Polymer-based porous metal composite material and preparation method thereof

Abstract

The invention relates to the field of porous metal materials, in particular to a polymer-based porous metal composite material and a preparation method thereof.The polymer-based porous metal composite material is composed of, by mass, 50-55 parts of a porous aluminum matrix, 20-25 parts of modified epoxy resin, 15-20 parts of modified carbon fibers, 4-6 parts of hollow glass microspheres and 6-8 parts of polyether-ether-ketone. According to the invention, through collaborative design of a special group grafting modified resin system and a multi-stage structure, and in combination with a chemical-physical double-effect interface strengthening process and stepped precise curing control, the problem of collaboration of light weight and high strength in a light-weight composite material is solved. Compared with the prior art, on the premise of keeping ultra-low density, remarkable improvement of heat resistance, interface reliability and multifunctionality is achieved, and the ultra-low density composite material perfectly adapts to the field of high-end equipment such as light-weight battery boxes of new energy automobiles and aerospace high-temperature-resistant components and has wide industrialization prospects.

Description

Technical Field

[0001] The present invention relates to the field of porous metal materials, and in particular to a polymer-based porous metal composite material and a preparation method thereof. Background Art

[0002] Polymer-based porous metal composites are lightweight functional materials formed by a porous metal skeleton as the supporting structure and a polymer resin system filling the pores. Their core value lies in the synergistic mechanical properties of metals and the multifunctional characteristics of the resin-filler system.

[0003] In the existing technology, polymer-based porous metal composite materials prepared by traditional processes cannot achieve both lightweight and high strength due to stress concentration caused by homogeneous pores and insufficient resin filling rate. Secondly, the shear strength of the metal-resin interface after silane coupling agent treatment is low, and the strength decays in a humid and hot environment due to reliance on physical adsorption, resulting in serious lack of interface reliability and inability to meet dynamic load scenarios such as new energy vehicle battery boxes. In addition, due to component design defects in the existing technology, although a high filler amount can improve thermal conductivity, it causes embrittlement, and the pore structure destroys the continuity of the metal phase and restricts the electromagnetic shielding effectiveness, resulting in poor multifunctional synergy.

[0004] Therefore, according to the above-mentioned related technologies, there is an urgent need to develop a polymer-based porous metal composite material and a preparation method thereof. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to propose a polymer-based porous metal composite material and a preparation method thereof to solve the problems in the prior art of difficulty in balancing light weight and high strength, poor interface reliability and poor multifunctional synergy.

[0006] Based on the above objectives, the present invention provides a polymer-based porous metal composite material and a preparation method thereof.

[0007] A polymer-based porous metal composite material, comprising the following components in parts by mass: 50-55 parts of a porous aluminum matrix, 20-25 parts of a modified epoxy resin, 15-20 parts of modified carbon fibers, 4-6 parts of hollow glass microspheres, and 6-8 parts of polyetheretherketone;

[0008] The modified epoxy resin is a maleimide-modified epoxy resin;

[0009] The modified carbon fiber is a carbon fiber modified with a phosphate coupling agent.

[0010] Preferably, the porous aluminum substrate is prepared as follows:

[0011] Step A1: adding aluminum powder and polymethyl methacrylate microspheres into anhydrous ethanol solvent, ball milling and mixing, grinding for 1-3 hours at a speed of 100-300 rpm to obtain a slurry;

[0012] Step A2: Pour the slurry into a mold, heat it to 70-90°C, pressurize it to 180-220 MPa, maintain the pressure for 8-12 minutes, place it in a tube furnace, introduce argon, heat it to 430-470°C, maintain it for 1-3 hours, then reduce the pressure to -0.01 Pa, heat it to 600-800°C, maintain it for 50-70 minutes, and cool it to 80-120°C to obtain porous aluminum;

[0013] Step A3: placing the porous aluminum in a 5 wt % sodium hydroxide solution, heating to 20-40° C., shaking for 3-7 minutes, rinsing with deionized water until neutral, then immersing in a 10 wt % HCl solution, heating to 20-40° C., shaking for 3-7 minutes, and rinsing with deionized water to obtain roughened porous aluminum;

[0014] Step A4: placing the roughened porous aluminum in an ion chamber under a mixed atmosphere of argon and oxygen at a radio frequency power of 300-400W for 4-6 minutes, adding a 2w% titanate ethanol solution, reacting for 8-12 minutes, and drying and curing to obtain a porous aluminum substrate;

[0015] By treating porous aluminum with titanate and plasma, the surface oxygen content is increased, generating nano-scale Al-OH active sites. The titanate hydrolyzes to form Ti-O-Al chemical bonds, which then react with the ester group of the resin to construct a metal-coupling agent-resin triple bond network, improving its environmental durability.

[0016] Preferably, the mass ratio of the aluminum powder to the polymethyl methacrylate microspheres in step A1 is 1:0.24-0.26;

[0017] In step A3, the mass ratio of the porous aluminum, sodium hydroxide solution, and HCl solution is 1:14-16:14-16;

[0018] The volume ratio of argon to oxygen in step A4 is 8:2;

[0019] The mass ratio of the roughened porous material to the titanate ethanol solution in step A4 is 1:4-6.

[0020] Preferably, the modified epoxy resin is prepared as follows:

[0021] Under nitrogen atmosphere, add bisphenol epoxy resin and bismaleimide monomer into xylene solvent, stir and dissolve, heat to 75-85℃, react for 20-40min, after the reaction is complete, cool to 30-40℃, add curing agent 4,4'-diaminodiphenyl sulfone, stir for 8-12min, speed 100-200rpm, then add fumed silica, shear for 4-6min, speed

[0022] 4000-6000rpm,得改性环氧树脂;

[0023] A rigid imide ring is introduced into the epoxy main chain to form a cross-linked network through a ring-opening reaction. The conjugated structure of the imide ring inhibits the thermal motion of the molecular chain, thereby increasing the glass transition temperature. The imide group forms an Al-ON coordination bond with the aluminum surface oxide layer, thereby improving the interfacial shear strength.

[0024] Preferably, the mass ratio of the bisphenol epoxy resin, bismaleimide monomer, curing agent and fumed silica is 1:0.07-0.09:0.24-0.26:0.04-0.06.

[0025] Preferably, the modified carbon fiber preparation steps are as follows:

[0026] Step B1: immerse the carbon fiber in an acetone solvent, heat it to 20-30°C, ultrasonicate for 20-40 minutes, place it in a drying oven, heat it to 100-120°C, dry it for 50-70 minutes, take it out, add a 3wt% ethanol solution of vinyl dimethyl phosphate coupling agent, heat it to 45-55°C, react for 20-40 minutes, and dry it after the reaction is complete to obtain pretreated carbon fiber;

[0027] Step B2: Under a nitrogen atmosphere, the pretreated carbon fiber is placed in an oven, heated to 110-130°C, cured for 50-70 minutes, cooled to 20-30°C, washed with deionized water, and dried to obtain the modified carbon fiber;

[0028] By using vinyl dimethyl phosphate to construct a POC covalent bond on the carbon fiber surface, it decomposes into polyphosphoric acid when exposed to heat, catalyzing the resin into carbon and improving its flame retardancy. At the same time, the hydrolysis energy of the PO-Al bond is much higher than that of the traditional Si-O-Al bond, which can improve its strength in high humidity environments. In addition, the imide group and the phosphate produce a synergistic effect to form a PON charge transfer complex, which enhances the interface strength. The carbon fiber is changed by the magnetic field so that the axial deviation of the fiber is ≤15°, and the fiber is oriented along the direction of the principal stress to form a continuous heat conduction path.

[0029] Preferably, the mass ratio of the carbon fiber to the ethanol solution of vinyl dimethyl phosphate coupling agent in step B1 is 1:9.5-10.5.

[0030] A method for preparing a polymer-based porous metal composite material, the preparation steps are as follows:

[0031] Step S1: adding a porous aluminum substrate to a modified epoxy resin, heating to 30-50°C, evacuating to -0.095 MPa, reacting for 15-25 minutes, adding polyetheretherketone, hollow glass microspheres, and modified carbon fibers, heating to 70-90°C, stirring and reacting for 8-12 minutes at a speed of 200-400 rpm, placing in an autoclave, pressurizing to 4-6 MPa, heating to 70-90°C, maintaining the pressure for 10-20 minutes, transferring to a magnetic field device, and applying a static magnetic field of 1.1-1.3 T axially for 8-12 minutes to obtain a prepreg;

[0032] Step S2: adding the impregnated article to the mold, heating to 70-90°C, pressurizing to 0.8-1.2 MPa, reacting for 50-70 minutes, heating to 170-190°C, pressurizing to 8-12 MPa, reacting for 50-70 minutes, releasing the pressure to 0 MPa, heating to 195-205°C, reacting for 50-70°C, cooling to 70-80°C, and after the reaction is complete, placing in an oven, heating to 140-160°C, and static annealing for 100-140 minutes to obtain a polymer-based porous metal composite material;

[0033] The hierarchical pore structure of the porous aluminum matrix allows macropores to serve as channels for resin flow, increasing its filling rate. Its surface can lock hollow glass microspheres, increasing the overall density of the material and compensating for the difference in thermal expansion between the resin and aluminum. At the same time, the microspheres absorb energy when they break, improving impact resistance. Furthermore, through multi-stage impregnation and staged curing reactions, fiber displacement caused by high pressure is avoided, internal stress can be eliminated, and the pores are closed and densified.

[0034] Preferably, the mass ratio of the porous aluminum matrix, modified epoxy resin, polyetheretherketone and hollow glass microspheres in step S1 is 1:0.44-0.46:0.12-0.13:0.08-0.1:0.32-0.33.

[0035] Beneficial effects of the present invention:

[0036] This invention provides a polymer-based porous metal composite material and its preparation method. By integrating a resin system modified by grafting special groups with a multi-stage structure design, combined with a chemical-physical dual-effect interface strengthening process and step-by-step precision curing control, this breakthrough addresses the challenge of balancing strength, function, and durability in lightweight composite materials. Compared with existing technologies, this material achieves significant improvements in heat resistance, interface reliability, and multifunctionality while maintaining ultra-low density. It is ideally suited for high-end equipment such as lightweight battery boxes for new energy vehicles and high-temperature-resistant components for aerospace applications, and has broad prospects for industrialization. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 This is a preparation process flow chart of a method for preparing a polymer-based porous metal composite material in the present invention;

[0039] Figure 2 This is a SEM micrograph of the cross section of the composite material of the embodiment of the present invention. DETAILED DESCRIPTION

[0040] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to specific embodiments.

[0041] 实施例1:多孔铝基体制备步骤:

[0042] S1: 100 g of aluminum powder and 24 g of polymethyl methacrylate microspheres were added to 200 mL of anhydrous ethanol solvent, and the mixture was ball-milled for 1 h at a speed of 300 rpm to obtain a slurry;

[0043] S2: Pour 100 g of the slurry into a mold, heat it to 70°C, pressurize it to 220 MPa, and maintain the pressure for 8 minutes. After the pressure is maintained, put it into a tube furnace, introduce argon, heat it to 470°C, maintain it for 1 hour, then reduce the pressure to -0.01 Pa, heat it to 800°C, maintain it for 50 minutes, and cool it down to 120°C to obtain porous aluminum;

[0044] S3: 100 g of porous aluminum was placed in 1400 g of 5 wt% sodium hydroxide solution, heated to 20° C., shaken for 7 min, rinsed with deionized water until neutral, and then immersed in 1400 g of 10 wt% HCl solution, heated to 20° C., shaken for 7 min, and rinsed with deionized water to obtain roughened porous aluminum;

[0045] S4: In a mixed atmosphere of argon and oxygen, 100 g of roughened porous aluminum was placed in an ion chamber with a radio frequency power of 300 W for 6 min, 400 g of 2 w% t titanate ethanol solution was added, and the reaction was carried out for 8 min. After the reaction was completed, the aluminum was dried and solidified to obtain a porous aluminum matrix.

[0046] 实施例2:多孔铝基体制备步骤:

[0047] S1: 100 g of aluminum powder and 25 g of polymethyl methacrylate microspheres were added to 200 mL of anhydrous ethanol solvent, and the mixture was ball-milled for 2 h at a speed of 200 rpm to obtain a slurry;

[0048] S2: Pour 100 g of the slurry into a mold, heat it to 80°C, pressurize it to 200 MPa, and maintain the pressure for 10 minutes. After the pressure is maintained, put it into a tube furnace, introduce argon, heat it to 450°C, maintain it for 2 hours, then reduce the pressure to -0.01 Pa, heat it to 700°C, maintain it for 60 minutes, and cool it down to 100°C to obtain porous aluminum;

[0049] S3: 100 g of porous aluminum was placed in 1500 g of 5 wt% sodium hydroxide solution, heated to 30° C., shaken for 5 min, rinsed with deionized water until neutral, and then immersed in 1500 g of 10 wt% HCl solution, heated to 30° C., shaken for 5 min, and rinsed with deionized water to obtain roughened porous aluminum;

[0050] S4: In a mixed atmosphere of argon and oxygen, 100 g of roughened porous aluminum was placed in an ion chamber with a radio frequency power of 350 W for 5 min, 500 g of 2 w% t titanate ethanol solution was added, and the reaction was carried out for 10 min. After the reaction was completed, the aluminum was dried and solidified to obtain a porous aluminum matrix.

[0051] 实施例3:多孔铝基体制备步骤:

[0052] S1: 100 g of aluminum powder and 26 g of polymethyl methacrylate microspheres were added to 200 mL of anhydrous ethanol solvent, and the mixture was ball-milled for 3 h at a speed of 100 rpm to obtain a slurry;

[0053] S2: Pour 100 g of the slurry into a mold, heat it to 90°C, pressurize it to 180 MPa, and maintain the pressure for 12 minutes. After the pressure is maintained, put it into a tube furnace, introduce argon, heat it to 430°C, and maintain it for 3 hours. Then reduce the pressure to -0.01 Pa, heat it to 600°C, maintain it for 70 minutes, and cool it down to 80°C to obtain porous aluminum.

[0054] S3: 100 g of porous aluminum was placed in 1600 g of 5 wt% sodium hydroxide solution, heated to 40° C., shaken for 3 min, rinsed with deionized water until neutral, and then immersed in 1600 g of 10 wt% HCl solution, heated to 40° C., shaken for 3 min, and rinsed with deionized water to obtain roughened porous aluminum;

[0055] S4: In a mixed atmosphere of argon and oxygen, 100 g of roughened porous aluminum was placed in an ion chamber with a radio frequency power of 400 W for 4 min. 600 g of 2 w% t titanate ethanol solution was added and reacted for 12 min. After the reaction was completed, the aluminum was dried and solidified to obtain a porous aluminum matrix.

[0056] 实施例4:改性环氧树脂制备步骤:

[0057] Under a nitrogen atmosphere, 100 g of bisphenol epoxy resin and 7 g of bismaleimide monomer were added to 150 mL of xylene solvent, stirred and dissolved, heated to 75 ° C, reacted for 40 minutes, and after the reaction was completed, cooled to 30 ° C, added 24 g of curing agent 4,4'-diaminodiphenyl sulfone, stirred for 8 minutes at a speed of 200 rpm, and then added fumed silica. Sheared for 4 minutes at a speed of 6000 rpm to obtain a modified epoxy resin.

[0058] 实施例5:改性环氧树脂制备步骤:

[0059] Under a nitrogen atmosphere, 100 g of bisphenol epoxy resin and 8 g of bismaleimide monomer were added to 150 mL of xylene solvent, stirred and dissolved, heated to 80 ° C, reacted for 30 minutes, and after the reaction was completed, cooled to 35 ° C, added 25 g of curing agent 4,4'-diaminodiphenyl sulfone, stirred for 10 minutes at a speed of 150 rpm, and then added 5 g of fumed silica. Sheared for 5 minutes at a speed of 5000 rpm to obtain a modified epoxy resin.

[0060] 实施例6:改性环氧树脂制备步骤:

[0061] Under a nitrogen atmosphere, 100 g of bisphenol epoxy resin and 9 g of bismaleimide monomer were added to 150 mL of xylene solvent, stirred and dissolved, heated to 85 ° C, reacted for 20 minutes, and after the reaction was completed, cooled to 40 ° C, added 26 g of curing agent 4,4'-diaminodiphenyl sulfone, stirred for 8 minutes at a speed of 200 rpm, and then added 6 g of fumed silica. Sheared for 4 minutes at a speed of 6000 rpm to obtain a modified epoxy resin.

[0062] 实施例7:改性碳纤维制备步骤:

[0063] S1: 100 g of carbon fiber was immersed in 200 mL of acetone solvent, heated to 20 ° C, ultrasonicated for 40 min, placed in a drying oven, heated to 100 ° C, dried for 70 min, taken out, added to 950 g of 3 wt% vinyl dimethyl phosphate coupling agent ethanol solution, heated to 45 ° C, reacted for 40 min, and dried to obtain pretreated carbon fiber;

[0064] S2: Under a nitrogen atmosphere, 100 g of pretreated carbon fiber was placed in an oven, heated to 110°C, cured for 70 min, cooled to 20°C, washed with deionized water, and dried to obtain modified carbon fiber.

[0065] 实施例8:改性碳纤维制备步骤:

[0066] S1: 100g of carbon fiber was immersed in 200mL of acetone solvent, heated to 25°C, ultrasonicated for 30min, placed in a drying oven, heated to 100°C, dried for 70min, taken out, added to 1000g of 3wt% ethanol solution of vinyl dimethyl phosphate coupling agent, heated to 50°C, reacted for 30min, and dried to obtain pretreated carbon fiber;

[0067] S2: Under a nitrogen atmosphere, 100 g of pretreated carbon fiber was placed in an oven, heated to 120°C, cured for 60 min, cooled to 25°C, washed with deionized water, and dried to obtain modified carbon fiber.

[0068] 实施例9:改性碳纤维制备步骤:

[0069] S1: 100 g of carbon fiber was immersed in 200 mL of acetone solvent, heated to 30 ° C, ultrasonicated for 20 min, placed in a drying oven, heated to 120 ° C, dried for 50 min, taken out, added to 1050 g of 3 wt% vinyl dimethyl phosphate coupling agent ethanol solution, heated to 55 ° C, reacted for 20 min, and dried to obtain pretreated carbon fiber;

[0070] S2: Under a nitrogen atmosphere, 100 g of pretreated carbon fiber was placed in an oven, heated to 130°C, cured for 50 min, cooled to 30°C, washed with deionized water, and dried to obtain modified carbon fiber.

[0071] Example 10: Preparation method of a polymer-based porous metal composite material

[0072] S1: Add 100 g of porous aluminum substrate to 44 g of modified epoxy resin, heat to 30 ° C, evacuate to -0.095 MPa, react for 25 min, add 12 g of polyetheretherketone, 8 g of hollow glass microspheres and 32 g of modified carbon fiber, heat to 70 ° C, stir and react for 12 min, rotate at 200 rpm, place in an autoclave, pressurize to 6 MPa, heat to 70 ° C, maintain pressure for 20 min, transfer to a magnetic field device, apply a 1.1 T static magnetic field in the axial direction, and maintain for 12 min to obtain an impregnated part;

[0073] S2: Add 100g of the impregnated part into the mold, heat it to 70℃, pressurize it to 1.2MPa, react for 50min, heat it to 190℃, pressurize it to 8MPa, react for 70min, release the pressure to 0MPa, heat it to 195℃, react at 70℃, cool it to 70℃, put it into an oven, heat it to 160℃, and statically anneal it for 100min to obtain a polymer-based porous metal composite material.

[0074] Example 11: Preparation method of a polymer-based porous metal composite material

[0075] S1: Add 100 g of porous aluminum substrate to 45 g of modified epoxy resin, heat to 40 ° C, evacuate to -0.095 MPa, react for 20 min, add 12.5 g of polyetheretherketone, 9 g of hollow glass microspheres and 32.5 g of modified carbon fiber, heat to 80 ° C, stir and react for 10 min, rotate at 300 rpm, place in an autoclave, pressurize to 5 MPa, heat to 80 ° C, maintain pressure for 15 min, transfer to a magnetic field device, apply a 1.2 T static magnetic field in the axial direction, and maintain for 10 min to obtain an impregnated part;

[0076] S2: Add 100g of the impregnated part into the mold, heat it to 80℃, pressurize it to 1MPa, react for 60min, heat it to 180℃, pressurize it to 10MPa, react for 60min, release the pressure to 0MPa, heat it to 200℃, react for 60℃, cool it to 75℃, and after the reaction is complete, put it into an oven, heat it to 150℃, and statically anneal it for 120min to obtain a polymer-based porous metal composite material.

[0077] Example 12: Preparation method of a polymer-based porous metal composite material

[0078] S1: Add 100 g of porous aluminum substrate to 46 g of modified epoxy resin, heat to 50 ° C, evacuate to -0.095 MPa, react for 15 min, add 13 g of polyetheretherketone, 10 g of hollow glass microspheres and 33 g of modified carbon fiber, heat to 90 ° C, stir and react for 8 min, rotate at 400 rpm, place in an autoclave, pressurize to 4 MPa, heat to 90 ° C, maintain pressure for 10 min, transfer to a magnetic field device, apply a 1.3 T static magnetic field in the axial direction, and maintain for 8 min to obtain an impregnated part;

[0079] S2: Add 100g of the impregnated part into the mold, heat it to 90℃, pressurize it to 0.8MPa, react for 70min, heat it to 170℃, pressurize it to 12MPa, react for 50min, release the pressure to 0MPa, heat it to 205℃, react by 50℃, cool it to 80℃, after the reaction is complete, put it into an oven, heat it to 140℃, and statically anneal it for 140min to obtain a polymer-based porous metal composite material.

[0080] Comparative Example 1:

[0081] Compared with Example 10, this comparative example does not perform pressure impregnation in the preparation process S1 of a polymer-based porous metal composite material. The remaining steps and parameters are the same and will not be repeated in this comparative example. Finally, a polymer-based porous metal composite material is obtained.

[0082] Comparative Example 2:

[0083] Compared with Example 10, this comparative example only replaces "modified epoxy resin" with "epoxy resin", and the remaining steps and parameters are the same, which will not be repeated in this comparative example. Finally, a polymer-based porous metal composite material is obtained.

[0084] Comparative Example 3:

[0085] Compared with Example 10, this comparative example only replaces the "phosphate coupling agent" with the "KH-550 silane coupling agent", and the remaining steps and parameters are the same, which will not be repeated in this comparative example. Finally, a polymer-based porous metal composite material is obtained.

[0086] Comparative Example 4:

[0087] Compared with Example 10, in the preparation process S2 of a polymer-based porous metal composite material, the pressure is 10 MPa, the temperature is kept constant at 170°C, and the curing is carried out for 120 minutes. The remaining steps and parameters are the same and will not be repeated in this comparative example. Finally, a polymer-based porous metal composite material is obtained.

[0088] Performance testing:

[0089] 密度测试:

[0090] According to the GB / T1033.3-2010 test standard, an XS204 electronic density meter was used to cut the composite materials of Examples 10-12 and Comparative Examples 1-4 into 25×25×5 mm cubes, add them to anhydrous ethanol, heat to 25° C., and measure three times to obtain the average value.

[0091] 阻燃性测试:

[0092] With reference to the UL94-2018 test standard, an FTT cone calorimeter was used to cut the composite materials of Examples 10-12 and Comparative Examples 1-4 into 125×13×3 mm pieces respectively. The composite materials were burned vertically for 10 seconds, and the self-extinguishing time and the molten droplet were recorded.

[0093] Table 1

[0094]

[0095]

[0096] 拉伸强度测试:

[0097] With reference to the GB / T 1040.2-2006 test standard, a universal material testing machine was used to cut the composite materials of Examples 10-12 and Comparative Examples 1-4 into 50×10×2 mm pieces. The pieces were placed in the testing machine at a tensile rate of 2 mm / min and heated to 23°C and 50% RH to test the tensile strength.

[0098] 界面剪切强度:

[0099] Referring to the ASTM D3165-2014 test standard, a single fiber strength tester was used to take the composite materials of Examples 10-12 and Comparative Examples 1-4, respectively. A single carbon fiber with a length of 25 mm and a resin-embedded section of 10 mm was separated from the composite materials and placed in the tester at a loading rate of 1 mm / min. The shear strength was recorded.

[0100] 盐雾老化测试:

[0101] With reference to the GB / T 10125-2021 test standard, an S450 salt spray chamber was used. The composite materials of Examples 10-12 and Comparative Examples 1-4 were respectively cut into 50×10×2 mm pieces. The samples were heated to 35°C and sprayed with 5% NaCl solution for 240 h. The samples were rinsed with deionized water and dried. The samples were placed in a testing machine at a tensile rate of 2 mm / min. The samples were heated to 23°C and in a 50% RH environment. The tensile strength and strength retention were tested as follows:

[0102] Table 2

[0103]

[0104] 导热系数:

[0105] According to the ASTM E1461-2013 test standard, a laser flash spectrometer was used to cut the composite materials of Examples 10-12 and Comparative Examples 1-4 into Φ12.7×2 mm discs, and graphite was sprayed on both sides under a nitrogen atmosphere at an initial temperature of 25°C and an end temperature of 200°C.

[0106] 热变形温度:

[0107] With reference to the GB / T 1634.2-2019 test standard, a Ceast-HDT-3-VICAT instrument was used to take 1.0 g of the composite materials of Examples 10-12 and Comparative Examples 1-4, respectively. The load was 1.82 MPa, the heating rate was 120°C / h, the bending deformation of the sample was 0.34 mm, and the heat deformation temperature was recorded.

[0108] Table 3

[0109] project 200℃导热系数(W / m·K) Heat deformation temperature (℃) Example 10 12.0 252 Example 11 12.2 255 Example 12 11.8 250 Comparative Example 1 5.4 240 Comparative Example 2 6.5 178 Comparative Example 3 10.3 243 Comparative Example 4 8.8 230

[0110] Data Analysis:

[0111] As can be seen from Tables 1-3, the polymer-based porous metal composite material prepared by the present invention has better synergy between lightweight and high strength, higher interfacial shear strength, better strength retention after salt spray aging, and more outstanding flame retardancy, thermal conductivity at 200°C, and heat deformation temperature;

[0112] In Comparative Example 1, since no pressure was applied during the impregnation stage, the resin filling rate was insufficient and the pore structure was not fully densified. Its density was the lowest, but the tensile strength and thermal conductivity were significantly reduced. The reason was that the resin could not fully fill the hierarchical pores of the porous aluminum matrix due to the lack of pressure. The macropores did not serve as flow channels, and the micropores did not lock the hollow glass microspheres. As a result, the residual pores became stress concentration points, weakening the continuity of the metal skeleton. At the same time, the carbon fibers were randomly distributed in the absence of magnetic field orientation and could not form a continuous thermal conductive network along the principal stress direction. In addition, the low density was due to the fact that the pores were not filled with the resin-microsphere composite, which was actually a structural defect rather than effective lightweighting.

[0113] Comparative Example 2 does not use maleimide-modified epoxy resin, resulting in deterioration of interfacial bonding and heat resistance, and its tensile strength, heat distortion temperature and flame retardancy are all reduced. The reason is that the lack of maleimide groups cannot form Al-ON coordination bonds with the aluminum surface oxide layer, and the ordinary epoxy resin has a low crosslinking density. The lack of rigid imide rings leads to increased thermal motion of the molecular chain, thereby weakening the crosslinking network. In addition, the PON charge transfer complex of the imide nitrogen element and the phosphate in the modified resin is the key to flame retardancy, and ordinary resin cannot catalyze carbonization;

[0114] In Comparative Example 3, since the phosphate coupling agent was replaced with KH-550 silane coupling agent, the interface failed in a hot and humid environment, and its strength retention and flame retardancy after salt spray were reduced. This is because the Si-O-Al bond of the silane coupling agent has low hydrolysis energy and is easily broken in a hot and humid environment. In addition, the silane coupling agent has no thermal decomposition catalytic ability, resulting in the failure of the flame retardant mechanism. In addition, it is unable to form a PON complex with the resin imide group, and the interface toughening effect is lost.

[0115] Comparative Example 4 adopts a single-stage 170°C, 10MPa constant temperature curing and does not implement step-by-step precise curing control, resulting in internal stress accumulation and insufficient pore closure. Its heat deformation temperature, thermal conductivity and strength retention rate all decrease. The reason is that the high-pressure and high-temperature one-step curing causes the resin to shrink rapidly, generating local stress and inducing microcracks. In addition, there is a lack of a 70-90°C low-pressure pre-curing stage, resulting in insufficient resin fluidity and uninitial pore filling. At the same time, the 170-190°C medium-pressure stage is skipped, and the graded densification is interrupted, resulting in discontinuous heat conduction paths and insufficient pore closure. In addition, static annealing at 140-160°C is not performed, and residual stress cannot be released.

[0116] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention is limited to these examples. Within the scope of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0117] The present application is intended to cover all such alternatives, modifications, and variations as fall within the broad scope of the appended claims. Accordingly, any and all such alternatives, modifications, equivalents, improvements and the like are intended to be encompassed by the present application.

Claims

1. A polymer-based porous metal composite material, characterized in that: The invention is composed of the following components in parts by mass: 50-55 parts of porous aluminum matrix, 20-25 parts of modified epoxy resin, 15-20 parts of modified carbon fiber, 4-6 parts of hollow glass microspheres, and 6-8 parts of polyetheretherketone; The modified epoxy resin is a maleimide-modified epoxy resin; The modified carbon fiber is a carbon fiber modified with a phosphate coupling agent.

2. The polymer-based porous metal composite material according to claim 1, characterized in that: The porous aluminum substrate preparation steps are as follows: Step A1: adding aluminum powder and polymethyl methacrylate microspheres into anhydrous ethanol solvent, ball milling and mixing, grinding for 1-3 hours at a speed of 100-300 rpm to obtain a slurry; Step A2: Pour the slurry into a mold, heat it to 70-90°C, pressurize it to 180-220 MPa, maintain the pressure for 8-12 minutes, place it in a tube furnace, introduce argon, heat it to 430-470°C, maintain it for 1-3 hours, then reduce the pressure to -0.01 Pa, heat it to 600-800°C, maintain it for 50-70 minutes, and cool it to 80-120°C to obtain porous aluminum; Step A3: placing the porous aluminum in a 5 wt % sodium hydroxide solution, heating to 20-40° C., shaking for 3-7 minutes, rinsing with deionized water until neutral, then immersing in a 10 wt % HCl solution, heating to 20-40° C., shaking for 3-7 minutes, and rinsing with deionized water to obtain roughened porous aluminum; Step A4: Place the roughened porous aluminum in an ion chamber under a mixed atmosphere of argon and oxygen, treat with a radio frequency power of 300-400W for 4-6 minutes, add 2w%t titanate ethanol solution, react for 8-12 minutes, and after the reaction is completed, dry and solidify to obtain a porous aluminum matrix.

3. The polymer-based porous metal composite material according to claim 2, characterized in that: The mass ratio of aluminum powder to polymethyl methacrylate microspheres in step A1 is 1:0.24-0.26; In step A3, the mass ratio of the porous aluminum, sodium hydroxide solution, and HCl solution is 1:14-16:14-16; The volume ratio of argon to oxygen in step A4 is 8:2; The mass ratio of the roughened porous material to the titanate ethanol solution in step A4 is 1:4-6.

4. The polymer-based porous metal composite material according to claim 1, characterized in that: The modified epoxy resin preparation steps are as follows: Under a nitrogen atmosphere, bisphenol epoxy resin and bismaleimide monomer are added to a xylene solvent, stirred and dissolved, heated to 75-85°C, reacted for 20-40 minutes, and after the reaction is complete, cooled to 30-40°C, and a curing agent 4,4'-diaminodiphenyl sulfone is added. The mixture is stirred for 8-12 minutes at a speed of 100-200 rpm, and then fumed silica is added. The mixture is sheared for 4-6 minutes at a speed of 4000-6000 rpm to obtain a modified epoxy resin.

5. The polymer-based porous metal composite material according to claim 4, characterized in that: The mass ratio of the bisphenol epoxy resin, bismaleimide monomer, curing agent and fumed silica is 1:0.07-0.09:0.24-0.26:0.04-0.

06.

6. The polymer-based porous metal composite material according to claim 1, characterized in that: The modified carbon fiber preparation steps are as follows: Step B1: immerse the carbon fiber in an acetone solvent, heat it to 20-30°C, ultrasonicate for 20-40 minutes, place it in a drying oven, heat it to 100-120°C, dry it for 50-70 minutes, take it out, add a 3wt% ethanol solution of vinyl dimethyl phosphate coupling agent, heat it to 45-55°C, react for 20-40 minutes, and dry it after the reaction is complete to obtain pretreated carbon fiber; Step B2: Under a nitrogen atmosphere, the pretreated carbon fiber is placed in an oven, heated to 110-130° C., cured for 50-70 minutes, cooled to 20-30° C., washed with deionized water, and dried to obtain modified carbon fiber.

7. The polymer-based porous metal composite material according to claim 6, characterized in that: The mass ratio of the carbon fiber to the ethanol solution of vinyl dimethyl phosphate coupling agent in step B1 is 1:9.5-10.

5.

8. The method for preparing a polymer-based porous metal composite material according to any one of claims 1 to 7, characterized in that: The preparation steps are as follows: Step S1: adding a porous aluminum substrate to a modified epoxy resin, heating to 30-50°C, evacuating to -0.095 MPa, reacting for 15-25 minutes, adding polyetheretherketone, hollow glass microspheres, and modified carbon fibers, heating to 70-90°C, stirring and reacting for 8-12 minutes at a speed of 200-400 rpm, placing in an autoclave, pressurizing to 4-6 MPa, heating to 70-90°C, maintaining the pressure for 10-20 minutes, transferring to a magnetic field device, and applying a static magnetic field of 1.1-1.3 T axially for 8-12 minutes to obtain a prepreg; Step S2: Add the impregnated part to the mold, heat it to 70-90°C, pressurize it to 0.8-1.2MPa, react for 50-70min, heat it to 170-190°C, pressurize it to 8-12MPa, react for 50-70min, release the pressure to 0MPa, heat it to 195-205°C, react for 50-70°C, cool it to 70-80°C, after the reaction is complete, place it in an oven, heat it to 140-160°C, and statically anneal it for 100-140min to obtain a polymer-based porous metal composite material.

9. The method for preparing a polymer-based porous metal composite material according to claim 8, characterized in that: The mass ratio of the porous aluminum matrix, modified epoxy resin, polyetheretherketone, hollow glass microspheres and modified carbon fiber in step S1 is 1:0.44-0.46:0.12-0.13:0.08-0.1:0.32-0.33.

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