Extrusion casting forming process for magnesium and aluminum alloy

Abstract

The invention discloses a magnesium and aluminum alloy extrusion casting forming process, and belongs to the technical field of metal material forming. According to the technical scheme that injection and mold locking are carried out synchronously, the method is characterized in that 1, after molten metal is injected into a charging barrel, mold filling injection is directly started, mold filling and mold locking are started at the same time, and mold filling and mold locking force is achieved before mold filling is completely finished; after mold filling is completed, extrusion and injection are started, the mold clamping force and the injection force of extrusion are synchronously increased, the extrusion force and the mold clamping force are offset, and the stress of the mold is greatly reduced. Inclined wedge mechanisms are adopted for extrusion pressurization and mold locking, and independent linear control over extrusion force and mold locking force is achieved. The problems of large stress and short service life of the mold caused by nonlinearity of the mold clamping force in the traditional process are effectively solved, and the method has the advantages that the mold clamping force is linearly controllable, the process stability is high and the service life of the mold is long.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of metal material forming, and particularly relates to a magnesium-aluminum alloy extrusion casting forming process. BACKGROUND

[0002] Magnesium-aluminum alloys are widely used in the fields of automobiles, aerospace, electronic communication, etc. due to their low density, high specific strength and excellent corrosion resistance, and the performance and cost of the forming process directly determine the product competitiveness.

[0003] At present, the mainstream forming process of magnesium-aluminum alloy parts has many technical bottlenecks: although the gravity casting and low-pressure casting processes have low equipment cost and simple operation, the metal liquid is prone to produce casting defects such as shrinkage holes and shrinkage porosity during solidification, which leads to the difficulty of meeting the mechanical performance requirements of high-end application scenarios; the die forging process can improve the density and mechanical performance of the parts, but has problems such as low material utilization rate, high equipment locking force requirement and long production cycle; the traditional extrusion casting process has obvious deficiencies in mold life and production efficiency, the mold continuously bears high pressure during the entire forming cycle, which leads to fatigue cracks, and the locking and filling and extrusion actions cannot be synchronized, so the process stability is poor.

[0004] Especially noteworthy is that extrusion casting requires greater locking force, and the traditional extrusion process adds a locking force of about 1.3 times the expansion force to the mold before the metal liquid fills the mold, which often causes cracks and wear, resulting in product defects and making the product unusable. The existing technology has not effectively solved the coordination problem between mold stress optimization, production cycle shortening and process stability improvement, which restricts the batch production and application of high-performance light alloy parts. SUMMARY

[0005] The application provides a magnesium-aluminum alloy extrusion casting forming process to solve at least one of the above technical problems.

[0006] The technical scheme adopted by the application is as follows: A magnesium-aluminum alloy extrusion casting forming process, comprising the following steps: S1, segmented mold closing: starting the mold closing assembly to drive the movable mold assembly to slide vertically along the pull rod at first, when the electronic ruler detects that the movable mold assembly reaches the mold closing conversion position, reducing the pressure and flow of the mold closing assembly, driving the movable mold assembly to slide at low speed to the end position, so that the upper mold of the movable mold and the lower mold of the fixed mold are attached to form a sealed die cavity; S2, closing the gate: starting the gate closing assembly to drive the gate block to slide horizontally, so that the gate block teeth engage with the pull rod tooth groove, and the movable mold assembly is locked; S3, feeding the barrel: injecting magnesium-aluminum alloy liquid into the fixed mold barrel; S4, filling and locking: the injection unit is started to drive the punch to slide upward along the barrel to push the magnesium-aluminum alloy liquid into the die cavity, the upper booster assembly is started synchronously to drive the locking wedge to slide along the first T-shaped flange on the upper end of the movable die to exert the locking force on the movable die assembly, and the locking force linearly reaches the filling and locking force F1 before the die cavity is filled; S5, extrusion boosting: after the die cavity is filled with liquid, the lower booster assembly is started to linearly increase the extrusion force of the injection cylinder, and the upper booster assembly is controlled synchronously to linearly increase F1 to the extrusion locking force F2, during which the locking force and the liquid pressure in the die cavity increase synchronously; S6, pressure maintaining and solidification: F2 and the injection extrusion force are maintained to make the alloy liquid completely solidify under high pressure; S7, pressure releasing and mold opening: the lower booster assembly, the upper booster assembly and the closing assembly are started in reverse, and the movable die assembly is driven to slide upward to realize mold opening; S8, ejection of castings: the driving structure of the ejector pin in the movable die is started to make the ejector pin extend and retract to eject the formed castings; S9, assembly resetting: the injection unit and the ejector pin are driven to reset, and the one-time forming process is completed.

[0007] Further, in step S1, the mold closing assembly includes a mold closing cylinder, an electronic ruler is used to set the switching position and the end position of mold closing, and the mold closing cylinder is hinged to the side wall of the movable die assembly through a first hinge seat.

[0008] Further, in step S2, the closing assembly includes a closing cylinder, the closing cylinder drives the block to slide along the first T-shaped guide rail on the upper end of the locking wedge through the telescopic connecting rod, until the block is completely engaged with the inner tooth groove of the pull rod.

[0009] Further, in step S3, the injection unit includes an injection cylinder and a support frame supporting the injection cylinder, and the injection piston rod end of the output end of the injection cylinder is provided with a punch which is in sliding cooperation with the barrel.

[0010] Further, in step S4, the filling and locking force F1 satisfies F1=p1×A, wherein p1 is the filling pressure, and A is the die projection area; the bottom of the locking wedge is provided with a second T-shaped guide rail in sliding cooperation with the first T-shaped flange, both of which are inclined to realize the linear relationship between the locking force and the displacement of the locking wedge, and the filling and locking are synchronized during the filling and locking process, and the upper booster assembly reaches the locking force F1 before the filling is completely finished.

[0011] Further, in step S5, the extrusion locking force F2 satisfies F2=p2xA, where p2 is the extrusion pressure and A is the die projection area; the pressure increasing assembly includes a pressure increasing cylinder and a pressure increasing wedge, the pressure increasing wedge slides along the pressure increasing wedge block of the support frame, and pushes the injection cylinder to slide along the support frame to increase the extrusion force of the injection piston rod, so as to start the extrusion injection, the locking force is increased synchronously with the extrusion injection force, so that the extrusion force and the locking force are offset to each other.

[0012] Further, in step S6, the holding time is set according to the wall thickness of the casting.

[0013] Further, in step S7, the pressure relief opening mode is: first, the extrusion force of the injection cylinder is released, then the extrusion locking force F2 is released, the high-pressure opening is continued by reversing the locking assembly, the high-pressure opening distance is 2-5 mm, then the brake is released, and finally the movable die assembly is driven to slide upward quickly, and the opening distance ensures that the assembly can be taken out.

[0014] Further, in step S8, the movable die includes a movable die frame connected with the movable die plate, the upper die is connected to the lower end of the movable die frame, the ejector pin is arranged in the upper die, and the ejector pin driving structure drives the ejector pin to extend downward to eject the casting.

[0015] Further, in step S9, when the assembly is reset, the injection cylinder is started to drive the punch to reset downward along the barrel, and the ejector pin driving structure is started synchronously to reset the ejector pin upward.

[0016] Due to the adoption of the above technical scheme, the application has the following beneficial effects: 1. The present application adopts the phased locking and linear pressure increasing mechanism, so that the mold only bears the filling locking force after the filling is completed, the invalid stress time and stress size are effectively reduced, the hydraulic output is converted to linear locking force through the mechanical wedge structure, the force control precision is improved, the filling injection and locking are synchronized, and the process time is shortened.

[0017] The present application effectively reduces the stress load of the mold in the cavity stage, prolongs the service life of the mold, the combination of the segmented die clamping and the linear pressure increasing reduces the hydraulic system impact, improves the equipment operation stability, the linkage design of the locking assembly and the pressure increasing assembly shortens the process time, and the single piece production cycle is significantly shortened. The linear force output characteristics of the wedge structure ensure that the filling and pressure increasing stages are accurately matched, the locking force and the extrusion force are offset to each other in the extrusion process, the mold stress is reduced, and the mold life is improved.

[0018] 2. The present application actively applies controllable thrust through the injection unit, so that the alloy liquid completes the filling and shrinkage under the action of pressure. Compared with the independent pressure injection mechanism in the traditional extrusion casting equipment, the injection cylinder is directly supported below the barrel of the fixed die assembly, the pressure transmission path is shortened, and the energy loss is reduced.

[0019] The application realizes accurate pressure control of alloy liquid filling process, effectively eliminates shrinkage cavity defects caused by insufficient feeding, and avoids oxidation inclusion problems caused by free flow of metal liquid in traditional gravity casting through the sliding fit structure of the punch and the barrel. The integrated design of the injection unit and the mold assembly reduces the equipment floor area, and the rigid fixing characteristics of the support frame ensure the stability of the injection action and reduce the size deviation of the casting caused by mechanism vibration.

[0020] 3. The application converts the displacement of the hydraulic cylinder into linear extrusion pressure through the mechanical wedge structure, so that the extrusion pressure change process of the injection cylinder corresponds to the displacement of the booster wedge, eliminating the impact of pressure fluctuations on the mold. The application realizes linear and stable pressure increase in the extrusion stage, avoids the phenomenon of mold parting surface micro-opening caused by sudden change of extrusion pressure in traditional process, and reduces the metal liquid flash defect; at the same time, the linear pressure increasing characteristic makes the filling and extrusion actions partially overlap, shortens the production cycle of single piece, for example, the extrusion pressure can be applied before the filling is completed, improving the process continuity.

[0021] 4. The application realizes locking positioning through mechanical tooth engagement, eliminating the influence of hydraulic system response delay on locking precision. The existing technology usually adopts single-point locking method, which is prone to micro-displacement in high-pressure extrusion stage, while the application adopts a symmetrical tooth structure on both sides, which makes the locking reaction force evenly distributed on both sides of the pull rod, effectively inhibiting the micro-opening of the mold parting surface. The application realizes accurate positioning and rigid locking of the movable mold assembly at the end of the clamping, avoiding the micro-displacement of the mold caused by locking force fluctuation during the filling and extrusion stages. The multi-point engagement structure of the tooth and the tooth groove significantly improves the locking reliability, preventing the flash defect of the mold parting surface during high-pressure extrusion. The arrangement of the hinged brake cylinder reduces the installation precision requirement, and at the same time, it meets the micro-positioning adjustment requirement of the movable mold assembly during clamping.

[0022] 5. The application forms a self-locking structure on the horizontal sliding surface through the cooperation of the T-shaped guide rail and the T-shaped flange, which not only ensures the sliding degree of freedom, but also enhances the vertical load capacity. The application solves the problem of locking force attenuation caused by wear of the sliding surface in traditional locking mechanism, and avoids the uneven distribution of locking force caused by deflection of the brake block during locking. The structure improves the locking reliability through mechanical self-locking characteristics, prevents the micro-opening of the mold parting surface caused by locking force fluctuation during the filling or extrusion stage, and eliminates the metal liquid flash and gas entrapment defects.

[0023] 6. This solution uses an electronic ruler to set phased displacement control points to achieve fast and slow segmented mold closing, which avoids rigid impact and shortens idle stroke time. It can realize segmented speed control of the moving mold assembly during the mold closing process, improve production efficiency in the fast approach stage, avoid mold collision damage in the low-speed bonding stage, and at the same time, the displacement detection function of the electronic ruler ensures that the mold closing termination position is accurate and controllable, effectively improving the reliability and repeatability of the mold closing action.

[0024] 7. This application achieves a modular design for the moving mold assembly, reducing mold changeover time by approximately 40%. Simultaneously, the integrated layout of the ejector pins avoids the interference risk between the traditional ejection mechanism and the mold closing motion. The guide structure of the slider effectively suppresses vibration and displacement of the moving mold platen during high-pressure extrusion, improving the fitting accuracy of the mold parting surface by approximately 0.05 mm and reducing the probability of molten metal flash defects. Attached Figure Description

[0025] Figure 1 This is a process flow diagram of a specific embodiment of the present invention; Figure 2 This is a schematic diagram of the overall structure of a specific embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the fixed mold assembly, the moving mold assembly, and the mold closing assembly in a specific embodiment of the present invention; Figure 4 This is a front view of a specific embodiment of the present invention; Figure 5 For the present invention Figure 4 Schematic diagram of the cross-sectional structure at point AA; Figure 6 For the present invention Figure 5 Enlarged view of section B; Figure 7 For the present invention Figure 5 Enlarged view of section C; Figure 8 For the present invention Figure 5 Enlarged view of section D in the middle; Figure 9 This is a schematic diagram of the structure of the moving template in this invention; Figure 10 This is a schematic diagram of the locking wedge structure in this application.

[0026] The accompanying drawings, which are provided to further illustrate the invention and constitute a part of this invention, are illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention.

[0027] In the attached diagram: 1, pull rod; 11, tooth groove; 2, fixed mold plate; 201, fixed mold frame; 21, fixed mold; 211, barrel; 212, injection pipe; 213, lower mold; 3, movable mold plate; 31, movable mold; 311, movable mold frame; 312, upper mold; 313, ejector pin; 32, slider; 33, first T-shaped flange; 34, fixed seat; 4, clamping cylinder; 41, first hinged seat; 5, injection cylinder; 501, support frame; 51, injection piston rod; 52, punch; 53, booster wedge; 6, closing cylinder; 61, telescopic connecting rod; 62, second hinged seat; 63, brake block; 631, clamping tooth; 632, second T-shaped flange; 7, locking cylinder; 71, locking wedge; 711, first T-shaped guide rail; 712, second T-shaped guide rail; 8, booster cylinder; 81, booster wedge; 9, frame body. DETAILED DESCRIPTION

[0028] In order to more clearly illustrate the overall concept of the present application, the following will be described in detail with reference to the accompanying drawings.

[0029] In the following description, a large number of specific details are set forth in order to facilitate a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, therefore, the scope of protection of the present application is not limited by the specific embodiments disclosed below.

[0030] In addition, in the description of the present application, it should be understood that the terms "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0031] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected, or it can be communicated; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above-mentioned terms in the present application can be understood according to the specific circumstances.

[0032] In this invention, unless otherwise expressly specified and limited, the first feature "on" or "below" the second feature may be in direct contact with the first and second features, or indirect contact through an intermediate medium. In the description of this specification, references to terms such as "implementation," "example," "aspect," "specific example," or "specific example" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0033] Reference Figures 1 to 10 A magnesium and aluminum alloy extrusion casting process includes a vertically arranged tie rod 1, within which a fixed mold assembly and a moving mold assembly are arranged sequentially from bottom to top. The fixed mold assembly is fixed to the tie rod 1, and the moving mold assembly slides with the tie rod 1. A mold closing assembly is used to drive the moving mold assembly to perform vertical linear movement to cooperate with the fixed mold assembly to form a sealed die-casting cavity. A closing assembly is disposed on the upper end of the moving mold assembly and has a locking part that slides horizontally and cooperates with the tie rod 1 to lock and position the moving mold assembly. An upper pressure boosting assembly is disposed on the moving mold assembly. The upper pressurization assembly includes a mold-locking cylinder 7 and a mold-locking wedge 71, which slides vertically with the outer end of the piston rod of the mold-locking cylinder 7. A first T-shaped flange 33 is provided on the upper end of the moving mold assembly. The bottom of the mold-locking wedge 71 is provided with a second T-shaped guide rail 712 that slides with the first T-shaped flange 33. Both the first T-shaped flange 33 and the second T-shaped guide rail 712 are inclined so that the output force of the mold-locking wedge 71 on the moving mold assembly during the sliding process is linearly related to the displacement of the mold-locking wedge 71.

[0034] The tie rod 1 is a vertical track structure used to guide the movement of the moving mold. The toothed grooves 11 on its inner wall can mechanically interlock with the locking part. The mold closing assembly is a hydraulic actuator that drives the moving mold to open and close. Specifically, it can use a double-hinged cylinder in conjunction with an electronic ruler for position detection to achieve staged speed control. The locking part is a horizontally movable mechanical locking component. Specifically, it can use a brake block 63 with locking teeth 631 hinged to the cylinder connecting rod, achieving engagement and disengagement with the guide rail through telescopic movement. The mold locking wedge 71 is a wedge-shaped transmission component that converts horizontal hydraulic thrust into vertical mold locking force. Specifically, it can use a sloping guide rail and a T-shaped flange structure, the inclination angle of which determines the linear proportionality coefficient between force and displacement.

[0035] The mold closing process is divided into two stages: rapid mold closing and low-speed mold closing. An electronic ruler monitors the position of the moving mold in real time and triggers speed switching. When the moving mold reaches its final position, the closing cylinder 6 pushes the brake block 63 horizontally, causing the locking teeth 631 to engage with the guide rail groove 11 to fix the moving mold position. When the locking cylinder 7 drives the wedge to slide along the T-shaped guide rail, because the guide rail's inclination angle is constant, the locking force output to the moving mold increases linearly with the wedge displacement. This linear relationship allows only a lower locking force to be applied during the filling stage, gradually increasing to the final locking force after the cavity is filled.

[0036] Compared to existing technologies, current squeeze casting equipment applies maximum clamping force immediately after mold closing, causing the mold to bear high pressure in a hollow state. This solution, through staged clamping and a linear pressurization mechanism, ensures the mold only bears maximum clamping force after filling, effectively reducing the time of ineffective stress. Traditional processes using pure hydraulic clamping systems suffer from nonlinear response issues; this solution converts hydraulic output into linear clamping force through a mechanical wedge structure, improving force control accuracy. Existing equipment requires independent clamping and locking actions; this solution integrates a closing assembly and a pressurization assembly, achieving coordinated control of clamping force application and position locking.

[0037] Through the above technical solutions, this application effectively reduces the stress load on the mold during the cavity stage, extending the mold's service life. The combination of segmented mold closing and linear pressurization reduces hydraulic system impact and improves equipment operational stability. The linkage design of the closing assembly and pressurization assembly shortens auxiliary process time, significantly reducing the single-piece production cycle. The linear force output characteristics of the wedge structure ensure precise matching of clamping forces during the filling and pressurization stages, allowing the clamping force and extrusion force to cancel each other out during extrusion, reducing mold stress and improving mold life.

[0038] As a preferred embodiment of this application, refer to Figure 3 , Figure 4 as well as Figure 7 The fixed mold assembly has a material cylinder 211 at the lower end that communicates with the die casting cavity. The material cylinder 211 has an injection pipe 212 on its side. It also includes an injection unit. The injection unit includes an injection cylinder 5 and a support frame 501 for supporting the bottom end of the injection cylinder 5. The output end of the injection cylinder 5 has an injection piston rod 51. The end of the injection piston rod 51 is provided with a punch 52 that slides with the material cylinder 211.

[0039] The barrel 211 is a through-tube located at the lower end of the fixed mold assembly, its inner cavity communicating with the die-casting cavity. It can be implemented using a metal pipe with a high-temperature resistant coating, used to introduce molten alloy from the injection pipe 212 into the die-casting cavity. The injection pipe 212 is a tubular structure laterally connected to the barrel 211, used to quantitatively inject molten magnesium and aluminum alloy into the barrel 211. The injection unit is a pressure output device driven by the injection cylinder 5, specifically implemented using a combination of a servo hydraulic cylinder and a support frame 501, used to apply controllable thrust to the molten alloy in the barrel 211. The injection cylinder 5 is a hydraulic actuator with its output end connected to the injection piston rod 51, specifically implemented using a double-acting cylinder with a displacement sensor, used to provide precise linear driving force. The support frame 501 is a rigid frame supporting the injection cylinder 5, specifically implemented using a combination of welded steel plates and reinforcing ribs, used to maintain the axial stability of the injection cylinder 5 during operation. The injection piston rod 51 is the telescopic output component of the injection cylinder 5. It can be made of alloy steel with a hard chrome plated surface and is used to transmit the cylinder thrust to the punch 52. The punch 52 is a sealing component that slides with the barrel 211. It can be made of a composite structure of high-temperature resistant graphite ring and metal matrix and is used to form a dynamic seal in the barrel 211 and promote the flow of alloy liquid.

[0040] During the alloy liquid filling stage, after the molten metal is injected into the barrel 211 through the injection pipe 212, the injection cylinder 5 drives the injection piston rod 51 to extend along the axial direction, causing the punch 52 to slide upward inside the barrel 211. The punch 52 forms a sliding seal with the inner wall of the barrel 211, continuously pushing the alloy liquid into the die-casting cavity. The support frame 501 ensures that the movement trajectory of the injection piston rod 51 coincides with the axis of the barrel 211 by fixing the bottom position of the injection cylinder 5, avoiding seal failure caused by lateral load. The thrust of the injection cylinder 5 can be dynamically adjusted according to different needs in the filling stage. For example, a lower pressure is used in the early stage of filling to avoid splashing of molten metal, and the pressure is increased in the later stage of filling to enhance the feeding effect.

[0041] Compared to existing technologies, traditional gravity casting relies on the molten metal to fill the cavity by its own weight, which can easily lead to internal defects due to insufficient feeding pressure. This solution, however, uses an injection unit to actively apply controllable thrust, allowing the molten alloy to complete filling and feeding under pressure. Compared to the independently installed injection mechanism in traditional squeeze casting equipment, this solution directly supports the injection cylinder 5 below the barrel 211 of the fixed mold assembly, shortening the pressure transmission path and reducing energy loss.

[0042] This application achieves precise pressure control during the alloy molten metal filling process, effectively eliminating shrinkage defects caused by insufficient feeding. Simultaneously, the sliding fit structure between the punch 52 and the barrel 211 avoids oxidation inclusions caused by the free flow of molten metal in traditional gravity casting. The integrated design of the injection unit and the fixed mold assembly reduces the equipment footprint, and the rigid fixing characteristics of the support frame 501 ensure the stability of the injection action, reducing dimensional deviations in the castings caused by mechanical vibration.

[0043] As another preferred embodiment of this application, refer to Figures 2-3 as well as Figure 8 The injection cylinder 5 is slidably connected to the support frame 501 and also includes a lower pressurization assembly. The lower pressurization assembly includes a pressurization cylinder 8 and a pressurization wedge 81. The pressurization wedge 81 is vertically slidably arranged along the output end of the pressurization cylinder 8. The support frame 501 is provided with a pressurization wedge block 53 that slidably engages with the pressurization wedge 81. The bottom end of the injection cylinder 5 is slidably engaged with the pressurization wedge 81. During the sliding process, the output force of the pressurization wedge 81 on the pressurization cylinder 8 is linearly related to the displacement of the pressurization wedge 81.

[0044] The booster cylinder 8 is a hydraulic actuator used to drive the movement of the booster wedge 81. Its output end is connected to the booster wedge 81 via a piston rod to transmit thrust. The booster wedge 81 is a wedge-shaped structure with an inclined sliding surface, specifically made of surface-hardened alloy steel. Through its cooperation with the booster wedge block 53, it converts the linear motion of the booster cylinder 8 into an oblique thrust on the injection cylinder 5. The booster wedge block 53 is a guide structure set on the support frame 501, and its inclination angle matches the sliding surface of the booster wedge 81 to limit the movement trajectory. The compressive force applied to the injection cylinder 5 during the sliding process of the booster wedge 81 is directly proportional to the displacement of the booster wedge 81. This can be achieved by controlling the inclination angle of the booster wedge 81, so that the compressive force increases linearly with the increase of displacement.

[0045] When the booster cylinder 8 starts, it pushes the booster wedge 81 to slide along the booster wedge block 53. Because the bottom end of the injection cylinder 5 is in sliding engagement with the booster wedge 81, the oblique movement of the booster wedge 81 is converted into a horizontal thrust on the injection cylinder 5, forcing the injection cylinder 5 to slide along the support frame 501 to increase the extrusion force of the injection piston rod 51. The tilt angle of the booster wedge 81 is set to a fixed value, so that the output force of the booster cylinder 8 is converted into a linear extrusion force proportional to the displacement through a trigonometric function relationship. During the extrusion stage, the continuous sliding of the booster wedge 81 causes the extrusion force to gradually and linearly increase from the initial value to the target value, avoiding sudden pressure changes that could impact the mold.

[0046] This solution converts the displacement of the hydraulic cylinder into linear extrusion pressure through a mechanical wedge structure, ensuring that the change in extrusion pressure of the injection cylinder 5 strictly corresponds to the displacement of the pressure-boosting wedge 81, thus eliminating the impact of pressure fluctuations on the mold. This application achieves a linear and stable increase in pressure during the extrusion stage, avoiding the micro-opening phenomenon of the mold parting surface caused by sudden changes in extrusion pressure in traditional processes, and reducing flash defects in molten metal. At the same time, the linear pressure boosting characteristic allows the filling and extrusion actions to be partially overlapped, shortening the production cycle of a single piece. For example, extrusion pressure can be applied before filling is completed, improving process continuity.

[0047] As a specific implementation of the closing component, refer to Figures 2-6 The upper surface of the moving mold assembly is provided with a fixed seat 34. The closing assembly includes a closing cylinder 6 and a locking part includes a gate block 63. The fixed end of the closing cylinder 6 is hinged to the fixed seat 34 through the second hinge seat 62. The closing cylinder 6 has a telescopic connecting rod 61 that is hinged to the gate block 63. The gate block 63 has locking teeth 631 on both sides. The inner side of the pull rod 1 has a tooth groove 11 that cooperates with the locking teeth 631.

[0048] The closing cylinder 6 is a hydraulic actuator used to drive the horizontal sliding of the brake block 63. Specifically, it can be implemented using a double-acting hydraulic cylinder. The linear motion of its telescopic connecting rod 61 is converted into the translational motion of the brake block 63 through a hinge structure. The second hinge seat 62 is a rotary support structure connecting the closing cylinder 6 and the fixed seat 34. Specifically, it can be implemented using a U-shaped seat with a pin, allowing the closing cylinder 6 to adaptively adjust its installation angle during operation. The brake block 63 is a locking actuator with locking teeth 631. Specifically, it can be forged from high-strength alloy steel. The symmetrically distributed locking teeth 631 on both sides can form multi-point engagement with the toothed grooves 11 on the inner side of the pull rod 1. The toothed grooves 11 are toothed structures located on the inner side of the pull rod 1. Specifically, they can be arranged in a continuous trapezoidal tooth pattern, transmitting the locking reaction force through tooth surface contact.

[0049] After the mold closing action is completed, the closing cylinder 6 drives the telescopic connecting rod 61 to extend, pushing the brake block 63 to slide horizontally. Since the closing cylinder 6 is rotatably connected to the fixed seat 34 via the second hinge seat 62, the movement trajectory of the brake block 63 remains horizontal and straight. When the locking teeth 631 on both sides of the brake block 63 are fully engaged with the tooth grooves 11 on the inner side of the pull rod 1, a rigid connection is formed between the moving mold assembly and the pull rod 1, preventing any vertical displacement that may occur during the mold closing process. This mechanical locking structure disperses the mold-locking force through multi-point tooth surface contact, avoiding localized stress concentration.

[0050] This solution achieves locking and positioning through the engagement of mechanical locking teeth 631, eliminating the impact of hydraulic system response delay on mold clamping accuracy. Existing mold clamping mechanisms typically employ a single-point locking method, which is prone to slight displacement during high-pressure extrusion. This solution, however, uses a symmetrically distributed locking tooth structure on both sides of the tie rod 1, ensuring the mold clamping reaction force is evenly distributed on both sides, effectively suppressing slight opening of the mold parting surface. This application achieves precise positioning and rigid locking of the moving mold assembly at the mold closing endpoint, avoiding slight mold displacement caused by fluctuations in clamping force during filling and extrusion. The multi-point engagement structure of the locking teeth 631 and the tooth groove 11 significantly improves locking reliability, preventing flash defects on the mold parting surface during high-pressure extrusion. The articulated closing cylinder 6 arrangement reduces installation accuracy requirements while accommodating the slight position adjustment needs of the moving mold assembly during mold closing.

[0051] As a preferred embodiment of the above-described implementation method, refer to Figure 3 , Figure 6 as well as Figure 10 The upper end of the locking wedge 71 is provided with a horizontally extending first T-shaped guide rail 711, and the bottom of the gate block 63 is provided with a horizontally arranged second T-shaped flange 632 that slides and cooperates with the first T-shaped guide rail 711.

[0052] The first T-shaped guide rail 711 is a T-shaped groove structure formed on the upper end of the locking wedge 71 and extending horizontally. Specifically, it can be achieved by milling the T-shaped groove on the upper end of the locking wedge 71 using machining. This structure is used to limit the sliding trajectory of the brake block 63 and withstand the shear force during horizontal sliding. The second T-shaped flange 632 is a T-shaped strip protrusion horizontally set at the bottom of the brake block 63. Specifically, it can be achieved by casting or welding a T-shaped strip at the bottom of the brake block 63 that matches the cross-section of the first T-shaped guide rail 711. This structure guides and limits the horizontal movement of the brake block 63 through sliding cooperation with the first T-shaped guide rail 711.

[0053] When the closing cylinder 6 drives the telescopic connecting rod 61 to extend, the second T-shaped flange 632 at the bottom of the brake block 63 slides horizontally along the first T-shaped guide rail 711 of the locking wedge 71. Due to the guiding effect of the T-shaped structure, the brake block 63 always maintains horizontal movement during the sliding process, avoiding skewing or jamming caused by uneven force. When the locking teeth 631 on both sides of the brake block 63 are fully engaged with the tooth groove 11 on the inner side of the pull rod 1, the contact surface between the second T-shaped flange 632 and the first T-shaped guide rail 711 forms a rigid support, which can effectively resist the vertical component force applied by the locking wedge 71 and ensure the stability of the locking state.

[0054] This application utilizes the cooperation of a T-shaped guide rail and a T-shaped flange to form a self-locking structure on the horizontal sliding surface, ensuring both sliding freedom and enhanced resistance to vertical loads. This application solves the problem of clamping force attenuation caused by sliding surface wear in traditional locking mechanisms, and avoids uneven clamping force distribution caused by the misalignment of the gate block 63 during locking. This structure improves locking reliability through its mechanical self-locking characteristics, preventing slight opening of the mold parting surface due to clamping force fluctuations during filling or extrusion, thereby eliminating molten metal flash and air entrapment defects.

[0055] As a preferred embodiment of the mold assembly in this application, refer to Figures 2-4 The mold closing assembly includes a mold closing cylinder 4 and an electronic ruler. The fixed end of the mold closing cylinder 4 is fixedly connected to the side wall of the pull rod 1. The telescopic end of the mold closing cylinder 4 is hinged to the side wall of the moving mold assembly through the first hinge seat 41. The electronic ruler is used to set the mold closing transition position and the end position.

[0056] The mold-closing cylinder 4 is an actuator that achieves linear movement of the moving mold assembly through hydraulic drive. Specifically, it can be implemented using a double-acting hydraulic cylinder. Its fixed end is connected to the side wall of the tie rod 1, and its telescopic end is connected to the moving mold assembly via a hinge. It is used to provide the driving force required for the opening and closing of the moving mold assembly. The electronic ruler is a position sensor used to detect the displacement of the moving mold assembly. Specifically, it can be implemented using a magnetostrictive linear displacement sensor. By setting the displacement transition point and endpoint during the mold-closing process, it controls the movement speed and pressure output of the mold-closing cylinder 4 at different stages.

[0057] The mold-closing cylinder 4 drives the moving mold assembly to move vertically linearly along the tie rod 1 via a hinged connection. In the initial stage of mold closing, the moving mold assembly is driven at a high speed to quickly approach the fixed mold assembly. When the electronic ruler detects that the moving mold assembly has reached the preset transition position, the mold-closing cylinder 4 automatically switches to a low-pressure, low-speed mode, allowing the moving mold assembly to complete the final contact with the fixed mold assembly at a controllable speed. The electronic ruler monitors the displacement of the moving mold assembly in real time, triggering a signal to stop the mold-closing cylinder 4 when it reaches the endpoint, ensuring that the moving mold assembly and the fixed mold assembly precisely close to form a sealed cavity.

[0058] Compared to existing technologies, traditional mold closing processes rely on single-speed control, which can easily lead to mold collisions due to excessive speed or prolonged cycles due to excessively low speed. This solution, however, uses an electronic ruler to set staged displacement control points, achieving segmented mold closing at both fast and slow speeds. This avoids rigid impacts and shortens idle travel time. Existing technologies lack precise position feedback, relying on mechanical limits for the mold closing endpoint. This solution uses an electronic ruler to detect displacement in real time, precisely controlling the stopping position of the moving mold assembly and eliminating positioning errors caused by mechanical wear.

[0059] This application enables segmented speed control of the mold closing process of the moving mold assembly, improving production efficiency during the rapid approach stage and avoiding mold collision damage during the low-speed bonding stage. At the same time, the displacement detection function of the electronic ruler ensures that the mold closing termination position is precise and controllable, effectively improving the reliability and repeatability of the mold closing action.

[0060] As a specific implementation of the moving model assembly, refer to Figures 5-7 as well as Figure 9 The moving mold assembly includes a moving template 3. The side wall of the moving template 3 is provided with a slider 32 that slides with the pull rod 1. The lower end of the moving template 3 is fixedly connected to a moving mold 31. The moving mold 31 includes a moving mold frame 311 that is fixedly connected to the moving template 3. The lower end of the moving mold frame 311 is fixedly connected to an upper mold 312. The upper mold 312 is provided with a retractable ejector pin 313.

[0061] The moving template 3 is a movable component that supports the moving mold 31 and enables the mold closing action. It can be formed by welding or casting high-strength steel plates. The sliding block 32 on its side wall, in sliding engagement with the tie rod 1, ensures stable movement of the moving mold assembly along a predetermined trajectory. The sliding block 32 is a guide component that enables the sliding connection between the moving template 3 and the tie rod 1; lubrication grooves or self-lubricating bearings are used to reduce sliding friction resistance. The moving mold 31 refers to the movable mold 31 assembly that cooperates with the fixed mold 21 to form the die-casting cavity. It can be integrally machined from high-temperature resistant mold steel. The moving mold frame 311 is detachably connected to the moving template 3 via bolts. The ejector pin 313 is a telescopic component used to eject the formed casting, and its telescopic action is achieved through a built-in spring or hydraulic drive mechanism.

[0062] The moving template 3 forms a sliding pair with the tie rod 1 via the slider 32 on the side wall. Driven by the mold closing cylinder 4, it moves vertically, causing the moving mold frame 311 of the moving mold 31 and the upper mold 312 to close with the lower mold 213 of the fixed mold 21 to form a die-casting cavity. The ejector pin 313 extends downward after the casting solidifies via a built-in drive mechanism, ejecting the molded part from the mold cavity. The guiding effect of the slider 32 effectively limits the lateral displacement of the moving template 3 during movement, ensuring precise alignment of the upper mold 312 and the lower mold 213 during mold closing.

[0063] This solution, by setting a detachable moving mold frame 311, allows the moving mold 31 to be quickly replaced independently of the moving template 3. In the prior art, ejector pins 313 are mostly located on the side of the fixed mold 21, requiring an additional ejection mechanism after mold opening. However, this solution integrates the ejector pins 313 into the upper mold 312 of the moving mold 31, allowing direct ejection after mold opening, thus shortening the production cycle. This application achieves a modular design of the moving mold assembly, reducing mold changeover time by approximately 40%. Simultaneously, the integrated layout of the ejector pins 313 avoids the interference risk between traditional ejection mechanisms and mold closing movements. The guiding structure of the slider 32 effectively suppresses vibration and displacement of the moving template 3 during high-pressure extrusion, improving the fitting accuracy of the mold parting surface by approximately 0.05 mm and reducing the probability of molten metal flash defects.

[0064] As a preferred embodiment of the mold assembly, refer to Figures 2-5 as well as Figure 7 The fixed mold assembly includes a fixed template 2, and a fixed mold 21 that cooperates with the moving mold 31 is fixedly connected to the upper end of the fixed template 2. The fixed mold 21 includes a fixed mold frame 201 that is fixedly connected to the fixed template 2. A lower mold 213 is fixedly connected to the upper end of the fixed mold frame 201. The upper mold 312 and the lower mold 213 cooperate to form a sealed die-casting cavity.

[0065] The fixed template 2 is a vertically fixed support structure, rigidly connected to the lower end of the tie rod 1 by bolts, used to bear the installation load and molding pressure of the fixed mold 21. The fixed mold 21 is a fixed component that cooperates with the moving mold 31 to form a cavity. Specifically, it can adopt a split structure. The fixed mold frame 201 serves as a transitional connector, precisely positioned and welded to the fixed template 2 by locating pins. The lower mold 213 is fastened to the upper surface of the fixed mold frame 201 by countersunk bolts, facilitating quick replacement after mold wear. The fixed mold frame 201 is a transitional connection structure, which can be a rectangular steel block with locating steps. Its bottom surface is machined with mounting holes that match the fixed template 2, and its upper surface has locating bosses that cooperate with the lower mold 213, ensuring the coaxiality and flatness of the lower mold 213 during installation. The lower mold 213 is the fixed part of the cavity. Specifically, it can be made of H13 hot work die steel through vacuum heat treatment. Its profile is complementary to the upper mold 312. When the mold is closed, it is precisely aligned with the upper mold 312 through the guide pillar to form a closed die casting cavity.

[0066] The fixed template 2 serves as the basic support component, forming a stable frame structure with the tie rod 1 through a rigid connection. The fixed mold frame 201 serves as an intermediate transition component, ensuring a reliable connection between the fixed template 2 and the lower mold 213, while also reducing processing difficulty through its split design. The lower mold 213 is fixed to the upper surface of the fixed mold frame 201 by bolts. During mold closing, the upper mold 312 of the moving mold 31 closes with the lower mold 213 under the drive of the mold closing assembly. The parting surface of the cavity achieves self-alignment and sealing through the cooperation of guide pillars and conical surfaces. After the closing assembly completes the positioning of the moving mold, the mating surfaces of the upper mold 312 and the lower mold 213 fit tightly under the action of the clamping force, forming a gapless sealed cavity to prevent flash or leakage of molten metal during high-pressure filling.

[0067] This solution utilizes a combination design of a split fixed mold frame 201 and a detachable lower mold 213 to ensure the structural strength of the fixed mold plate 2 while enabling rapid mold replacement, thus preventing the entire mold set from being scrapped due to localized wear. Furthermore, the rigid connection between the fixed mold frame 201 and the fixed mold plate 2, combined with the positioning boss structure of the lower mold 213, effectively improves the coaxiality and flatness of the mold installation, reduces rigid impacts caused by mold misalignment during mold closing, and extends the mold's service life.

[0068] This application solves the problems of complex structure and low mold replacement efficiency of traditional fixed mold components. Through the cooperation design of split mounting base and detachable lower mold 213, the mold can be quickly maintained and replaced while ensuring cavity sealing. The rigid connection structure between fixed mold plate 2 and fixed mold frame 201 effectively improves the overall rigidity of the mold system, avoids slight displacement of the mold due to insufficient support during high-pressure filling, thereby reducing casting flash and air entrapment defects and improving the stability of molding quality.

[0069] As a preferred option, refer to Figure 1 The lower end of the pull rod 1 is provided with a downward-extending frame 9.

[0070] The frame 9 is a load-bearing frame connected to the bottom of the tie rod 1. Specifically, it can be a welded truss or an assembled steel structure. Its downward extension structure can increase the overall height of the equipment and form a stable support base. The extension length can be set to 500-1500mm according to the height requirements of the die-casting machine.

[0071] Tie rod 1 and frame 9 form an integral load-bearing structure, transferring the vertical load generated by the clamping cylinder 7 to the ground during die casting. When the moving mold assembly slides along tie rod 1, frame 9 reduces the pressure per unit area by increasing the contact area. For example, during the clamping stage, the linear force applied by the clamping wedge 71 is transmitted to frame 9 through tie rod 1, and then dispersed to the foundation by the anti-slip pads at the bottom of frame 9. The extension of frame 9 can integrate hydraulic pipeline channels, arranging the oil supply lines of the booster cylinder 8 within the internal cavity of frame 9.

[0072] This solution extends the frame 9 downwards to form an extended support surface, lowering the center of gravity of the die-casting machine and making the load distribution more uniform, effectively suppressing fatigue deformation of the tie rod 1 under alternating stress. This application can enhance the operational stability of the equipment, prevent the tie rod 1 from undergoing plastic deformation due to long-term high pressure, and at the same time provide concealed space for hydraulic pipelines and electrical lines, reducing the risk of external environmental interference to critical components of the equipment.

[0073] Reference Figures 1-10 The method for casting using this application specifically includes the following steps: S1. Segmented mold closing: The mold closing assembly is started and the moving mold assembly is driven to slide quickly vertically along the tie rod 1. When the electronic ruler detects that the moving mold assembly has reached the mold closing transition position, the pressure and flow of the mold closing assembly are reduced, and the moving mold assembly is driven to slide slowly to the end position, so that the upper mold 312 of the moving mold and the lower mold 213 of the fixed mold fit together to form a sealed die casting cavity. S2, Closing: Start the closing assembly, which drives the gate block 63 to slide horizontally, so that the gate block 63's locking teeth 631 engage with the tooth groove 11 of the pull rod 1, locking the moving module assembly; S3, Material barrel 211 feeding: Inject magnesium and aluminum alloy liquid into the fixed mold material barrel 211; S4. Filling and clamping: Start the injection unit, drive the punch 52 to slide upward along the barrel 211, push the magnesium and aluminum alloy liquid to the die casting cavity, and simultaneously start the upper pressure component to push the clamping wedge 71 to slide obliquely along the first T-shaped flange 33 at the upper end of the moving mold, apply clamping force to the moving mold component, and before the die casting cavity is filled, the clamping force reaches the linear filling clamping force F1; S5, Extrusion Pressure Boosting: After the cavity is filled with liquid, the lower pressure boosting component is activated to push the injection cylinder 5 to linearly increase the extrusion pressure. Simultaneously, the upper pressure boosting component is controlled to linearly increase F1 to the extrusion clamping force F2. During this process, the clamping force and the liquid pressure filled into the die-casting cavity increase synchronously. S6, Pressure Holding and Solidification: Maintain F2 and injection pressure to ensure complete solidification of the alloy liquid under high pressure; S7, Pressure relief and mold opening: Reverse start of the lower booster component, upper booster component, and closing component, then drive the moving mold component to slide upward to achieve mold opening; S8. Casting ejection: Activate the drive structure of ejector pin 313 in the moving mold to make ejector pin 313 extend and retract to eject the formed casting; S9, Component Reset: Drive the injection unit and ejector pin 313 to reset, completing the one-time molding process.

[0074] During the segmented mold closing process, the moving mold assembly first quickly approaches the fixed mold assembly to reduce idle travel time. After reaching the transition position, it switches to low-speed movement to avoid mold collision. The closing cylinder 6 drives the brake block 63 to slide horizontally and engage with the toothed groove 11 of the pull rod 1, forming a mechanical lock to prevent displacement of the moving mold. During the filling stage, the clamping cylinder 7 pushes the clamping wedge 71 to slide along the inclined guide rail. Through the inclined plane, the horizontal thrust is converted into a vertical clamping force. This clamping force increases linearly with the wedge displacement and matches the filling pressure, and increases synchronously and linearly with the filling pressure. After the alloy liquid fills the cavity, the booster cylinder 8 pushes the injection cylinder 5 through the wedge mechanism to increase the extrusion pressure. At the same time, the clamping cylinder 7 continues to advance, linearly increasing the clamping force to the value required for high-pressure extrusion. During the pressure holding stage, the clamping force and extrusion pressure are maintained until the alloy liquid is completely solidified. When depressurizing, the forces of each cylinder are released in reverse order. Finally, the casting is ejected by the ejector pin 313 and each component is reset.

[0075] Traditional processes employ a single-speed mold closing mechanism, with the clamping force reaching its maximum before filling, resulting in the mold enduring prolonged high pressure and alternating stress. This method, however, reduces mold impact through segmented mold closing and dynamically adjusts the clamping force during filling, ensuring the mold only bears high pressure at necessary stages, thus reducing fatigue damage. Traditional processes have a fixed sequence of clamping and filling actions; this method allows filling and clamping to occur simultaneously with extrusion pressurization, shortening the molding cycle. Furthermore, traditional equipment exhibits a non-linear relationship between clamping force and displacement; this method achieves linear clamping force output through the inclined sliding of wedges and T-shaped guides, ensuring force control accuracy and process stability.

[0076] This application reduces high-pressure loads on the mold during unnecessary stages, extending its service life. Segmented mold closing and dynamic clamping force control prevent rigid impacts and micro-opening of the parting surface, reducing flash and air entrapment defects. Synchronized filling, clamping, and extrusion pressurization shorten the single-piece production cycle, meeting the demands of high-efficiency production. Linear force output characteristics ensure precise matching of clamping force and extrusion force to process requirements, improving casting density and mechanical properties.

[0077] This application further proposes that in step S1, the mold closing assembly includes a mold closing cylinder 4, an electronic ruler is used to set the mold closing transition position and the end position, and the mold closing cylinder 4 is hinged to the side wall of the moving mold assembly through the first hinge seat 41.

[0078] As the moving mold assembly slides along the tie rod 1, the electronic ruler monitors its displacement in real time. When the moving mold assembly reaches the preset mold closing transition position, the control system immediately adjusts the oil supply pressure and flow rate of the mold closing cylinder 4, reducing its output thrust and switching to a low-speed motion mode. During this process, the first hinge seat 41 allows a small angular offset between the mold closing cylinder 4 and the moving mold assembly, thereby eliminating motion interference caused by machining errors or thermal deformation. Finally, the moving mold assembly smoothly contacts the lower mold 213 of the fixed mold at a low speed, ensuring that the parting surface is completely fitted to form a sealed cavity.

[0079] Compared to existing technologies, traditional equipment typically employs rigidly connected mold-closing mechanisms, which cannot adapt to trajectory deviations during the movement of the moving mold components, easily leading to mold collisions or seal failures. The first hinge seat 41, by introducing a flexible connection mechanism, effectively absorbs the accumulated errors of the motion system, preventing lateral stress generated during mold closing from damaging the mold and tie rod 1. Simultaneously, the coordinated control of the electronic ruler and the mold-closing cylinder 4 enables precise switching of motion speed, resolving the contradiction between inertial impact during high-speed mold closing and precise positioning at low speeds.

[0080] Through the above technical solution, this application can significantly improve the positioning accuracy and stability of the mold closing action, reduce the risk of wear and deformation on the mold parting surface, and reduce equipment maintenance costs. This design is particularly suitable for scenarios with stringent requirements for mold closing accuracy in magnesium and aluminum alloy die casting processes, and can effectively avoid problems such as flash or dimensional deviations in castings caused by poor mold closing.

[0081] Reference Figures 1-10 This application further proposes a closing assembly for a magnesium and aluminum alloy extrusion casting process, including a closing cylinder 6. The closing cylinder 6 drives the gate block 63 to slide along the first T-shaped guide rail 711 at the upper end of the locking wedge 71 via a telescopic connecting rod 61 until the locking teeth 631 on both sides of the gate block 63 are fully engaged with the inner tooth groove 11 of the pull rod 1.

[0082] The closing cylinder 6 pushes the brake block 63 horizontally along the first T-shaped guide rail 711 via the telescopic connecting rod 61. When the brake block 63 reaches the predetermined position, its two side locking teeth 631 fully engage with the tooth groove 11 of the pull rod 1, forming a rigid lock. During this process, the first T-shaped guide rail 711 guides the sliding path of the brake block 63, ensuring the meshing accuracy of the locking teeth 631 and the tooth groove 11. The meshing contact surface between the brake block 63 and the tooth groove 11 is made of a high-hardness material to prevent locking failure due to deformation under force during the locking process.

[0083] Compared with existing technologies, traditional mold-locking devices typically use a single hydraulic cylinder for direct locking, which results in uneven application of locking force and easy wear of the locking mechanism. This solution, through the cooperation structure of T-shaped guide rail and locking teeth 631-tooth groove 11, makes the distribution of locking force more uniform. At the same time, multi-point meshing reduces local stress concentration and extends the service life of the locking mechanism.

[0084] Through the above technical solution, this application achieves rapid and reliable locking of the moving mold assembly, avoiding the phenomenon of slight opening of the mold parting surface caused by insufficient clamping force during the filling stage. At the same time, by replacing pure hydraulic clamping with mechanical meshing locking, the continuous pressure load on the clamping cylinder 7 is reduced, and the stability of equipment operation is improved.

[0085] This application further proposes that the injection unit in step S3 includes an injection cylinder 5 and a support frame 501 supporting the injection cylinder 5. The injection piston rod 51 at the output end of the injection cylinder 5 is provided with a punch 52, and the punch 52 is slidably engaged with the barrel 211.

[0086] The injection cylinder 5 is fixed to the equipment base by a support frame 501. The injection piston rod 51, driven by hydraulic pressure, drives the punch 52 to slide along the axis of the barrel 211. The sliding fit clearance between the punch 52 and the inner wall of the barrel 211 is precision machined to ensure sealing during the alloy liquid injection process. The rigid structure of the support frame 501 effectively absorbs vibrations generated during injection, preventing the punch 52 from jamming or leaking due to force displacement of the injection cylinder 5. During the filling stage, the injection cylinder 5 drives the punch 52 to move upwards at a set speed, smoothly pushing the alloy liquid into the die-casting cavity. The stability of the support frame 501 ensures precise control of the filling pressure and speed.

[0087] This design, through the rigid connection between the support frame 501 and the injection cylinder 5, ensures that the axis of motion of the punch 52 always coincides with the axis of the barrel 211, reducing the impact of lateral forces on the sealing surface. Simultaneously, the integrated transmission structure of the injection piston rod 51 and the punch 52 avoids the clearance error of traditional separate connecting parts, ensuring efficient transmission of extrusion force.

[0088] This application solves the problem of filling pressure fluctuation caused by the loose structure of traditional injection units. The rigid fixation of the support frame 501 and the precise fit of the punch 52 make the alloy liquid pushing process more stable, reducing the internal porosity defects of the casting caused by sudden pressure changes. The combined design of the injection cylinder 5 and the support frame 501 extends the service life of the injection unit and reduces the frequency of equipment maintenance due to vibration.

[0089] This application further proposes a magnesium and aluminum alloy extrusion casting process, including step S4 in which the filling clamping force F1 satisfies F1=p1×A, where p1 is the filling pressure and A is the die casting projected area; the bottom of the clamping wedge 71 is provided with a second T-shaped guide rail 712 that slides with the first T-shaped flange 33, and both are inclined to achieve a linear relationship between the clamping force and the displacement of the clamping wedge 71. During the filling and clamping process, filling and clamping are carried out synchronously. Before the filling is completely finished, the upper pressure component reaches the clamping force F1.

[0090] During the filling stage, as the injection unit pushes the molten metal into the mold cavity, the upper pressure boosting component drives the clamping wedge 71 to slide along the first T-shaped flange 33 of the moving mold assembly. Since the inclination angle between the second T-shaped guide rail 712 and the first T-shaped flange 33 is fixed, a linear relationship is formed between the wedge displacement and the clamping force. For example, when the filling pressure p1 reaches a set value, the upper pressure boosting component adjusts the cylinder pressure according to the displacement sensor signal, causing the clamping force F1 to gradually increase as the filling process progresses. Before the molten metal completely fills the mold cavity, the clamping force has increased to the value of F1 = p1 × A, at which point the mold cavity parting surface is completely sealed.

[0091] Compared to existing technologies, in traditional processes, the clamping force is usually applied after filling is complete via an independent pressurization mechanism. This results in insufficient clamping force when the cavity pressure suddenly increases in the later stages of filling, which can easily lead to micro-opening of the parting surface. In contrast, this solution uses an inclined guide rail structure to linearly correlate the clamping force with the wedge displacement, enabling real-time matching of the clamping action with the filling process and avoiding the risk of mold separation caused by pressure fluctuations.

[0092] Through the above technical solution, this application achieves synchronous control of the filling process and the increase in clamping force, effectively suppressing the micro-opening phenomenon of the parting surface at the end of the filling process and reducing flash and internal porosity defects in the casting. Simultaneously, the linear growth characteristic of the clamping force reduces the probability of the mold being subjected to impact loads, extending the mold's service life. This solution also simplifies the clamping force control logic, improving process stability and equipment response speed.

[0093] This application further proposes that in step S5, the extrusion clamping force F2 satisfies F2 equal to p2 multiplied by A, where p2 is the extrusion pressure and A is the die-casting projected area; the lower pressure boosting component includes a pressure boosting cylinder 8 and a pressure boosting wedge 81, the pressure boosting wedge 81 slides along the pressure boosting wedge block 53 of the support frame 501, pushing the injection cylinder 5 to slide along the support frame 501 to increase the extrusion force of the injection piston rod 51, and start extrusion injection, the clamping force and the extrusion injection force increase synchronously, so that the extrusion force and the clamping force cancel each other out.

[0094] Among them, the extrusion clamping force F2 is the final clamping force applied after the cavity is filled with liquid. Specifically, it can be achieved by using a pressure sensor to monitor the extrusion pressure of the injection cylinder 5 in real time, and by using a closed-loop control system to keep the clamping force and the extrusion pressure increasing synchronously and linearly. This parameter setting can ensure that the mold parting surface maintains a sealed state under high pressure.

[0095] After the cavity is filled with molten alloy, the booster cylinder 8 drives the booster wedge 81 to slide along the wedge block of the support frame 501, pushing the injection cylinder 5 to move as a whole to increase the extrusion force of the punch 52. At the same time, the upper booster assembly synchronously increases the clamping force according to the displacement signal of the injection cylinder 5, so that the increase in extrusion force and the increase in clamping force always maintain a dynamic balance. Since the slope angle of the wedge mechanism is precisely calculated, the extrusion force and clamping force can increase synchronously and linearly according to a preset ratio until the final extrusion clamping force F2 is reached. During this process, the extrusion force and clamping force on the parting surface of the mold form a mutually canceling mechanical relationship, effectively preventing the mold from slightly opening.

[0096] This solution achieves real-time synchronous linear growth of extrusion pressure and clamping force through the synergistic effect of the wedge mechanism and closed-loop control system, completely eliminating the micro-gap problem during the pressure conversion stage. The flash defects caused by asynchronous pressure, common in existing technologies, are fundamentally solved in this solution. This application ensures that the mold remains in a state of stress balance during the high-pressure extrusion stage, avoiding surface quality defects in the casting caused by micro-opening of the parting surface. Because the clamping force and extrusion pressure strictly follow a linear synchronous growth relationship, the stress distribution on the mold is more uniform, significantly reducing mold wear caused by localized stress concentration. This technical solution also improves the controllability of the process, providing a reliable guarantee for the stable production of complex thin-walled castings.

[0097] This application further proposes that, in the pressure holding solidification step, the pressure holding time be set according to the casting wall thickness.

[0098] Holding time is the duration for which the extrusion clamping force and injection pressure are maintained. It can be set through a process parameter control system, adjusting the holding time according to the wall thickness differences in different areas of the casting to ensure continuous pressure compensation during solidification. Casting wall thickness refers to the maximum thickness of the formed casting cross-section. Establishing a correlation between wall thickness and holding time helps prevent internal shrinkage defects caused by premature pressure release during solidification.

[0099] After the molten alloy completely fills the mold cavity, the pressurizing assembly maintains the clamping force and injection pressure, at which point the molten alloy begins to solidify and shrink. For areas with thicker walls, the solidification time is longer, requiring an extended holding time to ensure continuous feeding of the thick-walled sections with liquid metal during the solidification and shrinkage phase. For thin-walled areas, the solidification time is shorter, allowing for a shorter holding time. For example, when the maximum wall thickness of the casting is detected to be 15 mm, the control system automatically matches the corresponding holding time parameter, maintaining the pressure until that thickness area completes solidification. The holding time can be set through a pre-established process database containing a mapping relationship between different wall thicknesses and corresponding holding times.

[0100] Compared to existing technologies, traditional processes typically employ fixed holding times or empirical estimates, failing to consider the impact of casting structural variations on the solidification process. For instance, in complex castings containing both thick and thin walls, a fixed holding time may lead to insufficient feeding in thick-walled areas or excessive holding time in thin-walled areas. The former results in internal defects, while the latter increases energy consumption and mold thermal load. This solution dynamically matches the holding time with the actual casting wall thickness, allowing the pressure maintenance duration to precisely adapt to the solidification requirements of different regions.

[0101] Through the above technical solution, this application effectively solves the problem of insufficient feeding caused by the mismatch between the holding time and the casting structure, ensuring the internal density of the casting while avoiding energy waste caused by excessive holding pressure. By precisely controlling the pressure holding time, the ineffective exposure time of the mold under high temperature and high pressure can be reduced, thereby reducing the risk of thermal fatigue damage to the mold.

[0102] This application further proposes the following pressure relief and mold opening sequence: first release the extrusion pressure of the injection cylinder 5, then release the extrusion clamping force F2, and continue to reverse the start of the clamping assembly to achieve high-pressure mold opening. After the high-pressure mold opening distance is 2~5mm, release the brake, and finally drive the moving mold assembly to slide up quickly. The mold opening distance ensures that the assembly can be removed.

[0103] During the pressure relief and mold opening process, the lower pressure boosting component first controls the extrusion pressure of the injection cylinder 5 to zero, eliminating the residual injection reaction force after the alloy liquid solidifies. Then, the upper pressure boosting component moves in the opposite direction, causing the clamping wedge 71 to retract, and the clamping force F2 gradually decreases to zero. Next, the mold closing cylinder 4 reverses its oil supply, driving the moving mold assembly to retract slightly, allowing the mold parting surface to slowly separate within a 2-5mm range. At this time, the mold is still mechanically locked by the closing assembly. When the moving mold displacement reaches the set value, the closing cylinder 6 drives the brake block 63 to disengage from the tooth groove 11 of the pull rod 1, releasing the mechanical lock. Finally, the mold closing cylinder 4 switches to high-speed mode, driving the moving mold assembly to quickly slide upwards to the fully open position. This sequence, through the coordinated control of staged pressure relief and mechanical constraints, ensures that the mold parting surface remains controllable throughout the pressure relief process.

[0104] Compared to existing technologies, traditional processes typically involve directly releasing the brake and rapidly opening the mold after pressure relief. This causes the mold parting surface to suddenly separate under residual stress, easily leading to surface scratches on the casting or mold collisions. This solution, however, achieves initial separation of the mold during the high-pressure mold opening stage by partially separating the mold and maintaining mechanical locking. This allows the parting surface to complete initial separation before the pressure is fully released. Simultaneously, the delayed release mechanism of the brake assembly effectively avoids the risk of micro-opening caused by sudden changes in mold stress.

[0105] Through the above technical solution, this application solves the problem of micro-opening of the parting surface caused by sudden stress change in the mold during the pressure relief stage in the traditional extrusion casting process, reduces the wear of the mold caused by instantaneous stress concentration, and improves the safety and process stability of the mold opening process by coordinating the staged pressure relief and mechanical locking.

[0106] This application further proposes a magnesium and aluminum alloy extrusion casting process, wherein the moving mold includes a moving mold frame 311 connected to the moving mold plate 3, the lower end of the moving mold frame 311 is connected to the upper mold 312, and the ejector pin 313 is disposed in the upper mold 312. The ejector pin 313 driving structure drives the ejector pin 313 to extend and retract downward to eject the casting.

[0107] After the casting has solidified under pressure, the moving mold frame 311 moves upward along with the moving template 3 to open the mold. At this time, the ejector pin 313 driving structure pushes the ejector pin 313 downward along the guide hole reserved inside the upper mold 312. The end of the ejector pin 313 contacts the surface of the casting and applies an ejection force, causing the casting to separate from the inner wall of the upper mold 312. The stroke of the ejector pin 313 can be adjusted according to the height of the casting. After the ejection action is completed, the ejector pin 313 driving structure drives the ejector pin 313 to retract to its original position to avoid interfering with the subsequent mold closing action.

[0108] This solution integrates the ejector pin 313 inside the moving mold, using the ejector pin 313 to drive the structure directly onto the bottom of the casting, preventing the casting from tilting or deforming during ejection. It also simplifies the external structure of the mold. This application achieves uniform force control during the casting demolding process, effectively preventing surface indentations or internal cracks caused by ejection, and improving the dimensional accuracy of the molded parts. The integrated design of the ejector pin 313 and the mold shortens the ejection stroke, reduces auxiliary operation time, and increases the continuous production cycle time.

[0109] This application further proposes a magnesium and aluminum alloy extrusion casting process. In step S9, when the component is reset, the injection cylinder 5 is activated to drive the injection piston rod 51 to drive the punch 52 to reset downward along the barrel 211. At the same time, the ejector pin 313 drive structure is activated to reset the ejector pin 313 upward.

[0110] After the casting is ejected, the piston rod of the injection cylinder 5 drives the punch 52 to slide downwards along the inner wall of the barrel 211 to its initial position. Simultaneously, the ejector pin 313 retracts into the mold via hydraulic or mechanical transmission. During this process, the reset actions of the punch 52 and the ejector pin 313 are synchronized through a control system to ensure no interference between their trajectories. As the punch 52 descends, it uses the mating relationship between its end face and the inner wall of the barrel 211 to scrape away residual molten metal. As the ejector pin 313 ascends, a limit sensor confirms the reset endpoint, providing a clean mold environment for the next molding cycle.

[0111] This solution achieves synchronized control of the injection cylinder 5 and the ejector pin 313 drive structure, enabling their reset actions to coordinate in time and space. This shortens the equipment reset cycle and avoids the risk of mold collision caused by component misalignment. It solves the problem of low equipment efficiency caused by asynchronous reset of the punch 52 and ejector pin 313 in traditional extrusion casting. The coordinated control shortens the molding cycle and reduces the contamination of the mold cavity by residual molten metal, ensuring the process stability of continuous production.

[0112] For any parts not mentioned in this invention, existing technologies can be used or referenced.

[0113] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0114] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A magnesium-aluminum alloy extrusion casting process, characterized in that, Includes the following steps: S1. Segmented mold closing: The mold closing assembly is started and the moving mold assembly is driven to slide quickly vertically along the tie rod. When the electronic ruler detects that the moving mold assembly has reached the mold closing transition position, the pressure and flow of the mold closing assembly are reduced, and the moving mold assembly is driven to slide slowly to the end position, so that the upper mold of the moving mold and the lower mold of the fixed mold fit together to form a sealed die casting cavity. S2, Closing: Start the closing assembly, which drives the gate block to slide horizontally, so that the gate block teeth engage with the pull rod teeth, locking the stop module assembly; S3, Barrel Feeding: Injecting magnesium and aluminum alloy liquid into the fixed mold barrel; S4. Filling and clamping: Start the injection unit to drive the punch to slide upward along the barrel and push the magnesium and aluminum alloy liquid into the die casting cavity. Simultaneously start the upper pressure component to push the clamping wedge to slide along the first T-shaped flange at the upper end of the moving mold and apply clamping force to the moving mold component. Before the die casting cavity is filled, the clamping force linearly reaches the filling clamping force F1. S5. Extrusion Pressure Boosting: After the cavity is filled with liquid, the lower pressure boosting component is activated to push the injection cylinder to linearly increase the extrusion pressure. Simultaneously, the upper pressure boosting component is controlled to linearly increase F1 to the extrusion clamping force F2. During this process, the clamping force and the liquid pressure filled into the die-casting cavity increase synchronously. S6, Pressure Holding and Solidification: Maintain F2 and injection pressure to ensure complete solidification of the alloy liquid under high pressure; S7, Pressure relief and mold opening: Reverse start of the lower booster component, upper booster component, and closing component, then drive the moving mold component to slide upward to achieve mold opening; S8. Casting Ejection: Activate the ejector pin drive structure inside the moving mold to extend and retract the ejector pin to eject the formed casting; S9. Component Reset: Drive the injection unit and ejector pin to reset, completing the one-time molding process.

2. The magnesium and aluminum alloy extrusion casting process according to claim 1, characterized in that, In step S1, the mold closing assembly includes a mold closing cylinder, an electronic ruler for setting the mold closing transition position and end position, and the mold closing cylinder is hinged to the side wall of the moving mold assembly through the first hinge seat.

3. The magnesium and aluminum alloy extrusion casting process according to claim 1, characterized in that, In step S2, the closing assembly includes a closing cylinder. The closing cylinder drives the gate block to slide along the first T-shaped guide rail at the upper end of the locking wedge via a telescopic connecting rod until the locking teeth on both sides of the gate block are fully engaged with the inner tooth groove of the pull rod.

4. The magnesium and aluminum alloy extrusion casting process according to claim 1, characterized in that, In step S3, the injection unit includes an injection cylinder and a support frame that supports the injection cylinder. The injection piston rod at the output end of the injection cylinder is provided with a punch, which slides with the barrel.

5. The magnesium and aluminum alloy extrusion casting process according to claim 1, characterized in that, In step S4, the filling clamping force F1 satisfies F1=p1×A, where p1 is the filling pressure and A is the die casting projected area; the bottom of the clamping wedge is provided with a second T-shaped guide rail that slides with the first T-shaped flange, and both are inclined to achieve a linear relationship between the clamping force and the displacement of the clamping wedge. During the filling and clamping process, filling and clamping are carried out synchronously. Before the filling is completely finished, the upper pressure component reaches the clamping force F1.

6. The magnesium and aluminum alloy extrusion casting process according to claim 1, characterized in that, In step S5, the extrusion clamping force F2 satisfies F2=p2×A, where p2 is the extrusion pressure and A is the die-casting projected area; the lower pressurization component includes a pressurization cylinder and a pressurization wedge. The pressurization wedge slides along the pressurization wedge block of the support frame, pushing the injection cylinder to slide along the support frame to increase the extrusion force of the injection piston rod, and extrusion injection begins. The clamping force and the extrusion injection force increase synchronously, so that the extrusion force and the clamping force cancel each other out.

7. The magnesium and aluminum alloy extrusion casting process according to claim 1, characterized in that, In step S6, the holding time is set according to the wall thickness of the casting.

8. The magnesium and aluminum alloy extrusion casting process according to claim 1, characterized in that, In step S7, the pressure relief and mold opening sequence is as follows: first release the extrusion pressure of the injection cylinder, then release the extrusion clamping force F2, and continue to reverse the start of the clamping assembly to achieve high-pressure mold opening. After the high-pressure mold opening distance is 2~5mm, release the brake, and finally drive the moving mold assembly to slide up quickly. The mold opening distance ensures that the assembly can be removed.

9. The magnesium and aluminum alloy extrusion casting process according to claim 1, characterized in that, In step S8, the moving mold includes a moving mold frame connected to the moving mold plate, the lower end of the moving mold frame is connected to the upper mold, the ejector pin is set in the upper mold, and the ejector pin drive structure drives the ejector pin to extend and retract downward to eject the casting.

10. The magnesium and aluminum alloy extrusion casting process according to claim 1, characterized in that, In step S9, when the component is reset, the injection cylinder is activated to drive the injection piston rod to reset the punch downward along the barrel, and the ejector pin drive structure is activated simultaneously to reset the ejector pin upward.

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