Anti-gravity casting device and method based on near solidus forming

Abstract

The embodiment of the invention provides an anti-gravity casting device and method based on near solidus forming, the anti-gravity casting device comprises a crucible, a heat preservation system, a hydraulic assembly, an extrusion part, a casting mold system and a liquid rising pipe, and the crucible contains molten light alloy melt; the crucible is arranged in the heat preservation system, and the heat preservation system is used for heat preservation of the crucible; the hydraulic assembly is arranged on one side of the heat preservation system. The extrusion part is blocked in the crucible and connected with the hydraulic assembly, and the hydraulic assembly controls the extrusion part to ascend and descend; the casting mold system is arranged above the crucible; and one end of the riser tube is communicated with the crucible, and the other end is communicated with the casting system. The hydraulic assembly controls the extrusion piece to ascend and descend, so that the space in the crucible can be changed, and light alloy melt enters a casting mold system through the liquid rising pipe to be subjected to anti-gravity casting.

Description

Technical Field

[0001] The present application relates to the technical field of light alloy precision casting, and in particular to a counter-gravity casting device and a casting method based on near-solidus forming. Background Art

[0002] Lightweighting can significantly improve the flight speed, flight distance and other technical indicators of aerospace equipment, and has become an important development trend of aerospace equipment. Light alloy materials have the advantages of low density, high specific strength and good mechanical properties, and are key strategic materials for aerospace equipment. With the increasing requirements for lightweighting of key structural parts of equipment, the demand for high-performance and high-precision structural parts is urgent.

[0003] In order to achieve a significant lightweight effect, the design of key structural parts of aerospace equipment is complex, with special shapes and complex and fine structures such as built-in ribs and bosses. The forming method of "pressure processing + machining" has problems such as low material utilization, long cycle, high cost and inability to form complex structural parts, so casting is still the main forming method for large and complex structural parts.

[0004] In casting forming technology, counter-gravity casting is to make the alloy melt fill, shrink and solidify under the action of the force opposite to gravity. Light alloy melt has a low density. In the traditional gravity casting process, the melt is more likely to be turbulent, entrained and wash the mold wall. Counter-gravity casting can ensure the smooth flow and filling of the melt. The chemical properties of magnesium and aluminum alloy melts are relatively active and are prone to form oxide inclusions. The density of the above inclusions is generally higher than that of the melt, so the inclusions will settle. Counter-gravity casting is more conducive to the sedimentation of inclusions. Combined with the filtration device in the casting system, the purity of the melt can be significantly improved.

[0005] However, the counter-gravity casting device in the prior art has problems such as high pouring temperature, limited height of formed structural parts, high safety risks and inability to refine the structure. Summary of the invention

[0006] The embodiments of the present application provide an anti-gravity casting device and a casting method based on near-solidus forming, which are used to solve the problems of high pouring temperature, limited height of formed structural parts, high safety risks and inability to refine the structure in the anti-gravity casting device in the prior art.

[0007] In a first aspect, an embodiment of the present application provides a counter-gravity casting device based on near-solidus forming, comprising:

[0008] Crucible, containing molten light alloy melt;

[0009] A heat preservation system, in which the crucible is arranged, and the heat preservation system is used to keep the crucible warm;

[0010] A hydraulic assembly, arranged on one side of the thermal insulation system;

[0011] An extrusion piece is disposed in the crucible, and the extrusion piece is connected to a hydraulic assembly, and the hydraulic assembly controls the lifting and lowering of the extrusion piece to change the space in the crucible;

[0012] A casting system, which is arranged above the crucible;

[0013] A riser pipe, one end of which is connected to the crucible, and the other end of which is connected to the casting system. The light alloy melt enters the casting system through the riser pipe.

[0014] In a feasible implementation, the extrusion piece is configured in an M shape, the first end of the extrusion piece is connected to the hydraulic assembly, the second end of the extrusion piece is provided with an extrusion punch, and the extrusion punch is cooperatively connected to the crucible.

[0015] In a feasible implementation, the anti-gravity casting device also includes a data collector and a central controller. The data collector is arranged at the third end of the extrusion piece. The data collector is electrically connected to the central controller. The central controller is connected to the hydraulic component. The central controller controls the action of the hydraulic component.

[0016] In a feasible implementation, a through hole is provided at the second end of the extrusion piece, and the riser pipe passes through the through hole.

[0017] In a feasible implementation, the counter-gravity casting device further includes a pressure sensor, which is disposed on the extrusion punch and faces the inside of the crucible, and is electrically connected to the central controller.

[0018] In a feasible implementation, a heat-resistant sealing gasket is provided between the extrusion punch and the crucible.

[0019] In a second aspect, an embodiment of the present application provides a counter-gravity casting method based on near-solidus forming, using a counter-gravity casting device based on near-solidus forming as in the first aspect for casting, comprising:

[0020] Form a mold according to the structure of the casting and set the mold in the casting system;

[0021] Use crucibles to melt light alloy raw materials;

[0022] Transferring the crucible containing the light alloy melt to the insulation system;

[0023] The extrusion punch is arranged in the crucible, and the interior of the crucible is connected to the casting system by a riser tube;

[0024] Expel the air from the entire pouring system;

[0025] Use hydraulic components to control the descent of the extrusion punch for anti-gravity pouring;

[0026] Heat treat the casting.

[0027] In a feasible implementation, the pouring temperature range of the counter-gravity pouring is 630°C-720°C;

[0028] and / or, the pouring pressure ranges from 0.005KPa to 100KPa;

[0029] And / or, the pouring speed is 5mm / s-30mm / s.

[0030] In a feasible implementation, the insulation temperature range of the insulation system is 500°C-1000°C.

[0031] In a feasible implementation, the heat treatment includes solution treatment and aging treatment.

[0032] In the first aspect, the embodiment of the present application provides an anti-gravity casting device based on near-solidus forming, including a crucible, a heat preservation system, a hydraulic component, an extrusion, a casting system and a riser, wherein the crucible contains molten light alloy melt; the crucible is arranged in the heat preservation system, and the heat preservation system is used to keep the crucible warm; the hydraulic component is arranged on one side of the heat preservation system; the extrusion is blocked in the crucible, and the extrusion is connected to the hydraulic component, and the hydraulic component controls the lifting of the extrusion; the casting system is arranged above the crucible; one end of the riser is connected to the crucible, and the other end is connected to the casting system. The hydraulic component controls the lifting of the extrusion, thereby changing the space in the crucible, so that the light alloy melt enters the casting system through the riser for anti-gravity casting. Since the counter-gravity casting device uses hydraulic components to drive the extrusion parts, it can provide greater pressure and better stability, thereby ensuring that the light alloy solution can be counter-gravity cast in a temperature range close to the solidus line. The primary grains formed in the melt during the counter-gravity casting process will be broken into tiny secondary nuclei, which can greatly increase the nucleation rate of the aluminum alloy melt, significantly refine the alloy's microstructure, and improve the mechanical properties.

[0033] In the second aspect, an embodiment of the present application provides an anti-gravity casting method based on near-solidus forming, which is cast using an anti-gravity casting device based on near-solidus forming as described in the first aspect, and thus has all the beneficial effects of the technical solution of the anti-gravity casting device based on near-solidus forming as described in the first aspect, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings described herein are used to provide further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present application and do not constitute improper limitations on the present invention.

[0035] In the attached picture:

[0036] Figure 1 It is a structural schematic diagram of a counter-gravity casting device based on near-solidus forming provided by an embodiment of the present application;

[0037] Figure 2 It is a schematic flow chart of a counter-gravity casting method based on near-solidus forming provided by an embodiment of the present application;

[0038] 100-crucible; 200-insulation system; 300-hydraulic assembly; 400-extrusion piece; 500-casting system; 600-liquid lifting pipe; 700-data collector; 800-central controller; 900-heat-resistant sealing pad; 1000-middle partition;

[0039] 410 - first end; 420 - second end; 430 - third end; 440 - extrusion punch. DETAILED DESCRIPTION

[0040] In order to enable those skilled in the art to better understand the technical solutions in this application, the following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0041] In the description of the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, for example, two, three, etc., unless otherwise clearly and specifically defined.

[0042] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0043] Lightweighting can significantly improve the flight speed, flight distance and other technical indicators of aerospace equipment, and has become an important development trend of aerospace equipment. Light alloy materials have the advantages of low density, high specific strength and good mechanical properties, and are key strategic materials for aerospace equipment. With the increasing requirements for lightweighting of key structural parts of equipment, the demand for high-performance and high-precision structural parts is urgent.

[0044] In order to achieve a significant lightweight effect, the design of key structural parts of aerospace equipment is complex, with special shapes and complex and fine structures such as built-in ribs and bosses. The forming method of "pressure processing + machining" has problems such as low material utilization, long cycle, high cost and inability to form complex structural parts, so casting is still the main forming method for large and complex structural parts.

[0045] In casting forming technology, counter-gravity casting is to make the alloy melt fill, shrink and solidify under the action of the force opposite to gravity. Light alloy melt has a low density. In the traditional gravity casting process, the melt is more likely to be turbulent, entrained and wash the mold wall. Counter-gravity casting can ensure the smooth flow and filling of the melt. The chemical properties of magnesium and aluminum alloy melts are relatively active and are prone to form oxide inclusions. The density of the above inclusions is generally higher than that of the melt, so the inclusions will settle. Counter-gravity casting is more conducive to the sedimentation of inclusions. Combined with the filtration device in the casting system, the purity of the melt can be significantly improved.

[0046] However, the anti-gravity casting device in the prior art still has the following problems:

[0047] (1) High pouring temperature. Since anti-gravity casting requires the melt to overcome gravity flow, in order to maintain good fluidity, the pouring temperature of magnesium and aluminum alloy melts is relatively high. The higher the pouring temperature, the more serious the melt oxidation. In particular, the gas generated by the thermal decomposition of the resin sand mold is easy to react with the melt to form secondary oxidation inclusions, which reduces the internal and external quality of the structural parts.

[0048] (2) The height of the formed structural parts is limited. Anti-gravity casting uses gas to apply pressure. As the size of the structural parts increases, the filling pressure continues to decrease, and the internal density of the structural parts continues to decrease, so the height of the structural parts that can be formed is limited.

[0049] (3) High safety risk. On the one hand, the anti-gravity casting process uses gas to apply pressure, which requires a tank to store gas, increasing safety risks. On the other hand, light alloys are highly active. When compressed air is used, light alloys easily react with oxygen in the air to form oxide inclusions. In particular, magnesium alloys are prone to combustion when encountering oxygen during casting.

[0050] (4) Unable to refine the structure. The temperature field control in the casting mold is mainly to control the solidification sequence and reduce loose defects, but it is unable to control the microstructure.

[0051] In order to solve the problems of high pouring temperature, limited height of formed structural parts, high safety risks and inability to refine the structure in the anti-gravity casting device in the prior art, the embodiment of the present application provides an anti-gravity casting device and casting method based on near-solidus forming. The scheme provided in the embodiment of the present application will be described in detail below in conjunction with the drawings in the specification.

[0052] Figure 1 It is a schematic structural diagram of a counter-gravity casting device based on near-solidus forming provided in one embodiment of the present application.

[0053] Reference Figure 1 As shown, in the first aspect, an embodiment of the present application provides a counter-gravity casting device based on near-solidus forming, including a crucible 100 , a heat preservation system 200 , a hydraulic assembly 300 , an extrusion piece 400 , a casting system 500 and a riser 600 .

[0054] The crucible 100 contains molten light alloy liquid; the crucible 100 is arranged in the heat preservation system 200, and the heat preservation system 200 is used to keep the crucible 100 warm; the hydraulic assembly 300 is arranged on one side of the heat preservation system 200; the extrusion piece 400 is blocked in the crucible 100, and the extrusion piece 400 is connected to the hydraulic assembly 300, and the hydraulic assembly 300 controls the extrusion piece 400 to rise and fall; the casting system 500 is arranged above the crucible 100; one end of the riser 600 is connected to the crucible 100, and the other end is connected to the casting system 500. The hydraulic assembly 300 controls the extrusion piece 400 to rise and fall, thereby changing the space in the crucible 100, so that the light alloy liquid enters the casting system 500 through the riser 600, and performs anti-gravity casting.

[0055] Since the counter-gravity casting device utilizes the hydraulic component 300 to drive the extrusion part 400, it can provide greater pressure and better stability, thereby ensuring that the light alloy melt can be counter-gravity cast in a temperature range close to the solidus line. The primary grains formed in the melt during the counter-gravity casting process will be broken into tiny secondary nuclei, which can greatly increase the nucleation rate of the aluminum alloy melt, significantly refine the microstructure of the alloy, and improve the mechanical properties.

[0056] In addition, the use of hydraulic assembly 300 instead of applying pressure in gas form can not only apply greater pressure, but also output a stable pressure, thereby improving the pressure effect while achieving safe production. When a metal mold is used, due to the fast heat conduction of the metal mold, the solidification rate can be accelerated, the structure can be refined, and the mechanical properties of the alloy can be improved. The surface quality of the metal mold is relatively high, which can significantly improve the surface quality of the casting. Due to the fast solidification rate and fine structure, lower temperatures and shorter times can be used in the subsequent solution treatment process, which can reduce the tendency of grain growth and is conducive to the preparation of castings with better mechanical properties.

[0057] In order to prevent oxidation during the pouring of the light alloy melt, the anti-gravity casting device in the present application is disposed in a closed space, such as a soil pit, which is filled with protective gas. In some examples, a middle partition 1000 is used to separate the crucible 100 from the casting system 500.

[0058] Continue to refer to Figure 1 As shown, in some examples, in order to facilitate the hydraulic assembly 300 to drive the extrusion piece 400 to compress the internal space of the crucible 100, the extrusion piece 400 is configured in an M shape, the first end 410 of the extrusion piece 400 is connected to the hydraulic assembly 300, and the second end 420 of the extrusion piece 400 is provided with an extrusion punch 440, which is cooperatively connected to the crucible 100. It can be understood that when the extrusion piece 400 compresses the internal space of the crucible 100, the light alloy melt in the crucible 100 flows upward along the riser 600 to the casting system 500.

[0059] like Figure 1 As shown, in some examples, the second end 420 of the extrusion piece 400 is provided with a through hole, and the riser tube 600 is passed through the through hole.

[0060] In order to ensure the sealing effect between the extrusion punch 440 and the crucible 100 and ensure that the light alloy melt flows smoothly into the casting system 500 , a heat-resistant sealing gasket 900 is provided between the extrusion punch 440 and the crucible 100 .

[0061] The anti-gravity casting device also includes a pressure sensor, a data collector 700 and a central controller 800. The pressure sensor is arranged on the extrusion punch 440 and faces the inside of the crucible 100 to detect the pressure of the light alloy melt in the crucible 100. The pressure sensor is electrically connected to the central controller 800, and the pressure data detected by the pressure sensor is transmitted to the central controller 800. The central controller 800 determines the pressure situation in the crucible 100 through the data and controls the action of the hydraulic assembly 300 in real time to accurately control the movement of the extrusion punch 440.

[0062] The data collector 700 is disposed at the third end 430 of the extrusion member 400. The data collector 700 is electrically connected to the central controller 800. The central controller 800 is connected to the hydraulic component 300. The central controller 800 can collect the action data of the hydraulic component 300 through the data collector 700 and control the action of the hydraulic component 300 in real time according to the data.

[0063] Figure 2 It is a schematic flow chart of a counter-gravity casting method based on near-solidus forming provided in one embodiment of the present application.

[0064] Reference Figure 2As shown, in a second aspect, an embodiment of the present application provides a counter-gravity casting method based on near-solidus forming, using a counter-gravity casting device based on near-solidus forming as in the first aspect for casting, comprising:

[0065] S100: forming a mold according to the structure of the casting, and setting the mold in a casting system.

[0066] For example, a corresponding casting mold is prepared according to the structure of the casting, which can be a sand mold, a ceramic casting mold or a metal casting mold. The surface quality of the metal casting mold is higher, which can significantly improve the surface quality of the casting.

[0067] S200: Use a crucible to melt light alloy raw materials.

[0068] Light alloy raw materials such as pure metals and master alloys are placed in a crucible and heated to melt. After being subjected to a complex treatment such as stirring and refining, they are left to stand before being poured into the casting system.

[0069] S300: Transfer the crucible containing the light alloy melt to the insulation system.

[0070] The insulation system of the anti-gravity casting device in the enclosed space is turned on to keep the temperature in the insulation system within a specified temperature range, and then the crucible containing the light alloy melt is transferred to the insulation system. Exemplarily, the crucible containing the light alloy melt can be directly transported to the insulation system in the anti-gravity casting device through a conveyor track. The heating temperature range is 500°C to 1000°C, and more preferably 600°C to 680°C.

[0071] S400: The extrusion punch is arranged in the crucible, and the interior of the crucible is connected to the casting system using a riser tube.

[0072] After the melt is transferred, the extrusion punch is arranged in the crucible. First, a middle partition is placed above the crucible, and then the riser pipe is successively passed through the middle partition and the cylindrical through hole of the extrusion punch and extended into the crucible. Finally, a casting system is arranged above the middle partition, and the gate of the casting system is connected to the riser pipe.

[0073] S500: Exhaust the air in the entire pouring system.

[0074] The space of the counter-gravity casting device is filled with protective gas to exhaust air and prevent the air from oxidizing the light alloy melt during the casting process. For example, the exhaust time is 5 minutes to 30 minutes, and the gas flow rate is 10L / min to 30L / min; more preferably, the exhaust time is 10 minutes to 15 minutes, and the gas flow rate is 15 minutes to 20L / min.

[0075] S600: Use hydraulic components to control the descent of the extrusion punch for counter-gravity pouring.

[0076] Exemplarily, the pouring temperature ranges from 630°C to 720°C, the pouring pressure ranges from 0.005MPa to 100MPa, and the pouring speed ranges from 5mm / s to 30mm / s; more preferably, the pouring temperature ranges from 640°C to 680°C, the pouring pressure ranges from 0.01MPa to 50MPa, and the pouring speed ranges from 6mm / s to 15mm / s.

[0077] S700: Heat treatment of castings.

[0078] Specifically, the heat treatment includes solution treatment and aging treatment. Among them, the solution temperature is 5°C to 50°C lower than the conventional solution treatment temperature, and more preferably, the solution temperature is 10°C to 15°C lower than the conventional solution treatment temperature, and the solution time is 1h to 5h less than the conventional solution treatment time, and more preferably, the solution time is 2h to 4h less than the conventional solution treatment time.

[0079] In order to better illustrate the solutions of the application embodiments, three specific embodiments are provided below.

[0080] Example 1 VW63Z magnesium alloy sand casting

[0081] 1) Modeling: Use resin sand outer mold and clay sand core, and set them in the casting system for standby after assembly.

[0082] 2) Melting: Pure magnesium, Mg-Gd, Mg-Y and Mg-Zr master alloys are added into a crucible and heated to melt, and then subjected to composite treatments such as stirring and refining, and then allowed to stand, waiting for pouring.

[0083] 3) Heating the insulation system: The insulation system in the counter-gravity casting device is heated to a temperature of 630°C.

[0084] 4) Melt transfer: The crucible containing the melt is directly transported to the insulation system in the counter-gravity casting device through the conveyor track.

[0085] 5) Raise the extrusion punch. The central controller controls the hydraulic assembly to move the extrusion punch and raise the extrusion punch to the highest position.

[0086] 6) Place the middle baffle and the riser. After the crucible is transferred to the insulation system. After the melt is transferred, the extrusion punch is set in the crucible. First, the middle baffle is placed above the crucible, and then the riser is inserted into the crucible through the middle baffle and the cylindrical through hole of the extrusion punch. Finally, the casting system is placed above the middle baffle, and the gate of the casting system is connected to the riser.

[0087] 7) Place the mold. Place the mold on the upper part of the middle partition, making sure the gate is aligned with the riser.

[0088] 8) Exhaust. Open the gas system, introduce protective gas into the casting system, exhaust the air in the entire casting system, and place the entire counter-gravity casting device in a protective gas environment. The exhaust time is 15 minutes.

[0089] 9) Counter-gravity pouring. The central control device is used to control the hydraulic assembly to move downward, and the extrusion punch is controlled to press the melt to fill the mold in counter-gravity. The pouring temperature is 650°C, the pouring pressure is 40KPa, and the pouring speed is 10mm / s.

[0090] 10) Post-processing of castings. After removing the mold, cutting the gating system, and grinding, the casting is ready for heat treatment.

[0091] 11) Heat treatment. The castings were subjected to solution treatment and aging treatment in sequence, with the solution temperature at 480°C for 15 hours and the aging temperature at 220°C for 30 hours.

[0092] Example 2 VW63Z magnesium alloy metal mold casting

[0093] 1) Modeling: Use metal casting molds, which are assembled and set in the casting system for standby use.

[0094] 2) Melting: Pure magnesium, Mg-Gd, Mg-Y and Mg-Zr master alloys are added into a crucible and heated to melt, and then subjected to composite treatments such as stirring and refining, and then allowed to stand, waiting for pouring.

[0095] 3) Heating the insulation system: The insulation system in the counter-gravity casting device is heated to a temperature of 630°C.

[0096] 4) Melt transfer: The crucible containing the melt is directly transported to the insulation system in the counter-gravity casting device through the conveyor track.

[0097] 5) Raise the extrusion punch. The central controller controls the hydraulic assembly to move the extrusion punch and raise the extrusion punch to the highest position.

[0098] 6) Place the middle baffle and the riser. After the crucible is transferred to the insulation system. After the melt is transferred, the extrusion punch is set in the crucible. First, the middle baffle is placed above the crucible, and then the riser is inserted into the crucible through the middle baffle and the cylindrical through hole of the extrusion punch. Finally, the casting system is placed above the middle baffle, and the gate of the casting system is connected to the riser.

[0099] 7) Place the mold. Place the mold on the upper part of the middle partition, making sure the gate is aligned with the riser.

[0100] 8) Exhaust. Open the gas system, introduce protective gas into the casting system, exhaust the air in the entire casting system, and place the entire counter-gravity casting device in a protective gas environment. The exhaust time is 10 minutes.

[0101] 9) Counter-gravity pouring. The central control device is used to control the hydraulic assembly to move downward, and the extrusion punch is controlled to press the melt to fill the mold in counter-gravity. The pouring temperature is 630°C, the pouring pressure is 60KPa, and the pouring speed is 8mm / s.

[0102] 10) Post-processing of castings. After removing the mold, cutting the gating system, and grinding, the casting is ready for heat treatment.

[0103] 11) Heat treatment. The castings were subjected to solution treatment and aging treatment in sequence, with the solution temperature being 450°C for 8 hours and the aging temperature being 220°C for 30 hours.

[0104] Example 3 - ZL114A aluminum alloy metal mold casting

[0105] 1) Modeling: Use metal casting molds, which are assembled and set in the casting system for standby use.

[0106] 2) Melting: Add raw materials such as pure aluminum, pure silicon, and pure magnesium into a crucible and heat and melt them. After a complex treatment such as stirring and refining, they are left to stand and wait for pouring.

[0107] 3) Heating the insulation system: The insulation system in the counter-gravity casting device is heated to a temperature of 600°C.

[0108] 4) Melt transfer: The crucible containing the melt is directly transported to the insulation system in the counter-gravity casting device through the conveyor track.

[0109] 5) Raise the extrusion punch. The central controller controls the hydraulic assembly to move the extrusion punch and raise the extrusion punch to the highest position.

[0110] 6) Place the middle baffle and the riser. After the crucible is transferred to the insulation system. After the melt is transferred, the extrusion punch is set in the crucible. First, the middle baffle is placed above the crucible, and then the riser is inserted into the crucible through the middle baffle and the cylindrical through hole of the extrusion punch. Finally, the casting system is placed above the middle baffle, and the gate of the casting system is connected to the riser.

[0111] 7) Place the mold. Place the mold on the upper part of the middle partition, making sure the gate is aligned with the riser.

[0112] 8) Exhaust. Open the gas system, introduce protective gas into the casting system, exhaust the air in the entire casting system, and place the entire counter-gravity casting device in a protective gas environment. The exhaust time is 10 minutes.

[0113] 9) Counter-gravity pouring. The central control device is used to control the hydraulic assembly to move downward, and the extrusion punch is controlled to press the melt to fill the mold in counter-gravity. The pouring temperature is 640°C, the pouring pressure is 50KPa, and the pouring speed is 10mm / s.

[0114] 10) Post-processing of castings. After removing the mold, cutting the gating system, and grinding, the casting is ready for heat treatment.

[0115] 11) Heat treatment. The casting was subjected to solution treatment and aging treatment in sequence, with the solution temperature being 500°C, the solution time being 8 hours, and the aging temperature being 160°C, the time being 10 hours, and finally a ZL114A aluminum alloy casting was obtained.

[0116] According to the above Example 1 and Example 2, the prepared VW63Z rare earth magnesium alloy casting was sampled and tested for room temperature mechanical properties. The results are shown in Table 1.

[0117] Table 1 Mechanical properties test of casting body at room temperature

[0118]

[0119] It can be seen from the comparison in the above table that the castings cast by the technical solution of this application have better mechanical properties.

[0120] It is easy to understand that those skilled in the art can combine, split, reorganize, etc. the embodiments of the present application to obtain other embodiments based on the several embodiments provided in the present application, and these embodiments do not exceed the protection scope of the present application.

[0121] The above specific implementation methods further explain in detail the purpose, technical solutions and beneficial effects of the embodiments of the present application. It should be understood that the above are only specific implementation methods of the embodiments of the present application and are not used to limit the protection scope of the embodiments of the present application. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the embodiments of the present application should be included in the protection scope of the embodiments of the present application.

Claims

1. A counter-gravity casting device based on near-solidus forming, characterized in that: include: Crucible, containing molten light alloy melt; A heat preservation system, wherein the crucible is arranged in the heat preservation system, and the heat preservation system is used to keep the crucible warm; A hydraulic assembly, arranged on one side of the thermal insulation system; An extrusion piece is disposed in the crucible, the extrusion piece is connected to the hydraulic assembly, and the hydraulic assembly controls the lifting and lowering of the extrusion piece to change the space in the crucible; A casting system, arranged above the crucible; A riser tube, one end of which is connected to the crucible, and the other end of which is connected to the casting system, and the light alloy melt enters the casting system through the riser tube.

2. The anti-gravity casting device based on near-solidus forming according to claim 1 is characterized in that: The extrusion piece is configured in an M shape, a first end of the extrusion piece is connected to the hydraulic assembly, and a second end of the extrusion piece is provided with an extrusion punch, and the extrusion punch is cooperatively connected to the crucible.

3. The anti-gravity casting device based on near-solidus forming according to claim 2 is characterized in that: The anti-gravity casting device also includes a data collector and a central controller. The data collector is arranged at the third end of the extrusion piece. The data collector is electrically connected to the central controller. The central controller is connected to the hydraulic component. The central controller controls the action of the hydraulic component.

4. The anti-gravity casting device based on near-solidus forming according to claim 1, characterized in that: A through hole is provided at the second end of the extrusion piece, and the liquid riser is passed through the through hole.

5. The anti-gravity casting device based on near-solidus forming according to claim 3 is characterized in that: The counter-gravity casting device further comprises a pressure sensor, which is disposed on the extrusion punch and faces the interior of the crucible, and is electrically connected to the central controller.

6. The anti-gravity casting device based on near-solidus forming according to claim 2, characterized in that: A heat-resistant sealing pad is provided between the extrusion punch and the crucible.

7. A method for counter-gravity casting based on near-solidus forming, using the counter-gravity casting device based on near-solidus forming as claimed in any one of claims 1 to 6 for casting, comprising: Forming a casting mold according to the structure of the casting, and arranging the casting mold in a casting mold system; Use crucibles to melt light alloy raw materials; Transferring the crucible containing the light alloy melt to the insulation system; The extrusion punch is arranged in the crucible, and the interior of the crucible is connected with the casting system by a riser pipe; Expel the air from the entire pouring system; Use hydraulic components to control the descent of the extrusion punch for anti-gravity pouring; Heat treat the casting.

8. The counter-gravity casting method based on near-solidus forming according to claim 7, characterized in that: The pouring temperature range of the counter-gravity pouring is 630°C-720°C; and / or, the pouring pressure ranges from 0.005KPa to 100KPa; And / or, the pouring speed is 5mm / s-30mm / s.

9. The counter-gravity casting method based on near-solidus forming according to claim 7, characterized in that: The insulation temperature range of the insulation system is 500°C-1000°C.

10. The counter-gravity casting method based on near-solidus forming according to claim 7, characterized in that: The heat treatment includes solution treatment and aging treatment.

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