Metal / ceramic composite porous implant and preparation method thereof

Abstract

The invention discloses a metal / ceramic composite porous implant and a preparation method thereof.The method comprises the steps that firstly, original ceramic powder is subjected to structure reconstruction through a gel-casting method, regenerated ceramic powder which is wide in particle size range and porous in surface is prepared, and the reconstruction process enables the surfaces of ceramic particles to form micron-sized coarse structures; on one hand, the mechanical interlocking effect with metal powder is improved, a basis of high interface bonding force is provided for subsequent extrusion forming, and meanwhile, a porous implant can be constructed easily; and then, after the regenerated ceramic powder, metal powder and a binder are mixed, a hierarchical pore structure is constructed by combining a direct-writing extrusion forming process and high-temperature sintering treatment, and the hierarchical pore structure is effectively formed. According to the method, the multi-stage composite porous implant is successfully prepared by combining regeneration treatment of ceramic powder with a direct-writing extrusion process and high-temperature sintering treatment, and integrated forming of a personalized appearance and a complex microstructure is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of bio-additive manufacturing and relates to a metal / ceramic composite porous implant and a preparation method thereof. Background Art

[0002] With the accelerated aging of the population, the faster pace of life, and the deteriorating urban environment, tens of millions of patients suffer bone defects each year due to severe trauma, tumor resection, or congenital diseases. This severely impacts their health and quality of life, becoming a serious social problem. Clinically, artificial bone prostheses are primarily used to repair and reconstruct bone defects.

[0003] Currently, metal materials remain the most widely used for the repair and reconstruction of large bone defects due to their excellent mechanical properties. These materials primarily include stainless steel, cobalt-based alloys, tantalum, titanium, and titanium alloys. Stainless steel and cobalt-based alloys have drawbacks such as insufficient biocompatibility, poor corrosion resistance, and a high elastic modulus that can easily lead to stress shielding. Tantalum has an extremely high melting point, making porous implants difficult to manufacture and expensive, hindering widespread clinical application. Titanium alloys offer excellent mechanical strength and biocompatibility, but they readily release toxic ions such as aluminum and vanadium in the body, posing potential risks for long-term implantation. Pure titanium is safer and more stable, but due to its bioinertness, it still exhibits insufficient osteoconductivity after implantation. Calcium-phosphorus-based bioceramics, whose composition is similar to the inorganic mineralized phase of bone, exhibit excellent biocompatibility and osteoconductivity and are widely used as bone repair materials. However, bioceramics are brittle and lack mechanical strength, making them unsuitable for load-bearing bone defect repair.

[0004] In order to break through the performance bottleneck of a single material, researchers have combined metals with ceramics to construct bone repair materials that have both mechanical support and bioactivity. Taking titanium-based bioceramic composite scaffolds as an example, the construction forms of titanium-based bioceramic composite scaffolds are mainly divided into two categories. One type is to deposit a layer of bioactive ceramic coating on the surface of the porous titanium implant matrix to improve the bioactivity of the implant, but the difference in thermal expansion coefficient between the titanium matrix and the ceramic coating material and the coating preparation process will affect the interface bonding strength, and there is a problem of coating shedding after long-term implantation. The other type uses powder metallurgy or injection molding to mix and sinter titanium powder and ceramic powder, but traditional processes (such as hot pressing sintering, spark plasma sintering) are difficult to accurately control the pore structure (such as pore size gradient, connectivity), and the resulting products are mostly dense entities that cannot mimic the three-dimensional porous characteristics of natural trabecular bone, restricting bone cell growth and nutrient delivery. Summary of the Invention

[0005] In response to the problems existing in the prior art, the present invention provides a metal / ceramic composite porous implant and a preparation method thereof, thereby solving the technical problem in the prior art that it is difficult to accurately control the pore structure of metal / ceramic composite bone repair materials.

[0006] The present invention is achieved through the following technical solutions:

[0007] A method for preparing a metal / ceramic composite porous implant comprises the following steps:

[0008] S1: dissolving acrylamide, N,N'-methylenebisacrylamide, and sodium polyacrylate in water to obtain solution A; adding ceramic powder to solution A and continuing to stir; after the ceramic powder is completely dissolved in solution A without agglomeration, adding ammonium persulfate and N,N,N,N-tetramethylethylenediamine and stirring evenly to obtain slurry B; allowing the slurry B to stand and solidify, drying, degreasing, and then sintering to obtain regenerated ceramic blocks C; washing, drying, crushing, grinding, and sieving the regenerated ceramic blocks C to obtain regenerated ceramic powder;

[0009] S2: uniformly mixing the recycled ceramic powder, metal powder and binder to obtain a mixed slurry;

[0010] S3: Based on a pre-constructed implant model, the mixed slurry is subjected to direct extrusion molding to obtain a metal / ceramic composite implant blank, and the metal / ceramic composite implant blank is subjected to vacuum high-temperature sintering treatment to obtain the metal / ceramic composite porous implant.

[0011] Preferably, in step S1, the ratio of acrylamide to N,N'-methylenebisacrylamide is (1-10):(10-1); and the mass ratio of sodium acrylate to ceramic powder is 1:(50-1000).

[0012] Preferably, in step S1, the degreasing treatment is performed at a temperature of 200 to 600° C. and for a time of 0.5 to 5 hours.

[0013] Preferably, in step S1, the sintering treatment temperature is 700-2000° C., and the time is 2-6 hours.

[0014] Preferably, the particle size of the recycled ceramic powder is 0.1 to 120 μm; the particle size of the metal powder is 0.1 to 200 μm.

[0015] Preferably, the ceramic powder is at least one of hydroxyapatite, tricalcium phosphate, silicon dioxide, magnesium oxide and aluminum oxide; the metal powder is at least one of tantalum powder, titanium powder, niobium powder, beryllium powder, magnesium powder, zinc powder, tantalum alloy, titanium alloy, niobium alloy, beryllium alloy, magnesium alloy and zinc alloy.

[0016] Preferably, the metal powder accounts for 1% to 99% of the total volume of the metal powder and the recycled ceramic powder.

[0017] Preferably, in step S3, during the direct writing extrusion forming process, the nozzle moving speed is 0.5-45 mm / s, the plunger feeding speed is 0.01-0.8 mm / s, and the printing layer height is 0.2-1 mm.

[0018] Preferably, in step S3, the vacuum high-temperature sintering process is specifically as follows: first, the temperature is raised from room temperature to 150-400°C at a rate of 2-30°C / min, and then kept warm for 0.5-5h; then the temperature is raised to 500-800°C at a rate of 2-30°C / min, and kept warm for 0.5-5h; finally, the temperature is raised to 600-2000°C at a rate of 5-80°C / min, and kept warm for 2-5h, and then the high-temperature sintering process is completed after the furnace is cooled to room temperature; the vacuum degree is 5*10 -2 ~1*10 -3 Pa.

[0019] A metal / ceramic composite porous implant is prepared by the above method; the metal / ceramic composite porous implant comprises a microporous structure with a pore size of 1 to 50 μm and a macroporous structure with a pore size of 100 to 1000 μm, and the porosity of the metal / ceramic composite porous implant is 30% to 90%.

[0020] Compared with the prior art, the present invention has the following beneficial technical effects:

[0021] The present invention discloses a method for preparing a metal / ceramic composite porous implant. The method first uses a gel injection molding method to restructure the original ceramic powder to prepare a recycled ceramic powder with a wide particle size range and a porous surface. This reconstruction process forms a micron-level rough structure on the surface of the ceramic particles, which on the one hand enhances the mechanical interlocking effect with the metal powder, provides a basis for high interface bonding force for subsequent extrusion molding, and is conducive to the construction of a porous implant. Then, the recycled ceramic powder, metal powder and a binder are mixed, and a multi-level pore structure is constructed by combining a direct writing extrusion molding process and a high-temperature sintering treatment. The direct writing extrusion molding process is conducive to the construction of a pore structure with a size of 200 to 300 μm. After the recycled ceramic powder is subjected to a high-temperature sintering treatment, a pore structure with a size of 50 to 100 μm is constructed, effectively forming a multi-level pore structure. The method successfully prepares a multi-level composite porous implant by combining the regeneration treatment of the ceramic powder with the direct writing extrusion process and the high-temperature sintering treatment, realizing the integrated forming of personalized appearance and complex microstructure.

[0022] Furthermore, the ratio of acrylamide to N,N'-methylenebisacrylamide is (1-10):(10-1), which can achieve excellent curing and cross-linking effects; the mass ratio of sodium polyacrylate to ceramic powder is 1:(50-1000), which can make the ceramic powder evenly dispersed.

[0023] Furthermore, the degreasing treatment is performed at a temperature of 200 to 600° C. and for a time of 0.5 to 5 hours, so that organic matter can be removed as much as possible through degreasing.

[0024] Furthermore, the sintering treatment temperature is 700-2000° C. and the time is 2-6 hours, which can effectively control the sintering pores.

[0025] Furthermore, the particle size of the recycled ceramic powder is 1 to 120 μm, which can make the dispersibility and fluidity of the printing slurry excellent and the sintering holes easy to control; the particle size of the metal powder is 0.1 to 200 μm, which can make the fusion between the powders better and improve the mechanical strength.

[0026] Furthermore, the ceramic powder is at least one of hydroxyapatite, tricalcium phosphate, silicon dioxide, magnesium oxide, and aluminum oxide, which can improve the biological properties of the composite stent; the metal powder is at least one of tantalum powder, titanium powder, niobium powder, beryllium powder, magnesium powder, zinc powder, tantalum alloy, titanium alloy, niobium alloy, beryllium alloy, magnesium alloy, and zinc alloy, which can improve the mechanical properties of the composite stent;

[0027] Furthermore, the metal powder accounts for 1% to 99% of the total volume of the metal powder and the recycled ceramic powder, which enables the mechanical properties of the composite stent to be regulated over a wide range.

[0028] Furthermore, during the direct writing extrusion forming process, the nozzle moving speed is 0.5-45 mm / s, the plunger feeding speed is 0.01-0.8 mm / s, and the printing layer height is 0.2-1 mm, which can achieve a good printing effect of the blank bracket.

[0029] Furthermore, the vacuum high temperature sintering process is specifically as follows: first, the temperature is raised from room temperature to 150-400°C at a rate of 2-30°C / min, and then kept warm for 0.5-5h; then the temperature is raised to 500-800°C at a rate of 2-30°C / min, and kept warm for 0.5-5h; finally, the temperature is raised to 600-2000°C at a rate of 5-80°C / min, and kept warm for 2-5h, and then the high temperature sintering process is completed after the furnace is cooled to room temperature; the vacuum degree is 5*10 -2 ~1*10 -3 Pa can make the composite scaffold have fewer impurities and better mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0031] Figure 1 This is a scanning electron microscope image of the raw material tantalum powder of Example 1 of the present invention;

[0032] Figure 2 This is a particle size distribution diagram of the raw material tantalum powder of Example 1 of the present invention;

[0033] Figure 3 This is the XRD pattern of the tantalum powder as the raw material in Example 1 of the present invention;

[0034] Figure 4 This is a scanning electron microscope image of tricalcium phosphate (TCP powder), a raw material of Example 1 of the present invention;

[0035] Figure 5 This is a particle size distribution diagram of tricalcium phosphate (TCP powder), a raw material of Example 1 of the present invention;

[0036] Figure 6 1 is a macroscopic morphology diagram of the metal / ceramic composite porous implant prepared in Example 1 of the present invention before and after sintering;

[0037] Figure 7 This is an electron microscope image of the microstructure of the metal / ceramic composite porous implant prepared in Example 2 of the present invention;

[0038] Figure 8 This is an electron microscope image of the microstructure of the metal / ceramic composite porous implant prepared in Example 3 of the present invention;

[0039] Figure 9 This is an electron microscope image of the microstructure of the metal / ceramic composite porous implant prepared in Example 4 of the present invention;

[0040] Figure 10 This is an electron micrograph of cell adhesion and growth on the surface of the metal / ceramic composite porous implant prepared in Example 2 of the present invention, wherein D1, D3, and D7 represent 1 day, 3 days, and 7 days of culture, respectively;

[0041] Figure 11 This is an electron micrograph of cell adhesion and growth on the surface of the metal / ceramic composite porous implant prepared in Example 3 of the present invention, wherein D1, D3, and D7 represent 1 day, 3 days, and 7 days of culture, respectively;

[0042] Figure 12 This is an electron micrograph of cell adhesion and growth on the surface of the metal / ceramic composite porous implant prepared in Example 4 of the present invention, wherein D1, D3, and D7 represent 1 day, 3 days, and 7 days of culture, respectively;

[0043] Figure 13The porosity of the metal / ceramic composite porous implants prepared in Examples 5 to 16 of the present invention, where B95Ti represents 95% of the total volume of titanium powder and recycled TCP powder;

[0044] Figure 14 This is a microscopic morphology of the Ti / TCP composite porous implant prepared in Example 5 of the present invention. DETAILED DESCRIPTION

[0045] To facilitate understanding of the features and effects of the present invention by those skilled in the art, the following provides a general description and definition of the terms and expressions used in the specification and claims. Unless otherwise indicated, all technical and scientific terms used herein have the ordinary meanings as understood by those skilled in the art regarding the present invention. In the event of conflict, the definitions in this specification shall prevail.

[0046] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0047] Herein, all features such as values, amounts, amounts, and concentrations defined in numerical ranges or percentage ranges are for brevity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to include and specifically disclose all possible subranges and individual values ​​within the range (including integers and fractions).

[0048] In this document, unless otherwise specified, “include,” “including,” “contains,” “has” or similar terms cover the meanings of “consisting of” and “mainly consisting of,” for example, “A includes a” covers the meanings of “A includes a and other” and “A only includes a.”

[0049] In this document, for the sake of brevity, not all possible combinations of the various technical features in each embodiment or example are described. Therefore, as long as there are no contradictions in the combination of these technical features, the various technical features in each embodiment or example can be combined in any way, and all possible combinations should be considered to be within the scope of this specification.

[0050] The present invention provides a method for preparing a metal / ceramic composite porous implant, comprising the steps of:

[0051] S1: dissolving acrylamide, N,N'-methylenebisacrylamide and sodium polyacrylate in water to obtain solution A; adding ceramic powder to solution A and continuing to stir, until the ceramic powder is completely dissolved in solution A without agglomeration, adding ammonium persulfate and N,N,N,N-tetramethylethylenediamine, and stirring evenly to obtain slurry B; after the slurry B is allowed to stand and solidify, it is dried and degreased at 200-600°C for 0.5-5h, and then sintered at 700-2000°C for 2-6h to obtain recycled ceramic blocks C with a particle size of 0.1-120μm, and the recycled ceramic blocks C are cleaned, dried, crushed, ground and sieved to obtain recycled ceramic powder;

[0052] The ratio of acrylamide to N,N'-methylenebisacrylamide is (1-10):(10-1); and the mass ratio of sodium acrylate to ceramic powder is 1:(50-1000).

[0053] The ceramic powder is at least one of hydroxyapatite, tricalcium phosphate, silicon dioxide, magnesium oxide and aluminum oxide;

[0054] S2: uniformly mixing the recycled ceramic powder, the metal powder with a particle size of 0.1 to 200 μm, and the binder to obtain a mixed slurry;

[0055] The metal powder is at least one of tantalum powder, titanium powder, niobium powder, beryllium powder, magnesium powder, zinc powder, tantalum alloy, titanium alloy, niobium alloy, beryllium alloy, magnesium alloy and zinc alloy.

[0056] The metal powder accounts for 1% to 99% of the total volume of the metal powder and the recycled ceramic powder.

[0057] The binder is at least one of sodium alginate, F127 polyether, polyvinyl alcohol, polyethylene glycol diacrylate, chitosan, gelatin, and carboxymethyl cellulose;

[0058] S3: Based on the pre-constructed implant model, the mixed slurry is subjected to direct writing extrusion molding. During the direct writing extrusion molding process, the nozzle moving speed is 0.5-45 mm / s, the plunger feeding speed is 0.01-0.8 mm / s, and the printing layer height is 0.2-1 mm to obtain a metal / ceramic composite implant blank. The metal / ceramic composite implant blank is subjected to vacuum high-temperature sintering treatment, specifically: first, the temperature is increased from room temperature to 150-400°C at a rate of 2-30°C / min, and then kept warm for 0.5-5h; then, the temperature is increased to 500-800°C at a rate of 2-30°C / min, and kept warm for 0.5-5h; finally, the temperature is increased to 600-2000°C at a rate of 5-80°C / min, and kept warm for 2-5h. After cooling to room temperature with the furnace, the high-temperature sintering treatment is completed; the vacuum degree is 5*10 -2 ~1*10 -3Pa, to prepare the metal / ceramic composite porous implant.

[0059] The present invention also discloses a metal / ceramic composite porous implant prepared by the above method. The metal / ceramic composite porous implant includes a microporous structure with a pore size of 1 to 50 μm and a macroporous structure with a pore size of 100 to 1000 μm. The porosity of the metal / ceramic composite porous implant is 30% to 90%.

[0060] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0061] The following examples were prepared using conventional instruments and equipment in the art. Experimental methods in the following examples, where specific conditions are not specified, were generally performed under conventional conditions or according to the conditions recommended by the manufacturer. The various raw materials used in the following examples, unless otherwise specified, were conventional commercially available products, with specifications conventional in the art. In the present specification and the following examples, unless otherwise specified, "%" indicates percentage by weight, "part" indicates parts by weight, and "ratio" indicates weight ratio.

[0062] Example 1

[0063] In this embodiment, tantalum powder is used as metal powder and tricalcium phosphate (TCP) is used as ceramic powder to illustrate the technical solution of the present invention.

[0064] A method for preparing a metal / ceramic composite porous implant comprises the following steps:

[0065] S1: Dissolve 4.25 g of acrylamide, 0.425 g of N,N'-methylenebisacrylamide and 0.375 g of sodium polyacrylate in 16 mL of water to obtain solution A; TCP powder is added to solution A and stirring is continued. After the ceramic powder is completely dissolved in solution A without agglomeration, 0.15 g of 30% ammonium persulfate and 0.15 g of 1% N,N,N,N-tetramethylethylenediamine are added and stirred evenly to obtain slurry B; the slurry B is allowed to stand and solidify, and after the slurry solidifies to form a wet blank, it is placed in a vacuum drying oven at a constant temperature of 50°C and dried for 5 hours, and then placed in a degreasing sintering furnace. The degreasing temperature range is set to 30-600°C, and the heating rate is 0.5°C / min. After degreasing is completed, the heating rate is increased to 5°C / min, the sintering temperature is set to 1100°C, and it is kept warm for 4 hours. Sintering treatment is performed to obtain a regenerated ceramic block C, and the regenerated ceramic block C is placed in an ultrasonic cleaner for cleaning for 20 minutes. After cleaning, the regenerated ceramic block C was placed in a vacuum drying oven at a constant temperature of 50°C and dried for 3 hours. After drying, it was crushed, ground and sieved to obtain large-particle regenerated TCP powder with a particle size range of 1 to 120 μm.

[0066] S2: uniformly mixing the regenerated TCP powder, tantalum powder with a particle size of 0.1 to 200 μm, and a binder, sodium alginate, to obtain a mixed slurry; wherein the tantalum powder accounts for 10% of the total volume of the tantalum powder and the regenerated TCP powder.

[0067] S3: Based on the pre-built implant model, the mixed slurry is subjected to direct writing extrusion molding to obtain a metal / ceramic composite implant blank. During the direct writing extrusion molding process, the nozzle moving speed is 1.5mm / s, the plunger feeding speed is 0.2mm / s, and the printing layer height is 0.6mm. Then, the vacuum degree is 1*10 -3 Pa, the metal / ceramic composite implant blank is subjected to vacuum high-temperature sintering treatment, specifically: first, the temperature is increased from room temperature to 350°C at a rate of 5°C / min, and then kept warm for 1 hour; then the temperature is increased to 750°C at a rate of 15°C / min, and kept warm for 2 hours; finally, the temperature is increased to 1500°C at a rate of 50°C / min, and kept warm for 2 hours. After cooling to room temperature with the furnace, the high-temperature sintering treatment is completed to obtain the metal / ceramic composite porous implant.

[0068] Example 2

[0069] The difference between this embodiment and embodiment 1 is that the volume ratio of tantalum powder to recycled TCP powder is 3:7, that is, the tantalum powder accounts for 30% of the total volume of the tantalum powder and recycled TCP powder.

[0070] Example 3

[0071] The difference between this embodiment and embodiment 1 is that the volume ratio of tantalum powder to recycled TCP powder is 4:6, that is, tantalum powder accounts for 40% of the total volume of tantalum powder and recycled TCP powder.

[0072] Example 4

[0073] The difference between this embodiment and embodiment 1 is that the volume ratio of tantalum powder to recycled TCP powder is 5:5, that is, the tantalum powder accounts for 50% of the total volume of the tantalum powder and recycled TCP powder.

[0074] Example 5

[0075] The difference between this embodiment and embodiment 1 is that the metal powder is titanium powder, and the titanium powder accounts for 95% of the total volume of the titanium powder and the recycled TCP powder; and during the vacuum high-temperature sintering process, the final sintering temperature is 1050°C.

[0076] Example 6

[0077] The difference between this embodiment and embodiment 5 is that the titanium powder accounts for 90% of the total volume of the titanium powder and the recycled TCP powder.

[0078] Example 7

[0079] The difference between this embodiment and embodiment 5 is that the titanium powder accounts for 85% of the total volume of the titanium powder and the recycled TCP powder.

[0080] Example 8

[0081] The difference between this embodiment and embodiment 5 is that the titanium powder accounts for 80% of the total volume of the titanium powder and the recycled TCP powder.

[0082] Example 9

[0083] The difference between this embodiment and embodiment 5 is that during the vacuum high-temperature sintering process, the final sintering temperature is 1100°C.

[0084] Example 10

[0085] The difference between this embodiment and embodiment 5 is that during the vacuum high-temperature sintering process, the final sintering temperature is 1150°C.

[0086] Example 11

[0087] The difference between this embodiment and embodiment 6 is that during the vacuum high-temperature sintering process, the final sintering temperature is 1100°C.

[0088] Example 12

[0089] The difference between this embodiment and embodiment 6 is that during the vacuum high-temperature sintering process, the final sintering temperature is 1150°C.

[0090] Example 13

[0091] The difference between this embodiment and embodiment 7 is that during the vacuum high-temperature sintering process, the final sintering temperature is 1100°C.

[0092] Example 14

[0093] The difference between this embodiment and embodiment 7 is that during the vacuum high-temperature sintering process, the final sintering temperature is 1150°C.

[0094] Example 15

[0095] The difference between this embodiment and embodiment 8 is that during the vacuum high-temperature sintering process, the final sintering temperature is 1100°C.

[0096] Example 16

[0097] The difference between this embodiment and embodiment 8 is that during the vacuum high-temperature sintering process, the final sintering temperature is 1150°C.

[0098] Example 17

[0099] The present invention provides a method for preparing a metal / ceramic composite porous implant, comprising the steps of:

[0100] S1: dissolving acrylamide, N,N'-methylenebisacrylamide and sodium polyacrylate in water to obtain solution A; adding hydroxyapatite to solution A and continuing to stir; after the hydroxyapatite is completely dissolved in solution A without agglomeration, adding ammonium persulfate and N,N,N,N-tetramethylethylenediamine and stirring evenly to obtain slurry B; after the slurry B is allowed to stand and solidify, it is dried and degreased at 200°C for 5 hours, and then sintered at 700°C for 6 hours to obtain regenerated ceramic blocks C; the regenerated ceramic blocks C are cleaned, dried, crushed, ground and sieved to obtain regenerated hydroxyapatite with a particle size of 1 to 50 μm;

[0101] The ratio of acrylamide to N,N'-methylenebisacrylamide is 1:10; and the mass ratio of sodium acrylate to ceramic powder is 1:50.

[0102] S2: uniformly mixing the regenerated hydroxyapatite, niobium powder with a particle size of 1 to 100 μm, and a binder to obtain a mixed slurry;

[0103] The niobium powder accounts for 1% of the total volume of the niobium powder and the regenerated hydroxyapatite.

[0104] S3: Based on the pre-built implant model, the mixed slurry is subjected to direct writing extrusion molding. During the direct writing extrusion molding process, the nozzle moving speed is 0.5mm / s, the plunger feeding speed is 0.01mm / s, and the printing layer height is 0.2mm to obtain a metal / ceramic composite implant blank. The metal / ceramic composite implant blank is subjected to vacuum high-temperature sintering treatment, specifically: first, the temperature is increased from room temperature to 150℃ at a rate of 2℃ / min, and then kept warm for 5h; then the temperature is increased to 500℃ at a rate of 2℃ / min and kept warm for 5h; finally, the temperature is increased to 600℃ at a rate of 5℃ / min and kept warm for 5h. After cooling to room temperature with the furnace, the high-temperature sintering treatment is completed; the vacuum degree is 5*10 -2 Pa, to prepare the metal / ceramic composite porous implant.

[0105] The metal / ceramic composite porous implant prepared in this embodiment includes a microscopic pore structure with a pore size of 3 to 45 μm and a macroscopic pore structure with a pore size of 100 to 200 μm. The porosity of the metal / ceramic composite porous implant is 35%.

[0106] Example 18

[0107] The present invention provides a method for preparing a metal / ceramic composite porous implant, comprising the steps of:

[0108] S1: dissolving acrylamide, N,N'-methylenebisacrylamide, and sodium polyacrylate in water to obtain solution A; adding silica powder to solution A and continuing to stir; after the silica is completely dissolved in solution A without agglomeration, adding ammonium persulfate and N,N,N,N-tetramethylethylenediamine and stirring evenly to obtain slurry B; after the slurry B is allowed to stand and solidify, it is dried and degreased at 600°C for 0.5h, and then sintered at 2000°C for 2h to obtain regenerated ceramic blocks C; the regenerated ceramic blocks C are cleaned, dried, crushed, ground, and sieved to obtain regenerated silica powder with a particle size of 50 to 100 μm;

[0109] The ratio of acrylamide to N,N'-methylenebisacrylamide is 10:1; and the mass ratio of sodium acrylate to silica powder is 1:1000.

[0110] S2: uniformly mixing the regenerated silica, magnesium powder with a particle size of 100 to 200 μm, and binder F127 polyether to obtain a mixed slurry;

[0111] The magnesium powder accounts for 99% of the total volume of the magnesium powder and the regenerated silicon dioxide powder.

[0112] S3: Based on the pre-built implant model, the mixed slurry is subjected to direct writing extrusion molding. During the direct writing extrusion molding process, the nozzle moving speed is 45mm / s, the plunger feeding speed is 0.8mm / s, and the printing layer height is 1mm to obtain a metal / ceramic composite implant blank. The metal / ceramic composite implant blank is subjected to vacuum high-temperature sintering treatment, specifically: first, the temperature is increased from room temperature to 400℃ at a rate of 30℃ / min, and then kept warm for 0.5h; then the temperature is increased to 800℃ at a rate of 30℃ / min and kept warm for 0.5h; finally, the temperature is increased to 2000℃ at a rate of 80℃ / min and kept warm for 2h. After cooling to room temperature with the furnace, the high-temperature sintering treatment is completed; the vacuum degree is 1*10 -3 Pa, to prepare the metal / ceramic composite porous implant.

[0113] The metal / ceramic composite porous implant prepared in this embodiment includes a microscopic pore structure with a pore size of 1 to 30 μm and a macroscopic pore structure with a pore size of 800 to 1000 μm. The porosity of the metal / ceramic composite porous implant is 85%.

[0114] Example 19

[0115] The present invention provides a method for preparing a metal / ceramic composite porous implant, comprising the steps of:

[0116] S1: dissolving acrylamide, N,N'-methylenebisacrylamide and sodium polyacrylate in water to obtain solution A; adding magnesium oxide to solution A and continuing to stir; after the magnesium oxide is completely dissolved in solution A without agglomeration, adding ammonium persulfate and N,N,N,N-tetramethylethylenediamine and stirring evenly to obtain slurry B; after the slurry B is allowed to stand and solidify, it is dried and degreased at 300°C for 2 hours, and then sintered at 1200°C for 4 hours to obtain regenerated ceramic blocks C; the regenerated ceramic blocks C are cleaned, dried, crushed, ground and sieved to obtain regenerated magnesium oxide powder with a particle size of 50 to 120 μm;

[0117] The ratio of acrylamide to N,N'-methylenebisacrylamide is 5:7; and the mass ratio of sodium acrylate to ceramic powder is 1:500.

[0118] S2: uniformly mixing the regenerated magnesium oxide powder, zinc powder with a particle size of 100 to 200 μm, and a binder of polyvinyl alcohol to obtain a mixed slurry;

[0119] The zinc powder accounts for 45% of the total volume of the zinc powder and the regenerated magnesium oxide powder.

[0120] S3: Based on the pre-built implant model, the mixed slurry is subjected to direct writing extrusion molding. During the direct writing extrusion molding process, the nozzle moving speed is 20mm / s, the plunger feeding speed is 0.4mm / s, and the printing layer height is 0.5mm to obtain a metal / ceramic composite implant blank. The metal / ceramic composite implant blank is subjected to vacuum high-temperature sintering treatment, specifically: first, the temperature is increased from room temperature to 300℃ at a rate of 20℃ / min, and then kept warm for 2h; then the temperature is increased to 700℃ at a rate of 20℃ / min and kept warm for 2h; finally, the temperature is increased to 1000℃ at a rate of 70℃ / min and kept warm for 3h. After cooling to room temperature with the furnace, the high-temperature sintering treatment is completed; the vacuum degree is 7*10 -3 Pa, to prepare the metal / ceramic composite porous implant.

[0121] The metal / ceramic composite porous implant prepared in this embodiment includes a microscopic pore structure with a pore size of 5 to 20 μm and a macroscopic pore structure with a pore size of 150 to 800 μm. The porosity of the metal / ceramic composite porous implant is 80%.

[0122] Example 20

[0123] The present invention provides a method for preparing a metal / ceramic composite porous implant, comprising the steps of:

[0124] S1: dissolving acrylamide, N,N'-methylenebisacrylamide, and sodium polyacrylate in water to obtain solution A; adding alumina to solution A and continuing to stir; after the alumina is completely dissolved in solution A without agglomeration, adding ammonium persulfate and N,N,N,N-tetramethylethylenediamine and stirring evenly to obtain slurry B; after the slurry B is allowed to stand and solidify, it is dried and degreased at 250°C for 4 hours, and then sintered at 1100°C for 5 hours to obtain regenerated ceramic blocks C; the regenerated ceramic blocks C are cleaned, dried, crushed, ground, and sieved to obtain regenerated alumina powder with a particle size of 60 to 120 μm;

[0125] The ratio of acrylamide to N,N'-methylenebisacrylamide is 4:6; and the mass ratio of sodium acrylate to aluminum oxide is 1:800.

[0126] S2: uniformly mixing the regenerated alumina, tantalum alloy powder with a particle size of 100 to 200 μm, and a binder, carboxymethyl cellulose, to obtain a mixed slurry;

[0127] The tantalum alloy powder accounts for 33% of the total volume of the tantalum alloy powder and the regenerated alumina powder.

[0128] S3: Based on the pre-built implant model, the mixed slurry is subjected to direct writing extrusion molding. During the direct writing extrusion molding process, the nozzle moving speed is 24mm / s, the plunger feeding speed is 0.2mm / s, and the printing layer height is 0.8mm to obtain a metal / ceramic composite implant blank. The metal / ceramic composite implant blank is subjected to vacuum high-temperature sintering treatment, specifically: first, the temperature is increased from room temperature to 300℃ at a rate of 25℃ / min, and then kept warm for 3h; then, the temperature is increased to 600℃ at a rate of 25℃ / min and kept warm for 3h; finally, the temperature is increased to 1700℃ at a rate of 80℃ / min and kept warm for 2.5h. After cooling to room temperature with the furnace, the high-temperature sintering treatment is completed; the vacuum degree is 3*10 -2 Pa, to prepare the metal / ceramic composite porous implant.

[0129] The metal / ceramic composite porous implant prepared in this embodiment includes a microscopic pore structure with a pore size of 30 to 50 μm and a macroscopic pore structure with a pore size of 700 to 1000 μm. The porosity of the metal / ceramic composite porous implant is 67%.

[0130] Figure 1 This is a scanning electron microscope image of the raw material tantalum powder of Example 1 of the present invention. As can be seen from the image, the tantalum powder is irregular in shape.

[0131] Figure 2 This is a particle size distribution diagram of the raw material tantalum powder of Example 1 of the present invention. It can be seen from the figure that the particle size of the tantalum powder is less than 10μm.

[0132] Figure 3 This is the XRD spectrum of the raw material tantalum powder of Example 1 of the present invention. It can be seen from the figure that the tantalum powder is of high purity and contains no other impurities.

[0133] Figure 4 This is a scanning electron microscope image of the raw material TCP powder of Example 1 of the present invention. As can be seen from the figure, the TCP powder is irregular in shape and agglomerated together.

[0134] Figure 5 This is the particle size distribution diagram of the raw material TCP powder of Example 1 of the present invention. It can be seen from the figure that the powder particle size is less than 1 μm.

[0135] Figure 6 This is a macroscopic morphology diagram of the metal / ceramic composite porous implant prepared in Example 1 of the present invention before and after sintering. As can be seen from the figure, a macroscopic pore pattern of hundreds of microns can be formed through the direct writing printing process.

[0136] Figure 7 This is an electron microscope image of the microstructure of the metal / ceramic composite porous implant prepared in Example 2 of the present invention. As can be seen from the image, tantalum powder and TCP are evenly distributed, and microscopic sintering pores are generated.

[0137] Figure 8This is an electron microscope image of the microstructure of the metal / ceramic composite porous implant prepared in Example 3 of the present invention. As can be seen from the image, tantalum powder and TCP are evenly distributed, and microscopic sintering pores are generated.

[0138] Figure 9 This is an electron microscope image of the microstructure of the metal / ceramic composite porous implant prepared in Example 4 of the present invention. As can be seen from the image, tantalum powder and TCP are evenly distributed, and microscopic sintering pores are generated.

[0139] Figure 10 This is an electron micrograph of cell adhesion and growth on the surface of the metal / ceramic composite porous implant prepared in Example 2 of the present invention. As can be seen from the figure, the cells are well attached and stretched, and the composite scaffold can promote cell proliferation.

[0140] Figure 11 This is an electron micrograph of cell adhesion and growth on the surface of the metal / ceramic composite porous implant prepared in Example 3 of the present invention. As can be seen from the figure, the cells are well attached and stretched, and the composite scaffold can promote cell proliferation.

[0141] Figure 12 This is an electron micrograph of cell adhesion and growth on the surface of the metal / ceramic composite porous implant prepared in Example 4 of the present invention. As can be seen from the figure, the cells are well attached and stretched, and the composite scaffold can promote cell proliferation.

[0142] Figure 13 is the porosity of the metal / ceramic composite porous implants prepared in Examples 5 to 16 of the present invention. As can be seen from the figure, the porosity of the composite porous implants is between 72% and 79%.

[0143] Figure 14 This is a microscopic morphology of the Ti / TCP composite scaffold prepared in the present invention. Microscopic pores ranging from several micrometers to tens of micrometers can be observed between the ceramic particles and the titanium powder particles through sintering.

[0144] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a metal / ceramic composite porous implant, characterized in that: The following steps are included: S1: dissolving acrylamide, N,N'-methylenebisacrylamide, and sodium polyacrylate in water to obtain solution A; adding ceramic powder to solution A and continuing to stir; after the ceramic powder is completely dissolved in solution A without agglomeration, adding ammonium persulfate and N,N,N,N-tetramethylethylenediamine and stirring evenly to obtain slurry B; allowing the slurry B to stand and solidify, drying, degreasing, and then sintering to obtain regenerated ceramic blocks C; washing, drying, crushing, grinding, and sieving the regenerated ceramic blocks C to obtain regenerated ceramic powder; S2: uniformly mixing the recycled ceramic powder, metal powder and binder to obtain a mixed slurry; S3: Based on a pre-constructed implant model, the mixed slurry is subjected to direct extrusion molding to obtain a metal / ceramic composite implant blank, and the metal / ceramic composite implant blank is subjected to vacuum high-temperature sintering treatment to obtain the metal / ceramic composite porous implant.

2. The method for preparing a metal / ceramic composite porous implant according to claim 1, characterized in that: In step S1, the mass ratio of acrylamide to N,N'-methylenebisacrylamide is (1-10):(10-1); the mass ratio of sodium acrylate to ceramic powder is 1:(50-1000).

3. The method for preparing a metal / ceramic composite porous implant according to claim 1, characterized in that: In step S1, the degreasing treatment is performed at a temperature of 200 to 600° C. for 0.5 to 5 hours.

4. The method for preparing a metal / ceramic composite porous implant according to claim 1, characterized in that: In step S1, the sintering temperature is 700-2000° C. and the sintering time is 2-6 hours.

5. The method for preparing a metal / ceramic composite porous implant according to claim 1, characterized in that: The particle size of the recycled ceramic powder is 0.1 to 120 μm; the particle size of the metal powder is 0.1 to 200 μm.

6. The method for preparing a metal / ceramic composite porous implant according to claim 1, characterized in that: The ceramic powder is at least one of hydroxyapatite, tricalcium phosphate, silicon dioxide, magnesium oxide and aluminum oxide; the metal powder is at least one of tantalum powder, titanium powder, niobium powder, beryllium powder, magnesium powder, zinc powder, tantalum alloy, titanium alloy, niobium alloy, beryllium alloy, magnesium alloy and zinc alloy.

7. The method for preparing a metal / ceramic composite porous implant according to claim 1, characterized in that: The metal powder accounts for 1% to 99% of the total volume of the metal powder and the recycled ceramic powder.

8. The method for preparing a metal / ceramic composite porous implant according to claim 1, characterized in that: In step S3, during the direct writing extrusion forming process, the nozzle moving speed is 0.5-45 mm / s, the plunger feeding speed is 0.01-0.8 mm / s, and the printing layer height is 0.2-1 mm.

9. The method for preparing a metal / ceramic composite porous implant according to claim 1, characterized in that: In step S3, the vacuum high-temperature sintering process is specifically as follows: first, the temperature is raised from room temperature to 150-400°C at a rate of 2-30°C / min, and then kept at this temperature for 0.5-5h; then, the temperature is raised to 500-800°C at a rate of 2-30°C / min, and kept at this temperature for 0.5-5h; finally, the temperature is raised to 600-2000°C at a rate of 5-80°C / min, and kept at this temperature for 2-5h, and then the high-temperature sintering process is completed after the furnace is cooled to room temperature; the vacuum degree is 5*10 -2 ~1*10 -3 Pa.

10. A metal / ceramic composite porous implant, characterized in that: The metal / ceramic composite porous implant is prepared by the method according to any one of claims 1 to 9; the metal / ceramic composite porous implant comprises a microporous structure with a pore size of 1 to 50 μm and a macroporous structure with a pore size of 100 to 1000 μm, and the porosity of the metal / ceramic composite porous implant is 30% to 90%.

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