CN112296355A - Method for manufacturing titanium alloy bone tissue engineering implant with micron-sized topological porous structure by SLM (Selective laser melting) - Google Patents

Method for manufacturing titanium alloy bone tissue engineering implant with micron-sized topological porous structure by SLM (Selective laser melting) Download PDF

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CN112296355A
CN112296355A CN202011028948.XA CN202011028948A CN112296355A CN 112296355 A CN112296355 A CN 112296355A CN 202011028948 A CN202011028948 A CN 202011028948A CN 112296355 A CN112296355 A CN 112296355A
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bone tissue
tissue engineering
micron
titanium alloy
laser
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CN112296355B (en
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周长春
易涛
范洪远
雷皓远
钱熙文
王科锋
蒋青
樊渝江
张兴栋
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Sichuan University
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Sichuan University
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/10—Sintering only
    • B22F3/11—Making porous workpieces or articles
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
    • A61L27/02—Inorganic materials
    • A61L27/04—Metals or alloys
    • A61L27/06—Titanium or titanium alloys
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
    • A61L27/50—Materials characterised by their function or physical properties, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
    • A61L27/56—Porous materials, e.g. foams or sponges
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
    • B22F5/10—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product of articles with cavities or holes, not otherwise provided for in the preceding subgroups
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y10/00—Processes of additive manufacturing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y50/00—Data acquisition or data processing for additive manufacturing
    • B33Y50/02—Data acquisition or data processing for additive manufacturing for controlling or regulating additive manufacturing processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y80/00—Products made by additive manufacturing
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L2430/00—Materials or treatment for tissue regeneration
    • A61L2430/02—Materials or treatment for tissue regeneration for reconstruction of bones; weight-bearing implants

Abstract

The invention discloses a method for manufacturing a titanium alloy bone tissue engineering implant with a micron-sized topological porous structure by using an SLM (selective laser melting), which comprises the steps of creating and generating a solid model by using modeling software, determining process parameters such as laser power, scanning speed, slice height, scanning interval and the like for manufacturing the titanium alloy bone tissue engineering implant with the micron-sized topological porous structure by adjusting default values of the laser power, the scanning speed, the slice height and the scanning interval of selected area laser melting equipment, introducing the created solid model into layered slice software and setting the slice height to obtain processing path data, introducing the processing path data into the selected area laser melting equipment, and inputting the determined laser power, scanning speed and scanning interval into the selected area laser melting equipment for processing. The pore size of the manufactured micron-sized regular hole is less than or equal to twice the laser spot size of the used selective laser melting equipment, and the minimum pore size of the manufactured micron-sized random hole is less than or equal to twice the laser spot size of the used selective laser melting equipment.

Description

Method for manufacturing titanium alloy bone tissue engineering implant with micron-sized topological porous structure by SLM (Selective laser melting)
Technical Field
The invention belongs to the technical field of preparation of bone tissue engineering implants, and particularly relates to a method for manufacturing a titanium alloy bone tissue engineering implant with a micron-sized topological porous structure by using SLM (selective laser sintering).
Background
With the continuous development of bone tissue repair and reconstruction technology, more and more medical metal materials are widely applied due to excellent mechanical properties. Medical metal materials are generally used for repairing bone tissues of force bearing parts, but are often designed into porous structures due to the stress shielding phenomenon caused by the high elastic modulus of the medical metal materials. It is now well established that porous structures can improve the biocompatibility of implanted materials. On one hand, the porous structure can provide necessary living space for the adhesion, migration and proliferation of bone cells, and on the other hand, the porous structure can also provide a transmission channel for nutrition and metabolites for the propagation and metabolism of cells. Therefore, the porous bone tissue engineering implant has an important position in bone tissue repair and reconstruction.
Selective Laser Melting (SLM), an advanced metal fabrication molding technique, has comparable advantages in the preparation of porous bone tissue engineering implants, and is therefore a commonly used method for the preparation of porous bone tissue engineering implants. The current methods of manufacturing porous bone tissue engineering implants using SLM are: creating and generating a porous model by adopting modeling software according to the hole shape, size and distribution mode required by the porous bone tissue engineering implant; and (3) taking the default values of the laser power, the scanning speed, the slice height and the scanning interval of the selective laser melting equipment as processing technological parameters, importing the created porous model of the bone tissue engineering implant into layered slice software, setting the slice height, obtaining processing path data, importing the processing path data into the selective laser melting equipment, inputting the default values of the laser power, the scanning speed and the scanning interval into the selective laser melting equipment, and then processing. However, the laser spot of the existing selective laser melting equipment is generally 100-400 μm, the laser spot of some selective laser melting equipment can be dozens of micrometers, the processing precision is +/-100 μm, regular holes with the pore size not more than 2 times of the laser spot size and random holes with the pore minimum size not more than 2 times of the laser spot size cannot be directly processed through a created porous model at present, and the pore minimum size refers to the shortest distance between pore profiles.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a method for manufacturing a titanium alloy bone tissue engineering implant with a micron-sized topological porous structure by using an SLM (selective laser melting), so as to solve the problem that regular holes with the pore size not more than 2 times of the laser spot size and random holes with the minimum pore size not more than 2 times of the laser spot size cannot be directly processed by using the conventional selective laser melting equipment through a porous model.
The technical idea of the invention is as follows: establishing and generating a solid model by adopting modeling software, determining technological parameters such as laser power, scanning speed, slicing height, scanning interval and the like for manufacturing the titanium alloy bone tissue engineering implant with the micron-sized topological porous structure by adjusting default values of the laser power, the scanning speed, the slicing height and the scanning interval of the selected area laser melting equipment, then introducing the established solid model into layered slicing software and setting the slicing height to obtain processing path data, introducing the processing path data into the selected area laser melting equipment, and inputting the determined laser power, scanning speed and scanning interval into the selected area laser melting equipment for processing.
The micron-sized topological porous structure comprises micron-sized regular holes and micron-sized random holes, the micron-sized regular holes are regularly arranged and uniformly distributed, and the size of a pore is less than or equal to twice the size of a laser spot of used selective laser melting equipment; the micron-sized random holes are distributed in a discretization mode, the pore diameters are different, the minimum pore size is not larger than twice the laser spot size of the used selective laser melting equipment, and the minimum pore size refers to the shortest distance of the pore outline.
The invention discloses a method for manufacturing a titanium alloy bone tissue engineering implant with a micron-sized topological porous structure by using an SLM (Selective laser melting), which comprises a method for manufacturing the titanium alloy bone tissue engineering implant with the micron-sized regular porous structure by using the SLM and a method for manufacturing the titanium alloy bone tissue engineering implant with the micron-sized random porous structure by using the SLM, and belongs to a general inventive concept.
The invention discloses a method for manufacturing a titanium alloy bone tissue engineering implant with a micron-sized regular pore structure by using an SLM (selective laser melting), wherein the size of the pore of the manufactured micron-sized regular pore is less than or equal to two times of the size of a laser spot of used selective laser melting equipment, and the method comprises the following steps:
(1) creating a bone tissue engineering implant model
According to the external shape and the size of the required bone tissue engineering implant with the micron-scale regular hole structure, a solid model for generating the external shape and the size is created by adopting modeling software;
(2) obtaining laser single scan melt channel size data
The method comprises the following steps of (1) obtaining the size data of a melting channel of laser single scanning by referring to the width and the depth of the melting channel through the following steps:
firstly, calculating a default linear energy density value p/v of the selective area laser melting equipment according to a laser power default value p and a scanning speed default value v of the selective area laser melting equipment;
selecting laser power and scanning speed within the adjustable range of the laser power and the scanning speed of the used selective laser melting equipment, wherein the selected laser power P and the selected scanning speed V are required to meet the condition that the laser line energy density value P/V of the selective laser melting equipment is 1-1.2 times of the default line energy density value;
thirdly, the default values of the laser power and the scanning speed selected in the second step and the slice height (powder spreading thickness) of the used selective laser melting equipment and the optional scanning interval in the adjustable range of the scanning interval of the used selective laser melting equipment are used as process parameters for processing the melt channel, the bone tissue engineering implant model created in the step (1) is used as a melt channel processing model, titanium alloy powder is used as a raw material, the process parameters are input into the selective laser melting equipment, and laser single-layer exposure scanning processing is carried out, so that the laser single-scanning melt channel is obtained;
measuring the laser obtained in the step III to scan the melting channel once, namely obtaining the width and the depth of the melting channel corresponding to the selected laser power and scanning speed;
(3) determining technological parameters for manufacturing titanium alloy bone tissue engineering implant with micron-sized regular pore structure
The technological parameters for manufacturing the titanium alloy bone tissue engineering implant with the micron-sized regular hole structure comprise laser power, scanning speed, slice height (powder spreading thickness) and scanning interval, wherein the laser power, the scanning speed and the slice height are the same as the laser power, the scanning speed and the slice height (powder spreading thickness) of the melt channel processing in the step (2), and the scanning interval is the melt channel width acquired in the step (2) plus the pore size required by the titanium alloy bone tissue engineering implant;
(4) titanium alloy bone tissue engineering implant for processing micron-sized regular pore structure
And (2) introducing the bone tissue engineering implant model created in the step (1) into layered slicing software, setting the slicing height (powder spreading thickness), obtaining processing path data, introducing the processing path data into selective laser melting equipment, inputting the determined laser power, scanning speed and scanning distance into the selective laser melting equipment, and processing by using titanium alloy powder as a raw material to obtain a micron-sized regular hole structure titanium alloy bone tissue engineering implant product with the required pore size being less than or equal to twice the laser spot size of the used selective laser melting equipment.
In the above method, the size of the melt channel is not required for each machining of the regular hole. Once the size of the channel at a particular laser power and scanning speed is obtained, the subsequent operations can be performed at that laser power and scanning speed without changing the channel size.
In the method, the average grain diameter of the titanium alloy powder in the step (4) is smaller than the laser spot size of the used selective laser melting equipment.
The invention discloses a method for manufacturing a titanium alloy bone tissue engineering implant with a micron-sized random pore structure by using an SLM (selective laser melting), wherein the minimum size of the pore of the manufactured micron-sized random pore is less than or equal to two times of the size of a laser spot of used selective laser melting equipment, the minimum size of the pore refers to the shortest distance between pore profiles, and the method comprises the following steps:
(1) creating a bone tissue engineering implant model
According to the external shape and the size of the required micron-scale random hole structure bone tissue engineering implant, a solid model for generating the external shape and the size is created by adopting modeling software;
(2) determining technological parameters for manufacturing micron-sized random pore structure titanium alloy bone tissue engineering implant
The technological parameters for manufacturing the titanium alloy bone tissue engineering implant with the micron-scale random hole structure comprise laser power, scanning speed, slice height (powder laying thickness) and scanning interval, wherein the scanning interval is a scanning interval default value of used selective laser melting equipment, at least one of the three technological parameters of the laser power, the scanning speed and the slice height (powder laying thickness) is not a default value of the used selective laser melting equipment, but the laser power and the scanning speed which are not default values are selected within an allowable adjusting range of the equipment, the slice height (powder laying thickness) which is not default value is selected within an allowable adjusting range of used layered slice software, and the determined technological parameters of the laser power, the scanning speed, the slice height (powder laying thickness) and the scanning interval are simultaneously selectedThe value of the energy density value is 5-30 W.s/mm (VHD) of the volume energy density value P/(VHD) of the selective laser melting equipment3Wherein, P is laser power, V is scanning speed, H is slice height (powder spreading thickness), and D is scanning interval;
(3) titanium alloy bone tissue engineering implant for processing micron-sized random pore structure
And (2) introducing the bone tissue engineering implant model created in the step (1) into layered slicing software, setting the slicing height (powder spreading thickness), obtaining processing path data, introducing the processing path data into selective laser melting equipment, inputting the determined laser power, scanning speed and scanning distance into the selective laser melting equipment, and processing by using titanium alloy powder as a raw material to obtain a micron-sized random hole structure titanium alloy bone tissue engineering implant product which meets the requirement that the minimum size of a pore is not more than two times of the laser spot size of the selective laser melting equipment.
In the method, the lapping state between adjacent layers is influenced by the value of the slice height (powder spreading thickness), the lapping state is a source of side random holes, when the slice height (powder spreading thickness) is larger than the default value of the slice height (powder spreading thickness) of used selective laser melting equipment, the side lapping is looser and looser along with the increase of the value of the slice height (powder spreading thickness), the random hole structure is more obvious, and the integral compactness of the titanium alloy bone tissue engineering implant is reduced, and the mechanical property is reduced. Therefore, the slice height determined in step (2) should be less than or equal to 2 times the default value of the slice height of the selected area laser melting device used.
In the method, the average grain diameter of the titanium alloy powder in the step (3) is smaller than the laser spot size of the used selective laser melting equipment.
The method has the following beneficial effects:
1. the invention provides a new method with different technical concepts from the prior art for manufacturing the titanium alloy bone tissue engineering implant with the micron-sized topological porous structure by using the SLM, and widens the size range of pores manufactured by the existing selective laser melting equipment.
2. The solid model is created by the method, and the solid model is simpler and more time-saving than the porous model, so that the modeling operation of manufacturing the titanium alloy bone tissue engineering implant with the micron-sized topological porous structure by the SLM is simplified, and the modeling time is shortened.
3. By using the method, regular holes with the pore size less than or equal to 2 times of the laser spot size and random holes with the minimum pore size less than or equal to 2 times of the laser spot size can be formed, and the requirements of people on the titanium alloy bone tissue engineering implant with the micron-sized topological porous structure can be better met.
Drawings
FIG. 1 is a Scanning Electron Microscope (SEM) image of a micron-sized titanium alloy bone tissue engineering implant with a regular pore structure prepared in example 1, example 2 and example 3, wherein (a) is the product prepared in example 1, (b) is the product prepared in example 2, and (c) is the product prepared in example 3;
FIG. 2 is a Scanning Electron Microscope (SEM) image of a micron-sized random pore structure titanium alloy bone tissue engineering implant prepared in example 4, example 5 and example 6, wherein (a) is the product prepared in example 4, (b) is the product prepared in example 5, and (c) is the product prepared in example 6;
fig. 3 is a Scanning Electron Microscope (SEM) image of a micron-sized random pore structure titanium alloy bone tissue engineering implant prepared in example 8, example 9 and example 10, wherein (a) is the product prepared in example 8, (b) is the product prepared in example 9, and (c) is the product prepared in example 10.
Detailed Description
The SLM manufacturing method of the micron-sized topological porous structure titanium alloy bone tissue engineering implant according to the present invention is further explained by the following embodiments with reference to the attached drawings.
In the following embodiment, adopted selective Laser melting equipment is a German Concept Laser MLab cutting R metal 3D printer, the type of the Laser is a fiber Laser, the diameter of a Laser spot is 50 mu m, the adjustable range of the equipment power is 10-100W, the adjustable range of the scanning speed is 10-7000 mm/s, the adjustable range of the scanning interval is 0.0014-13.6 mm, and the protective gas is nitrogen; the used raw material powder is Ti-6Al-4V spherical powder, the particle size range is 15-45 um, and the default Ti-6Al-4V powder printing process parameters of the equipment are as follows: laser power: 95W; scanning speed: 900 mm/s; slice height: 0.05 mm; scanning interval: 0.1 mm.
In the following embodiments, the modeling software is Solidworks, the layered slicing software is Materialise Magics, and the adjustable range of the slice height is 0.0001-500 mm.
Example 1
This example manufactures a Ti-6Al-4V bone tissue engineering scaffold with a regular pore structure having a pore size of 20 μm, by the following steps:
(1) creating bone tissue engineering scaffold models
A solid cubic model of 5mm multiplied by 2mm is created and generated by modeling software;
(2) obtaining laser single scan melt channel size data
The method comprises the following steps of (1) obtaining the size data of a melting channel of laser single scanning by referring to the width and the depth of the melting channel through the following steps:
calculating a default linear energy density value p/v of the selected area laser melting equipment which is 95/900-0.106 W.s/mm according to a laser power default value p and a scanning speed default value v of the used selected area laser melting equipment;
selecting laser power and scanning speed within the adjustable range of the laser power and the scanning speed of the used selective laser melting equipment, wherein the selected laser power P is 100W, the scanning speed V is 900mm/s, namely the energy density value P/V of the laser line of the selected process is 0.111 W.s/mm, and is 1.05 times of the default energy density value of the line;
thirdly, the determined processing technological parameters of the melting channel are as follows: the laser power P is 100W, the scanning speed V is 900mm/s, the slice height is 0.05mm, the scanning interval is 1mm, the bone tissue engineering implant model created in the step (1) is taken as a melt channel processing model, Ti-6Al-4V powder is taken as a raw material, the process parameters are input into selective laser melting equipment, and laser single-layer exposure scanning processing is carried out, so that the laser single-scanning melt channel is obtained;
measuring the melting channel scanned by the laser in one time, namely obtaining the melting channel with the width of 0.11mm and the depth of 0.12mm corresponding to the laser power of 100W and the scanning speed of 900 mm/s;
(3) determining technological parameters for manufacturing regular pore structure Ti-6Al-4V bone tissue engineering scaffold
The technological parameters for manufacturing the regular pore structure Ti-6Al-4V bone tissue engineering scaffold are laser power, scanning speed, slice height and scanning interval, the laser power, the scanning speed and the slice height are the same as those of the fusion channel processed in the step (2), and the scanning interval is 0.11mm in width of the fusion channel obtained in the step (2) and 0.13mm in size of 20 mu m (0.02mm) of the pore required by the Ti-6Al-4V bone tissue engineering scaffold;
(4) processing regular hole structure Ti-6Al-4V bone tissue engineering scaffold
And (2) introducing the bone tissue engineering scaffold model created in the step (1) into layered slicing software, setting the slicing height to be 0.05mm, obtaining processing path data, introducing the processing path data into selective laser melting equipment, inputting the determined laser power of 100W, the scanning speed of 900mm/s and the scanning distance of 0.13mm into the selective laser melting equipment, and processing by using Ti-6Al-4V powder as a raw material to obtain a Ti-6Al-4V bone tissue engineering scaffold product with a regular pore structure, wherein the pore size of most of the surface of the Ti-6Al-4V bone tissue engineering scaffold product is about 19 mu m, and a scanning electron microscope photo of the Ti-6Al-4V bone tissue engineering scaffold product is shown in a. As can be seen from the graph (a) in FIG. 1, the pores on the surface of the scaffold are uniformly distributed and regularly arranged.
Example 2
This example manufactured a Ti-6Al-4V bone tissue engineering scaffold having a regular pore structure with a pore size of 60 μm, in exactly the same procedure as in example 1. The difference from the embodiment 1 is that: the scanning distance determined in the step (3) is 0.11mm and the aperture of the bone tissue engineering scaffold required by the Ti-6Al-4V is 60 micrometers (0.06mm) and is 0.17 mm.
The regular pore structure Ti-6Al-4V bone tissue engineering scaffold manufactured in this example has a regular pore size of about 65 μm, and the scanning electron micrograph is shown in (b) of FIG. 1. As can be seen from the (b) diagram in FIG. 1, the pores on the surface of the scaffold are uniformly distributed and regularly arranged.
Example 3
This example manufactured a Ti-6Al-4V bone tissue engineering scaffold having a regular pore structure with a pore size of 100 μm, in exactly the same procedure as in example 1. The difference from the embodiment 1 is that: the scanning distance determined in the step (3) is 0.11mm and the aperture of 100 mu m (0.10mm) required by the Ti-6Al-4V bone tissue engineering scaffold is 0.21 mm.
The regular pore structure Ti-6Al-4V bone tissue engineering scaffold manufactured in this example has a surface with regular pores mostly having a pore size of about 105 μm, and the scanning electron micrograph is shown in (c) of FIG. 1. As can be seen from the (c) diagram in FIG. 1, the pores on the surface of the scaffold are uniformly distributed and regularly arranged.
Example 4
In this embodiment, a Ti-6Al-4V bone tissue engineering scaffold with a random pore structure is manufactured, wherein the minimum pore size of the micron-sized random pores is less than or equal to 100 μm, and the steps are as follows:
(1) creating a bone tissue engineering implant model
A solid cubic model of 5mm multiplied by 2mm is created and generated by modeling software;
(2) determining technological parameters for manufacturing random pore structure Ti-6Al-4V bone tissue engineering scaffold
The technological parameters for manufacturing the random pore structure Ti-6Al-4V bone tissue engineering scaffold comprise laser power, scanning speed, slice height and scanning interval; in the embodiment, a scanning distance default value of 0.1mm, a slice height default value of 0.05mm and a scanning speed default value of 900mm/s of the used selective laser melting equipment are used as processing technological parameters, and the volume energy density value P/(VHD) of the used selective laser melting equipment is 5-30 W.s/mm3Selecting the laser power of 59W within the adjustable power range of 10-100W of the equipment, namely selecting the volume energy density value of the selected process as 59/(900 multiplied by 0.05 multiplied by 0.1) ═ 13.11W · s/mm3；
(3) Engineering scaffold for processing random pore structure Ti-6Al-4V bone tissue
And (2) introducing the bone tissue engineering scaffold model created in the step (1) into layered slicing software, setting the slicing height to be 0.05mm, obtaining processing path data, introducing the processing path data into selective laser melting equipment, inputting the determined laser power of 59W, the scanning speed of 900mm/s and the scanning distance of 0.1mm into the selective laser melting equipment, and processing by using Ti-6Al-4V powder as a raw material to obtain a Ti-6Al-4V bone tissue engineering scaffold product with a random hole structure on the surface, wherein a scanning electron microscope photo of the product is shown in a picture (a) in figure 2. As can be seen from the diagram (a) in fig. 2, the random holes are formed by combining three states of powder melting, semi-melting and non-melting, the number of holes is large, gaps among strip-shaped ravines are large, and the minimum size of most holes is less than or equal to 50 μm.
Example 5
In this example, a Ti-6Al-4V bone tissue engineering scaffold with a random pore structure was fabricated, wherein the minimum pore size of the micron-sized random pores was no greater than 100 μm, and the procedure was exactly the same as in example 4. The difference from the embodiment 4 is that: in the step (2), the selected laser power is 41W, and the volume energy density value of the selected process is 41/(900 × 0.05 × 0.1) ═ 9.11W · s/mm3. Namely, the determined processing technological parameters are as follows: laser power 41W, scanning speed 900mm/s, slice height 0.05mm, scanning interval 0.1 mm.
The scanning electron micrograph of the random pore structure Ti-6Al-4V bone tissue engineering scaffold manufactured in the embodiment is shown in a graph (b) in FIG. 2, and as can be seen from the graph (b) in FIG. 2, compared with the embodiment 4, the number of the melt channel discontinuities is increased, the number of the pores is more, the shape of the pores tends to be annular, and the minimum size of most pores is less than or equal to 60 μm.
Example 6
In this example, a Ti-6Al-4V bone tissue engineering scaffold with a random pore structure was fabricated, wherein the minimum pore size of the micron-sized random pores was no greater than 100 μm, and the procedure was exactly the same as in example 4. The difference from the embodiment 4 is that: in the step (2), the selected laser power is 37W, and the volume energy density value of the selected process is 37/(900 × 0.05 × 0.1) ═ 8.22W · s/mm3. Namely, the determined processing technological parameters are as follows: the laser power is 37W, the scanning speed is 900mm/s, the slice height is 0.05mm, and the scanning interval is 0.1 mm.
The scanning electron micrograph of the random pore structure Ti-6Al-4V bone tissue engineering scaffold manufactured in the embodiment is shown in a graph (c) in FIG. 2, and as can be seen from the graph (c) in FIG. 2, compared with the embodiment 4, the number of the melt channel discontinuities is increased, the number of the pores is more, the shape of the pores tends to be annular, and the minimum size of most pores is less than or equal to 70 μm.
Example 7
In this embodiment, a Ti-6Al-4V bone tissue engineering scaffold with a random pore structure is manufactured, wherein the minimum pore size of the micron-sized random pores is less than or equal to 100 μm, and the steps are as follows:
(1) creating a bone tissue engineering implant model
A solid cubic model of 5mm multiplied by 2mm is created and generated by modeling software;
(2) determining technological parameters for manufacturing random pore structure Ti-6Al-4V bone tissue engineering scaffold
The technological parameters for manufacturing the random pore structure Ti-6Al-4V bone tissue engineering scaffold comprise laser power, scanning speed, slice height and scanning interval; in the embodiment, a default value of laser power 95W, a default value of scanning distance 0.1mm and a default value of slice height 0.05mm of the used selective laser melting equipment are used as processing technological parameters, and the volume energy density value P/(VHD) of the used selective laser melting equipment is 5-30 W.s/mm3The scanning speed is 2311mm/s within the adjustable range of the scanning speed of the equipment from 10 mm/s to 7000mm/s, namely the volume energy density value of the selected process is 95/(2311 multiplied by 0.05 multiplied by 0.1) to 8.22 W.s/mm3；
(3) Engineering scaffold for processing random pore structure Ti-6Al-4V bone tissue
And (2) introducing the bone tissue engineering scaffold model created in the step (1) into layered slicing software, setting the slicing height to be 0.05mm, obtaining processing path data, introducing the processing path data into selective laser melting equipment, inputting the determined laser power of 95W, the scanning speed of 2311mm/s and the scanning distance of 0.1mm into the selective laser melting equipment, and processing by using Ti-6Al-4V powder as a raw material to obtain a Ti-6Al-4V bone tissue engineering scaffold product with a random hole structure on the surface, wherein the morphology of the engineering scaffold is similar to that of the embodiment 6, the melting channel is discontinuous, the number of holes is large, the shape tends to be annular, and the minimum size of most holes is less than or equal to 70 mu m.
Example 8
In this embodiment, a Ti-6Al-4V bone tissue engineering scaffold with a random pore structure is manufactured, wherein the minimum pore size of the micron-sized random pores is less than or equal to 100 μm, and the steps are as follows:
(1) creating a bone tissue engineering implant model
A solid cubic model of 5mm multiplied by 2mm is created and generated by modeling software;
(2) determining technological parameters for manufacturing random pore structure Ti-6Al-4V bone tissue engineering scaffold
The technological parameters for manufacturing the random pore structure Ti-6Al-4V bone tissue engineering scaffold comprise laser power, scanning speed, slice height and scanning interval; in the embodiment, a default value of laser power of 95W, a default value of scanning speed of 900mm/s and a default value of scanning distance of 0.1mm of the used selective laser melting equipment are used as processing technological parameters, and the volume energy density value P/(VHD) of the used selective laser melting equipment is 5-30 W.s/mm3Selecting the slice height of 0.060mm within the adjustable range of slicing software Materialise Magics, namely the volume energy density value of the selected process is 95/(900 multiplied by 0.06 multiplied by 0.1) to 17.59 W.s/mm3；
(3) Engineering scaffold for processing random pore structure Ti-6Al-4V bone tissue
And (2) introducing the bone tissue engineering scaffold model created in the step (1) into layered slicing software, setting the slicing height to be 0.06mm, obtaining processing path data, introducing the processing path data into selective area laser melting equipment, inputting the determined laser power of 95W, the scanning speed of 900mm/s and the scanning distance of 0.1mm into the selective area laser melting equipment, and processing by using Ti-6Al-4V powder as a raw material to obtain a Ti-6Al-4V bone tissue engineering scaffold product with a random hole structure on the surface, wherein a scanning electron microscope photo of the product is shown in a picture (a) in figure 3. The cross section of the obtained product has a few holes, and the cross section melting channel is loosely overlapped.
Example 9
In this example, a Ti-6Al-4V bone tissue engineering scaffold with a random pore structure was fabricated, wherein the minimum pore size of the micron-sized random pores was no greater than 100 μm, and the procedure was exactly the same as in example 8. The difference from the example 8 is that: in the step (2), the selected slice height is 0.075mm, and the volume energy density value of the selected process is 95/(900 × 0.075 × 0.1) ═ 14.07W · s/mm3. Namely, the determined processing technological parameters are as follows: the laser power is 95W, the scanning speed is 900mm/s, the slice height is 0.075mm, and the scanning interval is 0.1 mm.
The scanning electron micrograph of the random pore structure Ti-6Al-4V bone tissue engineering scaffold manufactured in this example is shown in fig. 3 (b), and it can be seen from fig. 3 (b) that the number of pores existing in the cross section of the finally obtained product is larger, the surface is rougher, and the lap joint of the cross section is looser compared with the cross section of example 8.
Example 10
In this example, a Ti-6Al-4V bone tissue engineering scaffold with a random pore structure was fabricated, wherein the minimum pore size of the micron-sized random pores was no greater than 100 μm, and the procedure was exactly the same as in example 8. The difference from the example 8 is that: in the step (2), the selected slice height is 0.100mm, and the volume energy density value of the selected process is 95/(900 × 0.100 × 0.1) ═ 10.56W · s/mm3. Namely, the determined processing technological parameters are as follows: the laser power is 95W, the scanning speed is 900mm/s, the slice height is 0.100mm, and the scanning interval is 0.1 mm.
The scanning electron micrograph of the random pore structure Ti-6Al-4V bone tissue engineering scaffold manufactured in the embodiment is shown in a graph (c) in FIG. 3, and as can be seen from the graph (c) in FIG. 3, compared with the cross section of the embodiment 9, the number of pores existing in the finally obtained sample cross section is larger, the size and the position are random, the surface is rougher, and the lap joint of the cross section is looser.
Comparative example 1
The procedure of this comparative example is as follows:
(1) creating a model
A solid cubic model of 5mm multiplied by 2mm is created and generated by modeling software;
(2) determination of process parameters
Taking a laser power default value of 95W, a scanning distance default value of 0.1mm, a slice height default value of 0.05mm and a scanning speed default value of 900mm/s of the used selective laser melting equipment as processing technological parameters;
(3) machining
And (2) introducing the entity model created in the step (1) into layered slicing software, setting the slicing height to be 0.05mm, obtaining processing path data, introducing the processing path data into selective laser melting equipment, inputting the determined laser power of 95W, the scanning speed of 900mm/s and the scanning distance of 0.1mm into the selective laser melting equipment, processing by using Ti-6Al-4V powder as a raw material, and finishing the surface of the obtained product.
Comparative example 2
The procedure of this comparative example is as follows:
(1) creating a model
A 5mm multiplied by 2mm orthogonal porous cube is created and generated by modeling software, and the size of the designed pore diameter is 50 mu m;
(2) determination of process parameters
Taking a laser power default value of 95W, a scanning distance default value of 0.1mm, a slice height default value of 0.05mm and a scanning speed default value of 900mm/s of the used selective laser melting equipment as processing technological parameters;
(3) machining
And (2) introducing the entity model created in the step (1) into layered slicing software, setting the slicing height to be 0.05mm, obtaining processing path data, introducing the processing path data into selective laser melting equipment, inputting the determined laser power of 95W, the scanning speed of 900mm/s and the scanning distance of 0.1mm into the selective laser melting equipment, and processing by using Ti-6Al-4V powder as a raw material, wherein the surface of the obtained product has no obvious pores and is basically the same as that of the product obtained in the comparative example 1.
Comparative example 3
The procedure of this comparative example is as follows:
(1) creating a model
A 5mm multiplied by 2mm orthogonal porous cube is created and generated by modeling software, and the size of the designed pore diameter is 100 mu m;
(2) determination of process parameters
Taking a laser power default value of 95W, a scanning distance default value of 0.1mm, a slice height default value of 0.05mm and a scanning speed default value of 900mm/s of the used selective laser melting equipment as processing technological parameters;
(3) machining
And (2) introducing the entity model created in the step (1) into layered slicing software, setting the slicing height to be 0.05mm, obtaining processing path data, introducing the processing path data into selective laser melting equipment, inputting the determined laser power of 95W, the scanning speed of 900mm/s and the scanning distance of 0.1mm into the selective laser melting equipment, and processing by using Ti-6Al-4V powder as a raw material, wherein the surface of the obtained product has few pores, the pores are randomly arranged, a designed orthogonal porous structure is not formed, and the pore size is far smaller than the designed pore size.

Claims (5)

  1. The method for manufacturing the titanium alloy bone tissue engineering implant with the micron-sized regular hole structure by using the SLM is characterized in that the pore size of the micron-sized regular hole is less than or equal to two times of the laser spot size of the used selective laser melting equipment, and the method comprises the following steps:
    (1) creating a bone tissue engineering implant model
    According to the external shape and the size of the required bone tissue engineering implant with the micron-scale regular hole structure, a solid model for generating the external shape and the size is created by adopting modeling software;
    (2) obtaining laser single scan melt channel size data
    The method comprises the following steps of (1) obtaining the size data of a melting channel of laser single scanning by referring to the width and the depth of the melting channel through the following steps:
    firstly, calculating a default linear energy density value p/v of the selective area laser melting equipment according to a laser power default value p and a scanning speed default value v of the selective area laser melting equipment;
    selecting laser power and scanning speed within the adjustable range of the laser power and the scanning speed of the used selective laser melting equipment, wherein the selected laser power P and the selected scanning speed V are required to meet the condition that the laser line energy density value P/V of the selective laser melting equipment is 1-1.2 times of the default line energy density value;
    thirdly, the default values of the laser power and the scanning speed selected in the second step, the slice height of the used selective laser melting equipment and the optional scanning distance in the adjustable range of the scanning distance of the used selective laser melting equipment are taken as process parameters for processing the melt channel, the bone tissue engineering implant model created in the step (1) is taken as a melt channel processing model, titanium alloy powder is taken as a raw material, the process parameters are input into the selective laser melting equipment, and laser single-layer exposure scanning processing is carried out, so that the laser single-scanning melt channel is obtained;
    measuring the laser obtained in the step III to scan the melting channel once, namely obtaining the width and the depth of the melting channel corresponding to the selected laser power and scanning speed;
    (3) determining technological parameters for manufacturing titanium alloy bone tissue engineering implant with micron-sized regular pore structure
    The technological parameters for manufacturing the titanium alloy bone tissue engineering implant with the micron-sized regular hole structure comprise laser power, scanning speed, slice height and scanning interval, wherein the laser power, the scanning speed and the slice height are the same as those of the laser power, the scanning speed and the slice height processed in the melting channel in the step (2), and the scanning interval is the melting channel width acquired in the step (2) plus the pore size required by the titanium alloy bone tissue engineering implant;
    (4) titanium alloy bone tissue engineering implant for processing micron-sized regular pore structure
    And (2) leading the bone tissue engineering implant model created in the step (1) into layered slicing software and setting the slicing height to obtain processing path data and leading the processing path data into selective laser melting equipment, inputting the determined laser power, scanning speed and scanning distance into the selective laser melting equipment, and processing by using titanium alloy powder as a raw material to obtain a micron-sized regular hole structure titanium alloy bone tissue engineering implant product which meets the requirement that the size of a pore is not more than two times of the size of a laser spot of the selective laser melting equipment.
  2. 2. The SLM method for manufacturing micron-sized titanium alloy bone tissue engineering implant with regular pore structure according to claim 1, characterized in that the average particle size of the titanium alloy powder in step (4) should be smaller than the laser spot size of the used selective laser melting equipment.
  3. The method for manufacturing the titanium alloy bone tissue engineering implant with the micron-sized random hole structure by using the SLM is characterized in that the minimum pore size of the micron-sized random hole is less than or equal to two times of the laser spot size of used selective laser melting equipment, wherein the minimum pore size refers to the shortest distance between pore profiles, and the method comprises the following steps of:
    (1) creating a bone tissue engineering implant model
    According to the external shape and the size of the required micron-scale random hole structure bone tissue engineering implant, a solid model for generating the external shape and the size is created by adopting modeling software;
    (2) determining technological parameters for manufacturing micron-sized random pore structure titanium alloy bone tissue engineering implant
    The technical parameters for manufacturing the titanium alloy bone tissue engineering implant with the micron-scale random hole structure comprise laser power, scanning speed, slice height and scanning interval, wherein the scanning interval is a scanning interval default value of used selective laser melting equipment, at least one of the three technical parameters of the laser power, the scanning speed and the slice height is not a default value of the used selective laser melting equipment, but the laser power and the scanning speed which are not default values are selected within an allowable adjusting range of the equipment, the slice height which is not a default value is selected within an allowable adjusting range of used layered slice software, and the determined technical parameters of the laser power, the scanning speed, the slice height and the scanning interval value meet the requirement that the volume energy density value P/(VHD) of the selective laser melting equipment is 5-30 W.s/mm3Wherein P is laser power, V is scanning speed, H is slice height, and D is scanning interval;
    (3) titanium alloy bone tissue engineering implant for processing micron-sized random pore structure
    And (2) leading the bone tissue engineering implant model created in the step (1) into layered slicing software and setting the slicing height to obtain processing path data and leading the processing path data into selective laser melting equipment, inputting the determined laser power, scanning speed and scanning distance into the selective laser melting equipment, and processing by using titanium alloy powder as a raw material to obtain a micron-sized random hole structure titanium alloy bone tissue engineering implant product which meets the requirement that the minimum size of a pore is not more than two times of the laser spot size of the used selective laser melting equipment.
  4. 4. The SLM method for manufacturing micron-sized random hole structure titanium alloy bone tissue engineering implant according to claim 3, characterized in that the slice height determined in step (2) should be less than or equal to 2 times the default value of the slice height of the used selective laser melting device.
  5. 5. The SLM manufacturing method for micron-sized random pore structure titanium alloy bone tissue engineering implant according to claim 3 or 4, characterized in that the average particle size of the titanium alloy powder in step (3) should be smaller than the laser spot size of the used selective laser ablation device.
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