Metal ceramic composite material, preparation method, vehicle and electronic equipment

Abstract

The embodiment of the invention provides a metal ceramic composite material, a preparation method, a vehicle and electronic equipment, the metal ceramic composite material comprises a metal matrix, ceramic particles of a first fractal dimension and ceramic particles of a second fractal dimension, and the first fractal dimension is greater than the second fractal dimension. Through cooperative use of ceramic particles with different fractal dimensions, balance can be obtained between processing performance and material performance, the ceramic particles with simple morphology have better fluidity in extrusion, rolling and other processing technologies, and resistance and nonuniformity in the processing process are reduced, so that the forming rate is increased, and the production cost is reduced. The ceramic particles with complex morphology can provide better interface bonding and enhancing effects, the mechanical property of the composite material can be improved, the reasonable particle morphology combination can reduce processing defects, and the consistency and quality of products are improved.

Description

Technical Field

[0001] This application relates to the field of materials technology, and in particular to a metal-ceramic composite material and its preparation method, as well as vehicles and electronic devices. Background Technology

[0002] Metal-ceramic composites are composite materials consisting of a metal matrix and a ceramic reinforcement. They combine the advantages of both metals and ceramics, such as high hardness, high strength, corrosion resistance, wear resistance, and a small coefficient of thermal expansion. They have a wide range of applications, such as in various vehicle components.

[0003] Currently, research mainly focuses on the composition, content, and particle size of metal-ceramic composites in order to improve their performance.

[0004] However, the inventors discovered through research that the morphology of ceramic materials has a significant impact on the mechanical properties of composite materials and the sample molding rate. Summary of the Invention

[0005] This application provides metal-ceramic composite materials and their preparation methods, as well as vehicles and electronic devices, to improve the mechanical properties and molding yield of the composite materials.

[0006] In a first aspect, embodiments of this application provide a metal-ceramic composite material, comprising:

[0007] A metallic matrix, ceramic particles with a first fractal dimension and ceramic particles with a second fractal dimension; the first fractal dimension is greater than the second fractal dimension.

[0008] In one possible implementation, the volume percentage of the metal matrix is ​​60%-95%, and the volume percentages of the ceramic particles of the first fractal dimension and the ceramic particles of the second fractal dimension are 5%-40%.

[0009] In one possible implementation, the metal matrix includes an aluminum matrix, a copper matrix, a titanium matrix, or a magnesium matrix.

[0010] In one possible implementation, the metal substrate includes an aluminum substrate, which comprises silicon, magnesium, and aluminum.

[0011] In the aluminum matrix, the mass percentage of silicon is 0.01%-6%, and the mass percentage of magnesium is 0.02%-5%.

[0012] In one possible implementation, the ceramic particles include at least one of silicon carbide particles, alumina particles, tungsten particles, and boron particles.

[0013] In one possible implementation, the first fractal dimension is 2-3, and the second fractal dimension is 1-2.

[0014] In one possible implementation, the volume percentage of the ceramic particles with the first fractal dimension is 50%-90%, and the volume percentage of the ceramic particles with the second fractal dimension is 10%-50%.

[0015] In one possible implementation, the particle size of the ceramic particles with the first fractal dimension and the ceramic particles with the second fractal dimension, and their volume percentages, satisfy the following relationship:

[0016]

[0017] Where ds represents the particle size of ceramic particles with the first fractal dimension and ceramic particles with the second fractal dimension, and Vs represents the volume percentage of ceramic particles with the first fractal dimension and ceramic particles with the second fractal dimension.

[0018] In one possible implementation, the particle size of the ceramic particles with the first fractal dimension and the ceramic particles with the second fractal dimension is 0.05 μm-20 μm.

[0019] Secondly, embodiments of this application provide a method for preparing the metal-ceramic composite material described in the first aspect, characterized in that the method includes:

[0020] The metal matrix, ceramic particles of the first fractal dimension and ceramic particles of the second fractal dimension are mixed and pressed into shape to obtain a green body.

[0021] The green blank is subjected to hot forging, extrusion and rolling to obtain the metal-ceramic composite material.

[0022] In one possible implementation, the pressing pressure is 50MPa-200MPa, and the holding time is 1min-60min.

[0023] In one possible implementation, the sintering heating rate of the hot forging is 1℃ / min-15℃ / min, the sintering temperature is 400℃-650℃, the holding time is 1h-6h, the pressure is 50MPa-300MPa, and the holding time is 1min-60min.

[0024] In one possible implementation, the extrusion ratio is 5-30, and the heating temperature is 400℃-600℃.

[0025] In one possible implementation, the heating temperature for rolling is 400°C-600°C.

[0026] Thirdly, embodiments of this application provide a vehicle comprising the metal-ceramic composite material described in the first aspect.

[0027] Fourthly, embodiments of this application provide an electronic device comprising the metal-ceramic composite material described in the first aspect.

[0028] The metal-ceramic composite material and its preparation method, as well as the vehicle and electronic equipment provided in this application, include a metal matrix, ceramic particles with a first fractal dimension and ceramic particles with a second fractal dimension, wherein the first fractal dimension is greater than the second fractal dimension. By using ceramic particles with different fractal dimensions in combination, that is, by using ceramic particles with different morphologies in combination, a balance can be achieved between processing performance and material properties. Ceramic particles with simple morphologies have better flowability in processing processes such as extrusion and rolling, reducing resistance and inhomogeneity during processing, thereby improving the molding rate. Ceramic particles with complex morphologies can provide better interfacial bonding and reinforcement effects, which can improve the mechanical properties of the composite material. A reasonable combination of particle morphologies can reduce processing defects and improve product consistency and quality. Detailed Implementation

[0029] Exemplary embodiments will be described in detail below. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0030] Metal-ceramic composites are composite materials composed of a metal matrix and a ceramic reinforcement. The metal matrix provides the material with ductility, toughness, and thermal conductivity, while the ceramic reinforcement provides hardness, wear resistance, and high-temperature resistance. This gives metal-ceramic composites the advantages of both metals and ceramics, such as high hardness, high strength, corrosion resistance, wear resistance, and a low coefficient of thermal expansion. Metal-ceramic composites have a wide range of applications, including vehicle braking systems, engine components, transmission systems, body structures, and thermal management systems. For example, they can be used in brake pads and calipers in braking systems, pistons, cylinder liners, and turbochargers in engine components, gears and bearings in transmission systems, and radiators in thermal management systems. They can also be used in electronic devices, including mobile phones (including flip phones, traditional phones, and smartphones), tablets, laptops, PDAs, and smart bracelets. For example, metal-ceramic composites can be used in battery compartments, back covers, and lens covers. Currently, research focuses on the composition, content, and particle size of metal-ceramic composites to achieve advantages such as high elastic modulus, high strength, high elongation, low density, and high thermal conductivity.

[0031] The primary form of ceramic reinforcement is ceramic particles. The inventors discovered that the morphology of ceramic particles significantly impacts the mechanical properties and sample molding rate of composite materials. Inappropriate morphologies can lead to uneven distribution of ceramic particles within the composite material or a lower strengthening effect on the metal matrix, thus affecting the physical and mechanical properties of the composite. Furthermore, ceramic particles with complex morphologies can increase dislocation motion resistance in composite materials, thereby improving their mechanical properties. The combined use of simple and complex morphologies is beneficial for subsequent extrusion and rolling processes, thereby increasing the sample molding rate. Moreover, considering that the morphology of ceramic particles can be characterized by fractal dimension—that is, the fractal dimension can characterize the complexity and irregularity of ceramic particles—different morphologies of ceramic particles have different fractal dimensions. The simpler the morphology (lower irregularity and complexity), the smaller the fractal dimension; the more complex the morphology (higher irregularity and complexity), the larger the fractal dimension.

[0032] Therefore, this application provides a metal-ceramic composite material, comprising a metal matrix, ceramic particles with a first fractal dimension, and ceramic particles with a second fractal dimension, wherein the first fractal dimension is greater than the second fractal dimension. By using ceramic particles with different fractal dimensions, i.e., by using ceramic particles with different morphologies, a balance can be achieved between processing performance and material properties. Ceramic particles with simple morphologies have better flowability in processing processes such as extrusion and rolling, reducing resistance and inhomogeneity during processing, thereby improving the molding rate. Ceramic particles with complex morphologies can provide better interfacial bonding and reinforcement effects, improving the mechanical properties of the composite material. A reasonable combination of particle morphologies can reduce processing defects and improve product consistency and quality.

[0033] For example, the metal matrix, ceramic particles of the first fractal dimension, and ceramic particles of the second fractal dimension can be powder materials, which facilitates subsequent processing.

[0034] In some embodiments, in the metal-ceramic composite material, the volume percentage of the metal matrix is ​​60%-95%, and the volume percentage of ceramic particles with the first fractal dimension and ceramic particles with the second fractal dimension is 5%-40%. The volume percentage of the metal matrix refers to the proportion of the metal matrix in the metal-ceramic composite material, and the volume percentage of ceramic particles with the first fractal dimension and ceramic particles with the second fractal dimension refers to the proportion of the ceramic particles with the first fractal dimension and ceramic particles with the second fractal dimension in the metal-ceramic composite material.

[0035] A high volume percentage of ceramic particles reduces the toughness and ductility of cermet composites, making molding difficult. Conversely, a low volume percentage negatively impacts the composite's performance. By setting the appropriate volume percentage, the molding yield of cermet composites can be improved. This also facilitates uniform distribution of ceramic particles during the batching process, reduces particle agglomeration, enhances the mechanical properties of the composite, and minimizes product defects.

[0036] It should be noted that the sum of the volume percentage of the metal matrix and the volume percentage of the ceramic particles is 1. Here, the volume percentage of the ceramic particles refers to the volume percentage of the ceramic particles in the first fractal dimension and the ceramic particles in the second fractal dimension. For example, the volume percentage of the metal matrix is ​​60%, and the volume percentage of the ceramic particles is 40%.

[0037] For example, the volume percentage of the metal matrix can be a range of 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or any combination thereof.

[0038] The volume percentage of ceramic particles can be 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, or any combination thereof.

[0039] In some embodiments, the metal matrix may include an aluminum matrix, a copper matrix, a titanium matrix, or a magnesium matrix. Aluminum matrices are lightweight, corrosion-resistant, have good thermal and electrical conductivity, and are easy to process and form, making them suitable for various manufacturing processes, such as the automotive and aerospace industries. Copper matrices have good electrical and thermal conductivity and antibacterial properties, making them suitable for applications requiring high-efficiency heat transfer, such as radiators and heat exchangers. Titanium matrices have a high strength-to-weight ratio, corrosion resistance, and biocompatibility, making them suitable for high-performance applications, such as aerospace. Magnesium matrices are lightweight, have good strength and rigidity, and provide shock absorption, making them suitable for lightweight applications, such as portable electronic devices and automotive components.

[0040] In some embodiments, the metal matrix includes an aluminum matrix comprising silicon, magnesium, and aluminum, and may also include other elements. In the aluminum matrix, the mass percentage of silicon is 0.01%-6%, and the mass percentage of magnesium is 0.02%-5%. By simultaneously adding silicon and magnesium, the strength, hardness, and wear resistance of the aluminum alloy can be improved while maintaining good casting properties and machinability. Furthermore, the aforementioned mass percentage settings can further enhance the performance of the aluminum alloy.

[0041] For example, the mass percentage of silicon can be a range of 0.01%, 0.05%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, or any combination thereof.

[0042] The mass percentage of magnesium can be a range of 0.02%, 0.05%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, or any combination thereof.

[0043] In some embodiments, the ceramic particles may include at least one of silicon carbide particles, alumina particles, tungsten particles, and boron particles. Silicon carbide particles have advantages such as high strength, wear resistance, high thermal conductivity, low density, and chemical stability; alumina particles have advantages such as high hardness, high strength, corrosion resistance, electrical insulation, and thermal stability; tungsten particles have advantages such as high density, high melting point, and wear resistance; and boron particles have advantages such as lightweight, high strength, and high hardness. In practical applications, the type of ceramic particles can be selected according to specific application requirements.

[0044] In some embodiments, the first fractal dimension can be greater than or equal to 2, and the second fractal dimension can be less than or equal to 2. For example, the first fractal dimension is 2-3, and the second fractal dimension is 1-2. A larger fractal dimension results in a more complex morphology of the ceramic particles, which are correspondingly sharper and more difficult to process in extrusion, rolling, and other processes. Conversely, a smaller fractal dimension results in a simpler morphology of the ceramic particles, which are correspondingly more rounded and affect the mechanical properties of the composite material. By setting the fractal dimension within the aforementioned range, the mechanical properties of the composite material can be improved while simplifying the processing.

[0045] For example, the first fractal dimension can be a range of 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, or any two of them.

[0046] The second fractal dimension can be a range consisting of 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, or any two of these.

[0047] In some embodiments, the volume percentage of ceramic particles with a first fractal dimension and ceramic particles with a second fractal dimension is 50%-90% and 10%-90% respectively. For example, the volume percentage of ceramic particles with a first fractal dimension is 80% and the volume percentage of ceramic particles with a second fractal dimension is 20%. The first fractal dimension being greater than the second fractal dimension improves the mechanical properties of the composite material. By ensuring a higher proportion of ceramic particles with a first fractal dimension than those with a second fractal dimension, the mechanical properties of the composite material are guaranteed, while simultaneously simplifying the processing difficulty.

[0048] For example, the volume percentage of ceramic particles of the first fractal dimension can be a range of 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or any combination thereof.

[0049] The volume percentage of ceramic particles with the second fractal dimension can be a range of 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, or any combination thereof.

[0050] In some embodiments, the particle size of the ceramic particles with the first fractal dimension and the ceramic particles with the second fractal dimension, and their volume percentages, satisfy the following relationship:

[0051]

[0052] Where ds represents the particle size of ceramic particles with the first fractal dimension and ceramic particles with the second fractal dimension, and Vs represents the volume percentage of ceramic particles with the first fractal dimension and ceramic particles with the second fractal dimension.

[0053] Ceramic particles of the first fractal dimension and ceramic particles of the second fractal dimension can have the same particle size range. The volume percentage of ceramic particles of the first fractal dimension and ceramic particles of the second fractal dimension refers to the proportion of the volume of ceramic particles of the first fractal dimension and ceramic particles of the second fractal dimension in the metal composite material. When the particle size and volume percentage of ceramic particles in the metal-ceramic composite material satisfy the above relationship, the uniformity of ceramic particles in the composite material can be improved.

[0054] For example, taking the uniform distribution of ceramic particles in a matrix form in a metal-ceramic composite as an example, assuming that the ceramic particles are spherical, the spacing between ceramic particles is λ, the particle size (the particle size of ceramic particles in the first fractal dimension and the particle size of ceramic particles in the second fractal dimension) is ds, and the volume percentage of ceramic particles (the volume percentage of ceramic particles in the first fractal dimension and the volume percentage of ceramic particles in the second fractal dimension) is Vs, the volume percentage of uniformly distributed ceramic particles in the composite material has the following relationship (1):

[0055]

[0056] Transforming relation (1), we obtain the following relation (2):

[0057]

[0058] Then, substituting the ceramic particle size ds and the ceramic particle volume percentage Vs into the equation, we can obtain the following relationship (3):

[0059]

[0060] Therefore, when the particle size of the ceramic particles of the first fractal dimension and the ceramic particles of the second fractal dimension satisfy the following relationship (3), the uniform distribution of ceramic particles in the composite material can be improved.

[0061] In some examples, the particle size of the ceramic particles with the first fractal dimension and the ceramic particles with the second fractal dimension can be 0.05 μm to 20 μm. By setting the particle size as described above, the uniform distribution of ceramic particles in the composite material can be improved, the agglomeration of ceramic particles in the composite material can be reduced, the mechanical properties of the composite material can be improved, and product defects can be reduced.

[0062] For example, the particle size of the ceramic particles of the first fractal dimension and the ceramic particles of the second fractal dimension can be a range of 0.05 μm, 1 μm, 3 μm, 5 μm, 7 μm, 9 μm, 10 μm, 13 μm, 15 μm, 17 μm, 18 μm, 20 μm or any combination thereof.

[0063] This application also provides a method for preparing a metal-ceramic composite material, which may include the following steps:

[0064] A metal matrix, ceramic particles with the first fractal dimension, and ceramic particles with the second fractal dimension are mixed and pressed into shape to obtain a green body.

[0065] The green blank is hot forged, extruded and rolled to obtain a metal-ceramic composite material.

[0066] Compression molding can be a process of mixing metal powder, ceramic powder with a first fractal dimension, and ceramic powder with a second fractal dimension, and then compressing them into a solid part with a specific shape and density. A green body refers to a preliminary solid structure formed after compression molding, but without sintering or other treatments.

[0067] In some embodiments, the compression molding pressure is 50 MPa-200 MPa, and the holding time is 1 min-60 min. Higher compression molding pressure generally increases the density and strength of the green body; however, reaching the pressure limit may lead to particle breakage or introduce internal defects such as cracks. Longer holding times generally reduce internal pressure and increase density; however, excessively long holding times may cause excessive flow or decomposition of the binder, affecting the bonding effect. Therefore, when the pressure and holding time are within the above ranges, the quality of the green body can be improved and defects reduced.

[0068] For example, the compression molding pressure can be a range of 50 MPa, 70 MPa, 90 MPa, 100 MPa, 120 MPa, 140 MPa, 150 MPa, 170 MPa, 190 MPa, 200 MPa, or any combination thereof.

[0069] The holding time for compression molding can be a range of 1 min, 5 min, 10 min, 15 min, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, or any combination thereof.

[0070] It should be noted that hot forging refers to applying pressure to a green billet at high temperature to cause it to plastically deform and obtain the desired shape and size.

[0071] In some embodiments, the sintering heating rate of hot forging can be 1°C / min-15°C / min, the sintering temperature is 400°C-650°C, the holding time is 1h-6h, the pressure is 50MPa-300MPa, and the holding time is 1min-60min. This sintering heating rate, sintering temperature, and holding time help promote the diffusion and bonding between powder particles, forming a dense solid structure; this hot forging pressure and holding time help improve the contact and bonding between particles, increasing the density and strength of the composite material.

[0072] For example, the sintering heating rate can be a range of 1℃ / min, 2℃ / min, 4℃ / min, 5℃ / min, 7℃ / min, 9℃ / min, 10℃ / min, 12℃ / min, 14℃ / min, 15℃ / min, or any combination thereof.

[0073] The sintering temperature can be a range of 400℃, 420℃, 450℃, 470℃, 490℃, 500℃, 530℃ / min, 550℃, 570℃, 600℃, 620℃, 650℃ or any combination thereof.

[0074] The holding time for hot forging can be 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h, 5.5h, 6h, or any combination thereof.

[0075] The pressure for hot forging can be a range of 50MPa, 70MPa, 90MPa, 120MPa, 140MPa, 150MPa, 170MPa, 190MPa, 200MPa, 230MPa, 250MPa, 270MPa, 300MPa, or any combination thereof.

[0076] The holding time for hot forging can be a range of 1 min, 5 min, 10 min, 15 min, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, or any combination thereof.

[0077] It should be noted that extrusion is the process of passing material through a die to form a product with a specific cross-sectional shape.

[0078] In some embodiments, the extrusion ratio of the extrusion process is 5-30, and the heating temperature is 400℃-600℃. A larger extrusion ratio can increase the density of the material and improve its mechanical properties, but it requires higher energy input to overcome the material's deformation resistance, increasing production costs and equipment wear. By setting the extrusion ratio as described above, better production efficiency and product quality can be achieved, and by setting the heating temperature as described above, the material can be melted to meet the extrusion requirements.

[0079] For example, the extrusion ratio can be a range of 5, 7, 9, 11, 14, 16, 18, 20, 22, 25, 27, 30 or any two of these.

[0080] The heating temperature for the extrusion process can be a range of 400℃, 420℃, 450℃, 470℃, 490℃, 500℃, 530℃ / min, 550℃, 570℃, 600℃, or any combination thereof.

[0081] It should be noted that rolling is a process in which a metal billet is passed through a pair of rotating rolls to reduce its thickness and change its cross-sectional shape. For example, metal-ceramic composite materials with a thickness of 0.01 mm to 5 mm can be formed by rolling.

[0082] In some embodiments, the rolling heating temperature is 400°C-600°C, which meets the melting temperature of the material, reduces the rolling force required during the rolling process, and reduces energy consumption and equipment wear.

[0083] For example, the heating temperature of the rolling process can be a range of 400°C, 420°C, 450°C, 470°C, 490°C, 500°C, 530°C / min, 550°C, 570°C, 600°C, or any combination thereof.

[0084] This application also provides a vehicle comprising the aforementioned metal-ceramic composite material.

[0085] For example, metal-ceramic composite materials can be used in vehicle braking systems, engine components, transmission systems, body structures, thermal management systems, etc. For instance, they can be used for brake pads and brake linings in braking systems, pistons, cylinder liners, and turbochargers in engine components, gears and bearings in transmission systems, and radiators in thermal management systems.

[0086] This application also provides an electronic device comprising the aforementioned metal-ceramic composite material.

[0087] For example, electronic devices may include mobile phones (including foldable phones, traditional phones, and smartphones), tablets, laptops, PDAs, smart bracelets, and other terminals. For instance, metal-ceramic composite materials can be used in the terminal's battery compartment, back cover, lens cover, etc.

[0088] The following will provide a detailed description of the metal-ceramic composite material, its preparation method, and its application provided by the present invention through specific embodiments.

[0089] Unless otherwise specified, the reagents, materials and instruments used in the following examples are all conventional reagents, materials and instruments in the art, and can be obtained commercially. The reagents involved can also be synthesized by conventional methods in the art.

[0090] Example 1

[0091] a. Weigh the raw material powder (aluminum alloy powder and silicon carbide powder) according to the volume ratio of aluminum alloy powder and silicon carbide powder of 4:1. The silicon carbide powder has a particle size of 0.5μm and includes silicon carbide powder with a first fractal dimension and silicon carbide powder with a second fractal dimension. The volume percentage of silicon carbide powder with the first fractal dimension and silicon carbide powder with the second fractal dimension is 50% each. The first fractal dimension is 2.5 and the second fractal dimension is 1.6.

[0092] b. Place all the powders from step a into a ball mill jar, introduce argon gas, and ball mill using zirconia beads for 20 hours;

[0093] c. Spread the ball-milled parts from step b into a mold, place it on a hydraulic press platform and press it into a green blank. The pressure of the hydraulic press is 100MPa and the holding time is 3min.

[0094] d. Transfer the mold along with the green blank to an atmosphere sintering furnace and sinter at 600℃ for 3-5 hours. Then cool it to 500℃-550℃ and transfer it to a hot press in an argon atmosphere for densification. The pressure of the hot press is 150MPa and the pressure is held for 2 minutes. Then cool it to room temperature in an argon atmosphere.

[0095] e. Remove the blank and heat it to 550°C, then extrude it into the first thin sheet;

[0096] f. The first sheet is heated to 500°C and rolled in multiple passes to finally roll it into a sheet with a thickness of 0.02 mm;

[0097] g. Room temperature tensile properties of the sheet obtained according to test procedure f of national standard GB / T 228.1-2021.

[0098] Example 2

[0099] a. Weigh the raw material powder (aluminum alloy powder and silicon carbide powder) according to the volume ratio of aluminum alloy powder and silicon carbide powder of 4:1. The silicon carbide powder has a particle size of 0.5μm and includes silicon carbide powder with a first fractal dimension and silicon carbide powder with a second fractal dimension. The volume percentage of silicon carbide powder with the first fractal dimension is 60% and the volume percentage of silicon carbide powder with the second fractal dimension is 40%. The first fractal dimension is 2.5 and the second fractal dimension is 1.6.

[0100] b. Place all the powders from step a into a ball mill jar, introduce argon gas, and ball mill using zirconia beads for 20 hours;

[0101] c. Spread the ball-milled parts from step b into a mold, place it on a hydraulic press platform and press it into a green blank. The pressure of the hydraulic press is 100MPa and the holding time is 3min.

[0102] d. Transfer the mold along with the green blank to an atmosphere sintering furnace and sinter at 600℃ for 3-5 hours. Then cool it to 500℃-550℃ and transfer it to a hot press in an argon atmosphere for densification. The pressure of the hot press is 150MPa and the pressure is held for 2 minutes. Then cool it to room temperature in an argon atmosphere.

[0103] e. Remove the blank and heat it to 550°C, then extrude it into the first thin sheet;

[0104] f. The first sheet is heated to 500°C and rolled in multiple passes to finally roll it into a sheet with a thickness of 0.02 mm;

[0105] g. Room temperature tensile properties of the sheet obtained according to test procedure f of national standard GB / T 228.1-2021.

[0106] Example 3

[0107] a. Weigh the raw material powder (aluminum alloy powder and silicon carbide powder) according to the volume ratio of aluminum alloy powder and silicon carbide powder of 4:1. The silicon carbide powder has a particle size of 0.5μm and includes silicon carbide powder with a first fractal dimension and silicon carbide powder with a second fractal dimension. The volume percentage of silicon carbide powder with the first fractal dimension is 80% and the volume percentage of silicon carbide powder with the second fractal dimension is 20%. The first fractal dimension is 2.5 and the second fractal dimension is 1.6.

[0108] b. Place all the powders from step a into a ball mill jar, introduce argon gas, and ball mill using zirconia beads for 20 hours;

[0109] c. Spread the ball-milled parts from step b into a mold, place it on a hydraulic press platform and press it into a green blank. The pressure of the hydraulic press is 100MPa and the holding time is 3min.

[0110] d. Transfer the mold along with the green blank to an atmosphere sintering furnace and sinter at 600℃ for 3-5 hours. Then cool it to 500℃-550℃ and transfer it to a hot press in an argon atmosphere for densification. The pressure of the hot press is 150MPa and the pressure is held for 2 minutes. Then cool it to room temperature in an argon atmosphere.

[0111] e. Remove the blank and heat it to 550°C, then extrude it into the first thin sheet;

[0112] f. The first sheet is heated to 500°C and rolled in multiple passes to finally roll it into a sheet with a thickness of 0.02 mm;

[0113] g. Room temperature tensile properties of the sheet obtained according to test procedure f of national standard GB / T 228.1-2021.

[0114] Example 4

[0115] a. Weigh the raw material powder (aluminum alloy powder and silicon carbide powder) according to the volume ratio of aluminum alloy powder and silicon carbide powder of 4:1. The silicon carbide powder has a particle size of 0.5μm and includes silicon carbide powder with a first fractal dimension and silicon carbide powder with a second fractal dimension. The volume percentage of silicon carbide powder with the first fractal dimension is 90% and the volume percentage of silicon carbide powder with the second fractal dimension is 10%. The first fractal dimension is 2.5 and the second fractal dimension is 1.6.

[0116] b. Place all the powders from step a into a ball mill jar, introduce argon gas, and ball mill using zirconia beads for 20 hours;

[0117] c. Spread the ball-milled parts from step b into a mold, place it on a hydraulic press platform and press it into a green blank. The pressure of the hydraulic press is 100MPa and the holding time is 3min.

[0118] d. Transfer the mold along with the green blank to an atmosphere sintering furnace and sinter at 600℃ for 3-5 hours. Then cool it to 500℃-550℃ and transfer it to a hot press in an argon atmosphere for densification. The pressure of the hot press is 150MPa and the pressure is held for 2 minutes. Then cool it to room temperature in an argon atmosphere.

[0119] e. Remove the blank and heat it to 550°C, then extrude it into the first thin sheet;

[0120] f. The first sheet is heated to 500°C and rolled in multiple passes to finally roll it into a sheet with a thickness of 0.02 mm;

[0121] g. Room temperature tensile properties of the sheet obtained according to test procedure f of national standard GB / T 228.1-2021.

[0122] Comparative Example 1

[0123] a. Weigh the raw material powder (aluminum alloy powder and silicon carbide powder) according to the volume ratio of aluminum alloy powder and silicon carbide powder of 4:1, wherein the particle size of silicon carbide powder is 0.5μm, and all silicon carbide powder is silicon carbide powder with the first fractal dimension, wherein the first fractal dimension is 2.5.

[0124] b. Place all the powders from step a into a ball mill jar, introduce argon gas, and ball mill using zirconia beads for 20 hours;

[0125] c. Spread the ball-milled parts from step b into a mold, place it on a hydraulic press platform and press it into a green blank. The pressure of the hydraulic press is 100MPa and the holding time is 3min.

[0126] d. Transfer the mold along with the green blank to an atmosphere sintering furnace and sinter at 600℃ for 3-5 hours. Then cool it to 500℃-550℃ and transfer it to a hot press in an argon atmosphere for densification. The pressure of the hot press is 150MPa and the pressure is held for 2 minutes. Then cool it to room temperature in an argon atmosphere.

[0127] e. Remove the blank and heat it to 550°C, then extrude it into the first thin sheet;

[0128] f. The first sheet is heated to 500°C and rolled in multiple passes to finally roll it into a sheet with a thickness of 0.02 mm;

[0129] g. Room temperature tensile properties of the sheet obtained according to test procedure f of national standard GB / T 228.1-2021.

[0130] Comparative Example 2

[0131] a. Weigh the raw material powder (aluminum alloy powder and silicon carbide powder) according to the volume ratio of aluminum alloy powder and silicon carbide powder of 4:1, wherein the particle size of silicon carbide powder is 0.5μm, and all silicon carbide powder is silicon carbide powder with the second fractal dimension, wherein the second fractal dimension is 1.6.

[0132] b. Place all the powders from step a into a ball mill jar, introduce argon gas, and ball mill using zirconia beads for 20 hours;

[0133] c. Spread the ball-milled parts from step b into a mold, place it on a hydraulic press platform and press it into a green blank. The pressure of the hydraulic press is 100MPa and the holding time is 3min.

[0134] d. Transfer the mold along with the green blank to an atmosphere sintering furnace and sinter at 600℃ for 3-5 hours. Then cool it to 500℃-550℃ and transfer it to a hot press in an argon atmosphere for densification. The pressure of the hot press is 150MPa and the pressure is held for 2 minutes. Then cool it to room temperature in an argon atmosphere.

[0135] e. Remove the blank and heat it to 550°C, then extrude it into the first thin sheet;

[0136] f. The first sheet is heated to 500°C and rolled in multiple passes to finally roll it into a sheet with a thickness of 0.02 mm;

[0137] g. Room temperature tensile properties of the sheet obtained according to test procedure f of national standard GB / T 228.1-2021.

[0138] In the above embodiments and comparative examples, only the type of silicon carbide powder is different. In Example 1, the silicon carbide powder includes 50% silicon carbide powder with the first fractal dimension and 50% silicon carbide powder with the second fractal dimension. In Example 2, the silicon carbide powder includes 60% silicon carbide powder with the first fractal dimension and 40% silicon carbide powder with the second fractal dimension. In Example 3, the silicon carbide powder includes 80% silicon carbide powder with the first fractal dimension and 20% silicon carbide powder with the second fractal dimension. In Example 4, the silicon carbide powder includes 90% silicon carbide powder with the first fractal dimension and 10% silicon carbide powder with the second fractal dimension. In Comparative Example 1, all the silicon carbide powder is silicon carbide powder with the first fractal dimension. In Comparative Example 2, all the silicon carbide powder is silicon carbide powder with the second fractal dimension.

[0139] The tensile strength and molding properties of the metal-ceramic composite materials used in each embodiment and comparative example were tested, and the test results are shown in Table 1.

[0140] 1. Tensile strength test

[0141] The tensile strength of the metal-ceramic composite materials formed in each embodiment and comparative example was tested using a universal testing machine.

[0142] 2. Molding condition test

[0143] 1) X-ray detection

[0144] X-rays are used to detect internal defects and density changes in composite materials.

[0145] 2) Mechanical performance testing

[0146] Tensile, compression and bending tests.

[0147] Table 1

[0148]

[0149] As can be seen from Examples 1-4, the combined use of silicon carbide powder with the first fractal dimension and silicon carbide powder with the second fractal dimension makes the composite material easier to process and mold, and significantly improves its mechanical properties. In Comparative Example 1, all silicon carbide used was silicon carbide powder with the first fractal dimension, which has a strong ability to hinder dislocation movement, but the silicon carbide morphology is more complex, leading to difficult processing and molding. In Comparative Example 2, all silicon carbide used was silicon carbide powder with the second fractal dimension, which has a simpler morphology and is easier to process and mold, but its ability to hinder dislocation movement is weaker, so the improvement in mechanical properties is limited.

[0150] In the above example, the fractal dimension can be calculated using the difference box dimension method. This method estimates the fractal dimension by covering the grid of the image. As the grid size decreases, the number of grids required is calculated, and thus the fractal dimension is estimated.

[0151] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A metal-ceramic composite material, characterized in that, include: Metal matrix, ceramic particles with first fractal dimension and ceramic particles with second fractal dimension; The first fractal dimension is greater than the second fractal dimension.

2. The metal-ceramic composite material according to claim 1, characterized in that, The volume percentage of the metal matrix is ​​60%-95%, and the volume percentage of the ceramic particles of the first fractal dimension and the ceramic particles of the second fractal dimension is 5%-40%.

3. The metal-ceramic composite material according to claim 1, characterized in that, The metal matrix includes an aluminum matrix, a copper matrix, a titanium matrix, or a magnesium matrix.

4. The metal-ceramic composite material according to claim 1, characterized in that, The metal matrix includes an aluminum matrix, which comprises silicon, magnesium, and aluminum. In the aluminum matrix, the mass percentage of silicon is 0.01%-6%, and the mass percentage of magnesium is 0.02%-5%.

5. The metal-ceramic composite material according to any one of claims 1-4, characterized in that, The ceramic particles include at least one of silicon carbide particles, alumina particles, tungsten particles, and boron particles.

6. The metal-ceramic composite material according to any one of claims 1-4, characterized in that, The first fractal dimension is 2-3, and the second fractal dimension is 1-2.

7. The metal-ceramic composite material according to any one of claims 1-4, characterized in that, In the ceramic particles of the first fractal dimension and the ceramic particles of the second fractal dimension, the volume percentage of the ceramic particles of the first fractal dimension is 50%-90%, and the volume percentage of the ceramic particles of the second fractal dimension is 10%-50%.

8. The metal-ceramic composite material according to any one of claims 1-4, characterized in that, The particle size of the ceramic particles with the first fractal dimension and the ceramic particles with the second fractal dimension, and their volume percentages, satisfy the following relationship: Where ds represents the particle size of ceramic particles with the first fractal dimension and ceramic particles with the second fractal dimension, and Vs represents the volume percentage of ceramic particles with the first fractal dimension and ceramic particles with the second fractal dimension.

9. The metal-ceramic composite material according to claim 8, characterized in that, The particle size of the ceramic particles with the first fractal dimension and the ceramic particles with the second fractal dimension is 0.05μm-20μm.

10. A method for preparing a metal-ceramic composite material according to any one of claims 1-9, characterized in that, The method includes: The metal matrix, ceramic particles of the first fractal dimension and ceramic particles of the second fractal dimension are mixed and pressed into shape to obtain a green body. The green blank is subjected to hot forging, extrusion and rolling to obtain the metal-ceramic composite material.

11. The preparation method according to claim 10, characterized in that, The pressing pressure is 50MPa-200MPa, and the holding time is 1min-60min.

12. The preparation method according to claim 10, characterized in that, The sintering heating rate of the hot forging is 1℃ / min-15℃ / min, the sintering temperature is 400℃-650℃, the holding time is 1h-6h, the pressure is 50MPa-300MPa, and the holding time is 1min-60min.

13. The preparation method according to claim 10, characterized in that, The extrusion ratio is 5-30, and the heating temperature is 400℃-600℃.

14. The preparation method according to claim 10, characterized in that, The heating temperature for rolling is 400℃-600℃.

15. A vehicle, characterized in that, Including the metal-ceramic composite material according to any one of claims 1-9.

16. An electronic device, characterized in that, Including the metal-ceramic composite material according to any one of claims 1-9.

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