Bone material suitable for additive manufacturing and preparation method thereof

Abstract

The invention discloses a skeleton material suitable for additive manufacturing and a preparation method thereof.The method comprises the following steps that S1, CNTs are added into ethyl alcohol, stirring and ultrasonic dispersion are conducted, and CNTs ethyl alcohol dispersion liquid is obtained; s2, PEEK powder is added into the CNTs ethanol dispersion liquid, stirring and ultrasonic dispersion are carried out, and a CNTs-PEEK-ethanol blending liquid is obtained; s3, stirring the CNTs-PEEK-ethanol blended solution until the weight of the CNTs-PEEK-ethanol blended solution is not reduced any more, so as to obtain CNTs-PEEK powder; s4, after the CNTs-PEEK powder is dried, the CNTs-PEEK powder is extruded, and a CNTs-PEEK wire is obtained; s5, after the CNTs-PEEK wire is dried again, the CNTs-PEEK wire is subjected to high-temperature melting extrusion printing, and the personalized skeleton scaffold is obtained; the invention provides a bone material which is suitable for additive manufacturing, good in mechanical property and not prone to brittle fracture and a preparation method of the bone material.

Description

Technical Field

[0001] This invention relates to the field of orthopedic materials technology, specifically a bone material suitable for additive manufacturing and its preparation method. Background Technology

[0002] Additive manufacturing, commonly known as 3D printing, is a manufacturing technology that integrates computer-aided design, materials processing and forming technologies. Based on digital model files, it uses software and CNC systems to layer specialized metallic, non-metallic, and medical / biomaterials through methods such as extrusion, sintering, melting, photopolymerization, and spraying to create physical objects. Unlike traditional processing methods that involve removing raw materials, cutting, and assembling, it is a bottom-up manufacturing method that adds materials from scratch. This makes it possible to manufacture complex structural components that were previously impossible due to the constraints of traditional manufacturing methods.

[0003] Polyetheretherketone (PEEK) is a semi-crystalline polymer with excellent chemical resistance, X-ray transparency, and an elastic modulus similar to human bone. It is increasingly being used as an implantable biomaterial in orthopedics and oral and maxillofacial surgery. More importantly, PEEK can be processed using additive manufacturing, allowing for customized implants tailored to individual patient needs.

[0004] Compared to metals, especially titanium or its alloys, PEEK still suffers from insufficient mechanical properties and poor osseointegration for load-bearing joints or bones. To further improve the mechanical strength of PEEK, many studies have added materials such as carbon fibers, carbon nanofibers, glass fibers, and carbon nanotubes (CNTs) to prepare mechanically reinforced PEEK composites using solution or melt blending methods. There is considerable research on the reactive modification of PEEK, mainly focusing on blending PEEK with bioactive substances and surface-active modification. The former involves blending PEEK with HA, Bio-Glass, TiO2, or Ti to prepare bioactive PEEK composites; the latter involves physical treatments (including spraying, surface roughening, and porous structures), deposition techniques (including TCP and HA deposition), and chemical techniques (including BMP-2 grafting). However, these processes are complex and have a single objective. The main scientific challenge lies in developing novel PEEK materials for use in load-bearing bones and joints, while also satisfying mechanical and osseointegration requirements.

[0005] CNTs, an isotopic variant of crystalline carbon, possess excellent mechanical properties, high toughness, thermal stability, and bioactivity. They can improve upon the shortcomings of PEEK, such as insufficient mechanical properties, poor bioactivity, poor heat resistance, and poor friction. Furthermore, the nanostructure of CNTs, when used as a filler within a certain dosage range, does not affect the processing performance of PEEK. These factors make CNTs one of the most promising reinforcing materials for improving PEEK properties. Currently, most research on composite CNTs and PEEK utilizes physical methods such as solution or melt blending, followed by the preparation of CNTs-PEEK physical blends using injection molding, compression molding, or 3D printing technologies. However, the improvement in mechanical strength is only minimal.

[0006] In summary, the existing technology still lacks a bone material and method that is suitable for additive manufacturing, has good mechanical properties, and is not prone to brittle fracture. Summary of the Invention

[0007] This invention overcomes these difficulties and provides a bone material suitable for additive manufacturing, with good mechanical properties and not prone to brittle fracture, as well as a method for preparing the same.

[0008] To achieve this objective, the present invention provides the following technical solution:

[0009] In a first aspect, the present invention provides a method for preparing a bone material suitable for additive manufacturing, comprising the following steps:

[0010] S1. Add CNTs to ethanol, stir, and ultrasonically disperse to obtain CNTs ethanol dispersion;

[0011] S2. Add PEEK powder to CNTs ethanol dispersion, stir, and ultrasonically disperse to obtain CNTs-PEEK-ethanol blend;

[0012] S3. Stir the CNTs-PEEK-ethanol mixture until the weight no longer decreases to obtain CNTs-PEEK powder.

[0013] S4. After drying the CNTs-PEEK powder, extrude it to obtain CNTs-PEEK wire;

[0014] S5. After drying the CNTs-PEEK filaments again, high-temperature melting and extrusion printing is used to obtain a personalized skeletal scaffold.

[0015] Preferably, in steps S1 and S2, the ultrasonic dispersion power is 100-150W and the time is 30-50min.

[0016] In this invention, in step S2, CNTs-PEEK-ethanol blend is obtained by ultrasonic dispersion. Compared with other methods, ultrasonic treatment of CNTs-PEEK composite material enhances both its bending and tensile properties.

[0017] Preferably, in steps S1 and S2, the stirring rate is 500-800 rpm and the stirring time is 5-10 min.

[0018] Preferably, in steps S4 and S5, the drying temperature is 100°C and the drying time is not less than 4 hours.

[0019] Preferably, the mass percentage of CNTs in CNTs-PEEK wire is no more than 20%; more preferably, the mass percentage of CNTs in CNTs-PEEK wire is 5%-15%.

[0020] In this invention, the tensile strength and tensile modulus of CNTs-PEEK wire gradually increase with increasing CNT content, while the tensile elongation at break decreases with increasing CNT content. 15% and 20% CNTs-PEEK wires exhibit more significant brittle fracture characteristics. Therefore, in the bone material of this invention, the mass percentage of CNTs is no more than 20%.

[0021] Preferably, in step S4: after drying the CNTs-PEEK powder, an extruder is used to extrude the nozzle with a diameter of 2.0 mm, and the nozzle temperature and cavity temperature are set to 380-400℃, with the nozzle temperature being 10℃ higher than the cavity temperature, to prepare the CNTs-PEEK filament required for printing.

[0022] Preferably, in step S5: after drying the CNTs-PEEK filament, high-temperature melt extrusion printing is used, with a nozzle temperature of 380-400℃, a platform temperature of 160-180℃, a cavity temperature of 80-100℃, a printing speed of 10-15mm / s, and a nozzle diameter of 0.4-0.6mm, to prepare the bone material required for clinical use.

[0023] Preferably, a method for preparing a bone material suitable for additive manufacturing includes the following steps:

[0024] 1) Add CNTs to ethanol, stir at 500 rpm for 10 min, and then treat with an ultrasonic disperser at 150 W for 30 min to obtain CNTs ethanol dispersion.

[0025] 2) Add PEEK powder to CNTs ethanol dispersion, stir at 500 rpm for 10 min, and then treat with an ultrasonic disperser at 150 W power for 30 min to obtain CNTs-PEEK-ethanol blend.

[0026] 3) Stir the CNTs-PEEK-ethanol mixture at 500 rpm and 100°C until the weight no longer decreases to obtain CNTs-PEEK powder;

[0027] 4) After drying the obtained CNTs-PEEK powder at 100℃ for 4 hours, use a single-shaft or dual-shaft extruder with an extrusion nozzle diameter of 2.0 mm, and set the nozzle temperature and chamber temperature to 390-400℃ and 380-400℃ respectively to obtain CNTs-PEEK wire.

[0028] 5) After drying the CNTs-PEEK filament at 100℃ for 4 hours, high-temperature melt extrusion printing is used. The nozzle temperature is 380-400℃, the platform temperature is 160-180℃, the cavity temperature is 80-100℃, the printing speed is 10-15mm / s, and the nozzle diameter is 0.4-0.6mm to prepare the plant instruments required for clinical use.

[0029] Preferably, the CNTs-PEEK powder is filtered twice through 400μm, 200μm and 100μm sieves before drying to balance the powder size.

[0030] Preferably, a 5-10% polyvinylpyrrolidone (PVP) aqueous solution should be evenly applied to the printing platform before high-temperature melt extrusion printing to prevent the CNTs-PEEK sample from curling up during cooling.

[0031] Preferably, after the CNTs-PEEK sample is printed, it should be allowed to cool naturally from the cavity temperature of 80-100℃ to room temperature before being removed.

[0032] A second aspect of the invention provides a bone material suitable for additive manufacturing prepared by the method described herein.

[0033] Preferably, the tensile strength and modulus of the material are 99-131 MPa and 2.7-3.6 GPa, respectively.

[0034] Preferably, the mass percentage of CNTs in the material is no more than 20%; more preferably, the mass percentage of CNTs in the material is 5%-15%.

[0035] In summary, this invention first utilizes ultrasonic treatment to obtain uniformly mixed CNTs-PEEK powder; secondly, it obtains uniformly mixed CNTs-PEEK filaments again through high-temperature melting; finally, by controlling parameters such as 3D printing temperature, layer thickness, and speed, it prepares CNTs-PEEK samples with high mechanical properties and bioactivity. The bone material prepared by this invention can be used in additive manufacturing, exhibits good mechanical properties, and is not prone to brittle fracture.

[0036] Compared with the prior art, the beneficial effects and significant progress of the present invention are as follows: The present invention prepares bone materials with high mechanical properties and bioactivity by ultrasonic mixing, melt blending and printing parameter control, which improves the clinical problems such as insufficient mechanical properties and bioinertness of PEEK and expands its clinical application scope. Attached Figure Description

[0037] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly introduced below.

[0038] Obviously, the accompanying drawings described below are only some of the drawings of the embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort, but these other drawings are also within the scope of the drawings required for the embodiments of the present invention.

[0039] Figure 1 This is a SEM image of the material prepared in Example 1 of the present invention;

[0040] Figure 2 This is a representative tensile stress-strain curve of Embodiment 2 of the present invention;

[0041] Figure 3 The figure shows the tensile strength and tensile modulus results of Embodiment 2 of the present invention;

[0042] Figure 4 This is a graph showing the tensile elongation at break results of Embodiment 2 of the present invention;

[0043] Figure 5 This is a typical stress-strain curve from the bending test of Embodiment 2 of the present invention;

[0044] Figure 6 The graph shows the bending strength and bending modulus results of Embodiment 2 of the present invention;

[0045] Figure 7 This is a diagram showing the brittle fracture results of Comparative Example 2 of the present invention;

[0046] Figure 8 A flowchart illustrating the preparation of clinically required bone materials from the CNTs-PEEK filaments of Embodiment 3 of the present invention;

[0047] Figure 9 This is a diagram showing the results of Micro-CT detection of the internal porosity of a 3D-printed sample in Example 3 of the present invention.

[0048] Figure 10 This is a SEM image of the material prepared in Comparative Example 1 of this invention;

[0049] Figure 11The figure shows the tensile properties of the material prepared in Comparative Example 1 of this invention.

[0050] Figure 12 The graph shows the bending performance of the material prepared in Comparative Example 1 of this invention. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the present invention is further described below in conjunction with specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or as recommended by the manufacturer. Unless otherwise stated, percentages and parts are weight percentages and parts by weight. Unless otherwise specified, the experimental materials and reagents used in the following embodiments are commercially available.

[0052] Unless otherwise specified, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should be noted that the terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the exemplary embodiments of this application.

[0053] It should be noted that the terms "first," "second," and "third" (if present), etc., in the specification, claims, and accompanying drawings of the embodiments of this invention, are only used to distinguish different objects and not to describe a specific order. Furthermore, the term "comprising" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0054] The technical solution of the present invention will now be described in detail with reference to specific embodiments.

[0055] Example 1: Preparation of CNTs-PEEK Composite Material

[0056] Composite materials for different experimental groups were prepared according to the following method. The only difference between the experimental groups was the mass ratio of CNTs in the CNTs-PEEK group. Specifically, the mass of CNTs in the PEEK group was 0; in the 5% CNTs-PEEK group, the mass of CNTs was 5%; in the 10% CNTs-PEEK group, the mass of CNTs was 10%; in the 15% CNTs-PEEK group, the mass of CNTs was 15%; and in the 20% CNTs-PEEK group, the mass of CNTs was 20%.

[0057] The preparation method of CNTs-PEEK composite material is as follows:

[0058] 1.1 Add CNTs to ethanol, stir at 500 rpm for 10 min, and then treat with an ultrasonic disperser at 150 W for 30 min to obtain CNTs ethanol dispersion;

[0059] 1.2 Add PEEK powder to CNTs ethanol dispersion, stir at 500 rpm for 10 min, and then treat with an ultrasonic disperser at 150 W power for 30 min to obtain CNTs-PEEK-ethanol blend.

[0060] 1.3. Stir the CNTs-PEEK-ethanol blend at 500 rpm and 100°C until the weight no longer decreases to obtain CNTs-PEEK powder.

[0061] 1.4 After drying the obtained CNTs-PEEK powder at 100℃ for 4 hours, use a single-shaft or dual-shaft extruder with an extrusion nozzle diameter of 2.0 mm, and set the nozzle temperature and chamber temperature to 390℃ and 380℃ respectively to obtain CNTs-PEEK wire.

[0062] The five groups of composite materials were observed using SEM.

[0063] SEM observation results are as follows: Figure 1 As shown, it can be seen that with the increase of CNTs content, the color of CNTs-PEEK powder becomes darker, and more CNTs adhere to the PEEK surface.

[0064] Example 2 Performance Testing

[0065] Tensile properties

[0066] Tensile properties of the five composite materials prepared in Example 1 were tested, and the method for testing tensile properties was in accordance with the standard ASTM-D638.

[0067] result Figure 2-4 As shown. Among them, Figure 2 It is a representative tensile stress-strain curve.

[0068] Figure 3 The graph shows the results for tensile strength and tensile modulus, which also gradually increase with increasing CNT content. The average tensile strength and modulus of pure PEEK are 93.0 MPa and 2.4 GPa, respectively; 5% CNTs-PEEK reaches 99.2 MPa and 2.7 GPa, respectively; 10% CNTs-PEEK increases to 112.7 MPa and 2.9 GPa; 15% CNTs-PEEK reaches 122.8 MPa and 3.0 GPa; and 20% CNTs-PEEK significantly increases to 131.5 MPa and 3.6 GPa.

[0069] Figure 4 The graph shows the tensile elongation at break. It can be seen that the elongation at break decreases with the increase of CNTs addition. Pure PEEK is 59.7%, while 5%, 10%, 15%, and 20% CNTs-PEEK decrease to 13.1%, 11.8%, 9.8%, and 6.6%, respectively.

[0070] Bending performance

[0071] The bending properties of the five composite materials prepared in Example 1 were tested, and the method for testing the bending properties was in accordance with the standard ASTM-D790.

[0072] The results are as follows Figure 5-7 As shown, where, Figure 5 Typical stress-strain curves from bending tests are shown.

[0073] Figure 6 The graph shows the results of flexural strength and flexural modulus. It can be seen that the flexural strength and flexural modulus gradually increase with the increase of CNT content.

[0074] Figure 7 The image shows the brittle fracture results. It can be seen that 15% and 20% CNTs-PEEK exhibit more significant brittle fracture characteristics.

[0075] Example 3 Printing Performance Testing

[0076] This embodiment demonstrates the preparation of CNTs-PEEK wires from Example 1 into a clinically required bone material.

[0077] The process is as follows Figure 8 As shown, after drying at 100℃ for 4 hours, high-temperature melt extrusion printing was used, with nozzle temperature of 380-400℃, platform temperature of 160-180℃, cavity temperature of 80-100℃, printing speed of 10-15mm / s, and nozzle diameter of 0.4-0.6mm, to prepare the plant instruments required for clinical use.

[0078] Test samples were printed using a high-temperature FDM printer. A 5-10% polyvinylpyrrolidone (PVP) aqueous solution was evenly applied to the printing platform to prevent edge warping of the CNTs-PEEK samples during cooling. The nozzle temperature was set to 380℃, the platform temperature to 160℃, and the chamber temperature to 80℃. The printing speed was 15mm / s, and the nozzle diameter was 0.6mm. After printing, the CNTs-PEEK samples were allowed to cool naturally from the chamber temperature of 80-100℃ to room temperature before being removed.

[0079] result Figure 9As shown, the porosity of the CNTs-PEEK sample prepared by the method of this invention is controlled within 1% when the internal porosity of the 3D printed sample is detected by Micro-CT.

[0080] Comparative Example 1

[0081] The three sets of materials in this comparative example were prepared according to the method in Example 1. The preparation methods of the three sets of composite materials in this comparative example are as follows:

[0082] 4.1 Add CNTs to ethanol, stir at 500 rpm for 10 min, and then treat with an ultrasonic disperser at 150 W for 30 min to obtain CNTs ethanol dispersion;

[0083] 4.2 Add PEEK powder to CNTs ethanol dispersion, stir at 500 rpm for 10 min, and then treat with an ultrasonic disperser at 150 W power for 30 min to obtain CNTs-PEEK-ethanol blend.

[0084] 4.3. Stir the CNTs-PEEK-ethanol blend at 500 rpm and 100°C until the weight no longer decreases to obtain CNTs-PEEK powder.

[0085] 4.4 After drying the obtained CNTs-PEEK powder at 100℃ for 4 hours, use a single-shaft or dual-shaft extruder with an extrusion nozzle diameter of 2.0 mm and the nozzle temperature and chamber temperature set to 400℃ and 400℃ respectively to obtain CNTs-PEEK wire.

[0086] The only difference is:

[0087] Group G1 is PEEK, and no CNTs are added;

[0088] In step 4.2 of group G2, PEEK powder is added to the CNTs ethanol dispersion and stirred at 500 rpm for 60 min to obtain a CNTs-PEEK-ethanol blend.

[0089] In step 4.2 of group G3, PEEK powder is added to the CNTs ethanol dispersion, stirred at 500 rpm for 10 min, and then treated with an ultrasonic disperser at 150 W power for 30 min to obtain a CNTs-PEEK-ethanol blend.

[0090] SEM observation

[0091] The results are as follows Figure 10As shown, in group G1, PEEK particles showed no agglomeration, with an average agglomerated particle size of 80 μm; in group G2, which was a manually mixed powder group, CNTs and PEEK particles existed separately, with few or no CNTs visible on the PEEK surface; in group G3, which was an ultrasonically treated group, the agglomerated CNT particles became smaller, and many small agglomerated CNT particles and single CNTs were visible on the PEEK surface. This indicates that ultrasonic treatment makes CNTs more uniformly dispersed in PEEK, which is the main factor enhancing its mechanical properties.

[0092] Tensile properties

[0093] The method is the same as in Example 2.

[0094] The results are as follows Figure 11 As shown, the tensile strength of the pure PEEK group (G1) is 93.0 MPa, the tensile strength of the manually mixed powder group (G2) is 102.5 MPa, and the tensile strength of the ultrasonically treated CNTs-PEEK group (G3) is 112.7 MPa. The tensile modulus of elasticity is 2.4 GPa for group G1, 2.7 GPa for group G2, and 2.9 GPa for group G3. In terms of tensile strength, the ultrasonically treated CNTs-PEEK composite material shows a greater increase; in terms of elastic modulus, the ultrasonically treated CNTs-PEEK composite material also shows a significant increase in elastic modulus.

[0095] Bending performance

[0096] The method is the same as in Example 2.

[0097] The results are as follows Figure 12 As shown, the flexural strength was 118.20 MPa in group G1, 132.9 MPa in group G2, and 152.7 MPa in group G3. The flexural modulus was 2.4 GPa in group G1, 2.9 GPa in group G2, and 3.7 GPa in group G3. Analysis of the above data shows that the tensile strength of the ultrasonically treated CNTs-PEEK composite material was significantly improved; the elastic modulus also indicates that the ultrasonically treated CNTs-PEEK composite material has a higher value.

[0098] In the description process of the above instruction manual:

[0099] The terms "this embodiment," "an embodiment of the present invention," "as shown," "further," and "further improved technical solutions," etc., indicate that the specific features, structures, materials, or characteristics described in the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms are not necessarily directed at the same embodiment or example, and the specific features, structures, materials, or characteristics described can be combined or combined in any suitable manner in one or more embodiments or examples. Furthermore, without causing contradiction, those skilled in the art can combine or combine the different embodiments or examples described in this specification and the features of the different embodiments or examples.

[0100] Finally, it should be noted that:

[0101] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them;

[0102] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention. Non-essential improvements, adjustments or substitutions made by those skilled in the art based on the content of this specification are all within the scope of protection claimed by the present invention.

Claims

1. A method for preparing a bone material suitable for additive manufacturing, characterized in that, Includes the following steps: S1. Add CNTs to ethanol, stir, and ultrasonically disperse to obtain CNTs ethanol dispersion; S2. Add PEEK powder to CNTs ethanol dispersion, stir, and ultrasonically disperse to obtain CNTs-PEEK-ethanol blend; S3. Stir the CNTs-PEEK-ethanol mixture until the weight no longer decreases to obtain CNTs-PEEK powder. S4. After drying the CNTs-PEEK powder, extrude it to obtain CNTs-PEEK wire; S5. After drying the CNTs-PEEK filaments again, use high-temperature melting and extrusion printing to obtain the skeletal scaffold.

2. The method for preparing a bone material suitable for additive manufacturing as described in claim 1, characterized in that, In steps S1 and S2, the ultrasonic dispersion power is 100-150W, and the time is 30-50min.

3. The method for preparing a bone material suitable for additive manufacturing as described in claim 1, characterized in that, In steps S1 and S2, the stirring speed is 500-800 rpm and the stirring time is 5-10 min.

4. The method for preparing a bone material suitable for additive manufacturing as described in claim 1, characterized in that, In steps S4 and S5, the drying temperature is 100℃ and the time is no less than 4 hours.

5. The method for preparing a bone material suitable for additive manufacturing as described in claim 1, characterized in that, In CNTs-PEEK wires, the CNTs content is no more than 20% of the total mass.

6. The method for preparing a bone material suitable for additive manufacturing as described in claim 5, characterized in that, In CNTs-PEEK wires, CNTs account for 5%-15% of the total mass.

7. The method for preparing a bone material suitable for additive manufacturing as described in claim 1, characterized in that, In step S4: After drying the CNTs-PEEK powder, use an extruder with a nozzle diameter of 2.0 mm, and set the nozzle temperature and chamber temperature to 380-400℃, with the nozzle temperature being 10℃ higher than the chamber temperature, to prepare the CNTs-PEEK filament required for printing.

8. The method for preparing a bone material suitable for additive manufacturing as described in claim 1, characterized in that, In step S5: After drying the CNTs-PEEK filament, high-temperature melt extrusion printing is used, with a nozzle temperature of 380-400℃, a platform temperature of 160-180℃, a cavity temperature of 80-100℃, a printing speed of 10-15mm / s, and a nozzle diameter of 0.4-0.6mm.

9. A bone material suitable for additive manufacturing prepared by the method according to any one of claims 1-8.

10. The bone material suitable for additive manufacturing as described in claim 9, characterized in that, The tensile strength and modulus of the material are 99-131 MPa and 2.7-3.6 GPa, respectively.

11. The bone material suitable for additive manufacturing as described in claim 9, characterized in that, In the material, the mass percentage of CNTs is no more than 20%.

12. The bone material suitable for additive manufacturing as described in claim 11, characterized in that, In the material, CNTs account for 5%-15% by mass.

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