Composite material dynamic force field forming device, forming method and application

Abstract

The invention provides a dynamic force field forming device and method for a composite material and application of the dynamic force field forming device and method, and belongs to the technical field of dynamic force field forming devices. The device comprises a rack, wherein a lifting mechanism is arranged on the rack; the heat insulation workbench is arranged on the lifting mechanism; the heating table is arranged on the heat insulation workbench; the lower mold pressing head is arranged on the heating table and is used for limiting the range of the blend; and the high-frequency ultrasonic force field generating device is arranged above the lower mold pressing head, and an upper mold pressing head on the high-frequency ultrasonic force field generating device is matched with the lower mold pressing head and used for applying a low-frequency circulating force field and intermittently loading a high-frequency ultrasonic force field to the blend. According to the invention, the high-frequency ultrasonic force field generating device applies a low-frequency circulating force field to the blend and intermittently loads the high-frequency ultrasonic force field, so that the arrangement and orientation of the functional filler in the polymer matrix are accurately controlled; and the filler-matrix interaction is enhanced. Therefore, macroscopic / microcosmic form regulation and control of the composite material are realized, and the performance of the composite material is greatly improved under the condition of low filler consumption.

Description

Technical Field

[0001] The present invention relates to the technical field of dynamic force field forming devices, and in particular to a composite material dynamic force field forming device and a forming method and application thereof. Background Art

[0002] Polymer-based composites have become strategic materials due to their wide application in key areas such as aerospace, wind power generation, rail transit and automobiles. At present, an industrialization system including key technology research and development and engineering application has been established. In particular, ultrasonic machining technology has been widely studied and applied due to its unique advantages. This technology can accurately process and treat materials at a microscopic scale through the transmission of high-frequency vibration energy, and has shown great potential in the interface bonding and interlaminar reinforcement of composite materials. Ultrasonic vibration can effectively improve the bonding performance between fibers and matrix, thereby improving the overall performance of composite materials. In addition, ultrasonic vibration can also be used to promote the penetration of resin between fiber bundles and enhance the interlaminar shear strength of composite materials. Ultrasonic machining can not only reduce material damage, but also improve processing efficiency and product quality. However, with the development of technology and the increase in application needs, ultrasonic machining technology also faces some challenges and room for improvement. Traditional ultrasonic machining methods still have limitations in material compaction and improvement of thermal / electrical conductivity.

[0003] To overcome these limitations, researchers are exploring new ultrasonic machining technologies and their combined applications with composite materials. For example, by adjusting the frequency and amplitude of ultrasonic vibrations, the compaction effect of the material can be optimized and its density and uniformity can be improved. In addition, combining ultrasonic vibrations with heat treatment or electric field treatment can further improve the thermal and electrical conductivity of composite materials. Researchers are also exploring the combination of ultrasonic machining with other advanced machining technologies, such as laser machining, electrochemical machining, etc., to achieve more complex composite structures and functions. This multi-technology fusion approach is expected to bring revolutionary breakthroughs in the preparation of composite materials.

[0004] The prior art has the following defects: Limitations of existing technologies: Traditional steady-state force field forming technology may have some limitations, such as difficulty in achieving fine control of material properties, or low efficiency in the preparation of composite materials.

[0005] Efficiency issues: Traditional technologies mainly rely on chemical modification and material screening to improve performance, lacking innovation from the perspective of processing methods. Traditional steady-state force field molding technology has limitations in production efficiency. Many traditional steady-state molding processes require a long time of curing or heat treatment, and need to be cleaned and reconfigured after each production cycle. It is difficult to adapt to product changes or customization needs, limiting the ability to respond quickly to the market.

[0006] Uneven dispersion of functional fillers: In the polymer matrix, the uniformity of the dispersion of functional fillers is critical to the overall performance of the material. Uneven dispersion may lead to inconsistency and anisotropy of material properties, which in turn affects the mechanical strength, durability and functionality of the material.

[0007] Complex processing technology: At present, the preparation process of polymer composites generally has problems such as complex operation, high cost, and low energy efficiency, which limit its wide application in industrial production. It is imperative to develop a processing technology that is both simple and efficient.

[0008] Growing demand for composite materials: With the development of science and technology, the demand for high-performance composite materials is increasing, especially in the fields of aerospace, automobile manufacturing, etc.

[0009] Innovation in processing technology: In order to improve the performance and preparation efficiency of materials, it is urgently necessary to innovate from the perspective of processing methods in addition to chemical modification and material screening, and to find new ways to improve the microstructure and macroscopic properties of materials. Summary of the invention

[0010] In view of this, in order to achieve macroscopic / microscopic morphology control of composite materials and ensure a significant improvement in the performance of composite materials at low filler dosage, in the first aspect, the present invention provides a composite material dynamic force field forming device, which applies a low-frequency cyclic force field and intermittently loads a high-frequency ultrasonic force field to the blend through a high-frequency ultrasonic force field generating device, accurately controls the arrangement and orientation of functional fillers in the polymer matrix; affects the fluidity, aggregate structure and curing characteristics of the polymer matrix; and strengthens the interaction between fillers and matrix. Thus, the macroscopic / microscopic morphology control of composite materials is achieved, ensuring a significant improvement in the performance of composite materials at low filler dosage.

[0011] To achieve the above object, the present invention provides the following technical solutions: A composite material dynamic force field forming device, comprising: A frame, on which a lifting mechanism is arranged; A heat-insulating workbench, which is arranged on the lifting mechanism; A heating table, which is arranged on the heat-insulating workbench; A lower die head, which is arranged on the heating platform and is used to confine the blend; A high-frequency ultrasonic force field generating device is arranged above the lower die pressing head, and the upper die pressing head thereon cooperates with the lower die pressing head to apply a low-frequency cyclic force field and intermittently load a high-frequency ultrasonic force field to the blend.

[0012] Preferably, the lifting mechanism is a scissors lifting mechanism.

[0013] Preferably, the scissor lift mechanism comprises: A first connecting rod and a second connecting rod are cross-rotatably connected, one end of the first connecting rod is rotatably connected to the frame, and the other end is slidably connected to the insulation workbench, and one end of the second connecting rod is slidably connected to the frame, and the other end is rotatably connected to the insulation workbench; An upper connecting rod, two ends of which are respectively hinged to the first connecting rods located on both sides of the frame; A plurality of lower connecting rods, wherein the lower connecting rods are used to connect two ends of the two first connecting rods and two second connecting rods, so that the first connecting rods rotate on the frame and slide on the heat-insulating workbench, and the second connecting rods slide on the frame and rotate on the heat-insulating workbench; The two ends of the power driving device are respectively connected between the upper connecting rod and the lower connecting rod.

[0014] Preferably, the first connecting rod and the heat-insulating workbench and / or the second connecting rod and the frame are slidably connected via bearing guide rails.

[0015] Preferably, the cross section of the upper die pressing head is circular or square.

[0016] Preferably, the heating stage controls the heating temperature and the heat preservation time through a heating controller.

[0017] Preferably, the high-frequency ultrasonic force field generating device is composed of an amplitude modulator, a transducer, a lower die pressing head and a generator. The generator is used to convert the power supply into high-frequency and high-voltage electric waves using electronic circuits, which are converted into mechanical waves through the transducer, and then transmitted and amplified to act on the surface of the blend through the lower die pressing head.

[0018] In a second aspect, the present invention provides a molding method of the above composite material dynamic force field molding device, comprising the following steps: Step (1): After the heating table is preheated, the blend is placed into the lower die head; Step (2): After setting the pressure parameters, the blend is pressurized, and the blended raw materials are compressed in a confined area through a low-frequency cyclic force field to construct a dense functional filler network; Step (3): adjusting the parameters of the high-frequency ultrasonic force field, introducing ultrasonic waves to perform intermittent loading under the constant temperature and pressure state in step (2), and then releasing the pressure after a period of time, so that the system is in a relaxed state; Step (4): Repeat the process of steps (2) and (3) as needed; Step (5): Complete final curing under constant temperature and pressure or directly cool and then open the mold.

[0019] Preferably, in step (2), the low-frequency cyclic force field has a frequency of <1 Hz, and in step (3), the parameters of the high-frequency ultrasonic force field are power 100-500 W, time 5-20 s, and frequency ≥20 kHz.

[0020] In a third aspect, the present invention provides the application of the above-mentioned composite material dynamic force field forming device and the forming method of the above-mentioned composite material dynamic force field forming device in thermosetting polymer composite materials and thermoplastic polymer composite materials.

[0021] Compared with the prior art, the present invention has the following beneficial effects: The above-mentioned dynamic force field forming device for composite materials provided by the present invention can meet the customization and controllability requirements for low-frequency cyclic force fields and high-frequency ultrasonic force fields in the dynamic force field forming process, and provides a new and efficient solution for the field of composite material preparation.

[0022] The composite material dynamic force field forming device provided by the present invention applies a low-frequency cyclic force field and an intermittently loaded high-frequency ultrasonic force field to the blend through a high-frequency ultrasonic force field generating device, and accurately controls the arrangement and orientation of the functional filler in the polymer matrix by controlling the low-frequency cyclic force field and the high-frequency ultrasonic force field, thereby affecting the fluidity, aggregate structure and curing characteristics of the polymer matrix and strengthening the filler-matrix interaction. Thus, the macroscopic / microscopic morphology control of the composite material is achieved, ensuring a substantial improvement in the performance of the composite material.

[0023] The present invention is different from the traditional steady-state force field forming method. The forming method provided by the present invention innovatively introduces two different dynamic force field loading methods, low-frequency cyclic force field and high-frequency ultrasonic force field, in the preparation process of polymer-based composite materials. The introduction of the low-frequency cyclic force field causes the material to undergo forced compression at the macro level, and the particles are redistributed in the matrix to form a more compact filler network, thereby improving the overall performance of the material (including mechanical properties and electrical / thermal conductivity, etc.); while the addition of the high-frequency ultrasonic force field provides high-frequency vibration for the material at the micro level. This vibration helps to promote the flow and filling of the resin, thereby reducing the internal stress of the material caused by temperature changes, promoting the wetting and penetration of the matrix material on the filler surface, thereby improving the adhesion of the interface, helping to eliminate the micropores and defects inside the material, making the composite material after molding more dense, and improving the tensile strength and compressive strength of the material. This vibration can effectively promote the interface bonding between the filler and the matrix and enhance the interface strength of the composite material. The precise regulation of polymer composite materials is achieved. Starting from the evolution of macroscopic and microscopic morphology, the present invention pays special attention to the influence of factors such as filler network, matrix aggregation structure, and curing characteristics on the performance of composite materials. Through the regulation of dynamic force field, the fluidity of polymers can be promoted, thereby optimizing the mechanical properties and thermal stability of the materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure of the dynamic force field forming device for composite materials; Figure 2 It is a structural schematic diagram of the scissor lift mechanism; Figure 3 It is a structural schematic diagram of the scissor lift mechanism moving to the highest point; Figure 4 It is a structural schematic diagram of the scissor lift mechanism moving to the lowest point; Figure 5 It is a structural schematic diagram of the scissor lift mechanism moving from the highest point to the lowest point; Figure 6 Schematic diagram of temperature / pressure-time loading curve of the thermoplastic polymer composite material system prepared in Example 1; Figure 7 A schematic diagram of a temperature / pressure-time loading curve of a thermosetting polymer composite material system prepared in Example 2; Figure 8 The electron microscope photographs of the samples prepared by the compression molding and blending method and Example 2 of the present invention, wherein (a) is an electron microscope photograph of the sample prepared by the compression molding and blending method, and (b) is an electron microscope photograph of the sample prepared by the molding method of Example 2 of the present invention; Fig. 9 The mechanical properties of the samples prepared by comparative example 1 (compression molding and blending method) and example 2 of the present invention are compared; Fig.10 This is a physical picture of a sample prepared using Example 3 of the present invention; Fig.11 (a) is an electron microscope photograph of a sample prepared by Example 4 of the present invention; (b) is an electron microscope photograph of a sample prepared by Comparative Example 1 (compression molding and blending method); In the figure, 1, frame; 2, amplitude modulator; 3, transducer; 4, upper die head; 5, lower die head; 6, generator; 7, heating table; 8, bearing guide; 9, power drive device; 10, upper connecting rod; 11, lower connecting rod; 12, first rod; 13, second rod; 14, heat-insulating workbench; 15, heating controller. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making creative work are within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", "top / bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0027] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "mounted / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] First, as Figure 1-5 As shown, the present invention provides a composite material dynamic force field forming device, comprising: A frame 1, on which a lifting mechanism is arranged, and the frame 1 serves as a supporting structure of the entire device; The heat-insulating workbench 14 is arranged on the lifting mechanism, and the height of the heat-insulating workbench 14 is adjusted by the lifting mechanism. The lifting mechanism is preferably a scissor lift mechanism; A heating table 7, which is arranged on the insulating workbench 14 and has a heating device thereon, the heating device may preferably be a heating wire and / or a thermocouple, and the heating temperature and the heat preservation time are controlled by a heating controller 15, the heating device is more preferably a heating wire and a thermocouple; The lower die pressing head 5 is arranged on the heating platform 7 to confine the blend, and cooperates with the upper die pressing head 4 applying pressure load in the high-frequency ultrasonic force field generating device described below to confine and compress the blend in the lower die pressing head 5. The cross section of the upper die pressing head 4 is preferably circular or square, that is, the lower die pressing head 5 is a circular ring or square ring structure; A high-frequency ultrasonic force field generating device is arranged above the lower die pressing head 5, and the upper die pressing head 4 thereon cooperates with the lower die pressing head 5 to apply a low-frequency cyclic force field and intermittently load a high-frequency ultrasonic force field to the blend. The high-frequency ultrasonic force field generating device is preferably fixed to the upper end of the workbench and the rear end of the heating table 7, and is connected to the external generator 6 through a cable.

[0029] The present invention provides an implementation of the above-mentioned scissor lift mechanism, which is specifically as follows: The scissor lift mechanism comprises: The first connecting rod and the second connecting rod connected in a cross-rotation manner, that is, the front side of the scissor lift mechanism ( Figure 3-4 The first connecting rod and the second connecting rod (on the side directly opposite to the center) are cross-hinged together, and the two can rotate; One end of the first connecting rod is rotatably connected to the frame 1, and the other end is slidably connected to the insulation workbench 14; one end of the second connecting rod is slidably connected to the frame 1, and the other end is rotatably connected to the insulation workbench 14; Figure 1-4 As shown, in the front and rear sides of the scissor lift mechanism, one end of the frame formed by the first connecting rod rotates on the frame 1, and the other end slides on the insulation workbench 14; one end of the frame formed by the second connecting rod slides on the frame 1, and the other end rotates on the insulation workbench 14; An upper connecting rod 10, two ends of which are respectively hinged to the first connecting rods located on both sides of the frame 1; A plurality of lower connecting rods 11, wherein the lower connecting rods 11 are used to connect the two ends of the first connecting rods and the two second connecting rods, so that the first connecting rods rotate on the frame 1 and slide on the insulation workbench 14, and the second connecting rods slide on the frame 1 and rotate on the insulation workbench 14; Figure 3 As shown, both ends of the frame formed by the first connecting rod and both ends of the frame formed by the second connecting rod are connected by the lower connecting rod 11 and rotate around the lower connecting rod 11; The two ends of the power driving device 9 are respectively connected between the upper connecting rod 10 and the lower connecting rod 11. The power driving device 9 applies driving force to drive the scissor lift mechanism.

[0030] In the present invention, the first connecting rod and the insulation workbench 14 and / or the second connecting rod and the frame 1 are slidably connected via a bearing guide rail 8, wherein the bearing guide rail 8 between the first connecting rod and the insulation workbench 14 is fixed on the insulation workbench 14, and the first connecting rod slides on the bearing guide rail 8; the bearing guide rail 8 between the second connecting rod and the frame 1 is fixed on the frame 1, and the second connecting rod slides on the bearing guide rail 8, which can be specifically: Bearings are installed at both ends of the lower connecting rod 11, and the bearings slide backward or forward on the bearing guide rail 8, thereby realizing the lifting and lowering of the heat-insulating workbench 14.

[0031] The power drive device 9 includes but is not limited to pneumatic drive, electric cylinder drive, hydraulic drive, etc., and can reach the designated position for pressurization and pressure relief. Those skilled in the art can freely choose according to actual needs.

[0032] In the present invention, the high-frequency ultrasonic force field generating device is composed of an amplitude modulator 2, a transducer 3, a lower die pressing head 5 and a generator 6. The generator 6 is used to convert the power supply into a high-frequency and high-voltage electric wave using an electronic circuit, which is converted into a mechanical wave through the transducer 3, and then transmitted and amplified to act on the surface of the blend through the lower die pressing head 5.

[0033] In a second aspect, the present invention provides a molding method of the above composite material dynamic force field molding device, wherein the composite material preferably includes a thermosetting polymer composite material and a thermoplastic polymer composite material; The steps include: Step (1): After the heating table 7 is preheated, the blend is placed in the lower mold head 5; wherein, for thermosetting polymer composite materials, the blend is a mixture of functional fillers, polymer matrix and curing agent; for thermoplastic polymer composite materials, the blend is a mixture of functional fillers and polymer matrix; Step (2): After setting the pressure parameters, pressurize the blend, and perform confined compression on the blended raw materials through a low-frequency cyclic force field to construct a dense functional filler network; wherein the pressure parameter range is preferably 3-5 MPa; and the frequency of the low-frequency cyclic force field is less than 1 Hz; Step (3): adjusting the parameters of the high-frequency ultrasonic force field, introducing ultrasonic waves to perform intermittent loading under the constant temperature and pressure state in step (2), and then releasing the pressure after a period of time, so that the system is in a relaxed state; wherein the parameters of the high-frequency ultrasonic force field are preferably 100-500W, time 5-20s, and frequency ≥20kHz, and more preferably 300W, time 10s, and frequency ≥20kHz; Step (4): Repeat the process of steps (2) and (3) as needed; Step (5): Complete final curing under constant temperature and pressure or directly cool and then open the mold.

[0034] When a thermosetting polymer composite material is selected, step (5) completes final curing under a constant temperature and pressure state; when a thermoplastic polymer composite material is selected, step (5) is directly cooled and then the mold is opened to obtain a composite material product.

[0035] In the present invention, in step (2), the low-frequency cyclic force field has a frequency of <1 Hz, and in step (3), the parameters of the high-frequency ultrasonic force field are preferably 100-500 W, time 5-20 s, and frequency ≥20 kHz, more preferably 300 W, time 10 s, and frequency ≥20 kHz.

[0036] In a third aspect, the present invention provides the application of the above-mentioned composite material dynamic force field forming device and the forming method of the above-mentioned composite material dynamic force field forming device in thermosetting polymer composite materials and thermoplastic polymer composite materials.

[0037] The technical solution of the present invention is described in detail below in conjunction with specific embodiments, as follows:

[0038] Example 1

[0039] This embodiment provides a molding method of a thermoplastic polymer composite material, comprising the following steps: Step (1), short carbon fiber (SCF) and carbon nanotube (CNT) are selected as thermal conductive fillers, polyamide (PA) is selected as the polymer matrix, SCF and CNT are dispersed in PA according to a certain ratio, the heating table 77 is preheated to 80° C., and the blend is placed in the lower mold head 5 at the same time; Step (2), after the input pressure is 5 MPa, the power drive device 9 is started, and the total stroke is 450 mm. When the insulation workbench 14 reaches the highest point, the platform height is 800 mm, and the power drive device 9 is at 45° to the horizontal plane; at this time, the confined compression step is performed, and the pressure reaches the maximum value after 2 minutes; Step (3), setting the frequency and power of the high-frequency ultrasonic force field generating device, intermittently loading the high-frequency ultrasonic force field under constant temperature and pressure, specifically, applying ultrasonic vibration with a frequency of 28 kHz and a power of 300 W to accelerate the molding, during which the ultrasonic wave acts on the blend for 10 s as a cycle, and the pressure is released after 2 minutes of zero pressure. After 2 minutes, the system is relaxed.

[0040] Step (4), repeat the above steps (2) and (3) twice; Step (5), turn off the heating system, and the blend is naturally cooled to room temperature in the lower mold head 5, and the mold is finally opened. At this time, when the insulation workbench 14 drops to the lowest point, the platform height is 350 mm, the double-acting pneumatic cylinder is 15° with the horizontal plane, and the lengths of the first rod 12 and the second rod 13 are both 1000 mm. Figure 7 As shown, the temperature / pressure-time loading curve of the thermoplastic polymer composite system prepared in Example 1 is shown.

[0041] Example 2

[0042] This embodiment provides a molding method of a thermosetting polymer composite material, comprising the following steps: Step (1), aluminum nitride (AlN) and boron nitride (BNNS) are used as thermal conductive fillers, epoxy resin (EP) is used as the polymer matrix, AlN and BNNS are dispersed in EP in a certain proportion, a curing agent is added, and the heating table 77 is preheated to 120° C. The blend is placed in the lower mold head 5 at the same time.

[0043] Step (2), after the input pressure reaches 3 MPa, the power drive device 9 is started, and the total stroke is 450 mm. When the insulation workbench 14 reaches the highest point, the platform height is 800 mm, and the power drive device 9 is at 45° to the horizontal plane. At this time, the confined compression step is performed, and the pressure reaches the maximum value after 2 minutes.

[0044] Step (3), setting the amplitude and power of the high-frequency ultrasonic force field generating device, intermittently loading the high-frequency ultrasonic force field under the pressure-maintaining state, specifically, applying ultrasonic vibration with a frequency of 25 kHz and a power of 300 W to accelerate the molding, during which the ultrasonic wave acts on the blend for 10 s as one cycle, and the pressure is released after 2 minutes of continuous operation. After 2 minutes of zero pressure, the system is relaxed.

[0045] Step (4), repeat the above steps (2) and (3) twice, add curing agent, and complete the curing process under constant temperature and pressure.

[0046] Step (5), turn off the heating system, and the blend completes final curing under constant temperature and pressure. At this time, when the insulation workbench 14 drops to the lowest point, the platform height is 350 mm, the double-acting pneumatic cylinder is 15° with the horizontal plane, and the lengths of the first rod 12 and the second rod 13 are both 1000 mm.

[0047] Example 3 This embodiment provides a molding method for a thermoplastic polymer composite material, which first uses a filtration technique to construct a filler network, and then uses a dynamic force field molding technique to introduce a polymer matrix to complete the infiltration molding method, including the following steps: Step (1), carbon nanotube (CNT) and graphene powder are mixed with a suitable dispersant to form a uniform suspension. Then, the suspension is passed through filter paper using a suction filtration device, and the solvent is extracted by vacuum suction, thereby forming a mixed film of CNT and graphene on the filter paper. Polyamide (PA) is selected as the matrix material, and the heating table 7 is preheated to 80°C and heated to a molten state. Subsequently, the CNT and graphene film coated with polyamide is placed in the lower die head 5.

[0048] Step (2), applying a pressure of 5 MPa for confined compression, the pressure reaches the maximum value after 2 min. Step (3), setting the amplitude and power of the high-frequency ultrasonic force field generating device, intermittently loading the high-frequency ultrasonic force field under constant temperature and pressure, specifically, applying ultrasonic vibration with a frequency of 28 kHz and a power of 300 W to accelerate the molding, during which the ultrasonic wave acts on the blend for 10 s as one cycle, and the pressure is released after 2 minutes of zero pressure. After 2 minutes of zero pressure, the system is relaxed.

[0049] Step (4): Repeat the above steps (2) and (3) twice.

[0050] Step (5), turn off the heating system, and allow the blend to cool naturally to room temperature in the lower die head 5, and finally complete the mold opening. Fig.10 A physical picture of the sample prepared in Example 3 is shown.

[0051] Example 4 This embodiment provides a molding method for a thermoplastic polymer composite material, wherein a polymer matrix doped with a small amount of filler is impregnated into a fiber cloth to prepare a molding method for a functional prepreg, comprising the following steps: Step (1), select short carbon fiber (SCF) and carbon nanotube (CNT) as thermal conductive fillers, select epoxy resin of appropriate grade as matrix material, disperse SCF and CNT into epoxy resin according to a predetermined ratio and add curing agent, use ultrasonic disperser to ensure uniform dispersion, and preheat the heating table 7 to 120°C. Select appropriate fiber cloth, such as quartz fiber cloth, pretreat, and evenly coat the epoxy resin doped with SCF and CNT on the surface of the fiber cloth, then arrange and stack according to design requirements to form a preform. Place the preform in the lower die head 55.

[0052] Step (2), after applying a pressure of 3 MPa, the power drive device 9 is started, and the total stroke is 450 mm. When the insulation workbench 14 reaches the highest point, the platform height is 800 mm, and the power drive device 9 is at 45° to the horizontal plane; at this time, the confined compression step is performed, and the pressure reaches the maximum value after 2 minutes.

[0053] Step (3), setting the amplitude and power of the high-frequency ultrasonic force field generating device, intermittently loading the high-frequency ultrasonic force field under the pressure-maintaining state, specifically, applying ultrasonic vibration with a frequency of 25 kHz and a power of 300 W to accelerate the molding, during which the ultrasonic wave acts on the blend for 10 s as one cycle, and the pressure is released after 2 minutes of continuous operation. After 2 minutes of zero pressure, the system is relaxed.

[0054] Step (4): Repeat the above steps (2) and (3) twice to promote the flow and curing of the epoxy resin.

[0055] Step (5), turn off the heating system, and the blend completes the curing process under constant temperature and pressure. At this time, when the insulation workbench 14 drops to the lowest point, the platform height is 350 mm, the double-acting pneumatic cylinder is 15° with the horizontal plane, and the lengths of the first rod 12 and the second rod 13 are both 1000 mm. Fig.11 (a) shows an electron micrograph of the sample of Example 4.

[0056] Existing technologies such as compression blending, hot pressing, stamping, vacuum-assisted resin transfer molding, etc., mainly rely on traditional steady-state force field molding technology in the field of composite material molding. This method has limitations in material compaction and improving thermal / electrical conductivity. These traditional methods are not only difficult to achieve fine control of material properties, but also have problems such as low efficiency in the preparation of composite materials. They usually rely on chemical modification and material screening to improve performance, and lack innovation from the perspective of processing methods. In addition, traditional steady-state force field molding technology has limitations in production efficiency. The molding process often requires long-term curing or heat treatment, and cleaning after each experimental cycle. These preparation processes are generally complex to operate, costly, and energy-inefficient. It is difficult to adapt to product changes or customization needs, which limits the ability to respond quickly to the market.

[0057] Comparative Example 1 The conventional compression molding blending method is adopted, and the parameters such as the selected raw materials and their proportions are the same as those in Example 2. The only difference is that Example 2 adopts a low-frequency circulating force field and a high-frequency ultrasonic force field.

[0058] The mechanical properties of Comparative Example 1 and Example 2 are compared. Fig. 9 The electron microscope photos of the real objects of Comparative Example 1 and Example 2 are shown in Figure 8 The temperature / pressure-time loading curve of the thermosetting polymer composite material prepared in Example 2 is shown in Figure 7 shown.

[0059] Existing technologies, such as hot pressing, mainly rely on traditional steady-state force field forming technology in the field of composite material forming. This method has limitations in material compaction and improving thermal / electrical conductivity. It is not only difficult to achieve fine control of material properties, but also has problems such as low efficiency in the preparation of composite materials. It usually relies on chemical modification and material screening to improve performance, but lacks innovation from the perspective of processing methods. In addition, traditional steady-state force field forming technology has limitations in production efficiency. The forming process often requires long-term curing or heat treatment, and cleaning after each experimental cycle. These preparation processes are generally complex to operate, costly, and energy-inefficient. It is difficult to adapt to product changes or customization needs, which limits the ability to respond quickly to the market.

[0060] In the preliminary verification experiments of the present invention, the photos taken by electron microscope (such as Figure 6The images clearly show the remarkable results achieved by the method described in this patent in preparing samples. Compared with the prior art, the samples prepared by the present invention have achieved a significant improvement in the wetting effect. The samples prepared by the method of the present invention show a more uniform filler dispersion and a better matrix wetting effect. This is because the introduction of the dynamic force field optimizes the resin flow and filler distribution, while effectively reducing the defects in the product. In addition, the composite product prepared by the present invention also has a significant improvement of 53% in tensile properties. This significant performance improvement is due to the improvement of the internal structure of the composite material, including fewer defects and more uniform stress distribution. The synergistic effect of the low-frequency cyclic force field and the high-frequency ultrasonic force field promotes the optimization of the internal microstructure of the material, thereby enhancing the overall consistency and mechanical properties of the material.

[0061] Compared with the prior art, the present invention realizes precise control of polymer composite materials by introducing two different dynamic force field loading methods, namely low-frequency cyclic force field and high-frequency ultrasonic force field. By precisely controlling the low-frequency cyclic force field and the high-frequency ultrasonic force field, the arrangement and orientation of the functional filler in the polymer matrix can be controlled, affecting the fluidity, aggregate structure and curing characteristics of the polymer matrix, and strengthening the interaction between the filler and the matrix, so that the macroscopic and microscopic morphology of the composite material is effectively controlled, ensuring a significant improvement in the performance of the composite material at a low filler dosage.

[0062] The above are only preferred specific implementations of the present invention; however, the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and improved concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A composite material dynamic force field forming device, characterized in that: include: A frame, on which a lifting mechanism is arranged; A heat-insulating workbench, which is arranged on the lifting mechanism; A heating table, which is arranged on the heat-insulating workbench; A lower die head, which is arranged on the heating platform and is used to confine the blend; A high-frequency ultrasonic force field generating device is arranged above the lower die pressing head, and the upper die pressing head thereon cooperates with the lower die pressing head to apply a low-frequency cyclic force field and intermittently load a high-frequency ultrasonic force field to the blend.

2. A composite material dynamic force field forming device according to claim 1, characterized in that: The lifting mechanism is a scissors lifting mechanism.

3. A composite material dynamic force field forming device according to claim 2, characterized in that: The scissor lift mechanism comprises: A first connecting rod and a second connecting rod are cross-rotatably connected, one end of the first connecting rod is rotatably connected to the frame, and the other end is slidably connected to the insulation workbench, and one end of the second connecting rod is slidably connected to the frame, and the other end is rotatably connected to the insulation workbench; An upper connecting rod, two ends of which are respectively hinged to the first connecting rods located on both sides of the frame; A plurality of lower connecting rods, wherein the lower connecting rods are used to connect two ends of the two first connecting rods and two second connecting rods, so that the first connecting rods rotate on the frame and slide on the heat-insulating workbench, and the second connecting rods slide on the frame and rotate on the heat-insulating workbench; The two ends of the power driving device are respectively connected between the upper connecting rod and the lower connecting rod.

4. A composite material dynamic force field forming device according to claim 3, characterized in that: The first connecting rod and the heat-insulating workbench and / or the second connecting rod and the frame are slidably connected via bearing guide rails.

5. A composite material dynamic force field forming device according to claim 1, characterized in that: The cross section of the upper die pressing head is circular or square.

6. A composite material dynamic force field forming device according to claim 1, characterized in that: The heating table controls the heating temperature and the heat preservation time through a heating controller.

7. A composite material dynamic force field forming device according to any one of claims 1 to 6, characterized in that: The high-frequency ultrasonic force field generating device is composed of an amplitude modulator, a transducer, a lower die pressing head and a generator. The generator is used to convert the power supply into high-frequency and high-voltage electric waves using electronic circuits, which are converted into mechanical waves through the transducer, and then act on the surface of the blend through the lower die pressing head after transmission and amplification.

8. A forming method of a composite material dynamic force field forming device according to any one of claims 1 to 7, characterized in that: The steps include: Step (1): After the heating table is preheated, the blend is placed into the lower die head; Step (2): After setting the pressure parameters, the blend is pressurized, and the blended raw materials are compressed in a confined area through a low-frequency cyclic force field to construct a dense functional filler network; Step (3): adjusting the parameters of the high-frequency ultrasonic force field, introducing ultrasonic waves to perform intermittent loading under the constant temperature and pressure state in step (2), and then releasing the pressure after a period of time, so that the system is in a relaxed state; Step (4): Repeat the process of steps (2) and (3) as needed; Step (5): Complete final curing under constant temperature and pressure or directly cool and then open the mold.

9. The forming method of a composite material dynamic force field forming device according to claim 8, characterized in that: In step (2), the low-frequency cyclic force field has a frequency of <1 Hz, and in step (3), the parameters of the high-frequency ultrasonic force field are power 100-500W, time 5-20s, and frequency ≥20kHz.

10. Application of a composite material dynamic force field forming device according to any one of claims 1 to 7 and a forming method of a composite material dynamic force field forming device according to any one of claims 8 to 9 in thermosetting polymer composite materials and thermoplastic polymer composite materials.

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