A rod-based porous biomimetic scaffold with dual regulation parameters and a design method thereof

Abstract

A rod-based porous biomimetic scaffold with dual adjustable parameters and its design method are disclosed. The method involves designing basic units based on Primitive units in a typical TPMS lattice; solving the volume fraction function expression based on the geometric relationships of the basic units; determining the volume fraction of the basic units for practical application according to the target scaffold and obtaining the dual adjustable parameters; establishing a three-dimensional model of the basic unit array arranged as a porous structure and 3D printing the rod-based porous biomimetic scaffold; and evaluating the mechanical properties and mass transfer performance of the rod-based porous biomimetic scaffold. The inclusion of two independently adjustable parameters—the diameters of the main and secondary load-bearing rods—enables a high degree of decoupling between its mechanical properties and mass transfer performance, giving the scaffold structure more possibilities.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of porous biomimetic scaffolds, especially a kind of rod base porous biomimetic scaffolds with double adjustment parameters and its design method, belong to bone tissue engineering technical field. BACKGROUND

[0002] In the field of bone tissue engineering, bone scaffold as autologous bone transplantation or allogeneic bone transplantation substitute, provides mechanical support and supports bone regeneration in the implanted defect site. Therefore, the bone scaffold should have interconnected pores to promote the adhesion, proliferation and nutrient transport of tissue cells, while showing similar mechanical properties to the surrounding tissue of the implanted site.

[0003] Mechanical properties and mass transport properties are two important indicators for measuring bone scaffolds, and appropriate mechanical stimulation can effectively promote bone regeneration, so the mechanical properties (elastic modulus and strength) of the ideal bone scaffold should match the implanted site. If the strength of the scaffold is too high, it will lead to the generation of stress shielding phenomenon, resulting in mechanical loosening of the contact interface between the scaffold and the bone tissue. Conversely, if the strength of the scaffold is too low, it may lead to bone resorption. Mass transport properties reflect the ability of the scaffold to transport tissue fluid, and the topological characteristics, mechanical properties and fluid properties of human bone are closely related to the site where the bone is located, so the ideal bone scaffold should have flexible and adjustable topological properties to meet the performance requirements of different sites. However, in the design process of bone scaffolds, in order to obtain excellent mechanical properties, the porosity is often reduced, which will lead to a decrease in mass transport capacity. Conversely, if the porosity is increased, it cannot guarantee excellent mechanical properties. Therefore, when designing porous biomimetic scaffolds, the relationship between porosity, mechanical properties and mass transport properties should be balanced, and the mechanical properties of the scaffold should match the surrounding tissue, while the scaffold should also have optimal permeability at appropriate porosity to ensure the proliferation of tissue cells and the transport of nutrients.

[0004] However, current scholars' research on scaffold structure mostly focuses on only one performance, such as some scholars focusing on the mechanical properties of the scaffold, optimizing the design to match the mechanical properties of the surrounding tissue of the implanted site; other scholars focus on the influence of scaffold porosity and topological characteristics on mass transport properties. However, both of these performances are crucial for porous scaffolds, although the simultaneous optimization of mechanical properties and mass transport properties has attracted the attention of some scholars, but the situation that these two performances are mutually restrictive in terms of porosity requirements has not been well solved at this stage, leading to the urgent demand for porous biomimetic scaffolds with excellent comprehensive performance in the field of bone tissue engineering. SUMMARY

[0005] To address the shortcomings of the prior art, this invention provides a rod-based porous biomimetic support with dual adjustable parameters and its design method. It includes two independently adjustable parameters: the diameters of the main and auxiliary load-bearing rods. This enables a high degree of decoupling between its mechanical properties and mass transfer performance, giving the support structure more possibilities.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A rod-based porous biomimetic scaffold with dual adjustable parameters includes several porous structures formed by an array of basic units. The basic units are simplified from Primitive units in a typical TPMS lattice. The spatial symmetry axis of the Primitive unit and the curved surface structure corresponding to the outer edge of the spatial symmetry axis are extracted. A main load-bearing rod is set at the position of the spatial symmetry axis. The curved surface structure corresponding to the outer edge of the spatial symmetry axis is simplified into a line segment between the spatial symmetry axes. A secondary load-bearing rod is set at the position of the simplified line segment. The diameter D of the main load-bearing rod and the diameter d of the secondary load-bearing rod are used as dual adjustable parameters.

[0008] A design method for a rod-based porous biomimetic scaffold with dual adjustable parameters includes the following steps:

[0009] Step 1: Design basic units based on the Primitive units in a typical TPMS lattice;

[0010] Step 2: Based on the geometric relationships of the basic unit, solve for its volume fraction function expression as follows:

[0011]

[0012] In the formula, V _PST L is the volume fraction of the basic unit, L is the side length of the cube containing the basic unit, and L1 is the distance between two nodes on the main load-bearing rod that are shared with the secondary load-bearing rod.

[0013] Step 3: Determine the volume fraction of the basic unit for actual application based on the target support and obtain the dual adjustment parameters;

[0014] Step 4: Establish a three-dimensional model of the basic unit array arranged in a porous structure, and 3D print the rod-based porous biomimetic scaffold;

[0015] Step 5: Evaluate the mechanical properties and mass transfer performance of the rod-based porous biomimetic scaffold. Elastic modulus and permeability are selected as indicators for evaluating mechanical properties and mass transfer performance, respectively.

[0016] The formula for calculating the elastic modulus is:

[0017]

[0018] In the formula, F is the reaction force, L0 is the side length of the support, A is the cross-sectional area of ​​the support, and U is the deformation of the support in the direction of the force.

[0019] Permeability is calculated using Darcy's Law, and its expression is:

[0020]

[0021] In the formula, k represents the permeability coefficient, H0 represents the height of the support, which is equal to the side length of the support, v represents the fluid velocity, μ represents the dynamic viscosity coefficient of the fluid, and ΔP represents the pressure drop of the entire model.

[0022] The above indicators are evaluated based on the simulation results. The reliability of the simulation results is verified by compression experiments and compared and analyzed with existing data. If the mechanical properties and mass transfer performance of the fabricated rod-based porous bionic scaffold meet the requirements of the target scaffold, it can be further shaped and processed for practical application. If not, the dual adjustment parameters are readjusted and the rod-based porous bionic scaffold is fabricated again.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: The Primitive unit in the typical TPMS lattice of the present invention creates the basic unit, which includes two independently adjustable parameters: the diameter of the main and secondary load-bearing rods. It achieves a high degree of decoupling of elastic modulus and permeability at a given porosity, and does not sacrifice mass transfer performance while possessing excellent mechanical properties. It has the ability to independently customize mechanical properties and mass transfer performance. At the same time, the dual adjustable parameters enrich the types of scaffold structures, giving scaffold structures more possibilities, and the performance adjustment of scaffold structures is also more convenient and flexible. It not only provides an effective means to construct scaffold structures that meet specific mechanical and fluid performance requirements, but also highlights the application value of customized design in the field of bone tissue engineering. Attached Figure Description

[0024] Figure 1 This is a schematic diagram illustrating the evolution of the basic unit of the rod-based porous biomimetic scaffold of the present invention;

[0025] Figure 2 This is a schematic diagram of the porous structure obtained by arranging the basic units of the present invention in a 3×3×3 matrix;

[0026] Figure 3 This is a comparison chart of the basic unit theory and the volume fraction measured by the software in the embodiment;

[0027] Figure 4 These are the stress-strain curves of the rod-based porous biomimetic scaffold obtained from compression tests in the embodiments;

[0028] Figure 5 It is the elastic modulus value of the rod-based porous bionic scaffold obtained from simulation and experiment in the embodiment;

[0029] Figure 6 Part a shows the variation of the elastic modulus of the rod-based porous biomimetic scaffold with volume fraction in the embodiment.

[0030] Figure 6 Part b shows the variation of permeability and pressure drop with porosity of the rod-based porous biomimetic scaffold in the embodiment;

[0031] Figure 7 Part a is a design diagram of the combination of elastic modulus and permeability of the rod-based porous biomimetic scaffold in the embodiment;

[0032] Figure 7 Part b is a comparison diagram of the deformation mechanism of the basic unit PST in the embodiment and a typical porous scaffold. Detailed Implementation

[0033] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0034] Reference Figures 1-2 As shown, a rod-based porous biomimetic support with dual adjustable parameters includes several porous structures formed by an array of basic units. The basic units are simplified from Primitive units in a typical TPMS lattice, retaining their main load-bearing structures to create the basic unit in this scheme, referred to as PST. Specifically, the spatial symmetry axis of the Primitive unit and the corresponding curved surface structure on the outer edge of the spatial symmetry axis are extracted. A main load-bearing rod is placed at the spatial symmetry axis position. The curved surface structure on the outer edge of the spatial symmetry axis is topologically optimized and simplified into line segments between the spatial symmetry axes. Secondary load-bearing rods are placed at the simplified line segment positions. This makes the basic unit a rotationally symmetric structure composed of three main load-bearing rods and eight secondary load-bearing rods, exhibiting isotropic characteristics. The three main load-bearing rods pass through the body center of the basic unit, with two main load-bearing rods intersecting perpendicularly in the horizontal plane, and the remaining main load-bearing rod passing vertically through its intersection point. Eight secondary load-bearing rods are arranged symmetrically about the body center of the basic unit. Each pair of adjacent main load-bearing rods is connected to a secondary load-bearing rod at their nearest end points. The diameter D of the main load-bearing rods ranges from 1.6 to 1.8 mm with an interval of 0.1 mm, and the diameter d of the secondary load-bearing rods ranges from 0.8 to 1.6 mm with an interval of 0.2 mm, and D / d > 1. The diameters D of the main load-bearing rods and d of the secondary load-bearing rods are used as the dual adjustment parameters of the porous bionic support for the rod base in this design.

[0035] Reference Figures 1-3As shown, a design method for a rod-based porous biomimetic scaffold with dual adjustable parameters includes the following steps:

[0036] Step 1: Design basic units based on the Primitive units in a typical TPMS lattice, combined with... Figure 1 As shown;

[0037] Step 2: Solve for the volume fraction function expression based on the geometric relationships of the basic unit.

[0038] Because the main and secondary load-bearing members of the basic element contain multiple overlapping shared nodes, the simplified volume fraction expression for the basic element considering the overlapping region is as follows:

[0039]

[0040] In the formula, V _PST Let D be the volume fraction of the basic element, d be the diameter of the main load-bearing member, d be the diameter of the secondary load-bearing member, L be the side length of the cube containing the basic element, and L1 be the distance between two nodes on the main load-bearing member that share nodes with the secondary load-bearing member. Figure 2 As shown.

[0041] Furthermore, the volume fraction V of the basic unit can be used as a basis. _PST Calculate the porosity p, p = 1 - V _PST Based on the porosity p, the basic unit is designed according to the requirements of the target support.

[0042] Step 3: Determine the volume fraction of the basic unit for actual application based on the target support and obtain the dual adjustment parameters.

[0043] The diameters D of the main load-bearing rods and d of the secondary load-bearing rods conform to the following principles: the diameter D of the main load-bearing rods ranges from 1.6 to 1.8 mm, with an interval of 0.1 mm; the diameter d of the secondary load-bearing rods ranges from 0.8 to 1.6 mm, with an interval of 0.2 mm; and D / d > 1. Based on the target support, determine the actual volume fraction of the basic unit for application, and then, according to the volume fraction V in step two... _PST The expression determines the specific values ​​of the diameter D of the main load-bearing member and the diameter d of the secondary load-bearing member;

[0044] Step 4: Establish a three-dimensional model of the basic unit array arranged in a porous structure, and use selective laser melting (SLM) technology to prepare 3D printed rod-based porous biomimetic scaffolds;

[0045] Step 5: Evaluate the mechanical properties and mass transfer performance of the rod-based porous biomimetic scaffold.

[0046] Finite element analysis and hydrodynamic simulations were performed on a rod-based porous biomimetic scaffold. Elastic modulus and permeability were selected as indicators to evaluate mechanical properties and mass transfer performance, respectively. The simulation results were used to evaluate these indicators, and compression experiments were conducted to verify the reliability of the simulation results. The results were then compared and analyzed with existing data.

[0047] The formula for calculating the elastic modulus is:

[0048]

[0049] In the formula, F is the reaction force (Pa), L0 is the side length of the support (m), and A is the cross-sectional area of ​​the support (m²). 2 U is the deformation of the support in the direction of force (m).

[0050] Permeability can be calculated using Darcy's Law, and its expression is as follows:

[0051]

[0052] In the formula, k represents the permeability coefficient (m 2 H0 represents the height of the support, which is equal to the side length of the support (m), v represents the fluid velocity (m / s), μ represents the dynamic viscosity coefficient of the fluid (Pa·s), and ΔP represents the pressure drop of the entire model (Pa).

[0053] If the mechanical properties and mass transfer performance of the fabricated rod-based porous bionic scaffold meet the requirements of the target scaffold, then subsequent shaping and processing can be carried out for practical application. If not, the dual adjustment parameters should be readjusted and the rod-based porous bionic scaffold should be fabricated again.

[0054] Example

[0055] This embodiment is based on the proposed rod-based porous biomimetic scaffold structure with dual adjustable parameters. It can be widely used in bone tissue scaffolds for different defect sites. It has dual adjustable parameters for the diameter D of the main load-bearing rod and the diameter d of the secondary load-bearing rod, which can realize the customized design of scaffold performance. The design method includes the following steps:

[0056] Step 1: Design and construct the basic unit of the rod-based porous biomimetic scaffold. Primitive units from a typical TPMS lattice are selected to simplify their spatial structure, retaining their main load-bearing structure to create the basic unit in this scheme. Figure 1 As shown, the spatial symmetry axis of the Primitive unit and the surface structure corresponding to the outer edge of the spatial symmetry axis are extracted as the main load-bearing rod and the secondary load-bearing rod, respectively, thus obtaining a basic unit structure with symmetry;

[0057] Step 2: Solve for the volume fraction function expression based on the geometric relationships of the basic element. Because the main and secondary load-bearing members of the basic element contain multiple overlapping shared nodes, the simplified volume fraction expression for the basic element considering the overlapping region is as follows:

[0058]

[0059] In the formula, V _PST Let D be the volume fraction of the basic element, d be the diameter of the main load-bearing member, d be the diameter of the secondary load-bearing member, L be the side length of the cube containing the basic element, and L1 be the distance between two nodes on the main load-bearing member that share nodes with the secondary load-bearing member. Figure 2 As shown, and can be determined based on the volume fraction V of the basic unit. _PST Calculate the porosity p, p = 1 - V _PST Based on the porosity p, the basic unit is designed according to the requirements of the target support.

[0060] Step 3: Determine the volume fraction of the basic unit for actual application based on the target support and obtain the dual adjustment parameters. Considering the principle that D / d > 1, the diameter ranges of the main load-bearing rods and secondary load-bearing rods are established. Specifically, the diameter D of the main load-bearing rods ranges from 1.6 to 1.8 mm with an interval of 0.1 mm, and the diameter d of the secondary load-bearing rods ranges from 0.8 to 1.6 mm with an interval of 0.2 mm.

[0061] Table 1 shows the basic unit structures corresponding to different diameter parameters, where D1.6d1.0 represents a basic unit structure with a main load-bearing rod diameter of 1.6mm and a secondary load-bearing rod diameter of 1.0mm.

[0062] Table 1 Geometric characteristics of basic unit structures

[0063]

[0064] Combination Figure 3 The figure shows a comparison between the theoretical volume fraction of the basic unit structure and the volume fraction measured in CAD software. It can be seen that the maximum deviation is 0.64%, indicating that the simplified volume fraction expression proposed in this application is reliable. Furthermore, Table 1 shows that the porosity range of the basic unit structure is 80%–90%, which is consistent with the porosity range of human cancellous bone.

[0065] Step 4: Establish a 3D model and 3D print a rod-based porous biomimetic scaffold. Based on the parameters in Table 1, a 3D model was established, and a sample of the rod-based porous biomimetic scaffold was fabricated using the SLM system (SLM280). The parameters for 3D printing were set as follows: laser power 300W, scanning speed 1250mm / s, dust thickness 30μm, processing temperature 150℃, and the maximum deviation of the volume fraction of the 3D printed sample from the theoretical value was 2.8%.

[0066] Step 5: Evaluate the performance of the rod-based porous biomimetic scaffold. The mechanical properties and mass transfer performance of the rod-based porous biomimetic scaffold are obtained using finite element analysis and fluid dynamics simulation. Elastic modulus and permeability are selected as evaluation indicators. The formula for calculating the elastic modulus is:

[0067]

[0068] In the formula, F is the reaction force (Pa), L0 is the side length of the support (m), and A is the cross-sectional area of ​​the support (m²). 2 U is the deformation of the support in the direction of force (m).

[0069] Permeability can be calculated using Darcy's Law, and its expression is as follows:

[0070]

[0071] In the formula, k represents the permeability coefficient (m 2 H0 represents the height of the support, which is equal to the side length of the support (m), v represents the fluid velocity (m / s), μ represents the dynamic viscosity coefficient of the fluid (Pa·s), and ΔP represents the pressure drop of the entire model (Pa).

[0072] After obtaining the elastic modulus and permeability parameters of the rod-based porous biomimetic scaffold, the simulation results were verified through experiments. The performance of the rod-based porous biomimetic scaffold was then compared and evaluated by combining existing performance data with the target performance of bone tissue. This process verifies the reliability of the simulation results and assesses the superior performance of the rod-based porous biomimetic scaffold. The performance evaluation focuses on its ability to balance mechanical properties and mass transfer performance, and whether it can achieve customized designs that achieve both of these performance characteristics.

[0073] Performance evaluation results show that the rod-based porous biomimetic scaffold designed in this invention can achieve an elastic modulus range of 0.58–4.12 GPa and a permeability range of 2.4 × 10⁻⁶. -7 -3.47×10 -7 m 2All of these results are consistent with the performance range of human cancellous bone. Furthermore, the maximum deviation between the experimentally obtained elastic modulus and the simulation results is 10.6%, and the simulated permeability range is basically consistent with existing scaffold structures, proving that the performance evaluation results of the rod-based porous biomimetic scaffold designed in this invention are reliable.

[0074] Based on the optimization results obtained from the above steps, combined with Figures 4-7 As shown, the specific conclusions are as follows:

[0075] Combination Figure 4 The figure shows the stress-strain curve of the rod-based porous bionic scaffold obtained from the compression test. The elastic modulus can be obtained from the slope of the stress-strain curve in the first linear stage, and the simulation results are verified.

[0076] Combination Figure 5 The figure shows the elastic modulus values ​​of the rod-based porous bionic scaffold obtained through simulation and experiment. It can be seen that the error of the simulation and experimental results is within an acceptable range. This error is caused by insufficient manufacturing precision of the sample. During the printing process, factors such as printing speed and processing temperature will affect the manufacturing precision of the sample.

[0077] Combination Figure 6 The figure shows the variation of the elastic modulus of the rod-based porous biomimetic scaffold with volume fraction. Figure 6 a) and the variation of permeability and pressure drop with porosity ( Figure 6 b). By Figure 6 As can be seen from a, with the increase of the diameter of the main load-bearing rod, the volume fraction of the porous biomimetic support base increases accordingly. When the diameter of the main load-bearing rod is 1.8 mm, the corresponding D1.8d1.6 structure has the largest elastic modulus value, which is 4.12 GPa. Figure 6 As shown in b, the effects of porosity on permeability and pressure drop are opposite. As porosity increases, the permeability of the rod-based porous biomimetic scaffold is enhanced, and the pressure drop decreases accordingly.

[0078] Combination Figure 7 The diagram shown is a design diagram of the combination of elastic modulus and permeability of a rod-based porous biomimetic scaffold. Figure 7 a) and a comparison diagram of the deformation mechanisms of the basic unit PST and a typical porous scaffold ( Figure 7 b). By Figure 7As shown in Figure a, under the same volume fraction level, rod-based porous biomimetic scaffold structures with different elastic moduli (or strengths) and permeabilities can be obtained. Combined with Figures A1-B1, this indicates that the structure can achieve customized design of elastic modulus and permeability at a given volume fraction. In this case, the mechanical and fluid properties of the structure are not only affected by the volume fraction but also related to the topological characteristics of the structure. Therefore, the rod-based porous biomimetic scaffold with dual adjustable parameters proposed in this invention can effectively solve the problem of mutual constraints between the mechanical and fluid properties of porous scaffolds in terms of volume fraction requirements. For a given volume fraction, the elastic modulus and permeability can be independently customized by adjusting the diameters of the main and secondary load-bearing rods. By adjusting the dual adjustable parameters D and d, the permeability changes while the macroscopic mechanical properties remain essentially unchanged, and vice versa.

[0079] Compared to traditional homogeneous porous structures, the structure proposed in this invention possesses more structural parameters and a stronger ability to comprehensively adjust mechanical and mass transfer properties. Therefore, it can serve as a metamaterial capable of independently adjusting the mechanical matching and appropriate permeability of certain specific bone scaffolds. Human cancellous bone was used (VF: 0.1-0.5; E: 0.1-4.5 GPa; k: 0.0003 × 10⁻⁶). -7 -0.743×10 -7 m 2 For example, the structure designed in this invention can simulate the above-mentioned characteristics of cancellous bone. Figure 7 In section b, the mechanical properties of the rod-based porous biomimetic scaffold were compared with Ashby's empirical data and existing structures. It can be observed that the mechanical properties of the rod-based porous biomimetic scaffold proposed in this invention are superior to the ideal bending-dominant behavior. Furthermore, by adjusting the dual adjustment parameters, the stiffness range of this structure is significantly increased, providing more options for its potential applications. Compared with BCC structures and the thin-shell-based Schwarz-P(SP) structure, the rod-based porous biomimetic scaffold proposed in this invention achieves a larger stiffness adjustment range, and its mechanical behavior more closely matches the ideal bending-dominant structure.

[0080] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of the equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0081] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A design method for a rod-based porous biomimetic scaffold with dual adjustable parameters, characterized in that: The rod-based porous biomimetic scaffold with dual adjustable parameters comprises several porous structures formed by an array of basic units. The basic units are simplified from Primitive units in a typical TPMS lattice. The spatial symmetry axis of the Primitive unit and the corresponding curved surface structure on the outer edge of the spatial symmetry axis are extracted. A main load-bearing rod is placed at the spatial symmetry axis position. The curved surface structure on the outer edge of the spatial symmetry axis is simplified to a line segment between the spatial symmetry axes. Secondary load-bearing rods are placed at the simplified line segment positions. The diameter of the main load-bearing rod... and the diameter of the auxiliary load-bearing rod As a dual-adjustment parameter, its design method includes the following steps: Step 1: Design basic units based on the Primitive units in a typical TPMS lattice; Step 2: Based on the geometric relationships of the basic unit, solve for its volume fraction function expression as follows: In the formula, The volume fraction of the basic unit. Let be the side length of the cube containing the basic unit. The distance between two nodes on the main load-bearing member that are shared with the secondary load-bearing member; Step 3: Determine the volume fraction of the basic unit for actual application based on the target support and obtain the dual adjustment parameters; Step 4: Establish a three-dimensional model of the basic unit array arranged in a porous structure, and 3D print the rod-based porous biomimetic scaffold; Step 5: Evaluate the mechanical properties and mass transfer performance of the rod-based porous biomimetic scaffold. Elastic modulus and permeability are selected as indicators for evaluating mechanical properties and mass transfer performance, respectively. The formula for calculating the elastic modulus is: In the formula, As a reaction force, Let the side length of the bracket be . Let the cross-sectional area of ​​the support be... This represents the deformation of the support in the direction of the applied force. Permeability is calculated using Darcy's Law, and its expression is: In the formula, Indicates penetration rate. This indicates the height of the support frame, which is equal to the side length of the support frame. Indicates fluid velocity. It represents the dynamic viscosity coefficient of a fluid. This represents the pressure drop across the entire model; The above indicators are evaluated based on the simulation results. The reliability of the simulation results is verified by compression experiments and compared and analyzed with existing data. If the mechanical properties and mass transfer performance of the fabricated rod-based porous bionic scaffold meet the requirements of the target scaffold, it can be further shaped and processed for practical application. If not, the dual adjustment parameters are readjusted and the rod-based porous bionic scaffold is fabricated again.

2. The design method of a rod-based porous biomimetic scaffold with dual adjustable parameters according to claim 1, characterized in that: The diameter of the main load-bearing rod The diameter of the secondary load-bearing rod is in the range of 1.6~1.8mm, with intervals of 0.1mm. The range is 0.8~1.6mm, with intervals of 0.2mm, and .

Images