Method for forming a car bumper beam based on a three-dimensional lattice composite material

Abstract

A kind of automobile crash beam forming method based on three-dimensional lattice composite material, comprising the following steps: S1, create three-dimensional lattice configuration extending to the edge of defined space in defined space size, and establish the database of each configuration and its corresponding performance parameters;S2, according to the performance requirement of crash beam, the crash beam is divided into multiple functional areas along the length direction, and according to the performance of different areas, respectively select the three-dimensional lattice configuration meeting the requirements from S1 and fill into each area, and fill each area space, form three-dimensional model of crash beam and output;S3, according to the three-dimensional model output in S2, the preform of three-dimensional lattice configuration required by each area is processed, the metal insert is placed in the preform, the skin is coated outside the preform, and the crash beam is co-cured.The formed automobile crash beam meets the requirements of lightweight, high stiffness, high energy absorption and multifunctional integration.

Description

Technical Field

[0001] This invention relates to a molding method for automotive parts, specifically a molding method for automotive anti-collision beams based on three-dimensional lattice composite materials, belonging to the field of automotive design and manufacturing technology. Background Technology

[0002] A car bumper beam is a beam installed inside the bumper, primarily used to absorb impact force during low-speed collisions and protect the radiator and longitudinal beams of the vehicle body. Currently, bumper beams are typically all-metal structures. However, for new energy vehicles, lightweighting is a crucial factor affecting their performance. Therefore, during structural design, composite materials are used for certain components, such as composite material bumper beams. Existing invention applications, such as CN202511059574.0 entitled "A Thermoplastic Composite Material Bumper Beam and Its Preparation Method," first fabricate a composite main beam and auxiliary supports, then weld the main beam to the auxiliary supports or connect them with connectors. Another invention application, CN202510710923.4 entitled "Bumper Beam and Its Manufacturing Method and Carrier," first forms a first beam structure, a second beam structure, and a third beam structure separately, then connects these three beam structures. Both methods involve first forming multiple independent components, then combining them into a whole through external connection structures or methods, which cannot effectively guarantee overall performance. Summary of the Invention

[0003] To address the aforementioned problems, this invention proposes a method for molding automotive anti-collision beams based on three-dimensional lattice composite materials. The molded automotive anti-collision beams simultaneously meet the requirements of lightweight, high stiffness, high energy absorption, and multifunctional integration.

[0004] The technical means adopted by this invention to solve the above problems is: a method for molding an automotive anti-collision beam based on a three-dimensional lattice composite material, comprising the following steps: S1, Create a three-dimensional lattice configuration within a limited space, extending to the edge of the limited space, and establish a database of each configuration and its corresponding performance parameters; S2, based on the performance requirements of the crash beam, divide the crash beam into multiple functional areas along its length, and select the required three-dimensional lattice configuration from S1 to fill each area according to the performance of each area, thus filling the space of each area, forming a three-dimensional model of the crash beam and outputting it. S3, based on the three-dimensional model output from S2, processes the preforms of the three-dimensional lattice configuration required for each region, places metal inserts inside the preforms, covers the preforms with skin, and solidifies them into a crash beam.

[0005] Furthermore, in S1, the defined space size is 10mm×10mm×10mm.

[0006] Furthermore, in S1, when creating a three-dimensional lattice configuration, the element size is first selected for each configuration.

[0007] Furthermore, in S1, the element dimensions include the outer diameter of the rod-shaped element and the thickness of the plate-shaped element.

[0008] Furthermore, in S1, the configurations include BCC, BCC-Z, FCC, Pyramid, and Octet structures. Among them, BCC is a body-centered cubic structure with the center of the cube connected to the eight corner points; BCC-Z is a Z-direction reinforced body-centered cubic structure with Z-direction vertical bars added on the basis of BCC; FCC is a face-centered cubic structure with the six face centers connected to the adjacent corner points; Pyramid is a pyramid-shaped structure with periodic arrangement of four-sided pyramidal units; and Octet is an octahedral tetrahedral structure composed of BCC and FCC.

[0009] Furthermore, in S1, the finite element analysis method is used to apply standard boundary conditions to each three-dimensional lattice configuration and calculate the corresponding performance parameters; or the actual processing and experimentation are used to obtain each performance parameter.

[0010] Furthermore, the standard boundary condition applied is as follows: the lower surface of the three-dimensional lattice configuration is fixed, and a load is applied to the upper surface to cause the three-dimensional lattice configuration to produce a strain of 1%.

[0011] Furthermore, the performance parameters obtained include: relative density, equivalent elastic modulus, equivalent yield strength, energy absorption characteristics, and applicable scenarios.

[0012] Furthermore, in S2, the anti-collision beam is divided into three functional areas and five parts along its length: one A1 area, two A2 areas, and two A3 areas.

[0013] Furthermore, Zone A1 is located in the middle of the crash beam and is the central energy absorption zone, accounting for 40% of the total length; Zone A3 is located at both ends of the crash beam and is the end installation zone, each accounting for 10% of the total length; Zone A2 is located between the central energy absorption zone and the end installation zone and is the transition zone, each accounting for 20% of the total length.

[0014] Furthermore, in S2, the specific method for filling each region with three-dimensional lattice configurations is as follows: First, based on the boundary dimensions (Xmin, Xmax, Ymin, Ymax, Zmin, Zmax) of each region and the side length of the selected configuration, the required number of configurations in each direction in the three-dimensional space of each region is calculated; then, the selected configurations are filled into the corresponding regions according to the calculated number to form a three-dimensional model.

[0015] Furthermore, in S2, a reserved position for placing metal inserts is designed on the three-dimensional model at the location where the anti-collision beam is used for connection.

[0016] Furthermore, in S3, the skin is made of carbon fiber / epoxy resin prepreg.

[0017] Furthermore, in S3, the metal insert has an anchoring structure on its outer surface, and adhesive is applied to the outside of the metal insert before it is placed in the reserved position; the number of skin layers on the outside of the metal insert and its adjacent positions is 1.5 to 2.5 times the number of skin layers in other positions, in order to enhance the connection strength at the metal insert.

[0018] Furthermore, in S3, during co-curing, the encapsulated whole is first sealed with a vacuum bag, and then the sealed whole is placed in a thermostatic precipitator. After vacuuming, it is heated, pressurized and kept warm for curing, and then cooled and depressurized after completion.

[0019] The beneficial effects of this invention are: This invention significantly improves efficiency in the design of automotive anti-collision beams and can obtain different dot matrix configurations in real time based on input parameters, achieving precise control of stiffness, energy absorption, and lightweight objectives. Furthermore, it can configure different microstructures according to performance requirements and achieve synergistic effects of multiple objectives such as lightweight, high stiffness, and high energy absorption. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the three-dimensional lattice configuration structure of Example 1; Figure 2 This is a schematic diagram of the front bumper beam structure of a car as shown in Example 1. Figure 3 This is a schematic diagram of the anti-collision beam area division in Example 1; Figure 4 This is a schematic diagram showing the filling of different regions with different configurations in Example 1; Figure 5 This is a 3D model of the anti-collision beam filled with a 3D dot matrix configuration, as shown in Example 1. Figure 6 This is a schematic diagram of the metal insert structure in Example 1; In the picture: 1. Metal insert. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings. The drawings are for illustrative purposes only, representing schematic diagrams rather than actual physical objects, and should not be construed as limiting the scope of this patent. To better illustrate the embodiments of the present invention, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings. Example 1

[0022] A method for molding automotive anti-collision beams based on three-dimensional lattice composite materials, such as Figure 2As shown, the anti-collision beam is a long, hollow, sandwich structure with an arc-shaped bend along its length to adapt to the front shape of the vehicle body. One side near each end has threaded holes for connection with other parts. The specific molding process is as follows: S1, Component Database S11, Component three-dimensional lattice configuration The unit dimensions, such as the outer diameter of the rod-shaped unit and the thickness of the plate-shaped unit, are limited to 2mm. The spatial size is limited to 10mm×10mm×10mm. Various three-dimensional lattice configurations with dimensions constrained within a standard cubic space are established through parametric modeling, such as... Figure 1 As shown, this embodiment includes a BCC body-centered cubic structure with the center of the cube connected to the eight corner points, a BCC-Z Z-direction reinforced body-centered cubic structure with Z-direction vertical rods added to the BCC, an FCC face-centered cubic structure with the six face centers connected to the adjacent corner points, a Pyramid pyramid structure with periodically arranged four-sided pyramidal units, and an Octet tetrahedral structure composed of BCC and FCC.

[0023] S12, Obtain the performance parameters for each 3D lattice configuration. Using the finite element method, standard boundary conditions were applied to each lattice element: the lower surface was fixed, and a compressive displacement of 0.1 mm was applied to the upper surface, corresponding to a 1% strain in the three-dimensional lattice configuration. Performance data such as relative density, equivalent elastic modulus, equivalent yield strength, and energy absorption characteristics were calculated. Based on these data, applicable scenarios were deduced. .

[0024] This completes the basic structure that can be used in the design process of the crash beam.

[0025] S2, Functional programmable design for the crash beam. S21, Regional Division Based on the load transfer path of a frontal collision with the crash beam, such as Figure 3 As shown, the crash beam is divided into three functional zones and five parts along its length: one A1 zone, two A2 zones, and two A3 zones. Zone A1, located in the middle of the crash beam, is the central energy-absorbing zone, accounting for 40% of the total length. This zone bears the initial impact in a frontal collision and must preferentially absorb collision energy, requiring a smooth crushing process and a long travel distance. Zones A3, located at both ends of the crash beam, are end mounting zones, each accounting for 10% of the total length, used for connecting to the energy-absorbing boxes. This zone must bear the bolt preload and the transmission of all collision loads, requiring the highest rigidity and connection strength. Zones A2, located between the central energy-absorbing zone and the end mounting zones, are transition zones, each accounting for 20% of the total length. This zone must smoothly transfer the remaining energy absorbed in the central zone to the ends while avoiding stress concentration.

[0026] S22, Configuration selection for each region. In the database within S1, select a configuration that matches the performance of each region, such as... Figure 4 As shown, the A1 region ultimately adopted a BCC configuration as the bending-dominant structure. Under axial compression, the members undergo progressive buckling, effectively absorbing impact energy and avoiding excessively high peak acceleration. The A2 region ultimately adopted a BCC-Z configuration, adding a Z-direction vertical member to the BCC structure, increasing stiffness by approximately two times while retaining some energy absorption capacity, making it suitable as a stiffness gradient transition layer. The A3 region ultimately adopted an Octet configuration, which has the highest requirements for stiffness and strength. Furthermore, since the A3 region has a structure for bolting to the energy-absorbing box, reserved positions for placing the metal insert 1 need to be designed at the corresponding locations.

[0027] S23, Generate 3D Model Based on the boundary positions of each region (Xmin, Xmax, Ymin, Ymax, Zmin, Zmax), calculate the required number of configurations in each of the three directions (X, Y, Z) for each region: Nx = floor((Xmax - Xmin) / 10), Ny = floor((Ymax - Ymin) / 10), Nz = floor((Zmax - Zmin) / 10). For example... Figure 5 As shown, each region is filled with a configuration and then the corresponding 3D model is output.

[0028] S3, Construction of the crash beam S31, Component fabrication Based on the data from the three-dimensional model in S2, three-dimensional lattice configuration preforms corresponding to each region are prepared using technologies such as continuous fiber 3D printing or three-dimensional weaving.

[0029] S32, Curing and Molding Apply adhesive to the outer wall of the metal insert and insert it into the reserved position in area A3. Then, lay a predetermined number of layers of carbon fiber / epoxy resin prepreg on each surface of the preform to form a whole covered by skin.

[0030] The assembled assembly is placed on a single-sided mold, covered with a release film and a breathable felt, and then sealed with a vacuum bag. The sealed assembly is then placed in an autoclave, evacuated, and cured under heat and pressure according to a pre-set process curve. After curing, the assembly is cooled, depressurized, removed from the autoclave, and demolded to obtain a crash beam with an integrated skin and three-dimensional lattice components.

[0031] like Figure 6As shown, the outer periphery of the metal insert 1 is designed with anchoring structures such as annular grooves and knurling to make its adhesion to the preform of the composite core material stronger. At the same time, when laying the prepreg, the number of skin layers near the metal insert 1 is 1.5 to 2.5 times that of other parts, so as to form a local thickening zone and improve the connection strength at the metal insert 1.

[0032] The above embodiments are for illustrative purposes only and are not intended to limit the invention. Those skilled in the art can make various changes or modifications without departing from the spirit and scope of the invention. Therefore, all equivalent technical solutions should also fall within the protection scope of the invention, which should be defined by the claims.

Claims

1. A method for molding an automotive anti-collision beam based on a three-dimensional lattice composite material, characterized in that: Includes the following steps: S1, Create a three-dimensional lattice configuration within a limited space, extending to the edge of the limited space, and establish a database of each configuration and its corresponding performance parameters; S2, based on the performance requirements of the crash beam, divide the crash beam into multiple functional areas along its length, and select the required three-dimensional lattice configuration from S1 to fill each area according to the performance of each area, thus filling the space of each area, forming a three-dimensional model of the crash beam and outputting it. S3, based on the three-dimensional model output from S2, processes the preforms of the three-dimensional lattice configuration required for each region, places metal inserts inside the preforms, covers the preforms with skin, and solidifies them into a crash beam.

2. The method for forming an automotive anti-collision beam based on three-dimensional lattice composite materials as described in claim 1, characterized in that: In S1, when creating a three-dimensional lattice configuration, the element size is first selected for each configuration. The element size includes the outer diameter of the rod-shaped element and the thickness of the plate-shaped element.

3. The method for forming an automotive anti-collision beam based on three-dimensional lattice composite materials as described in claim 1, characterized in that: In S1, the configurations include BCC, BCC-Z, FCC, Pyramid, and Octet structures. Among them, BCC is a body-centered cubic structure with the center of the cube connected to the eight corner points; BCC-Z is a Z-direction reinforced body-centered cubic structure with Z-direction vertical bars added on the basis of BCC; FCC is a face-centered cubic structure with the six face centers connected to the adjacent corner points; Pyramid is a pyramid-shaped structure with periodic arrangement of four-sided pyramidal units; and Octet is an octahedral tetrahedral structure composed of BCC and FCC.

4. The method for forming an automotive anti-collision beam based on a three-dimensional lattice composite material as described in claim 1, characterized in that: In S1, the finite element analysis method is used to apply standard boundary conditions to each three-dimensional lattice configuration and calculate the corresponding performance parameters; or the actual processing and experimentation are used to obtain the performance parameters. The standard boundary conditions applied are: fixing the lower surface of the three-dimensional lattice configuration, applying a load on the upper surface, causing the three-dimensional lattice configuration to produce a 1% strain.

5. The method for forming an automotive anti-collision beam based on a three-dimensional lattice composite material as described in claim 4, characterized in that: Performance parameters include: relative density, equivalent elastic modulus, equivalent yield strength, and energy absorption characteristics.

6. The method for forming an automotive anti-collision beam based on three-dimensional lattice composite materials as described in claim 1, characterized in that: In S2, the crash beam is divided into three functional areas and five parts along its length: one A1 area, two A2 areas, and two A3 areas. The A1 area is located in the middle of the crash beam and is the central energy absorption area, accounting for 40% of the total length. The A3 areas are located at both ends of the crash beam and are the end installation areas, each accounting for 10% of the total length. The A2 areas are located between the central energy absorption area and the end installation areas and are the transition areas, each accounting for 20% of the total length.

7. The method for forming an automotive anti-collision beam based on a three-dimensional lattice composite material as described in claim 1, characterized in that: In S2, the specific method for filling each region with three-dimensional lattice configurations is as follows: First, based on the boundary dimensions of each region and the side length of the selected configuration, the number of configurations required in each direction in the three-dimensional space of each region is calculated; then, the selected configurations are filled into the corresponding regions according to the calculated number to form a three-dimensional model.

8. The method for forming an automotive anti-collision beam based on a three-dimensional lattice composite material as described in claim 7, characterized in that: Design the reserved positions for placing metal inserts on the 3D model located at the connection point of the crash beam.

9. The method for forming an automotive anti-collision beam based on a three-dimensional lattice composite material as described in claim 8, characterized in that: In S3, the metal insert has an anchoring structure on its surface, and adhesive is applied to the outside of the metal insert before it is placed in the reserved position; the number of skin layers on the outside of the metal insert and its adjacent positions is 1.5 to 2.5 times the number of skin layers in other positions.

10. The method for forming an automotive anti-collision beam based on a three-dimensional lattice composite material as described in claim 1, characterized in that: In S3, the skin is made of carbon fiber / epoxy resin prepreg. During co-curing, the encapsulated whole is first sealed in a vacuum bag, and then the sealed whole is placed in a thermostatic precipitator. After vacuuming, it is heated, pressurized and kept warm for curing. After completion, it is cooled and depressurized.

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