CN108393493B - Preparation method of high-strength degradable nano medical porous titanium-based composite material - Google Patents

Abstract

The invention relates to a preparation method of a degradable nano titanium-based composite material with human affinity and mechanical properties close to those of human bones, in particular to a novel porous titanium-based composite material which is applied to the field of medical implantation. The porous titanium-based composite material with the nanocrystalline grain structure provided by the invention takes titanium, magnesium, silicon, vanadium and silver as initial components, and the composition of the porous titanium-based composite material can be represented by aTi-bMg-cSi-dV-eAg-f (TiC-SiC-ZrC), wherein a=40, b=10, c=45, d= 3,e =1.5, f=0.5 and a+b+c+d+e+f=100. The high-strength nano Ti-3V-1.5Ag-0.5 (TiC-SiC-ZrC) titanium-based porous composite material is obtained by a chemical removal method, and the obtained porous nano material has mechanical properties similar to that of human bones, reliable mechanical hardness and strength and good toughness. And the material has good degradability, so that the material has potential application value and can be used in the field of medical implantation.

Description

Preparation method of high-strength degradable nano-medical porous titanium-based composite material

Technical field

The invention relates to a method for preparing a degradable nano-titanium-based composite material with human body affinity and mechanical properties close to human bone. Specifically, it is a new type of porous titanium-based composite material used in the field of medical implantation.

Background technique

The metals and alloys currently used in medicine mainly include medical stainless steel, medical cobalt-based alloys, medical titanium and its alloys, medical magnesium alloys and other metals and alloys. Traditional medical metals and alloys are prone to corrosion, and dissolved ions may induce diseases and cause cell death. And tissue necrosis, poor mechanical properties, no biological activity, poor wear resistance, fatigue and fracture toughness are not ideal and other shortcomings. And the stiffness of traditional implants is too high. Due to this stress shielding, large and rigid femoral prostheses are not recommended for patients with low bone density, which involves bone resorption and bone loss caused by stress shielding. In clinical trials, more than 12 percent of patients experienced moderate or severe bone loss within two years of implants. Traditional medical materials have poor affinity and degradability to the human body, and bone tissue cannot grow inward and heal with human bones.

Contents of the invention

The purpose of the patent of this invention is to address the shortcomings of alloys currently used in the medical field. In order to reduce the mismatch between the implant and the surrounding bone tissue and achieve optimized loading of the stiffness of the artificial implant transferred to the adjacent bone, a method is provided Nanomaterials with good biological activity, degradability, and mechanical properties close to human bone with a highly open porous structure.

The present invention is realized through the following technical solutions:

The porous titanium-based composite material with nano-grain structure provided by the invention uses titanium, magnesium, silicon, vanadium and silver as initial components, and its composition can be aTi-bMg-cSi-dV-eAg-f(TiC-SiC-ZrC ) represents, where a=40, b=10, c=45, d=3, e=1.5, f=0.5 and a+b+c+d+e+f=100; high strength is finally obtained by chemical removal method Nano-Ti-3V-1.5Ag-0.5 (TiC-SiC-ZrC) titanium-based porous composite material. The obtained porous nanomaterial has mechanical properties similar to human bones, with reliable mechanical hardness and strength and good toughness. And it has good degradability. Therefore, the material of the present invention has potential application value and can be used in the field of medical implantation. The advantage and special feature of the porous titanium-based composite material with nano-grain structure is that it uses titanium, magnesium, silicon, vanadium, silver and other components as its basic components. The human body needs trace elements vanadium and magnesium, of which magnesium has Good degradability, it can automatically and slowly decompose after being implanted in the human body. Silicon can form a highly open porous structure after being etched with alkali in the later stage, and the presence of titanium gives it reliable hardness conditions, and porous titanium can make it It has mechanical properties similar to those of human bones. The existence of pores provides the possibility for the ingrowth of bone tissue. Vanadium can be well combined with titanium, giving the material good overall properties. The addition of silver metal gives the material broad-spectrum antibacterial properties and improves the material's medical function. The granular material is prepared and then bonded with acetone to directly press it into a blank, which avoids the toxic substances produced by the traditional metal sintering process, and can be repeatedly extruded through the cross-shaped mold channel without removing the parts to form a nano-grain structure. Titanium-based composite materials, the formed nanomaterials are corroded in alkali to form nanomaterials with a highly open porous structure. After the materials are implanted into the human body, they can slowly degrade by themselves, providing opportunities for the ingrowth of bone tissue and implantation into bones and the human body. Possibility of bone tissue healing. The invention provides a method for preparing high-strength porous nano-medical degradable titanium-based composite materials, which includes the following steps:

(1) Ingredients for billet making: Take Cp Ti powder, Mg particles (purity 99.6%), Si particles (purity 99.9%), V particles (purity 99.9%), Ag particles (purity 99.9%) and TiC-SiC-ZrC For whisker particles, the powder blend was weighed in an argon-filled glovebox and then mixed with 1% by weight isopropyl alcohol and stirred for 3 minutes. Subsequently, the element mixture slurry is taken out of the glove box in the sealed container and poured into the press mold inlet channel, while the outlet channel is blocked by a back-pressure punch, the mixture is cold pressed at 50MPa, and dried at room temperature 5 minutes to allow the isopropyl alcohol to evaporate and the adhesion between particles to disappear. Finally, it was processed into a rod-shaped sample of D10mm×68mm.

(2) Obtain nanostructure: Put the sample into the bag. The outer dimensions of the bag are D12mm×70mm and the inner cavity is D10mm×68mm. Repeated extrusion can be achieved through the cross-shaped mold channel without removing the parts, and the nanocrystalline structure can be obtained. For titanium-based composite materials with a granular structure, the extrusion parameters of the cross-shaped die channel are: the punch extrusion speed is 1mm/s. Sufficient deformation can be accumulated to obtain high-strength nanomaterials by rotating the cross-shaped die 4 times.

(3) Form a material with a highly open porous structure: The rod-shaped nanomaterials produced by the cross-shaped mold are soaked in a 5M sodium hydroxide (NaOH) aqueous solution at 60°C for 12 hours to remove Si, washed and ultrasonically cleaned with distilled warm water. Reaction for Si removal: Si _(s) +2NaOH _(aq) +H ₂ O _(aq) =Na ₂ SiO _3(aq) +2H _2(g)

The porous Ti/Mg composite material with Si material removed was immersed in 5L hydrochloric acid (HCl) at room temperature for 6 hours, then washed with distilled warm water and dried in the air for 24 hours, finally obtaining a porous Ti-based composite material with a porosity of 55%.

Mg _(s) +2HCl _(aq) =MgCl2 _(aq) +2H _2(g)

The preparation process of titanium carbide-silicon carbide-zirconium carbide whisker particles in the above step (1) is: the chemical composition and weight percentage of the titanium oxide-silicon carbide-zirconium carbide whisker precursor material are: ZrO ₂ : 25.4 to 28.2%, Ti: 19.6-19.8%, _SiO2 : 25.4-28.2%, C: 20.2-22.6%, Mn: 0.1-0.9%, NaCl: 1.0-8.1%. The precursor composite powder prepared in proportion to generate titanium carbide-silicon carbide-zirconium carbide whiskers is added to anhydrous ethanol in a ball mill for mechanized ball milling for 48 hours to obtain an ultra-fine precursor composite powder with a grain size of 200-600nm. The powder is put into a graphite container and synthesized under the protection of argon atmosphere and a temperature of 1550°C-1800°C for 90min-180min.

SiO ₂ +2C=(heating)Si+2CO↑

Si+C=(heating)SiC

ZrO ₂ +3C=(heating)ZrC+2CO↑

Ti+C=(heating)TiC

The invention adopts titanium carbide-silicon carbide-zirconium carbide reinforced degradable nano-medical porous titanium-based composite material, which is characterized in that: the material forms directional arrangement of titanium carbide-silicon carbide-zirconium carbide whiskers and titanium along the extrusion streamlines. It is composed of matrix composite material and the whisker diameter is 200-800nm.

The invention provides a method for preparing high-strength nano-medical degradable titanium-based composite materials. Compared with existing medical alloys, its advantages are:

1. The first is the innovation in the formula: titanium, magnesium, silicon, and vanadium are mixed in a certain proportion. Among them, CP Ti is chosen instead of the commonly used titanium-based composite materials because it will not release XIC alloy elements in the body, and titanium is An element that can ionize cells and regulate human body current by emitting consistent wavelengths, thereby producing beneficial physiological effects on the human body. Titanium has excellent mechanical properties, corrosion resistance and biocompatibility, and can provide sufficient mechanical strength. Forming a highly open porous structure, the material has mechanical properties similar to human bones; Mg and V are essential trace elements for the human body, and vanadium can be well combined with titanium; Mg powder and Si powder are used as space materials, whether magnesium Neither silicon nor silicon will cause cytotoxicity, and magnesium has the advantages of mildness, absorbability, and good biocompatibility. Silicon can be corroded away by alkali later to form a material with a highly open porous structure. The degradation behavior of magnesium makes it a biological Degradable implant materials can self-degrade in the human body after implantation, providing the possibility for bone tissue to grow in and the implanted bone to heal with human bone tissue.

2. The second is the innovation of the production process:

(a) The granular materials are uniformly prepared and bonded with isopropyl alcohol and directly pressed to form a blank, which overcomes the shortcoming that traditional metal smelting and sintering may produce toxic substances.

(b) Using a cross-shaped mold channel, repeated extrusion can be completed without removing the parts to cause severe plastic deformation of the sample to obtain a titanium-based composite material with a nano-grain structure. The obtained nanomaterials have the advantages of high strength, good toughness, good mechanical properties, good fatigue resistance, corrosion resistance, and degradability.

3. Innovation in the formation of material morphology and structure: adding alkali to the processed nanomaterials to corrode silicon, and magnesium can later self-degrade in the human body to form nanomaterials with a highly open porous structure, making the materials have properties similar to those of the human body. Mechanical properties, and magnesium can slowly degrade by itself after being implanted in the human body, providing the possibility for the ingrowth of the original bone tissue of the body and promoting the healing of the implanted material and the original bone tissue of the body.

4. The preparation method required by the present invention has a simple process, is easy to realize large-scale automated production, and can be used in the field of medical implantation.

Picture description:

Specific embodiments of the present invention are described in detail below with reference to the drawings and examples.

Figure 1 is a schematic diagram of granular materials being uniformly mixed and bonded and then pressed through a press;

Figure 2 is a schematic diagram of the formed rod specimen;

Figure 3 is a schematic diagram of preparing a titanium-based composite material with a nano-grain structure through repeated extrusion deformation through a cross-shaped die channel in a specific embodiment of the present invention;

Figure 4 is a schematic diagram of treating rod-shaped materials with alkali to form porous materials;

The markings in the above figure are:

Figure 1 is a schematic diagram of uniformly mixing granular materials and pressing and molding through strong pressure. 1. Press upper cover 2. Press cavity 3. Press lower cover 4. Rod sample extrusion channel.

Figure 2 is a schematic diagram of the formed rod-shaped sample: 1. Covering cover, 2. Covering, 3. Sample.

Figure 3 is a schematic device diagram for preparing titanium-based composite materials with nano-grain structure through repeated extrusion deformation through cross-shaped die channels in a specific embodiment of the present invention. 1. punch, 2. extruded part blank, 3. rotating concave Mold, 4. Prestressed clamp, 5. Ejector, 6. Back pressure ejector, 7. Prestressed clamp base.

Figure 4 is a schematic diagram of treating rod-shaped materials with alkali to form porous materials: 1. Beaker 2. NaOH solution 3. Rod-shaped nanomaterials.

Detailed ways:

Example 1: Preparation method of a high-strength nano-medical porous titanium-based composite material

The molar ratio of Ti powder, Mg particles (purity 99.6%), Si particles (purity 99.9%), V particles, Ag particles and TiC-SiC-ZrC whisker particles is 40:10:45:3:1.5: 0.5 After uniform mixing and preparation, it is bound with isopropyl alcohol, then extruded through the press die on a press, and dried at room temperature for 5 minutes to allow the isopropyl alcohol to evaporate and the adhesion between particles disappear, finally forming D10mm×68mm rod-shaped sample; put the rod-shaped sample into the bag and rotate it repeatedly through the cross-shaped channel and squeeze it 4 times to produce severe plastic deformation to obtain a titanium-based composite material with nano-grain structure. The cross-shaped mold channel is produced The rod-shaped nanomaterials were soaked in 5L sodium hydroxide (NaOH) aqueous solution at 60°C for 12 hours to remove Si. Then, the porous Ti/Mg composite material with Si removed was immersed in 5L hydrochloric acid (HCl) at room temperature for 6 hours. , washed and ultrasonically cleaned with distilled warm water, then washed with distilled warm water and dried in the air for 24 hours, and finally a porous Ti-based composite material with a porosity of 55% was obtained. The Ti-10Mg-45Si-3V-1.5Ag-0.5 (TiC-SiC-ZrC) titanium-based composite material with nano-grain structure provided by the present invention can be prepared by using simple metal pressure processing equipment, and then obtain high-quality materials through chemical removal methods. Strength Nano-Ti-3V-1.5Ag-0.5 (TiC-SiC-ZrC) titanium-based porous composite material. The obtained porous nanomaterial has mechanical properties similar to human bones, with reliable mechanical hardness and strength and good toughness. And it has good degradability. Therefore, the material of the present invention has potential application value and can be used in the field of medical implantation.

Claims (1)

1. A method for preparing high-strength medical nanoporous titanium-based composite materials, which is characterized by: using titanium, magnesium, silicon, vanadium, silver, TiC-SiC-ZrC whisker particles as basic materials, and granular The materials are mixed and prepared according to a certain proportion and are bonded with isopropyl alcohol and then directly pressed into powder to form a blank. The blank passes through the cross-shaped mold channel and undergoes repeated extrusion and severe plastic deformation without removing the parts to obtain a high-strength material with a nano-grain structure. ;Then the nanomaterial is placed in an alkali to etch away the silicon to form a nanomaterial with a highly open porous structure. The preparation steps are as follows: (a) Metal particle components: titanium, magnesium, silicon, vanadium, and silver are the initial components, and their composition can be represented by aTi-bMg-cSi-dV-eAg-f (TiC-SiC-ZrC), where the molar ratio a =40, b=10, c=45, d=3, e=1.5, f=0.5 and a+b+c+d+e+f=100 (b) Prepare the metal particle components provided in step (a) evenly in proportion, weigh the powder blend in an argon-filled glove box, and then mix it with 1% isopropyl alcohol by weight and stir for 3 minutes; subsequently, take the mixture slurry out of the glove box in the sealed container and pour it into the press mold inlet channel, while blocking the outlet channel through a back-pressure punch, cold-press the mixture at 50MPa, and dry at room temperature For 5 minutes, the isopropyl alcohol evaporates and the adhesion between particles disappears; finally processed into a rod-shaped sample of D10mm×68mm; (c) The rod-shaped sample formed by compression of the metal particle components provided in step (b) can complete repeated severe plastic deformation through the cross-shaped mold channel without removing the parts to obtain a high-strength titanium-based composite material with a nano-grain structure. ; The parameters of the channel repeated extrusion processing are: the extrusion speed of the punch is 1mm/s, and sufficient deformation can be accumulated to obtain high-strength nanomaterials by rotating the cross-shaped die 4 times; (d) Obtain a high-strength titanium-based composite material with a nano-grain structure by repeated severe plastic deformation provided in step (c), soak in 5L sodium hydroxide (NaOH) aqueous solution at 60°C for 12 hours to remove Si, and then, The porous titanium-based composite material with Si material removed was immersed in 5L hydrochloric acid (HCl) at room temperature for 6 hours, washed and ultrasonically cleaned with distilled warm water, then washed with distilled warm water and dried in the air for 24 hours, finally obtaining a porosity of 55% Porous Ti-based composite materials.