Aluminum alloy material preparation device and method

Abstract

The present invention discloses a preparation device and method of aluminum alloy material. The method uses silicon carbide fiber with N-type conductive characteristics as a cathode and graphite as an anode. After heating the electrolyte in the main crucible, the conductivity of the N-type silicon carbide fiber is further increased at high temperature. Voltage is applied to the silicon carbide fiber and the graphite electrode through a power supply until bubbles are formed in the melt. Aluminum melt is formed on the silicon carbide fiber in the electrolytic melt and flows to the substrate. A small part of it is infiltrated on the surface of the silicon carbide fiber. After the electrolysis starts, alloy material is added to the electrolytic melt. A pull-down system is set at the bottom of the electrolytic cell so that the silicon carbide fiber and the aluminum alloy melt solidify into an aluminum alloy continuous silicon carbide fiber composite material. Since each silicon carbide fiber filament is in full contact with the aluminum alloy melt, a well-infiltrated aluminum alloy melt will be formed on the surface, so that a dense aluminum alloy material can be formed.

Description

Technical Field

[0001] The present invention relates to the technical field of methods for preparing aluminum alloy materials, and in particular to a device and method for preparing aluminum alloy materials. Background Art

[0002] Aluminum-based silicon carbide composite materials have low density, low thermal expansion coefficient, high thermal conductivity, high strength and rigidity, good dimensional stability, and excellent front grinding properties. Therefore, they have broad application prospects in aerospace, automobile manufacturing, mechanical processing and other fields. Aluminum-based silicon carbide composite materials produced by existing technologies are prepared by adding silicon carbide particle reinforcement to a stirring container containing molten aluminum alloy, and then stirring in a certain manner to disperse the particles in the aluminum alloy matrix solution. The particles are then injected into a mold of a corresponding shape and pressed at high speed to obtain the finished aluminum-based silicon carbide. However, due to the above method, the silicon carbide particle reinforcement and the aluminum alloy base liquid cannot be completely mixed in a vacuum environment during the stirring process, resulting in uneven density of the finished aluminum-based silicon carbide. Summary of the Invention

[0003] The technical problem to be solved by the present invention is how to provide a device and method for preparing an aluminum alloy material with good infiltration and dense and uniform properties.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a preparation device for aluminum alloy material, comprising a main crucible, wherein the upper and lower ends of the main crucible are formed with openings, a detachable substrate is provided at the lower opening of the main crucible, an adhesive is fixed to the upper surface of the substrate, a crucible rod is provided on the lower surface of the substrate, a first driving device is provided at the lower end of the crucible rod for driving the dry crucible to move up and down, an electromagnetic restraint is provided at the outer periphery of the lower end of the main crucible and the outer periphery of the substrate, a main heater is provided at the outer periphery of the main crucible on the upper side of the electromagnetic restraint; a ring-shaped A graphite anode is provided, the graphite anode is connected to the anode of a DC power supply, a roller is provided outside the upper end opening of the main crucible, the roller is connected to the cathode of the DC power supply, a plurality of strands of N-type silicon carbide fiber are wound on the roller, the lower ends of the N-type silicon carbide fibers are fixed to the adhesive after passing through the anode hole on the graphite anode, an auxiliary crucible is provided on the upper side of the main crucible, an auxiliary heater is provided on the outer periphery of the auxiliary crucible, the upper end of the transmission tube is connected to the auxiliary crucible, the lower end of the transmission tube extends into the main crucible, and the outer end of the roller is connected to a second driving device for driving the roller to rotate.

[0005] The present invention also discloses a method for preparing an aluminum alloy material, which uses the device and comprises the following steps:

[0006] One end of a conductive N-type silicon carbide fiber is wound around a roller connected to the cathode of a DC power supply. The other end of the N-type silicon carbide fiber is first passed through the anode hole in the middle of the graphite anode and then pressed into the middle groove of the base plate with a binder. At the same time, one end of the graphite anode is fixed to an electrode rod, and the other end of the electrode rod is connected to the anode of the DC power supply. Circulating water is set in the base plate to increase cooling function and prevent the binder from loosening due to melting aluminum powder.

[0007] In the initial state, the substrate closes the lower end opening of the main crucible, and electromagnetic restraints are provided around the lower end of the main crucible and the substrate to prevent the melt from flowing out of the gap between the substrate and the crucible or between the crucible and the aluminum alloy material.

[0008] Then, the main crucible is heated to 1000°C by the main heater; the auxiliary crucible is heated to above 1010°C by the auxiliary heater until the mixture of the flux and alumina therein melts and flows into the main crucible through the transfer tube to form an electrolytic melt;

[0009] After the electrolytic melt submerges the graphite anode, the DC power supply is started and the voltage is continuously increased until bubbles form in the melt near the graphite anode. The amount of aluminum formed by electrolysis is calculated based on the current. Aluminum continuously precipitates from the electrolytic melt. When its weight exceeds the surface tension, it flows to the surface of the binder to form aluminum melt. At the same time, during the aluminum electrolysis process, alloy material is added to the auxiliary crucible, melted by heating, and then flows into the crucible to mix with the aluminum melt to form an aluminum alloy melt.

[0010] The pulling rate of the first driving device is controlled based on the amount of aluminum melt formed by the current calculation, so that the amount of aluminum alloy pulled out of the crucible is equal to the value formed by the electrolysis current calculation. As the first driving device moves, the aluminum alloy melt and the N-type silicon carbide fibers solidify together to form an aluminum alloy material matrix.

[0011] As the electrolysis proceeds, alumina and alloy materials are continuously added to the auxiliary crucible, which is then continuously replenished into the main crucible to provide raw materials for the growth of the matrix;

[0012] After the growth of the alloy material aluminum alloy material is completed, the N-type silicon carbide fiber is cut, and all the aluminum alloy melt and electrolytic melt in the main crucible are gradually pulled out of the crucible;

[0013] The electrolytic melt solidified portion and the edge portion of the head of the edge aluminum alloy material matrix are cut off to prepare the aluminum alloy material matrix rod.

[0014] The beneficial effects of the above technical solution are as follows: the device and method utilize N-type conductive silicon carbide fibers as cathodes and graphite as anodes. After heating the electrolyte in the main crucible, the conductivity of the N-type silicon carbide fibers is further increased at high temperatures. A voltage is applied to the silicon carbide fibers and the graphite electrode by a power supply until bubbles are formed in the melt. Aluminum melt is formed on the silicon carbide fibers in the electrolytic melt and flows to the substrate, with a small portion infiltrating the surface of the silicon carbide fibers. After the electrolysis begins, alloy material is added to the electrolytic melt. A pull-down system is provided at the bottom of the electrolytic cell so that the silicon carbide fibers and the aluminum alloy melt solidify into an aluminum alloy material matrix. Since each silicon carbide fiber filament is in full contact with the aluminum alloy melt, a well-infiltrated aluminum alloy melt is formed on the surface, thereby forming a dense aluminum alloy material. The aluminum alloy material prepared by the device and method has the advantages of good infiltration and uniform density. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0016] Figure 1 is a schematic structural diagram of the device before growth according to an embodiment of the present invention;

[0017] Figure 2 is a schematic diagram of the structure of the device in the process of growth according to an embodiment of the present invention;

[0018] Figure 3 1 is a schematic diagram of the three-dimensional structure of the rotating roller in the device according to an embodiment of the present invention;

[0019] Figure 4 is a schematic cross-sectional view of a graphite anode in the device according to an embodiment of the present invention;

[0020] Figure 5 is a schematic cross-sectional structural diagram of a substrate in the device according to an embodiment of the present invention;

[0021] Wherein: 1: main crucible; 2: aluminum alloy melt; 3: graphite anode; 4: aluminum alloy material matrix; 5: N-type silicon carbide fiber; 6: roller; 7: substrate; 8: adhesive; 9: crucible rod; 10: first drive device; 11: DC power supply; 12: second drive device; 13: control system; 14: electrode rod; 15: electromagnetic restrainer; 16: electrolytic melt; 17: main heater; 18: auxiliary heater; 19: auxiliary crucible; 20: mixture of co-solvent and alumina; 21. transmission tube. DETAILED DESCRIPTION

[0022] The following is a clear and complete description of the technical solutions in the embodiments of the present invention, in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts are within the scope of protection of the present invention.

[0023] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0024] like Figure 1 As shown, an embodiment of the present invention discloses a device for preparing aluminum alloy materials, comprising a main crucible 1 having openings formed at the upper and lower ends of the main crucible 1. A detachable substrate 7 is disposed at the lower opening of the main crucible 1. An adhesive 8 is fixed to the upper surface of the substrate 7. Preferably, the thickness of the adhesive 8 is greater than 10 mm. A crucible rod 9 is disposed on the lower surface of the substrate 7. A first drive device 10 is disposed at the lower end of the crucible rod 9 for driving the dry crucible 9 to move up and down. Electromagnetic restraints 15 are disposed on the outer periphery of the lower end of the main crucible 1 and the outer periphery of the substrate 7.

[0025] A circular graphite anode 3 is provided in the main crucible 1. The graphite anode 3 is connected to the anode of the DC power supply 11 through an electrode rod 14. A roller 6 is provided outside the upper opening of the main crucible 1. The roller 6 is connected to the cathode of the DC power supply 11. A plurality of strands of N-type silicon carbide fibers 5 are wound around the roller 6. The lower ends of the N-type silicon carbide fibers 5 pass through the anode hole 3-1 on the graphite anode 3 and are fixed to the adhesive 8. The cross-sectional structure of the graphite anode is shown in FIG. Figure 4 As shown;

[0026] An auxiliary crucible 19 is disposed on the upper right side of the main crucible 1. A mixture 20 of a solubility aid and aluminum oxide is contained within the auxiliary crucible 19. The solubility aid in the mixture 20 of solubility aid and aluminum oxide may be cryolite. An auxiliary heater 18 is disposed on the periphery of the auxiliary crucible 19. The upper end of a transmission tube 21 is connected to the auxiliary crucible 19, and the lower end of the transmission tube 21 extends into the main crucible 1. A second drive device 12 is connected to the outer end of the roller 6 for driving the roller 6 to rotate. A control system 13 is configured to control the first and second drive devices 10, 12 to perform corresponding actions according to a control strategy.

[0027] Further, such as Figure 3As shown, the roller 6 includes a first roller 6-1, a second roller 6-2 and a third roller 6-3. The first roller 6-1, the second roller 6-2 and the third roller 6-3 are arranged in a circular shape, so that the lower ends of the N-type silicon carbide fibers 5 are fixed to the adhesive 8 in an array shape, thereby forming an array of the N-type silicon carbide fibers 5 in the aluminum alloy material matrix 4. In addition, the anode hole 3-1 is larger than the diameter of the array of the N-type silicon carbide fibers 5.

[0028] like Figure 5 As shown, to conveniently accommodate the adhesive 8, a middle groove 7-1 is formed on the substrate 7, and the adhesive 8 is fixed in the middle groove 7-1. Furthermore, a cooling channel is provided in the substrate 7, which is connected to the circulating water system outside the substrate. The circulating water cools the substrate 7, thereby cooling the adhesive 8 on the substrate 7.

[0029] Accordingly, an embodiment of the present invention further discloses a method for preparing an aluminum alloy material, wherein the method uses the preparation device and specifically comprises the following steps:

[0030] One end of a conductive N-type silicon carbide fiber 5 is wound around a roller 6, which is connected to the cathode of a DC power supply 11. The other end of the N-type silicon carbide fiber 5 is first passed through the anode hole 3-1 in the center of the graphite anode 3 and then pressed into the center groove 7-1 of the substrate 7 using a binder 8. At the same time, one end of the graphite anode 3 is fixed to an electrode rod 14, and the other end of the electrode rod is connected to the anode of the DC power supply 11. Circulating water is provided in the substrate 7 to enhance cooling and prevent the binder 8 from loosening due to melting of the aluminum powder.

[0031] In the initial state, if Figure 1 As shown, the substrate 7 closes the lower end opening of the main crucible 1, and an electromagnetic restraint 15 is provided on the outer periphery of the lower end of the main crucible 1 and the outer periphery of the substrate 7. The electromagnetic restraint 15 prevents the melt from flowing out of the gap between the substrate 7 and the crucible 1 or between the crucible 1 and the aluminum alloy material substrate 4;

[0032] Then, the main crucible 1 is heated to 1000° C.-1020° C. by the main heater 17; the auxiliary crucible 19 is heated to above 1010° C. by the auxiliary heater 18 until the mixture 20 of the flux and alumina therein is melted and flows into the main crucible 1 through the transfer pipe to form an electrolytic melt 16;

[0033] After the electrolytic melt 16 submerges the graphite anode 3, the DC power supply 11 is started and the voltage is continuously increased until bubbles form in the melt near the graphite anode 3. The amount of aluminum formed by electrolysis is calculated based on the current. Aluminum is continuously precipitated from the electrolytic melt 16. When the weight exceeds the surface tension, it flows to the surface of the binder 8 to form aluminum melt. Simultaneously, during the aluminum electrolysis process, alloying elements are added to the auxiliary crucible 19, melted by heating, and then flow into the crucible 1 to mix with the aluminum melt, forming an aluminum alloy melt 2.

[0034] The amount of aluminum melt formed by the current calculation is used to control the pulling rate of the first driving device 10 so that the amount of aluminum alloy pulled out of the main crucible 1 is equal to the value formed by the electrolysis current calculation, as shown in FIG. Figure 2 As shown, with the movement of the first driving device 10, the aluminum alloy melt 2 and the N-type silicon carbide fiber 5 solidify together to form an aluminum alloy material matrix 4 (that is, the amount of aluminum alloy formed is equal to the amount of aluminum alloy pulled out of the main crucible, to prevent the pulling speed from being too slow or too fast to affect the aluminum alloy material matrix 4);

[0035] As the electrolysis proceeds, alumina and alloy materials are continuously added to the auxiliary crucible 19, and then continuously replenished into the main crucible 1, providing raw materials for the growth of the matrix;

[0036] After the growth is completed, the N-type silicon carbide fiber 5 is cut off, and all the aluminum alloy melt 2 and the electrolytic melt 16 in the main crucible 1 are gradually pulled out of the crucible 1;

[0037] The solidified portion of the electrolytic melt 16 and the edge portion of the head of the edge aluminum alloy material matrix 4 are cut off to prepare a rod of the aluminum alloy material matrix 4.

[0038] In this application, the carbon body is used as the anode and the aluminum liquid is used as the cathode. The reaction formula is: 2Al2O3==4Al+3O2, and the anode reaction formula is: 2O 2 ˉ-4eˉ=O2; The interfacial bonding between silicon carbide fibers and the aluminum matrix seriously affects the performance of aluminum-based silicon carbide composite materials. In the present application, N-type silicon carbide crystals with a resistivity of less than 0.01Ω·cm can be obtained by highly doping with elements such as nitrogen and aluminum. As the temperature of the method described in the present application increases, the excitation of electrons and holes in silicon carbide increases, resulting in increased conductivity and reduced resistance, which provides a basis for the electrolysis of aluminum. Each silicon carbide fiber filament in each strand is in contact with each other, and a well-infiltrated aluminum alloy melt will be formed on the surface, thereby forming a dense aluminum alloy material. The aluminum alloy material prepared by the device and method has the advantages of good infiltration and uniform density.

Claims

1. A device for preparing aluminum alloy material, characterized in that: The invention comprises a main crucible (1), wherein the upper and lower ends of the main crucible (1) are formed with openings, a detachable substrate (7) is arranged at the lower opening of the main crucible (1), an adhesive (8) is fixed to the upper surface of the substrate (7), a crucible rod (9) is arranged on the lower surface of the substrate (7), a first driving device (10) is arranged at the lower end of the crucible rod (9) for driving the crucible rod (9) to move up and down, an electromagnetic restraint (15) is arranged on the outer periphery of the lower end of the main crucible (1) and the outer periphery of the substrate (7), and a main heater (17) is arranged on the outer periphery of the main crucible (1) on the upper side of the electromagnetic restraint (15); a circular graphite anode (3) is arranged in the main crucible (1), and the graphite anode (3) is connected to the anode of a DC power supply (11). A roller (6) is arranged outside the upper opening of the main crucible (1), the roller (6) is connected to the cathode of a direct current power source (11), a plurality of strands of N-type silicon carbide fibers (5) are wound around the roller (6), the lower ends of the N-type silicon carbide fibers (5) are fixed to the binder (8) after passing through the anode holes (3-1) on the graphite anode (3), an auxiliary crucible (19) is arranged on the upper side of the main crucible (1), an auxiliary heater (18) is arranged on the outer periphery of the auxiliary crucible (19), the upper end of a transmission tube (21) is connected to the auxiliary crucible (19), the lower end of the transmission tube (21) extends into the main crucible (1), and the outer end of the roller (6) is connected to a second driving device (12) for driving the roller (6) to rotate; One end of an N-type silicon carbide fiber (5) having a conductive property is wound around a roller (6), and the roller (6) is connected to the cathode of a direct current power source (11); the other end of the N-type silicon carbide fiber (5) first passes through the anode hole (3-1) in the middle of the graphite anode (3), and then is pressed into the middle groove (7-1) of the substrate (7) through a binder (8), and at the same time, one end of the graphite anode (3) is fixed to an electrode rod (14), and the other end of the electrode rod (14) is connected to the anode of the direct current power source (11); circulating water is set in the substrate (7) to increase the cooling function and prevent the binder (8) from loosening due to the melting of aluminum powder; In the initial state, the substrate (7) closes the lower end opening of the main crucible (1), and an electromagnetic restraint (15) is provided on the outer periphery of the lower end of the main crucible (1) and the outer periphery of the substrate (7), so that the molten metal is prevented from flowing out of the gap between the substrate (7) and the main crucible (1) or between the main crucible (1) and the aluminum alloy material matrix (4); Then, the main crucible (1) is heated to 1000° C.-1020° C. by a main heater (17); the auxiliary crucible (19) is heated to above 1010° C. by an auxiliary heater (18) until the mixture (20) of the auxiliary solvent and alumina therein is melted and flows into the main crucible (1) through a transfer pipe to form an electrolytic melt (16); After the electrolytic melt (16) has submerged the graphite anode (3), the DC power supply (11) is started and the voltage is continuously increased until bubbles are formed in the melt near the graphite anode (3), and the amount of aluminum formed by electrolysis is calculated according to the current. Aluminum is continuously precipitated from the electrolytic melt (16), and when the weight is greater than the surface tension, it flows to the surface of the binder (8) to form aluminum melt; at the same time, during the process of electrolyzing aluminum, alloy material is added to the auxiliary crucible (19), which is heated and melted and then flows to the main crucible (1) to mix with the aluminum melt to form an aluminum alloy melt (2); According to the amount of aluminum alloy melt formed by current calculation, the pulling-down rate of the first driving device (10) is controlled, so that the amount of aluminum alloy melt pulled out of the main crucible (1) is equal to the value formed by the electrolysis current calculation, and as the first driving device (10) moves, the aluminum alloy melt (2) and the N-type silicon carbide fiber (5) solidify together to form an aluminum alloy material matrix (4); As the electrolysis proceeds, alumina and alloy materials are continuously added to the auxiliary crucible (19), and then continuously added to the main crucible (1), thereby providing raw materials for the growth of the matrix; After the growth is completed, the N-type silicon carbide fibers (5) are cut off, and all the aluminum alloy melt (2) and the electrolytic melt (16) in the main crucible (1) are gradually pulled out of the main crucible (1); The solidified part and the edge part of the electrolytic melt (16) at the head of the aluminum alloy material matrix (4) are cut off to prepare an aluminum alloy material matrix (4) rod.

2. The device for preparing the aluminum alloy material according to claim 1, characterized in that: The device further comprises a control system (13), wherein the control system (13) is used to control the first drive device (10) and the second drive device (12) to perform corresponding actions according to a control strategy.

3. The device for preparing the aluminum alloy material according to claim 1, characterized in that: The rollers (6) comprise a first roller (6-1), a second roller (6-2) and a third roller (6-3), so that the lower ends of the N-type silicon carbide fibers (5) are fixed to the binder (8) in an array shape, thereby forming an array of the N-type silicon carbide fibers (5) in the aluminum alloy material matrix (4).

4. The device for preparing the aluminum alloy material according to claim 1, characterized in that: The thickness of the adhesive (8) is greater than 10 mm.

5. The device for preparing the aluminum alloy material according to claim 1, characterized in that: A middle groove (7-1) is formed on the substrate (7), and the adhesive (8) is fixed in the middle groove (7-1).

6. The device for preparing the aluminum alloy material according to claim 1, characterized in that: A cooling channel is provided in the substrate (7), and the cooling channel is connected to a circulating water system outside the substrate (7). The substrate (7) is cooled by circulating water, thereby cooling the adhesive (8) on the substrate (7).

7. The device for preparing the aluminum alloy material according to claim 1, characterized in that: The room temperature resistivity of the N-type silicon carbide fiber (5) is less than 0.01Ω·cm.

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