Preparation method of carbon fiber reinforced aluminum / glass bead composite metal material

Abstract

The invention relates to a preparation method of a carbon fiber reinforced aluminum / glass bead composite metal material. According to the method, nickel-plated carbon fibers are added into aluminum / glass bead powder turbid liquid in a stirring state, and then hot pressed sintering is performed in a graphite mold, so that nickel and aluminum on the surfaces of the nickel-plated carbon fibers tend to form a continuous and uniform Al3Ni thin-film-shaped interface layer at an interface, generation of an Al4C3 brittle phase is hindered, and the performance of the nickel-plated carbon fibers is improved. And the transition of the load from the matrix to the carbon fiber is realized. The proportion of the nickel-plated carbon fibers, the aluminum powder and the glass beads can be properly adjusted according to different purposes, and the material obtained after hot pressing sintering is uniform in component distribution and excellent in performance.

Description

Technical Field

[0001] This invention relates to the field of metal composite materials, and specifically to a method for preparing a carbon fiber reinforced aluminum / glass microsphere composite metal material. Background Technology

[0002] With the rapid development of aerospace equipment, marine engineering, and defense technology, military protection systems are facing unprecedented performance challenges. Taking armor structures and transport protection materials as examples, their core requirements have evolved from simple penetration resistance to multimodal dynamic energy dissipation capabilities. Especially for military equipment facing extreme service conditions such as mechanical vibration (20-2000Hz), high-g impacts (≥100g / ms), and complex inertial loads (lateral / pitch ±30°), traditional protective structures have revealed significant shortcomings due to the high frequency of transport and long storage periods. Statistics show that approximately 37% of damage during equipment transport is caused by multidimensional vibration coupling effects, and the failure rate of electronic devices due to extreme impacts is as high as 21%. This highlights the strategic value of developing new composite protective materials.

[0003] Based on this, cutting-edge materials science has proposed a multi-gradient structural solution—aluminum-based composite foam. Its innovation lies in overcoming the limitations of traditional solid materials' single-phase energy absorption by introducing a pre-fabricated controllable porous structure of hollow microspheres (porosity adjustable from 30-65%). Experimental verification shows that this material exhibits excellent strain rate strengthening effect in quasi-static compression tests, possesses a long compression plateau, and has strong energy absorption capacity. Patent CN 115305377B, "A Method for Preparing Aluminum-Based Porous Hollow Glass Microsphere Porous Composite Material," discloses a method for preparing a porous composite material using 2024 aluminum alloy as the matrix and hollow glass microspheres as the reinforcement. While this technology achieves material lightweighting through the combination of the aluminum alloy matrix and microspheres, the glass microspheres are inherently brittle ceramic materials, making them prone to localized crushing and breakage under compressive loads, limiting further improvements in peak strength and energy absorption capacity. Summary of the Invention

[0004] The purpose of this invention is to address the limitations of single-glass hollow microsphere reinforced aluminum matrix composites, specifically the problem that simply increasing the wall thickness or reducing the particle size to improve the composite strength leads to a decrease in porosity and an increase in density. This invention proposes a method for preparing nickel-plated carbon fiber reinforced aluminum / glass microsphere composite materials. This method involves adding nickel-plated carbon fiber to a suspension of aluminum / glass microsphere powder under stirring, followed by hot-pressing and sintering in a graphite mold. This causes the nickel and aluminum in the nickel-plated carbon fiber to tend to form a continuous and uniform Al3Ni thin film at the interface, thereby hindering the formation of the brittle Al4C3 phase and achieving a smooth transition of load from the matrix to the carbon fiber. This invention allows for appropriate adjustment of the ratio of nickel-plated carbon fiber, aluminum powder, and glass microspheres according to different applications. The material obtained after hot-pressing and sintering exhibits uniform composition and excellent performance.

[0005] The technical solution adopted in this invention is as follows: A method for preparing a carbon fiber reinforced aluminum / glass microsphere composite metal material, the method comprising the following steps: (1) Preparation of aluminum / glass microsphere powder suspension Aluminum powder and glass microsphere powder are mixed to obtain a mixture, and then anhydrous ethanol is added and stirred. After stirring for 1-2 hours, an aluminum / glass microsphere powder suspension is obtained. The volume of glass microsphere powder is 30%-70% of the volume of the mixture; the volume of anhydrous ethanol is 0.5-1 times the volume of the mixture. The aluminum powder has a particle size range of 1-150 μm, and the glass microspheres have a particle size range of 20-100 μm. (2) Preparation of nickel-plated carbon fiber / aluminum / glass microsphere powder suspension Nickel-plated carbon fiber was added to an aluminum / glass microsphere powder suspension under stirring. After stirring for 10-15 minutes, a nickel-plated carbon fiber / aluminum / glass microsphere powder suspension was obtained. Among them, nickel-plated carbon fiber accounts for 0.1%-1% of the total volume of aluminum powder and glass microsphere powder; The nickel-plated carbon fiber monofilament has a diameter of 5~10μm and a nickel layer thickness of 180-220nm; The stirring is a Z-axis reciprocating stirring, with a stirring speed of 200-300 rpm and a vertical reciprocating moving speed of 3-7 mm / s; (3) Drying of nickel-plated carbon fiber / aluminum / glass microsphere powder suspension The anhydrous ethanol in the suspension of nickel-plated carbon fiber / aluminum / glass microsphere powder was filtered by vacuum filtration, and then dried at 100-120℃ for 2-4 hours to obtain dried nickel-plated carbon fiber / aluminum / glass microsphere powder. (4) Preparation of carbon fiber reinforced aluminum / glass microsphere composite metal materials The dried nickel-plated carbon fiber / aluminum / glass microsphere powder obtained in the previous step was loaded into a graphite mold lined with graphite paper, and then carbon fiber reinforced aluminum / glass microsphere composite metal material was obtained by hot pressing sintering process. The hot-pressing sintering temperature is 580-620℃, the hot-pressing sintering pressure is 5-25MPa, the holding time is 1-2h, the heating rate is 10-15℃ / min, and the vacuum degree is 5×10⁻⁶. -2 Below Pa.

[0006] The essential features of this invention are: Current composite metal materials generally employ a process route of direct mixing of dry powders followed by sintering. However, aluminum matrix composites reinforced with single glass hollow microspheres have limitations. Simply increasing the wall thickness or reducing the particle size to improve the strength of the composite material will lead to a decrease in porosity and an increase in density. This invention adds nickel-plated carbon fibers to an aluminum / glass microsphere powder suspension under stirring. The reciprocating motion of the stirring along the Z-axis effectively prevents the carbon fibers from agglomerating. Then, through hot pressing and sintering in a graphite mold, the nickel and aluminum in the nickel-plated carbon fibers tend to form a continuous and uniform Al3Ni thin film at the interface, thereby hindering the formation of the brittle Al4C3 phase and realizing the transition of load from the matrix to the carbon fibers. The high specific modulus and high specific strength of the carbon fibers construct a three-dimensional microscopic load-bearing skeleton in the matrix. Under compressive load, the carbon fibers preferentially bear and transmit the main stress, effectively alleviating the stress concentration on the surface of the brittle glass microspheres, thereby delaying the premature crushing and breakage of the microspheres and significantly improving the peak strength of the material.

[0007] The beneficial effects of this invention are as follows: This invention successfully prepares carbon fiber reinforced aluminum-based composite foam by incorporating nickel-plated carbon fibers. During the hot-pressing sintering process, the nickel plating interdiffusions with the aluminum matrix to form intermetallic compounds, significantly improving the wettability between the carbon fibers and the aluminum matrix. Simultaneously, by controlling the hot-pressing sintering temperature and pressure, the integrity of the glass microspheres and carbon fibers is well preserved during the preparation process. By adjusting the amount of carbon fibers added, the energy absorption capacity is significantly improved compared to aluminum-based composite foam without carbon fibers, while avoiding carbon fiber agglomeration. The prepared composite material achieves a peak stress of up to 124.8 MPa, a plateau stress of up to 114.6 MPa, and an energy absorption capacity of up to 56 MJ / cm². 3 It has an energy absorption capacity of up to 51 J / g, which is about 107% higher than that of aluminum-based composite foam without added nickel-plated carbon fiber, and its mechanical properties are significantly improved.

[0008] The preparation method of this invention is low in cost, simple in process, easy to operate, and suitable for the preparation of large batches of composite materials. Furthermore, the Z-axis reciprocating stirring device can effectively avoid the agglomeration of carbon fibers through multi-level stirring. The nickel coating on the carbon fibers significantly improves the wettability between the carbon fibers and the aluminum matrix, providing the prerequisite for the preparation of large-volume samples, thus making it easy to realize industrial production and application. Attached Figure Description

[0009] Figure 1 These are SEM images of the raw material, nickel-plated carbon fiber. Figure 1 (a) shows the cross-section of nickel-plated carbon fiber. Figure 1 (b) shows the surface of nickel-plated carbon fiber; Figure 2 These are SEM images of the hot-pressed sintered carbon fiber reinforced aluminum / glass microsphere composite metal materials obtained in Examples 1-3; wherein, Figure 2 (a) is a photograph of the material obtained in Example 1. Figure 2 (b) is a photograph of the material obtained in Example 2. Figure 2 (c) A photograph of the material obtained in Example 3; Figure 3 These are photographs showing the distribution of the aluminum matrix, glass microspheres, and carbon fibers obtained in Example 2.

[0010] Figure 4 These are the stress-strain curves of ordinary aluminum / glass microsphere composite metal material and the composite material obtained in Examples 1-3.

[0011] Figure 5 It is a Z-axis reciprocating stirring device used in ordinary aluminum / glass microsphere composite metal materials and in Examples 1-3. Figure 6 This is an EPMA photograph of the interface between aluminum, glass microspheres, and nickel-plated carbon fiber in the composite material obtained in Example 1.

[0012] Figure 7 This is a photograph showing a large number of broken microspheres inside the composite material obtained in Comparative Example 1.

[0013] Figure 8 The image shows the composite material obtained in Comparative Example 2, which has many voids inside and exhibits microbead debonding.

[0014] Figure 9 This is a photograph of the uneven distribution of components in Comparative Example 3 due to insufficient stirring.

[0015] Figure 10 These are the stress-strain curves of ordinary aluminum / glass microsphere composite metal material and the composite material of Comparative Examples 4-6 after applying excess carbon fiber.

[0016] Figure 11These are the stress-strain curves of the composite materials obtained in Examples 2, 4, and 5. Detailed Implementation

[0017] The present invention will be further described below with reference to embodiments.

[0018] The nickel-plated carbon fiber of the present invention is a known material. The following examples use SYT49S nickel-plated carbon fiber from Shenzhen Xintai New Materials Co., Ltd. The nickel-plated carbon fiber has a single filament diameter of 7 μm, a nickel layer thickness of 180-220 nm, and a length of 3 mm. Figure 1 As shown; but not limited to.

[0019] The Z-axis reciprocating stirring device involved in this invention is a known device, and its structure is as follows: Figure 5 As shown in the diagram. This device ensures horizontal stirring while the stirring paddle can also move up and down at a set speed and stroke. However, it is not limited to this.

[0020] Example 1: Glass microspheres with a particle size of 50 μm and aluminum powder with a particle size of 1-2 μm were mixed and then anhydrous ethanol was added and stirred to obtain a mixed powder (V). 玻璃微珠体积 :V 铝粉 V 无水乙醇 The mixture was prepared using a Z-axis reciprocating stirring device at a speed of 250 rpm and a reciprocating speed of 5 mm / s to form a paste. Then, nickel-plated carbon fiber was added to the stirred aluminum / glass microsphere powder suspension, with the amount of carbon fiber added being 0.1% of the total volume of the aluminum powder and glass microspheres. After stirring for another 10 minutes, a uniformly mixed nickel-plated carbon fiber / aluminum / glass microsphere powder suspension was obtained. Excess anhydrous ethanol was filtered out from the above suspension. In order to obtain drier nickel-plated carbon fiber / aluminum / glass microsphere powder, the undried aluminum / glass microsphere powder was placed in a vacuum drying oven at 110°C for 2 hours to dry it, and finally the dried nickel-plated carbon fiber / aluminum / glass microsphere powder was obtained. Weigh out a certain amount of dry nickel-plated carbon fiber / aluminum / glass microsphere powder, and before pouring it into the graphite mold, fill the inside of the mold with 0.1mm thick graphite paper. Then pour the dry nickel-plated carbon fiber / aluminum / glass microsphere powder into it, and finally install the mold. The graphite mold was placed in a hot-press sintering furnace under a vacuum of 4×10⁻⁶. -2 The temperature was increased to 600℃ at a heating rate of 10℃ / min under Pa, and then the pressure was set to 15MPa and held at that temperature and pressure for 1 hour; finally, a composite material with a height of 35mm was obtained. A small piece was taken to observe its microstructure. Figure 2(a) It can be observed that aluminum powder and carbon fiber are well and uniformly distributed around the glass microspheres. The interfacial reaction between nickel-plated carbon fiber, glass microspheres, and aluminum matrix is ​​as follows: Figure 6 As shown, a thin film of intermetallic compound can be observed at the interface between the nickel-plated carbon fiber and the aluminum substrate, while there is no obvious interfacial reaction between the glass microspheres and the nickel-plated carbon fiber and the aluminum substrate. Using wire cutting technology, the obtained carbon fiber reinforced aluminum / glass microspheres were cut into cylinders with a diameter of 10 mm and a thickness of 10 mm. The surface of the cylinders was then polished and cleaned to ensure a smooth surface. The obtained cylindrical specimen was subjected to a compression test using an electronic universal testing machine with a strain rate of 10. -3 s -1 From the stress-strain curve Figure 4 The peak stress can reach 110 MPa.

[0021] Comparative Example 1: The other steps are the same as in Example 1, except that the hot-pressing sintering temperature is 630℃. In this case, the sample was difficult to demold, and due to the high preparation temperature, the aluminum powder was in a molten state. The pressure acting on the microspheres caused a large number of microspheres to break, and the carbon fibers to fracture, resulting in failure. Figure 7 As shown; Comparative Example 2: The other steps are the same as in Example 1, except that the hot-pressing sintering temperature is 550℃. The sample exhibits poor bonding, with numerous voids inside, causing microspheres to detach, resulting in insufficient strength and failure. Figure 8 As shown; Comparative Example 3: The other steps are the same as in Example 1, except that the stirring time after adding the nickel-plated carbon fiber is 5 minutes, and the components are not uniformly dispersed. Figure 9 As shown.

[0022] Comparative Examples 4-6: The other steps are the same as in Example 1, except that the amount of carbon fiber added is 1.1, 1.3, and 1.5 vol.% of the total volume of aluminum powder and glass microspheres, respectively. Excessive addition will cause the carbon fiber to agglomerate within the composite material, thereby reducing the peak stress and plateau stress. Figure 10 As shown, the peak stress of the sample without added carbon fiber was 79.6 MPa and the plateau stress was 72.3 MPa. The peak stresses of the samples with added carbon fiber content of 1.1%, 1.3%, and 1.5 vol.% were 77.5 MPa, 66.3 MPa, and 63.6 MPa, respectively, and the plateau stresses were 70 MPa, 59.5 MPa, and 50 MPa, respectively.

[0023] Comparative studies revealed that at around 550℃, the components of the composite material were not tightly bonded, resulting in numerous voids within the composite. The microspheres were not firmly bonded to the matrix, leading to a decrease in energy absorption. (The failure at 500℃ is not directly related to the formation of Al4C3; the bonding is not dense at 500℃, while Al4C3 is formed around 500℃. Even if the preparation temperature is 600℃, Al4C3 will still form around 500℃.) At around 630℃, the aluminum powder is close to a molten state. Under pressure, the molten aluminum is extruded from the mold, making demolding difficult. Furthermore, during the preparation process, the pressure head directly acts on the microspheres and carbon fibers, causing a large number of microspheres to break and carbon fibers to fracture, reducing the energy absorption capacity and leading to experimental failure. This invention, however, selects the 580-620℃ range for 3Al + Al3Ni is chemically stable and typically has higher fracture toughness than Al4C3. It also tends to form a continuous and uniform thin film-like interface layer at the interface, thereby hindering the formation of the brittle phase of Al4C3 and enabling the transition of load from the matrix to the carbon fiber.

[0024] Excessive sintering temperature and pressure will cause microspheres and carbon fibers to break or fracture prematurely during the preparation process, making it difficult for them to perform as intended in the test. Conversely, excessively low sintering temperature or pressure will weaken the bonding force between microspheres and carbon fibers and the aluminum matrix, and the presence of a large number of voids in the aluminum matrix will reduce the plateau strength and peak strength of the composite material.

[0025] Example 2: Glass microspheres with a particle size of 50 μm and aluminum powder with a particle size of 1-2 μm were mixed and then anhydrous ethanol was added and stirred to obtain a mixed powder (V). 玻璃微珠体积 :V 铝粉 V 无水乙醇 The mixture was prepared using a Z-axis reciprocating stirring device at a speed of 250 rpm and a reciprocating speed of 5 mm / s to form a paste. Then, nickel-plated carbon fiber was added to the stirred aluminum / glass microsphere powder suspension, with the amount of carbon fiber added being 0.3% of the total volume of the aluminum powder and glass microspheres. After stirring for another 10 minutes, a uniformly mixed nickel-plated carbon fiber / aluminum / glass microsphere powder suspension was obtained. Excess anhydrous ethanol was filtered out from the above suspension. In order to obtain drier nickel-plated carbon fiber / aluminum / glass microsphere powder, the undried aluminum / glass microsphere powder was placed in a vacuum drying oven at 110°C for 2 hours to dry it, and finally the dried nickel-plated carbon fiber / aluminum / glass microsphere powder was obtained. Weigh out a certain amount of dry nickel-plated carbon fiber / aluminum / glass microsphere powder, and before pouring it into the graphite mold, fill the inside of the mold with 0.1mm thick graphite paper. Then pour the dry nickel-plated carbon fiber / aluminum / glass microsphere powder into it, and finally install the mold. The graphite mold was placed in a hot-press sintering furnace under a vacuum of 4×10⁻⁶. -2 The temperature was increased to 600℃ at a heating rate of 10℃ / min under Pa, and then the pressure was set to 15MPa and held at that temperature and pressure for 1 hour; finally, a composite material with a height of 35mm was obtained. A small piece was taken to observe its microstructure. Figure 2 (b) The number of carbon fibers near the glass microspheres increases and the carbon fibers can be evenly distributed around the glass microspheres; hot pressing sintering technology can achieve the densification of composite materials at a lower temperature and can also avoid the reaction between carbon fibers, aluminum and microspheres.

[0026] Using wire cutting technology, the obtained carbon fiber reinforced aluminum / glass microspheres were cut into cylinders with a diameter of 10 mm and a thickness of 10 mm. The surface of the cylinders was then polished and cleaned to ensure a smooth surface. The obtained cylindrical specimen was subjected to a compression test using an electronic universal testing machine with a strain rate of 10. -3 s -1 From the stress-strain curve Figure 4 The peak stress can reach 125 MPa.

[0027] Example 3: Glass microspheres with a particle size of 50 μm and aluminum powder with a particle size of 1-2 μm were mixed and then anhydrous ethanol was added and stirred to obtain a mixed powder (V). 玻璃微珠体积 :V 铝粉 V 无水乙醇 The mixture was prepared using a Z-axis reciprocating stirring device at a speed of 250 rpm and a reciprocating speed of 5 mm / s to form a paste. Then, nickel-plated carbon fiber was added to the stirred aluminum / glass microsphere powder suspension, with the amount of carbon fiber added being 0.5% of the total volume of the aluminum powder and glass microspheres. After stirring for another 10 minutes, a uniformly mixed nickel-plated carbon fiber / aluminum / glass microsphere powder suspension was obtained. Excess anhydrous ethanol was filtered out from the above suspension. In order to obtain drier nickel-plated carbon fiber / aluminum / glass microsphere powder, the undried aluminum / glass microsphere powder was placed in a vacuum drying oven at 110°C for 2 hours to dry it, and finally the dried nickel-plated carbon fiber / aluminum / glass microsphere powder was obtained. Weigh out a certain amount of dry nickel-plated carbon fiber / aluminum / glass microsphere powder, and before pouring it into the graphite mold, fill the inside of the mold with 0.1mm thick graphite paper. Then pour the dry nickel-plated carbon fiber / aluminum / glass microsphere powder into it, and finally install the mold. The graphite mold was placed in a hot-press sintering furnace under a vacuum of 4×10⁻⁶. -2The temperature was increased to 600℃ at a heating rate of 10℃ / min under Pa, and then the pressure was set to 15MPa and held at that temperature and pressure for 1 hour; finally, a composite material with a height of 35mm was obtained. A small piece was taken to observe its microstructure. Figure 2 (c) It can be observed that the high carbon fiber content leads to partial agglomeration; Using wire cutting technology, the obtained carbon fiber reinforced aluminum / glass microspheres were cut into cylinders with a diameter of 10 mm and a thickness of 10 mm. The surface of the cylinders was then polished and cleaned to ensure a smooth surface. The obtained cylindrical specimen was subjected to a compression test using an electronic universal testing machine with a strain rate of 10. -3 s -1 From the stress-strain curve Figure 4 The peak stress can reach 98 MPa. Although there is local carbon fiber agglomeration at 0.5 vol.%, the overall reinforcing network formed by this and the interface formed by the nickel plating layer effectively transfer the load, which is sufficient to compensate for the negative impact of stress concentration caused by carbon fiber agglomeration, so that the material macroscopically exhibits better performance than the sample without added fibers.

[0028] Example 4: 1. Glass microsphere powder with a particle size of 50 μm and aluminum powder with a particle size of 1-2 μm are mixed, and then anhydrous ethanol is added and stirred to obtain a mixed powder (V). 玻璃微珠体积 :V 铝粉 V 无水乙醇 The mixture was prepared using a Z-axis reciprocating stirring device at a speed of 250 rpm and a reciprocating speed of 5 mm / s to form a paste. Then, nickel-plated carbon fiber was added to the stirred aluminum / glass microsphere powder suspension, with the amount of carbon fiber added being 0.3% of the total volume of the aluminum powder and glass microspheres. After stirring for another 10 minutes, a uniformly mixed nickel-plated carbon fiber / aluminum / glass microsphere powder suspension was obtained. 2. The excess anhydrous ethanol in the above suspension was filtered out. In order to obtain drier nickel-plated carbon fiber / aluminum / glass microsphere powder, the undried aluminum / glass microsphere powder was placed in a vacuum drying oven and dried at 110°C for 2 hours to finally obtain dry nickel-plated carbon fiber / aluminum / glass microsphere powder. 3. Weigh a certain amount of dry nickel-plated carbon fiber / aluminum / glass microsphere powder. Before pouring it into the graphite mold, fill the inside of the mold with 0.1mm thick graphite paper. Then pour the dry nickel-plated carbon fiber / aluminum / glass microsphere powder into it and finally install the mold. 4. Place the graphite mold into a hot-press sintering furnace, under a vacuum of 4×10⁻⁶. -2 The temperature was increased to 580℃ at a heating rate of 10℃ / min under Pa, and then the pressure was set to 15MPa and held for 1 hour; finally, a composite material with a height of 35mm was obtained.

[0029] 5. Using wire cutting technology, the obtained carbon fiber reinforced aluminum / glass microspheres are cut into cylinders with a diameter of 10mm and a thickness of 10mm. The surface of the cylinders is polished and cleaned to ensure a smooth surface. 6. The obtained cylindrical specimen was subjected to a compression test using an electronic universal testing machine with a strain rate of 10. -3 s -1 From the stress-strain curve Figure 11 The peak stress can reach 85 MPa. Due to the low sintering temperature, the overall densification of the material is insufficient, and the poor interfacial bonding leads to limited load transfer. Therefore, the performance is worse than that of samples sintered at higher temperatures.

[0030] Example 5: 1. Glass microsphere powder with a particle size of 50 μm and aluminum powder with a particle size of 1-2 μm are mixed, and then anhydrous ethanol is added and stirred to obtain a mixed powder (V). 玻璃微珠体积 :V 铝粉 V 无水乙醇 The mixture was prepared using a Z-axis reciprocating stirring device at a speed of 250 rpm and a reciprocating speed of 5 mm / s to form a paste. Then, nickel-plated carbon fiber was added to the stirred aluminum / glass microsphere powder suspension, with the amount of carbon fiber added being 0.3% of the total volume of the aluminum powder and glass microspheres. After stirring for another 10 minutes, a uniformly mixed nickel-plated carbon fiber / aluminum / glass microsphere powder suspension was obtained. 2. The excess anhydrous ethanol in the above suspension was filtered out. In order to obtain drier nickel-plated carbon fiber / aluminum / glass microsphere powder, the undried aluminum / glass microsphere powder was placed in a vacuum drying oven and dried at 110°C for 2 hours to finally obtain dry nickel-plated carbon fiber / aluminum / glass microsphere powder. 3. Weigh a certain amount of dry nickel-plated carbon fiber / aluminum / glass microsphere powder. Before pouring it into the graphite mold, fill the inside of the mold with 0.1mm thick graphite paper. Then pour the dry nickel-plated carbon fiber / aluminum / glass microsphere powder into it and finally install the mold. 4. Place the graphite mold into a hot-press sintering furnace, under a vacuum of 4×10⁻⁶. -2 The temperature was increased to 620℃ at a heating rate of 10℃ / min under Pa, and then the pressure was set to 15MPa and held for 1 hour; finally, a composite material with a height of 35mm was obtained.

[0031] 5. Using wire cutting technology, the obtained carbon fiber reinforced aluminum / glass microspheres are cut into cylinders with a diameter of 10mm and a thickness of 10mm. The surface of the cylinders is polished and cleaned to ensure a smooth surface. 6. The obtained cylindrical specimen was subjected to a compression test using an electronic universal testing machine with a strain rate of 10. -3 s -1 From the stress-strain curve Figure 11 The peak stress can reach 128 MPa.

[0032] As can be seen from the above examples and comparative examples, mixing dry materials together results in uneven mixing, leading to poor performance after direct melting. Adding a large amount of anhydrous ethanol, which mixes the powder into a paste-like consistency, increases the wettability (viscosity) of the glass microspheres, allowing for better and more uniform mixing of the aluminum powder and glass microsphere powder. The anhydrous ethanol acts as a bridge between the aluminum powder and the glass microspheres. During melting, a sintering temperature below the melting point of aluminum was used, melting before the aluminum powder was completely melted. This prevented the glass microspheres from floating due to their low density, thus avoiding uneven dispersion (glass microsphere density (0.44 g / cm³)). 3 If the melting temperature is too high, aluminum will float because its density is too low. Therefore, the melting temperature should be below the melting point of aluminum (660°C).

[0033] Meanwhile, the amount of nickel-plated carbon fiber added should be strictly controlled. When the addition ratio is too high, the carbon fiber will agglomerate inside the composite material, resulting in stress concentration. During the test, it will become a crack source and cause the material to break prematurely. When the addition ratio is too low, the carbon fiber will be difficult to form an effective reinforcing network, making it difficult to delay the crack propagation and thus having a weak effect on improving energy absorption capacity.

[0034] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

[0035] Matters not covered in this invention are common knowledge.

Claims

1. A method for preparing a carbon fiber reinforced aluminum / glass microsphere composite metal material, characterized in that, The method includes the following steps: (1) Preparation of aluminum / glass microsphere powder suspension Aluminum powder and glass microsphere powder are mixed to obtain a mixture, and then anhydrous ethanol is added and stirred. After stirring for 1-2 hours, an aluminum / glass microsphere powder suspension is obtained. The volume of glass microsphere powder is 30%-70% of the volume of the mixture; the volume of anhydrous ethanol is 0.5-1 times the volume of the mixture. (2) Preparation of nickel-plated carbon fiber / aluminum / glass microsphere powder suspension Nickel-plated carbon fiber was added to an aluminum / glass microsphere powder suspension under stirring. After stirring for 10-15 minutes, a nickel-plated carbon fiber / aluminum / glass microsphere powder suspension was obtained. Among them, nickel-plated carbon fiber accounts for 0.1%-1% of the total volume of aluminum powder and glass microsphere powder; (3) Drying of nickel-plated carbon fiber / aluminum / glass microsphere powder suspension The anhydrous ethanol in the suspension of nickel-plated carbon fiber / aluminum / glass microsphere powder was filtered by vacuum filtration, and then dried at 100-120℃ for 2-4 hours to obtain dried nickel-plated carbon fiber / aluminum / glass microsphere powder. (4) Preparation of carbon fiber reinforced aluminum / glass microsphere composite metal materials The dried nickel-plated carbon fiber / aluminum / glass microsphere powder obtained in the previous step is loaded into a graphite mold lined with graphite paper, and then carbon fiber reinforced aluminum / glass microsphere composite metal material is obtained by hot pressing sintering process.

2. The method for preparing the carbon fiber reinforced aluminum / glass microsphere composite metal material as described in claim 1, characterized in that, The aluminum powder has a particle size range of 1-150 μm, and the glass microspheres have a particle size range of 20-100 μm.

3. The method for preparing the carbon fiber reinforced aluminum / glass microsphere composite metal material as described in claim 1, characterized in that, The nickel-plated carbon fiber monofilament has a diameter of 5~10μm and a nickel layer thickness of 180-220nm.

4. The method for preparing the carbon fiber reinforced aluminum / glass microsphere composite metal material as described in claim 1, characterized in that, The stirring is a Z-axis reciprocating stirring with a stirring speed of 200-300 rpm and an up-and-down reciprocating moving speed of 3-7 mm / s.

5. The method for preparing the carbon fiber reinforced aluminum / glass microsphere composite metal material as described in claim 1, characterized in that, In step (4), the parameters for the hot pressing sintering process are: temperature 580-620℃, hot pressing sintering pressure 5-25MPa, holding time 1-2h, heating rate 10-15℃ / min, and vacuum degree 5×10 -2 Below Pa.

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