Foamed aluminum damping material and preparation method thereof
By using a combination of dolomite foaming agent and modified boron carbide powder to prepare foamed aluminum shock-absorbing materials, the problem of balancing mechanical properties and shock-absorbing properties of foamed aluminum materials is solved, and higher porosity and mechanical properties are achieved.
Patent Information
- Application Number
- CN202511004052.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-21
- Publication Date
- 2025-10-21
AI Technical Summary
Existing foam aluminum materials have deficiencies in balancing mechanical properties and shock absorption performance, and it is difficult to improve both at the same time.
Dolomite foaming agent is used to replace the traditional calcium carbonate foaming agent, and modified boron carbide powder is added to the aluminum powder. The foamed aluminum shock-absorbing material is prepared through the steps of spray drying, ball milling, pressing and sintering.
The prepared foam aluminum shock-absorbing material has a finer and more uniform pore structure, which improves the energy absorption performance and mechanical properties.
Smart Images
Figure BDA0005510275300000061 
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of foam aluminum-based composite materials, and in particular to a foam aluminum shock-absorbing material and a preparation method thereof. Background Art
[0002] As an emerging functional structural material, aluminum foam boasts excellent thermodynamic, mechanical, and physical properties, and is characterized by lightness, heat insulation, sound insulation, energy resistance, high specific stiffness, high specific surface area, electromagnetic shielding, and corrosion resistance. Aluminum foam is a porous composite structural functional material based on metallic aluminum, characterized by high specific stiffness, high specific surface area, low density, light weight, and energy absorption. It is widely used in aerospace, automotive lightweighting, environmental protection, and construction industries. The high damping of aluminum foam is related to its porosity, pore size, and load-strain amplitude. The higher the porosity, the smaller the pore size, the larger the strain amplitude, and the higher the damping of the material. Aluminum foam is an excellent shock-absorbing material used in automobile bumpers and aircraft landing gear. Parts made of aluminum foam not only have good deformation capabilities but also reduce the overall weight of the vehicle body.
[0003] However, the mechanical properties of pure aluminum foam are poor. How to improve the mechanical properties of aluminum foam while also achieving good shock absorption is a difficult problem faced by this field. Therefore, it is of great significance to study a foam aluminum shock absorption material and its preparation method. Summary of the Invention
[0004] The object of the present invention is to provide a foam aluminum shock-absorbing material and a preparation method thereof, so as to solve the problem in the prior art that foam aluminum cannot take into account both mechanical properties and shock-absorbing properties.
[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:
[0006] The present invention provides a method for preparing a foam aluminum shock-absorbing material, comprising the following steps:
[0007] (1) Immersing boron carbide powder in aluminum sol and preparing modified boron carbide powder by spray drying;
[0008] (2) mixing the modified boron carbide powder and aluminum powder and then ball milling the mixture to obtain a mixed powder;
[0009] (3) The mixed powder, dolomite foaming agent and ethanol are mixed and then pressed and sintered in sequence to obtain foamed aluminum shock-absorbing material.
[0010] Preferably, in step (1), the mass ratio of the boron carbide powder to the aluminum sol is 0.5 to 0.8:1.
[0011] Preferably, in step (2), the mass ratio of the modified boron carbide powder to the aluminum powder is 5 to 15:100.
[0012] Preferably, in step (2), the rotation speed of the ball milling treatment is 300 to 500 rpm, and the time of the ball milling treatment is 4 to 6 hours.
[0013] Preferably, in step (3), the mass ratio of the mixed powder, dolomite foaming agent and ethanol is 100:0.5-3:10-20.
[0014] Preferably, in step (3), the pressing pressure is 200 to 600 MPa.
[0015] Preferably, in step (3), the sintering is carried out in steps, including a first sintering step and a second sintering step.
[0016] Preferably, the first sintering step has a heating rate of 1-5°C / min, a temperature of 300-400°C, and a sintering time of 1-3 hours.
[0017] Preferably, the heating rate of the second sintering step is 5-10°C / min, the temperature is 600-700°C, and the time is 0.5-1.5h.
[0018] The present invention also provides a foamed aluminum shock-absorbing material prepared by the above-mentioned method for preparing the foamed aluminum shock-absorbing material.
[0019] Beneficial effects of the present invention:
[0020] (1) The present invention uses dolomite foaming agent to replace the traditional calcium carbonate foaming agent, and the prepared foam aluminum shock-absorbing material has a finer and more evenly distributed pore structure, improves the porosity, and has higher energy absorption performance.
[0021] (2) Adding modified boron carbide powder to the aluminum powder raw material forms a reinforcing phase in the foam aluminum shock-absorbing material, thereby improving the mechanical properties of the foam aluminum shock-absorbing material. DETAILED DESCRIPTION
[0022] The present invention provides a method for preparing a foam aluminum shock-absorbing material, comprising the following steps:
[0023] (1) Immersing boron carbide powder in aluminum sol and preparing modified boron carbide powder by spray drying;
[0024] (2) mixing the modified boron carbide powder and aluminum powder and then ball milling the mixture to obtain a mixed powder;
[0025] (3) The mixed powder, dolomite foaming agent and ethanol are mixed and then pressed and sintered in sequence to obtain foamed aluminum shock-absorbing material.
[0026] In the present invention, the aluminum sol is preferably prepared by mixing aluminum alkoxide, alcohol and water and reacting them to prepare the aluminum sol.
[0027] In the present invention, the molar ratio of the aluminum alkoxide, alcohol and water is 1:23-45:55-100, preferably 1:28-40:70-90, and more preferably 1:32-35:80.
[0028] In the present invention, the reaction temperature is 70-80° C., preferably 72-78° C., more preferably 75° C., and the reaction time is 1-3 h, preferably 2 h.
[0029] In the present invention, in step (1), the mass ratio of the boron carbide powder to the aluminum sol is 0.5 to 0.8:1, preferably 0.6 to 0.7:1, and more preferably 0.65:1.
[0030] In the present invention, the inlet temperature during spray drying is 150-300°C, preferably 180-250°C, more preferably 200-220°C, and the outlet temperature is 70-140°C, preferably 80-120°C, more preferably 90-110°C.
[0031] In the present invention, in step (2), the mass ratio of the modified boron carbide powder to the aluminum powder is 5 to 15:100, preferably 8 to 12:100, and more preferably 10:100.
[0032] In the present invention, in step (2), the rotation speed of the ball milling treatment is 300-500 rpm, preferably 350-450 rpm, more preferably 400 rpm, and the ball milling treatment time is 4-6 h, preferably 4.5-5.5 h, more preferably 5 h.
[0033] In the present invention, in step (3), the mass ratio of the mixed powder, dolomite foaming agent and ethanol is 100:0.5-3:10-20, preferably 100:1.0-2.0:12-18, and more preferably 100:1.5:15.
[0034] In the present invention, in step (3), the pressure of the press molding is 200 to 600 MPa, preferably 250 to 550 MPa, more preferably 300 to 500 MPa, and even more preferably 400 MPa.
[0035] In the present invention, in step (3), the sintering is performed in steps, including a first sintering step and a second sintering step.
[0036] In the present invention, the heating rate of the first sintering step is 1-5°C / min, preferably 2-4°C / min, more preferably 3°C / min, the temperature is 300-400°C, preferably 320-380°C, more preferably 350°C, and the time is 1-3h, preferably 1.5-2.5h, more preferably 2h.
[0037] In the present invention, the heating rate of the second sintering step is 5-10°C / min, preferably 6-9°C / min, more preferably 7-8°C / min; the temperature is 600-700°C, preferably 620-680°C, more preferably 650°C; the time is 0.5-1.5h, preferably 1h.
[0038] The present invention also provides a foamed aluminum shock-absorbing material prepared by the above-mentioned method for preparing the foamed aluminum shock-absorbing material.
[0039] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.
[0040] Example 1
[0041] 1 mol of aluminum isopropoxide was dissolved in 32 mol of ethanol, and after stirring evenly, 80 mol of deionized water was added, and the mixture was placed in a homogenizer, heated to 75° C. for reaction, and after reacting for 2 hours, naturally cooled to room temperature to obtain aluminum sol.
[0042] Boron carbide powder (particle size 1-5 μm) and aluminum sol were mixed in a mass ratio of 0.65:1, and the obtained slurry was directly sprayed into the granulation nozzle of a spray dryer granulator for atomization. The pressure of the slurry pump conveying the slurry was 0.3 MPa, the inlet temperature of the spray dryer was 200°C, and the outlet temperature was 140°C to obtain modified boron carbide powder.
[0043] The modified boron carbide powder and aluminum powder were mixed in a mass ratio of 10:100, and ball-milled at a speed of 400 rpm for 5 hours to obtain a mixed powder; dolomite foaming agent and ethanol were added to the mixed powder in a mass ratio of 100:1.5:15. After mixing evenly, the mixture was placed in a mold and pressed at a pressure of 400 MPa. The mixture was then transferred to a sintering furnace, heated to 350°C at a heating rate of 3°C / min, kept warm for 2 hours, and then heated to 650°C at a heating rate of 8°C / min, kept warm for 1 hour, and finally naturally cooled to room temperature to obtain a foamed aluminum shock-absorbing material.
[0044] Example 2
[0045] 1 mol of aluminum isopropoxide was dissolved in 32 mol of ethanol, and after stirring evenly, 80 mol of deionized water was added, and the mixture was placed in a homogenizer, heated to 70° C. for reaction, and after reacting for 3 hours, naturally cooled to room temperature to obtain aluminum sol.
[0046] Boron carbide powder (particle size 1-5 μm) and aluminum sol were mixed in a mass ratio of 0.5:1, and the obtained slurry was directly sprayed into the granulation nozzle of a spray dryer granulator for atomization. The pressure of the slurry pump conveying the slurry was 0.2 MPa, the inlet temperature of the spray dryer was 250°C, and the outlet temperature was 140°C to obtain modified boron carbide powder.
[0047] The modified boron carbide powder and aluminum powder were mixed in a mass ratio of 5:100, and ball milled at a speed of 300 rpm for 6 hours to obtain a mixed powder; dolomite foaming agent and ethanol were added to the mixed powder in a mass ratio of 100:2.0:10, mixed evenly, placed in a mold, and pressed at a pressure of 600 MPa. Subsequently, the mixture was transferred to a sintering furnace, heated to 300°C at a heating rate of 1°C / min, kept warm for 3 hours, and then heated to 700°C at a heating rate of 10°C / min, kept warm for 1.5 hours, and finally naturally cooled to room temperature to obtain a foamed aluminum shock-absorbing material.
[0048] Example 3
[0049] 1 mol of aluminum isopropoxide was dissolved in 32 mol of ethanol, and after stirring evenly, 80 mol of deionized water was added, and the mixture was placed in a homogenizer, heated to 80° C. for reaction. After the reaction lasted for 1 hour, the mixture was naturally cooled to room temperature to obtain aluminum sol.
[0050] Boron carbide powder (particle size 1-5 μm) and aluminum sol were mixed in a mass ratio of 0.8:1, and the obtained slurry was directly sprayed into the granulation nozzle of a spray dryer granulator for atomization. The pressure of the slurry pump conveying the slurry was 0.4 MPa, the inlet temperature of the spray dryer was 180°C, and the outlet temperature was 80°C to obtain modified boron carbide powder.
[0051] The modified boron carbide powder and aluminum powder were mixed in a mass ratio of 15:100, and ball-milled at a speed of 500 rpm for 4 hours to obtain a mixed powder; dolomite foaming agent and ethanol were added to the mixed powder in a mass ratio of 100:1.0:10, mixed evenly, placed in a mold, and pressed at a pressure of 300 MPa. Subsequently, the mixture was transferred to a sintering furnace, heated to 400°C at a heating rate of 5°C / min, kept warm for 1 hour, and then heated to 600°C at a heating rate of 5°C / min, kept warm for 0.5 hour, and finally naturally cooled to room temperature to obtain a foamed aluminum shock-absorbing material.
[0052] Example 4
[0053] The difference from Example 1 is that the mass ratio of the modified boron carbide powder to the aluminum powder is 5:100, and other conditions are the same.
[0054] Example 5
[0055] The difference from Example 1 is that the mass ratio of the modified boron carbide powder to the aluminum powder is 15:100, and other conditions are the same.
[0056] Example 6
[0057] The difference from Example 1 is that dolomite foaming agent and ethanol are added to the mixed powder, wherein the mass ratio of the mixed powder, dolomite foaming agent and ethanol is 100:0.5:15.
[0058] Example 7
[0059] The difference from Example 1 is that dolomite foaming agent and ethanol are added to the mixed powder, wherein the mass ratio of the mixed powder, dolomite foaming agent and ethanol is 100:3:15.
[0060] Comparative Example 1
[0061] The difference from Example 1 is that the foaming agent used is calcium carbonate, and other conditions are the same.
[0062] Comparative Example 2
[0063] Boron carbide powder (particle size 1-5 μm) and aluminum powder are directly mixed in a mass ratio of 10:100, and ball milled at a speed of 400 rpm for 5 hours to obtain a mixed powder; dolomite foaming agent and ethanol are added to the mixed powder in a mass ratio of 100:1.5:15, and after mixing evenly, placed in a mold, pressed at a pressure of 400 MPa, and then transferred to a sintering furnace, heated to 350°C at a heating rate of 3°C / min, kept warm for 2 hours, and then heated to 650°C at a heating rate of 8°C / min, kept warm for 1 hour, and finally naturally cooled to room temperature to obtain a foamed aluminum shock-absorbing material.
[0064] Comparative Example 3
[0065] Dolomite foaming agent and ethanol were added to aluminum powder in a mass ratio of 100:1.5:15. After being evenly mixed, the mixture was placed in a mold and pressed at a pressure of 400 MPa. The mixture was then transferred to a sintering furnace, heated to 350°C at a heating rate of 3°C / min, kept warm for 2 hours, and then heated to 650°C at a heating rate of 8°C / min, kept warm for 1 hour, and finally naturally cooled to room temperature to obtain a foamed aluminum shock-absorbing material.
[0066] Performance Verification
[0067] (1) The tensile strength test refers to GB / T228.1-2010 "Aluminum materials tensile test part 1: room temperature test method", and the compressive yield strength test refers to GB / T 7314-2017 "Metallic materials compression test method at room temperature".
[0068] (2) Porosity determination: Porosity refers to the ratio of pore volume to the overall volume of aluminum foam, that is, the percentage of pores in the total volume. The porosity is usually measured using the water displacement method (first weigh the total mass of the sample, calculate the volume occupied by the aluminum matrix or aluminum alloy matrix based on the density, and then use the Archimedes water displacement method to measure the volume of the foamed sample based on the sample volume measured by the water displacement method, thereby calculating the porosity).
[0069] The test results are shown in Table 1.
[0070] Table 1 Test results
[0071]
[0072]
[0073] As can be seen from Table 1, by comparing Example 1 with Comparative Example 1, it can be seen that the addition of dolomite foaming agent can increase the porosity of the foamed aluminum shock-absorbing material; by comparing Example 1 with Comparative Example 2 and Comparative Example 3, it can be seen that the addition of modified boron carbide powder can further improve the mechanical properties of the foamed aluminum shock-absorbing material.
[0074] As can be seen from the above embodiments, the present invention provides a foam aluminum shock-absorbing material and a preparation method thereof. First, boron carbide powder is immersed in aluminum sol and spray-dried to obtain modified boron carbide powder; the modified boron carbide powder is then mixed with aluminum powder and ball-milled to obtain a mixed powder; finally, the mixed powder, dolomite foaming agent, and ethanol are mixed and sequentially pressed and sintered to obtain a foam aluminum shock-absorbing material. The present invention uses a dolomite foaming agent to replace the traditional calcium carbonate foaming agent. The prepared foam aluminum shock-absorbing material has a finer and more evenly distributed pore structure and has higher energy absorption performance. Modified boron carbide powder is added to the aluminum powder raw material to form a reinforcing phase in the foam aluminum shock-absorbing material, thereby improving the mechanical properties of the foam aluminum shock-absorbing material.
[0075] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.
Claims
1. A method for preparing a foam aluminum shock-absorbing material, characterized in that: The steps include: (1) Immersing boron carbide powder in aluminum sol and preparing modified boron carbide powder by spray drying; (2) mixing the modified boron carbide powder and aluminum powder and then ball milling the mixture to obtain a mixed powder; (3) The mixed powder, dolomite foaming agent and ethanol are mixed and then pressed and sintered in sequence to obtain foamed aluminum shock-absorbing material.
2. The method for preparing the foamed aluminum shock absorbing material according to claim 1, characterized in that: In step (1), the mass ratio of the boron carbide powder to the aluminum sol is 0.5 to 0.8:
1.
3. The method for preparing the foamed aluminum shock absorbing material according to claim 1 or 2, characterized in that: In step (2), the mass ratio of the modified boron carbide powder to the aluminum powder is 5 to 15:
100.
4. The method for preparing the foamed aluminum shock-absorbing material according to claim 3, characterized in that: In step (2), the rotation speed of the ball milling treatment is 300 to 500 rpm, and the time of the ball milling treatment is 4 to 6 hours.
5. The method for preparing the foamed aluminum shock absorbing material according to claim 1, 2 or 4, characterized in that: In step (3), the mass ratio of the mixed powder, dolomite foaming agent and ethanol is 100:0.5~3:10~20.
6. The method for preparing the foamed aluminum shock absorbing material according to claim 5, characterized in that: In step (3), the pressure of the pressing molding is 200 to 600 MPa.
7. The method for preparing the foamed aluminum shock absorbing material according to claim 4 or 6, characterized in that: In step (3), the sintering is carried out in steps, including a first sintering step and a second sintering step.
8. The method for preparing the foamed aluminum shock-absorbing material according to claim 7, characterized in that: The first step of sintering has a heating rate of 1 to 5°C / min, a temperature of 300 to 400°C, and a sintering time of 1 to 3 hours.
9. The method for preparing the foamed aluminum shock-absorbing material according to claim 7, characterized in that: The second step sintering has a heating rate of 5 to 10° C. / min, a temperature of 600 to 700° C., and a sintering time of 0.5 to 1.5 h.
10. The foamed aluminum shock-absorbing material obtained by the method for preparing the foamed aluminum shock-absorbing material according to any one of claims 1 to 9.