Preparation method and application of foamy copper reinforced aluminum-based composite material

Abstract

The invention provides a preparation method and application of a foamy copper reinforced aluminum-based composite material, and belongs to the technical field of aluminum-based composite material preparation. According to the foamy copper reinforced aluminum-based composite material, a variable-frequency and variable-power ultrasonic vibration assisted centrifugal casting technology is adopted, strong centrifugal force and the ultrasonic cavitation effect are utilized, so that the biological flowability of aluminum water is improved, the wettability between aluminum and copper is improved, and in combination with the effects of an auxiliary agent and Zn-Al or Sn-Al intermediate alloy, the foamy copper reinforced aluminum-based composite material is obtained. The problem that the binding force of foamy copper and an aluminum matrix is poor is solved, the adopted ultrasonic power is low (smaller than or equal to 1000 W), the preparation technology is simple, the obtained foamy copper reinforced aluminum matrix composite is free of obvious cracks and holes and high in density and thermal diffusion coefficient, and a light intelligent thermal management material can be provided for the field of electronic equipment.

Description

Technical Field

[0001] This invention relates to the field of aluminum-based composite material preparation technology, and more specifically, to a method for preparing copper foam reinforced aluminum-based composite material and its application. Background Technology

[0002] Aluminum alloys, with their lightweight, high strength, and excellent thermal and electrical conductivity, are widely used in engineering fields, particularly in electronic power conduction and heat exchange materials. While pure aluminum exhibits good thermal conductivity at room temperature, its low yield strength necessitates the use of a casting method in which highly thermally conductive alloying elements like Cu and Ag are added. However, the solid dissolution of Cu and Ag within the Al crystal lattice causes severe lattice distortion in the aluminum matrix, resulting in a decrease in both thermal and electrical conductivity. Furthermore, for aluminum-based composite materials, powder metallurgy using highly conductive and thermally conductive fillers such as copper powder, diamond, and graphene has not significantly improved thermal and electrical conductivity due to the discontinuous nature of the fillers within the aluminum matrix.

[0003] To address the above problems, this invention utilizes the high electrical and thermal conductivity of copper, using copper foam as the framework for aluminum. The three-dimensional, interconnected network structure of copper foam provides continuous and efficient electron movement paths within the aluminum, constructing a continuous metallization network, thereby improving the material's electrical and thermal conductivity. However, if conventional gravity casting is used for preparation, the poor flow properties of molten aluminum and the lack of wettability with copper make bonding between the aluminum and copper very difficult. This results in a composite material with numerous porosity defects, which is detrimental to improving the material's mechanical, electrical, and thermal conductivity properties. Therefore, controlling the effective connection and locking between the reinforcing phase, copper foam, and the aluminum matrix in the composite material is crucial for improving its electrical and thermal conductivity.

[0004] Patent CN104532031 A discloses a method for preparing aluminum-based composite materials reinforced with nano-ceramic particles. In this method, high-energy ultrasound is introduced into the aluminum alloy melt. The cavitation and acoustic flow generated by the ultrasound significantly promote the wetting and dispersion of the nano-ceramic particles, resulting in a fine-grained and uniformly distributed aluminum-based nanocomposite material. However, the power of the high-energy ultrasound is only 1-3 kW, leading to high energy consumption and increased production costs. Patent CN110358943 A discloses an in-situ synthesis method for preparing biphasic particle-reinforced aluminum-based composite materials. This method introduces ultrasound and stirring, achieving a dispersed distribution of biphasic particles under the combined effects of centrifugal force and ultrasound. The ultrasound intensity is 100-2000 W, the stirring speed is 100-1200 r / min, and the reaction time is 5-200 min. The resulting aluminum-based composite material exhibits simultaneous improvements in mechanical and thermal conductivity. However, the ultrasound applied in this method is primarily high-power, and its improvement on defects such as pores and cracks in the aluminum-based composite material is limited. Summary of the Invention

[0005] The technical problem to be solved by this invention is to overcome the difficulty of bonding between the foamed copper reinforcing phase and aluminum in existing aluminum-based composite materials, resulting in composite materials with many pore defects, which is not conducive to improving the thermal conductivity of the material. This invention provides a foamed copper reinforced aluminum-based composite material that solves the problem of physical fusion between foamed copper and aluminum alloy. The reaction process is simple and has low energy consumption. The prepared aluminum-based composite material has high density, no obvious cracks and pores, and good thermal conductivity.

[0006] The purpose of this invention is to provide a method for preparing copper foam reinforced aluminum matrix composite materials.

[0007] The above-mentioned objective of the present invention is achieved through the following technical solution: The preparation method of the foamed copper reinforced aluminum matrix composite material of the present invention includes the following steps: S1: Immerse the foamed copper in the flux suspension and dry it to obtain pretreated foamed copper; S2: The aluminum matrix and the intermediate alloy are fused together, and the slag is removed to obtain a liquid alloy; the aluminum matrix is ​​selected from at least one of pure aluminum or cast aluminum alloy; the intermediate alloy is selected from one or both of Zn-Al alloy or Sn-Al alloy, and the intermediate alloy accounts for 2-10% of the total weight of the aluminum matrix, the intermediate alloy and the foamed copper; S3: Preheat the pretreated foamed copper to a temperature above the melting point of the alloy liquid; S4: Rotate the preheated foamed copper at a speed of 800~6000rpm, inject the alloy liquid, rotate for 2~5 minutes, so that the alloy liquid is thrown into the pores of the foamed copper by centrifugal force. S5: Apply ultrasound to the product obtained after step S4 to make hydrogen bubbles in the aluminum melt grow and escape. The frequency of the ultrasound is 20~22kHz and the power of the ultrasound is 200~500W. S6: Cooling. When the temperature drops to the solid-liquid coexistence temperature of the alloy liquid, adjust the frequency of the ultrasound to 18~20kHz and the power of the ultrasound to 500~1000W until it is fully formed. Then stop rotating to obtain the foamed copper reinforced aluminum matrix composite material.

[0008] Specifically, the cleaning steps before soaking the foamed copper are as follows: ultrasonic cleaning of the foamed copper with dilute acid to remove copper oxide, oil stains and other surface impurities, followed by rinsing the foamed copper with water to remove the dilute acid from the surface.

[0009] More specifically, the dilute acid is one or a mixture of hydrochloric acid, sulfuric acid, nitric acid solution or acetic acid solution; More specifically, when the dilute acid is a mixed solution of hydrochloric acid, sulfuric acid, and nitric acid, the volume concentration of nitric acid is 20% to 30%, the volume concentration of sulfuric acid is 50% to 60%, and the volume concentration of hydrochloric acid is 0.3% to 0.8%.

[0010] Preferably, the dilute acid is an acetic acid solution.

[0011] More specifically, the volume concentration of the acetic acid solution is 1-5%, specifically 1%, 2%, 3%, 4%, 5%, and more preferably, the volume concentration of the acetic acid solution is 1% and 5%.

[0012] More specifically, the ultrasonic cleaning time is 10-30 minutes, specifically 10 minutes, 15 minutes, 20 minutes, 25 minutes, or 30 minutes, preferably 10 minutes.

[0013] Specifically, the copper foam has a pore size of 0.1~10mm, a porosity of 95~98%, and a bulk density of 0.1~0.8g / cm³. 3 .

[0014] Specifically, the pore size of the foamed copper can be 0.1mm, 0.5mm, 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, or 10mm. More preferably, the pore size of the foamed copper is 0.1mm, 2mm, or 10mm.

[0015] Preferably, the bulk density of the copper foam is 0.35~0.6 g / cm³. 3 Specifically, the bulk density of the copper foam is 0.35 g / cm³. 3 0.4g / cm 3 and 0.6 g / cm 3 .

[0016] Specifically, the flux suspension contains additives selected from potassium fluoroaluminate or cesium fluoroaluminate, or a mixture thereof; the additives improve the wettability between copper and aluminum, thereby improving the interfacial bonding force between copper and aluminum.

[0017] More specifically, when the additive is a mixture of potassium fluoroaluminate and cesium fluoroaluminate, the mass ratio of potassium fluoroaluminate to cesium fluoroaluminate is 0.25 to 2:1, specifically 1:4, 1:3, 1:2, 1:1, 2:1, preferably 1:3.

[0018] Specifically, the weight ratio of the flux to water in the flux suspension is 5~15:100; Preferably, the weight ratio of flux to water in the flux suspension is 5~8:100; specifically, it can be 5:100, 6:100, 7:100, or 8:100; more preferably, the weight ratio of flux to water in the flux suspension is 5:100 or 8:100.

[0019] Specifically, the soaking time is 5 to 30 minutes.

[0020] Preferably, the soaking time is 5 to 15 minutes; specifically, it can be 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes, 12 minutes, or 15 minutes. More preferably, the soaking time is 5 minutes, 6 minutes, 10 minutes, or 15 minutes.

[0021] Specifically, the pure aluminum is selected from at least one of the following industrial pure aluminum series: 1080, 1080A, 1070, 1070A, 1370, 1060, 1050, and 1050A, with industrial pure aluminum 1060 being preferred.

[0022] Specifically, the cast aluminum alloy is selected from at least one of aluminum-silicon alloy, aluminum-magnesium alloy, or aluminum-zinc alloy; preferably, the aluminum-silicon alloy is Al-6Si alloy, the aluminum-magnesium alloy is 4047 alloy, and the aluminum-zinc alloy is 6201 alloy.

[0023] Specifically, the intermediate alloy is selected from one or both of Zn-Al alloys and Sn-Al alloys.

[0024] More specifically, the Zn-Al alloy or Sn-Al alloy contains 2-20% aluminum by weight percentage; the mechanism of adding the intermediate alloy is that the Zn-Al alloy and Sn-Al alloy can form good metallurgical bonding layers with copper and aluminum respectively, so as to achieve good welding between aluminum and copper.

[0025] Preferably, the Zn-Al alloy is a Zn-Al8 alloy, and the Sn-Al alloy is a Sn-Al5 alloy, a Sn-Al8 alloy, or a Sn-Al20 alloy.

[0026] More specifically, the intermediate alloy accounts for 2 to 10% of the total weight of the composite material.

[0027] Preferably, the intermediate alloy accounts for 2-5% of the total weight of the composite material, specifically 2%, 3%, 4%, or 5%; more preferably, the intermediate alloy accounts for 2% and 3% of the total weight of the composite material.

[0028] Specifically, the preparation steps of the alloy liquid in step S2 are as follows: heating pure aluminum or cast aluminum alloy to melt, adding intermediate alloy, holding at the temperature, and removing slag to obtain alloy liquid.

[0029] More specifically, the heating temperature is 650~750℃; specifically, the heating temperature is 650℃, 700℃ and 750℃.

[0030] More specifically, the heat preservation time is 30-60 minutes; specifically, it can be 30 minutes, 40 minutes, 50 minutes, or 60 minutes, and more preferably 30 minutes.

[0031] Specifically, the preheating temperature in step S3 is 650~850℃.

[0032] Preferably, the preheating temperature in step S3 is 650~750℃; specifically, the preheating temperature is 650℃, 660℃, 700℃ and 750℃.

[0033] Specifically, the rotation speed in step S4 is 800~6000 rpm; specifically, it can be 800 rpm, 900 rpm, 1000 rpm, 1200 rpm, 1500 rpm, 2000 rpm, 2500 rpm, 3000 rpm, 4000 rpm, or 5000 rpm. More preferably, the rotation speed in step S4 is 800 rpm, 1200 rpm, 4000 rpm, or 6000 rpm.

[0034] Specifically, the rotation time in step S4 is 2 to 5 minutes; specifically, the rotation time in step S4 is 2 minutes, 3 minutes, 4 minutes, and 5 minutes.

[0035] Specifically, the frequency of the ultrasound in step S5 is 20~22kHz; specifically, it can be 20kHz, 21kHz, or 22kHz, and more preferably 20kHz and 22kHz.

[0036] Specifically, the power of the ultrasound in step S5 is 200~500W; specifically, the power of the ultrasound is 200W, 300W, 400W and 500W.

[0037] Specifically, the frequency of the ultrasound in step S6 is 18~20kHz; specifically, it can be 18kHz, 19kHz, or 20kHz, and more preferably 18kHz and 20kHz.

[0038] Specifically, the power of the ultrasound in step S6 is 500~1000W; specifically, it can be 500W, 600W, 700W, 800W, 900W, or 1000W. More preferably, the power of the ultrasound in step S6 is 500W, 600W, 700W, or 1000W.

[0039] Specifically, the ultrasound time in step S5 is 60~240s; specifically, it can be 60s, 80s, 100s, 120s, 150s, 180s, 200s, or 240s. More preferably, the ultrasound time in step S5 is 60s, 150s, 180s, or 240s.

[0040] The ultrasound duration in step S6 is 60~240s; specifically, it can be 60s, 80s, 100s, 120s, 150s, 180s, 200s, or 240s. More preferably, the ultrasound duration in step S6 is 60s, 150s, or 240s.

[0041] This invention also protects a foamed copper-reinforced aluminum-based composite material, which is prepared by the above-described preparation method.

[0042] This invention also protects the application of the foamed copper-reinforced aluminum matrix composite material prepared by the above preparation method in the preparation of lightweight intelligent thermal management materials.

[0043] This invention uses foamed copper as the "skeleton" and aluminum as the "muscle." The design principle of this composite structure is as follows: The unique characteristics of copper foam are mainly reflected in its high surface area, high electrical conductivity, and high thermal conductivity. The tortuous flow path enhances heat dispersion. Cu is an excellent electronic conductor, with electrons traveling at near the speed of light within it. Furthermore, copper foam possesses a very high surface area, and its tortuous nature provides a complex, meandering three-dimensional network of electron flow paths, thereby enhancing heat dispersion. According to Joule's law: (1) (2) In equation (1), Q is Joule heat, I is current (A), R is resistance (Ω), and t is time (s); in equation (2), P is electric power (W), U is voltage (V), and I is current (A).

[0044] From formula (1), it can be seen that Q and I 2 Proportional to R, the copper skeleton in the material prepared by this invention is the main electronic conductor. Most electrons will spontaneously choose the link with less obstruction (the direction with less resistance) for near-light speed transmission, thereby generating a very high Joule heat Q.

[0045] The pure aluminum or cast aluminum alloys mentioned above are lightweight and have good corrosion resistance. After electrical energy is converted into heat energy, the heat is transferred from the copper mesh along the direction of the lower-temperature aluminum matrix. This heat transfer inside the metal is also achieved by the conduction of free electrons within the metal. These free electrons are transferred to the aluminum matrix in a uniform scattering manner, so that the heat can be output outward in a uniform distribution. The relationship between heat and temperature is as shown in equation (3): (3) In Equation 3, c represents the specific heat capacity, m represents the mass, and the temperature change represents the temperature. Pure aluminum has a specific heat capacity of 0.9 J / g·℃, which is relatively high among many non-ferrous metals. This means that a unit mass of aluminum requires less heat to raise its temperature, exhibiting excellent energy storage properties. It also has good electrical and thermal conductivity.

[0046] In summary, the copper skeleton in the composite material prepared by this invention is used to increase Joule heating, and the aluminum matrix is ​​used to utilize heat efficiently. The assembly of the two materials in this structure is beneficial to improving the thermal diffusivity and electrothermal conversion capability, providing a high-strength intelligent thermal management material for the field of electronic devices.

[0047] Furthermore, aluminum alloy melt has high viscosity and poor fluidity. Using conventional casting techniques, gravity alone is insufficient to allow the molten aluminum to penetrate the small pores of the foamed copper. This invention employs centrifugal casting, utilizing the centrifugal force formula G = 1.11 × 10⁻⁶. -5 ×R×(rpm) 2 R is the radius of rotation, and rpm is the rotational speed. The formula shows a large centrifugal force, sufficient to completely penetrate the aluminum molten molecules into the pores of the foamed copper, creating the basic conditions for bonding between copper and aluminum. The poor wettability between copper and aluminum is mainly due to the oxide layer on the copper surface and the large difference in melting points between aluminum and copper, resulting in a high temperature for the interfacial reaction and poor bonding between the copper skeleton and the aluminum matrix. Therefore, this invention uses an additive pre-attached inside the foamed copper. During mold preheating, the additive melts first and removes the oxide film on the copper surface, eliminating the intermediate barrier for bonding between aluminum and copper. After melting, aluminum easily absorbs moisture from the air, generating H2, which easily leads to porosity defects inside the composite material. Ultrasonic vibration is added before the aluminum melt begins to solidify, utilizing the ultrasonic cavitation effect to achieve venting. The gas is discharged through the gap between the upper and lower molds. When the ultrasonic temperature is above the melting point of the aluminum matrix, the aluminum matrix is ​​in a fully liquid state. The applied ultrasound is mainly high-frequency and low-power, with a frequency range of 20~22kHz and a power range of 200~500W. At this time, the ultrasonic energy is mainly used to promote the growth and escape of hydrogen bubbles in the aluminum melt. However, in cases where aluminum alloys are prone to forming dendritic coarse grains, which reduces the strength of the composite material, the ultrasonic temperature is within the solid-liquid coexistence temperature range. When crystal nuclei or pre-precipitated crystals appear in the aluminum melt, in order to eliminate the excessive growth of the pre-precipitated phase, the applied ultrasound is low-frequency and high-power, with an ultrasonic frequency range of 18~20kHz and a power range of 500~1000W. At this time, the ultrasonic energy can promote cavitation reaction and cause cavitation bubbles to collapse rapidly. The strong pressure generated when the cavitation bubbles collapse can effectively break the grains of the pre-precipitated phase, so that the overall aluminum matrix has a uniform and fine grain state, thereby ensuring the strength of the composite material.

[0048] Compared with the prior art, the beneficial effects of the present invention are: The present invention relates to a method for preparing aluminum-based composite materials, which utilizes centrifugal casting technology assisted by ultrasonic vibration applied in a variable frequency and power manner. Combined with the effects of cesium fluoroaluminate additives and intermediate alloys Zn-Al or Sn-Al alloys, this method overcomes the problems of poor fluidity of molten aluminum and physical fusion and wetting between copper foam and aluminum alloy during conventional casting. The preparation process is simple, with low reaction energy consumption (ultrasonic power ≤1000W), and the prepared foamed copper-aluminum-based composite material exhibits good aluminum-copper bonding strength and is free from obvious defects such as pores and cracks. Furthermore, the prepared foamed copper-aluminum-based composite material has a high density (2.70~2.76 g / cm³). 3 It has good thermal conductivity (100.48~110.52mm). 2 s -1 ) and tensile strength (112.26~165.49Mpa). Attached Figure Description

[0049] Figure 1 A schematic diagram of the apparatus for preparing copper-reinforced aluminum-based composite materials by ultrasonic-assisted centrifugal casting.

[0050] 1-Upper mold; 2-Lower mold; 11-Gate; 12-Runner; 3-Fastener; 4-Induction heating coil; 5-Rotating table; 6-Foamed copper reinforced aluminum matrix composite material; 61-Foamed copper; 62-Molten aluminum; 7-Ultrasonic generator.

[0051] Figure 2 The morphology of the foamed copper in Example 1 is shown.

[0052] Figure 3 Schematic diagrams of the electrical and thermal conductivity mechanisms of the materials: (a) Electron flow path in copper foam; (b) Electron flow path in copper foam reinforced aluminum composite material.

[0053] Figure 4 The internal microstructure of the aluminum-based composite materials prepared in Examples 1-4 are shown in the following figures: (a) Example 1, (b) Example 2, (c) Example 3, and (d) Example 4.

[0054] Figure 5 The internal microstructures of the aluminum-based composite materials prepared for comparative examples 1-4 are as follows: (a) Comparative example 1, (b) Comparative example 2, (c) Comparative example 3, (d) Comparative example 4, (e) Comparative example 9.

[0055] Figure 6 Microstructures of the aluminum substrates prepared in Examples 1-4: (a) Example 1, (b) Example 2, (c) Example 3, (d) Example 4.

[0056] Figure 7Microstructures of aluminum-based raw materials for comparative examples 5-8: (a) Comparative example 5, (b) Comparative example 6, (c) Comparative example 7, (d) Comparative example 8, (e) Comparative example 9. Detailed Implementation

[0057] The present invention will be further described below with reference to specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise stated, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents.

[0058] The ultrasonic-assisted centrifugal casting device used in this invention is as follows: Figure 1 As shown, the mold is divided into an upper mold 1 and a lower mold 2. The upper mold 1 includes a gate 11 and a runner 12, providing a casting channel for molten aluminum. The gate is flared to ensure sufficient flow and that the solidified aluminum can be easily demolded after mold opening. The materials of the upper mold 1 and the lower mold 2 can be stainless steel or titanium alloy to ensure good corrosion resistance. The parting line design between the upper and lower molds facilitates the easy removal of the foamed copper reinforced aluminum matrix composite material 6 during mold opening and provides an venting channel for the molten aluminum. 3 is a fastener, which is used to press the upper mold 1 and the lower mold together. 2 and 4 are induction heating coils, installed inside fastener 3, which automatically preheat the upper mold 1 and lower mold 2; 5 is a rotating table, which makes the molten aluminum subject to extremely high centrifugal force when the rotating table rotates at high speed, so that the molten aluminum can penetrate into the pores of the foamed copper. The rotation speed of the rotating table is 800~6000rpm; 6 is a foamed copper reinforced aluminum matrix composite material, which is obtained by cooling foamed copper 61 and molten aluminum; 7 is an ultrasonic generator, which provides ultrasonic vibration to promote the degassing of molten aluminum and the refinement of the pre-precipitated phase during the solidification of aluminum alloy. Figure 1 (a) Placement of foamed copper 61; (b) After mold closing, pour molten aluminum 62 into the mold cavity, start the rotary table 5, and turn on the ultrasonic generator 7; (c) After cooling and forming, open the mold and remove the foamed copper reinforced aluminum matrix composite material 6.

[0059] Example 1 A foamed copper-reinforced aluminum-based composite material is prepared by the following method: Raw material preparation: Industrial pure aluminum 1060; foamed copper, with a pore size of 10mm, a porosity of 95-98%, and a bulk density of 0.4g / cm³. 3 Zn-Al8 master alloy; Cesium fluoroaluminate additive.

[0060] Step 1: Ultrasonic cleaning of the foamed copper for 10 minutes using a 1% acetic acid solution to remove copper oxide, oil, and other surface impurities; then rinsing the foamed copper with deionized water and immersing it in a flux suspension for 5 minutes, followed by drying; the ratio of the cesium fluoroaluminate to water is 5:100 by mass percentage. Step 2: Heat industrial pure aluminum 1060 to 750℃ to melt it to obtain aluminum liquid. Then add Zn-Al8 master alloy accounting for 2% of the total weight of aluminum matrix, master alloy and foamed copper to the aluminum liquid, hold for 30 minutes, and remove slag. Step 3: Place the copper foam in Figure 1 The mold cavity shown is preheated using induction heating coil 4 to a temperature of 660℃; the mold is as follows... Figure 1 As shown, the mold is divided into upper mold 1 and lower mold 2, and the materials of upper mold 1 and lower mold 2 are stainless steel.

[0061] Step 4: Turn on the rotary table 5 switch, set the rotation speed to 800 rpm, and pour the molten aluminum from Step 2 into it. Figure 1 The gate 11 shown is rotated for 2 minutes, causing the molten aluminum to be thrown into the pores of the foamed copper by strong centrifugal force.

[0062] Step 5: Turn on the ultrasonic generator 7. The ultrasonic transducer converts electrical energy into mechanical energy and applies ultrasonic vibration to the bottom of the lower mold. The ultrasonic frequency is 20kHz, the ultrasonic power is 200W, and the ultrasonic vibration time is 60s. At this time, the ultrasonic energy is mainly used to promote the growth and escape of hydrogen bubbles in the aluminum melt. Step 6: Turn off the induction heating coil 4 to cool down. When the temperature drops to about 550℃, adjust the ultrasonic frequency and power to 20kHz and 500W respectively. Apply ultrasonic vibration for 60s until it is fully formed. Then stop the rotation of the rotary table 5, open the mold and take out the sample.

[0063] Example 2 A foamed copper-reinforced aluminum-based composite material is prepared by the following method: Raw material preparation: Al-6Si alloy; copper foam with a pore size of 2 mm, a porosity of 95-98%, and a bulk density of 0.6 g / cm³. 3 Sn-Al5 master alloy; cesium fluoroaluminate additive.

[0064] Step 1: Ultrasonic cleaning of the foamed copper for 10 minutes using a 5% acetic acid solution to remove copper oxide, oil, and other surface impurities; then rinsing the foamed copper with deionized water and immersing it in a flux suspension for 10 minutes, followed by drying; the ratio of the cesium fluoroaluminate to water is 8:100 by mass percentage. Step 2: Heat the Al-6Si alloy to 650℃ to melt it and obtain an alloy liquid. Then add Sn-Al5 master alloy accounting for 2% of the total weight of aluminum matrix, master alloy and foamed copper to the alloy liquid, hold for 30 minutes, and remove the slag. Step 3: Place the copper foam in Figure 1The mold cavity shown is preheated using induction heating coil 4 at a temperature of 650℃; the mold is as follows... Figure 1 As shown, the mold is divided into upper mold 1 and lower mold 2, and the materials of upper mold 1 and lower mold 2 are stainless steel.

[0065] Step 4: Turn on the rotary table 5 switch, set the rotation speed to 1200 rpm, and pour the alloy liquid from Step 2 into it. Figure 1 The gate 11 shown is rotated for 5 minutes, which allows the molten aluminum to be thrown into the pores of the foamed copper by strong centrifugal force.

[0066] Step 5: Turn on the ultrasonic generator 7. The ultrasonic transducer converts electrical energy into mechanical energy and applies ultrasonic vibration to the bottom of the lower mold. The ultrasonic frequency is 20kHz, the ultrasonic power is 400W, and the ultrasonic vibration time is 240s. At this time, the ultrasonic energy is mainly used to promote the growth and escape of hydrogen bubbles in the aluminum melt. Step 6: Turn off the induction heating coil 4 to cool down. When the temperature drops to about 580℃, adjust the ultrasonic frequency and power to 20kHz and 700W respectively. Apply ultrasonic vibration for 240s until it is fully formed. Then stop the rotation of the rotary table 5, open the mold and take out the sample.

[0067] Example 3 A foamed copper-reinforced aluminum-based composite material is prepared by the following method: Raw material preparation: 4047 alloy; copper foam with a pore size of 2mm, a porosity of 95-98%, and a bulk density of 0.6g / cm³. 3 Sn-Al8 master alloy; additives are a mixture of cesium fluoroaluminate and potassium fluoroaluminate (mass ratio 1:3).

[0068] Step 1: Ultrasonic cleaning of the foamed copper for 10 minutes using a 5% acetic acid solution to remove copper oxide, oil, and other surface impurities; then rinsing the foamed copper with deionized water and immersing it in a flux suspension for 6 minutes, followed by drying; the ratio of the cesium fluoroaluminate and potassium fluoroaluminate mixture (mass ratio of 1:3) to water is 10:100 by mass percentage. Step 2: Heat the Al-6Si alloy to 700℃ to melt it and obtain an alloy liquid. Then add Sn-Al8 master alloy accounting for 2% of the total weight of aluminum matrix, master alloy and foamed copper to the alloy liquid, hold for 30 minutes, and remove the slag. Step 3: Place the copper foam in Figure 1 The mold cavity shown is preheated using induction heating coil 4 at a temperature of 700℃; the mold is as follows... Figure 1 As shown, the mold is divided into upper mold 1 and lower mold 2, and the materials of upper mold 1 and lower mold 2 are stainless steel.

[0069] Step 4: Turn on the rotary table 5 switch, set the rotation speed to 4000 rpm, and pour the alloy liquid from Step 2 into it. Figure 1 The gate 11 shown is rotated for 4 minutes, which causes the molten aluminum to be thrown into the pores of the foamed copper by strong centrifugal force.

[0070] Step 5: Turn on the ultrasonic generator 7. The ultrasonic transducer converts electrical energy into mechanical energy and applies ultrasonic vibration to the bottom of the lower mold. The ultrasonic frequency is 22kHz, the ultrasonic power is 300W, and the ultrasonic vibration time is 150s. At this time, the ultrasonic energy is mainly used to promote the growth and escape of hydrogen bubbles in the aluminum melt. Step 6: Turn off the induction heating coil 4 to cool down. When the temperature drops to about 580℃, adjust the ultrasonic frequency and power to 18kHz and 600W respectively. Apply ultrasonic vibration for 150s until it is fully formed. Then stop the rotation of the rotary table 5, open the mold and take out the sample.

[0071] Example 4 A foamed copper-reinforced aluminum-based composite material is prepared by the following method: Raw material preparation: 6201 alloy; copper foam with a pore size of 0.1 mm, a porosity of 95-98%, and a bulk density of 0.35 g / cm³. 3 Sn-Al20 master alloy; potassium fluoroaluminate additive.

[0072] Step 1: Ultrasonic cleaning of the foamed copper for 10 minutes using a 5% acetic acid solution to remove copper oxide, oil, and other surface impurities; then rinsing the foamed copper with deionized water and immersing it in a flux suspension for 15 minutes, followed by drying; the ratio of the additive potassium fluoroaluminate to water is 8:100 by mass percentage. Step 2: Heat the 6201 alloy to 750℃ to melt it and obtain an alloy liquid. Then add Sn-Al5 master alloy accounting for 3% of the total weight of aluminum matrix, master alloy and foamed copper to the alloy liquid, hold for 30 minutes, and remove the slag. Step 3: Place the copper foam in Figure 1 The mold cavity shown is preheated using induction heating coil 4 to a temperature of 750℃; the mold is as follows... Figure 1 As shown, the mold is divided into upper mold 1 and lower mold 2, and the materials of upper mold 1 and lower mold 2 are stainless steel.

[0073] Step 4: Turn on the rotary table 5 switch, set the rotation speed to 6000 rpm, and pour the alloy liquid from Step 2 into it. Figure 1 The gate 11 shown is rotated for 3 minutes, causing the molten aluminum to be thrown into the pores of the foamed copper by strong centrifugal force.

[0074] Step 5: Turn on the ultrasonic generator 7. The ultrasonic transducer converts electrical energy into mechanical energy and applies ultrasonic vibration to the bottom of the lower mold. The ultrasonic frequency is 22kHz, the ultrasonic power is 500W, and the ultrasonic vibration time is 180s. At this time, the ultrasonic energy is mainly used to promote the growth and escape of hydrogen bubbles in the aluminum melt. Step 6: Turn off the induction heating coil 4 to cool down. When the temperature drops to about 580℃, adjust the ultrasonic frequency and power to 18kHz and 1000W respectively. Apply ultrasonic vibration for 240s until it is fully formed. Then stop the rotation of the rotary table 5, open the mold and take out the sample.

[0075] Comparative Example 1 Compared with Example 1, the preparation of steps 1 to 3 is the same as in Example 1, except that: Step 4: the molten aluminum from step 2 is poured into Figure 1 The gate 11 shown is used to fill the mold with molten aluminum. The rotary table 5 and the ultrasonic generator 7 are not turned on. Step 5: After the induction heating coil 4 is turned off and the mold is cooled and formed, the mold is opened and the sample is taken out.

[0076] Comparative Example 2 Compared with Example 2, the preparation of steps 1 to 3 is the same as in Example 2, except that: Step 4: the molten aluminum from step 2 is poured into Figure 1 The gate 11 shown is used to fill the mold with molten aluminum. The rotary table 5 and the ultrasonic generator 7 are not turned on. Step 5: After the induction heating coil 4 is turned off and the mold is cooled and formed, the mold is opened and the sample is taken out.

[0077] Comparative Example 3 Compared with Example 3, the only difference is that the additive cesium fluoroaluminate is not added; the other steps are the same as in Example 3.

[0078] Comparative Example 4 Compared with Example 4, the only difference is that Sn-Al2O intermediate alloy is not added; the other steps are the same as in Example 4.

[0079] Comparative Example 5 The raw material, industrial pure aluminum 1060 plate, is in a cast state. The 1060 aluminum granules are heated to 750℃ to melt, held at that temperature for 30 minutes, slag is removed, and the mixture is poured into a mold and cooled. It is then wire-cut into plates, and samples are taken out for testing.

[0080] Comparative Example 6 The raw material Al-6Si is a cast alloy. The Al-6Si alloy is heated to 650℃ to melt, held for 30 minutes, slag is removed, and the mixture is poured into a mold and cooled. It is then wire-cut into plates, and the samples are taken out for testing.

[0081] Comparative Example 7 The raw material, 4047 aluminum alloy, is in a cast state. The 4047 aluminum alloy is heated to 700℃ to melt, held at that temperature for 30 minutes, slag is removed, and the alloy is poured into a mold and cooled. It is then wire-cut into plates, and samples are taken out for testing.

[0082] Comparative Example 8 The raw material, 6201 aluminum alloy, is in a cast state. The 6201 aluminum alloy is heated to 750℃ to melt, held at that temperature for 30 minutes, slag is removed, and the alloy is poured into a mold and cooled. It is then wire-cut into plates, and samples are taken out for testing.

[0083] Comparative Example 9 Compared with Example 3, the only difference is that the ultrasonic frequency in step 5 is adjusted to 18kHz and the ultrasonic power is adjusted to 600W; the ultrasonic frequency in step 6 is adjusted to 22kHz and the ultrasonic power is adjusted to 300W, and the other steps are the same as in Example 3.

[0084] Result detection Microstructure observation and analysis: Microstructure observation was performed using a Leica Microsystems DMi8C intelligent digital inverted metallographic microscope (OM). To quantitatively analyze the grain size of the metallographic structure, 10 metallographic images were randomly selected from each sample. ImageJ software was used to calculate the pixel count, measure the length and width of α-Al secondary dendrites, the length of primary silicon, and the length of eutectic silicon, and calculate their average values.

[0085] Tensile strength: The strength of the prepared material was tested using a universal testing machine from Shanghai Hualong according to the national standard GB / T 228.1-2010, with a tensile rate of 0.6 mm / min.

[0086] Thermal conductivity: The thermal diffusivity of the material was measured using a LFA-467 flash laser thermal conductivity meter according to GB / T 3651-2008.

[0087] Figure 2 The morphology of the copper foam used in Example 1 is shown below. It should be noted that the copper foam used in other examples differs only in pore size; its morphology is similar to that used in Example 1. Figure 2 Similarly, by Figure 2 It can be seen that the pores inside the foamed copper are all interconnected, ensuring that the connection between the molten aluminum and the foamed copper is continuous.

[0088] Figure 3 (a) shows the electron flow path in copper foam. The unique characteristics of copper foam are mainly reflected in its high surface area, and the tortuous flow path enhances heat dispersion. As a high-quality electron conductor, Cu allows electrons to travel at speeds close to the speed of light in copper. Therefore, the electron flow in copper foam provides a complex and meandering three-dimensional network path. Figure 3(b) shows the electron flow path in the copper-reinforced aluminum foam composite material. The pure aluminum and cast aluminum alloys are lightweight and have good corrosion resistance. After electrical energy is converted into heat energy, the heat is transferred from the copper mesh along the direction of the lower-temperature aluminum matrix. This heat transfer inside the metal is also achieved by free electron conduction. These free electrons are transferred to the aluminum matrix in a uniform scattering manner, so that the heat can be output outward in a uniform distribution. The relationship between heat and temperature is as shown in equation (3): (3) In Equation 3 c For specific heat capacity, m The value is mass, expressed in g, and ΔT is the temperature change. Pure aluminum has a specific heat capacity of 0.9 J / g·℃, which is relatively high among many non-ferrous metals. This means that a unit mass of aluminum requires less heat to raise its temperature, giving it a good energy storage function. It also has good electrical and thermal conductivity.

[0089] Figure 3 This demonstrates that the copper skeleton in the composite material prepared by this invention is used to increase Joule heating, and the aluminum matrix is ​​used to utilize heat efficiently. The assembly of the two materials using this structure is beneficial to improving thermal conductivity and electrothermal conversion capability, providing a smart thermal management material for the field of electronic devices.

[0090] Figure 4 The microstructure of the composite materials prepared in Examples 1-4 is shown below. Figure 4 As can be seen, in Examples 1 to 4 of the present invention, the bonding between aluminum and copper is dense, and no obvious cracks or voids appear.

[0091] Comparative Example 1 used a conventional casting method to prepare copper-reinforced pure aluminum foam. Compared with Example 1, the rotary table and ultrasonic vibrator were not turned on. The internal microstructure of the prepared composite material is as follows: Figure 5 As shown in (a), from Figure 5 (a) It can be seen that the interior of the foamed copper is hollow, and the bond between the foamed copper and aluminum also has large pores. This is because ultrasonic-assisted centrifugal casting was not used, which resulted in the molten aluminum failing to penetrate and wet the foamed copper.

[0092] Comparative Example 2 of this invention uses a conventional casting method to prepare copper-reinforced Al-6Si foam. Compared with Example 2, the rotary table and ultrasonic vibrator are not turned on. The internal microstructure of the prepared composite material is as follows: Figure 5 As shown in (b). Figure 5 (b) It can be seen that although Al-6Si has better flow properties than pure aluminum 1060, the copper foam and aluminum still failed to bond together due to the absence of centrifugal force and ultrasonic vibration, resulting in large pores between them.

[0093] Compared to Example 3, Comparative Example 3 did not include the additive cesium fluoroaluminate, but all other steps were the same as in Example 3. The role of the additive cesium fluoroaluminate is to remove the oxide scale on the copper surface, thereby improving the wettability between copper and aluminum and enhancing interfacial adhesion. Figure 5 (c) It can be seen that there are many black oxide scales on the copper surface. As an intermediate barrier between aluminum and copper, the oxide scale will inevitably affect the bonding between the copper skeleton and the aluminum muscle. This is because no additives were added.

[0094] Comparative Example 4, compared to Example 4, did not include the Sn-Al2O master alloy; all other steps were the same as in Example 4. The Sn-Al2O master alloy was primarily used to improve the wettability of aluminum and copper foam, as Sn and copper bond more easily. Figure 5 (d) It can be seen that, due to the absence of a Sn-Al2O master alloy, a large gap remains in the bond between aluminum and copper. Furthermore, the lack of Sn-Al2O bonding between aluminum and copper results in a significant difference in their coefficients of thermal expansion, leading to crack defects in the composite material. Figure 5 (e) It can be seen that Comparative Example 9 is different only in the frequency and power of the ultrasound. All other steps are the same as in Example 3. The interface between copper and aluminum is clear and well bonded.

[0095] Figure 6 (a) shows the microstructure of the 1060 aluminum substrate prepared in Example 1. Figure 6 (b) shows the microstructure of the Al-6Si matrix in Example 2. Figure 6 (c) shows the microstructure of the 4047 aluminum matrix in Example 3. Figure 6 (d) shows the microstructure of the 6201 aluminum matrix in Example 4. Comparative Examples 5, 6, 7, and 8 are shown in the figure. Figure 7 (a) shows the microstructure of the 1060 aluminum-based raw material. Figure 7 (b) shows the microstructure of the Al-6Si aluminum-based raw material in Comparative Example 6. Figure 7 (c) shows the microstructure of the 4047 aluminum-based raw material in Comparative Example 7. Figure 7 (d) shows the microstructure of the 6201 aluminum-based raw material in Comparative Example 8. Figure 6 (a) The average grain size of the 1060 aluminum in Example 1 was calculated to be 45 μm. Figure 7 (a) In Comparative Example 5, the raw aluminum grain size is 82 μm, and the porosity defects are distributed along the grain boundaries, with a large number of pores. Figure 6 (b) The α-Al grain size of Example 2 shown is 29 μm, and the Si phase is in the form of fine fibers. Figure 7 (b) The α-Al grain size in Comparative Example 6 is 75 μm, the Si phase is needle-shaped, and there are pores of different sizes in the figure. Figure 6(c) The eutectic silicon in the 4047 aluminum alloy of Example 3 shown in Example 3 is in the form of long, thin fibers with a small number of very small pores, while Figure 7 The silicon phase in (c) is in the form of coarse strips, and large pores are visible in the figure. Figure 6 (d) and Figure 7 (d) Compared to, Figure 7 (d) Comparative Example 8 shows that the 6021 aluminum-based raw material has more porosity defects. The reason for the above difference is that ultrasonic waves were applied in all examples. Ultrasonic cavitation breaks up the α-Al crystals and refines the Si phase. The aluminum liquid achieves a good degassing effect under ultrasonic action, resulting in fewer porosity defects in Examples 1 to 4. Figure 7 (e) shows the microstructure of the aluminum matrix in Comparative Example 9. Unlike Example 3, in terms of the selection of ultrasonic oscillation parameters, low frequency and high power (18kHz, 600W) were used for oscillation in the fully liquid state of aluminum, while high frequency and low power (22kHz and 300W) were used at the liquid-solid coexistence temperature of aluminum. As a result, the grain refinement effect and hydrogen removal and degassing effect of aluminum were not as good as those in Example 3.

[0096] Table 1. Composite material properties of Examples 1-4

[0097] Table 2 Material properties of Comparative Examples 1-9

[0098] Table 1 shows the performance results of the composite materials in Examples 1-4. As can be seen from Table 1, the densities of the composite materials prepared in Examples 1-4 are all greater than 2.70 g / cm³. -3 This indicates a tight bond between the aluminum and the copper foam, while the densities of Comparative Examples 1-4 are all lower than those of Examples 1-4. The thermal diffusivity of the prepared composite materials is consistently higher than 100 mm². 2 s -1 The main reason is the tight bond between the foamed copper and aluminum, achieving a seamless connection between the two materials. Figure 4 This has been confirmed in practice. The copper foam acts as a framework, thus increasing Joule heating, while the aluminum "muscle" improves heat efficiency and significantly enhances the thermal diffusivity. Furthermore, the use of variable frequency and power ultrasonic vibration during the preparation process results in a low gas content in the composite material and a fine microstructure of the aluminum and aluminum alloys, which can... Figure 6 This has been confirmed in studies, resulting in its high tensile strength.

[0099] Table 2 shows the material properties of Comparative Examples 1-9. Comparative Example 1 used a conventional casting method to prepare copper-reinforced pure aluminum foam, and the resulting composite material had a density of only 2.12 g / cm³. -3The material density decreased by 23.18% compared to Example 1. This was because Comparative Example 1 did not use a rotating stage or apply ultrasonic vibration, preventing molten aluminum from penetrating the foamed copper. This resulted in numerous pores between the copper and aluminum, poor venting of the aluminum and aluminum alloy, and coarse grains, leading to a significant decrease in density, thermal diffusivity, and tensile strength. Figure 5 (a) and Figure 7 This is confirmed in (b).

[0100] Comparative Example 2 of this invention uses a conventional casting method to prepare copper-reinforced Al-6Si foam. Compared with Example 2, without turning on the rotary table and ultrasonic vibrator, there are many pores between copper and aluminum, resulting in poor venting and coarse grains in the aluminum and aluminum alloy. Figure 5 (b) and Figure 7 (b) It was confirmed that the density of the prepared composite material was only 2.10 g·cm³. -3 The thermal diffusivity and tensile strength are both smaller than those of Example 2.

[0101] Compared to Example 3, Comparative Example 3 did not include the additive cesium fluoroaluminate, but all other steps were the same as in Example 3. The role of the additive cesium fluoroaluminate is to remove the oxide scale on the copper surface, thereby improving the wettability between copper and aluminum and enhancing interfacial adhesion. Figure 5 (c) It can be seen that the copper surface of the composite material prepared in Comparative Example 3 has many black oxide scales. These oxide scales, acting as a barrier between aluminum and copper, inevitably affect the bonding between the foamed copper skeleton and the aluminum matrix. Table 1 shows that the density of the composite material prepared in Comparative Example 3 is only 2.15 g / cm³. -3 The thermal diffusivity and tensile strength decreased compared to Example 3.

[0102] Compared to Example 4, Comparative Example 4 did not include the Sn-Al20 master alloy, but all other steps were the same as in Example 4. The Sn-Al20 master alloy is mainly used to improve the wettability of aluminum and foamed copper because Sn and copper bond more easily. Because no Sn-Al20 master alloy was added, a large gap remained in the bond between aluminum and copper, and there was no Sn-Al20 connection between them. Their coefficients of thermal expansion differed significantly, leading to crack defects in the composite material, such as… Figure 5 As shown in (d), this results in a density of 2.11 g·cm³ for Comparative Example 4. -3 The thermal diffusivity and tensile strength were both reduced compared to Example 4.

[0103] Comparative Example 5 shows the performance indicators of as-cast industrial pure aluminum 1060 alloy. Compared with Example 1, its density, thermal diffusivity, and tensile strength are all lower, indicating that the copper-aluminum composite material of Example 1 has better performance. Comparative Example 6 shows the performance indicators of as-cast Al-6Si material. Compared with Example 2, each performance indicator is worse. This is because Example 2 uses the innovative technology described in this case, which improves the material's density, thermal diffusivity, and tensile strength. Comparative Example 7 shows the performance indicators of as-cast 4047 aluminum alloy. Compared with Example 3, its density, thermal diffusivity, and tensile strength are all lower, indicating that the copper-aluminum composite material of Example 3 has better performance. Comparative Example 8 shows the performance indicators of as-cast 6201 alloy. Compared with Example 4, its density, thermal diffusivity, and tensile strength are all lower, indicating that the copper-aluminum composite material of Example 4 has better performance. In summary, the composite materials prepared using Examples 1-4 of this invention have higher tensile strength than the corresponding cast aluminum materials. This is because the composite materials of Examples 1-4 have higher density and tensile strength than the corresponding matrix aluminum materials due to the combined effects of centrifugal force, ultrasonic degassing and grain refinement, as well as the addition of intermediate alloys and additives.

[0104] The difference between Comparative Example 9 and Example 3 lies in the selection of ultrasonic oscillation parameters. In the fully liquid state of molten aluminum, low-frequency, high-power (18kHz, 600W) oscillation was used, while in the liquid-solid coexistence temperature of aluminum, high-frequency, low-power (22kHz and 300W) oscillation was used. This resulted in inferior grain refinement and hydrogen removal / venting effects compared to Example 3, leading to a material density of only 2.35 g / cm³. -3 The strength is only 84.27 MPa, but due to the activation of ultrasonic oscillation, its thermal diffusivity is slightly less than that of Example 3. However, compared with Comparative Example 3, its thermal diffusivity is higher than that of Comparative Example 3 due to the good bonding interface between copper and aluminum.

[0105] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a foamed copper-reinforced aluminum-based composite material, characterized in that, Includes the following steps: S1: Immerse the foamed copper in the flux suspension and dry it to obtain pretreated foamed copper; S2: The aluminum matrix and the intermediate alloy are fused together, and the slag is removed to obtain a liquid alloy; the aluminum matrix is ​​selected from at least one of pure aluminum or cast aluminum alloy; the intermediate alloy is selected from one or both of Zn-Al alloy or Sn-Al alloy, and the intermediate alloy accounts for 2-10% of the total weight of the aluminum matrix, the intermediate alloy and the foamed copper; S3: Preheat the pretreated foamed copper to a temperature above the melting point of the alloy liquid; S4: Rotate the preheated foamed copper at a speed of 800~6000rpm, inject the alloy liquid, rotate for 2~5 minutes, so that the alloy liquid is thrown into the pores of the foamed copper by centrifugal force. S5: Apply ultrasound to the product obtained after step S4 to make hydrogen bubbles in the aluminum melt grow and escape. The frequency of the ultrasound is 20~22kHz and the power of the ultrasound is 200~500W. S6: Cooling. When the temperature drops to the solid-liquid coexistence temperature of the alloy liquid, adjust the frequency of the ultrasound to 18~20kHz and the power of the ultrasound to 500~1000W until it is fully formed. Then stop rotating to obtain the foamed copper reinforced aluminum matrix composite material.

2. The method for preparing a foamed copper-reinforced aluminum-based composite material as described in claim 1, characterized in that, The copper foam mentioned in step S1 has a pore size of 0.1~10mm, a porosity of 95~98%, and a bulk density of 0.1~0.8g / cm³. 3 .

3. The method for preparing a foamed copper-reinforced aluminum-based composite material as described in claim 1, characterized in that, The fluxing agent in step S1 is selected from one or a mixture of potassium fluoroaluminate or cesium fluoroaluminate; the soaking time in step S1 is 5 to 30 minutes; preferably, the weight ratio of the fluxing agent to water is 5 to 15:

100.

4. The method for preparing a foamed copper-reinforced aluminum-based composite material as described in claim 1, characterized in that, In step S2, the pure aluminum is selected from at least one of the following industrial pure aluminum grades: 1080, 1080A, 1070, 1070A, 1370, 1060, 1050, and 1050A. The cast aluminum alloy is selected from at least one of aluminum-silicon alloy, aluminum-magnesium alloy, or aluminum-zinc alloy. The intermediate alloy is selected from one or both of Zn-Al alloy or Sn-Al alloy. Preferably, the Zn-Al alloy or Sn-Al alloy contains 2-20% aluminum by weight.

5. The method for preparing a foamed copper-reinforced aluminum-based composite material as described in claim 1, characterized in that, The preparation steps of the alloy liquid in step S2 are as follows: heating pure aluminum or cast aluminum alloy to melt, adding intermediate alloy, holding at the temperature, and removing slag to obtain alloy liquid; preferably, the heating temperature is 650~750℃; preferably, the holding time is 30~60min.

6. The method for preparing a foamed copper-reinforced aluminum-based composite material as described in claim 1, characterized in that, The preheating temperature in step S3 is 650~850℃.

7. The method for preparing a foamed copper-reinforced aluminum-based composite material as described in claim 1, characterized in that, The frequency of the ultrasound in step S5 is 20~22kHz, the power of the ultrasound in step S5 is 200~500W, and the duration of the ultrasound in step S5 is 60~240s.

8. The method for preparing a foamed copper-reinforced aluminum-based composite material as described in claim 1, characterized in that, The frequency of the ultrasound in step S6 is 20~22kHz, the power of the ultrasound in step S6 is 200~500W, and the duration of the ultrasound in step S6 is 60~240s.

9. A foamed copper-reinforced aluminum-based composite material, characterized in that, It is prepared by the preparation method described in any one of claims 1 to 8.

10. The application of the foamed copper reinforced aluminum matrix composite material as described in claim 9 in the preparation of lightweight intelligent thermal management materials.

Images