CN-122021084-A - Structural characteristic analysis method of bionic spiral-arranged fiber reinforced composite material

CN122021084ACN 122021084 ACN122021084 ACN 122021084ACN-122021084-A

Abstract

The invention discloses a structural characteristic analysis method of a bionic spiral-arranged fiber reinforced composite material, which comprises the steps of S1, establishing a continuous medium mechanical model of a single-layer composite material, calculating elastic modulus, transverse elastic modulus and shear modulus along the fiber direction, S2, establishing a fracture energy prediction model of a multi-layer spiral laminated structure, S3, establishing an ultimate tensile strength prediction model under an off-axis stretching condition, S4, establishing an equivalent stiffness calculation model of the multi-layer spiral laminated structure, S5, preparing composite material samples with different fiber orientation angles and layering quantity, S6, carrying out mechanical property test, S7, correcting model parameters, S8, predicting mechanical properties under different structural parameters, and determining optimal structural parameters. According to the method, the quantitative prediction and parameter optimization of the mechanical property of the spiral laminated structure are realized by constructing the fracture energy superposition model, and the composite material with excellent fracture performance is designed based on the method.

Inventors

MO HU
SHAN WUBIN
PENG QIMING
ZHAO HONGXU
LI YING

Assignees

湖南电气职业技术学院

Dates

Publication Date: 20260512
Application Date: 20260416

Claims (9)

1. The structural characteristic analysis method of the bionic spiral-arranged fiber reinforced composite material is characterized by comprising the following steps of: Step S1, establishing a continuous medium mechanical model of a single-layer composite material, and calculating the elastic modulus, the transverse elastic modulus and the shear modulus along the fiber direction; S2, based on Griffith energy criterion, building a fracture energy prediction model of the multilayer spiral laminated structure, and decomposing the fracture energy into three parts of matrix fracture energy, interface dissipation energy and fiber fracture energy, wherein the interface dissipation energy item represents energy dissipation caused by interlayer angle mismatch; S3, establishing an ultimate tensile strength prediction model under an off-axis tensile condition based on a Tsai-Hill failure criterion; s4, establishing an equivalent stiffness calculation model of the multilayer spiral laminated structure based on a classical lamination theory; step S5, designing and preparing a series of composite material samples with different fiber orientation angles and layering numbers, wherein the samples comprise a single-layer reinforced structure and a multi-layer spiral laminated structure; s6, carrying out mechanical property test on the prepared series of samples to obtain a force-displacement response curve, and calculating experimental values of elastic modulus, ultimate tensile strength and breaking energy; step S7, comparing and verifying the experimental value with the theoretical predicted value in the steps S1-S4, and correcting the model parameters; and S8, predicting mechanical properties under different structural parameters based on the verified theoretical model, and determining structural parameters which enable the fracture energy and the ultimate tensile strength to be synergistically optimal.
2. The method according to claim 1, wherein the single-layer reinforcing structure has 4 samples having fiber orientation angles of 0 °, 15 °, 30 ° and 45 °, and the multi-layer spiral laminated structure has 4 samples each having 5 layers and an interlayer rotation angle Fixed at 0 °, 15 °, 30 °, and 45 °, respectively, and is for an interlayer rotation angle The 1 st layer of the sample has a fiber orientation angle of 0 DEG and the 2 nd layer of the sample is Layer 3 is 2 Layer 4 is 3 Layer 5 is 4 。
3. The method of claim 1, wherein the mechanical property test is carried out by uniaxial stretching at a loading rate of 1 mm/min, the geometric dimensions of the sample are 60 mm ×30 mm ×2mm, and the depths and widths of the central pre-gaps are 5 mm.
4. The method according to claim 1, wherein the formulas for calculating the elastic modulus in the fiber direction, the transverse elastic modulus and the shear modulus in the step S1 are: ; ; ; wherein: Is the elastic modulus in the fiber direction, in GPa; is the elastic modulus of the fiber, and the unit is GPa; the elastic modulus of the UV resin is in GPa; Is fiber volume fraction, dimensionless; Is the fiber orientation angle in degrees; Is transverse elastic modulus, unit GPa; shear modulus in GPa; is the shear modulus of the fiber, and is in GPa; Is the shear modulus of the UV resin, and is expressed in GPa.
5. The method according to claim 4, wherein the fracture energy prediction model in step S2 is: ; wherein: Is the breaking energy of a five-layer spiral laminated structure, and is in units of kJ/m2; The unit is kJ/m2, which is the cracking energy of the matrix; The tensile strength of the fiber is expressed in MPa; is a single-layer thickness, and is in mm; Interfacial shear stress of the ith layer, unit MPa; is the shear modulus of the i-th layer in GPa.
6. A bionic spiral fiber reinforced composite material is characterized by comprising a plurality of reinforcing layers and UV curable resin matrix layers, wherein the reinforcing layers are UV curable resin layers containing reticular glass fibers, the matrix layers are UV curable resin layers without glass fibers, and adjacent reinforcing layers are rotationally paved in the same direction at a fixed angle to form a spiral laminated structure with periodical orientation change.
7. The composite material according to claim 6, wherein the fixed angle is 15 degrees, 30 degrees or 45 degrees, the number of the layers is 1-10, and the glass fiber is of an in-plane continuous network structure.
8. A method of making the composite of claim 6, comprising the steps of: step P1, carrying out sample modeling by adopting three-dimensional modeling software, and exporting an STL format file; step P2, slicing by using slicing software to generate a printing control code; step P3, adopting photo-curing 3D printing equipment, taking UV curable resin as a matrix, printing layer by layer, and uniformly setting the layer thickness to be 50 mu m; Step P4, paving a layer of reticular glass fiber after six layers of UV curable resin are continuously printed, and rotating the main direction of the fiber layer by layer according to a preset spiral structure; step P5, ultraviolet irradiation is carried out to realize layer-by-layer curing, the single-layer curing time is 10 s, and the bottom layer curing time is 30 s; And P6, repeating the steps P4-P5 until the number of layers and the rotation angle are designed, and forming the spiral laminated structure.
9. The method of claim 8, wherein the photo-cured 3D printing device has a wavelength of 405 nm and a pixel resolution of 22 μm.

Description

Structural characteristic analysis method of bionic spiral-arranged fiber reinforced composite material Technical Field The invention belongs to the technical field of composite material performance analysis and structural design, and particularly relates to a structural characteristic analysis method of a bionic spiral-arranged fiber reinforced composite material. Background UV curable resin (CG) has important application value in additive manufacturing and precision molding fields due to its fast photopolymerization characteristics, high molding accuracy and good processing adaptability. However, its highly crosslinked molecular network structure results in a material with limited fracture toughness and energy dissipation capability, which is susceptible to brittle failure under impact load or crack-dominated failure conditions, severely limiting its further expansion in structural and load-bearing applications. Aiming at the brittleness problem of the UV curable resin, the existing toughening strategies comprise molecular structure modification, rubber phase toughening, nano filler introduction and the like, and although the ductility or impact property of the material is improved to a certain extent by the method, the cooperative improvement of the tensile strength and the fracture toughness is difficult to realize, and the problems of processing complexity, curing efficiency reduction and the like are easily introduced in the high filler content or complex modification process. This shows that it is difficult to fundamentally solve the bottleneck of breaking properties of UV curable resins depending on material composition regulation alone. Fiber reinforcement strategies based on structural design provide an engineering viable approach for improving polymer fracture properties. In nature, butterfly wing scales realize stress dispersion and crack retardation through a periodically arranged multilayer sheet structure, and a bionic teaching is provided for the design of high-toughness composite materials, as shown in figures 1-3. However, how to quantitatively analyze the mechanical behavior of the bionic spiral structure and build an accurate prediction model is still a technical problem in the field. The existing analysis method mostly adopts experimental trial and error, lacks theoretical modeling means of a system, and is difficult to realize the optimal design of structural parameters. Disclosure of Invention Aiming at the problems in the prior art, the invention aims to provide a structural characteristic analysis method of a bionic spiral-arrangement fiber reinforced composite material, which realizes quantitative prediction and parameter optimization of mechanical properties of a spiral laminated structure by constructing a fracture energy superposition model, and designs the composite material with excellent fracture properties based on the method. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: A structural characteristic analysis method of a bionic spiral-arranged fiber reinforced composite material comprises the following steps of sequentially carrying out S1 of establishing a continuous medium mechanical model of a single-layer composite material, calculating elastic modulus, transverse elastic modulus and shear modulus along the fiber direction, S2 of establishing a fracture energy prediction model of a multi-layer spiral laminated structure based on Griffith energy criteria, decomposing the fracture energy into three parts of matrix fracture energy, interface dissipation energy and fiber fracture energy, wherein the interface dissipation energy represents energy dissipation caused by mismatch of angles between layers, S3 of establishing an ultimate tensile strength prediction model under an off-axis tensile condition based on Tsai-Hill fracture criteria, S4 of establishing an equivalent stiffness calculation model of the multi-layer spiral laminated structure based on classical lamination theory, S5 of designing and preparing a series of composite material samples with different fiber orientation angles and layering numbers, wherein the samples comprise the single-layer reinforced structure and the multi-layer spiral structure, S6 of carrying out mechanical property test on the prepared series samples, obtaining force-displacement response curves, calculating values of the elastic modulus, ultimate tensile strength and fracture energy, S7 of carrying out experimental correction on the mechanical property test results of the series samples, and carrying out experimental parameter correction on the stress-displacement response curves after the step 7 of the step 7 and the theoretical tensile strength prediction model under the theoretical tensile strength and the theoretical tensile strength prediction model are verified and the theoretical strength is not verified. As a further improvement of the above technical scheme: The single-layer rei