A continuous forming equipment for carbon fiber prepreg-stainless steel ultrathin fiber-reinforced metal laminates

Abstract

This invention relates to the field of fiber-metal laminate manufacturing technology, and particularly to a continuous forming equipment for carbon fiber prepreg-stainless steel ultrathin strip fiber-metal laminates. The invention comprises, sequentially along the material travel direction on a frame, an unwinding system, a preheating system, a lamination and compaction system, a cooling and shaping system, and a winding system. The lamination and compaction system, along the material travel direction, includes a pre-compacting roller system and a main compaction roller pair. The main compaction roller pair consists of upper and lower heated and pressurized rollers, with paired embossed textures on the roller surfaces. The winding system includes an upper winding roller and a lower winding roller, with the roller gap between them serving as the profile output port. This invention, through a synergistic "thermal-mechanical" process, rapidly and continuously composites thermoplastic carbon fiber prepreg with stainless steel ultrathin strip into profiles, achieving a significant improvement in production efficiency and product performance.

Description

Technical Field

[0001] This invention relates to the field of fiber metal laminate preparation technology, and in particular to a continuous forming equipment for carbon fiber prepreg-stainless steel ultrathin strip fiber metal laminate. Background Technology

[0002] Carbon fiber composite laminates (FMLs) made of metals (such as stainless steel) have broad application prospects in aerospace, electronics, and other fields due to their superior performance in terms of lightweighting, functionalization, and production efficiency. Specifically, carbon fiber provides extremely high strength and modulus, while ultra-thin stainless steel strips contribute toughness and ductility, achieving a synergistic effect of "1+1>2" and demonstrating outstanding performance in lightweighting. Moreover, the fiber layers can effectively "bridge" and prevent crack propagation, resulting in a fatigue life far exceeding that of single metal materials. They are also insensitive to damage such as impacts and dents, and can inhibit further damage propagation. Their polymer matrix and interlayer interfaces can effectively absorb vibration energy, providing better vibration damping and noise reduction than pure metal structures.

[0003] Despite the promising prospects of this material, a series of severe challenges and shortcomings remain in its transition from laboratory to industrial continuous production. Carbon fiber composites and stainless steel are inherently incompatible materials with vastly different coefficients of thermal expansion, and their bonding relies primarily on physical-mechanical interlocking, with relatively weak chemical bonding. In traditional autoclave or flat-plate hot-pressing processes, the laminate interface is prone to failure due to thermal stress after high- and low-temperature cycling, leading to delamination and reduced strength. Existing processes and equipment are mostly intermittent batch processing, resulting in low production efficiency and high costs, making it difficult to meet the needs of large-scale applications. Therefore, there is an urgent need for a device that can achieve rapid continuous production, effectively improve interfacial bonding, and simultaneously manufacture laminates with complex topological cross-sections. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a continuous forming equipment for carbon fiber prepreg-stainless steel ultrathin strip fiber metal laminate. It replaces the traditional intermittent autoclave with an integrated and continuous thermo-mechanical synergistic process to quickly and continuously composite thermoplastic carbon fiber prepreg with stainless steel ultrathin strip into composite materials, thereby achieving a leapfrog improvement in production efficiency and product performance.

[0005] To solve the above technical problems, the present invention adopts the following technical solution: a continuous forming equipment for carbon fiber prepreg-stainless steel ultra-thin fiber metal laminate, including a frame, on which an unwinding system, a preheating system, a lamination and compaction system, a cooling and shaping system and a winding system are arranged sequentially along the material travel direction.

[0006] The unwinding system includes an upper unwinding roller and a lower unwinding roller. The gap between the upper and lower unwinding rollers serves as the material inlet. The upper and lower unwinding rollers feed stainless steel ultrathin strips or carbon fiber prepreg. The preheating system includes a preheating roller system and preheating sources. Preheating sources are symmetrically arranged vertically at the gaps in the preheating roller system. The preheating sources do not contact the material, and the material forms a laminated material after passing through the preheating system. The lamination and compaction system consists of a precompacting roller system and a main compacting roller pair arranged sequentially along the material's travel direction. The precompacting roller system uses smooth-surfaced heated and pressurized rollers. The main compaction roller is responsible for the initial compaction and guidance of the preheated laminated material. The main compaction roller consists of two heating and pressure rollers, one above the other. The rollers of the two heating and pressure rollers are provided with paired embossed patterns to complete the pressing of the laminated material and form a high-temperature laminated material. The cooling and shaping system includes a water-cooled roller system, which consists of multiple rollers with internal cooling media. This system allows the high-temperature laminated material to be cooled in a controllable and uniform manner to complete the shaping. The winding system includes an upper winding roller and a lower winding roller. The roller gap between the upper winding roller and the lower winding roller is the profile output port.

[0007] The roll gap centerlines formed by the upper and lower parts of the unwinding system, preheating system, lamination and compaction system, cooling and shaping system, and winding system are on the same centerline.

[0008] Preferably, the upper unwinding roller and the lower unwinding roller each include at least one.

[0009] Preferably, the preheating source is an infrared heater or a hot air nozzle.

[0010] Preferably, the main compaction roller pair is a detachable structure, and the embossing shape on the roller surface of the main compaction roller pair is set as required.

[0011] Preferably, the embossing shape on the main compaction roller surface includes a corrugated shape for forming alternating peaks and troughs, a trapezoidal shape for forming trapezoidal reinforcing ribs, and a triangular shape for forming triangular reinforcing ribs.

[0012] Preferably, the main compaction roller has an integrated heating system that controls the roller surface temperature within the range of 300℃-450℃.

[0013] Preferably, both the pre-compacting roller system and the main compacting roller pair are equipped with a pressurization system that provides a linear pressure of 20t-50t.

[0014] More preferably, the temperature and pressure of the main compaction roller pair are higher than the temperature and pressure of the precompaction roller system.

[0015] The beneficial effects of this invention are as follows:

[0016] 1. It achieves continuous and efficient production. Traditional lamination processes are mostly segmented or intermittent (such as autoclaves), resulting in long production cycles and low efficiency. The device in this invention achieves uninterrupted production from raw materials to formed laminates through a continuous process of unwinding-preheating-lamination-cooling-rewinding, greatly improving production capacity and making it suitable for large-scale industrial applications.

[0017] 2. High interfacial bonding strength. Preheating the laminated materials using a non-contact preheating source softens the resin in the prepreg, reducing the material's molding resistance. The combination of a pre-compacting roller system and a main compacting roller pair allows the pre-compacting roller system to first expel interlayer gas, initiate bonding, and provide guidance. The main compacting roller pair then applies high pressure and a specific temperature. The high temperature melts and flows the thermoplastic resin, while the high pressure forces the molten resin to penetrate the microstructure of the surface-treated stainless steel, forming a strong mechanical interlock. This gradient compaction method effectively reduces defects such as air bubbles and insufficient adhesive, ensuring strong interfacial bonding.

[0018] 3. Precise molding and structural controllability. The main compaction roller pair is detachable, and the embossing shape on the roller surface can be set according to requirements. By replacing roller pairs with different embossing patterns, different reinforcing rib structures can be directly formed on the laminate, realizing integrated manufacturing of structure and function, and enabling customized production of laminates with different mechanical properties. The resulting corrugated, trapezoidal, and other three-dimensional structures have higher bending and peel resistance, effectively redistributing and mitigating interfacial thermal stress caused by mismatch in coefficients of thermal expansion and contraction, thereby significantly improving the product's resistance to high and low temperature cycling.

[0019] 4. Stable dimensional and internal stress control. After lamination, the material is in a high-temperature state. Direct winding will lead to deformation and residual stress. The water-cooled roller system achieves uniform and controllable cooling through internal cooling medium, which can effectively "freeze" the formed shape, reduce warpage deformation, stabilize product dimensions, and reduce residual internal stress.

[0020] 5. By changing the unwinding material, adjusting process parameters, and replacing the main compaction roller pair, fiber-reinforced metal laminates ranging from flat sheets to various complex interface shapes can be produced, meeting the needs of different fields such as aerospace, high-end electronics, and automotive lightweighting. Through an integrated continuous production line design, combined with precise temperature and pressure control and innovative embossing technology, efficient, high-quality, highly consistent, and customizable production of fiber-reinforced metal laminates is achieved. It is particularly suitable for the manufacture of precision, ultra-thin components, possessing significant industrial application value and market prospects. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0022] Figure 2 This is an overall structural layout diagram of the present invention;

[0023] Figure 3 This is a schematic diagram of the lamination and compaction system in this invention;

[0024] Figure 4 This is a schematic diagram of the first structure of the main compaction roller for embossing in this invention;

[0025] Figure 5 This is a schematic diagram of the second structure of the main compaction roller for embossing in this invention;

[0026] Figure 6 This is a schematic diagram of the third structure of the main compaction roller for embossing in this invention.

[0027] Figure label:

[0028] 1. Frame; 2. Unwinding system; 21. Upper unwinding roll; 22. Lower unwinding roll; 3. Preheating system; 31. Preheating roll system; 32. Preheating source; 4. Lamination and compaction system; 41. Precompacting roll system; 42. Main compaction roll pair; 5. Cooling and setting system; 51. Water-cooled roll system; 6. Rewinding system; 61. Upper rewinding roll; 62. Lower rewinding roll. Detailed Implementation

[0029] The present invention will now be further described with reference to the accompanying drawings. The following embodiments are only used to illustrate the structure of the present invention more clearly.

[0030] like Figure 1 and Figure 2 As shown, a continuous forming equipment for carbon fiber prepreg-stainless steel ultrathin strip fiber metal laminate includes a frame 1, on which an unwinding system 2, a preheating system 3, a lamination and compaction system 4, a cooling and shaping system 5, and a winding system 6 are arranged sequentially along the material travel direction.

[0031] The unwinding system 2 includes an upper unwinding roller 21 and a lower unwinding roller 22. The roller gap between the upper unwinding roller 21 and the lower unwinding roller 22 serves as the material inlet. The upper unwinding roller 21 and the lower unwinding roller 22 enable the feeding of stainless steel ultra-thin strips or carbon fiber prepreg. Each of the upper unwinding roller 21 and the lower unwinding roller 22 includes at least one. Figure 1 With one upper unwinding roller 21 and one lower unwinding roller 22, a fiber metal layer consisting of one layer of carbon fiber prepreg and one layer of stainless steel ultrathin strip can be produced. When multiple layers (such as sandwich structure or multi-layer alternating structure) are required, multiple sets of unwinding rollers can be arranged in parallel along the material travel direction. The position and number of unwinding rollers for carbon fiber prepreg and stainless steel ultrathin strip are allocated according to the structural design. Finally, all layers are gathered and stacked before entering the preheating system 3.

[0032] The upper unwinding roller 21 and the lower unwinding roller 22 of the unwinding system 2 are used to carry carbon fiber prepreg rolls and stainless steel ultrathin strip rolls, respectively. Under the control of the drive device, the unwinding rollers unwind the raw materials with constant tension or speed and feed them into the subsequent work station precisely and synchronously.

[0033] The preheating system 3 includes a preheating roller system 31 and preheating sources 32. Preheating sources 32 are symmetrically arranged vertically at the gaps in the preheating roller system 31. The preheating sources 32 do not contact the material; the material forms a laminated material after passing through the preheating system. The preheating source 32 can be an infrared heater or a hot air nozzle, which softens the resin in the prepreg, making it viscous and fluid, creating conditions for bonding with the metal strip. It also reduces the yield strength of the ultra-thin stainless steel strip, making it easier to plastically deform during subsequent pressing, reducing springback and internal stress. This allows the material to bond faster and better when entering the lamination and compaction system 4, reducing defects.

[0034] like Figure 3 As shown, the lamination and compaction system 4 is sequentially arranged with a pre-compacting roller system 41 and a main compacting roller pair 42 along the material travel direction. The pre-compacting roller system 41 uses smooth-surfaced heated pressure rollers, responsible for the initial compaction and guidance of the preheated laminated material. The main compacting roller pair 42 consists of two upper and lower heated pressure rollers. The roller surfaces of the upper and lower heated pressure rollers of the main compacting roller pair 42 are provided with paired concave and convex embossing patterns to complete the pressing of the laminated material and form a high-temperature laminated material. In this system, under the combined action of heat and force, different layers of materials are firmly bonded into a whole and pressed into a preset structural shape, which is the core station of the entire equipment.

[0035] The main compaction roller pair 42 is a detachable structure, and the embossing shape on the roller surface of the main compaction roller pair 42 can be set according to requirements, such as... Figure 4 The embossing shape on the 42 roller surface of the main compaction roller shown is a corrugated shape used to form alternating peaks and troughs, such as... Figure 5 The main compaction roller shown has a trapezoidal shape with shaped trapezoidal reinforcing ribs on its 42 roller surface, as shown in the figure. Figure 6 The main compaction rollers shown have 42 roller surfaces with triangular shapes for forming triangular reinforcing ribs. By pre-setting embossing on the rollers, corrugated, trapezoidal, and triangular reinforcing rib structures are directly formed on the laminate, achieving integrated manufacturing of structure and function.

[0036] The main compaction roller pair 42 integrates a heating system that controls the roller surface temperature within the range of 300℃-450℃. Both the pre-compaction roller system 41 and the main compaction roller pair 42 are equipped with a pressurization system, providing a linear pressure of 20t-50t. The temperature and pressure of the main compaction roller pair 42 are higher than those of the pre-compaction roller system 41. Under extremely high linear pressure and precise temperature, a strong mechanical interlock and interfacial bond are formed between the resin and the metal.

[0037] The cooling and shaping system 5 includes a water-cooled roller system 51, which consists of multiple rollers internally equipped with a cooling medium. This system allows for the controlled and uniform cooling of the high-temperature laminated material, completing the shaping process. The laminated material is at a very high temperature and in a plastic state. This system, through multiple water-cooled rollers contacting the material surface, rapidly and uniformly removes heat during the material's movement, causing the thermoplastic resin to re-solidify and "freeze" the formed shape. Furthermore, it minimizes warping, twisting, and internal stress caused by temperature differences, ensuring dimensional stability of the product and facilitating winding.

[0038] The winding system 6 includes an upper winding roller 61 and a lower winding roller 62. The roller gap between the upper winding roller 61 and the lower winding roller 62 serves as the profile output port. The upper winding roller 61 and the lower winding roller 62 apply appropriate tension to the final product coming out of the cooling and shaping system 5 and wind it neatly and tightly into a large coil, achieving continuous production and facilitating storage, transportation, and subsequent cutting processing.

[0039] The unwinding system 2, preheating system 3, lamination and compaction system 4, cooling and shaping system 5, and winding system 6 all have their upper and lower parts aligned on the same center line. This design ensures that the material is consistently and smoothly conveyed along a straight line during its journey, maximizing the protection of the integrity of the fibers and metal strip. It also guarantees that pressure is applied vertically and evenly across the entire width of the material, preventing uneven shear stress that could lead to poor bonding, uneven thickness, or uneven resin distribution in the laminate.

[0040] The production process of this invention is as follows: (1) Unwinding and feeding: The upper and lower unwinding rollers start synchronously under the command of the control system, respectively unfolding the carbon fiber prepreg and the stainless steel ultrathin strip precisely and smoothly. The two are aligned at the meeting point and enter the next stage together with constant tension. (2) Online preheating: The merged multilayer material enters the preheating zone. The non-contact preheating sources set up symmetrically on the upper and lower sides simultaneously radiate or convect heat the material. This stage is the "activation" stage and no adhesion is generated. The prepreg resin softens and the stainless steel plasticity is enhanced, preparing for lamination. (3) Lamination and compaction: This step is divided into two stages and is the core of the whole process. First, the preheated material passes through the pre-compacting roller system 41 to discharge the interlayer gas, so that each layer is initially bonded and precisely guided to the main compaction zone; the material enters the pressing zone of the main compacting roller pair 42. Under high temperature and high pressure, the roller pair uses the embossed texture on its roller surface to forcefully squeeze the material. At this moment, the resin flow and curing, the interface firm bonding and macro embossing are completed in one step. (4) Cooling and molding: The high-temperature laminate with embossed structure immediately enters the water-cooled roller system 51. Through contact with the surface of the water-cooled rollers, the heat is quickly and evenly removed. This stage is the "shaping" process. The resin matrix re-solidifies, permanently fixing the shape and structure after molding and minimizing warping and internal stress. (5) Winding: The fully cooled and shaped fiber-metal laminate with stable dimensions is finally sent to the winding system 6. The upper and lower winding rollers wind it into a large roll under constant tension, producing the final product form - a large roll of structurally and functionally integrated fiber-metal laminate, which is convenient for subsequent storage, transportation and processing. This device realizes the material from roll to roll without interruption. All key processes are completed online sequentially on a production line, which greatly improves production efficiency, product consistency and automation. It is the key to realizing the large-scale industrial production of this type of advanced composite material.

[0041] In this invention, the unwinding system 2, the preheating system 3, the lamination and compaction system 4, the cooling and shaping system 5, and the winding system 6 each consist of upper and lower parts. The preheating system 3, the lamination and compaction system 4, and the cooling and shaping system 5 are each composed of multiple sets of rollers arranged in pairs. The two winding rollers of the winding system 6 are also arranged opposite to each other. This structure is a common existing technology in the processing of steel strips, etc., so it is not described in detail.

[0042] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A carbon fiber prepreg-stainless steel ultrathin tape fiber metal laminate continuous forming equipment, comprising a rack, characterized in that: The frame is equipped with an unwinding system, a preheating system, a laminating and compacting system, a cooling and shaping system, and a winding system, arranged sequentially along the material travel direction. The unwinding system includes an upper unwinding roller and a lower unwinding roller. The roller gap between the upper unwinding roller and the lower unwinding roller is the material inlet. The upper unwinding roller and the lower unwinding roller realize the feeding of stainless steel ultra-thin strip or carbon fiber prepreg. The preheating system includes a preheating roller system and a preheating source. The preheating source is symmetrically arranged above and below at the gap position of the preheating roller system. The preheating source does not contact the material. After the material passes through the preheating system, it forms a laminated material. The lamination and compaction system is arranged sequentially along the material travel direction with a pre-compacting roller system and a main compacting roller pair. The pre-compacting roller system consists of multiple sets of smooth-surfaced heated and pressurized rollers, responsible for the initial compaction and guidance of the preheated laminated material. The main compacting roller pair consists of upper and lower heated and pressurized rollers, with paired embossed textures on the roller surfaces to shape the laminated material and form a high-temperature laminated material. The main compacting roller pair integrates a heating system that controls the roller surface temperature within the range of 300℃-450℃. Both the pre-compacting roller system and the main compacting roller pair are equipped with pressurization systems that provide a linear pressure of 20t-50t. The temperature and pressure of the upper and lower rollers in the main compacting roller pair are higher than those of the rollers in the pre-compacting roller system. The cooling and shaping system includes a water-cooled roller system, which consists of multiple rollers with internal cooling media, enabling the high-temperature laminated material to be cooled in a controllable and uniform manner to complete the shaping process. The winding system includes an upper winding roller and a lower winding roller, and the roller gap between the upper winding roller and the lower winding roller is the profile output port; The five systems—unwinding system, preheating system, lamination and compaction system, cooling and shaping system, and winding system—have their upper and lower parts forming the center line of the roll gap on the same center line.

2. The continuous forming equipment for carbon fiber prepreg-stainless steel ultrathin fiber metal laminate according to claim 1, characterized in that: The upper unwinding roller and the lower unwinding roller each include at least one.

3. The continuous forming equipment of carbon fiber prepreg-stainless steel ultra-thin tape fiber metal laminates according to claim 1, characterized in that: The preheating source is an infrared heater or a hot air nozzle.

4. The continuous forming equipment of carbon fiber prepreg-stainless steel ultra-thin tape fiber metal laminates according to claim 1, characterized in that: The main compaction roller pair is a detachable structure, and the embossing shape on the roller surface of the main compaction roller pair can be set as required.

5. The continuous forming equipment of carbon fiber prepreg-stainless steel ultrathin tape fiber metal laminates according to claim 4, characterized in that: The embossing shapes on the main compaction roller surface include corrugated shapes for forming alternating peaks and troughs, trapezoidal shapes for forming trapezoidal reinforcing ribs, and triangular shapes for forming triangular reinforcing ribs.

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