Preparation method of medium-low volume fraction particle reinforced aluminum-based composite material
Through the method of cold isostatic pressing and direct hot extrusion under high temperature vacuum, the problems of expensive equipment and long cycle in the preparation of medium and low volume aluminum-based composite materials are solved, low-cost and efficient material preparation is achieved, and the high performance of the material is maintained.
Patent Information
- Application Number
- CN202510745202.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-05
- Publication Date
- 2025-09-12
AI Technical Summary
In the existing preparation process of medium and low volume fraction aluminum-based composite materials, expensive vacuum hot pressing furnaces and hot isostatic pressing furnaces are required, resulting in high production costs and long cycles.
After densification by cold isostatic pressing, hot extrusion is directly carried out under high temperature vacuum, combined with aluminum sheath packaging and vacuum degassing to achieve synchronization of powder densification and plastic forming, avoiding the use of expensive equipment and shortening the production cycle.
The low-cost preparation of medium and low volume fraction particle reinforced aluminum matrix composites was achieved, which improved production efficiency, reduced energy consumption and maintained the high performance of the materials.
Smart Images
Figure CN120624877A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the field of composite material preparation, and in particular relates to a method for preparing a medium- and low-volume fraction particle-reinforced aluminum-based composite material. Background Art
[0002] Medium and low volume fraction aluminum-based composite materials (volume fraction ≤ 35%) are an important direction for upgrading the performance of traditional aluminum alloys. Their development background and technological progress are closely related to the urgent demand of modern industry for lightweight and high-performance materials.
[0003] Hot extrusion is crucial for low- to medium-volume composites. Through its unique combination of high pressure, high temperature, and directional plastic deformation, the extrusion process optimizes the physical and mechanical properties of low- to medium-volume composites. The applied pressure during the extrusion process promotes plastic deformation, effectively eliminating pores and microscopic defects in the raw powder or billet, fostering close contact between the reinforcement and the matrix. Furthermore, directional plastic deformation results in an ordered, diffuse distribution of the reinforcement within the matrix, significantly improving longitudinal strength and modulus.
[0004] Powder metallurgy requires high-temperature sintering of the composite material, followed by hot pressing and densification before hot extrusion to produce the extruded material. This process requires the composite material to be sintered and hot pressed in a vacuum hot press or hot isostatic pressing furnace, then cooled and hot extruded again, increasing energy consumption and production cycle time.
[0005] In summary, there is a need for a low-cost, short-process method for preparing medium- and low-volume particle-reinforced aluminum-based composites. This method, which combines powder densification with plastic forming in a single, continuous process through simultaneous hot pressing and extrusion, offers the potential for both efficiency and performance optimization. This method, which allows for simultaneous plastic forming during dynamic densification, avoids the use of expensive vacuum hot pressing and hot isostatic pressing furnaces, shortens production cycles, and reduces production costs. Summary of the Invention
[0006] The embodiment of the present invention provides a method for preparing a medium- and low-volume fraction particle-reinforced aluminum-based composite material, aiming to solve the problems in the prior art.
[0007] The embodiment of the present invention is implemented as follows:
[0008] A method for preparing a medium- and low-volume particle reinforced aluminum-based composite material, comprising:
[0009] Step (1): placing aluminum-based composite material powder into a cold isostatic pressing package for cold isostatic pressing densification;
[0010] Step (2): encapsulating the densified blank with an aluminum sheath, degassing at high temperature, and sealing;
[0011] Step (3): heating the encapsulated billet at a high temperature to cause metallurgical reaction of the alloying elements in the aluminum matrix;
[0012] Step (4): After sintering, the composite material is transferred to a low-temperature heating furnace for continued heat preservation. After heat preservation, the composite material is transferred to an extrusion barrel for rapid extrusion to obtain a medium-low volume fraction particle reinforced aluminum-based composite extrusion material.
[0013] Furthermore, in step (1), the particle-reinforced aluminum-based composite material powder is mixed, the reinforcing phase particles are B4C, Si, SiC, Al2O3, etc., and the volume content of the reinforcing phase particles is 10-35%, preferably 15-30%; the matrix alloy powder is pure Al, Al-Cu-Mg system or Al-Cu-Mg-Si system.
[0014] Furthermore, in step (1), the diameter of the cold isostatic pressing mold is between 500-900 mm, and the cold isostatic pressing process is 20-50 MPa with a holding time of 480-720 s; 100-120 MPa with a holding time of 300-600 s; 180-200 MPa with a holding time of 600-900 s.
[0015] Furthermore, in step (2), the packaging material is 1060, 1100 or 6061, 6092 aluminum alloy, and an aluminum alloy with a thickness of 20-50 mm is used on any end face of the billet (front end face), and an aluminum alloy with a thickness of 10-15 mm is used on the side and the other end face (rear end face). It is sealed by welding, and the exhaust hole is ensured to be on the rear end face.
[0016] Furthermore, in step (2), the high-temperature degassing temperature is 400-500°C, and when the vacuum degree is 1×10 -2 Pa to 5×10 -1 Pa range, continue to keep warm for 2-10 hours, and then seal.
[0017] Furthermore, in step (3), the sintering temperature of the packaged blank is 560-620° C., and the holding time is 5-20 h.
[0018] Furthermore, the aluminum-based composite material in step (4) is transferred to a low-temperature heating furnace and kept warm at a temperature of 440-520° C. for 4-8 hours.
[0019] Furthermore, in step (4), the front end surface of the aluminum-based composite material is placed close to the die and the rear end surface is placed close to the extrusion axis, the extrusion speed is 5-15 mm / s, the extrusion ratio is (20-30):1, and the inlet angle of the extrusion die is 45±5°.
[0020] The present invention offers the following advantages: After cold isostatic pressing of uniformly mixed aluminum-based composite powder, hot extrusion is performed directly under high temperature and vacuum conditions, achieving densification during the plastic deformation of the composite material, directly yielding a high-performance extruded material. This short-process preparation method avoids the use of expensive hot isostatic pressing and vacuum hot pressing equipment, lowering the barrier to composite material production. Furthermore, it avoids the need for reheating the composite ingot, shortening the composite material production cycle and reducing energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 This is the OM image of 35% SiC / 6092Al along the extrusion direction of Example 1 of the present invention;
[0022] Figure 2 This is a powder metallurgy method and hot extrusion imaging diagram of Example 1 of the present invention;
[0023] Figure 3 Schematic diagram of the microscopic morphology of 27% Si / Al in Example 2 of the present invention;
[0024] Figure 4 This is a diagram of powder metallurgy and hot extrusion imaging according to the second embodiment of the present invention;
[0025] Figure 5 This is the OM image of 15% SiC / 2009Al along the extrusion direction of Example 3 of the present invention
[0026] Figure 6 This is a powder metallurgy method and hot extrusion imaging diagram of Example 3 of the present invention. DETAILED DESCRIPTION
[0027] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.
[0028] Example 1:
[0029] See also Figure 1-Figure 2 Step (1): Prepare aluminum-based composite material powder with a volume fraction of SiC particles of 35%, 230 kg of 6092Al matrix alloy powder, and place the powder into a polyurethane mold with a diameter of 500 mm and a height of 900 mm for cold isostatic pressing. The cold isostatic pressing process is to maintain a pressure of 20 MPa for 480 seconds, then pressurize to 120 MPa for 300 seconds, and continue to pressurize to 180 MPa for 600 seconds. After the pressure is maintained, take out the formed composite material, the specification of which is a billet of φ430 mm×765 mm.
[0030] Step (2): The cold isostatically pressed blank is sealed with 6061Al, wherein the thickness of the side aluminum sheath is 15mm and the shape is rolled into the corresponding size according to the specifications of the blank using a plate rolling machine. The front end face uses a φ460mm×50mm aluminum pad, and the rear end face uses a φ460mm×15mm thick aluminum pad. Argon arc welding is used to seal all places, and a hole is opened on the rear end face. The air tightness test of the welding position is carried out by pressing, and high-temperature sealing is performed after there is no air leakage.
[0031] Step (3): First, connect the blank of the package to the vacuum pump to exhaust the residual gas in the package. When the vacuum degree is lower than 10 2 Pa, the temperature was raised and kept at 500℃ for 3h. The vacuum degree was 2.1×10 -2 Pa, and the vacuum degree is counted every hour. After 3 hours of heat preservation, the package is sealed from the exhaust pipe, and the blank is air-cooled to room temperature.
[0032] Step (4): Place the blank of the package into a heating furnace for heating. Heat the temperature to 620°C in 5 hours and then keep it warm for 5 hours. After the insulation is completed, use a clamp car to quickly transfer the composite material to a low-temperature heating furnace. Start timing after the temperature of the heating furnace stabilizes and keep it warm at 520°C for 4 hours.
[0033] Step (5): To ensure smooth extrusion, a die with an inlet angle of 45° was used for extrusion. After the insulation was completed, the billet was quickly transferred to the extrusion barrel for extrusion at an extrusion speed of 5 mm / s and an extrusion ratio of 20:1 to obtain an extruded rod of φ102 mm × 9.5 m.
[0034] The mechanical (T6 state) and thermophysical properties and micromorphology of the 35% SiC / 6092Al composite material prepared by this embodiment were compared with those prepared by traditional powder metallurgy + hot extrusion. The results are as follows: it was found that the differences in various properties were not significant, and the SiC particles were evenly distributed without obvious holes and cracks.
[0035] The specific data of Example 1 are shown in the following table
[0036]
[0037] Example 2:
[0038] See also Figure 3-Figure 4Step (1): Prepare aluminum-based composite material powder with a Si particle mass fraction of 27%, 380 kg of pure Al powder as the matrix alloy, and load the powder into a polyurethane mold with a diameter of 720 mm and a height of 900 mm for cold isostatic pressing. The cold isostatic pressing process is to maintain the pressure at 40 MPa for 600 s, then increase the pressure to 100 MPa for 400 s, and continue to increase the pressure to 190 MPa for 800 s. After the pressure is maintained, the formed composite material is taken out, with a specification of φ640 mm×560 mm.
[0039] Step (2): The cold isostatically pressed blank is sealed with 1060Al, wherein the side aluminum sheath is 10mm thick and is rolled into a corresponding arc shape according to the specifications of the blank using a plate rolling machine. The front end face uses a φ660mm×30mm aluminum pad, and the rear end face uses a φ660mm×10mm thick aluminum pad. Argon arc welding is used to seal each part, and a hole is opened on the rear end face for airtightness testing. After no air leakage, high-temperature sealing is performed.
[0040] Step (3): First, connect the blank of the package to the vacuum pump to exhaust the residual gas in the package. When the vacuum degree is less than 10 2 Pa, the temperature was raised and kept at 400℃ for 2h. The vacuum degree was 4.4×10 -1 Pa, and the vacuum degree is counted every hour. After 10 hours of heat preservation, the package is sealed from the exhaust pipe, and the blank is air-cooled to room temperature.
[0041] Step (4): Place the blank of the package sleeve into a heating furnace for heating. After heating to 560°C for 5 hours, keep it warm for 10 hours. After the insulation is completed, use a clamp car to quickly transfer the composite material to a low-temperature heating furnace. Start timing after the temperature of the heating furnace stabilizes and keep it warm at 480°C for 6 hours.
[0042] Step (5): To ensure smooth extrusion, a die with an extrusion angle of 45 degrees was used for extrusion. After the insulation was completed, the billet was quickly transferred to the extrusion barrel for extrusion at an extrusion speed of 10 mm / s and an extrusion ratio of 25:1 to obtain an extruded rod of φ130 mm×10.5 m.
[0043] The mechanical (annealed state) and thermophysical properties and micromorphology of the 27% Si / Al composite material prepared by this embodiment were compared with those of the 27% Si / Al prepared by traditional powder metallurgy + hot extrusion. The results are as follows: it was found that the differences in various properties were not significant, and the Si particles were evenly distributed without obvious holes and cracks.
[0044] The specific data of Example 2 is shown in the figure below
[0045]
[0046]
[0047] Example 3:
[0048] See also Figure 5-Figure 6 Step (1): Prepare aluminum-based composite material powder with a volume fraction of SiC particles of 15%, 340 kg of powder of the matrix alloy 2009, and put the powder into a polyurethane mold with a diameter of 860 mm and a height of 550 mm for cold isostatic pressing. The cold isostatic pressing process is 50 MPa holding pressure for 720 seconds, then pressurizing to 100 MPa holding pressure for 600 seconds, and continuing to pressurize to 200 MPa holding pressure for 900 seconds. After the holding pressure is completed, the formed composite material is taken out, with a specification of φ775 mm×345 mm.
[0049] Step (2): The cold isostatically pressed blank is sealed with 6061Al, wherein the side aluminum sheath is 10mm thick and is rolled into a corresponding arc shape according to the specifications of the blank using a plate rolling machine. The front end face uses a φ785mm×20mm aluminum pad, and the rear end face uses a φ785mm×10mm thick aluminum pad. Argon arc welding is used to seal each part, and a hole is opened on the rear end face for airtightness testing. After no air leakage, high-temperature sealing is performed.
[0050] Step (3): First, connect the blank of the package to the vacuum pump to exhaust the residual gas in the package. When the vacuum degree is less than 10 2 Pa, the temperature was raised and kept at 450℃ for 6 hours. The vacuum degree was 1.3×10 -2 Pa, and the vacuum degree is counted every hour. After 20 hours of heat preservation, the package is sealed from the exhaust pipe, and the blank is air-cooled to room temperature.
[0051] Step (4): Place the blank of the package sleeve into a heating furnace for heating. After heating to 610°C for 10 hours, keep the temperature for 20 hours. After the insulation is completed, use a clamp car to quickly transfer the composite material to a low-temperature heating furnace. Start timing after the temperature of the heating furnace stabilizes and keep it at 440°C for 8 hours.
[0052] Step (5): To ensure smooth extrusion, a die with an extrusion angle of 45 degrees was used for extrusion. After the insulation was completed, the billet was quickly transferred to the extrusion barrel for extrusion at an extrusion speed of 15 mm / s and an extrusion ratio of 30:1 to obtain an extruded rod of φ143 mm × 7.2 m.
[0053] The mechanical (T4) and thermophysical properties and micromorphology of the 15% SiC / 2009Al composite material prepared by this embodiment were compared with those of the 15% SiC / 2009Al prepared by traditional powder metallurgy + hot extrusion. The results are as follows: it was found that the differences in various properties were not significant, and the SiC particles were evenly distributed without obvious holes and cracks.
[0054] Specific data table of Example 3
[0055]
[0056] Throughout this specification, references to terms such as "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" indicate that a specific feature, structure, material, or characteristic described in conjunction with an embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
[0057] In addition, the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A method for preparing a medium- and low-volume particle reinforced aluminum matrix composite material, characterized in that: The following steps are involved: Step (1): placing aluminum-based composite material powder into a cold isostatic pressing package for cold isostatic pressing densification; Step (2): encapsulating the densified blank with an aluminum sheath, degassing at high temperature, and sealing; Step (3): heating the encapsulated billet at a high temperature to cause metallurgical reaction of the alloying elements in the aluminum matrix; Step (4): After sintering, the composite material is transferred to a low-temperature heating furnace for continued heat preservation. After heat preservation, the composite material is transferred to an extrusion barrel for rapid extrusion to obtain a medium-low volume fraction particle reinforced aluminum-based composite extrusion material.
2. The method for preparing a medium- and low-volume fraction particle-reinforced aluminum-based composite material according to claim 1, characterized in that: In the particle-reinforced aluminum-based composite material powder, the reinforcing phase particles are B4C, Si, SiC, and AlO, and the volume content of the reinforcing phase particles is 10-35%; the matrix alloy powder is Al, Al-Cu-Mg series, or Al-Cu-Mg-Si series.
3. The method for preparing a medium- and low-volume particle reinforced aluminum-based composite material according to claim 1, characterized in that: The diameter of the cold isostatic pressing die is between 500-900 mm, and the cold isostatic pressing process is 20-50 MPa with a holding time of 480-720 s; 100-120 MPa with a holding time of 300-600 s; 180-200 MPa with a holding time of 600-900 s.
4. The method for preparing a medium- and low-volume fraction particle-reinforced aluminum-based composite material according to claim 1, characterized in that: The packaging material is 1060, 1100 or 6061, 6092 aluminum alloy. A 20-50 mm thick aluminum alloy is used on any end face of the billet (front end face), and a 10-15 mm thick aluminum alloy is used on the side and the other end face (rear end face). It is sealed by welding and the exhaust hole is ensured to be on the rear end face.
5. The method for preparing a medium- and low-volume fraction particle-reinforced aluminum-based composite material according to claim 1, characterized in that: The high-temperature degassing temperature is 400-500°C, and when the vacuum degree is 1×10 -2 Pa to 5×10 -1 Pa range, continue to keep warm for 5-10 hours, and then seal.
6. The method for preparing a medium- and low-volume fraction particle-reinforced aluminum-based composite material according to claim 1, characterized in that: The sintering temperature of the packaged blank is 560-620° C., and the holding time is 5-20 hours.
7. The method for preparing a medium- and low-volume fraction particle-reinforced aluminum-based composite material according to claim 1, characterized in that: The aluminum-based composite material is transferred to a low-temperature heating furnace and is kept warm at a temperature of 440-520° C. for 4-8 hours.
8. The method for preparing a medium- and low-volume fraction particle-reinforced aluminum-based composite material according to claim 1, characterized in that: The front end surface of the aluminum-based composite material is close to the die, and the rear end surface is close to the extrusion axis. The extrusion speed is 5-15 mm / s, the extrusion ratio is (20-30):1, and the inlet angle of the extrusion die is 45±5°.