Reinforced aluminum-based material and preparation method thereof

Abstract

The invention relates to the technical field of aluminum alloy additive manufacturing, in particular to a reinforced aluminum-based material and a preparation method thereof.The preparation method comprises the following steps that nano metal powder and micron non-metal ceramic powder are added into a mixing tank, a protective atmosphere is formed in the mixing tank, the gas pressure in the tank and the tank temperature are set, and the temperature of the tank is set; a three-section acoustic resonance method is adopted for coating and powder preparation, nano metal powder is used for coating micron nonmetal ceramic powder, and the composite powder material with a core-shell structure is prepared. In the three-section acoustic resonance method, the resonance frequency of the first section is 20 Hz-50 Hz, the mixing acceleration is 10 g-100 g, and the mixing time is 1 min-5 min; in the second stage, the resonant frequency is 60 Hz-100 Hz, the mixing acceleration is 110 g-200 g, and the mixing time is 3 min-20 min; and in the third stage, the resonant frequency is 40-70 Hz, the mixing acceleration is 80-130 g, and the mixing time is 1-10 min.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy additive manufacturing technology, specifically to a reinforced aluminum-based material and its preparation method. Background Technology

[0002] Aluminum alloys, with their low density, high specific strength, good corrosion resistance, and excellent thermal conductivity, have become important lightweight alloy powder materials in the field of metal additive manufacturing. Metal 3D printing technology achieves the structural forming of complex components by depositing metal powder layer by layer, and has broad application prospects in aerospace, automotive manufacturing, and other fields.

[0003] However, ceramic-reinforced aluminum alloys prepared by existing technologies have significant drawbacks: insufficient fracture toughness, making them prone to brittle fracture under dynamic loads; poor stability at high temperatures, with heat resistance failing to meet engineering requirements; and low interfacial bonding strength between the ceramic reinforcement phase and the aluminum matrix, resulting in poor wettability and stress concentration areas at the interface. Upon impact, these areas are highly susceptible to crack initiation and propagation along the interface, severely weakening the overall mechanical properties of the material. These problems severely restrict the application of ceramic-reinforced aluminum alloys in high-performance structural components, necessitating the development of novel preparation processes to improve interfacial bonding and enhance the overall material performance. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a reinforced aluminum-based material and its preparation method, which solves the technical problem that the poor interfacial bonding quality of the reinforced aluminum-based material prepared by the existing process leads to poor overall mechanical properties of the material.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a method for preparing reinforced aluminum-based materials, comprising the following steps: Nano-metal powder, first-micron non-metallic ceramic powder, and second-micron non-metallic ceramic powder are added to a mixing tank. A protective atmosphere is formed inside the mixing tank. The gas pressure and temperature inside the tank are set. A three-stage acoustic resonance method is used for coating powder preparation. The nano-metal powder coats the first-micron non-metallic ceramic powder to form a first composite powder material. The nano-metal powder coats the second-micron non-metallic ceramic powder to form a second composite powder material. The first composite powder material and the second composite powder material with core-shell structure are obtained. Aluminum alloy, first composite powder material and second composite powder material are added to a mixing tank to form a protective atmosphere in the mixing tank. The gas pressure and temperature inside the tank are set, and the mixture is uniformly mixed using an acoustic resonance method with a resonance frequency of 30Hz to 50Hz, a mixing acceleration of 10g to 100g and a mixing time of 1min to 10min to obtain a mixed powder material. Reinforced aluminum-based materials were prepared using laser metal 3D printing technology with mixed powder materials as raw materials. In the three-segment acoustic resonance method, 1g = 9.8m / s² 2 The first segment has a resonant frequency of 30Hz to 50Hz, a mixing acceleration of 10g to 100g, and a mixing time of 1min to 10min; the second segment has a resonant frequency of 60Hz to 100Hz, a mixing acceleration of 110g to 200g, and a mixing time of 3min to 20min; the third segment has a resonant frequency of 50Hz to 70Hz, a mixing acceleration of 80g to 130g, and a mixing time of 1min to 10min. The purity of the nano-metal powder is greater than 99.9%, and the total amount of the first composite powder material and the second composite powder material is added at a ratio of 2% to 5% by mass of the mixed powder material.

[0006] In one possible implementation, the laser metal 3D printing technology features a power of 370W–390W, a printing speed of 1100mm / s–1500mm / s, a line spacing of 0.15mm–0.19mm, a printing thickness of 0.03mm, and an energy density of 43J / mm². 3 ~65J / mm 3 .

[0007] In one possible implementation, the average particle size of the nano-metal powder is 50 nm to 100 nm, and the average particle size of the micron-sized non-metallic ceramic powder is 50 μm to 500 μm.

[0008] In one possible implementation, the sum of the first micrometer non-metallic ceramic powder and the second micrometer non-metallic ceramic powder is referred to as micrometer non-metallic ceramic powder, and the mass ratio of the nano-metallic powder to the micrometer non-metallic ceramic powder is 1 to 2.

[0009] In one possible implementation, the nano-metal powder is Ni powder, and the first micron non-metallic ceramic powder or the second micron non-metallic ceramic powder is one of TiC powder and TiB2 powder.

[0010] In one possible implementation, the protective gas is nitrogen or an inert gas.

[0011] In one possible implementation, the volume ratio of the nano-metal powder to the micron-sized non-metallic ceramic powder in the mixing tank is 50% to 80%.

[0012] In one possible implementation, the absolute pressure inside the mixing tank is 50 kPa to 10 MPa, and the temperature of the tank body inside the mixing tank is... 10℃~100℃.

[0013] In one possible implementation, the mixing tank is made of stainless steel.

[0014] The present invention also provides a reinforced aluminum-based material, which is prepared by the above-described method for preparing reinforced aluminum-based materials.

[0015] The beneficial effects of this invention are that, compared with the prior art, this invention achieves uniform coating of nano-metal powder onto micron-sized non-metallic ceramic powder to form a core-shell structure through a three-segment acoustic resonance method, and optimizes mixing and printing parameters, effectively solving the problem of low interfacial bonding strength between the ceramic reinforcing phase and the aluminum matrix. It has the advantages of effectively improving the interfacial bonding state, improving the fracture toughness and high-temperature stability of the material, and enhancing the overall mechanical properties. It solves the technical problem that the poor interfacial bonding quality of the reinforced aluminum-based materials prepared by the existing process leads to poor overall mechanical properties of the material. Attached Figure Description

[0016] Figure 1 This is a SEM image of the mixture of the first composite powder material and the second composite powder material prepared in Example 1 of the present invention.

[0017] Figure 2 This is a photograph of the reinforced aluminum-based material prepared in Example 1 of the present invention.

[0018] Figure 3 A photograph of a cylindrical sample of the reinforced aluminum-based material provided by this invention.

[0019] Figure 4 A statistical chart showing the mechanical property test results of the cylindrical specimen provided by this invention. Detailed Implementation

[0020] To address the aforementioned technical problems, this invention provides an enhanced aluminum-based material and its preparation method. The technical solution and embodiments of this invention will now be described in detail with reference to the accompanying drawings.

[0021] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0022] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation", "connection" and "joining" should be interpreted broadly, for example, they can refer to fixed connection, detachable connection, or integral connection; for those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0023] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0024] In the field of metal additive manufacturing, the interfacial bonding quality between ceramic particles and the aluminum matrix is ​​often insufficient during the preparation of ceramic particle-reinforced aluminum alloys. Due to poor wettability, microcracks and stress concentration areas easily form at the interface, leading to reduced fracture performance, as well as insufficient heat resistance and impact resistance. Furthermore, the presence of interfacial defects makes the material prone to premature failure under external loads, affecting the overall structural integrity. If the interfacial bonding problem is not resolved, the reliability of materials in critical applications cannot be guaranteed. Interfacial defects accelerate the fracture process, making the material unable to withstand expected operating conditions, thus limiting its applicability in high-temperature or dynamic load environments. Therefore, improving the quality of interfacial bonding is a necessary condition for improving the overall performance of materials.

[0025] This invention provides a method for preparing a reinforced aluminum-based material, comprising the following steps: Nano-metal powder, first-micron non-metallic ceramic powder, and second-micron non-metallic ceramic powder are added to a mixing tank. A protective atmosphere is formed inside the mixing tank. The gas pressure and temperature inside the tank are set. A three-stage acoustic resonance method is used for coating powder preparation. The nano-metal powder coats the first-micron non-metallic ceramic powder to form a first composite powder material. The nano-metal powder coats the second-micron non-metallic ceramic powder to form a second composite powder material. The first composite powder material and the second composite powder material with core-shell structure are obtained. Aluminum alloy, first composite powder material and second composite powder material are added to a mixing tank to form a protective atmosphere in the mixing tank. The gas pressure and temperature inside the tank are set, and the mixture is uniformly mixed using an acoustic resonance method with a resonance frequency of 30Hz to 50Hz, a mixing acceleration of 10g to 100g and a mixing time of 1min to 10min to obtain a mixed powder material. Reinforced aluminum-based materials were prepared using laser metal 3D printing technology with mixed powder materials as raw materials. In the three-segment acoustic resonance method, 1g = 9.8m / s² 2 The first segment has a resonant frequency of 30Hz to 50Hz, a mixing acceleration of 10g to 100g, and a mixing time of 1min to 10min; the second segment has a resonant frequency of 60Hz to 100Hz, a mixing acceleration of 110g to 200g, and a mixing time of 3min to 20min; the third segment has a resonant frequency of 50Hz to 70Hz, a mixing acceleration of 80g to 130g, and a mixing time of 1min to 10min. The purity of the nano-metal powder is greater than 99.9%, and the mass percentage of aluminum alloy in the mixed powder material is 2% to 5%. In laser metal 3D printing technology, the power is 370W–390W, the printing speed is 1100 mm / s–1500 mm / s, the line spacing is 0.15mm–0.19mm, the printing thickness is 0.03mm, and the energy density is 43J / mm². 3 ~65 J / mm 3 .

[0026] Laser power refers to the energy intensity of the laser beam output, which can be achieved using a tunable fiber laser. The purpose is to avoid excessive power causing oxidation and decomposition of the nano-metal cladding layer or insufficient fusion due to excessive power.

[0027] Printing speed can be understood as the rate at which the laser beam moves across the material surface. It can be achieved using a high-precision servo motor-driven galvanometer scanning system. The purpose is to control the cooling rate of the molten pool to prevent incomplete fusion between layers or excessive heat accumulation.

[0028] Line spacing refers to the distance between adjacent scanning paths. It can be achieved by using a CNC system to precisely control the scanning path planning, with the aim of ensuring the overlap of scanning paths and eliminating unmelted areas.

[0029] Printing thickness refers to the deposition thickness of a single layer of material, which can be achieved through a precise adjustment mechanism of the powder spreading roller. The purpose is to control the precision of layer-by-layer forming and reduce residual stress.

[0030] Energy density refers to the energy received by a unit volume of material. It can be achieved through comprehensive control of power, speed, line spacing and layer thickness, with the aim of balancing heat input and material response characteristics.

[0031] The above process, through the design of the core-shell structure and the gradient control of acoustic resonance parameters, makes the nano-metal coating layer an effective transition layer between ceramic particles and aluminum matrix, significantly improving interfacial wettability and reducing stress concentration at the interface, thereby improving the fracture toughness and impact resistance of the material. At the same time, the segmented coating process ensures the enhancement of the surface activity of ceramic particles, avoiding the interfacial cracking problem caused by insufficient wettability in traditional methods, and finally obtaining a reinforced aluminum-based material with stable performance.

[0032] The present invention will now be described in detail through specific embodiments. These embodiments are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0033] In the following embodiments, unless otherwise specified, the methods described are conventional methods; and unless otherwise specified, the reagents and materials described are commercially available.

[0034] Example 1 The first micrometer of non-metallic ceramic powder is TiC ceramic powder, and the second micrometer of non-metallic ceramic powder is TiB2 ceramic powder, with an average particle size of 100 μm. The nano-metallic powder is nickel powder, with an average particle size of 50 nm.

[0035] This embodiment provides a method for preparing reinforced aluminum-based materials, including the following steps: Weigh 300g of TiC ceramic powder, 300g of TiB2 ceramic powder and 400g of nickel powder into a 150ml PC mixing tank according to a mass ratio of 3:3:4. Place the mixing tank on a Hummingbird HAM500 acoustic resonance mixer and evacuate it to an absolute pressure of about 1kPa. Fill the tank with inert nitrogen gas until the absolute pressure is 0.1MPa. The three-stage acoustic resonance coating process parameters were set as follows: the first stage resonant frequency was 30Hz, the mixing acceleration was 40g, and the mixing time was 3min; the second stage resonant frequency was 60Hz, the mixing acceleration was 110g, and the mixing time was 15min; the third stage resonant frequency was 40Hz, the mixing acceleration was 90g, and the mixing time was 5min, resulting in a first composite powder material of nickel-coated TiC with a core-shell structure and a second composite powder material of nickel-coated TiB2 powder. Aluminum alloy, first composite powder material, and second composite powder material are added to a mixing tank, a protective atmosphere is formed inside the mixing tank, and the gas pressure and temperature inside the tank are set. The mixture is homogenized using an acoustic resonance method with a resonance frequency of 30Hz, a mixing acceleration of 40g, and a mixing time of 10min to obtain a mixed powder material. The total amount of the first composite powder material and the second composite powder material added is 5% by mass of the mixed powder material. Reinforced aluminum-based materials were prepared using laser metal 3D printing technology based on mixed powder materials. A sample image is shown below. Figure 2 As shown.

[0036] The parameters for laser metal 3D printing technology are as follows: power 380W, printing speed 1100mm / s, line spacing 0.15mm, printing thickness 0.03mm, and energy density 43J / mm². 3 .

[0037] SEM testing: A Hitachi S-4800 field emission scanning electron microscope was used, and the testing conditions were an accelerating voltage of 5kV.

[0038] Figure 1 The image shows a SEM image of the mixture of the first composite powder material and the second composite powder material prepared in Example 1. It can be seen from the image that the nickel coating layer is uniformly and tightly adhered to the TiC particles and TiB2 particles.

[0039] Cylindrical specimens were prepared from the reinforced aluminum-based material prepared in Example 1 using wire cutting. The diameter and height of the cylindrical specimens were 4 mm. Figure 3 As shown.

[0040] The mechanical properties of the cylindrical specimens were tested using a testing machine. Four cylindrical specimens were taken for testing and labeled as 1#, 2#, 3#, and 4#. Figure 4 As shown in the figure, the mechanical properties of the reinforced aluminum-based material prepared in Example 1 are significantly improved.

[0041] The above description is merely a preferred embodiment of the present invention, and the specific embodiments described above are not intended to limit the present invention. Various modifications and variations can be made within the scope of the technical concept of the present invention. All refinements, modifications, or equivalent substitutions made by those skilled in the art based on the above description are within the scope of protection of the present invention.

Claims

1. A method for preparing reinforced aluminum-based materials, characterized in that, Includes the following steps: Nano-metal powder, first-micron non-metallic ceramic powder, and second-micron non-metallic ceramic powder are added to a mixing tank. A protective atmosphere is formed inside the mixing tank. The gas pressure and temperature inside the tank are set. A three-stage acoustic resonance method is used for coating powder preparation. The nano-metal powder coats the first-micron non-metallic ceramic powder to form a first composite powder material. The nano-metal powder coats the second-micron non-metallic ceramic powder to form a second composite powder material. The first composite powder material and the second composite powder material with core-shell structure are obtained. Aluminum alloy, first composite powder material and second composite powder material are added to a mixing tank, a protective atmosphere is formed in the mixing tank, the gas pressure and temperature in the tank are set, and the mixture is uniformly mixed by acoustic resonance method with a resonance frequency of 30Hz to 50Hz, a mixing acceleration of 10g to 100g and a mixing time of 1min to 10min to obtain a mixed powder material. Reinforced aluminum-based materials were prepared using laser metal 3D printing technology with mixed powder materials as raw materials. In the three-segment acoustic resonance method, 1g = 9.8m / s² 2 The first segment has a resonant frequency of 30Hz to 50Hz, a mixing acceleration of 10g to 100g, and a mixing time of 1min to 10min; the second segment has a resonant frequency of 60Hz to 100Hz, a mixing acceleration of 110g to 200g, and a mixing time of 3min to 20min; the third segment has a resonant frequency of 50Hz to 70Hz, a mixing acceleration of 80g to 130g, and a mixing time of 1min to 10min. The purity of the nano-metal powder is greater than 99.9%, and the total amount of the first composite powder material and the second composite powder material is added at a ratio of 2% to 5% by mass of the mixed powder material.

2. The preparation method according to claim 1, characterized in that, In the laser metal 3D printing technology described above, the power is 370W to 390W, the printing speed is 1100mm / s to 1500mm / s, the line spacing is 0.15mm to 0.19mm, the printing thickness is 0.03mm, and the energy density is 43J / mm². 3 ~65J / mm 3 .

3. The preparation method according to claim 1, characterized in that, The average particle size of the nano-metal powder is 50 nm to 100 nm, and the average particle size of the micron-sized non-metallic ceramic powder is 50 μm to 500 μm.

4. The preparation method according to claim 3, characterized in that, The sum of the first micrometer non-metallic ceramic powder and the second micrometer non-metallic ceramic powder is called micrometer non-metallic ceramic powder, and the mass ratio of the nano-metallic powder to the micrometer non-metallic ceramic powder is 1 to 2.

5. The preparation method according to any one of claims 1 to 4, characterized in that, The nano-metal powder is Ni powder, and the first micron non-metallic ceramic powder or the second micron non-metallic ceramic powder is one of TiC powder and TiB2 powder.

6. The preparation method according to claim 1, characterized in that, The protective gas is nitrogen or an inert gas.

7. The preparation method according to claim 5, characterized in that, The volume ratio of the nano-metal powder to the micron-sized non-metallic ceramic powder in the mixing tank is 50% to 80%.

8. The preparation method according to claim 1, characterized in that, The absolute pressure inside the mixing tank is 50 kPa to 10 MPa, and the temperature inside the mixing tank is... 10℃~100℃.

9. The preparation method according to claim 1, characterized in that, The mixing tank is made of stainless steel.

10. A reinforced aluminum-based material, characterized in that, The material is prepared by the method described in any one of claims 1 to 9.

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