A fiber orientation reinforced resin matrix composite material molding apparatus and method

Abstract

This invention discloses a molding equipment and method for fiber-oriented reinforced resin matrix composites, belonging to the field of composite material molding and manufacturing technology. The equipment includes, in sequence, a long fiber positioning device, a magnetic cap forming device, an air-drying and curing device, a matrix mixing device, a directional magnetic field device, a magnetic cap desorption device, a hot-pressing device, and a support platform. By individually positioning and limiting the long fibers, temporary magnetic response caps are formed at both ends. After air-drying and curing, these caps are mixed with the resin matrix. Under the action of the directional magnetic field, the long fibers achieve orderly arrangement. Subsequently, the magnetic caps are heated to soften and magnetically desorbed, and then dried and hot-pressed to obtain the directional reinforced resin matrix composite product. This invention, through the above-mentioned equipment, solves the technical problems in the prior art of achieving precise single-fiber positioning and orderly directional control of discrete long fibers in the resin matrix, the difficulty in subsequent removal of the auxiliary magnetic response medium, and the dispersed and uncontinuous implementation of the orientation and molding processes.

Description

Technical Field

[0001] This invention relates to the field of composite material molding and manufacturing technology, specifically to a fiber-oriented reinforced resin-based composite material molding equipment and method. Background Technology

[0002] Fiber-reinforced resin matrix composites have been widely used in aerospace, civil engineering reinforcement, and other fields due to their advantages such as high specific strength, high specific stiffness, excellent fatigue resistance, and strong designability. For these materials, the orientation, uniformity of distribution, and molding integrity of the reinforcing fibers in the resin matrix directly affect the final mechanical properties and service stability of the composite material. Therefore, how to achieve high-precision orientation and efficient molding of fibers, especially long fibers, in the resin system has always been an important research direction in this field.

[0003] While existing technologies have explored this issue from different angles, their technical paths differ from the problems this invention aims to solve. For example, CN117549574A primarily addresses directional control during prepreg layup and subsequent machining, falling under the category of layup auxiliary tooling solutions; CN116494530B mainly focuses on the three-dimensional orientation of magnetized short fibers in a liquid matrix; CN115609947A achieves orientation by directly adding steel fibers to epoxy resin and utilizing coils and vibration; CN112277338B emphasizes the electrostatic splitting, powdering, pre-compression, and arbitrary angle arrangement of continuous fiber bundles. These solutions are applicable to scenarios involving prepregs, short fibers, steel fiber colloids, or continuous fiber bundles, but they do not provide specific technical solutions for single-fiber positioning, end magnetization, non-contact orientation, subsequent desorption and removal, and continuous integrated molding of discrete long fibers in resin-based systems.

[0004] Especially in the preparation of discrete long fiber reinforced resin matrix composites, the existing technology still has the following prominent problems: First, long fibers are prone to bending, deflection, crossing and agglomeration during transportation, laying and mixing, making it difficult to achieve stable and orderly arrangement at the single fiber level; Second, existing magnetic field-assisted orientation mostly relies on whole fiber magnetization or matrix doping, and the magnetic components are usually retained inside the composite material, which can easily affect the purity of the material system and the fiber / matrix interface properties; Third, existing processes often implement the arrangement, orientation and molding separately, with poor process connection, making it difficult to balance orientation accuracy, fiber integrity and preparation efficiency.

[0005] In summary, existing technologies generally suffer from insufficient continuous and orderly control of long fibers, easy bending, deflection, or aggregation during orientation, difficulty in removing auxiliary magnetic response methods in subsequent processes, and the dispersed orientation and molding processes, making it difficult to balance efficiency and consistency. Therefore, there is an urgent need for a fiber-oriented reinforced resin matrix composite molding equipment and method that can achieve precise positioning and orderly orientation control of long fibers, allow for the desorption and removal of auxiliary media, and is suitable for continuous integrated molding. Summary of the Invention

[0006] The purpose of this invention is to provide a fiber-oriented reinforced resin matrix composite molding equipment and method to solve the technical problems in the prior art, such as the difficulty in achieving precise positioning and orderly orientation control of discrete long fibers in the resin matrix, the difficulty in subsequent removal of auxiliary magnetic response media, and the dispersed and difficult continuous implementation of orientation and molding processes. This invention achieves high-precision orientation arrangement of long fibers in the resin matrix system, desorption and removal of auxiliary magnetic response structures, and continuous and integrated molding preparation of composite materials.

[0007] This invention discloses a fiber-oriented reinforced resin matrix composite molding equipment, including a support platform, and a long fiber positioning device, a magnetic cap forming device, an air drying and curing device, a matrix mixing device, a directional magnetic field device, a magnetic cap desorption device, and a hot pressing device arranged sequentially on the support platform along the material processing and conveying direction. The long fiber positioning device is used for screening, untangling, guiding, positioning individual fibers, and recovering excess long fibers from long fiber raw materials. The magnetic cap forming device is used to attach temporary magnetic response media to the axial end regions of the positioned long fiber in sequence, so as to form magnetic caps for subsequent magnetic field orientation in the axial end regions of the long fiber. The air-drying and curing device is used to air-dry and cure the magnetic caps; The matrix mixing device is used to mix the long fibers that have been cured with double-ended magnetic caps with the resin matrix system, and to introduce the mixed material into the molding die. The directional magnetic field device is used to apply a directional magnetic field to the material in the molding die, so that the long fibers are adjusted from a disordered distribution state to an ordered state arranged along the target direction; The magnetic cap removal device is used to heat and soften the magnetic caps at both ends of long fibers after the fibers have been oriented, and then remove them by magnetic attraction, so that the magnetic caps can be separated from the long fibers and removed. The material after the magnetic caps have been removed is then dried. A hot press is used to hot press and cure a long fiber / resin matrix mixture that has been oriented and has had its magnetic cap removed, in order to obtain fiber-oriented reinforced resin matrix composite products.

[0008] Preferably, the long fiber positioning device includes a fixed platform that is slidably connected to the support platform via a guide rail. A push rod seat is installed on the fixed platform, and a telescopic push rod is provided inside the push rod seat. The top ends of multiple sets of push rods are hinged together to support a fiber positioning plate. The multiple sets of push rods are configured to extend or retract individually or in conjunction to drive the fiber positioning plate to achieve radial deflection and deflection along the long fiber axis. The upper surface of the fiber positioning plate is provided with multiple positioning grooves arranged in a predetermined direction to accommodate a single long fiber and limit the mutual interference between adjacent long fibers. The structural length of the fiber positioning plate along the axial direction of the long fiber is less than the length of the long fiber body, so that after the long fiber falls into the corresponding positioning groove, both ends of its axial direction extend beyond the corresponding end face of the fiber positioning plate. The long fiber positioning device also includes a feed trough, a drum screen, a guide plate and a recycling box arranged sequentially along the material flow direction. The end of the guide plate extends above the fiber positioning plate and is used to guide the long fibers after being screened and untangled by the drum screen to the fiber positioning plate. The radial deflection of the fiber positioning plate is used to make the long fibers fill the positioning grooves first and allow the excess long fibers that do not enter the positioning grooves to enter the recycling box. The deflection of the fiber positioning plate along the axial direction of the long fibers is used to make the two ends of the long fibers tilt toward the magnetic cap medium chamber of the subsequent magnetic cap forming device. The fixed platform is slidably connected to the support platform via guide rails and is used to transfer fiber positioning plates between adjacent workstations.

[0009] Preferably, the length of a single long fiber is 50-300 mm; the rotation speed of the drum screen is 10-40 r / min; the angle between the guide plate and the horizontal plane is 20-45°; the width of the positioning groove is 1.1-2.0 times the diameter of the long fiber; and the center distance between adjacent positioning grooves is 1.5-5.0 times the diameter of the long fiber.

[0010] Preferably, the magnetic cap forming device includes two sets of magnetic cap medium chambers arranged on the left and right sides respectively, and a forming groove communicating with the magnetic cap medium chambers; The magnetic cap medium chamber is used to store and supply the temporary magnetic response medium for forming the magnetic cap, and the forming groove is used to receive the temporary magnetic response medium and to allow the ends of long fibers to be dipped to form the magnetic cap. The working temperature of both the magnetic cap medium chamber and the forming tank is maintained at 75-90℃, so that the temporary magnetic response medium remains in a liquid state in the forming tank; The temporary magnetic response medium is composed of stearic acid and carbonyl iron powder, and the mass ratio of stearic acid to carbonyl iron powder is 1:2-1:6.

[0011] Preferably, the air-drying curing device includes an air-drying mechanism and an air-drying mechanism base. The air-drying mechanism is used to output a low-temperature airflow to air-dry and cure the magnetic caps at both ends of the long fiber. The temperature of the low-temperature airflow of the air-drying curing device is 15-35℃, the wind speed is 1-5 m / s, and the air-drying time is 10-60s.

[0012] Preferably, the mixing chamber is used to contain the long fiber and resin matrix system that has undergone double-ended magnetic cap curing; The agitator is located inside the mixing chamber and is used to agitate and mix the materials inside the mixing chamber, so that the long fibers and the resin matrix system are fully mixed to form a uniform long fiber / resin matrix system mixture. The molding die is used to receive the long fiber / resin matrix system mixture and serves as a supporting component for subsequent directional magnetic field treatment, magnetic cap desorption, and hot pressing. The forming mold slides with the guide rail set on the support platform to carry the material to flow between each station; The resin matrix system is a thermosetting resin matrix system suitable for hot pressing and curing, and is in a slurry, paste or flowable premixed state during the mixing and orientation stages, with a low viscosity of 5-10 Pa·s.

[0013] Preferably, the directional magnetic field device includes a Helmholtz coil mechanism and a coil support plate, the coil support plate being used to support and mount the Helmholtz coil mechanism, the Helmholtz coil mechanism being used to generate a directional magnetic field within its working area; The magnetic field strength of the directional magnetic field is 20-80 mT, and the magnetic field is applied for 10-120 s.

[0014] Preferably, the magnetic cap removal device includes a lifting mechanism, a pair of strong magnetic plates and a heating plate respectively disposed on the outer sides of both ends of the molding die. The strong magnetic plates move vertically closer to or further away from the molding die under the drive of the lifting mechanism, so that after the magnetic cap softens, it is adsorbed and removed by a non-uniform magnetic field and transferred to the surface of the strong magnetic plates for collection. When the strong magnetic plate is close to the end area of ​​the long fiber, the minimum distance between it and the corresponding end of the long fiber is 1-10 mm, and the time for a single magnetic cap removal action is 1-10 s. The hot pressing device includes a hot pressing power mechanism, a hot pressing mechanism support, and a cover plate. The support of the hot pressing mechanism is mounted on a support platform. The hot pressing power mechanism and the cover plate are respectively located on the upper and lower sides of the hot pressing mechanism support and are linked, so that the hot pressing power mechanism drives the cover plate to apply pressure to the material inside the molding die. The hot pressing temperature is 120-200℃, the hot pressing pressure is 2-20MPa, and the holding time is 1-30 min. The support platform includes a support table, guide rails, and guide rail supports. The guide rails are used to guide and limit the transfer of the fiber positioning plate and / or molding die between adjacent workstations.

[0015] The present invention also provides a method for molding fiber-oriented reinforced resin-based composite materials using the above-described equipment, comprising the following steps: S1. Non-magnetic long fiber raw materials are introduced into the long fiber positioning device, and the fiber positioning plate is driven to deflect radially by 5-15°. After screening, unwinding and guiding, the long fibers fall into the positioning grooves of the fiber positioning plate one by one. At the same time, the excess long fibers that do not enter the positioning grooves are recycled into the recycling box. After filling, the fiber positioning plate is in a horizontal state. S2. Drive the fiber positioning plate to deflect 20-40° to one side along the long fiber axis, so that one end of the long fiber contacts the temporary magnetic response medium in the liquid or semi-fluid dynamic state in the forming groove on the corresponding side to form an initial magnetic cap. Then deflect 20-40° to the other side after leveling, so that the other end of the long fiber contacts the temporary magnetic response medium in the forming groove on the other side to form another magnetic cap, thereby forming magnetic caps at both ends of the long fiber. S3. The long fibers forming the magnetic cap are fed into the air drying and curing device to air dry and cure the magnetic cap, so that it reaches a solid state that can support subsequent glue application and mixing without deformation or falling off. S4. Mix the long fibers that have been cured with the magnetic cap with the resin matrix system, and then pour the mixed material into the molding die. S5. Place the molding die in the working area of ​​the directional magnetic field device and apply a directional magnetic field to the long fiber / resin matrix system mixture with magnetic cap in the molding die. When the directional magnetic field is applied, the resin matrix system is in a low viscosity state of 5-10 Pa·s, causing the long fibers to rotate and orient under the action of the magnetic field, changing from a disordered distribution state to an ordered state arranged along the target direction. S6. After the long fibers are oriented, the material in the molding die is heated to the temperature that softens the magnetic caps using a heating plate. Then, the magnetic caps at both ends of the long fibers are symmetrically removed using a strong magnetic plate. The magnetic caps are transferred to the surface of the strong magnetic plate and collected. Then, the material is heated and dried to gradually transform the resin matrix system from a slurry state, paste state, or flowable premixed state into a powder state suitable for hot pressing. S7. After the material has been decapped and dried, it is hot-pressed and cured to obtain fiber-oriented reinforced resin-based composite material products.

[0016] Therefore, the present invention employs the above-described fiber-oriented reinforced resin matrix composite molding equipment and method, which has the following beneficial effects: 1. The device of this invention can achieve subsequent desorption and removal of the auxiliary magnetic response medium, reducing impurity residue. It imparts magnetic response capability to the fibers by temporarily attaching magnetic caps to both ends of the long fibers, and after magnetic field orientation is completed, the magnetic caps are desorbed and removed by a combination of heating softening and magnetic traction. This avoids the problem of magnetic media residue remaining inside the composite material in existing whole-fiber magnetization or matrix magnetization schemes, which is beneficial for maintaining the purity of the composite material system and the original properties of the fiber / matrix interface.

[0017] 2. Long fiber orientation can be adjusted non-contactly during the magnetic field orientation stage, reducing the risk of fiber damage. This invention temporarily magnetizes the fiber ends and uses a magnetic orientation field to pull and adjust the orientation of the long fibers. During the magnetic field orientation stage, there is no need to apply direct force to the fiber body using mechanical combing, forced clamping, or hard contact straightening methods. This reduces the risk of bending, wear, and surface damage to the long fibers during the orientation process, and is more conducive to maintaining the integrity of the long fibers.

[0018] 3. Improves the consistency and orientation accuracy of long fiber orientation control. This invention uses a long fiber positioning device to limit the distribution of long fibers, and combines it with a magnetic cap forming device, an air-drying curing device, and an orientation magnetic field device to gradually transform the long fibers from an initial disordered state to a unidirectional arrangement in the target direction. This improves the orientation consistency of long fibers in the matrix, reduces fiber deflection, crossing, and aggregation, and provides a more stable arrangement basis for subsequent molding.

[0019] 4. Enables a continuous, integrated molding process for long fiber oriented reinforced resin matrix composites. This invention integrates long fiber positioning, temporary end magnetization, air drying and curing, matrix mixing, magnetic field orientation, magnetic cap desorption, and hot pressing into a continuous molding process. This reduces repetitive transfers and process switching in traditional step-by-step processes, which helps improve preparation efficiency and enhances the stability and batch consistency of the composite material molding process. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0021] Figure 2 This is a schematic diagram of the long fiber positioning device in an embodiment of the present invention.

[0022] Figure 3 This is a schematic diagram of the magnetic cap forming device in an embodiment of the present invention.

[0023] Figure 4 This is a schematic diagram of the air-drying and curing device in an embodiment of the present invention.

[0024] Figure 5 This is a schematic diagram of the matrix mixing device in an embodiment of the present invention.

[0025] Figure 6 This is a schematic diagram of the directional magnetic field device in an embodiment of the present invention.

[0026] Figure 7 This is a schematic diagram of the magnetic cap desorption device in an embodiment of the present invention.

[0027] Figure 8 This is a schematic diagram of the hot pressing device in an embodiment of the present invention.

[0028] Figure 9 This is a schematic diagram of the support platform in an embodiment of the present invention.

[0029] Figure 10 This is a schematic diagram of the long fiber limiting and positioning state in an embodiment of the present invention.

[0030] Figure 11 This is a schematic diagram of the formation process of the long fiber double-ended magnetic cap in an embodiment of the present invention.

[0031] Figure 12 This is a schematic diagram illustrating the process by which long fibers change from disordered orientation to unidirectional orientation in an embodiment of the present invention and retain their orientation after the cap is removed.

[0032] Figure 13 This is a schematic diagram of the finished product structure of the long fiber reinforced resin matrix composite material in an embodiment of the present invention.

[0033] Figure 14 This is a flowchart of the molding method for fiber-oriented reinforced resin matrix composites in an embodiment of the present invention.

[0034] Figure label: 1. Long fiber positioning device; 2. Magnetic cap forming device; 3. Air drying and curing device; 4. Matrix mixing device; 5. Directional magnetic field device; 6. Magnetic cap desorption device; 7. Hot pressing device; 8. Support platform; 101. Fiber positioning plate; 102. Fixed platform; 103. Push rod; 104. Push rod seat; 105. Guide plate; 106. Rotary drum screen; 107. Feed chute; 108. Recycling bin; 201. Magnetic cap dielectric chamber; 202. Forming groove; 301. Drying mechanism; 302. Base of the drying mechanism; 401. Mixing chamber; 402. Agitator; 403. Molding mold; 501. Helmholtz coil mechanism; 502. Coil support plate; 601. Lifting mechanism; 602. Strong magnetic plate; 603. Heating plate; 701. Hot pressing power mechanism; 702. Hot pressing mechanism support; 703. Cover plate; 801. Support table; 802. Guide rail; 803. Guide rail bracket. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following description will be provided in conjunction with the accompanying drawings of the embodiments of the present invention. Figures 1 to 14The technical solutions of the present invention have been clearly and completely described. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] In the description of this invention, it should be understood that the terms "center", "around", "lateral", "longitudinal", "length", "thickness", "angle", "up", "down", "left", "right", etc., which indicate the orientation or location, are limited to simplifying the description of this invention and are not specific locations or orientations. The above terms are not intended to limit this invention.

[0037] like Figure 1 As shown, this embodiment provides a fiber-oriented reinforced resin matrix composite molding equipment, which is arranged in sequence along the material processing and conveying direction as follows: long fiber positioning device 1, magnetic cap forming device 2, air drying and curing device 3, matrix mixing device 4, directional magnetic field device 5, magnetic cap desorption device 6, hot pressing device 7, and support platform 8. The system includes the following components: a long fiber positioning device 1 for screening, untangling, guiding, single-fiber positioning, and excess fiber recycling of long fiber raw materials; a magnetic cap forming device 2 for attaching temporary magnetic response media to both ends of the long fibers to form magnetic caps; a drying and curing device 3 for low-temperature drying and curing of the magnetic caps; a matrix mixing device 4 for mixing the long fibers with the matrix system after the magnetic caps have been cured at both ends, and transferring the mixed material to the molding mold 403; a directional magnetic field device 5 for applying a directional magnetic field to the capped long fiber / matrix system mixture in the molding mold 403, so that the long fibers are gradually adjusted from a disordered distribution state to an ordered state arranged along the target direction; a magnetic cap desorption device 6 for heating, softening, magnetically removing, and subsequently drying the magnetic caps at both ends of the long fibers after orientation; a hot pressing device 7 for hot pressing and curing the long fiber / matrix system mixture after orientation and removal of the magnetic caps; and a support platform 8 for installing, supporting, and positioning the above-mentioned functional devices to ensure the structural stability of the entire equipment during operation. Through the above structural arrangement, this invention integrates long fiber pretreatment, double-end capping, magnetic cap curing, mixing and molding, magnetic field orientation, magnetic cap removal, drying, and hot pressing into one process, which is beneficial to improving the consistency of long fiber orientation, molding efficiency, and the stability of the final composite material product. Specifically, this invention relates to "long fibers," which refers to discrete fibers suitable for single-strand positioning, end-capped magnetic response media attachment, magnetic field orientation, and subsequent hot pressing.

[0038] Figure 2A schematic diagram of the long fiber positioning device 1 in an embodiment of the present invention is shown. The long fiber positioning device 1 is located at the front end of the entire molding equipment and is mainly used for screening, guiding, single-fiber limiting and positioning, and recycling excess fibers of the input long fiber raw materials, and provides the posture basis for the subsequent double-end magnetic cap fixing process. The long fiber positioning device 1 mainly includes a feeding trough 107, a drum screen 106, a guide plate 105, a fiber positioning plate 101, a fixing platform 102, a push rod 103, a push rod seat 104, and a recycling box 108.

[0039] The feeding trough 107 is located at the feed end of the long fiber positioning device 1, serving to receive externally fed long fiber raw materials and guide them into the drum screen 106. The drum screen 106 is connected to the feeding trough 107 and is used to screen and untangle the long fiber raw materials, dispersing entangled fibers and removing unsuitable short fibers or impurities. The long fibers processed by the drum screen 106 fall onto the guide plate 105, which guides the dispersed long fibers along a predetermined direction to the fiber positioning plate 101. The fiber positioning plate 101 is the core positioning component of the long fiber positioning device 1. Its upper surface is provided with multiple positioning grooves arranged along a predetermined direction. Each positioning groove is used to accommodate a single long fiber and limit mutual interference between adjacent fibers. The structural length of the fiber positioning plate 101 along the axial direction of the long fiber is less than the length of the long fiber body, so that after the long fiber falls into the corresponding positioning groove, both ends of its axial direction extend beyond the fiber positioning plate 101. With this structural design, when the magnetic caps are dipped at both ends in sequence, the fiber end that has been fixed on one side of the magnetic cap will not come into contact with and adhere to the fiber positioning plate 101 again, which is conducive to the continuous and stable progress of the double-end magnetic cap fixing process.

[0040] Push rods 103 are respectively provided at the four lower corners of the fiber positioning plate 101. The four push rods 103 are distributed at the four corners of a rectangle and are respectively installed and positioned by corresponding push rod seats 104. In one embodiment, the push rods 103 are electric push rods, and the extension stroke and speed of each push rod 103 are independently adjusted by a controller to realize the deflection movement of the fiber positioning plate 101 in different directions. The four push rods 103 form a hinged engagement with the corresponding positions on the lower surface of the fiber positioning plate 101, so that the fiber positioning plate 101 can realize the deflection movement in different directions under the individual or coordinated extension and retraction of the four push rods 103.

[0041] The radial deflection is achieved by controlling two push rods 103 on the same side of the fiber positioning plate 101 in the width direction to extend synchronously, while two push rods 103 on the other side to shorten synchronously or remain stationary, causing the fiber positioning plate 101 to tilt around its long axis, with an tilt angle typically between 5 and 15°. At this time, long fibers that roll off the guide plate 105 onto the fiber positioning plate 101 roll towards the lower side under the action of gravity, preferentially falling into the positioning grooves on that side. Excess fibers that do not enter the positioning grooves continue to roll towards the lower side and enter the recycling box 108, thus achieving automatic recycling of excess fibers.

[0042] The axial deflection is achieved by controlling two push rods 103 at the same end of the fiber positioning plate 101 along its length to extend synchronously, while the two push rods 103 at the other end shorten synchronously or remain stationary, causing the fiber positioning plate 101 to tilt around its minor axis, with an tilt angle typically between 20-40°. At this time, each long fiber tilts along with the fiber positioning plate 101, with its lower end facing the corresponding forming groove 202, so that its end can contact and be dipped into the temporary magnetic response medium within the forming groove 202. After one end is dipped, the push rods 103 reverse their movement, causing the fiber positioning plate 101 to tilt to the other side, achieving dipping at the other end. The coordinated action of the four push rods 103 is automatically controlled by a preset program, ensuring that radial and axial deflections are executed sequentially according to the process order.

[0043] A recycling bin 108 is positioned on one side of the fiber positioning plate 101 to collect excess long fibers that do not fall into the positioning groove during the positioning process. After the long fibers enter the fiber positioning plate 101 via the guide plate 105, the fiber positioning plate 101 first deflects radially toward the side where the recycling bin 108 is located, allowing the long fibers to fill the groove under gravity and causing excess fibers to roll into the recycling bin 108. After the excess fibers are collected, the fiber positioning plate 101 then deflects to both sides along the fiber axis for subsequent magnetic cap fixation of both ends of the long fibers. A fixing platform 102 is positioned below the fiber positioning plate 101 and fixedly mounted on the support platform 8. The fixing platform 102 is mainly used to provide installation positioning and electrical connection for the push rod seat 104 and the push rod 103. By setting the fixing platform 102 as an independent installation and power and control connection base, the structural stability and control reliability when the four push rods 103 work together can be improved.

[0044] Preferably, the length of a single long fiber is 50-300 mm, more preferably 80-200 mm. The length of the long fiber is greater than the structural length of the fiber positioning plate 101 along the fiber axis, so that after the long fiber falls into the positioning groove, both ends of its axial direction extend beyond the fiber positioning plate 101, facilitating the sequential attachment of the magnetic response medium at both ends and subsequent desorption treatment. More preferably, the rotation speed of the drum screen 106 is 10-40 r / min, to balance the untangling and dispersion effect of the long fiber and the fiber integrity; the angle between the guide plate 105 and the horizontal plane is 20°-45°, to facilitate the smooth introduction of the long fiber into the fiber positioning plate 101 along the predetermined direction; the groove width of the positioning groove is preferably 1.1-2.0 times the diameter of the long fiber, and the center distance between adjacent positioning grooves is preferably 1.5-5.0 times the diameter of the long fiber, to facilitate single-fiber falling into the groove and reduce interference between adjacent long fibers.

[0045] Figure 3 A schematic diagram of the magnetic cap forming device 2 in an embodiment of the present invention is shown. The magnetic cap forming device 2 is located downstream of the long fiber positioning device 1 and is mainly used to sequentially attach temporary magnetic response media to both ends of the positioned long fiber, thereby forming magnetic caps at both ends of the long fiber that can be used for subsequent magnetic field orientation. The magnetic cap forming device 2 mainly includes a magnetic cap media chamber 201 and a forming groove 202. The magnetic cap media chamber 201 is used for storing, maintaining, and supplying the temporary magnetic response media, and is configured in two sets corresponding to the left and right sides to facilitate the sequential dipping operation at both ends of the long fiber. The forming groove 202 is connected to the magnetic cap media chamber 201 and is used to receive the temporary magnetic response media from the magnetic cap media chamber 201, serving as the working part for directly dipping the ends of the long fiber into the magnetic cap. Preferably, the forming groove 202 maintains a flow dynamic higher than the softening temperature of the temporary magnetic response media during operation to ensure that the ends of the long fiber can stably adhere and form end magnetic caps of relatively uniform size during contact.

[0046] In one embodiment, the operating temperature of the magnetic cap medium chamber 201 and the forming tank 202 can be 75-90°C, more preferably 78-85°C, to ensure that the temporary magnetic response medium maintains a stable flow dynamic and to ensure the consistency of the cap after end-coating. Furthermore, the mass ratio of stearic acid to carbonyl iron powder in the temporary magnetic response medium can be 1:2-1:6, more preferably 1:3-1:4.5, to balance the magnetic response capability, end-adhesion capability, and subsequent desorption properties of the magnetic cap.

[0047] The temporary magnetic response medium is preferably composed of stearic acid and carbonyl iron powder. Stearic acid serves as a carrier for end coating, adhesion, and curing into a cap, while carbonyl iron powder imparts a strong ferromagnetic response capability to the formed magnetic cap. On the one hand, the strong ferromagnetism of carbonyl iron powder is beneficial for the reliable traction and orientation of the long fiber ends in the subsequent magnetic orientation field. On the other hand, stearic acid can begin to soften at about 60-70°C, making it easier to soften, traction, and remove the cap in the subsequent magnetic cap desorption process, which helps to reduce the difficulty of cap removal and reduce residue. During operation, when the fiber positioning plate 101 carrying the long fiber moves to the corresponding station of the magnetic cap forming device 2, the fiber positioning plate 101 tilts to one side along the axial direction of the long fiber, causing one end of the long fiber to slide and contact the temporary magnetic response medium in the forming groove 202, which is in a liquid or semi-fluid state, thereby forming an initial magnetic cap at that end. Subsequently, the fiber positioning plate 101 tilts to the other side, causing the other end of the long fiber to contact the temporary magnetic response medium in the forming groove 202 on the other side and form the other end magnetic cap, thereby forming temporary magnetic response structures at both ends of the long fiber for subsequent magnetic field orientation. After the formation of the double-ended magnetic caps is completed, the fiber positioning plate 101 carrying the long fiber enters the subsequent air-drying and curing device 3 for uniform air-drying and curing treatment of the magnetic caps at both ends.

[0048] In summary, the magnetic cap forming device 2, through the cooperation of the magnetic cap medium chamber 201 and the forming tank 202, realizes the sequential dipping of the two ends of the long fiber with the temporary magnetic response medium and the formation of the magnetic cap; and by using stearic acid and carbonyl iron powder to form the temporary magnetic response medium, the formed magnetic cap has both good magnetic response capability and can soften and desorb under subsequent lower temperature conditions, thus taking into account both the orientation requirements of the preceding process and the removal requirements of the subsequent process.

[0049] Figure 4A schematic diagram of the air-drying and curing device 3 in an embodiment of the present invention is shown. The air-drying and curing device 3 is located downstream of the magnetic cap forming device 2 and is mainly used for low-temperature air-drying and curing of the magnetic caps already formed at both ends of the long fibers, so that the double-ended magnetic caps maintain a stable shape during subsequent mixing and magnetic field orientation processes. The air-drying and curing device 3 mainly includes an air-drying mechanism 301 and an air-drying mechanism base 302. The air-drying mechanism base 302 is used to support and install the air-drying mechanism 301, and the air-drying mechanism 301 is used to output low-temperature airflow and air-dry and cure the magnetic caps at the ends of the long fibers. In one embodiment, the air outlet of the air-drying mechanism 301 is arranged symmetrically vertically or horizontally, respectively aligned with the two protruding areas of the long fibers on the fiber positioning plate 101, so that the low-temperature airflow is concentrated on the magnetic cap area instead of directly blowing on the middle of the long fibers, avoiding displacement or deflection of the long fibers during the air-drying process. During operation, the long fibers with double-ended magnetic caps are formed and enter the corresponding station of the air-drying and curing device 3. Under the action of the air-drying mechanism 301, the temporary magnetic response medium attached to both ends of the long fibers gradually solidifies, thereby forming stable magnetic caps at both ends of the long fibers, providing conditions for subsequent mixing and magnetic orientation processes.

[0050] In one embodiment, the air temperature of the airflow output from the drying mechanism 301 can be 15-35°C, more preferably 20-30°C; the air velocity can be 1-5 m / s, more preferably 2-4 m / s; and the drying time can be 10-60 s, more preferably 20-40 s, so that the double-ended magnetic cap can be stably cured without significant morphological collapse. Low-temperature drying avoids the softening or even flow of stearic acid at higher temperatures, which could lead to deformation or detachment of the magnetic cap. The low-speed airflow at around room temperature can remove heat from the magnetic cap medium, promoting the cooling and crystallization of stearic acid and fixing the distribution of carbonyl iron powder. This allows the magnetic cap to be stably formed without flow, collapse, or detachment, while also preserving its geometric shape.

[0051] Figure 5A schematic diagram of the matrix mixing device 4 in an embodiment of the present invention is shown. The matrix mixing device 4 is located downstream of the air-drying curing device 3 and is mainly used to mix the long fibers that have completed double-ended magnetic cap curing with the matrix system, and to transfer the mixed material to the molding die 403. The matrix system is preferably a thermosetting resin matrix system suitable for hot-press curing. The matrix mixing device 4 mainly includes a mixing chamber 401, a stirring paddle 402, and a molding die 403. The mixing chamber 401 is used to contain the long fibers and the various components of the thermosetting resin matrix system. Each component may include thermosetting resin components and optional fillers, additives, and / or premixed components. The stirring paddle 402 is used to stir and mix the materials in the mixing chamber 401. The molding die 403 is used to receive the mixed material and serves as a supporting component for subsequent magnetic orientation, magnetic cap desorption, and hot-press molding. During operation, the capped long fibers, after being processed at the previous station, are added to the mixing chamber 401 and mixed together with the components of the matrix system. After the stirring paddle 402 is activated, the long fibers and the matrix system are thoroughly mixed to form a relatively uniform mixture. After mixing, the mixture is transferred to the molding die 403 for subsequent orientation treatment by the directional magnetic field device 5. During the mixing and orientation stages, the matrix system is preferably in a slurry, paste, or flowable premixed state so that the capped long fibers can complete mixing, mold entry, and subsequent magnetic field orientation within the matrix system. In the subsequent drying stage after the magnetic caps are desorbed, the matrix system is gradually transformed into a powder state suitable for subsequent hot pressing.

[0052] In one embodiment, the matrix system can be a thermosetting resin matrix system suitable for hot pressing and curing. The thermosetting resin component can be one or more of phenolic resin, epoxy resin, and unsaturated polyester resin, and fillers, curing agents, lubricants, toughening agents, or other additives can be added according to the performance requirements of the target product. When the prepared composite material is used in the field of friction materials, one or more of calcium carbonate and barium sulfate can be further selected as fillers. In other application scenarios of thermosetting resin composite materials, a premixed thermosetting resin system adapted to long fibers can also be used.

[0053] To further illustrate, two specific matrix system formulation examples are provided below: Formulation Example 1: 30 parts by weight of thermoplastic phenolic resin, 3 parts by weight of hexamethylenetetramine curing agent, 50 parts by weight of calcium carbonate, and 5 parts by weight of graphite lubricant were added to mixing chamber 401 and premixed evenly to obtain a slurry or flowable premixed matrix system (which was subsequently gradually transformed into a powder state suitable for hot pressing after decapping and drying treatment); then 10 parts by weight of 80 mm long fiber were added and slowly mixed at a stirring speed of 40 r / min for 5 minutes to ensure that the fiber was evenly dispersed in the matrix system without damaging the magnetic caps at both ends.

[0054] Formulation Example 2: 100 parts by weight of epoxy resin, 50 parts by weight of amine curing agent and 50 parts by weight of filler are premixed into a flowable paste matrix system; then 15 parts by weight of fiber with a length of 100 mm are added and mixed evenly for 3 minutes at a stirring speed of 80 r / min to obtain a flowable fiber / matrix mixture.

[0055] Figure 6 A schematic diagram of the directional magnetic field device 5 in an embodiment of the present invention is shown. The directional magnetic field device 5 is located downstream of the matrix mixing device 4 and is mainly used to apply a directional magnetic field to the long fiber / matrix system mixture in the molding die 403, causing the capped long fibers to gradually transform from a disordered distribution state to an ordered state arranged along the target direction. The directional magnetic field device 5 mainly includes a Helmholtz coil mechanism 501 and a coil support plate 502. The coil support plate 502 is used to support and install the Helmholtz coil mechanism 501, which generates a relatively uniform directional magnetic field within its working area. During operation, the molding die 403 carrying the mixture is placed within the working area of ​​the Helmholtz coil mechanism 501. After the Helmholtz coil mechanism 501 is energized, it forms a directional magnetic field. Because the long fibers have magnetic caps at both ends, under the action of the magnetic field, each long fiber gradually deflects and rotates, eventually tending to align in the same direction, thereby achieving the directional distribution of the long fibers in the matrix material.

[0056] In one embodiment, the directional magnetic field strength generated by the Helmholtz coil mechanism 501 can be 20-80 mT, more preferably 30-60 mT; the magnetic field application time can be 10-120 s, more preferably 15-60 s. Specific parameters can be adjusted according to the length of the long fiber, the magnetic response capability of the magnetic cap, and the viscosity of the matrix system.

[0057] Figure 7 A schematic diagram of the magnetic cap removal device 6 in an embodiment of the present invention is shown. The magnetic cap removal device 6 is located downstream of the directional magnetic field device 5 and is mainly used to soften, magnetically remove, and subsequently dry the magnetic caps at both ends of the long fibers after orientation. The magnetic cap removal device 6 mainly includes a lifting mechanism 601, a strong magnetic plate 602, and a heating plate 603. The lifting mechanism 601 drives the strong magnetic plate 602 to move up and down. A pair of strong magnetic plates 602 are respectively arranged on the outer sides of both ends of the forming mold 403 and are parallel to the corresponding end areas of the forming mold 403. A pair of lifting mechanisms 601 are respectively connected to the corresponding strong magnetic plates 602 and are used to drive the corresponding strong magnetic plates 602 to move vertically closer to or further away from the forming mold 403, so as to symmetrically remove the magnetic caps at both ends.

[0058] To avoid the molding mold 403 obstructing the magnetic cap removal process, the molding mold 403 is made of non-ferromagnetic or weakly magnetic material. This ensures that the molding mold 403 does not move with the strong magnetic plate 602 during the magnetic cap removal process, nor does it significantly attract or shield the magnetic field generated by the strong magnetic plate 602. The magnetic cap contains carbonyl iron powder, which retains its magnetic responsiveness after softening by heating. When the strong magnetic plate 602 approaches the end region of the molding mold 403, it forms a non-uniform magnetic field in the area where the magnetic cap is located. Under the action of the magnetic field gradient, the softened magnetic cap generates a magnetic gradient pull towards the strong magnetic plate 602 and migrates along the edge of the molding mold 403 end or the cap removal avoidance area towards the strong magnetic plate 602. Subsequently, the strong magnetic plate 602 moves upward under the drive of the lifting mechanism 601, and the magnetic cap attracted to the surface of the strong magnetic plate 602 moves upward synchronously with the strong magnetic plate 602, thereby detaching from the molding mold 403 and being carried out for collection. Since the molding die 403 remains stationary and mainly supports and limits the middle part of the long fiber and the resin matrix system, it will not hinder the magnetic removal of the softening magnetic cap, nor will it damage the orientation state that the long fiber has already formed.

[0059] Heating plate 603 is used to heat the mixture inside molding die 403. During operation, the magnetic cap contains a high proportion of carbonyl iron powder, which has excellent ferromagnetic response characteristics. In the non-uniform magnetic field generated by strong magnetic plate 602, it will be subjected to a magnetic attraction force pointing in the direction of strong magnetic plate 602. When heating plate 603 heats the material to about 70°C, the stearic acid component in the magnetic cap softens, and the adhesion between the magnetic cap and the end of the long fiber decreases significantly. At this time, the magnetic attraction force exerted by the nearby strong magnetic plate 602 on the magnetic cap area is much greater than the residual adhesion force between the magnetic cap and the long fiber in the softened state and the resistance of the surrounding matrix material. Therefore, the magnetic cap detaches from the fiber end under the action of net magnetic attraction force. After being attracted by strong magnetic plate 602, lifting mechanism 601 drives strong magnetic plate 602 to rise, so that the removed magnetic cap is removed from the matrix material in molding die 403. Furthermore, the magnetic cap medium adsorbed on the surface of the strong magnetic plate 602 can be periodically scraped off into the recycling container by a scraper mechanism or by briefly cutting off the electromagnetic attraction (when the strong magnetic plate 602 is an electromagnet).

[0060] After the magnetic cap is removed, the heating plate 603 continues to maintain a constant temperature to further dry the mixture in the molding die 403. The heating temperature during the drying stage can be increased to 80-100 ℃, and the heating time is 30-60 minutes, or the material can be continuously heated under ventilation until the moisture content is less than 5% or the required powder state is reached. This allows the slurry or paste matrix system used for mixing and magnetic field orientation to gradually dry and transform into a powder state suitable for subsequent hot pressing. During this process, since the long fibers are embedded in the matrix system, the geometric constraints of the molding die 403, the viscous damping of the matrix system, and the local coating effect jointly inhibit the long fibers from deflecting freely again. Moreover, the cap removal process mainly occurs in the fiber end regions, so the long fibers can still maintain their existing orientation state in situ.

[0061] In one embodiment, when a pair of strong magnetic plates 602 are close to the end region of the long fiber, the minimum distance between them and the corresponding fiber end can be 1-10 mm, more preferably 2-5 mm; the time for a single magnetic cap removal action can be 1-10 s, more preferably 2-6 s, so as to reduce disturbance to the main area of ​​the substrate material while ensuring reliable detachment of the magnetic cap. Furthermore, the strong magnetic plates 602 can be made of neodymium iron boron permanent magnets or electromagnets, and their surface magnetic field strength is preferably not less than 0.3T, to ensure sufficient magnetic attraction force on the magnetic cap area under a distance of several millimeters.

[0062] Figure 8A schematic diagram of the hot pressing device 7 in an embodiment of the present invention is shown. The hot pressing device 7 is located downstream of the magnetic cap removal device 6 and is mainly used for heating, pressing, and curing the long fiber / matrix system mixture after orientation and removal of the magnetic cap, to obtain a target-oriented reinforced thermosetting resin-based composite material product. The hot pressing device 7 mainly includes a hot pressing power mechanism 701, a hot pressing mechanism support 702, and a cover plate 703. The hot pressing mechanism support 702 is used to support and install the hot pressing power mechanism 701. The hot pressing power mechanism 701 is a hot pressing execution unit integrating pressurization and heating functions, and it is equipped with a heating unit inside to provide the pressure required for downward pressing and output the heat required for molding. The cover plate 703 is installed below the hot pressing power mechanism 701 and is adapted to the size of the molding die 403, used to transfer heat and pressure to the material during the pressing process. In one embodiment, the hot pressing power mechanism 701 is a hydraulic cylinder or a pneumatic cylinder, whose piston rod passes through a hole in the middle of the hot pressing mechanism support 702 and connects to the cover plate 703. The heating unit is embedded inside the cover plate 703 or disposed above the cover plate 703, and heat is conducted to the material through the contact surface of the cover plate 703. During operation, the molding die 403 carrying the material enters the corresponding station of the hot pressing device 7, the hot pressing power mechanism 701 is activated and drives the cover plate 703 to move downward. Under the combined action of heating and pressurization, the matrix system completes compaction, consolidation and curing, and finally obtains a long fiber oriented reinforced thermosetting resin matrix composite product. In one embodiment, the hot pressing temperature can be 120-200℃, the hot pressing pressure can be 2-20MPa, and the holding time can be 1-30 min. The specific parameters can be adjusted according to the curing characteristics of the thermosetting resin matrix system used.

[0063] Figure 9A schematic diagram of the support platform 8 in an embodiment of the present invention is shown. The support platform 8 serves as the foundation for the entire molding system and is mainly used for the installation, support, and positioning of the aforementioned functional devices. The support platform 8 mainly includes a support table 801, a guide rail 802, and a guide rail bracket 803. The support table 801 is used to support the long fiber positioning device 1, the magnetic cap forming device 2, the air drying and curing device 3, the matrix mixing device 4, the directional magnetic field device 5, the magnetic cap desorption device 6, and the hot pressing device 7. The guide rail bracket 803 is set on the support table 801, and the guide rail 802 is installed on the guide rail bracket 803. It is used to guide and limit the transfer of the fiber positioning plate 101 and the forming mold 403 at different process stages. Specifically, between the long fiber positioning device 1, the magnetic cap forming device 2, and the air drying and curing device 3, the guide rail 802 is mainly used to guide and limit the stage transfer of the fiber positioning plate 101. Between the matrix mixing device 4, the directional magnetic field device 5, the magnetic cap desorption device 6, and the hot pressing device 7, the guide rail 802 is mainly used to guide and limit the stage transfer of the forming mold 403. In one embodiment, the above-mentioned workstation transfer is completed manually. The operator can push, slide and position the fiber positioning plate 101 or the molding die 403 along the guide rail 802 to realize the phased connection between each process.

[0064] Please refer to the working process of the fiber-oriented reinforced resin matrix composite material molding equipment in this embodiment. Figures 1 to 9 In this embodiment, the transfer between each workstation is not limited to a fully automatic drive mode. The fiber positioning plate 101 and the forming mold 403 can be transferred and positioned between adjacent workstations along the guide rail 802 with manual assistance. During operation, the long fiber raw material to be processed is first introduced into the drum screen 106 through the feed trough 107. After being screened and untangled by the drum screen 106, the long fibers fall onto the fiber positioning plate 101 along the guide plate 105. Under the action of the four push rods 103, the fiber positioning plate 101 first undergoes radial deflection, causing the long fibers to fall into the corresponding grooves one by one, and the excess fibers roll into the recycling box 108, completing the limiting positioning of the long fibers and the recycling of excess fibers. Subsequently, the fiber positioning plate 101 deflects sequentially to both sides along the axial direction of the long fibers, so that the two ends of the long fibers contact the temporary magnetic response medium in the corresponding forming grooves 202 on the left and right, thereby completing the formation of double-end magnetic caps. After that, the fiber positioning plate 101 enters the corresponding station of the air drying and curing device 3 to perform uniform air drying and curing treatment on the magnetic caps at both ends of the long fibers, and finally forms stable double-end magnetic caps.

[0065] After the long fibers with double-ended caps are completed, they enter the matrix mixing device 4 and are mixed with the matrix system in the mixing chamber 401 in the slurry, paste or flowable premixed state. The mixture is stirred evenly by the stirring paddle 402 and the mixed material is transferred to the molding die 403. Then, the molding die 403 enters the directional magnetic field device 5. Under the action of the directional magnetic field generated by the Helmholtz coil mechanism 501, the capped long fibers are gradually adjusted from the initial disordered state to the unidirectional alignment state.

[0066] After the long fibers are oriented, the molding die 403 enters the magnetic cap desorption device 6. The heating plate 603 first heats the material, preferably to about 70°C, to soften the stearic acid component in the magnetic cap. Then, the strong magnetic plate 602 approaches the two ends of the long fibers with the help of the lifting mechanism 601. Since the magnetic cap is subjected to a non-uniform magnetic field at this time, the softened magnetic cap gathers to both sides under the action of magnetic attraction and detaches from the ends of the long fibers, adsorbing onto the surface of the strong magnetic plate 602. The lifting mechanism 601 then drives the strong magnetic plate 602 to rise, so that the magnetic cap is taken out of the matrix material. After the cap is removed, the heating plate 603 continues to heat at a constant temperature, raising the temperature to 80-100°C for subsequent drying, so that the original slurry state is gradually dried into a powder state, while the long fibers remain in place and maintain their original orientation state.

[0067] Finally, the processed material enters the hot pressing device 7, where it undergoes hot pressing and curing under the action of the hot pressing power mechanism 701 and the cover plate 703, ultimately obtaining a long fiber oriented reinforced resin-based composite material product. The above processes are sequentially linked, forming a continuous preparation process from long fiber screening and positioning, double-end capping, air drying and curing, mixing and molding, magnetic field orientation, magnetic cap desorption, drying to hot pressing.

[0068] To further illustrate the state changes of long fibers in each key process in this embodiment, combined with Figures 10 to 13 Please provide an explanation. Figure 10 The diagram shows the limiting and positioning state after the long fiber falls into the groove on the surface of the fiber positioning plate 101. At this time, each long fiber is contained in the corresponding groove, and both ends of the long fiber extend out of the fiber positioning plate 101. Figure 11 The diagram shows the fiber positioning plate 101 deflecting to the left and right sides along the fiber axis during the formation of the long fiber double-end magnetic cap. This diagram illustrates the working condition of the long fiber being dipped towards the forming groove 202 at one end and the other end, and is used to explain the posture change during the formation of the long fiber double-end magnetic cap. Figure 12 The experiment shows that long fibers with double-ended magnetic caps, after being mixed with a matrix material, gradually change from an irregular orientation to a unidirectional alignment under the influence of a magnetic field, and retain their orientation even after the magnetic caps are removed.

[0069] Figure 13A schematic diagram of the finished product structure of long fiber reinforced resin matrix composite material is shown. In one embodiment, a long fiber oriented preform layer is formed after a single magnetic field orientation, cap removal, and drying treatment. When a multi-layer oriented reinforced structure is required, the above-mentioned orientation preformation process can be repeated to obtain multiple long fiber oriented preform layers. The multiple long fiber oriented preform layers are stacked in the same direction, cross direction, or preset angle, and then subjected to re-pressing thermosetting to form a multi-layer oriented reinforced resin matrix composite material product, wherein the long fibers in each layer maintain an orderly and relatively uniform oriented distribution.

[0070] Figure 14 The overall molding process of the fiber-oriented reinforced resin matrix composite material in this embodiment is summarized in a flowchart. The process mainly includes a magnetic cap prefabrication stage, an orientation arrangement stage, and a cap removal molding stage: First, the long fibers are pretreated and individually positioned. The fibers are then deflected to the left and right sides along the fiber axis by the fiber positioning plate 101, so that the two ends of the long fibers are sequentially coated with a temporary magnetic response medium. After air drying and curing, a double-ended magnetic cap is formed. Subsequently, the magnetically responsive long fibers are mixed with the matrix system and introduced into the molding mold 403. Under the action of the directional magnetic field, the long fibers are oriented in the same direction within the mold. Finally, the oriented material is subjected to magnetic cap heating and softening, magnetic adsorption and desorption, subsequent drying, and hot pressing curing to obtain the oriented long fiber reinforced resin matrix composite material product.

[0071] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A molding equipment for fiber-oriented reinforced resin-based composite materials, characterized in that, It includes a support platform, and a long fiber positioning device, a magnetic cap forming device, an air drying and curing device, a matrix mixing device, a directional magnetic field device, a magnetic cap desorption device, and a hot pressing device, which are sequentially arranged on the support platform along the material processing and conveying direction. The long fiber positioning device is used for screening, untangling, guiding, positioning individual fibers, and recovering excess long fibers from long fiber raw materials. The magnetic cap forming device is used to attach temporary magnetic response media to the axial end regions of the positioned long fiber in sequence, so as to form magnetic caps for subsequent magnetic field orientation in the axial end regions of the long fiber. The air-drying and curing device is used to air-dry and cure the magnetic caps; The matrix mixing device is used to mix the long fibers that have been cured with double-ended magnetic caps with the resin matrix system, and to introduce the mixed material into the molding die. The directional magnetic field device is used to apply a directional magnetic field to the material in the molding die, so that the long fibers are adjusted from a disordered distribution state to an ordered state arranged along the target direction; The magnetic cap desorption device is used to heat and soften the magnetic caps at both ends of long fibers after the fibers have been oriented, and then magnetically desorb them so that the magnetic caps can be separated from and removed from the long fibers. The material after the magnetic caps have been removed is then dried. The hot pressing device is used to hot press and cure the long fiber / resin matrix system mixture that has been oriented and whose magnetic caps have been removed, in order to obtain fiber-oriented reinforced resin matrix composite products. The directional magnetic field device includes a Helmholtz coil mechanism and a coil support plate. The coil support plate is used to support and install the Helmholtz coil mechanism, which is used to generate a directional magnetic field in its working area. The magnetic field strength of the directional magnetic field is 20-80 mT, and the magnetic field is applied for 10-120 s. The magnetic cap removal device includes a lifting mechanism, a pair of strong magnetic plates and a heating plate respectively set on the outer sides of both ends of the molding mold. The strong magnetic plates move vertically closer to or further away from the molding mold under the drive of the lifting mechanism, so that after the magnetic cap softens, it can be adsorbed and removed by a non-uniform magnetic field and transferred to the surface of the strong magnetic plate for collection. When the strong magnetic plate is close to the end area of ​​the long fiber, the minimum distance between it and the corresponding end of the long fiber is 1-10 mm, and the time for a single magnetic cap removal is 1-10 s; The hot pressing device includes a hot pressing power mechanism, a hot pressing mechanism support, and a cover plate. The support of the hot pressing mechanism is set on a support platform. The hot pressing power mechanism and the cover plate are respectively set on the upper and lower sides of the hot pressing mechanism support and are linked to each other, so that the hot pressing power mechanism drives the cover plate to apply pressure to the material in the forming mold. The hot pressing temperature is 120-200℃, the hot pressing pressure is 2-20MPa, and the holding time is 1-30 min.

2. The fiber-oriented reinforced resin-based composite material molding equipment according to claim 1, characterized in that, The long fiber positioning device includes a fixed platform that is slidably connected to a support platform via a guide rail. A push rod seat is installed on the fixed platform. A telescopic push rod is installed inside the push rod seat. The top ends of multiple sets of push rods are hinged together to support a fiber positioning plate. The multiple sets of push rods are configured to extend and retract individually or in conjunction to drive the fiber positioning plate to achieve radial deflection and deflection along the long fiber axis. The upper surface of the fiber positioning plate is provided with multiple positioning grooves arranged in a predetermined direction to accommodate a single long fiber and limit the mutual interference between adjacent long fibers. The structural length of the fiber positioning plate along the axial direction of the long fiber is less than the length of the long fiber body, so that after the long fiber falls into the corresponding positioning groove, both ends of its axial direction extend beyond the corresponding end face of the fiber positioning plate. The long fiber positioning device also includes a feed trough, a drum screen, a guide plate and a recycling box arranged sequentially along the material flow direction. The end of the guide plate extends above the fiber positioning plate and is used to guide the long fibers after being screened and untangled by the drum screen to the fiber positioning plate. The radial deflection of the fiber positioning plate is used to make the long fibers fill the positioning grooves first and allow the excess long fibers that do not enter the positioning grooves to enter the recycling box. The deflection of the fiber positioning plate along the axial direction of the long fibers is used to make the two ends of the long fibers tilt toward the magnetic cap medium chamber of the subsequent magnetic cap forming device. The fixed platform is slidably connected to the support platform via guide rails and is used to transfer fiber positioning plates between adjacent workstations.

3. A fiber-oriented reinforced resin-based composite material molding device according to claim 2, characterized in that, The length of a single long fiber is 50-300 mm; the rotation speed of the drum screen is 10-40 r / min; the angle between the guide plate and the horizontal plane is 20-45°; the width of the positioning groove is 1.1-2.0 times the diameter of the long fiber; the center distance between adjacent positioning grooves is 1.5-5.0 times the diameter of the long fiber.

4. A fiber-oriented reinforced resin-based composite material molding device according to claim 2, characterized in that, The magnetic cap forming device includes two sets of magnetic cap medium chambers arranged on the left and right sides respectively, and a forming groove communicating with the magnetic cap medium chambers; The magnetic cap medium chamber is used to store and supply the temporary magnetic response medium for forming the magnetic cap, and the forming groove is used to receive the temporary magnetic response medium and to allow the ends of long fibers to be dipped to form the magnetic cap. The working temperature of both the magnetic cap medium chamber and the forming tank is maintained at 75-90℃, so that the temporary magnetic response medium remains in a liquid state in the forming tank; The temporary magnetic response medium is composed of stearic acid and carbonyl iron powder, and the mass ratio of stearic acid to carbonyl iron powder is 1:2-1:

6.

5. A fiber-oriented reinforced resin-based composite material molding device according to claim 1, characterized in that, The air-drying and curing device includes an air-drying mechanism and an air-drying mechanism base. The air-drying mechanism is used to output low-temperature airflow to air-dry and cure the magnetic caps at both ends of the long fiber. The temperature of the low-temperature airflow in the air-drying and curing device is 15-35℃, the wind speed is 1-5 m / s, and the air-drying time is 10-60s.

6. A fiber-oriented reinforced resin-based composite material molding device according to claim 1, characterized in that, The mixing chamber is used to contain the long fiber and resin matrix system that has been cured with double-ended magnetic caps; The agitator is located inside the mixing chamber and is used to agitate and mix the materials inside the mixing chamber, so that the long fibers and the resin matrix system are fully mixed to form a uniform long fiber / resin matrix system mixture. The molding die is used to receive the long fiber / resin matrix system mixture and serves as a supporting component for subsequent directional magnetic field treatment, magnetic cap desorption, and hot pressing. The forming mold slides with the guide rail set on the support platform to carry the material to flow between each station; The resin matrix system is a thermosetting resin matrix system suitable for hot pressing and curing, and is in a flowable premixed state during the mixing and orientation stages, with a low viscosity of 5-10 Pa·s.

7. A method for molding fiber-oriented reinforced resin-based composite materials, characterized in that, A fiber-oriented reinforced resin-based composite material molding device based on any one of claims 1-6 includes the following steps: S1. Non-magnetic long fiber raw materials are introduced into the long fiber positioning device, and the fiber positioning plate is driven to deflect radially by 5-15°. After screening, unwinding and guiding, the long fibers fall into the positioning grooves of the fiber positioning plate one by one. At the same time, the excess long fibers that do not enter the positioning grooves are recycled into the recycling box. After filling, the fiber positioning plate is in a horizontal state. S2. Drive the fiber positioning plate to deflect 20-40° to one side along the long fiber axis, so that one end of the long fiber contacts the temporary magnetic response medium in the liquid or semi-fluid dynamic state in the forming groove on the corresponding side to form an initial magnetic cap. Then deflect 20-40° to the other side after leveling, so that the other end of the long fiber contacts the temporary magnetic response medium in the forming groove on the other side to form another magnetic cap, thereby forming magnetic caps at both ends of the long fiber. S3. The long fibers forming the magnetic cap are fed into the air drying and curing device to air dry and cure the magnetic cap, so that it reaches a solid state that can support subsequent glue application and mixing without deformation or falling off. S4. Mix the long fibers that have been cured with the magnetic cap with the resin matrix system, and then pour the mixed material into the molding die. S5. Place the molding die in the working area of ​​the directional magnetic field device and apply a directional magnetic field to the long fiber / resin matrix system mixture with magnetic cap in the molding die. When the directional magnetic field is applied, the resin matrix system is in a low viscosity state of 5-10 Pa·s, causing the long fibers to rotate and orient under the action of the magnetic field, changing from a disordered distribution state to an ordered state arranged along the target direction. S6. After the long fibers are oriented, the material in the molding die is heated to the temperature that softens the magnetic caps using a heating plate. Then, the magnetic caps at both ends of the long fibers are symmetrically removed using a strong magnetic plate. The magnetic caps are transferred to the surface of the strong magnetic plate and collected. Then, the material is heated and dried to gradually change the resin matrix system from a flowable premixed state to a powder state suitable for hot pressing. S7. After the material has been decapped and dried, it is hot-pressed and cured to obtain fiber-oriented reinforced resin-based composite material products.

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