Method for manufacturing composite board through laser cutting and hot-pressing connection

Abstract

The invention discloses a method for manufacturing a composite board through laser cutting and hot-pressing connection. The method comprises the following steps that S1, materials of the composite board are prepared; s2, laser cutting treatment is carried out, and a first cut sheet of a second fiber reinforced plastic sheet and a second cut sheet of a second metal sheet are obtained; s3, the first cutting sheet and the second cutting sheet are placed in holes of the second metal sheet and the second fiber reinforced plastic sheet which are adjacent to each other correspondingly; and S4, alternately stacking the second metal sheets and the second fiber reinforced plastic sheets treated in the step S3, fixing the second metal sheets and the second fiber reinforced plastic sheets with the first metal sheets and the first fiber reinforced plastic sheets, and then performing hot-pressing connection. The composite material has the advantages that the composite material can penetrate into a plate to create more contact interfaces for two materials, and under the action of hot pressing, dissimilar materials are mutually diffused and subjected to chemical reaction, so that a firmer and more stable combination is formed, and the overall performance of the composite material is improved.

Description

Technical Field

[0001] The invention relates to the technical field of metal and fiber reinforced plastic dissimilar material connection, and in particular to a method for manufacturing a composite plate by utilizing laser cutting and hot pressing connection. Background Art

[0002] Driven by the national green development strategy, with the growing demand for lightweight, high-strength and corrosion-resistant structures, metals and fiber-reinforced plastics, as two major types of high-performance materials, have shown great application potential in aerospace, automobile manufacturing, new energy and other fields due to their unique physical and chemical properties. However, due to the huge difference in performance between the two, the connection between them still faces many challenges. Therefore, in-depth research on effective connection methods of dissimilar materials such as metals and fiber-reinforced plastics is of great significance to promote the development of multi-material heterogeneous structures.

[0003] The methods currently used for metals and fiber-reinforced plastics mainly include mechanical connection (bolt connection, riveting), welding (resistance welding, laser welding, ultrasonic welding, etc.) and bonding. Among them, the mechanical connection method cannot avoid the problem of material damage and is not conducive to the lightweight structure; the welding method often requires the material to be heated to a molten or semi-molten state, which may cause thermal degradation of the resin matrix in the composite material or degradation of the carbon fiber performance, and the welding connection area is limited. In addition, if the material surface is not fully pretreated before welding, the joint performance will be difficult to meet the actual application requirements, thereby pushing up the manufacturing cost; the adhesive used for bonding is prone to aging as the use time increases, and there is a risk of condensation and damage in the adhesive layer.

[0004] Compared with the above methods, the hot pressing connection technology not only promotes the softening and plastic deformation of the material by heating and pressurizing, but also significantly enhances the gravitational force between atoms at the interface, thereby ensuring close contact and firm bonding between the materials. In addition, a major advantage of the hot pressing connection technology is that it has a wide connection area, and different pressure heads can be flexibly applied to achieve comprehensive connection of the entire sheet, thereby improving the efficiency and stability of the connection. In the prior art field, patent CN116749607A discloses a metal-nonmetal connection method and a connection assembly, which places a layer of film with polar surface characteristics between the metal and the nonmetal to be connected, and then uses a hot pressing connection strategy of heating the metal side and pressurizing the nonmetal side to achieve an efficient and stable sealed connection between the two. However, the limitation of this method is that its connection effect is mainly limited to the surface layer of the sheet, and has limited effect on significantly improving the overall mechanical properties. At the same time, the selection of the intermediate layer film needs to take into account the good affinity for the heterogeneous materials on both sides, which constitutes certain challenges and limitations in practical applications, affecting the wide applicability of the technology. Therefore, it is urgent to provide a method for manufacturing metal and fiber reinforced plastic composite sheets using laser cutting and hot pressing connection. Summary of the invention

[0005] Purpose of the Invention In order to solve the current problem of hot pressing connection between metal and non-metal, the present invention provides a method for manufacturing composite plates using laser cutting and hot pressing connection, which can enable dissimilar materials to not only provide multi-area connections on the surface of the plate, but also penetrate deep into the plate to create more contact interfaces for the two materials; at the same time, under the action of hot pressing, the dissimilar materials diffuse with each other and react chemically, thereby forming a more solid and stable combination, greatly improving the overall performance of the composite material.

[0006] To achieve the above object, the present invention provides the following technical solutions: The object of the present invention is to provide a method for manufacturing a composite plate by laser cutting and hot pressing, comprising the following steps: S1: preparing materials for a composite sheet, wherein the materials for the composite sheet include a first metal sheet, an intermediate layer and a first fiber reinforced plastic sheet, wherein the intermediate layer includes a plurality of second metal sheets and second fiber reinforced plastic sheets; S2: performing laser cutting processing on the adjacent second metal sheet and the second fiber reinforced plastic sheet using a laser beam, and cutting corresponding identical holes in the adjacent second metal sheet and the second fiber reinforced plastic sheet, and obtaining a first cut sheet of the second fiber reinforced plastic sheet and a second cut sheet of the second metal sheet; S3: placing the first cut sheet into the hole of the adjacent second metal sheet, and placing the second cut sheet into the hole of the adjacent second fiber reinforced plastic sheet; S4: Alternately stack the plurality of second metal sheets and second fiber reinforced plastic sheets processed in step S3 to form an intermediate layer to be pressurized, and the second metal sheets and second fiber reinforced plastic sheets on both sides of the intermediate layer to be pressurized are respectively bonded to the first fiber reinforced plastic sheet and the first metal sheet, and then the second metal sheet, the second fiber reinforced plastic sheet, the first metal sheet and the first fiber reinforced plastic sheet are fixed together by clamps, and then hot-pressed.

[0007] As a further description of the above scheme, in step S1, the length, width and thickness of the first metal sheet, the second metal sheet, the first fiber reinforced plastic sheet and the second fiber reinforced plastic sheet are all the same, and the thickness of the first metal sheet is 0.2-0.5 mm; the first metal sheet and the second metal sheet are made of the same material, and the first metal sheet is made of aluminum alloy, magnesium alloy or titanium alloy; the first fiber reinforced plastic sheet and the second fiber reinforced plastic sheet are made of the same material, and the first fiber reinforced plastic sheet includes fiber and plastic, and the fiber is made of carbon fiber or glass fiber; the plastic is made of thermoplastic plastic.

[0008] As a further description of the above scheme, in step S2, the laser power used in the laser cutting process of the second metal sheet is 800-1500W; the cutting speed of the laser cutting process of the second metal sheet is 150-200mm / s, and the auxiliary gas pressure of the laser cutting process of the metal material is 1MPa; The laser power of the laser cutting process of the second fiber reinforced plastic sheet is 800-1200W, the cutting speed of the laser cutting process of the second fiber reinforced plastic sheet is 15-25mm / s, and the auxiliary gas pressure of the laser cutting process of the second fiber reinforced plastic sheet is 0.5-0.7MPa.

[0009] As a further description of the above scheme, in step S2, the second metal sheet and the second fiber reinforced plastic sheet are laser cut, and the path of the laser cutting process is through circular lines arrayed simultaneously in the X direction and the Y direction, and the diameter of the obtained circular holes is 3-4 times the thickness of the sheet, and the center distance between adjacent circular holes is 2-2.5 times the diameter of the circular holes, and the number of arrays is an even number; the second metal sheet selects circles in odd rows and odd columns for cutting, and the second fiber reinforced plastic sheet selects circles in even rows and even columns for cutting.

[0010] As a further description of the above scheme, in step S2, the distance between the edge of the second metal sheet and the hole processed by laser cutting of the adjacent second metal sheet is more than 4 times the diameter of the hole; the distance between the edge of the second fiber reinforced plastic sheet and the hole processed by laser cutting of the second fiber reinforced plastic sheet is more than 4 times the circular diameter.

[0011] As a further description of the above scheme, in step S4, before hot pressing connection, the second metal sheet, the second fiber reinforced plastic sheet, the first metal sheet and the first fiber reinforced plastic sheet are laid in the following order: the first fiber reinforced plastic sheet is placed on the bottom layer, and then the second metal sheet and the second fiber reinforced plastic sheet processed in step S3 are laid alternately from bottom to top, and the first metal sheet is placed on the top layer; the composite sheet formed by the first metal sheet, the middle layer and the first fiber reinforced plastic sheet has an overall thickness of 0.8-8mm.

[0012] As a further description of the above scheme, in step S4, the hot pressing temperature of the hot pressing connection is 280-450°C, the hot pressing pressure of the hot pressing connection is 4-15Mpa, and the insulation time of the hot pressing connection is 5-45min.

[0013] As a further description of the above scheme, in step S4, before hot pressing and connection, they need to be sealed and preserved, and after cleaning the dust and impurities on the surfaces of the first metal sheet, the second metal sheet, the second fiber reinforced plastic sheet and the first fiber reinforced plastic sheet, they are placed flat between the upper pressure head and the lower pressure head, and the upper pressure head and the lower pressure head are arranged parallel to each other, and then clamped and fixed with a clamp.

[0014] The beneficial effects of the present invention include the following: 1. Laser cutting will burn a certain amount of material due to its own process characteristics. In order to reduce the difference in material burning, different parameter ranges are set to unify the sizes of the two types of cut sheets and ensure the uniformity of the structure. In addition, the diameter of the circular sheet left after cutting is smaller than the hole diameter. After filling the other material, it will not bring additional stress, and reserve space for the expansion of the material during the hot pressing process.

[0015] 2. In the process of precisely controlling the core parameters such as the power output and scanning rate of laser cutting and the hot pressing temperature and pressure in the hot pressing connection process, highly accurate filling of the hole area of ​​the cut sheet is achieved. This synergistic optimization strategy of laser and hot pressing technology not only effectively curbs the generation of hole defects inside the composite sheet, but also greatly enhances the overall quality and performance of the sheet.

[0016] 3. When using the traditional welding mode, dissimilar materials are only connected in a limited area of ​​the contact surface. This method not only provides multi-area connections on the surface of the plate (horizontally), but also penetrates deep into the plate (i.e. vertically), creating more contact interfaces for the two materials. Under the action of hot pressing, dissimilar materials diffuse with each other and react chemically, thus forming a more solid and stable combination, greatly improving the overall performance of the composite material.

[0017] 4. In terms of spatial structure, the two materials are interwoven like two nets. This design can effectively disperse stress to the entire plate area when bearing load, thereby significantly improving the load-bearing capacity and fatigue resistance of the composite plate.

[0018] 5. Although laser cutting technology has thickness limitations when processing single-layer thin plates, with the support of the heating and pressurizing characteristics of the hot pressing connection method, the thickness range of the composite plate can be greatly expanded by alternately stacking and compounding multiple layers of plate materials, so that it can flexibly adapt to various complex operating conditions and performance requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the laser cutting processing area of ​​the present invention. Figure 2 Schematic diagram of the sequential laying of materials before hot pressing connection of the present invention, wherein the upper figure is a schematic diagram of the filling of the cut sheets of the second metal sheet and the second fiber reinforced plastic sheet of the middle layer, the lower left figure is a schematic diagram of the composite sheet after laying, and the lower right figure is a cross-sectional view of the composite sheet after laying in the lower left figure; Figure 3 It is a schematic diagram of the hot pressing connection of the present invention.

[0020] Explanation of the accompanying figure numbers: 1-second metal sheet; 2-laser beam; 3-second fiber reinforced plastic sheet, 4-first cutting sheet; 5-first metal sheet; 6-first fiber reinforced plastic sheet; 7-upper pressure head; 8-clamp; 9-lower pressure head; 10-second cutting sheet. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. On the contrary, the present invention covers any substitutions, modifications, equivalent methods and schemes made on the essence and scope of the present invention as defined by the claims. Further, in order to enable the public to have a better understanding of the present invention, some specific details are described in detail in the detailed description of the present invention below, and those skilled in the art can fully understand the present invention without the description of these details.

[0022] In this embodiment, the equipment used for laser surface treatment is a fiber laser (M7 500-1000W, JPT laser), which can accurately cut the experimental material by adjusting parameters such as laser power, cutting speed, laser frequency, etc., combined with the path drawn by the control software. The hot press can manufacture metal and fiber reinforced plastic composite panels by adjusting parameters such as hot pressing temperature, hot pressing pressure and holding time.

[0023] A method for manufacturing a metal and fiber reinforced plastic composite plate by laser cutting and hot pressing, comprising the following steps: S1: preparing materials for a composite sheet, wherein the materials for the composite sheet include a first metal sheet 5, an intermediate layer and a first fiber reinforced plastic sheet 6, wherein the intermediate layer includes a plurality of second metal sheets 1 and second fiber reinforced plastic sheets 3; S2: The adjacent second metal sheet 1 and the second fiber reinforced plastic sheet 3 are laser cut by a laser beam 2, and the adjacent second metal sheet 1 and the second fiber reinforced plastic sheet 3 are both cut with a corresponding number of identical holes, and a first cut sheet 10 of the second fiber reinforced plastic sheet 3 and a second cut sheet 4 of the second metal sheet 1 are obtained; S3: placing the first cut sheet 10 into the hole of the adjacent second metal sheet 1, and placing the second cut sheet 4 into the hole of the adjacent second fiber reinforced plastic sheet 3; S4: Alternately stack the plurality of second metal sheets 1 and second fiber reinforced plastic sheets 3 processed in step S3 to form an intermediate layer to be pressurized, and the second metal sheets 1 and second fiber reinforced plastic sheets 3 on both sides of the intermediate layer to be pressurized are respectively bonded to the first fiber reinforced plastic sheet 6 and the first metal sheet 5, and then the second metal sheet 1, the second fiber reinforced plastic sheet 3, the first metal sheet 5 and the first fiber reinforced plastic sheet 6 are fixed together by a clamp 8, and then hot-pressed.

[0024] In order to reduce the difference in material burning, the laser cutting process of this design sets different parameter ranges to unify the sizes of the two types of cut sheets and ensure the uniformity of the structure. In addition, the diameter of the circular sheet left after cutting is smaller than the aperture, so that after filling the other material, no additional stress will be brought, and space will be reserved for the expansion of the material during the hot pressing process; in addition, when the traditional welding mode is adopted, the dissimilar materials are only connected in a limited area of ​​the contact surface. This method not only provides multi-area connection within the surface of the plate (horizontal direction), but also penetrates into the interior of the plate (i.e. vertical direction), creating more contact interfaces for the two materials. Under the action of hot pressing, the dissimilar materials diffuse with each other and react chemically, thereby forming a more solid and stable combination, which greatly improves the overall performance of the composite material; at the same time, in terms of spatial structure, the two materials are like two nets intertwined with each other. This design can effectively disperse the stress to the entire plate area when bearing load, thereby significantly improving the load-bearing capacity and fatigue resistance of the composite plate; secondly, although there is a thickness limitation when processing single-layer thin plates using laser cutting technology, with the support of the heating and pressurization characteristics of the hot pressing connection method, multiple layers of plates can be alternately stacked and compounded, which can greatly expand the thickness range of the composite plate, allowing it to flexibly adapt to various complex operating conditions and performance requirements.

[0025] In step S1 of the present invention, the length, width and thickness of the first metal sheet 5, the second metal sheet 1, the first fiber reinforced plastic sheet 6 and the second fiber reinforced plastic sheet 3 are the same, and the thickness of the first metal sheet 5 is 0.2-0.5 mm; the first metal sheet 5 and the second metal sheet 1 are made of the same material, and the first metal sheet 5 is made of aluminum alloy, magnesium alloy or titanium alloy; the first fiber reinforced plastic sheet 6 and the second fiber reinforced plastic sheet 3 are made of the same material, and the first fiber reinforced plastic sheet 6 includes fiber and plastic, wherein the fiber is made of carbon fiber or glass fiber; wherein the plastic is made of thermoplastic plastic.

[0026] In step S2 of the present invention, the laser power used in the laser cutting process of the second metal sheet is 800-1500W; the cutting speed of the laser cutting process of the second metal sheet is 150-200mm / s, and the auxiliary gas pressure of the laser cutting process of the metal material is 1MPa; The laser power of the second fiber reinforced plastic sheet laser cutting process is 800-1200W, the cutting speed of the second fiber reinforced plastic sheet laser cutting process is 15-25mm / s, and the auxiliary gas pressure of the second fiber reinforced plastic sheet laser cutting process is 0.5-0.7MPa; processing under the above parameters can not only improve the cutting efficiency, but also avoid excessive burning of materials due to overheating, unify the sizes of the two types of cut sheets, and achieve highly accurate filling of the hole areas of the cut sheets. This synergistic optimization strategy of laser and hot pressing technology not only effectively curbs the generation of hole defects inside the composite sheet, but also greatly enhances the overall quality and performance of the sheet, providing a good foundation for subsequent processing steps.

[0027] In step S2 of the present invention, the second metal sheet and the second fiber reinforced plastic sheet are laser cut, and the path of the laser cutting process is through circular lines arrayed simultaneously in the X direction and the Y direction, and the diameter of the obtained circular holes is 3-4 times the thickness of the sheet, and the center distance between adjacent circular holes is 2-2.5 times the diameter of the circular holes, and the number of arrays is an even number; the second metal sheet selects circles in odd rows and odd columns for cutting, and the second fiber reinforced plastic sheet selects circles in even rows and even columns for cutting, thereby ensuring that the number of first cut sheets and second cut sheets is equal.

[0028] In step S2 of the present invention, the distance between the edge of the second metal sheet and the adjacent hole laser cut in the second metal sheet is more than 4 times the hole diameter; the distance between the edge of the second fiber reinforced plastic sheet and the hole laser cut in the second fiber reinforced plastic sheet is more than 4 times the circular diameter.

[0029] In step S4 of the present invention, before hot pressing connection, the second metal sheet 1, the second fiber reinforced plastic sheet 3, the first metal sheet 5 and the first fiber reinforced plastic sheet 6 are laid in the following order: the first fiber reinforced plastic sheet 6 is placed on the bottom layer, and then the second metal sheet 1 and the second fiber reinforced plastic sheet 3 processed in step S3 are laid alternately from bottom to top, and the first metal sheet 1 is placed on the top layer; the first metal sheet 5, the middle layer and the first fiber reinforced plastic sheet 6 form a composite sheet, wherein the overall thickness of the composite sheet is 0.8-8 mm.

[0030] In step S4 of the present invention, the hot pressing temperature of the hot pressing connection is 280-450°C, the hot pressing pressure of the hot pressing connection is 4-15Mpa, and the insulation time of the hot pressing connection is 5-45min, ensuring that the materials are fully heated during the hot pressing process, thereby promoting close bonding between the materials.

[0031] In step S4 of the present invention, before hot pressing and connection, they need to be sealed and stored, and after cleaning the dust and impurities on the surfaces of the first metal sheet 5, the second metal sheet 1, the second fiber reinforced plastic sheet 3 and the first fiber reinforced plastic sheet 6, they are placed flat between the upper pressure head 7 and the lower pressure head 9, and the upper pressure head 7 and the lower pressure head 9 are arranged parallel to each other, and then clamped and fixed with a clamp 8 to ensure that the surface of the sample is evenly pressurized when pressurizing. Example

[0032] In this example, laser cutting and hot pressing were used to successfully prepare a composite sheet composed of 6061 aluminum alloy and reinforced PEEK with a carbon fiber content of 30%. The raw materials used were all thin sheets with a size of 80mm×80mm×0.3mm. Before hot pressing, the two types of thin sheets were arranged in order: the uncut aluminum alloy sheet was at the bottom, the uncut carbon fiber reinforced PEEK sheet was at the top, and the laser-cut thin sheets were alternately stacked in the middle.

[0033] Step 1: Draw the laser cutting path. First, draw a circular line with a diameter of 1 mm. Then, based on this, array 34 lines (including the initial pattern) in the X and Y directions at the same time. The array length is 2 mm to obtain the cutting path.

[0034] Step 2: Set the laser cutting parameters. The process parameters for laser cutting of metal materials are: laser power 800-1500W, cutting speed 150-200mm / s, auxiliary gas pressure 1MPa. The process parameters for laser cutting of fiber reinforced plastics are: laser power 800-1200W, cutting speed 15-25mm / s, auxiliary gas pressure 0.5-0.7MPa. When cutting, ensure that the distance between the boundary of the laser cutting area and the edge of the thin plate is 5.5mm.

[0035] Step 3: Lay the pre-pressed plates, put the untreated 0.3 mm 6061 aluminum alloy sheet on the bottom layer, then lay the cut carbon fiber reinforced PEEK sheet, and fill the gaps with the 6061 aluminum alloy round sheets, then lay the cut 6061 aluminum alloy sheet, fill the gaps with the carbon fiber reinforced PEEK round sheets, alternately lay them four times, and place the untreated 0.3 mm carbon fiber reinforced PEEK sheet on the top. The theoretical composite plate thickness is 3 mm.

[0036] Step 4: Tighten the clamps around firmly to ensure that the laid sheet is fixed. Then, start the heating program, and gradually heat the mold from room temperature to 280-450℃ at a uniform rate of 15℃ per minute, and keep it constant after reaching this temperature. During this period, apply a pressure of 4-15Mpa and keep warm for 20 minutes. After the hot pressing connection is completed, take the natural cooling method to let the sheet cool down slowly, so as to effectively prevent the additional stress problems that may be generated during the rapid cooling process.

[0037] The above is only an embodiment of the present application and does not constitute any form of limitation to the present application. Although the present application is disclosed as above with a preferred embodiment, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for manufacturing a composite sheet by laser cutting and hot pressing, characterized in that: The following steps are involved: S1: preparing materials for a composite sheet, wherein the materials for the composite sheet include a first metal sheet (5), an intermediate layer and a first fiber-reinforced plastic sheet (6), wherein the intermediate layer includes a plurality of second metal sheets (1) and second fiber-reinforced plastic sheets (3); S2: performing laser cutting processing on the adjacent second metal sheet (1) and the second fiber reinforced plastic sheet (3) using a laser beam (2), and cutting the adjacent second metal sheet (1) and the second fiber reinforced plastic sheet (3) into a corresponding number of identical holes, thereby obtaining a first cut sheet (10) of the second fiber reinforced plastic sheet (3) and a second cut sheet (4) of the second metal sheet (1); S3: placing the first cut sheet (10) into the hole of the adjacent second metal sheet (1), and placing the second cut sheet (4) into the hole of the adjacent second fiber reinforced plastic sheet (3); S4: The plurality of second metal sheets (1) and second fiber reinforced plastic sheets (3) processed in step S3 are alternately stacked to form an intermediate layer to be pressurized, and the second metal sheets (1) and second fiber reinforced plastic sheets (3) on both sides of the intermediate layer to be pressurized are respectively bonded to the first fiber reinforced plastic sheet (6) and the first metal sheet (5), and then the second metal sheet (1), the second fiber reinforced plastic sheet (3), the first metal sheet (5) and the first fiber reinforced plastic sheet (6) are fixed together by a clamp (8), and then hot-pressed.

2. The method for manufacturing metal and fiber reinforced plastic composite sheet by laser cutting and hot pressing connection according to claim 1, characterized in that: In the step S1, the length, width and thickness of the first metal sheet (5), the second metal sheet (1), the first fiber-reinforced plastic sheet (6) and the second fiber-reinforced plastic sheet (3) are all the same, and the thickness of the first metal sheet (5) is 0.2-0.5 mm; the first metal sheet (5) and the second metal sheet (1) are made of the same material, and the first metal sheet (5) is made of aluminum alloy, magnesium alloy or titanium alloy; the first fiber-reinforced plastic sheet (6) and the second fiber-reinforced plastic sheet (3) are made of the same material, and the first fiber-reinforced plastic sheet (6) comprises fibers and plastics, the fibers are made of carbon fibers or glass fibers; and the plastics are made of thermoplastic plastics.

3. The method for manufacturing metal and fiber reinforced plastic composite sheet material by laser cutting and hot pressing connection according to claim 1, characterized in that: In the step S2, the laser power used in the laser cutting process of the second metal sheet is 800-1500W; the cutting speed of the laser cutting process of the second metal sheet is 150-200mm / s, and the auxiliary gas pressure of the laser cutting process of the metal material is 1MPa; The laser power of the laser cutting process of the second fiber reinforced plastic sheet is 800-1200W, the cutting speed of the laser cutting process of the second fiber reinforced plastic sheet is 15-25mm / s, and the auxiliary gas pressure of the laser cutting process of the second fiber reinforced plastic sheet is 0.5-0.7MPa.

4. The method for manufacturing metal and fiber reinforced plastic composite sheet material by laser cutting and hot pressing connection according to claim 3, characterized in that: In step S2, the second metal sheet (1) and the second fiber reinforced plastic sheet (3) are subjected to laser cutting processing, and the path of the laser cutting processing is through circular lines arrayed in the X direction and the Y direction at the same time, the diameter of the obtained circular holes is 3-4 times the thickness of the sheet, and the distance between the centers of adjacent circular holes is 2-2.5 times the diameter of the circular holes, and the number of arrays is an even number; the second metal sheet (1) selects circles in odd rows and odd columns for cutting, and the second fiber reinforced plastic sheet (3) selects circles in even rows and even columns for cutting.

5. The method for manufacturing metal and fiber reinforced plastic composite sheet material by laser cutting and hot pressing connection according to claim 4, characterized in that: In step S2, the distance between the edge of the second metal sheet and the adjacent hole cut by laser on the second metal sheet is more than 4 times the hole diameter; the distance between the edge of the second fiber reinforced plastic sheet and the hole cut by laser on the second fiber reinforced plastic sheet is more than 4 times the circular diameter.

6. The method for manufacturing metal and fiber reinforced plastic composite sheet material by laser cutting and hot pressing connection according to claim 1, characterized in that: In the step S4, before the hot pressing connection, the second metal sheet (1), the second fiber reinforced plastic sheet (3), the first metal sheet (5) and the first fiber reinforced plastic sheet (6) are laid in the following order: the first fiber reinforced plastic sheet (6) is laid on the bottom layer, and then the second metal sheet (1) and the second fiber reinforced plastic sheet (3) processed in the step S3 are laid alternately from bottom to top, and the first metal sheet (1) is laid on the top layer; the first metal sheet (5), the middle layer and the first fiber reinforced plastic sheet (6) form a composite sheet, and the overall thickness of the composite sheet is 0.8-8 mm.

7. The method for manufacturing metal and fiber reinforced plastic composite sheet material by laser cutting and hot pressing connection according to claim 6, characterized in that: In the step S4, the hot pressing temperature of the hot pressing connection is 280-450° C., the hot pressing pressure of the hot pressing connection is 4-15 MPa, and the heat preservation time of the hot pressing connection is 5-45 min.

8. The method for manufacturing metal and fiber reinforced plastic composite sheet material by laser cutting and hot pressing connection according to claim 7, characterized in that: In step S4, before hot pressing and connecting, they need to be sealed and stored, and dust and impurities on the surfaces of the first metal sheet (5), the second metal sheet (1), the second fiber reinforced plastic sheet (3) and the first fiber reinforced plastic sheet (6) need to be cleaned, and then they are placed flat between the upper pressing head (7) and the lower pressing head (9), and the upper pressing head (7) and the lower pressing head (9) are arranged parallel to each other, and then clamped and fixed with a clamp (8).

Images