Preparation equipment and method for rheological die casting of nano-modified aluminum-based composite materials

Abstract

The present invention discloses a preparation device and method for rheological die casting of nano-modified aluminum-based composite materials, which relates to the technical field of composite materials. The key points of the technical solution are: including an insulated molten pool, a material spoon, a stirring device, a transmission device for controlling the movement of the material spoon, a semi-solid slurrying device for filling the material spoon with inert gas, a wire feeding device and a die casting device; the wire feeding device is used to feed the wire into the material spoon, and the die casting device is used to die-cast the composite material; the stirring device includes an insulated graphite crucible and an electromagnetic stirring induction coil, and the electromagnetic stirring induction coil is embedded in the insulated graphite crucible; the end of the transmission device is connected to the side wall of the material spoon to transfer the aluminum alloy melt in the insulated molten pool to the insulated graphite crucible. The device and method solve the problem that the existing nano-enhanced phase is difficult to be evenly dispersed in the aluminum matrix, and have high economic efficiency; the process is simple, and high-quality nano-modified aluminum-based composite materials can be prepared.

Description

Technical Field

[0001] The invention relates to the technical field of composite materials, and more specifically to a preparation device and a method for rheological die-casting of nano-modified aluminum-based composite materials. Background Art

[0002] Aluminum is a metal with low strength and good plasticity. In addition to the application of some pure aluminum, it is also alloyed to improve strength or comprehensive performance. Adding an alloy element to aluminum can change its structure and performance, making it suitable for various processing materials or casting parts.

[0003] At present, in order to prepare aluminum-based composite parts with excellent performance, the common problems of composite materials, such as poor wettability between the reinforcement phase and the matrix and uneven distribution, are addressed. Some patents propose adding the reinforcement phase to the molten metal matrix alloy by electromagnetic stirring, but due to the skin effect, the structure of the composite material varies from place to place and it is difficult to make it uniform. Some patents mix the reinforcement particles and aluminum powder by ball milling and then add them to the molten pool, which is expensive. It is difficult to achieve both reliability and economy of materials in existing technologies. Summary of the invention

[0004] The purpose of the present invention is to provide a preparation device and method for rheological die casting of nano-modified aluminum-based composite materials. The device and method solve the problem that the existing nano-reinforced phase is difficult to be evenly dispersed in the aluminum matrix, and have high economic efficiency; the process is simple, and high-quality nano-modified aluminum-based composite materials can be prepared.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions: a preparation device for rheological die-casting of nano-modified aluminum-based composite materials, comprising a heat-insulating molten pool, a material spoon, a stirring device, a transmission device for controlling the movement of the material spoon, a semi-solid slurrying device for filling the material spoon with inert gas, a wire feeding device and a die-casting device; the wire feeding device is used to feed the wire material into the material spoon, and the die-casting device is used to die-cast the composite material;

[0006] The stirring device comprises a heat-insulating graphite crucible and an electromagnetic stirring induction coil, wherein the electromagnetic stirring induction coil is embedded in the heat-insulating graphite crucible;

[0007] The end of the transmission device 1 is connected to the side wall of the material spoon to transfer the aluminum alloy melt in the heat-insulating molten pool to the heat-insulating graphite crucible;

[0008] The semi-solid pulping device comprises an air inlet pipe, an air storage tank and a graphite air outlet rod; the air inlet pipe is fixedly connected to the air inlet end of the air storage tank, the air outlet end of the air storage tank is connected to the graphite air outlet rod, and the air outlet end of the graphite air outlet rod is located in a material spoon placed in a heat-insulating graphite crucible;

[0009] The die-casting device includes a barrel, a push rod, a pressure head, a plurality of ultrasonic probes and a molding device; the plurality of ultrasonic probes are embedded in the side wall of the barrel, the end of the push rod is connected to the pressure head, the pressure head is located in the barrel and is slidably connected to the inner wall of the barrel; a feed port is opened on the side wall of the barrel, and the discharge end of the barrel is connected to the inside of the molding device.

[0010] Further: the molding device includes a left mold, a right mold and a second transmission device; a cavity is opened at the closed part of the left mold and the right mold, and the cavity is connected to the discharge end of the barrel; the second transmission device is used to control the closing of the left mold and the right mold.

[0011] Further: the second transmission device includes a guide rod, a hydraulic rod, a transmission, two support frames and two pulleys; the side wall of one of the support frames is fixedly connected to the outer side wall of the right mold, the support frame is fixedly connected to the end of the hydraulic rod, the transmission connects the two support frames, and the bottom of the two support frames is slidably connected to the guide rod; the outer bottom of the left mold is fixedly connected to the guide rod.

[0012] Furthermore: the wire feeding device includes an induction heating coil for heating the wire and a stop valve; the stop valve is used to control the amount of wire fed into the feeding spoon.

[0013] Furthermore: the transmission device 1 includes a baffle, a first transmission rod and a second transmission rod; the side walls of the first transmission rod close to both ends are hinged to the side walls of the baffle and the side walls of the second transmission rod respectively.

[0014] Furthermore: it also includes a transmission device three for controlling the up and down movement of the semi-solid pulping device, and the transmission device three includes a third transmission rod, a screw rod and a fixed flange; the fixed flange is fixedly sleeved on the graphite air outlet rod and fixedly connected to the screw rod, and the end of the screw rod is movably connected to the third transmission rod.

[0015] The present invention also provides a preparation method of nano-modified aluminum-based composite material by rheological die casting, which specifically comprises the following steps:

[0016] S1: The aluminum alloy melt is transferred to a heat preservation molten pool and the temperature is controlled at 20-50°C at the liquidus;

[0017] S2: Take the material with a material spoon and transfer it to a heat-insulating graphite crucible, turn on the electromagnetic stirring coil for stirring, and feed the composite material wire at the same time. After the feeding is completed, keep the electromagnetic stirring for 2-5 minutes;

[0018] S3: Control the graphite outlet rod of the semi-solid pulping device to be inserted into the material spoon, and start the inert gas blowing for 3-10 seconds;

[0019] S4: pouring the melt into the barrel, turning on ultrasonic vibration, and preheating the mold in advance; then injecting the melt into the mold to obtain an aluminum-based composite die-casting with a uniform distribution of reinforcement phase.

[0020] Further: when feeding the composite material in S2, the wire temperature needs to be heated to 10-30° C. below the solidus.

[0021] Furthermore: the preheating temperature of the mold in S4 is 300-400°C.

[0022] In summary, the present invention has the following beneficial effects:

[0023] 1. The wire feeding device feeds the prefabricated high-volume composite material into the aluminum melt. Under the action of electromagnetic stirring, the composite wire and the aluminum melt are fully mixed, and the nano-reinforced phase is evenly distributed in the melt;

[0024] 2. Inserting the graphite outlet rod into the melt of the spoon can significantly improve the skin effect of electromagnetic stirring. In addition, a large amount of inert gas is introduced into the graphite outlet rod to produce strong stirring and rapid heat dissipation. The bubble rupture induces melt nucleation and completes semi-solid pulping.

[0025] 3. An ultrasonic probe is embedded in the inner wall of the barrel, and the melt is added into the barrel at the same time. During the first stage of pressurization, the melt is subjected to cavitation, which effectively breaks up the reinforcement phase clusters and achieves dispersed distribution. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic structural diagram of the preparation equipment for rheological die-casting of nano-modified aluminum-based composite materials in Example 1 of the present invention.

[0027] In the figure: 1. aluminum alloy melt; 2. insulation molten pool; 3. baffle; 4. first transmission rod; 5. second transmission rod; 6. material spoon; 7. electromagnetic stirring induction coil; 8. insulation graphite crucible; 9. screw rod; 10. third transmission rod; 11. fixed flange; 12. air inlet pipe; 13. gas storage tank; 14. graphite air outlet rod; 15. composite material wire; 16. induction heating coil; 17. stop valve; 18. push rod; 19. pressure head; 20. barrel; 21. feed port; 22. ultrasonic probe; 23. left mold; 24. right mold; 25. cavity; 26. hydraulic rod; 27. guide rod; 28. support frame; 29. ​​transmission; 30. pulley. DETAILED DESCRIPTION

[0028] The following is combined with Figure 1 The present invention is described in further detail.

[0029] Example 1: Preparation equipment for rheological die casting of nano-modified aluminum-based composite materials, such as Figure 1As shown, it includes a heat preservation molten pool 2, a material spoon 6, a stirring device, a transmission device for controlling the movement of the material spoon 6, a semi-solid slurry making device for filling the material spoon 6 with inert gas, a wire feeding device and a die-casting device; the wire feeding device is used to feed the wire material into the material spoon 6, and the die-casting device is used to die-cast the composite material;

[0030] The stirring device comprises a heat-insulating graphite crucible 8 and an electromagnetic stirring induction coil 7, wherein the electromagnetic stirring induction coil 7 is embedded in the heat-insulating graphite crucible 8;

[0031] The end of the transmission device 1 is connected to the side wall of the scoop 6 to transfer the aluminum alloy melt 1 in the heat-insulating molten pool 2 to the heat-insulating graphite crucible 8;

[0032] The semi-solid pulping device comprises an air inlet pipe 12, an air storage tank 13 and a graphite air outlet rod 14; the air inlet pipe 12 is fixedly connected to the air inlet end of the air storage tank 13, the air outlet end of the air storage tank 13 is connected to the graphite air outlet rod 14, and the air outlet end of the graphite air outlet rod 14 can be moved to the material spoon 6 in the heat-insulating graphite crucible 8 by the action of the transmission device 3; the air storage tank 13 is filled with inert gas, and then the inert gas is sprayed into the melt in the material spoon 6 through the graphite air outlet rod 14, which can significantly improve the skin effect existing in electromagnetic stirring, and a large amount of inert gas is introduced to produce strong stirring effect and rapid heat dissipation, and the bubble ruptures to induce melt nucleation, thereby completing semi-solid pulping;

[0033] The die-casting device includes a barrel 20, a push rod 18, a pressure head 19, a plurality of ultrasonic probes 22 and a molding device; the plurality of ultrasonic probes 22 are embedded in the side wall of the barrel 20, and can perform ultrasonic vibration on the melt in the barrel 20. The end of the push rod 18 is connected to the pressure head 19, and the pressure head 19 is located in the barrel 20 and is slidably connected to the inner wall of the barrel 20; a feed port 21 is opened on the side wall of the barrel 20 near its end. When the melt needs to be injected into the barrel 20, the pressure head 19 needs to be slid to the end of the barrel 20, the melt is added from the position of the feed port 21, and then the melt is pushed forward by the pressure head 19, and the discharge end of the barrel 20 is connected to the inside of the molding device.

[0034] The molding device includes a left mold 23, a right mold 24 and a second transmission device; a cavity 25 is opened at the closed part of the left mold 23 and the right mold 24, and the cavity 25 is connected to the discharge end of the barrel 20; the second transmission device is used to control the closing of the left mold 23 and the right mold 24.

[0035] The second transmission device includes a guide rod 27, a hydraulic rod 26, a transmission device 29, two support frames 28 and two pulleys 30; the side wall of one of the support frames 28 is fixedly connected to the outer wall of the right mold 24, the support frame 28 is fixedly connected to the end of the hydraulic rod 26, the transmission device 29 connects the two support frames 28, and the bottom of the two support frames 28 is provided with a pulley 30, and the pulley 30 moves along the guide rod 27; the outer bottom of the left mold 23 is fixedly connected to the guide rod 27 ; Transmission device 2 is hydraulically driven, with an external motor, and the motor drives The left mold 23 and the right mold 24 are closed .

[0036] The wire feeding device includes an induction heating coil 16 for heating the wire and a stop valve 17 ; the stop valve 17 is used to control the amount of wire fed into the feeding spoon 6 .

[0037] The transmission device 1 includes a baffle plate 3, a first transmission rod 4 and a second transmission rod 5; the side walls of the first transmission rod 4 near both ends are hinged to the side walls of the baffle plate 3 and the side walls of the second transmission rod 5 respectively; Transmission device 1 is a mechanical arm structure with a built-in motor. The machine drives the spoon to achieve three-dimensional movement .

[0038] The present embodiment preferably further comprises a transmission device 3 for controlling the semi-solid pulping device to move up and down, the transmission device 3 comprises a third transmission rod 10, a screw rod 9 and a fixed flange 11; the fixed flange 11 is fixedly sleeved on the graphite outlet rod 14 and is fixedly connected to the screw rod 9, and the end of the screw rod 9 is movably connected to the third transmission rod 10 ; Transmission device three is a hydraulic structure, The entire transmission device can be moved up and down along the screw rod 9 by an external motor. .

[0039] Embodiment 2: A method for preparing a nano-modified aluminum-based composite material by rheological die casting, specifically comprising the following steps:

[0040] S1: transferring the aluminum alloy melt 1 to the heat preservation molten pool 2, and controlling the temperature at the liquidus line of 20-50°C;

[0041] S2: Take the material through the material taking spoon 6 and transfer it to the heat-insulating graphite crucible 8, turn on the electromagnetic stirring coil for stirring, and feed the composite material wire at the same time. The wire temperature is heated to 10-30°C below the solid phase line. After the feeding is completed, the electromagnetic stirring is maintained for 2-5 minutes;

[0042] S3: Control the graphite outlet rod 14 of the semi-solid pulping device to be inserted into the material spoon 6, and start the inert gas blowing for 3-10 seconds;

[0043] S4: pouring the melt into the barrel 20, turning on ultrasonic vibration, and preheating the mold to 300-400° C.; then injecting the melt into the mold to obtain an aluminum-based composite die-casting with a uniform distribution of reinforcement phase.

[0044] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. A preparation device for rheological die casting of nano-modified aluminum-based composite materials, characterized by: The invention comprises a heat-insulating molten pool (2), a material spoon (6), a stirring device, a transmission device for controlling the movement of the material spoon (6), a semi-solid slurry making device for filling the material spoon (6) with inert gas, a wire feeding device and a die-casting device; the wire feeding device is used to feed wire into the material spoon (6), the wire feeding device comprises an induction heating coil (16) for heating the wire and a stop valve (17); the stop valve (17) is used to control the amount of wire fed into the material spoon (6), and the die-casting device is used to die-cast the composite material; The stirring device comprises a heat-insulating graphite crucible (8) and an electromagnetic stirring induction coil (7), wherein the electromagnetic stirring induction coil (7) is embedded in the heat-insulating graphite crucible (8); The end of the transmission device 1 is connected to the side wall of the material spoon (6) and is used to transfer the aluminum alloy melt (1) in the heat-insulating molten pool (2) to the heat-insulating graphite crucible (8); The semi-solid pulping device comprises an air inlet pipe (12), an air storage tank (13) and a graphite air outlet rod (14); the air inlet pipe (12) is fixedly connected to the air inlet end of the air storage tank (13), the air outlet end of the air storage tank (13) is connected to the graphite air outlet rod (14), and the air outlet end of the graphite air outlet rod (14) is located in a material spoon (6) placed in a heat-insulating graphite crucible (8); The die-casting device comprises a barrel (20), a push rod (18), a pressure head (19), a plurality of ultrasonic probes (22) and a molding device; the plurality of ultrasonic probes (22) are embedded in the side wall of the barrel (20); the end of the push rod (18) is connected to the pressure head (19); the pressure head (19) is located in the barrel (20) and is slidably connected to the inner wall of the barrel (20); a feed port (21) is provided on the side wall of the barrel (20); and the discharge end of the barrel (20) is connected to the inside of the molding device; The molding device comprises a left mold (23), a right mold (24) and a second transmission device; a cavity (25) is provided at the closed position of the left mold (23) and the right mold (24), and the cavity (25) is connected to the discharge end of the barrel (20); the second transmission device is used to control the closing of the left mold (23) and the right mold (24).

2. The preparation equipment for rheological die casting of nano-modified aluminum-based composite materials according to claim 1, characterized in that: The second transmission device comprises a guide rod (27), a hydraulic rod (26), a transmission device (29), two support frames (28) and two pulleys (30); the side wall of one of the support frames (28) is fixedly connected to the outer side wall of the right mold (24), the other support frame (28) is fixedly connected to the end of the hydraulic rod (26), the transmission device (29) connects the two support frames (28), and the bottoms of the two support frames (28) are slidably connected to the guide rod (27); the outer bottom of the left mold (23) is fixedly connected to the guide rod (27).

3. The preparation equipment for rheological die casting of nano-modified aluminum-based composite materials according to claim 1, characterized in that: The transmission device 1 comprises a baffle (3), a first transmission rod (4) and a second transmission rod (5); the side walls of the first transmission rod (4) close to both ends are respectively hinged to the side walls of the baffle (3) and the side walls of the second transmission rod (5).

4. The preparation equipment for rheological die casting of nano-modified aluminum-based composite materials according to claim 1, characterized in that: The invention also comprises a transmission device 3 for controlling the up and down movement of the semi-solid pulping device, wherein the transmission device 3 comprises a third transmission rod (10), a screw rod (9) and a fixed flange (11); the fixed flange (11) is fixedly sleeved on the graphite gas outlet rod (14) and connected to the third transmission rod (10); the end of the screw rod (9) is movably connected to the third transmission rod (10), and the fixed flange (11) is driven to move up and down by the rotation of the screw rod (9).

5. A preparation method using the device according to any one of claims 1 to 4, characterized in that: The specific steps include: S1: transferring the aluminum alloy melt (1) to a heat-insulating molten pool (2); S2: taking the material through the material taking spoon (6) and transferring it into the heat-insulating graphite crucible (8), turning on the electromagnetic stirring coil for stirring, and feeding the composite material wire at the same time, and maintaining the electromagnetic stirring for 2-5 minutes after the feeding is completed; S3: Control the graphite outlet rod (14) of the semi-solid pulping device to be inserted into the material spoon (6), and start the inert gas blowing for 3-10 seconds; S4: pouring the melt into the barrel (20), turning on ultrasonic vibration, and preheating the mold in advance; then injecting the melt into the mold to obtain an aluminum-based composite die-casting with a uniform distribution of reinforcement phases.

6. The preparation method of nano-modified aluminum-based composite material by rheological die casting according to claim 5, characterized in that: The preheating temperature of the mold in S4 is 300-400°C.

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