Metal glass bionic artificial bone implant laser powder bed melting additive manufacturing method

Abstract

The invention discloses a laser powder bed melting additive manufacturing method for a metal glass bionic artificial bone implant, and belongs to the technical field of additive manufacturing technologies and biomedical materials, the laser powder bed melting technology is adopted, and microscopic structures with different porosities are formed at different positions by designing a three-dimensional model and regulating and controlling laser process parameters, so that the metal glass bionic artificial bone implant is obtained. Therefore, the integrated forming of the artificial bone implant with the gradient pore structure is realized; according to the method, from the two angles of three-dimensional modeling and process parameters, the internal pore structure of the part can be controlled in the macroscopic level, the mesoscopic level and the microcosmic level, the energy absorption capacity and the cell tissue infiltration capacity of the metal glass implant are remarkably improved, the elastic modulus of the metal glass implant can be effectively reduced, and the manufacturing cost of the metal glass implant is reduced. According to the metal glass bionic artificial bone implant, the performance of the implant is comprehensively regulated and controlled, the stress shielding effect is effectively relieved, the overall stability of the metal glass implant is enhanced, and application of the metal glass bionic artificial bone implant in human body bone defect repair clinical treatment is facilitated.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of additive manufacturing and biomedical materials, and particularly relates to a laser powder bed fusion additive manufacturing method for a metallic glass bionic artificial bone implant. BACKGROUND

[0002] Bone is one of the most transplanted tissues in the human body, with an incidence of nearly 15%, and there are millions of bone fracture cases every year. Autologous bone transplantation and non-autologous bone transplantation are two repair methods for bone transplantation. The pain, infection and immune rejection brought by autologous bone transplantation hinder its development. In this case, non-autologous bone transplantation becomes the main choice for bone transplantation, and clinical evidence shows that most ordinary bone scaffold implants lack sufficient mechanical strength and a suitable environment for vascularization. The best bone scaffold implant should have all levels of autologous bone characteristics (mechanical, biological, mass, transport and microstructure geometry) for cell penetration and nutrient diffusion and biodegradation during the service of artificial bone.

[0003] Traditional bone scaffold implant manufacturing methods include pure metal, gas foaming of metal powder, etc., which makes it only possible to control the mechanical properties of the whole artificial bone from a macroscopic point of view, but not the geometric structure from a microscopic point of view. However, the microstructure inside the artificial bone is a key factor affecting tissue regeneration; with the popularity of additive manufacturing, rapid prototyping technology has become the best technology for manufacturing three-dimensional irregular porous implants, promoting the design of artificial bone to computer-aided tissue engineering design. With advanced imaging tools, the design and manufacture of regenerative implants greatly simplify the design of artificial bone with ideal porosity, pore shape and mechanical properties.

[0004] The most common artificial bone in clinical application is dense metal, but the modulus of dense metal is much higher than that of autologous bone, and stress shielding phenomenon occurs during service, which accelerates the fatigue failure and damage of the interface between the bone implant and other tissues, and the dense metal does not leave enough space for bone ingrowth and tissue growth.

[0005] The current frontier of customized artificial bone implants mainly uses slurry direct writing and laser powder bed fusion technology, but the artificial bone implant printed by slurry direct writing has the defect of low strength, and the pore diameter of the printed part is usually in the range of 100-800 μm, which cannot restore the pore size of cortical bone; and the titanium alloy implant printed by laser powder bed fusion has the problem of too large pore size, which cannot perfectly restore the porosity of human cortical bone and cancellous bone.

[0006] Metallic glass, also known as glassy metal or amorphous metal, has the advantages of both metal and glass, with higher strength than steel, higher hardness than high-speed tool steel, and certain toughness and rigidity. Iron-based metallic glass has the potential to replace titanium alloy artificial bone implant as an excellent material due to its extremely high wear resistance, strength much higher than titanium alloy, good biocompatibility, and relatively low price. However, due to the high elastic modulus of metallic glass, using a dense block directly as an artificial bone implant will exacerbate the stress shielding effect.

[0007] In summary, in view of the low strength, high elastic modulus, poor biocompatibility, and severe stress shielding effect of existing biomimetic artificial bone implants, and the imperfect porosity and gradient design of the corresponding manufacturing technology, the present application aims to complete the additive manufacturing of metallic glass biomimetic artificial bone implants through laser powder bed fusion process, design from two directions of three-dimensional model and process parameters, control the internal pore structure of the part at macro, meso, and micro levels, and reduce the elastic modulus of the metallic glass printed part by increasing the porosity, so as to match the modulus of the human body bone, effectively alleviate the stress shielding effect, and finally realize the manufacturing of a biomimetic artificial bone implant with lower elastic modulus, higher strength, and completely controllable internal pore structure. SUMMARY

[0008] The purpose of the present application is to solve the problems of insufficient strength of existing artificial bone implants, incomplete internal micro-pore structure and gradient structure, and to provide a laser powder bed fusion additive manufacturing method for metallic glass biomimetic artificial bone implants.

[0009] The laser powder bed fusion additive manufacturing method for metallic glass biomimetic artificial bone implants has the following specific steps:

[0010] Step 1: Preparing metallic glass powder with a particle size of 30-50 μm;

[0011] Step 2: Determining the geometric shape of the metallic glass biomimetic artificial bone implant according to the clinical and mechanical performance requirements, and designing the pore structure distribution according to the macro (> 500 μm), meso (100-500 μm), and micro (< 100 μm) levels;

[0012] Step 3: Using three-dimensional modeling software to model the metallic glass biomimetic artificial bone implant, the macro-pore structure of the implant adopts a random gradient pore structure based on a density-adjustable three-dimensional space lattice; by adjusting the density gradient of the lattice, the required gradient macro-pore structure is generated;

[0013] The density gradient of the point array is generated by randomly removing points according to distance, that is, a certain number of uniformly distributed point arrays are first generated, and points closer to the center of the model have a greater probability of being removed to generate a point array with a density gradient;

[0014] Suppose the probability of each point in the point array being removed is:

[0015] (1)

[0016] Wherein, is the distance of the point relative to the reference surface (zero point), assuming that the points are sufficient, then the distribution function of the point array density is:

[0017] (2)

[0018] Wherein, is the distance of the highest point of the point array generation area relative to the reference surface (zero point);

[0019] If the total number of points generated in the specified point array is , when is sufficiently large, the point array density distribution function can be discretized; the point array can be considered as the probability density function:

[0020] (3)

[0021] Step 4: Design the meso and micro pore structure of the artificial bone implant, adopt the method of segmentation and reassembly, and divide the original artificial bone implant model into three sub-regions: outer layer region, middle layer region and inner layer region;

[0022] Step 5: import the model into Ansys for finite element simulation analysis, if the strength meets the clinical requirements, the current design is used, if the strength does not meet the clinical requirements, return to step 1 to redesign the pore structure distribution of the artificial bone implant;

[0023] Step 6: input the three-dimensional model files of the three sub-regions in STL format into the slicing software of the laser powder bed fusion additive manufacturing system for reassembly, set the layer thickness and scanning interval; and convert the three-dimensional data of the model into code for controlling the deflection of the galvanometer and the power of the laser, and then determine the laser power and scanning speed parameters;

[0024] Step 7: put the pre-prepared metal glass powder into the powder supply cylinder in the forming chamber, introduce high-purity argon into the working chamber, perform oxygen removal operation, and when the oxygen content reaches the permitted value, perform layer-by-layer forming of the metal glass powder of the metal glass bionic artificial bone implant;

[0025] Step 8: The compression, torsion and bending performance of the formed metallic glass bionic artificial bone implant are tested using a universal testing machine and a three-point bending tester.

[0026] If the mechanical properties meet the clinical requirements, the geometric parameters and pore formation can be performed; if the mechanical properties do not meet the clinical requirements, the pore structure distribution of the bionic artificial bone implant is redesigned.

[0027] The reference plane (zero point) can be the plane passing through the body center of the lattice generation area, the lattice density is symmetrical on both sides of the reference plane, and the following is taken:

[0028] (4)

[0029] wherein, is the distance of the selected cross section to the reference plane (zero point), is the height of the lattice generation area, and the distribution function of the lattice density is:

[0030] (5)

[0031] If N points are generated when actual modeling is considered, the continuous distribution can be discretely calculated; the lattice is symmetrically divided into n equidistant intervals in the Z-axis direction;

[0032] When the number of points is counted, the sum of the symmetrical regions on both sides of the reference plane is calculated; then in the kth interval, the expected value of the number of points remaining after the elimination process should be:

[0033] (6).

[0034] The macroscopic pore structure scheme can also use a random gradient pore structure scheme based on pore size gradient; by adjusting the pore size and pore density distribution function, the corresponding gradient pore structure is generated.

[0035] The macroscopic pore structure can use the homogenization method to construct a lattice structure with order and periodicity based on a lattice unit, adjust the pore size distribution of the lattice unit to realize a gradient pore structure, or based on a spatial three-dimensional lattice, realize a gradient pore structure by adjusting the density distribution of the spatial three-dimensional lattice without order and periodicity.

[0036] The modeling of the bionic artificial bone implant in step 1 can be completed using three-dimensional modeling software such as Catia, Solidworks, Blender, Rhino, etc.

[0037] The adjustable range of each parameter in step 6 is: the adjustable range of laser power is 0-500 W, the adjustable range of scanning speed is 0-1600 mm / s, the adjustable range of layer thickness is 30-40 mu m, and the adjustable range of scanning spacing is 70-110 mu m.

[0038] More fine micro-pore organization regulation can be realized by secondary laser scanning on the selected area.

[0039] The metal glass powder can be one or more of Pd-based, Fe-based, Zr-based, Mg-based, Al-based, Ti-based, Cu-based, Ce-based and La-based metal glass.

[0040] The application provides a laser powder bed fusion additive manufacturing method for a metal glass bionic artificial bone implant, and belongs to the technical fields of additive manufacturing and biomedical materials.

[0041] Compared with the prior art, the application has the following advantages:

[0042] (1) The application is designed from two aspects of a three-dimensional model and process parameters, and realizes control of internal pore structures of parts at three levels of macro, meso and micro, so that the precise gradient pore structures in cortical bone and cancellous bone can be completely restored.

[0043] (2) The application has more accurate porosity control than traditional methods, realizes subjective regulation of the elastic modulus of the printed bionic artificial bone implant, and effectively relieves the stress shielding effect.

[0044] (3) With the enhanced control ability of the elastic modulus of the implant, the application can introduce a material with higher strength to replace traditional titanium alloy, improves the strength and stability of the bionic artificial bone implant, breaks the performance limit of traditional artificial bone, greatly widens the design limit of the bionic artificial bone implant, and has a great auxiliary and promoting effect on clinical treatment and patient rehabilitation. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1is the forming process flow chart of the metal glass bionic artificial bone implant of the application;

[0046] Figure 2 is a rendering of another iron-based metal glass bionic leg bone artificial bone implant in embodiment 2 of the application;

[0047] Figure 3 is a rendering of another iron-based metal glass bionic leg bone artificial bone implant in embodiment 2 of the application;

[0048] Figure 4 is a schematic diagram of the macro-pore structure design of an iron-based metal glass bionic leg bone artificial bone implant in embodiment 1 of the application;

[0049] Figure 5 is a supplementary explanatory diagram of the macro-pore structure design scheme in embodiment 1 of the application;

[0050] Figure 6 is a schematic diagram of the macro-pore structure design of another iron-based metal glass bionic leg bone artificial bone implant in embodiment 2 of the application;

[0051] Figure 7 is a schematic diagram of the macro-pore structure design of another iron-based metal glass bionic leg bone artificial bone implant in embodiment 2 of the application;

[0052] Figure 8 is a rendering of the postoperative effect of the iron-based metal glass bionic leg bone artificial bone implant in embodiment 1 of the application. DETAILED DESCRIPTION

[0054] Embodiment 1:

[0055] The laser powder bed fusion additive manufacturing method of the metal glass bionic artificial bone implant of the application comprises the following specific steps:

[0056] In this embodiment, an iron-based metal glass is used to prepare a bionic bone leg artificial bone implant:

[0057] Step 1: Determine the metal glass powder. In this embodiment, a pre-prepared Fe-based (Fe-Co-Cr-Mo-C-B-Y) metal glass powder is used, and the powder particle size is 30-50 μm.

[0058] Step 2: Determine the geometric shape of the metal glass bionic artificial bone implant according to the clinical and mechanical performance requirements of the metal glass bionic artificial bone implant after forming, and design the pore structure distribution according to the macroscopic (>500 μm), mesoscopic (100-500 μm) and microscopic (<100 μm) three levels;

[0059] Step 3: Refer to the attached Figure 2In this embodiment, the metal-glass biomimetic artificial bone implant is a cylinder.

[0060] A three-dimensional model of the overall outline of the implant was created using Rhino software, and the macroscopic pore structure of the implant was modeled using the Grasshopper plugin.

[0061] The macroscopic pore structure adopts a stochastic gradient pore structure based on a density-adjustable three-dimensional spatial lattice. The lattice distribution and model performance are detailed in the appendix. Figure 4 ;

[0062] The left-side lattice corresponds to the node position of the implant on the right side. Here, to clearly show the macroscopic pore gradient, a lattice density gradient along the axial direction is used only.

[0063] By adjusting the density gradient of the lattice (left side), the software can automatically generate the macroscopic pore structure (right side) with the required gradient.

[0064] The density gradient of the dot matrix is ​​generated by randomly removing points based on distance. That is, a certain number of uniformly distributed dots are first generated, and then a removal operation is performed. Points closer to the center of the model have a greater chance of being removed, thus generating a dot matrix with a density gradient.

[0065] Let the probability of each point in the matrix being removed be referred to the following formula (1):

[0066] (1)

[0067] in, Let be the distance of the point relative to the reference plane (zero point). Assuming that the number of points is sufficiently large, the distribution function of the lattice density is given by equation (2) below:

[0068] (2)

[0069] in, The distance of the highest point in the generated dot matrix region relative to the reference plane (zero point);

[0070] If the total number of points generated in the specified matrix is Then when When the value is sufficiently large, the lattice density distribution function can be discretized; the lattice can be considered as a probability density function as shown in equation (3) below:

[0071] (3)

[0072] In this example, we take the reference plane (zero point) as a surface that generates the volume center of the region through a lattice, the lattice density is symmetrical on both sides of the reference plane, and we take:

[0073] (4)

[0074] in, The distance from the selected cross-section to the reference plane (zero point). The height of the lattice generation region is given by equation (5).

[0075] (5)

[0076] If N points are generated during actual modeling, this continuous distribution can be discretized; the point matrix can be symmetrically divided into n equidistant intervals along the Z-axis.

[0077] See appendix Figure 5 (a) To clearly illustrate each part, only a portion of the intervals are shown in the diagram; in the subsequent statistics on the number of points, the sum of the symmetrical regions on both sides of the reference plane is calculated; then, in the k-th interval, the expected value of the number of points remaining after the elimination process is... It should be:

[0078] (6)

[0079] In this example, we take N=500, H=50mm, and the expected value is... For a comparison with the actual number of generated points, please refer to the appendix. Figure 5 (b) In the chart, we take n=10 in the statistics and calculations. As shown in the figure, the theoretical prediction value and the actual number generated by the program are almost the same.

[0080] Step 4: Design the mesoscopic and microscopic pore structure of the iron-based metal-glass biomimetic leg bone artificial bone implant;

[0081] Depending on the control software of the laser powder bed fusion additive manufacturing system, the design method will also be different. In this embodiment, the original artificial bone implant model will be divided into mesoscopic and microscopic pore regions by segmentation and reassembly.

[0082] See appendix Figure 7 The original artificial bone implant model was divided into three sub-regions. The three sub-regions were stained with different gray values ​​in the figure. From left to right, they are the original artificial bone implant model, outer layer, middle layer and inner layer.

[0083] Next, different process parameters are applied to each sub-region, and the final artificial bone implant will have a continuous macroscopic pore structure and a three-level transitional mesomicroscopic gradient pore structure.

[0084] Step 5: Import the model into Ansys for finite element simulation analysis. If the strength meets the clinical requirements, the current design will be used. If the strength does not meet the clinical requirements, return to Step 1 to redesign the pore structure distribution of the bionic artificial bone implant.

[0085] Step 6: Input the three-dimensional model files of the three sub-regions into the laser powder bed melting additive manufacturing system slicing software in STL format, and complete the reassembly. Set the layer thickness to 30 μm and the scanning interval to 70 μm.

[0086] Based on the design of the mesoscopic and microscopic pore structures, different laser powers and scanning speeds were set for the three different sub-regions of the reassembled model;

[0087] The software slices the model file according to the parameter settings, calculates the scanning path, and converts the three-dimensional data of the model into code that controls the deflection of the galvanometer and the power of the laser. In the subsequent printing, the mesoscopic and microscopic pore structure of the artificial bone implant will be determined by the process parameters.

[0088] In this embodiment, the laser power for the mesoporous structure in the inner layer region is 50 W, and the scanning speed is 200 mm / s; the laser power for the mesoporous structure in the middle layer region is 120 W, and the scanning speed is 500 mm / s; the laser power for the microporous structure in the outer layer region is 190 W, and the scanning speed is 1300 mm / s.

[0089] Step 7: Place the prepared Fe-based metal glass powder into the powder supply cylinder in the forming chamber, and then operate the control software of the laser powder bed melting additive manufacturing system to introduce high-purity argon into the working chamber for deoxygenation. When the oxygen content reaches the permissible value, operate the control software to perform the printing operation.

[0090] Step 8: The laser powder bed fusion additive manufacturing system will adjust the galvanometer angle and laser power according to the layer contour information obtained from the slicing process and the set process parameters, and melt the metal glass powder laid in the forming cylinder at a certain power and scanning speed to form the metal glass bionic artificial bone implant.

[0091] Step 9: After the current layer of metal powder solidifies, the forming cylinder descends by one layer thickness, the powder supply cylinder descends by one layer thickness, and the next layer of metal glass powder is laid through the powder spreading system. The software then melts the next layer according to the layer contour information and process parameters. This process is repeated layer by layer until a complete iron-based metal glass bionic leg bone artificial bone implant is finally formed; see the appendix for the morphology of the formed part. Figure 2 For the postoperative morphology of the bionic leg bone artificial bone implanted into the defective leg bone, please refer to the appendix. Figure 8 .

[0092] Step 10: Use a universal testing machine and a three-point bending testing machine to test the compression, torsion and bending properties of the formed metal-glass bionic artificial bone implant;

[0093] If the mechanical properties meet clinical requirements, the current printed part can be used directly as needed, or the implant can be reprinted according to the aforementioned designed geometric parameters and macroscopic and microscopic porosity parameters.

[0094] If the mechanical properties do not meet clinical requirements, it is necessary to return to step 1 to redesign the pore structure distribution of the bionic artificial bone implant before printing the next batch of metal-glass bionic artificial bone implants.

[0095] Example 2:

[0096] In addition to the macroscopic pore structure schemes described above, depending on the specific application scenario, stochastic gradient pore structure schemes based on pore size gradients can also be adopted in the design. See Appendix. Figure 3 ;

[0097] In this scheme, the pore distribution and model effect are shown in the appendix. Figure 6 The lattice on the left side of the figure represents the pore size and density distribution of the implant; by adjusting the pore size and pore density distribution functions, a corresponding gradient pore structure is generated.

[0098] In summary, the macroscopic pore structure of the artificial bone implant in this invention is determined through a model file.

[0099] In summary, this invention designs from both three-dimensional model and process parameter perspectives, achieving control over the internal pore structure of parts at the macroscopic, mesoscopic, and microscopic levels. It can completely reproduce the precise gradient pore structure inside cortical bone and cancellous bone. Simultaneously, by controlling the porosity, the elastic modulus of the printed artificial bone implant can be subjectively adjusted, effectively mitigating the stress shielding effect. Furthermore, with the enhanced control over the elastic modulus of the implant, higher-strength materials can be introduced to replace traditional titanium alloys, improving the strength and stability of the biomimetic artificial bone implant. Therefore, high-performance materials that were previously unusable in clinical applications can be put into practical use.

[0100] Example 3:

[0101] The macroscopic pores can be constructed using a homogenization method based on lattice units to create an ordered and periodic lattice structure. By adjusting the pore size distribution of the lattice units, a gradient pore structure can be achieved. Alternatively, a random pore structure without order or periodicity can be generated based on a three-dimensional spatial lattice using a Voronoi diagram. Then, the gradient pore structure can be achieved by adjusting the density distribution of the three-dimensional spatial lattice.

[0102] Example 4:

[0103] The modeling of the bionic artificial bone implant described in step 3 can be done using other 3D modeling software such as Catia, Solidworks, and Blender.

[0104] Example 6:

[0105] The adjustable ranges of the parameters mentioned in step 6 are as follows: the laser power is adjustable from 0 to 500 W, the scanning speed is adjustable from 0 to 1600 mm / s, the layer thickness is adjustable from 30 to 40 μm, and the scanning spacing is adjustable from 70 to 110 μm.

[0106] The porosity of parts formed by laser powder bed melting technology can be controlled by adjusting the laser power and scanning speed. However, since the mechanism of pore generation is different in different parameter ranges, the corresponding pore sizes are also very different. Therefore, the intrinsic pores induced by adjusting the process parameters can be divided into two types: mesoscopic (100-500 μm) and microscopic (<100 μm).

[0107] By appropriately adjusting the laser power and scanning speed, pore structures ranging from tens to hundreds of micrometers can be generated as needed. By setting gradient process parameters between different layers or scanning channels using software, mesoscopic and microscopic gradient pore structures can be integrally formed. Furthermore, even finer microscopic pore structure control can be achieved by performing secondary laser scanning on selected areas.

[0108] Example 7:

[0109] The metallic glass powder mentioned in step 1 can be one or more of Pd-based, Fe-based, Zr-based, Mg-based, Al-based, Ti-based, Cu-based, Ce-based, and La-based metallic glasses, depending on actual clinical needs.

Claims

1. A method for laser powder bed fusion additive manufacturing of metallic glass biomimetic artificial bone implants, characterized in that, include: S1. Pre-formed metallic glass powder with a particle size of 30-50μm; S2. Determine the geometry of the metal-glass biomimetic artificial bone implant according to clinical and mechanical performance requirements, and design the pore structure distribution based on the three levels of macroscopic, mesoscopic, and microscopic. The macroscopic scale is >500μm, the mesoscopic scale is 100-500μm, and the microscopic scale is <100μm. S3. Use 3D modeling software to create a 3D model of the metal-glass bionic artificial bone implant; The macroscopic pore structure of the implant adopts a random gradient pore structure based on a density-adjustable three-dimensional spatial lattice; by adjusting the density gradient of the lattice, a macroscopic pore structure with the required gradient is generated. The density gradient of the dot matrix is ​​generated by randomly removing points based on distance; First, a certain number of uniformly distributed points are generated. Points closer to the center of the model have a higher probability of being removed, thus generating a point matrix with a density gradient. S4. The mesoscopic and microscopic pore structure of the artificial bone implant was determined by dividing and reassembling the original artificial bone implant model into three sub-regions: outer layer, middle layer, and inner layer. S5. Import the model into Ansys for finite element simulation analysis. If the strength meets the clinical requirements, the current design will be used. If the strength does not meet the clinical requirements, return to step 1 to redesign the pore structure distribution of the artificial bone implant. S6. Input the 3D model files of the three sub-regions into the laser powder bed fusion additive manufacturing system slicing software in STL format and then assemble them, setting the layer thickness and scanning interval; and convert the 3D data of the model into code to control the galvanometer deflection and laser power, thereby determining the laser power and scanning speed parameters; Perform laser scanning on the three sub-regions; S7. Place the pre-made metal glass powder into the powder supply cylinder in the forming chamber, introduce high-purity argon into the working chamber to perform deoxygenation, and when the oxygen content reaches the permissible value, form the metal glass powder of the metal glass bionic artificial bone implant layer by layer. S8. The compression, torsion and bending properties of the formed metal-glass bionic artificial bone implant were tested using a universal testing machine and a three-point bending testing machine. If the mechanical properties meet clinical requirements, they can be formed according to the aforementioned geometric parameters and pore size. If the mechanical properties do not meet clinical requirements, return to step 1 to redesign the pore structure distribution of the biomimetic artificial bone implant.

2. The laser powder bed fusion additive manufacturing method for metallic glass biomimetic artificial bone implants according to claim 1, characterized in that: S3 describes the generation of a lattice with a density gradient: Let the probability of each point in the dot matrix being removed be: （1） in, Let be the distance of this point relative to the reference plane. Assuming there are a sufficiently large number of points, the distribution function of the lattice density is: （2） in, The distance of the highest point in the generated dot matrix region relative to the reference plane; If the total number of points generated in the specified matrix is ,when When the value is sufficiently large, the lattice density distribution function is discretized; the lattice can be considered as having a probability density function as follows: （3）。 3. The laser powder bed fusion additive manufacturing method for metallic glass biomimetic artificial bone implants according to claim 2, characterized in that: The reference plane can be taken as the surface through which the volume center of the region is generated by the lattice, the lattice density is symmetrical on both sides of the reference plane, and the following values ​​are taken: （4） in, The distance from the selected cross section to the reference plane. Let the height be the region where the lattice is generated, and the distribution function of the lattice density is: （5） If N points are generated during actual modeling, this continuous distribution can be discretized; the point matrix can be symmetrically divided into n equidistant intervals along the Z-axis. When counting the number of points, the sum of the symmetrical regions on both sides of the reference plane is calculated; then, the expected value of the number of points remaining after the elimination process in the k-th interval is... It should be: （6）。 4. The laser powder bed fusion additive manufacturing method for metallic glass biomimetic artificial bone implants according to claim 3, characterized in that: The macroscopic pore structure adopts a stochastic gradient pore structure scheme based on pore size gradient; by adjusting the pore size and pore density distribution function, the corresponding gradient pore structure is generated.

5. The laser powder bed fusion additive manufacturing method for metallic glass biomimetic artificial bone implants according to claim 3, characterized in that: The macroscopic pore structure is constructed using a homogenization method based on lattice units to create an ordered and periodic lattice structure. By adjusting the pore size distribution of the lattice units, a corresponding gradient pore structure is generated. Alternatively, based on a three-dimensional spatial lattice, a gradient pore structure can be generated by using a random pore structure that lacks order and periodicity, and by adjusting the density distribution of the three-dimensional spatial lattice.

6. The laser powder bed fusion additive manufacturing method for metallic glass biomimetic artificial bone implants according to claim 4 or 5, characterized in that: The modeling of the bionic artificial bone implant described in S1 was completed using three-dimensional modeling software such as Catia, Solidworks, Blender, or Rhino.

7. The laser powder bed fusion additive manufacturing method for metallic glass biomimetic artificial bone implants according to claim 6, characterized in that: The adjustable range of each parameter described in S6 is as follows: The laser power is adjustable from 0 to 500 W, the scanning speed is adjustable from 0 to 1600 mm / s, the layer thickness is adjustable from 30 to 40 μm, and the scanning spacing is adjustable from 70 to 110 μm.

8. The laser powder bed fusion additive manufacturing method for metallic glass biomimetic artificial bone implants according to claim 7, characterized in that: The three sub-regions were laser scanned twice.

9. The laser powder bed fusion additive manufacturing method for metallic glass biomimetic artificial bone implants according to claim 8, characterized in that: The metallic glass powder is a Pd-based, Fe-based, Zr-based, Mg-based, Al-based, Ti-based, Cu-based, Ce-based, and / or La-based metallic glass.

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