Solid-phase additive double-screw stirring and extruding device and method
By designing a twin-screw mixing and extrusion device, the problems of discontinuous feeding, material blockage, and inaccurate heat control in solid-phase additive manufacturing were solved, enabling multi-material mixing and efficient deposition, thereby improving manufacturing efficiency and quality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIJING UNIV OF TECH
- Filing Date
- 2025-11-19
- Publication Date
- 2026-04-21
AI Technical Summary
Existing solid-phase additive manufacturing equipment suffers from problems such as discontinuous feeding, low material utilization, frequent material blockage, inaccurate heat control, and difficulty in mixing multiple materials, resulting in low deposition efficiency and poor quality.
The device employs a twin-screw mixing and extrusion unit, including first and second screws, a segmented barrel, electromagnetic induction heating, and a cold liquid channel, to achieve precise preheating, cooling, and multi-material mixing of materials, supporting the conveying and in-situ uniform mixing of materials in various forms.
It improves the efficiency and quality of additive manufacturing, expands the range of material applications, reduces energy consumption and maintenance costs, and ensures stable extrusion volume and material plasticization effect.
Smart Images
Figure CN121893528A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of solid-state stirring friction additive manufacturing technology, and specifically relates to a solid-phase additive twin-screw stirring and extrusion device and method. Background Technology
[0002] Solid-state additive manufacturing technology, as an emerging international cutting-edge technology, can effectively avoid defects caused by the melting and solidification of metal materials (such as cracks, pores, and coarse grains), providing an advanced solution for the efficient, integrated, high-quality, and low-cost manufacturing of lightweight, high-strength alloy structural components, and has great development potential in the field of high-end manufacturing.
[0003] Traditional solid-phase additive manufacturing primarily uses plates and rods as raw materials. However, due to drawbacks such as discontinuous feeding and large structural dimensions, it suffers from low material utilization and deposition efficiency, excessive interface connections, and difficulty in depositing complex components. Continuous filament feeding can solve these problems. Specifically, existing solid-phase additive manufacturing equipment mainly uses a single screw for continuous filament feeding, ensuring the continuity of additive deposition.
[0004] However, single-screw continuous feeders have relatively low extrusion force, lack self-cleaning capabilities, and cannot transport materials with high friction coefficients or high viscosity after plasticization. They are also prone to material blockage. During extrusion, the material is easily compacted into blocks, causing blockage and creating a reaction force on the rotating screw, resulting in uneven torque that can lead to screw stall and premature failure. Furthermore, single-screw feeding relies primarily on the friction of the screw for transport. While the material undergoes axial displacement due to compression from the screw threads within the screw channels, the lack of a backward thrust results in poor forward conveying capacity. The material's residence time in the barrel is long and varies across different parts, leading to unstable extrusion rates.
[0005] During material transport using a single screw, the heat generation between the material and the screw, and between the material and the inner wall of the barrel, is limited, resulting in very limited plasticizing effect on the material. External heating devices are needed to enhance preheating and improve the plastic flow of the material, such as electromagnetic induction heating coils. If too few external heating devices are installed, the limited heat generation leads to poor plasticizing and weak plastic flow, thus affecting the deposition quality. Conversely, while too many external heating devices ensure sufficient heat supply and are beneficial to the plasticizing and deposition of metal materials to some extent, excessive heat is transferred to the feed port, causing premature melting and plasticization of the material at the feed port, blocking it and affecting feeding. Furthermore, existing solid-state additive manufacturing equipment's feeding devices do not consider precise preheating and cooling, resulting in significant energy and material waste. They also suffer from problems such as material blockage at the discharge port and excessively high plasticizing material temperatures, leading to low additive forming efficiency and poor deposition quality.
[0006] Furthermore, existing solid-state additive manufacturing equipment typically employs a single-channel feeding design, supporting only the transport and deposition of materials in a single morphology (filaments). On one hand, not all materials can be fabricated into filaments, thus limiting the application range of raw materials through single-morphology feeding. On the other hand, with the development of novel composite materials such as metal-based / ceramic-based composites and graded functional materials, there is an urgent need for a feeding device capable of dynamically controlling the proportions of two or more metal / non-metal materials, achieving in-situ uniform mixing, and enabling gradient transitions, in order to additively deposit components with higher strength, quality, and performance. Therefore, developing a feeding device that supports the coordinated transport and in-situ mixing of multiple materials and morphologies is crucial for the development and application of high-performance composite materials in solid-state additive manufacturing. Summary of the Invention
[0007] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a solid-phase additive manufacturing twin-screw mixing and extrusion device and method. This invention effectively solves the problems of material blockage and unstable extrusion volume during continuous feeding with a single screw, and enables precise preheating and cooling, significantly improving additive manufacturing efficiency and deposition quality while saving energy. Furthermore, this invention supports the simultaneous delivery and in-situ uniform mixing of one or more material morphologies to meet the development and application needs of high-performance composite materials in solid-phase additive manufacturing.
[0008] To achieve the above objectives, the present invention provides the following technical solution: A solid-phase additive twin-screw mixing and extrusion device includes a first drive assembly, a transmission device, a fixed connecting seat, a twin-screw assembly, and a second drive assembly; the twin-screw assembly includes a first screw, a second screw, a barrel, a die head, a slewing bearing, a mixing head, a discharge port, an electromagnetic induction heating coil, a cold liquid channel, a liquid inlet, a liquid outlet, a feeding port, and a temperature sensor; The first drive assembly is connected to the twin-screw assembly via a transmission device; the top of the fixed connecting seat is detachably mounted to the bottom of the transmission device; the first screw and the second screw are arranged parallel to each other inside the barrel; the top of the barrel is detachably mounted to the bottom of the fixed connecting seat, and the top of the head is detachably mounted to the bottom of the barrel; the top of the slewing bearing is detachably mounted to the bottom of the head; the top of the stirring head is detachably mounted to the bottom of the slewing bearing; a discharge hole of a certain shape is machined in the center of the stirring head; the electromagnetic induction heating coil is wound around the outer wall of the barrel; the... The coolant channels are respectively machined and installed inside the barrel wall near the top and bottom of the barrel. Each coolant channel is connected to a coolant inlet and a coolant outlet. The coolant inlet is located on the side near the top of the barrel and connects to the coolant channel. The coolant outlet is located on the side near the bottom of the barrel and connects to the coolant channel. The feed hole is located on the side near the top of the barrel and extends through to the inner wall of the barrel. The feed hole guides the material tangentially into the screw groove. The temperature sensor is fixedly embedded in the temperature measuring area of the inner wall of the barrel. The second drive assembly is connected to the slewing bearing through gear meshing to transmit power.
[0009] Furthermore, the thread direction of the first screw and the thread direction of the second screw are set in the same direction, the first screw and the second screw rotate in parallel and in the same direction, the thread groove of the first screw and the thread ridge of the second screw mesh with each other, there is a meshing gap between the thread groove of the first screw and the thread ridge of the second screw, and there is a certain gap between the top of the thread ridge of the screw and the inner wall of the barrel to avoid direct contact of the threads and scratching the inner wall of the barrel.
[0010] Further, the transmission device includes a transmission housing, a drive gear shaft, a first driven gear shaft, a second driven gear shaft, a first connecting ring, and a second connecting ring. The drive gear shaft, the first driven gear shaft, and the second driven gear shaft are respectively fixedly installed in the transmission housing by coaxially arranged bearings and end covers. The drive gear shaft is connected to the driven gears coaxially positioned on the first and second driven gear shafts by two coaxially positioned drive gears to transmit power. The end faces of the first and second driven gear shafts near the twin-screw assembly are located on the same plane. The end faces of the first and second driven gear shafts near the twin-screw assembly and the end faces of the first and second screws near the transmission device are aligned and coaxially fitted. The first connecting ring connects the end face of the first driven gear shaft near the twin-screw assembly and the end face of the first screw near the transmission device via a keyway. The second connecting ring connects the end face of the second driven gear shaft near the twin-screw assembly and the end face of the second screw near the transmission device via a keyway.
[0011] Furthermore, the second drive assembly includes a second driver, a gear, and a positioning block; the gear is fixedly mounted on the second driver; the positioning block is fixedly mounted on the end face of the gear near the stirring head, and the gear and the slewing bearing mesh with each other to transmit power.
[0012] Furthermore, the inner wall of the die head is designed to be inclined to prevent the plastic material from accumulating in the cavity and to guide the plastic material to be extruded towards the discharge hole.
[0013] Furthermore, the bottom of the stirring head is machined with protrusions around the center of the discharge hole, which are distributed in a circumferential array, radially, uniformly, or symmetrically.
[0014] Furthermore, the barrel is a segmented barrel, including a feeding section barrel, a plasticizing section barrel, a mixing section barrel, an exhaust section barrel, and a metering section barrel; the top of the feeding section barrel is detachably installed on the bottom of the fixed connecting seat; the top of the plasticizing section barrel is detachably installed on the bottom of the feeding section barrel; the top of the mixing section barrel is detachably installed on the bottom of the plasticizing section barrel; the top of the exhaust section barrel is detachably installed on the bottom of the mixing section barrel; the top of the metering section barrel is detachably installed on the bottom of the exhaust section barrel; and the top of the die head is detachably installed on the bottom of the metering section barrel.
[0015] Furthermore, the feeding hole is machined on the side near the top of the feeding section barrel and extends to the inner wall of the barrel. Cooling liquid channels are machined inside the walls of the feeding section barrel and the metering section barrel. Each cooling liquid channel is connected to an inlet hole and an outlet hole. The inlet hole is located on the side near the top of the barrel in the feeding section barrel and the metering section barrel and connects to the cooling liquid channel. The outlet hole is located on the side near the bottom of the barrel in the feeding section barrel and the metering section barrel and connects to the cooling liquid channel. The vent hole is located on the side near the bottom of the barrel in the venting section barrel and extends to the inner wall of the barrel. A breathable membrane is fixedly installed on the side of the vent hole near the inner wall of the venting section barrel, or it is connected to an automatic vent valve or a vacuum pump. The electromagnetic induction heating coil is wound around the outer wall of the plasticizing section barrel and the mixing section barrel. The temperature sensor is fixedly embedded in the inner wall of the feeding section barrel, the metering section barrel, the plasticizing section barrel, and the mixing section barrel.
[0016] Furthermore, the first screw and the second screw are combined screws, including conveying elements, mixing elements, other special functional elements, mandrels, and screw head nuts of different sizes and specifications. Each screw element is circumferentially fixed to the screw mandrel by a keyway of a specific shape. Each screw element and the end of the screw mandrel near the connecting ring are axially positioned by a shoulder. The screw head nut is fixed to the other end of the screw mandrel by a threaded engagement.
[0017] A method for a solid-phase additive twin-screw mixing and extrusion apparatus includes the following steps: Step 1: Based on the material properties and process requirements used in additive manufacturing, select appropriate barrel and screw components to combine, assemble the complete twin-screw mixing and extrusion device, and fix it to the first drive device, and connect the power supply to each working component; Step 2: Obtain the data of the workpiece to be processed through modeling or scanning, and compile the corresponding CNC code; Step 3: Prepare the raw materials required for additive manufacturing, load them into the corresponding feeder, and feed one or more types of materials into one or more corresponding feed holes. Check and debug the equipment. Step 4: Fix the prepared work substrate onto the worktable; Step 5: Control the twin-screw mixing and extrusion device to move to the starting position of the matrix to be additively manufactured area; Step 6: The feeder begins to continuously feed material into the feed hole. Simultaneously, the first drive unit drives the transmission device in the twin-screw mixing and extrusion unit. Power is transmitted from the transmission device to the twin screws, which rotate at a certain speed to convey, crush, compress, and shear the fed material. At the same time, the electromagnetic induction heating coil and the cold liquid channel begin to operate. Simultaneously, the second drive unit drives the slewing bearing to rotate, which in turn drives the mixing head to begin rotating at a certain speed. Step 7: Control the movement of the twin-screw agitator and extruder to ensure that the rotating agitator head shoulder is at a suitable distance from the substrate surface (or the surface of the previous deposited layer), allowing space for the additive layer. At this time, a portion of the agitator head protrusion penetrates into the substrate (or the interior of the previous deposited layer) to generate heat through agitation and friction, thus beginning to plasticize the substrate surface (or the surface of the previous deposited layer). Step 8: As the twin-screw assembly continues to rotate, extrude, and convey, new plasticized material is extruded from the discharge port and flows along the space between the agitator shoulder and the substrate surface (or the surface of the previous deposited layer). Simultaneously, under the continuous rotation and friction of the agitator and protrusions, the new plasticized material and the substrate surface material (or the previous deposited surface material plasticized by the agitator friction) mix together, undergoing metallurgical bonding and dynamic recrystallization to form an additive deposition layer of a certain height. Step 9: As the twin-screw agitator and extruder move continuously in the additive manufacturing zone, the first additive layer is obtained. If multiple additive layers need to be printed, after completing the first additive layer, control the twin-screw agitator and extruder to raise it to a certain height and position it to the next starting position. Repeat steps 6, 7, and 8 to achieve continuous solid-state additive manufacturing, avoid errors caused by re-clamping, and improve additive manufacturing efficiency.
[0018] Compared with the prior art, the present invention has the following technical effects: 1. Utilizing a twin-screw extrusion structure, compared to a single-screw extrusion, it boasts greater extrusion and shear forces, resulting in superior material compression and plasticization. Furthermore, the interlocking and scraping of the screw channels and edges of the two screws mechanically clean the screw surface, providing excellent self-cleaning capabilities. This effectively prevents reverse torque on the screws caused by material being compressed into blocks, thus avoiding material blockage and jamming, preventing premature screw failure that could impact the entire additive manufacturing process, and reducing maintenance costs. In addition, the twin-screw extrusion structure can transport materials with high viscosity or high surface friction coefficients. It is not limited to compressing and plasticizing materials in only one form, such as filaments; it can also plasticize powders, granules, and even plasticize and mix materials of various forms and types, effectively expanding the application forms and types of raw materials while ensuring stable extrusion rates. 2. Employing a twin-screw extrusion structure, it can be equipped with one or more feeding orifices to achieve simultaneous conveying and uniform mixing of one or more materials of the same form, or simultaneously conveying and uniformly mixing one or more materials of different forms. Through multi-material synergistic conveying, dynamic proportioning control, in-situ uniform mixing, and gradient transition of multiple materials can be achieved, thereby additively depositing novel composite components with higher strength, higher quality, and higher performance. 3. A segmented barrel with different functions is designed, utilizing a coolant channel and electromagnetic induction heating coils to achieve zoned temperature control during the material plasticizing and mixing process. This enables precise preheating and cooling, ensuring good material plasticizing effects, avoiding unnecessary energy waste and feed hole blockage, and shortening the cooling time of the deposited material, thereby effectively improving the overall additive manufacturing efficiency and deposition quality. Furthermore, the segmented barrel facilitates daily cleaning, replacement, and maintenance, reducing maintenance costs.
[0019] 4. The use of a modular screw allows for flexible configuration based on the material properties and process requirements of additive manufacturing, improving the plasticizing effect and distribution, dispersion and mixing effect of one or more materials, thereby further improving the deposition quality and reducing maintenance costs; 5. Drive the feeder, twin screw assembly, and mixing head separately to decouple the feeding speed and mixing speed, thus broadening the process window. Attached Figure Description
[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.
[0021] Figure 1 This is a front view of the solid-phase additive twin-screw mixing and extrusion apparatus of the present invention; Figure 2 This is a schematic diagram of a preferred angle of the solid-phase additive twin-screw stirring and extrusion device of the present invention. Figure 3 for Figure 1 A schematic diagram of the transmission device involved in the process; Figure 4 for Figure 1 A schematic diagram of the twin-screw assembly structure involved in the process; Figure 5 for Figure 4 A schematic diagram of the internal structure of the barrel after the hidden electromagnetic induction heating coil is made transparent. Figure 6 for Figure 4 A schematic diagram of the twin-screw structure involved in the process; Figure 7 The diagram illustrates several different geometric structures and distributions of stirring head protrusions, serving as examples.
[0022] In the diagram: 10-First drive assembly, 101-First driver, 102-Coupling, 20-Transmission device, 201-Transmission housing, 202-Drive gear shaft, 203-First driven gear shaft, 204-Second driven gear shaft, 205-First connecting ring, 206-Second connecting ring, 30-Fixed connecting seat, 40-Twin screw assembly, 401-First screw, 4011-Mandrel, 4012-Feeding section screw, 4013-Plasticizing section screw, 4014-Mixing section screw, 4015-Exhaust section screw, 4016-Metering section screw, 4017-Screw head nut, 402- Second screw, 403-barrel, 4031-feeding section barrel, 4032-plasticizing section barrel, 4033-mixing section barrel, 4034-venting section barrel, 4035-metering section barrel, 404-machine head, 405-slewing bearing, 406-mixing head, 4061-protrusion, 407-discharge hole, 408-electromagnetic induction heating coil, 409-cold liquid channel, 410-liquid inlet, 411-liquid outlet, 412-feeding hole, 413-venting hole, 414-temperature sensor, 50-second drive assembly, 501-second driver, 502-gear, 503-positioning block. Detailed Implementation
[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0024] In the description of this invention, it should be understood that the terms "center," "top," "bottom," "left," "right," "vertical," "horizontal," "inner," "outer," and "back side," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.
[0025] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0026] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a solid-phase additive manufacturing twin-screw mixing and extrusion device and method. This invention effectively solves the problems of material blockage and unstable extrusion volume during continuous feeding with a single screw, and enables precise preheating and cooling, significantly improving additive manufacturing efficiency and deposition quality while saving energy. Furthermore, this invention supports the simultaneous delivery and in-situ uniform mixing of one or more material morphologies to meet the development and application needs of high-performance composite materials in solid-phase additive manufacturing.
[0027] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0028] Combined with appendix Figure 1 and attached Figure 2 As shown, the present invention provides a solid-phase additive twin-screw mixing and extrusion device, including a first drive assembly 10, a transmission device 20, a fixed connecting seat 30, a twin-screw assembly 40, and a second drive assembly 50.
[0029] The first drive assembly 10 drives the twin-screw assembly 40 through the transmission device 20. In this embodiment, the first drive assembly 10 includes a first driver 101 and a coupling 102. Those skilled in the art can select the first driver 101 and the connecting and transmission elements according to actual needs, such as through a robotic arm, electric spindle, motor, etc., or on this basis, by connecting and transmission elements to the axial end of the drive gear shaft 202 in the transmission device 20 for driving, thereby driving the twin-screw assembly 40 through the transmission device 20.
[0030] Reference for the design structure of transmission device 20 Figure 3 As shown, the transmission housing includes a drive gear shaft 201, a drive gear shaft 202, a first driven gear shaft 203, a second driven gear shaft 204, a first connecting ring 205, and a second connecting ring 206. The drive gear shaft 202, the first driven gear shaft 203, and the second driven gear shaft 204 are respectively fixedly installed in the transmission housing 201 by bearings and end caps arranged coaxially. The drive gear shaft 202 has two drive gears that are coaxially positioned and connected to the driven gears that are coaxially positioned and installed on the first driven gear shaft 203 and the second driven gear shaft 204 to transmit power, so that the first driven gear shaft 203 and the second driven gear shaft 204 rotate in the same direction and at the same speed. The end faces of the first driven gear shaft 1203 and the second driven gear shaft 204 near the twin-screw assembly 40 are located on the same plane. The end faces of the first driven gear shaft 203 and the second driven gear shaft 204 near the twin-screw assembly 40, and the end faces of the first screw 401 and the second screw 402 near the transmission device 20 are aligned and coaxially fitted. A first connecting ring 205 connects the end faces of the first driven gear shaft 203 near the twin-screw assembly 40 and the first screw 401 near the transmission device 20 via a keyway to transmit power to the first screw 401, causing it to rotate. A second connecting ring 206 connects the end faces of the second driven gear shaft 204 near the twin-screw assembly 40 and the second screw 402 near the transmission device 20 via a keyway to transmit power to the second screw 402, causing it to rotate. The first screw 401 and the second screw 402 rotate in parallel, in the same direction, and at the same speed.
[0031] The top of the fixed connecting seat 30 is detachably installed at the bottom of the transmission housing 201, and the bottom of the fixed connecting seat 30 is detachably installed with the twin screw assembly 40. The fixed connecting seat 30 connects the transmission device 20 and the twin screw assembly 40, fixes the position of the twin screw assembly 40, and ensures that the twin screw assembly 40 is sufficiently stable during mixing and extrusion operations.
[0032] Design structure reference for twin-screw assembly 40 Figure 4 and attached Figure 5As shown, the assembly includes a first screw 401, a second screw 402, a screw barrel 403, a screw head 404, a slewing bearing 405, a stirring head 406, a discharge port 407, an electromagnetic induction heating coil 408, a cold liquid channel 409, a liquid inlet 410, a liquid outlet 411, a feeding port 412, and a temperature sensor 414. The first screw 401 and the second screw 402 are arranged parallel to each other inside the barrel 403. The thread direction of the first screw 401 and the thread direction of the second screw 402 are in the same direction, and the first screw 401 and the second screw 402 rotate in parallel and in the same direction. The screw groove of one screw and the screw ridge of the other screw mesh with each other to compress and plasticize the material. There is a meshing gap between the screw groove of one screw and the screw ridge of the other screw. The material is subjected to strong shearing, stirring, and friction in the meshing gap, so the plasticizing effect is relatively good. The rotating extrusion of a twin-screw extruder allows material to be transferred and conveyed between the screws, advancing in an "∞" shape. This conveying method is called positive displacement conveying, also known as forced conveying. It can convey materials with high viscosity and high friction coefficients between metal surfaces. Compared to single-screw extrusion feeding, twin-screw feeding broadens the range of raw material selection. Twin-screws have greater extrusion and shear forces than single-screws, resulting in better material compression and plasticization. The interlocking and scraping of the screw channels and edges of the two screws mechanically clean the screw surfaces, providing excellent self-cleaning capabilities. This also effectively prevents the material from generating reverse torque on the screws due to being compressed into blocks, thus effectively avoiding material blockage and jamming. Premature screw failure can also affect the entire additive manufacturing process and reduce maintenance costs. Furthermore, it is not limited to plasticizing filaments; it can also plasticize powders and granules, expanding the application forms and types of raw materials while ensuring a stable extrusion volume.
[0033] Twin-screw extruders are mainly classified into parallel co-directional twin-screw extruders, meshing counter-directional twin-screw extruders, and non-meshing counter-directional twin-screw extruders. Parallel co-directional twin-screw extruders allow for material exchange and offer advantages such as high conveying efficiency, strong mixing capacity, good self-cleaning properties, and uniform material residence time distribution. During design, it is important to ensure that the groove width in the axial direction of the meshing area of the two screws is greater than the width of the screw ridges. Furthermore, a certain gap exists between the top of the screw ridges and the inner wall of the barrel 403 to prevent direct contact and scratching of the inner wall of the barrel 403. This also allows for further shearing, friction, and plasticization between the material and the screw ridges, and between the material and the inner wall of the barrel 403.
[0034] The top of the barrel 403 is detachably mounted to the bottom of the fixed connecting seat 30 to secure the entire twin-screw assembly 40. The top of the die head 404 is detachably mounted to the bottom of the barrel 403 to accommodate the plasticized metal material. The top of the slewing bearing 405 is detachably fixed to the bottom of the die head 404, and the top of the stirring head 406 is detachably mounted to the bottom of the slewing bearing 405. The second drive 501 drives the gear 502, which meshes with the slewing bearing 405 to transmit power, thereby causing the slewing bearing 405 to rotate the stirring head 406. The detachable mounting of the stirring head 406 and the slewing bearing 405 allows for flexible replacement of different sizes and types of stirring heads 406 according to actual manufacturing needs, achieving high-quality and efficient deposition. The stirring head 406 has a discharge hole 407 of a specific shape machined in its center, through which the plasticized material is discharged for deposition. The detachable connection facilitates inspection, cleaning, maintenance, and replacement of components, reducing maintenance costs and improving processing flexibility.
[0035] The electromagnetic induction heating coil 408 is wound around the outer wall of the barrel 403. The electromagnetic induction heating coil 408 achieves heating based on the Faraday electromagnetic induction principle. It has a short preheating time, high thermal efficiency, and uniform heating. It can provide sufficient heat for the plasticizing material, ensuring uniform preheating, sufficient plasticization, and stable output, thereby improving deposition quality and ensuring production efficiency.
[0036] Cooling channels 409 are machined and installed inside the barrel wall near the top and bottom of the barrel 403. Regardless of whether an electromagnetic induction heating coil 408 is added, shear heat, frictional heat, and plastic deformation heat will be generated between the material and the twin screw, and between the material and the inner wall of the barrel 403. This accumulated heat is transferred to the feed hole 412, causing the material at the feed hole 412 to melt and plasticize prematurely, blocking the feed hole 412 and affecting subsequent material conveying. Therefore, it is necessary to remove this heat as much as possible in the feeding section to reduce the temperature at the feed hole 412. In addition, the addition of cooling channels 409 inside the barrel wall of the barrel 403 near the discharge hole 407 can cool the plasticized material, thereby reducing the material solidification time and improving deposition efficiency and quality. One coolant channel 409 is connected to one inlet hole 410 and one outlet hole 411. The inlet hole 410 is machined on the side near the top of the barrel 403 and is connected to the coolant channel 409. The outlet hole 411 is located on the side near the bottom of the barrel 403 and is connected to the coolant channel 409. The coolant first enters the coolant channel 409 from the inlet hole 410, absorbs the transferred heat, reduces the temperature of the barrel 403, and then flows out from the outlet hole 411 and circulates for cooling, further improving the cooling effect.
[0037] The coolant has the lowest temperature and strongest heat absorption capacity when it enters through the inlet hole 410, resulting in the best cooling effect around the feed hole 412. As the coolant flows downwards along the coolant channel 409 under gravity, it continuously absorbs heat, and the cooling effect decreases. Finally, it is discharged from the outlet hole 411. This cyclical cooling method ensures the continuity, stability, and effectiveness of the cooling process. Those skilled in the art can select a suitable coolant according to actual needs, such as oil cooling or water cooling.
[0038] Temperature sensor 414 is fixedly embedded in the temperature measuring point on the inner wall of barrel 403, and works in conjunction with electromagnetic induction heating coil 408 and cold liquid channel 409 to achieve precise preheating and cooling.
[0039] The feeding hole 412 is located on the side near the top of the barrel 403 and extends through the inner wall of the barrel 403. The feeding hole 412 guides the material tangentially into the screw groove of one screw. As the twin screws rotate, the material is conveyed by the rotational friction between the screw groove and the inner wall of the barrel 403, as well as the frictional compression between the screw groove of one screw and the corresponding screw edge of the other screw. The tangential force generated by the screw groove and screw edge on the material causes the material to move downward. This invention supports the continuous conveying and deposition of filaments, granules, and powders, expanding the range of materials that can be selected. Those skilled in the art can set the specific number of feeding holes 412 according to actual needs, such as one, two, three, etc. In addition, the aperture size of the feeding holes 412 can also be adjusted to adapt to different sizes of filaments, granules, powders, etc., which will not be elaborated further. Those skilled in the art can set the specific method of material conveying to the feeding hole 412 according to actual needs, such as through a filament feeder, powder feeder, etc., which will not be elaborated further.
[0040] The inner wall of the die head 404 is inclined, and the diameter decreases from large to small. This can effectively increase the extrusion pressure of the plastic material, prevent the plastic material from accumulating in the cavity, and guide the plastic material to be extruded towards the discharge hole 407.
[0041] The bottom of the stirring head 406 has protrusions 4061 machined around the center of the discharge hole 407, which are distributed in a circumferential array, radially, uniformly, or symmetrically. The stirring head 406 rotates around its axis, and the shoulder of the rotating stirring head 406 has a suitable gap from the surface of the substrate or the surface of the previous deposited layer, leaving space for the additive deposition layer. At this time, part of the protrusions 4061 penetrates into the interior of the substrate or the interior of the previous deposited layer to generate heat through stirring friction. The surface material of the substrate or the surface material of the previous deposited layer is plasticized under the action of stirring friction. At the same time, the new plasticized material flows out from the discharge hole 407 of the stirring head 406. The new plasticized material and the surface material of the substrate or the surface material of the previous deposited layer that has been plasticized by the stirring friction of the protrusions 4061 mix with each other, and metallurgical bonding and dynamic recrystallization occur to form an additive layer. The protrusions 4061 facilitate a more uniform mixing of the new plasticizing material and the substrate surface material after being friction-plasticized by the protrusions 4061, or the previously deposited surface material after being friction-plasticized by the protrusions 4061. This also promotes grain refinement, enhances interlayer bonding and stability, thereby improving molding quality and production efficiency. Those skilled in the art can design the geometry and distribution of the protrusions 4061 according to actual needs, and are not limited to the arrangement shown in the appendix. Figure 7 As shown.
[0042] The second drive assembly 50 includes a second driver 501, a gear 502, and a positioning block 503. The gear is fixedly mounted on the second driver 501, and the positioning block 503 is fixedly mounted on the end face of the gear 502 near the stirring head 406, holding and positioning the gear 502. The gear 502 and the slewing bearing 405 mesh with each other to transmit driving force. Those skilled in the art can select the second driver 501 according to actual needs, such as a motor.
[0043] As attached Figure 4 As shown, the barrel 403 is a segmented barrel, including a feeding section barrel 4031, a plasticizing section barrel 4032, a mixing section barrel 4033, an exhaust section barrel 4034, and a metering section barrel 4035. The top of the feeding section barrel 4031 is detachably installed at the bottom of the fixed connecting seat 30. The top of the plasticizing section barrel 4032 is detachably installed at the bottom of the feeding section barrel 4031. The top of the mixing section barrel 4033 is detachably installed at the bottom of the plasticizing section barrel 4032. The top of the exhaust section barrel 4034 is detachably installed at the bottom of the mixing section barrel 4033. The top of the metering section barrel 4035 is detachably installed at the bottom of the exhaust section barrel 4034. The top of the head 404 is detachably installed at the bottom of the metering section barrel 4035. The detachable barrel 403 is easier to clean, inspect, repair, and replace, which is beneficial for flexibly combining barrels of different functional sections according to actual needs and reducing maintenance costs. The feeding hole 412 is machined on the side near the top of the feeding section barrel 4031 and extends through to the inner wall of the barrel.
[0044] As attached Figure 5 As shown, cooling channels 409 are machined inside the walls of the feeding section barrel 4031 and the metering section barrel 4035 to achieve precise cooling. On the one hand, regardless of whether an electromagnetic induction heating coil 408 is added, shear heat, frictional heat, and plastic deformation heat will be generated between the material and the twin screws, and between the material and the inner wall of the barrel. This heat will accumulate and be transferred to the feeding hole 412, causing the material at the feeding hole 412 to melt and plasticize prematurely, blocking the feeding hole 412 and affecting the subsequent material conveying. Therefore, it is necessary to remove and reduce the heat transferred to the feeding hole 412 as much as possible in the feeding section. On the other hand, adding cooling channels 409 inside the wall of the metering section barrel 4035 can reduce the temperature of the plasticized material in advance, thereby reducing the material solidification time and improving the efficiency and quality of deposition molding. In addition, a cold liquid channel 409 is connected to a liquid inlet 410 and a liquid outlet 411. The liquid inlet 410 is located inside the wall of the feeding section barrel 4031 and the metering section barrel 4035 near the top of the barrel and is connected to the cold liquid channel 409. The liquid outlet 411 is located inside the wall of the feeding section barrel 4031 and the metering section barrel 4035 near the bottom of the barrel and is connected to the cold liquid channel 409.
[0045] The coolant enters the cooling channel 409 through the inlet port 410, absorbing the transferred heat. At this point, the coolant temperature is at its lowest, its heat absorption capacity is at its strongest, and the cooling effect around the feed port 412 is optimal. As the coolant flows downwards along the cooling channel 409 under gravity, it gradually absorbs heat from the barrel 403, and the cooling effect weakens. Finally, it is discharged through the outlet port 411, thus completing the cyclic cooling process and ensuring its continuity, stability, and effectiveness. Those skilled in the art can select a suitable coolant, such as oil cooling or water cooling, according to actual needs.
[0046] The vent 413 is located on the side of the barrel 4034 in the venting section, near the bottom of the barrel, and extends through to the inner wall of the barrel. The vent 413 is fixedly installed with a breathable membrane or connected to an automatic vent valve or a vacuum pumping device on the side near the inner wall of the barrel, so that the air in the plasticized material is squeezed out and the material is not leaked. Squeezing out the air in the plasticized material is beneficial to further improve the forming quality and strength of the additive parts.
[0047] Electromagnetic induction heating coils 408 are wound around the outer walls of the plasticizing section barrel 4032 and the mixing section barrel 4033 to achieve precise preheating. The induction heating coils provide sufficient heat to the material inside the barrels, accelerating plasticization, improving plastic flowability, and thus increasing continuous feeding efficiency and production efficiency. Furthermore, temperature sensors 414 are fixedly embedded in the inner walls of the feeding section barrel 4031, the metering section barrel 4035, the plasticizing section barrel 4032, and the mixing section barrel 4033 to achieve precise temperature control in each section.
[0048] As attached Figure 6 As shown, the first screw 401 and the second screw 402 are combined screws, including various functional components such as conveying elements, mixing elements, and blending elements of different sizes and specifications, as well as a mandrel 4011 and a screw head nut 4017. The screw elements with different functions repeatedly perform shearing, extrusion, friction, stretching, and displacement operations on the material, causing changes in the particle size and position of the material, achieving the distribution and dispersion mixing of one or more materials. Those skilled in the art can design or select the structure and size of each functional component and flexibly combine them according to actual needs, which will not be elaborated further.
[0049] Conveying elements are divided into forward threaded elements and reverse threaded elements. Forward threaded elements convey material in the same direction as the extrusion direction, resulting in excellent conveying and mixing effects. Reverse threaded elements convey material in the opposite direction to the extrusion direction, conveying it forward through a leakage mechanism. Reverse threaded elements are mainly placed upstream of the venting section, serving to build pressure, promote plasticization, and enhance mixing. Threaded elements are available in single-start, double-start, and triple-start configurations, and the screw groove shape can be formed based on the screw geometry. To achieve the compression and plasticization of the material, the lead of the threaded element varies from the feeding section to the metering section. In the feeding and venting sections, elements with large lead are required to facilitate feeding and venting.
[0050] Mixing elements can be meshing blocks. Kneading disc elements, also known as shearing elements, provide high shear strength and good dispersion and distribution mixing capabilities, which is beneficial for the uniform dispersion and distribution mixing of various materials. The outer contour shape of the kneading disc is derived from the geometry of a twin-screw extruder. Several kneading discs are connected in series to form a meshing block, and its performance is determined by the number of kneading discs, the axial length of the meshing block, and the stagger angle between adjacent discs. In addition, threaded elements that can provide strong shear force can also be used as mixing elements to shear and crush large particles, achieving uniform dispersion and mixing. Threaded elements that can generate a large backflow can also be used as mixing elements, where the reverse flow and forward flow are mixed, and the various materials at the interface are repeatedly mixed and replaced, achieving a better distribution mixing effect.
[0051] The main mixing elements are SME, TME, and ZME. SME is a threaded mixing element, its structure consisting of grooves on the threaded edges of the forward conveying element, allowing for more thorough material exchange between adjacent grooves, resulting in a better mixing effect than conveying elements. TME is a turbine-type mixing element. ZME is a toothed mixing element, with grooves on the reverse conveying element, similar to SME, but it also has reverse conveying capability and stronger pressure-building capacity than SME.
[0052] Just as a segmented barrel has a feeding section, plasticizing section, mixing section, venting section, and metering section, a combined screw can also be divided into a feeding section, plasticizing section, mixing section, venting section, and metering section.
[0053] The function of the screw 4012 in the feeding section is to receive material from the feeding hole 412, and to convey, crush, compress, and shear the material. Therefore, initially, a large-lead positive thread element can be used in the feeding section to quickly convey the material without accumulating at the feeding hole 412. As the material moves towards the plasticizing section, the lead of the positive thread element gradually decreases, gradually compressing and shearing the material, thus compacting it and preparing it for further preheating and plasticizing in the plasticizing section.
[0054] The main function of the plasticizing section screw 4013 is to further crush, compress, and shear the material conveyed in the feeding section, and to preheat it with the help of the electromagnetic induction heating coil 408 to accelerate the plasticization of the material. There are two heat sources for material plasticization: one is the external heat provided by the electromagnetic induction heating coil 408, and the other is the shear heat, frictional heat, and plastic deformation heat generated by the rotation of the twin screws shearing the material. The plasticizing section can use a small-lead positive screw element to ensure the pressure and residence time required for material plasticization, which is beneficial for uniform heating and compression plasticization of the material.
[0055] The function of the 4014 screw in the mixing section is to refine and deform the plasticized material in terms of size, and to uniformly mix multiple materials. The mixing section typically uses mixing elements to distribute and disperse one or more plasticized materials for uniform mixing. The use of interlocking blocks can extend the residence time of the material in the twin-screw extruder, enhancing mixing.
[0056] The venting section screw 4015 receives material from the mixing section, along with air introduced from the feeding section. At this point, the material is relatively dense, without large cavities, making it the optimal state for venting. The front end of the venting section typically uses a forward threaded element with a large lead to reduce the filling density of the plasticized material. Immediately afterwards, a reverse threaded element or a reverse meshing block is used to establish high pressure on the plasticized material for venting. The extruded gas is discharged through the vent hole 413. The vent hole 413 is located on the side near the bottom of the venting section barrel 4034.
[0057] The metering section screw 4016 needs to establish a certain pressure so that the plasticized material can be smoothly and steadily extruded from the discharge port 407 along the inner wall of the die head 404. Therefore, the metering section often uses the method of gradually reducing the lead of the forward screw element to extrude the plasticized material.
[0058] Different functional components are flexibly combined according to actual manufacturing needs and material properties. Each component is fixed to the screw mandrel 4011 by a keyway of a specific shape to prevent the screw components from sliding circumferentially relative to the screw mandrel 4011. The end of each screw component near the connecting ring of the screw mandrel 4011 is axially positioned by a shoulder. The screw head nut 4017 is fixed to the bottom of the screw mandrel 4011 by a threaded engagement to prevent the screw components from sliding axially.
[0059] A method for a solid-phase additive twin-screw mixing and extrusion apparatus includes the following steps: Step 1: Based on the material properties and process requirements used in additive manufacturing, select appropriate barrel and screw components to combine, assemble the complete twin-screw mixing and extrusion device, and fix it to the first drive device, and connect the power supply to each working component; Step 2: Obtain the data of the workpiece to be processed through modeling or scanning, and compile the corresponding CNC code; Step 3: Prepare the raw materials required for additive manufacturing, load them into the corresponding feeder, and feed one or more types of materials into one or more feed holes 412. Check and debug the equipment. Step 4: Fix the prepared work substrate onto the worktable; Step 5: Control the twin-screw mixing and extrusion device to move to the starting position of the matrix to be additively manufactured area; Step 6: The feeder begins to continuously feed material into the feed hole 412. Simultaneously, the first drive unit drives the transmission device 20 in the twin-screw mixing and extrusion device. Power is transmitted from the transmission device 20 to the twin screw, which rotates at a certain speed to convey, crush, compress, and shear the fed material. Simultaneously, the electromagnetic induction heating coil 408 and the cold liquid channel 409 begin to operate. Simultaneously, the second drive unit drives the slewing bearing 405 to rotate, thereby driving the mixing head 406 to begin rotating at a certain speed. Step 7: Control the movement of the twin-screw agitator and extruder so that the shoulder of the rotating agitator head 406 is at a suitable distance from the surface of the substrate or the surface of the previous deposited layer, leaving space for the additive layer. At this time, a portion of the protrusion 4061 of the agitator head 406 penetrates into the interior of the substrate or the interior of the previous deposited layer to generate heat through agitation and friction, thus beginning to plasticize the surface of the substrate or the surface of the previous deposited layer. Step 8: As the twin-screw assembly 40 continuously rotates, extrudes, and conveys, new plasticized material is extruded from the discharge port 407 and flows along the space between the shoulder of the stirring head 406 and the surface of the substrate or the surface of the previous deposited layer. Simultaneously, under the continuous rotation and stirring friction of the stirring head 406 and the protrusion 4061, the new plasticized material and the substrate surface material plasticized by stirring friction or the previous deposited surface material plasticized by the protrusion 4061 mix together, undergoing metallurgical bonding and dynamic recrystallization to form an additive deposition layer with a certain height. Step 9: As the twin-screw agitator and extruder move continuously in the additive manufacturing zone, the first additive layer is obtained. If multiple additive layers need to be printed, after completing the first additive layer, control the twin-screw agitator and extruder to raise it to a certain height and position it to the next starting position. Repeat steps 6, 7, and 8 to achieve continuous solid-state additive manufacturing, avoid errors caused by re-clamping, and improve additive manufacturing efficiency.
[0060] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.
Claims
1. A solid-phase additive twin-screw mixing and extrusion device, characterized in that, It includes a first drive assembly, a transmission device, a fixed connecting seat, a twin-screw assembly, and a second drive assembly; the twin-screw assembly includes a first screw, a second screw, a barrel, a die head, a slewing bearing, a stirring head, a discharge port, an electromagnetic induction heating coil, a cold liquid channel, a liquid inlet, a liquid outlet, a feeding port, and a temperature sensor; The first drive assembly is connected to the twin-screw assembly via a transmission device; the top of the fixed connecting seat is detachably mounted to the bottom of the transmission device; the first screw and the second screw are arranged parallel to each other inside the barrel; the top of the barrel is detachably mounted to the bottom of the fixed connecting seat, and the top of the head is detachably mounted to the bottom of the barrel; the top of the slewing bearing is detachably mounted to the bottom of the head; the top of the stirring head is detachably mounted to the bottom of the slewing bearing; a discharge hole of a certain shape is machined in the center of the stirring head; the electromagnetic induction heating coil is wound around the outer wall of the barrel; the... The coolant channels are respectively machined and installed inside the barrel wall near the top and bottom of the barrel. Each coolant channel is connected to a coolant inlet and a coolant outlet. The coolant inlet is located on the side near the top of the barrel and connects to the coolant channel. The coolant outlet is located on the side near the bottom of the barrel and connects to the coolant channel. The feed hole is located on the side near the top of the barrel and extends through to the inner wall of the barrel. The feed hole guides the material tangentially into the screw groove. The temperature sensor is fixedly embedded in the temperature measuring area of the inner wall of the barrel. The second drive assembly is connected to the slewing bearing through gear meshing to transmit power.
2. The solid-phase additive twin-screw mixing and extrusion apparatus according to claim 1, characterized in that, The thread direction of the first screw and the thread direction of the second screw are set in the same direction. The first screw and the second screw rotate in parallel and in the same direction. The screw groove of the first screw and the screw ridge of the second screw mesh with each other. There is a meshing gap between the screw groove of the first screw and the screw ridge of the second screw. There is a certain gap between the top of the screw ridge and the inner wall of the barrel.
3. The solid-phase additive twin-screw mixing and extrusion apparatus according to claim 2, characterized in that, The transmission device includes a transmission housing, a drive gear shaft, a first driven gear shaft, a second driven gear shaft, a first connecting ring, and a second connecting ring. The drive gear shaft, the first driven gear shaft, and the second driven gear shaft are respectively fixedly installed in the transmission housing by bearings and end caps arranged coaxially. The drive gear shaft is connected to the driven gears arranged coaxially on the first and second driven gear shafts by two coaxially positioned drive gears to transmit power. The end faces of the first and second driven gear shafts near the twin-screw assembly are located on the same plane. The end faces of the first and second driven gear shafts near the twin-screw assembly and the end faces of the first and second screws near the transmission device are aligned and coaxially fitted. The first connecting ring connects the end face of the first driven gear shaft near the twin-screw assembly and the end face of the first screw near the transmission device via a keyway. The second connecting ring connects the end face of the second driven gear shaft near the twin-screw assembly and the end face of the second screw near the transmission device via a keyway.
4. A solid-phase additive twin-screw mixing and extrusion apparatus according to claim 1 or 3, characterized in that, The second drive assembly includes a second driver, a gear, and a positioning block; the gear is fixedly mounted on the second driver; the positioning block is fixedly mounted on the end face of the gear near the stirring head, and the gear and the slewing bearing mesh with each other to transmit power.
5. A solid-phase additive twin-screw mixing and extrusion apparatus according to claim 4, characterized in that, The inner wall of the die head is designed to be inclined to prevent the plastic material from accumulating in the cavity and to guide the plastic material to be extruded towards the discharge hole.
6. A solid-phase additive twin-screw mixing and extrusion apparatus according to claim 1, characterized in that, The bottom of the stirring head has protrusions processed around the center of the discharge hole, which are distributed in a circular array, radially, uniformly, or symmetrically.
7. A solid-phase additive twin-screw mixing and extrusion apparatus according to claim 1, characterized in that, The barrel is a segmented barrel, including a feeding section barrel, a plasticizing section barrel, a mixing section barrel, an exhaust section barrel, and a metering section barrel; the top of the feeding section barrel is detachably installed at the bottom of the fixed connecting seat; the top of the plasticizing section barrel is detachably installed at the bottom of the feeding section barrel; the top of the mixing section barrel is detachably installed at the bottom of the plasticizing section barrel; the top of the exhaust section barrel is detachably installed at the bottom of the mixing section barrel; the top of the metering section barrel is detachably installed at the bottom of the exhaust section barrel; and the top of the die head is detachably installed at the bottom of the metering section barrel.
8. A solid-phase additive twin-screw mixing and extrusion apparatus according to claim 1, characterized in that, The feeding hole is machined on the side near the top of the feeding section barrel and extends to the inner wall of the barrel. Cooling liquid channels are machined inside the walls of the feeding section barrel and the metering section barrel. Each cooling liquid channel is connected to one inlet hole and one outlet hole. The inlet hole is located on the side near the top of the barrel in the feeding section barrel and the metering section barrel and connects to the cooling liquid channel. The outlet hole is located on the side near the bottom of the barrel in the feeding section barrel and the metering section barrel and connects to the cooling liquid channel. The vent hole is located on the side near the bottom of the barrel in the venting section barrel and extends to the inner wall of the barrel. A breathable membrane is fixedly installed on the side of the vent hole near the inner wall of the venting section barrel, or it is connected to an automatic vent valve or a vacuum pump. The electromagnetic induction heating coil is wound around the outer wall of the plasticizing section barrel and the mixing section barrel. The temperature sensor is fixedly embedded in the inner wall of the feeding section barrel, the metering section barrel, the plasticizing section barrel, and the mixing section barrel.
9. A solid-phase additive twin-screw mixing and extrusion apparatus according to claim 1, characterized in that, The first screw and the second screw are combined screws.
10. A method for implementing the solid-phase additive twin-screw mixing and extrusion apparatus as described in any one of claims 1-9, comprising the following steps: Step 1: Based on the material properties and process requirements used in additive manufacturing, select barrel and screw components for combination, assemble the twin-screw mixing and extrusion device, and fix it to the first drive device, and connect the power supply to each working component; Step 2: Obtain the data of the workpiece to be processed through modeling or scanning, and compile the corresponding CNC code; Step 3: Prepare the raw materials required for additive manufacturing, load them into the corresponding feeder, and feed one or more types of materials into one or more corresponding feed holes. Check and debug the equipment. Step 4: Fix the prepared work substrate onto the worktable; Step 5: Control the twin-screw mixing and extrusion device to move to the starting position of the matrix to be additively manufactured area; Step 6: The feeder starts to continuously feed material into the feeding hole; the first drive device drives the transmission device in the twin-screw mixing and extrusion device, and the power is transmitted to the twin screw by the transmission device. The twin screw, which rotates at a certain speed, conveys, crushes, compresses and shears the fed material; the electromagnetic induction heating coil and the cold liquid channel start to work; the second drive device drives the slewing bearing to rotate, and then drives the mixing head to start rotating at a certain speed. Step 7: Control the movement of the twin-screw agitator and extruder so that there is a suitable gap between the rotating agitator head shoulder and the substrate surface or the surface of the previous deposited layer, leaving a distance for the additive layer; a part of the agitator head protrusion penetrates into the substrate or the previous deposited layer to generate heat through agitation and friction, and begins to plasticize the substrate surface or the surface of the previous deposited layer. Step 8: As the twin-screw assembly rotates and extrudes, new plasticized material is extruded from the discharge port and flows along the space between the agitator shoulder and the substrate surface or the surface of the previous deposited layer; under the continuous rotation and stirring friction of the agitator and protrusion, the new plasticized material and the substrate surface material plasticized by stirring friction or the previous deposited surface material plasticized by stirring friction of the protrusion mix with each other, undergoing metallurgical bonding and dynamic recrystallization to form an additive deposited layer with a certain height; Step 9: As the twin-screw agitator and extruder move continuously in the additive zone, the first additive layer is obtained. If multiple additive layers need to be printed, after the first additive layer is completed, the twin-screw agitator and extruder is raised to a certain height and positioned to the next starting position. Steps 6, 7, and 8 are repeated to achieve continuous solid-phase additive manufacturing, avoid errors caused by re-clamping, and improve additive manufacturing efficiency.