Semi-solid die-casting apparatus and method for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles

Abstract

This invention discloses a semi-solid die-casting apparatus and method for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles, relating to the field of metal die-casting equipment technology. It includes a multi-stage pressurization mechanism connected to an injection head; a pressure sensor is installed inside the injection head; the multi-stage pressurization mechanism includes a three-stage nested piston mechanism and an oil circuit control mechanism. By setting up a multi-stage pressurization mechanism, the invention drives the first-stage, second-stage, and third-stage pistons to slide axially along the injection cylinder, gradually increasing the slurry injection speed and pressure. The oil circuit control mechanism dynamically adjusts the piston thrust, achieving stepless and continuous pressure adjustment and improving the slurry filling effect. By setting up a slurry rheology control mechanism, slurry stirring and injection are integrated, using the thrust of the injection piston to replace the traditional delivery pump, ensuring the slurry remains in a closed environment from preparation to injection, simultaneously completing solid particle refinement, solid fraction control, and high-pressure filling.

Description

Technical Field

[0001] This invention relates to the field of metal die-casting equipment technology, and in particular to a semi-solid die-casting equipment and method for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles. Background Technology

[0002] In the field of aluminum alloy profile forming, semi-solid die casting technology has become an important process for manufacturing ultra-thin-walled, high-strength structural components due to its advantages in improving product density and mechanical properties. The rheological properties of the semi-solid metal slurry (solid-liquid coexistence state) are key to affecting the forming quality, among which the morphology of solid particles, the stability of the solid fraction, and the viscosity of the slurry play a decisive role. In traditional processes, the preparation and injection of semi-solid slurry are mostly carried out using separate equipment. That is, after the slurry is prepared by a stirring device, it is transferred to the injection mechanism of the die casting machine through a conveying pipeline, and then the injection cylinder completes the filling. However, this mode has many problems. For example, the solid particles of the slurry are prone to agglomeration during the slurry transportation process, and the viscosity fluctuates greatly. It is particularly difficult to meet the stringent requirements of slurry fluidity for ultra-thin-walled profiles with small wall thicknesses.

[0003] For example, Chinese Patent CN106424630A discloses an ultrasonic-assisted semi-solid die-casting device and method for complex thin-walled aluminum alloy parts. It includes a die-casting machine, a die-casting mold, an ultrasonic vibration system, and a cooling system. The die-casting mold is installed on the die-casting machine. An injection assembly passes through a stationary mold fixing plate and connects to the die-casting mold. The ultrasonic vibration system is installed and connected to the moving mold of the die-casting mold. The ultrasonic vibration system directly acts on the moving mold to perform ultrasonic-assisted semi-solid die-casting. The moving mold is equipped with a cooling system connected to the ultrasonic vibration system. This invention can effectively reduce the degree of solid-phase agglomeration, improve the flowability and filling capacity of semi-solid metals, refine grains, increase the density of castings, and further improve the mechanical and thermal conductivity of aluminum alloy castings, providing a new forming method for manufacturing complex thin-walled aluminum alloy castings.

[0004] Although the above-mentioned device improves the flowability and filling capacity of semi-solid metal, the following technical problems still exist: when faced with high viscosity of semi-solid metal slurry and narrow cavity and long process of ultra-thin aluminum alloy profile, the injection mechanism is difficult to provide a sufficiently high pressure that can be dynamically adjusted according to different stages of the filling process, which easily leads to defects such as air entrapment and incomplete filling, and cannot well meet the die casting requirements of ultra-thin aluminum alloy profile. Summary of the Invention

[0005] The purpose of this application is to provide a semi-solid die-casting apparatus and method for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles, which can effectively solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this application provides the following technical solution: a semi-solid die-casting device for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles, comprising a multi-stage pressurization mechanism connected to an injection head; a pressure sensor is installed inside the injection head; the multi-stage pressurization mechanism includes a three-stage nested piston mechanism and an oil circuit control mechanism; wherein, the three-stage nested piston mechanism includes an injection cylinder, a first-stage piston, a guide sleeve, a second-stage piston, and a third-stage piston; both ends of the injection cylinder are connected to the die-casting machine frame via flanges; the first-stage piston is slidably connected to the injection cylinder along its axial direction, and the guide sleeve is coaxially sleeved on the first-stage piston, with the outer wall of the guide sleeve abutting against the inner wall of the injection cylinder. The secondary piston is coaxially inserted into the primary piston; one end of the tertiary piston is coaxially inserted into the secondary piston, and the other end of the tertiary piston extends outward from the injection cylinder and is coaxially connected to the injection head; the primary piston has multiple first flow holes, the secondary piston has a second flow hole, and the tertiary piston has a third flow hole; the slurry sequentially passes through the first flow hole, the second flow hole, and the third flow hole to communicate with the injection head; one end of the oil circuit control mechanism is connected to the interior of the injection cylinder, and the other end of the oil circuit control mechanism is connected to the hydraulic pump station and is used to control the sliding of the primary piston, the secondary piston, and the tertiary piston along the axial direction of the injection cylinder.

[0007] Preferably, the first-stage piston includes a first piston rod and a first piston head; one end of the first piston rod is coaxially connected to the first piston head, and the first piston head is coaxially slidably connected to the injection cylinder body; one side of the first piston head and the injection cylinder body form a first-stage pressurization chamber.

[0008] A displacement sensor is installed between the first piston rod and the injection cylinder to detect the displacement of the first piston head.

[0009] Preferably, the secondary piston includes a second piston rod and a second piston head; one end of the second piston rod is coaxially connected to the second piston head; a first guide groove is formed in the first piston rod, and the second piston head is slidably connected to the first guide groove on the same axis; one side of the second piston head and the first guide groove form a secondary pressurization chamber.

[0010] Preferably, the second piston rod has a second guide groove, and one end of the third-stage piston and the second guide groove form a third-stage pressurization chamber.

[0011] Preferably, the oil circuit control mechanism includes a primary oil inlet pipe, a secondary oil inlet pipe, a tertiary oil inlet pipe, three solenoid directional valves, and a proportional relief valve; the primary, secondary, and tertiary oil inlet pipes are all fixed to the injection cylinder body, and each of the primary, secondary, and tertiary oil inlet pipes has a solenoid directional valve and a proportional relief valve, with the proportional relief valve located between the injection cylinder body and the solenoid directional valve;

[0012] The guide sleeve, the first piston rod, the first piston head, and the inner wall of the injection cylinder form a primary hydraulic chamber, and the primary oil inlet pipe is connected to the primary hydraulic chamber. An isolation ring is fixed on the third-stage piston, and the outer wall of the isolation ring abuts against the inner wall of the injection cylinder. The isolation ring, the third-stage piston, the second piston rod, the second piston head, the inner wall of the first piston rod, the guide sleeve, and the inner wall of the injection cylinder form a secondary hydraulic chamber, and the secondary oil inlet pipe is connected to the secondary hydraulic chamber. The third-stage piston, the isolation ring, and the injection cylinder form a tertiary hydraulic chamber, and the tertiary oil inlet pipe is connected to the tertiary hydraulic chamber.

[0013] Preferably, the injection cylinder body has a slurry inlet at one end near the first-stage piston; the slurry inlet is equipped with a slurry rheology control mechanism; the slurry rheology control mechanism includes a twin-screw stirring mechanism and a spiral control mechanism; the twin-screw stirring mechanism is connected to the injection cylinder body through the spiral control mechanism; the twin-screw stirring mechanism is used to stir the slurry raw materials; the spiral control mechanism is used to deliver the slurry into the injection cylinder body.

[0014] Preferably, the twin-screw mixing mechanism includes a mixing shell, a driving component, a feed hopper, and a pair of mixing screws; the pair of mixing screws are rotatably connected to the mixing shell around their axis, the driving component is installed on the mixing shell, and the output end of the driving component is connected to the pair of mixing screws; a feed hopper is provided on the side of the mixing shell near the driving component, and is used to introduce aluminum alloy raw material particles into the mixing shell.

[0015] Preferably, the spiral control mechanism includes a conical shell, a spiral pusher head, a floating isolation seat, and a motor; one end of the conical shell is connected to the injection cylinder, and the other end of the conical shell is connected to the stirring shell; the spiral pusher head is coaxially disposed inside the conical shell; the spiral pusher head is a conical structure adapted to the inner wall of the conical shell, and the pitch of the spiral pusher head gradually decreases from the feed end to the discharge end; a floating isolation seat is installed on the first piston head, the motor is fixed to the floating isolation seat, and the output end of the motor is coaxially connected to the spiral pusher head; a check valve is provided inside the stirring shell near the injection cylinder;

[0016] The spiral control mechanism also includes a guide tube; one end of the guide tube is fixed to the first piston head, the guide tube is slidably connected to the injection cylinder along its axis, and the motor wire is inserted into the guide tube.

[0017] Preferably, the slurry rheology control mechanism further includes a temperature control mechanism, which includes a pair of temperature controllers disposed on the mixing shell and a temperature controller disposed on the conical shell; the temperature of the slurry inside the mixing shell and the conical shell is controlled by the temperature controllers.

[0018] A semi-solid die-casting method for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles, including the aforementioned semi-solid die-casting apparatus for such profiles, specifically includes the following steps:

[0019] Step 1, Three-Stage Propulsion: First, the first-stage, second-stage, and third-stage pistons are all fully retracted. The oil supply is controlled by the hydraulic control mechanism, pushing the first-stage piston forward to allow the slurry to enter the flow channel, completing the first-stage propulsion. Then, the oil inlet is controlled by the hydraulic control mechanism, driving the second-stage piston forward to move synchronously with the first-stage piston, achieving second-stage relay. Finally, the oil inlet is controlled by the hydraulic control mechanism, driving the third-stage piston forward to complete the final filling, achieving the three-stage sprint.

[0020] Step 2, Return Reset: After filling is completed, the oil circuit control mechanism controls the return oil, causing the third-stage piston to retract first, followed by the second-stage piston, and finally the last-stage piston, until all three retract to their initial positions.

[0021] In summary, the technical effects and advantages of this invention are as follows:

[0022] The present invention has a reasonable structure. By setting up a multi-stage pressurization mechanism, the first-stage piston, the second-stage piston and the third-stage piston are driven to slide along the axial direction of the injection cylinder, so as to gradually increase the injection speed and pressure of the slurry. The piston thrust is dynamically adjusted by the oil circuit control mechanism to achieve stepless and continuous adjustment of the pressure, thereby improving the slurry filling effect.

[0023] In this invention, by setting up a slurry rheology control mechanism, slurry mixing and injection are combined. By adopting a coaxial nesting and time-sequential linkage design, the slurry preparation function of the twin screw is embedded into the front flow channel of the injection mechanism. The thrust of the injection piston is used to replace the traditional delivery pump, so that the slurry is always in a closed environment from preparation to injection. The solid phase particle refinement, solid phase ratio regulation and high pressure filling are completed simultaneously, eliminating the problems of slurry delivery delay and performance degradation in traditional split equipment.

[0024] By setting up a spiral control mechanism, the motor is driven by a first-stage piston, enabling the spiral propulsion head to achieve a combination of rotation and linear motion. The precise shaft system design ensures stable motion and power transmission. During the mixing stage, the reverse meshing shearing of the spiral propulsion head and the twin screws, as well as segmented temperature control, are used to achieve slurry homogenization. During the discharge stage into the first pressurization chamber, the qualified slurry is efficiently introduced into the first pressurization chamber through forward pushing, check valve avoidance design, and pre-compression, laying the foundation for subsequent injection molding. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the overall three-dimensional structure of the present invention;

[0027] Figure 2 This is a three-dimensional enlarged structural schematic diagram of the multi-stage booster mechanism of the present invention;

[0028] Figure 3 This is a partially cross-sectional, three-dimensional enlarged structural diagram of the injection cylinder body of the present invention;

[0029] Figure 4 This is a partially cross-sectional, magnified three-dimensional structural diagram of the three-stage nested piston mechanism of the present invention.

[0030] Figure 5 This is a front view enlarged structural diagram of the three-level nested piston mechanism of the present invention;

[0031] Figure 6 This is a schematic diagram of the overall and partial cross-section of the present invention from a first-view perspective.

[0032] Figure 7 This is a schematic diagram of the overall and partial cross-section of the three-dimensional structure from a second perspective of the present invention;

[0033] Figure 8 For the present invention Figure 7 Enlarged structural diagram of region A in the middle;

[0034] Figure 9 This is a detailed three-dimensional enlarged cross-sectional view of a portion of the spiral control mechanism of the present invention;

[0035] Figure 10 This is a schematic diagram of the method flow of the present invention.

[0036] In the diagram: 1. Injection head; 2. Multi-stage pressurization mechanism; 21. Three-stage nested piston mechanism; 211. Injection cylinder; 212. First-stage piston; 2121. First piston rod; 2122. First piston head; 2123. First flow hole; 213. Guide sleeve; 214. First-stage pressurization chamber; 215. Second-stage piston; 2151. Second piston rod; 2152. Second piston head; 2153. Second flow hole; 216. Second-stage pressurization chamber; 217. Third-stage piston; 218. Third flow hole; 219. Third-stage pressurization chamber; 22. Oil circuit control mechanism; 221. First-stage oil inlet pipe; 222. First-stage... 223. Hydraulic chamber; 224. Secondary oil inlet pipe; 225. Tertiary oil inlet pipe; 226. Isolation ring; 227. Tertiary hydraulic chamber; 228. Solenoid directional valve; 229. Proportional relief valve; 3. Slurry rheology control mechanism; 31. Twin-screw stirring mechanism; 311. Stirring housing; 312. Stirring screw; 313. Drive component; 314. Feed hopper; 32. Spiral control mechanism; 321. Conical housing; 322. Spiral pusher head; 323. Floating isolation seat; 324. Motor; 325. Guide tube; 326. Check valve; 33. Temperature control mechanism; 331. Temperature controller. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] Example 1: Please refer to Figures 1-4The semi-solid die-casting device for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles shown includes a multi-stage pressurization mechanism 2 connected to an injection head 1; a pressure sensor is installed inside the injection head 1; the multi-stage pressurization mechanism 2 includes a three-stage nested piston mechanism 21 and an oil circuit control mechanism 22; wherein, the three-stage nested piston mechanism 21 includes an injection cylinder 211, a first-stage piston 212, a guide sleeve 213, a second-stage piston 215, and a third-stage piston 217; the two ends of the injection cylinder 211 are connected to the die-casting machine frame through flanges; the first-stage piston 212 is slidably connected to the injection cylinder 211 along its axial direction, the guide sleeve 213 is coaxially sleeved on the first-stage piston 212, and the outer wall of the guide sleeve 213 abuts against the inner wall of the injection cylinder 211; the second-stage piston 215 is coaxially inserted into the first-stage piston 211. 12; One end of the third-stage piston 217 is coaxially inserted into the second-stage piston 215, and the other end of the third-stage piston 217 extends outward from the injection cylinder 211 and is coaxially connected to the injection head 1; The first-stage piston 212 has multiple first flow holes 2123, the second-stage piston 215 has a second flow hole 2153, and the third-stage piston 217 has a third flow hole 218; The slurry passes through the first flow hole 2123, the second flow hole 2153, and the third flow hole 218 in sequence to communicate with the injection head 1; One end of the oil circuit control mechanism 22 is connected to the inside of the injection cylinder 211, and the other end of the oil circuit control mechanism 22 is connected to the hydraulic pump station and is used to control the sliding of the first-stage piston 212, the second-stage piston 215, and the third-stage piston 217 along the axial direction of the injection cylinder 211.

[0039] It should be noted that the injection head 1 is connected to the multi-stage pressurization mechanism 2, and the pressure sensor inside the injection head 1 can monitor the pressure during the injection process in real time. When the three-stage nested piston mechanism 21 in the multi-stage pressurization mechanism 2 is working, it drives the first-stage piston 212, the second-stage piston 215, and the third-stage piston 217 to slide axially along the injection cylinder body 211 by controlling the inlet and outlet of hydraulic oil. This allows the slurry after stirring to enter from one end of the injection cylinder body 211, first through the first flow hole 2123 on the first-stage piston 212 into the first-stage pressurization chamber 214, and then through the second-stage piston 212 into the first-stage pressurization chamber 214. The second flow hole 2153 on the plug 215 enters the secondary pressurization chamber 216, and finally flows to the injection head 1 through the third flow hole 218 on the tertiary piston 217 to realize the injection action; and the injection force is detected in real time by the pressure sensor in the injection head 1, and the data is transmitted to the PLC controller, which can then dynamically adjust the piston thrust through the oil circuit control mechanism 22 to achieve stepless continuous adjustment of the pressure; it is understood that the pressure sensor and the PLC controller are existing technologies, and the pressure sensor is a strain gauge pressure sensor, which is not shown in the figure and will not be described in detail;

[0040] The three-stage nested piston mechanism 21 enables multi-stage pressurization, and the oil circuit control mechanism 22 can dynamically adjust the pressure according to the injection process. This solves the problem of insufficient pressure and difficulty in dynamic adjustment of the injection mechanism in traditional split equipment, meeting the stringent requirements of ultra-thin-walled aluminum alloy profiles for injection pressure and reducing defects such as air entrapment and incomplete casting. Furthermore, the combined use of the first flow hole 2123, the second flow hole 2153, and the third flow hole 218 provides a stable conveying path for the slurry, reduces the flow resistance of the slurry during the conveying process, and avoids the retention or agglomeration of solid particles in the conveying path, which helps to maintain the good fluidity of the slurry.

[0041] Please see Figures 1-5 The first-stage piston 212 includes a first piston rod 2121 and a first piston head 2122; one end of the first piston rod 2121 is coaxially connected to the first piston head 2122, and the first piston head 2122 is coaxially slidably connected within the injection cylinder 211; one side of the first piston head 2122 and the injection cylinder 211 form a first-stage pressurization chamber 214; a displacement sensor is provided between the first piston rod 2121 and the injection cylinder 211 to detect the displacement of the first piston head 2122; the second-stage piston 2... 15 includes a second piston rod 2151 and a second piston head 2152; one end of the second piston rod 2151 is coaxially connected to the second piston head 2152; a first guide groove is provided in the first piston rod 2121, and the second piston head 2152 is slidably connected to the first guide groove on the same axis; one side of the second piston head 2152 and the first guide groove form a secondary pressurization chamber 216; a second guide groove is provided on the second piston rod 2151, and one end of the third-stage piston 217 and the second guide groove form a third-stage pressurization chamber 219.

[0042] It should be noted that during operation, after the slurry enters the primary pressurizing chamber 214, the pressure inside the primary pressurizing chamber 214 increases as the primary piston 212 advances, pushing the slurry at a slower speed through the first flow hole 2123 into the secondary pressurizing chamber 216. Using lower pressure and speed is to avoid turbulence caused by excessive speed in the initial filling stage, thereby reducing air entrapment. When the slurry enters the cavity initially, approximately 50% full, the secondary piston 215 begins to work, further increasing the pressure and speed. At this point, the filling difficulty of the cavity gradually increases, requiring greater pressure to propel the slurry to continue flowing. At this time, the primary piston 212 and the secondary piston 215 move synchronously, their combined thrust overcoming the gradually increasing flow resistance of the cavity, ensuring continuous slurry filling. In the final stage of filling, i.e., the last 30% of the cavity is filled, the tertiary piston 217 is activated, further increasing the pressure and speed. This is because the far end area of ​​the ultra-thin-walled profile is the most difficult to fill, requiring extremely high pressure and speed to ensure that the slurry fills the area before solidification. Therefore, the design of a multi-stage pressurization chamber allows the slurry pressure to be gradually increased, providing appropriate pressure according to different stages of the ultra-thin-walled aluminum alloy profile filling process, thereby improving the slurry's filling capacity. During the working stage of the third-stage piston 217, the injection force is collected in real time by a pressure sensor. If the pressure exceeds the preset threshold, the controller will reduce the oil supply pressure through the oil circuit control mechanism 22 to avoid mold overload. If the pressure is insufficient, the oil supply pressure will be increased to ensure sufficient filling. After filling is completed, the oil circuit control mechanism 22 switches the control of the return oil in the order of the third-stage piston 217, the second-stage piston 215, and the first-stage piston 212. The hydraulic oil flows back to the oil tank through the return oil circuit, causing the third-stage piston 217, the second-stage piston 215, and the first-stage piston 212 to return to their initial positions, ready for the next die-casting cycle.

[0043] It should be noted that the diameter of the first piston head 2122 is larger than that of the second piston head 2152, and the diameter of the second piston head 2152 is larger than that of the third-stage piston 217. Therefore, under the same oil supply pressure, the injection specific pressure is amplified, and the speed can be increased.

[0044] During operation, the displacement sensor monitors the sliding distance of the first piston head 2122 within the injection cylinder 211 in real time and transmits the displacement signal to the control system. The control system determines the motion state of the first-stage piston 212 based on the displacement data and then adjusts the oil supply through the oil circuit control mechanism 22 to ensure that the first-stage piston 212 moves along a preset trajectory. The displacement sensor accurately determines the position of the first-stage piston 212, providing data support for the coordinated movement of each piston, ensuring the accuracy of the injection process, and reducing filling defects caused by piston movement deviations. It is understood that both the displacement sensor and the control system are existing technologies. The control system is a PLC control system, which is not shown in the figure and will not be described in detail.

[0045] Please see Figures 1-5 The oil circuit control mechanism 22 includes a primary oil inlet pipe 221, a secondary oil inlet pipe 223, a tertiary oil inlet pipe 225, three solenoid directional valves 228, and a proportional relief valve 229. The primary oil inlet pipe 221, secondary oil inlet pipe 223, and tertiary oil inlet pipe 225 are all fixed to the injection cylinder body 211. Each of the primary oil inlet pipe 221, secondary oil inlet pipe 223, and tertiary oil inlet pipe 225 has a solenoid directional valve 228 and a proportional relief valve 229, with the proportional relief valve 229 positioned between the injection cylinder body 211 and the solenoid directional valves 228. The guide sleeve 213, the first piston rod 2121, the first piston head 2122, and the inner wall of the injection cylinder body 211 are also included. A first-stage hydraulic chamber 222 is formed, and a first-stage oil inlet pipe 221 is connected to the first-stage hydraulic chamber 222. An isolation ring 226 is fixed on the third-stage piston 217. The outer wall of the isolation ring 226 abuts against the inner wall of the injection cylinder 211. The isolation ring 226, the third-stage piston 217, the second piston rod 2151, the second piston head 2152, the inner wall of the first piston rod 2121, the guide sleeve 213, and the inner wall of the injection cylinder 211 form a second-stage hydraulic chamber 224. The second-stage oil inlet pipe 223 is connected to the second-stage hydraulic chamber 224. The third-stage piston 217, the isolation ring 226, and the injection cylinder 211 form a third-stage hydraulic chamber 227. The third-stage oil inlet pipe 225 is connected to the third-stage hydraulic chamber 227.

[0046] It should be noted that the on / off state of each oil inlet pipe is controlled by the electromagnetic reversing valve 228. Hydraulic oil enters the first-stage oil pressure chamber 222 through the first-stage oil inlet pipe 221, driving the first-stage piston 212. It enters the second-stage oil pressure chamber 224 through the second-stage oil inlet pipe 223, driving the second-stage piston 215. It enters the third-stage oil pressure chamber 227 through the third-stage oil inlet pipe 225, driving the third-stage piston 217. The proportional relief valve 229 regulates the oil pressure in each oil pressure chamber. The independent oil circuit control allows the movement of the first-stage piston 212, the second-stage piston 215, and the third-stage piston 217 to be individually controlled. The pressure adjustment is flexible and can be changed in real time according to different needs of the filling process, ensuring the stability of the injection process and improving the product molding quality.

[0047] Please see Figure 1 and Figure 6 The injection cylinder 211 has a slurry inlet at one end near the first-stage piston 212. The slurry inlet is equipped with a slurry rheology control mechanism 3. The slurry rheology control mechanism 3 includes a twin-screw stirring mechanism 31 and a screw control mechanism 32. The twin-screw stirring mechanism 31 is connected to the injection cylinder 211 through the screw control mechanism 32. The twin-screw stirring mechanism 31 is used to stir the slurry raw materials. The screw control mechanism 32 is used to deliver the slurry into the injection cylinder 211.

[0048] It should be noted that the twin-screw stirring mechanism 31 stirs the aluminum alloy raw material to form a semi-solid slurry, and the screw control mechanism 32 stably delivers the stirred slurry into the injection cylinder 211; the slurry rheology control mechanism 3 realizes the integration of slurry preparation and transportation, reduces the performance fluctuation of the slurry during the transportation process, ensures the stability of the solid fraction, and helps to meet the stringent requirements of ultra-thin-walled aluminum alloy profiles for slurry flowability.

[0049] Please see Figures 6-7 It is understood that this application does not limit the specific structure and installation method of the twin-screw mixing mechanism 31. The following only provides a feasible technical solution: The twin-screw mixing mechanism 31 includes a mixing shell 311, a driving member 313, a feed hopper 314, and a pair of mixing screws 312; the pair of mixing screws 312 are rotatably connected to the mixing shell 311 around their axis, the driving member 313 is installed on the mixing shell 311, and the output end of the driving member 313 is connected to the pair of mixing screws 312; a feed hopper 314 is provided on the side of the mixing shell 311 near the driving member 313, and is used to introduce aluminum alloy raw material particles into the mixing shell 311.

[0050] It should be noted that aluminum alloy raw material particles enter the mixing shell 311 from the feed hopper 314. The drive component 313 drives a pair of stirring screws 312 to rotate. The stirring screws 312 shear and mix the raw material, making it a semi-solid slurry with uniform solid particle distribution. The twin-screw mixing can effectively refine the solid particles, reduce particle agglomeration, improve the uniformity of the slurry, and provide a high-quality slurry for subsequent die casting.

[0051] Please see Figures 6-9 The spiral control mechanism 32 includes a conical shell 321, a spiral pusher head 322, a floating isolation seat 323, and a motor 324. One end of the conical shell 321 is connected to the injection cylinder 211, and the other end is connected to the stirring shell 311. The spiral pusher head 322 is coaxially arranged inside the conical shell 321. The spiral pusher head 322 has a conical structure adapted to the inner wall of the conical shell 321, and the pitch of the spiral pusher head 322 gradually decreases from the feed end to the discharge end. The first piston head 2122... A floating isolation seat 323 is installed on the upper part, and a motor 324 is fixedly mounted on the floating isolation seat 323. The output end of the motor 324 is coaxially connected to the spiral push head 322. A check valve 326 is provided in the stirring shell 311 near the injection cylinder 211. The spiral control mechanism 32 also includes a guide tube 325. One end of the guide tube 325 is fixed to the first piston head 2122, and the guide tube 325 is slidably connected to the injection cylinder 211 along its axis. The wire of the motor 324 is inserted into the guide tube 325.

[0052] It should be noted that the motor 324 drives the spiral pusher head 322 to rotate inside the conical housing 321. The stirred slurry is conveyed to the injection cylinder 211 under the action of the spiral pusher head 322. The pitch gradually decreases, so that the slurry is gradually compressed. The conical structure and variable pitch design enhance the pushing force and compression effect of the slurry, and the check valve 326 prevents the slurry from flowing back. Meanwhile, the guide tube 325 moves with the first piston head 2122 and protects the motor 324 wires, ensuring the safety of the motor wires during the piston movement and improving the stability of the slurry delivery.

[0053] It should be noted that the taper of the spiral propulsion head 322 is 5°-10°, and the gap between its conical surface and the conical shell 321 is 0.1-0.3mm, gradually increasing from the front end to the rear end along the axial direction. The front end ensures sealing during injection, while the rear end is slightly larger to avoid motion interference. This gap is much smaller than the diameter of the solid particles in the slurry, which can prevent particle jamming and reduce slurry leakage through the liquid film sealing effect.

[0054] In the raw material introduction and preliminary preheating stage: the first-stage piston 212 retracts, driving the spiral propeller head 322 to retreat. A negative pressure is formed between the stirring shell 311 and the conical shell 321, drawing the molten metal raw material into the stirring chamber within the conical shell 321. At this time, the motor 324 drives the spiral propeller head 322 to rotate in the opposite direction, and its convex teeth mesh with the concave teeth of a pair of stirring screws 312 to form a shearing action. When the spiral propeller head 322 rotates in the opposite direction, the tooth gap generates a high-frequency shearing force, further breaking down the blocky solid particles in the raw material. Simultaneously, the reverse rotation of the stirring screws 312, which is opposite to the rotation of the spiral propeller head 322, forms a cross-shearing action, further refining the particles. Before the slurry is introduced into the injection cylinder 211, the speed of the spiral propeller head 322 is controlled to decrease, and the slurry is guided by the spiral groove to circulate axially, ensuring uniform composition.

[0055] After mixing is complete, the screw propeller head 322 switches to pushing mode, and in coordination with the check valve 326 and the first-stage piston 212, it delivers the homogenized slurry into the first-stage pressurization chamber 214. The specific process is as follows:

[0056] Motor 324 drives screw propeller head 322 to rotate forward, and first-stage piston 212 moves forward. The combined force of these two actions generates axial thrust, pushing the slurry into the first-stage pressurization chamber 214. The slurry pressure increases under the push of the screw propeller head, opening the fan-shaped valve disc of check valve 326. The valve disc rotates around the edge axis, avoiding the central screw propeller head 322. At this time, the screw propeller head 322 has stopped rotating and is only pushed by axial movement. The opened check valve 326 and the conical surface at the front end of the screw propeller head 322 form a contraction channel, and the slurry flow rate decreases, entering the first-stage pressurization chamber 214 along the channel. As the screw propeller head 322 continues to advance with the first-stage piston 212, the volume of the first-stage pressurization chamber 214 gradually decreases, the slurry is pre-compressed, air bubbles are eliminated, and the pressure is stabilized, preparing for subsequent multi-stage pressurization.

[0057] Please see Figures 6-7 The slurry rheology control mechanism 3 also includes a temperature control mechanism 33, which includes a pair of temperature controllers 331 disposed on the mixing shell 311 and a temperature controller 331 disposed on the conical shell 321; the temperature of the slurry inside the mixing shell 311 and the conical shell 321 is controlled by the temperature controllers 331.

[0058] It should be noted that the temperature controller 331 monitors the temperature inside the mixing shell 311 and the conical shell 321 in real time, and adjusts the temperature of the slurry in different areas by heating or cooling to maintain the slurry temperature within a suitable range, thereby controlling the solid fraction of the slurry. Specifically, the mixing shell 311 is divided into a feeding section and a shearing section, while the conical shell 321 is the discharge section. Each of the feeding section, shearing section, and discharge section is equipped with a temperature controller 331, which adjusts the temperature through thermocouples and a PID controller to precisely control the solid fraction. That is, temperature control is implemented in conjunction with the mixing of the slurry inside the conical shell 321. The temperature controller 331 outside the conical shell 321 is activated, and the temperature is fed back in real time through the thermocouple. The PID controller adjusts the heating power to preheat the raw material to a semi-molten state, reducing the subsequent shear resistance. A high-frequency induction coil is set at the discharge port to detect the change in the conductivity of the slurry, that is, to calculate the solid fraction in real time through the difference in conductivity between the solid and liquid phases. The data is fed back to the temperature control mechanism 33 to achieve closed-loop control and ensure the stability of the solid fraction. It is understood that the thermocouple, PID controller and high-frequency induction coil are all existing technologies, which are not shown in the figure and will not be described in detail.

[0059] Precise temperature control ensures that the viscosity of the slurry remains within a suitable range, avoiding poor slurry flowability due to temperature fluctuations, which helps improve the consistency of ultra-thin aluminum alloy profile forming.

[0060] Example 2: The technical solution in this example differs from that in Example 1 in that: Please refer to... Figures 1-10 A semi-solid die-casting method for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles, including the aforementioned semi-solid die-casting apparatus for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles, specifically includes the following steps:

[0061] Step 1, Three-Stage Propulsion: First, the first-stage piston 212, second-stage piston 215, and third-stage piston 217 are all fully retracted. The oil supply is controlled by the hydraulic control mechanism 22, pushing the first-stage piston 212 forward to allow the slurry to enter the flow channel, completing the first-stage propulsion. Subsequently, the oil inlet is controlled by the hydraulic control mechanism 22, driving the second-stage piston 215 forward, making it move synchronously with the first-stage piston 212, achieving the second-stage relay. Finally, the oil inlet is controlled by the hydraulic control mechanism 22, driving the third-stage piston 217 forward to complete the final filling, achieving the three-stage sprint.

[0062] Step 2, Return Reset: After filling is completed, the oil circuit control mechanism 22 controls the return oil, causing the third-stage piston 217 to retract first, followed by the second-stage piston 215, and finally the last-stage piston 212, until all three retract to their initial positions.

[0063] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A semi-solid die-casting device for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles, characterized in that, Includes a multi-stage pressurization mechanism (2) connected to the injection head (1); the injection head (1) is equipped with a pressure sensor; the multi-stage pressurization mechanism (2) includes: The three-stage nested piston mechanism (21) includes an injection cylinder (211), a first-stage piston (212), a second-stage piston (215), and a third-stage piston (217). The two ends of the injection cylinder (211) are connected to the die-casting machine frame via flanges. The first-stage piston (212) is slidably connected to the injection cylinder (211) along its axial direction. The second-stage piston (215) is coaxially inserted into the first-stage piston (212). One end of the third-stage piston (217) is coaxially inserted into the second-stage piston (215), and the other end of the third-stage piston (217) extends outward from the injection cylinder (211) and is coaxially connected to the injection head (1). And an oil circuit control mechanism (22), one end of which is connected to the inside of the injection cylinder (211), and the other end of which is connected to the hydraulic pump station and used to control the first-stage piston (212), the second-stage piston (215) and the third-stage piston (217) to slide along the axial direction of the injection cylinder (211); The first-stage piston (212) has multiple first flow holes (2123), the second-stage piston (215) has a second flow hole (2153), and the third-stage piston (217) has a third flow hole (218); the slurry communicates with the injection head (1) in sequence through the first flow hole (2123), the second flow hole (2153), and the third flow hole (218); The secondary piston (215) includes a second piston rod (2151) and a second piston head (2152); the primary piston (212) includes a first piston rod (2121) and a first piston head (2122); one end of the first piston rod (2121) is coaxially connected to the first piston head (2122), and the first piston head (2122) is coaxially slidably connected inside the injection cylinder (211); one side of the first piston head (2122) and the injection cylinder (211) form a primary pressurization chamber (2). 14); One end of the second piston rod (2151) is coaxially connected to the second piston head (2152); A first guide groove is provided in the first piston rod (2121), and the second piston head (2152) is slidably connected to the first guide groove on the same axis; One side of the second piston head (2152) and the first guide groove form a secondary pressure chamber (216); A second guide groove is provided on the second piston rod (2151), and one end of the third-stage piston (217) and the second guide groove form a third-stage pressure chamber (219). The injection cylinder (211) has a slurry inlet at one end near the first-stage piston (212); the slurry inlet is equipped with a slurry rheology control mechanism (3); the slurry rheology control mechanism (3) includes a twin-screw stirring mechanism (31) and a screw control mechanism (32); the twin-screw stirring mechanism (31) is connected to the injection cylinder (211) through the screw control mechanism (32); the twin-screw stirring mechanism (31) is used to stir the slurry raw materials; the screw control mechanism (32) is used to deliver the slurry into the injection cylinder (211).

2. The semi-solid die-casting device for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles according to claim 1, characterized in that: A displacement sensor is provided between the first piston rod (2121) and the injection cylinder (211) to detect the displacement of the first piston head (2122).

3. The semi-solid die-casting device for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles according to claim 1, characterized in that: The oil circuit control mechanism (22) includes a primary oil inlet pipe (221), a secondary oil inlet pipe (223), a tertiary oil inlet pipe (225), three solenoid directional valves (228), and a proportional relief valve (229). The primary oil inlet pipe (221), the secondary oil inlet pipe (223), and the tertiary oil inlet pipe (225) are all fixed to the injection cylinder body (211). Each of the primary oil inlet pipe (221), the secondary oil inlet pipe (223), and the tertiary oil inlet pipe (225) has a solenoid directional valve (228) and a proportional relief valve (229), and the proportional relief valve (229) is located between the injection cylinder body (211) and the solenoid directional valve (228). A guide sleeve (213) is coaxially fixed to the inner wall of the injection cylinder (211), and the guide sleeve (213) is fitted onto the first-stage piston (212); the guide sleeve (213), the first piston rod (2121), the first piston head (2122), and the inner wall of the injection cylinder (211) form a first-stage hydraulic chamber (222), and the first-stage oil inlet pipe (221) communicates with the first-stage hydraulic chamber (222); an isolation ring (226) is fixed to the third-stage piston (217), and the outer wall of the isolation ring (226) abuts against the inner wall of the injection cylinder (211), so that... The isolation ring (226), the third-stage piston (217), the second piston rod (2151), the second piston head (2152), the inner wall of the first piston rod (2121), the guide sleeve (213), and the inner wall of the injection cylinder (211) form a secondary hydraulic chamber (224), and the secondary oil inlet pipe (223) is connected to the secondary hydraulic chamber (224); the third-stage piston (217), the isolation ring (226), and the injection cylinder (211) form a third-stage hydraulic chamber (227), and the third-stage oil inlet pipe (225) is connected to the third-stage hydraulic chamber (227).

4. The semi-solid die-casting device for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles according to claim 1, characterized in that: The twin-screw stirring mechanism (31) includes a stirring shell (311), a driving member (313), a feed hopper (314), and a pair of stirring screws (312); the pair of stirring screws (312) are rotatably connected to the stirring shell (311) around their axis, the driving member (313) is installed on the stirring shell (311), and the output end of the driving member (313) is connected to the pair of stirring screws (312); a feed hopper (314) is provided on the side of the stirring shell (311) near the driving member (313) and is used to introduce aluminum alloy raw material particles into the stirring shell (311).

5. The semi-solid die-casting device for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles according to claim 4, characterized in that: The spiral control mechanism (32) includes a conical shell (321), a spiral pusher head (322), a floating isolation seat (323), and a motor (324); one end of the conical shell (321) is connected to the injection cylinder (211), and the other end of the conical shell (321) is connected to the stirring shell (311); the spiral pusher head (322) is coaxially arranged inside the conical shell (321); the spiral pusher head (322) is connected to the conical shell (321). The inner wall of the spiral pusher head (322) is fitted with a conical structure, and the pitch of the spiral pusher head (322) gradually decreases from the feed end to the discharge end; a floating isolation seat (323) is installed on the first piston head (2122), the motor (324) is fixed on the floating isolation seat (323), and the output end of the motor (324) is coaxially connected to the spiral pusher head (322); a check valve (326) is provided in the stirring shell (311) near the injection cylinder (211). The spiral control mechanism (32) also includes a guide tube (325); one end of the guide tube (325) is fixed to the first piston head (2122), the guide tube (325) is slidably connected to the injection cylinder (211) along its axis, and the wire of the motor (324) is inserted into the guide tube (325).

6. The semi-solid die-casting device for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles according to claim 5, characterized in that: The slurry rheology control mechanism (3) further includes a temperature control mechanism (33), which includes a pair of temperature controllers (331) disposed on the mixing shell (311) and a temperature controller (331) disposed on the conical shell (321); the temperature of the slurry in the mixing shell (311) and the conical shell (321) is controlled by the temperature controllers (331).

7. A semi-solid die-casting method for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles, characterized in that: The semi-solid die-casting apparatus for environmentally friendly ultra-thin-walled high-strength aluminum alloy profiles as described in any one of claims 1-6 specifically includes the following steps: Step 1, Three-stage propulsion: First, the first-stage piston (212), the second-stage piston (215), and the third-stage piston (217) are all in a fully retracted state; the oil supply is controlled by the oil circuit control mechanism (22) to push the first-stage piston (212) forward, allowing the slurry to enter the flow channel and completing the first-stage propulsion; then, the oil inlet is controlled by the oil circuit control mechanism (22) to drive the second-stage piston (215) forward, making it move synchronously with the first-stage piston (212) to achieve the second-stage relay; finally, the oil inlet is controlled by the oil circuit control mechanism (22) to drive the third-stage piston (217) forward, completing the final filling and achieving the three-stage sprint; Step 2, Return Reset: After filling is completed, the oil circuit control mechanism (22) controls the return oil, so that the third-stage piston (217) retracts first, then the second-stage piston (215) retracts in sequence, and the last-stage piston (212) retracts, and finally all three are reset to their initial positions.

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