example 3
[0121] This embodiment provides a method for preparing microalloyed copper-graphene composite materials, including the following steps:
[0122] S1. The raw materials are mixed according to the formula and then vacuum induction melting is carried out at a temperature of 1550℃ in a nitrogen atmosphere to obtain an alloy melt; the alloy melt is atomized to obtain micro-alloyed copper powder with an average particle size of 80μm.
[0123] The micro-alloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.3wt%, the mass percentage of Zr is 0.2wt%, and the balance is copper and unavoidable impurities.
[0124] S2. Mix the polysaccharide solution with the micro-alloyed copper powder, remove the solvent, and obtain the coated micro-alloyed copper powder;
[0125] The solvent for the polysaccharide solution is anhydrous ethanol, and the solute is polysaccharide and organic additives;
[0126] The polysaccharide is chitosan (degree of deacetylation 95%, weight-average molecular weight 200,000 Da, sieved through a 200-mesh sieve); the organic additive is ascorbic acid.
[0127] The amount of the polysaccharide solution used is 55 wt% of the micro-alloyed copper powder; the amount of the polysaccharide used is 0.3 wt% of the micro-alloyed copper powder; and the amount of the organic additive used is 12 wt% of the micro-alloyed copper powder.
[0128] S3. Sinter the coated microalloyed copper powder in a hydrogen atmosphere to obtain graphene-coated microalloyed copper powder.
[0129] The sintering process involves a heating rate of 8°C / min, a temperature of 450°C, a time of 4 hours, and an absolute pressure of 80 mbar. After sintering, the furnace is cooled to room temperature.
[0130] The gas used in the hydrogen atmosphere includes a mixture of nitrogen and hydrogen, with a volume ratio of nitrogen to hydrogen of 4:6.
[0131] S4. The graphene-coated microalloyed copper powder is subjected to hot isostatic pressing and solution aging to obtain the microalloyed copper graphene composite material.
[0132] The hot isostatic pressing was carried out in an argon atmosphere, with a heating rate of 8℃ / min, a temperature of 1000℃, a time of 5h, and a pressure of 100MPa.
[0133] The solution aging temperature is 500℃ and the time is 4 hours.
[0134] Example 4
[0135] This embodiment provides a method for preparing microalloyed copper-graphene composite materials, including the following steps:
[0136] S1. The raw materials are mixed according to the formula and then vacuum induction melting is carried out at a temperature of 1600℃ in a nitrogen atmosphere to obtain an alloy melt; the alloy melt is atomized to obtain micro-alloyed copper powder with an average particle size of 80μm.
[0137] The micro-alloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.3wt%, the mass percentage of Zr is 0.2wt%, and the balance is copper and unavoidable impurities.
[0138] S2. Mix the polysaccharide solution with the micro-alloyed copper powder, remove the solvent, and obtain the coated micro-alloyed copper powder;
[0139] The solvent for the polysaccharide solution is anhydrous ethanol, and the solute is polysaccharide and organic additives;
[0140] The polysaccharide is chitosan (degree of deacetylation 95%, weight-average molecular weight 200,000 Da, sieved through a 200-mesh sieve); the organic additive is ascorbic acid.
[0141] The amount of the polysaccharide solution used is 55 wt% of the microalloyed copper powder; the amount of the polysaccharide used is 0.2 wt% of the microalloyed copper powder; and the amount of the organic additive used is 10 wt% of the microalloyed copper powder.
[0142] S3. Sinter the coated microalloyed copper powder in a hydrogen atmosphere to obtain graphene-coated microalloyed copper powder.
[0143] The sintering process involves a heating rate of 10°C / min, a temperature of 500°C, a time of 5 hours, and an absolute pressure of 80 mbar. After sintering, the furnace is cooled to room temperature.
[0144] The gas used in the hydrogen atmosphere includes a mixture of nitrogen and hydrogen, with a volume ratio of nitrogen to hydrogen of 4:6.
[0145] S4. The graphene-coated microalloyed copper powder is subjected to hot isostatic pressing and solution aging to obtain the microalloyed copper graphene composite material.
[0146] The hot isostatic pressing was carried out in an argon atmosphere, with a heating rate of 10℃ / min, a temperature of 1050℃, a time of 5h, and a pressure of 120MPa.
[0147] The solution aging temperature is 490℃ and the time is 5 hours.
[0148] Example 5
[0149] This embodiment provides a method for preparing microalloyed copper-graphene composite materials. Except that instead of using vacuum induction melting and atomization to prepare microalloyed copper powder, the raw materials are directly mechanically ball-milled and cold-welded in a nitrogen atmosphere. All other aspects are the same as in Example 3.
[0150] Example 6
[0151] This embodiment provides a method for preparing microalloyed copper-graphene composite materials. Except for replacing hot isostatic pressing with rapid hot pressing, the rest is the same as in Example 3, including the following steps:
[0152] S1. The raw materials are mixed according to the formula and then vacuum induction melting is carried out at a temperature of 1550℃ in a nitrogen atmosphere to obtain an alloy melt; the alloy melt is atomized to obtain micro-alloyed copper powder with an average particle size of 80μm.
[0153] The micro-alloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.3wt%, the mass percentage of Zr is 0.2wt%, and the balance is copper and unavoidable impurities.
[0154] S2. Mix the polysaccharide solution with the micro-alloyed copper powder, remove the solvent, and obtain the coated micro-alloyed copper powder;
[0155] The solvent for the polysaccharide solution is anhydrous ethanol, and the solute is polysaccharide and organic additives;
[0156] The polysaccharide is chitosan (degree of deacetylation 95%, weight-average molecular weight 200,000 Da, sieved through a 200-mesh sieve); the organic additive is ascorbic acid.
[0157] The amount of the polysaccharide solution used is 55 wt% of the micro-alloyed copper powder; the amount of the polysaccharide used is 0.3 wt% of the micro-alloyed copper powder; and the amount of the organic additive used is 12 wt% of the micro-alloyed copper powder.
[0158] S3. Sinter the coated microalloyed copper powder in a hydrogen atmosphere to obtain graphene-coated microalloyed copper powder.
[0159] The sintering process involves a heating rate of 8°C / min, a temperature of 450°C, a time of 4 hours, and an absolute pressure of 80 mbar. After sintering, the furnace is cooled to room temperature.
[0160] The gas used in the hydrogen atmosphere includes a mixture of nitrogen and hydrogen, with a volume ratio of nitrogen to hydrogen of 4:6.
[0161] S4. The graphene-coated microalloyed copper powder is subjected to rapid hot pressing and solution aging to obtain the microalloyed copper graphene composite material.
[0162] The rapid hot pressing was carried out in an argon atmosphere at a temperature of 1000℃ for 15 minutes and a pressure of 40MPa.
[0163] The solution aging temperature is 500℃ and the time is 4 hours.
[0164] Example 7
[0165] This embodiment provides a method for preparing a microalloyed copper-graphene composite material. Except for the composition of the microalloyed copper powder, which is different from that in Example 3, the rest is the same as in Example 3.
[0166] In this embodiment, the microalloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.04wt%, the mass percentage of Zr is 0.015wt%, and the average particle size is 50μm.
[0167] Example 8
[0168] This embodiment provides a method for preparing a microalloyed copper-graphene composite material. Except for the composition of the microalloyed copper powder, which is different from that in Example 3, the rest is the same as in Example 3.
[0169] In this embodiment, the microalloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.7wt%, the mass percentage of Zr is 0.35wt%, and the average particle size is 100μm.
[0170] Comparative Example 1
[0171] This comparative example provides a method for preparing microalloyed copper material, which is the same as that in Example 3 except that step S2 is not performed, and includes the following steps:
[0172] S1. The raw materials are mixed according to the formula and then vacuum induction melting is carried out at a temperature of 1550℃ in a nitrogen atmosphere to obtain an alloy melt; the alloy melt is atomized to obtain micro-alloyed copper powder with an average particle size of 80μm.
[0173] The micro-alloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.3wt%, the mass percentage of Zr is 0.2wt%, and the balance is copper and unavoidable impurities.
[0174] S3. Sintering the microalloyed copper powder in a hydrogen atmosphere;
[0175] The sintering process involves a heating rate of 8°C / min, a temperature of 450°C, a time of 4 hours, and an absolute pressure of 80 mbar. After sintering, the furnace is cooled to room temperature.
[0176] The gas used in the hydrogen atmosphere includes a mixture of nitrogen and hydrogen, with a volume ratio of nitrogen to hydrogen of 4:6.
[0177] S4. Then, hot isostatic pressing and solution aging are performed to obtain the micro-alloyed copper material.
[0178] The hot isostatic pressing was carried out in an argon atmosphere, with a heating rate of 8℃ / min, a temperature of 1000℃, a time of 5h, and a pressure of 100MPa.
[0179] The solution aging temperature is 500℃ and the time is 4 hours.
[0180] Comparative Example 2
[0181] This comparative example provides a method for preparing a microalloyed copper composite material, which is the same as Example 3 except that it is not sintered in a hydrogen atmosphere (step S3 is omitted), and includes the following steps:
[0182] S1. The raw materials are mixed according to the formula and then vacuum induction melting is carried out at a temperature of 1550℃ in a nitrogen atmosphere to obtain an alloy melt; the alloy melt is atomized to obtain micro-alloyed copper powder with an average particle size of 80μm.
[0183] The micro-alloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.3wt%, the mass percentage of Zr is 0.2wt%, and the balance is copper and unavoidable impurities.
[0184] S2. Mix the polysaccharide solution with the micro-alloyed copper powder, remove the solvent, and obtain the coated micro-alloyed copper powder;
[0185] The solvent for the polysaccharide solution is anhydrous ethanol, and the solute is polysaccharide and organic additives;
[0186] The polysaccharide is chitosan (degree of deacetylation 95%, weight-average molecular weight 200,000 Da, sieved through a 200-mesh sieve); the organic additive is ascorbic acid.
[0187] The amount of the polysaccharide solution used is 55 wt% of the micro-alloyed copper powder; the amount of the polysaccharide used is 0.3 wt% of the micro-alloyed copper powder; and the amount of the organic additive used is 12 wt% of the micro-alloyed copper powder.
[0188] S4. The coated micro-alloyed copper powder is subjected to hot isostatic pressing and solution aging to obtain the micro-alloyed copper composite material.
[0189] The hot isostatic pressing was carried out in an argon atmosphere, with a heating rate of 8℃ / min, a temperature of 1000℃, a time of 5h, and a pressure of 100MPa.
[0190] The solution aging temperature is 500℃ and the time is 4 hours.
[0191] Comparative Example 3
[0192] This comparative example provides a method for preparing a microalloyed copper-graphene composite material, which is the same as that in Example 3 except that solid solution aging is not performed, and includes the following steps:
[0193] S1. The raw materials are mixed according to the formula and then vacuum induction melting is carried out at a temperature of 1550℃ in a nitrogen atmosphere to obtain an alloy melt; the alloy melt is atomized to obtain micro-alloyed copper powder with an average particle size of 80μm.
[0194] The micro-alloyed copper powder is composed of CuCrZr, wherein the mass percentage of Cr is 0.3wt%, the mass percentage of Zr is 0.2wt%, and the balance is copper and unavoidable impurities.
[0195] S2. Mix the polysaccharide solution with the micro-alloyed copper powder, remove the solvent, and obtain the coated micro-alloyed copper powder;
[0196] The solvent for the polysaccharide solution is anhydrous ethanol, and the solute is polysaccharide and organic additives;
[0197] The polysaccharide is chitosan (degree of deacetylation 95%, weight-average molecular weight 200,000 Da, sieved through a 200-mesh sieve); the organic additive is ascorbic acid.
[0198] The amount of the polysaccharide solution used is 55 wt% of the micro-alloyed copper powder; the amount of the polysaccharide used is 0.3 wt% of the micro-alloyed copper powder; and the amount of the organic additive used is 12 wt% of the micro-alloyed copper powder.
[0199] S3. Sinter the coated microalloyed copper powder in a hydrogen atmosphere to obtain graphene-coated microalloyed copper powder.
[0200] The sintering process involves a heating rate of 8°C / min, a temperature of 450°C, a time of 4 hours, and an absolute pressure of 80 mbar. After sintering, the furnace is cooled to room temperature.
[0201] The gas used in the hydrogen atmosphere includes a mixture of nitrogen and hydrogen, with a volume ratio of nitrogen to hydrogen of 4:6.
[0202] S4. The graphene-coated micro-alloyed copper powder is subjected to hot isostatic pressing to obtain the micro-alloyed copper graphene composite material.
[0203] The hot isostatic pressing was carried out in an argon atmosphere, with a heating rate of 8℃ / min, a temperature of 1000℃, a time of 5h, and a pressure of 100MPa.
[0204] Comparative Example 4
[0205] This comparative example provides a method for preparing a microalloyed copper-graphene composite material. Except for replacing polysaccharides with polyvinyl alcohol (weight-average molecular weight 10000 Da) by mass, the rest is the same as in Example 3.
[0206] Comparative Example 5
[0207] This comparative example provides a method for preparing a microalloyed copper-graphene composite material, which is the same as in Example 3 except that the polysaccharide is replaced by sucrose.
[0208] Comparative Example 6
[0209] This comparative example provides a method for preparing a microalloyed copper-graphene composite material, which is the same as in Example 3 except that the polysaccharide is replaced by glucose by mass.
[0210] Performance Characterization
[0211] The tensile strength, elongation, and volume resistivity of the materials obtained in the above embodiments and comparative examples were tested, and the test results are shown in Table 1. The tensile strength and elongation tests were performed according to GB / T228.1-2021 "Metallic materials, tensile testing—Part 1: Tests at room temperature," and the elongation was calculated by measuring the gauge length elongation after the specimen fractured. The electrical conductivity of this graphene-copper composite material is expressed as a percentage of the International Annealed Copper Standard (IACS), calculated using the following formula:
[0212] IACS(%) = (1.72 × 10) -8 (measured volume resistivity) × 100%;
[0213] In the formula, 1.72×10 -8 Ω·m is the international standard resistivity of annealed pure copper.
[0214] Table 1
[0215]
[0216] As can be seen from Examples 1 to 8 in Table 1, the method for preparing microalloyed copper-graphene composite materials provided by the present invention can simultaneously improve the tensile strength, elongation and conductivity of the material. The resulting product has high strength, high plasticity and high conductivity, which can meet the performance requirements of high-density electronic packaging and interconnection.
[0217] A comparison of Comparative Examples 1, 2, and 3 with Example 3 shows that omitting any necessary step leads to a decrease in overall performance. This indicates that omitting polysaccharide coating prevents the in-situ generation of graphene-modified interfaces on the copper powder surface, making it difficult to construct a complete conductive network and mechanically reinforced structure; omitting hydrogen atmosphere sintering prevents the polysaccharide from being controllably converted into highly graphitized, tightly bonded few-layer graphene, thus failing to fully realize its modifying effect; omitting solution aging prevents alloying elements from achieving uniform solution and dispersed precipitation, making it difficult to achieve matrix strengthening, ultimately resulting in a significant decrease in material performance.
[0218] A comparison of Comparative Examples 4, 5, and 6 with Example 3 shows that only by using the polysaccharide specified in this invention as the carbon source can the composite material with the best overall performance be obtained. Replacing it with monosaccharides, oligosaccharides, or other organic polymeric carbon sources of equal mass cannot achieve the same modification effect. This is because small molecule monosaccharides or oligosaccharides undergo violent pyrolysis reactions, easily forming discontinuous carbon layers with weak bonding to the matrix; conventional polymeric carbon sources are difficult to form highly graphitized few-layer graphene, resulting in numerous carbon layer defects; while the polysaccharide used in this invention can form a continuous and dense molecular-level coating layer, and its pyrolysis behavior is gradual and controllable, enabling in-situ conversion into high-quality few-layer graphene, fully leveraging its electrical conductivity and mechanical enhancement advantages to achieve a comprehensive improvement in material performance.
[0219] In summary, this invention utilizes a polysaccharide solution containing polysaccharides to molecularly coat microalloyed copper powder. Due to their longer molecular chains and more repeating monosaccharide units, polysaccharides can form a continuous and dense coating layer on the surface of the microalloyed copper powder. The carbon content per unit mass is significantly higher than that of monosaccharides or oligosaccharides. During sintering in a hydrogen atmosphere, polysaccharides can be in situ transformed into a few-layer graphene or high-quality carbon layer uniformly attached to the surface of the microalloyed copper powder. This effectively avoids problems such as discontinuous carbon layers, uneven thickness, and weak bonding with the microalloyed copper powder matrix that are prone to occur with monosaccharide or oligosaccharide coatings. Subsequently, after hot isostatic pressing and solution aging treatment, the uniformly dispersed few-layer graphene or high-quality carbon layer can fully exert its excellent electrical and thermal conductivity and mechanical strengthening effects, significantly improving the overall performance of the microalloyed copper graphene composite material. This invention facilitates the production of products with uniform composition, tight interfacial bonding, and high density, thereby solving the problems of large performance fluctuations and limited reinforcement effects of composite materials caused by insufficient carbon sources or uneven carbon layer distribution in existing technologies. It can meet the stringent requirements of high-density electronic packaging and interconnection for material performance. The invention uses polysaccharides as a carbon source, which greatly reduces raw material costs and conforms to the concept of green manufacturing. Compared with the violent pyrolysis of small molecule monosaccharides or oligosaccharides, polysaccharides have a smoother and more phased thermal decomposition behavior, which is conducive to precise control of the carbonization process and obtaining graphene coatings with fewer defects and a higher degree of graphitization. The combination of polysaccharides and organic additives in this invention can introduce beneficial heteroatoms during the sintering process. These heteroatoms can modify the electronic structure of graphene and strengthen interfacial bonding through interaction with copper.
[0220] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.
Claims
1. A method for preparing a microalloyed copper-graphene composite material, characterized in that, The preparation method includes the following steps: A polysaccharide solution is mixed with microalloyed copper powder, and the solvent is removed to obtain coated microalloyed copper powder; the coated microalloyed copper powder is sintered in a hydrogen atmosphere to obtain graphene-coated microalloyed copper powder; the graphene-coated microalloyed copper powder is subjected to hot isostatic pressing and solution aging to obtain the microalloyed copper-graphene composite material. The solute in the polysaccharide solution includes polysaccharide and organic additives, wherein the polysaccharide has ≥10 carbon atoms.
2. The preparation method according to claim 1, characterized in that, The polysaccharide includes any one or a combination of at least two of starch, cellulose, chitosan or sodium alginate; And / or, the organic adjuvant includes any one or a combination of at least two of ascorbic acid, citric acid, polyvinylpyrrolidone, or sodium dodecylbenzenesulfonate.
3. The preparation method according to claim 1 or 2, characterized in that, The amount of the polysaccharide solution used is 50wt%~60wt% of the microalloyed copper powder; And / or, the amount of the polysaccharide used is 0.2wt%~0.5wt% of the microalloyed copper powder; And / or, the amount of the organic additive is 10wt% to 15wt% of the microalloyed copper powder.
4. The preparation method according to any one of claims 1 to 3, characterized in that, The average particle size of the micro-alloyed copper powder is 50μm~100μm; And / or, the composition of the microalloyed copper powder is CuCrZr, wherein the mass percentage of Cr is 0.04wt%~0.7wt% and the mass percentage of Zr is 0.015wt%~0.35wt%.
5. The preparation method according to any one of claims 1 to 4, characterized in that, The heating rate for sintering is 5℃ / min to 10℃ / min; And / or, the sintering temperature is 400℃~500℃; And / or, the sintering time is 3h~5h; And / or, the absolute pressure of the sintering is 50 mbar to 100 mbar.
6. The preparation method according to any one of claims 1 to 5, characterized in that, The gas used in the hydrogen atmosphere includes a mixture of nitrogen and hydrogen; In the nitrogen and hydrogen mixture, the volume percentage of hydrogen is not less than 60 vol.
7. The preparation method according to any one of claims 1 to 6, characterized in that, The heating rate of the hot isostatic pressing is 5℃ / min~10℃ / min; And / or, the temperature of the hot isostatic pressing is 900℃~1050℃; And / or, the hot isostatic pressing time is 4h~6h; And / or, the pressure of the hot isostatic pressing is 80MPa~150MPa.
8. The preparation method according to any one of claims 1 to 7, characterized in that, The hot isostatic pressing is carried out in an argon atmosphere.
9. The preparation method according to any one of claims 1 to 8, characterized in that, The solution aging temperature is 480℃~520℃; And / or, the solution aging time is 2h to 5h.
10. A microalloyed copper-graphene composite material, characterized in that, The microalloyed copper graphene composite material is prepared by the preparation method described in any one of claims 1 to 9.