阅读说明：本技术 一种生物医用植入锆合金及制备方法 (Biomedical implanted zirconium alloy and preparation method thereof ) 是由 陈锋 罗聪 武祥为 于 2020-05-20 设计创作，主要内容包括：本发明涉及一种生物医用植入锆合金及制备方法,所述合金的组份及重量百分比为：Nb：30-44wt％；Ti：5-10wt％；O：0.10-0.15wt％；余量为Zr。合金制备的具体步骤是：采用高真空非自耗电弧炉熔炼获得成分均匀的合金铸锭,经热锻成棒材后在900-1000℃固溶处理,保温时间为30-60min,随后水冷至室温,得到单一β-Zr组织。与传统的生物医用植入材料Ti-6Al-4V合金相比,本发明合金具有高强度、低弹性模量、高塑性和高耐蚀性等优点,生物相容性和力学相容性更优异,十分适合制作需大塑性变形加工的高性能生物医用植入部件。(The invention relates to a biomedical implanted zirconium alloy and a preparation method thereof, wherein the alloy comprises the following components in percentage by weight: nb: 30-44 wt%; ti: 5-10 wt%; o: 0.10-0.15 wt%; the balance being Zr. The preparation method of the alloy comprises the following specific steps: smelting by adopting a high-vacuum non-consumable arc furnace to obtain an alloy ingot with uniform components, carrying out hot forging to obtain a bar, carrying out solution treatment at the temperature of 900-1000 ℃, keeping the temperature for 30-60min, and then carrying out water cooling to room temperature to obtain a single beta-Zr structure. Compared with the traditional biomedical implant material Ti-6Al-4V alloy, the alloy has the advantages of high strength, low elastic modulus, high plasticity, high corrosion resistance and the like, has more excellent biocompatibility and mechanical compatibility, and is very suitable for manufacturing high-performance biomedical implant parts needing large plastic deformation processing.)

1. The biomedical implanted zirconium alloy is characterized by comprising the following components in percentage by weight:

Nb：30-44wt％；

Ti：5-10wt％；

O：0.10-0.15wt％；

the balance being Zr.

2. The biomedical implant zirconium alloy of claim 1, wherein the open circuit potential of the zirconium alloy in ringer's solution is: -197 to-235 mV; corrosion potential: 206 to-255 mV; corrosion current: 11.6 to 51.6nA/cm²(ii) a Passivation current: 0.83 to 1.76 mu A/cm²。

3. The biomedical implanted zirconium alloy according to claim 2, wherein the ringer solution comprises the following components in percentage by weight: 9g/L of sodium chloride, 0.42g/L of potassium chloride, 0.25g/L of calcium chloride and the balance of deionized water; the pH value is 7.2 +/-0.1, and the temperature is controlled at 25 +/-1 ℃.

4. The biomedical implant zirconium alloy of claim 1, wherein the zirconium alloy has a compressive yield strength of: 1083-1213 MPa; modulus of compression elasticity: 70-75 GPa; compression ratio: is more than 85.1 percent.

5. A method of preparing a biomedical implanting zirconium alloy according to claim 1, comprising the steps of:

the first step is as follows: based on the zirconium alloy composition, Zr, Nb, Ti, TiO₂Preparing raw materials according to a proportion;

the second step is that: repeatedly smelting the prepared raw materials in a magnetic stirring high-vacuum non-consumable electric arc furnace to obtain an ingot with uniform components;

the third step: and (3) hot forging the cast ingot into a bar, putting the bar into water for quenching and cooling after solution treatment to obtain the biomedical implanted zirconium alloy with the single beta-Zr structure.

6. The method for preparing the biomedical implanting zirconium alloy according to claim 5, wherein the Zr, the Nb, the Ti and the TiO are selected from the group consisting of₂The purity of the raw materials is more than 99.9 wt%.

7. The method as claimed in claim 5, wherein the hot forging is carried out at a heating temperature of 600-700 ℃ and a deformation amount of 60-80% in air.

8. The method for preparing the biomedical implanting zirconium alloy as claimed in claim 5, wherein the solution treatment is carried out at a heating temperature of 900-1000 ℃ and the heat preservation time of 30-60 min.

Technical Field

The invention belongs to the technical field of new material design and preparation, and relates to a biomedical implanted zirconium alloy with high strength, low elastic modulus, high plasticity and high corrosion resistance and a preparation method thereof.

Background

In recent years, with the development of society and the improvement of living standard of human beings, the demand of safe and reliable biomedical implants is increasing. At present, titanium and its alloy are the first choice materials for repairing and replacing human hard tissues such as artificial joints and dental implants due to excellent mechanical properties and high corrosion resistance in human body fluid environment. The common titanium-based implant material has Ti-6Al-4V, the tensile strength of which is 895MPa-930MPa, the elongation rate of which is about 10 percent, and is the implant material which is most widely applied at present, but the following problems exist: (1) the alloy contains V, Al element harmful to human body, especially V has cytotoxicity, and has potential safety hazard in long-term use. (2) The elastic modulus (110GPa) of the alloy is far higher than the modulus (10-30GPa) of human skeleton, the serious mismatching of the elastic modulus causes the interface of the implant and the skeleton to generate stress shielding effect, and the long-term use causes the implant to become sterile and loose, thereby shortening the service life. (3) The corrosion resistance of the alloy in a body fluid environment is obviously lower than that of a titanium alloy containing elements such as Nb and Zr (such as Dailaidan, novel electrochemical corrosion behaviors of medical Ti-35Nb-4Sn-6Mo-9Zr and Ti-35Nb-1.3Mo-3.7Zr alloy in ringer solution, rare metal materials and engineering, 2014,43:91-95), and the corrosion resistance of the alloy is further improved to prolong the service life of an implant. (4) The shape of implants such as artificial joints is complex, and large plastic deformation processing is usually needed, but the plastic deformation capacity of Ti-6Al-4V is still insufficient, and the processing efficiency and the quality of products are influenced.

Elements with good biocompatibility with the human body include Zr, Ti, Nb, Ta, Mo, Sn, etc., wherein Zr is the most excellent in performance. Relevant studies have shown that (Kuroda D, Niinomi M, Morinaga M, et al, Design and mechanical properties of new β type titanium alloys for implant materials, Mater Sci Eng A,1998,243(1-2):244-249), Zr is superior to Ti in terms of relative cell proliferation rate, and that the biocompatibility of Nb, Ti, Zr gradually increases, indicating that Zr is more favorable for the adhesion growth of bone cells.

At present, some biomedical zirconium-based alloys with low elastic modulus (good mechanical compatibility) are prepared by adding biocompatible elements such as Nb and Ti. For example, the Zr4Ti13Nb alloy developed by Pengfei Chui (Pengfei Chui. near b-type Zr-Nb-Ti biomedical alloys with high strength and low modulus, Vacuum,2017,143:54-58), has yield strength of 774MPa, elastic modulus of 27MPa, compressibility of 45.8%, low strength, and unobtrusive plasticity. Zr32Ti38Ta8Nb alloy (Sertan Ozan, Jixing Lin, New Ti-Ta-Zr-Nb alloys with ultra high strength for porous orthogonal indicators applications, Journal of the Mechanical Biomedical Materials,2017,75:119 Materials 127) developed by Sertan Ozan, the yield strength of the compression test is 1317MPa, the elastic modulus is 73MPa, the compression ratio is 22-36%, and the plasticity is obviously lower; in addition, the alloy has high cost due to the high content of the noble element Ta.

The corrosion resistance of an alloy is generally evaluated electrochemically, and among its relevant parameters, the open circuit potential Φ_ocpAnd corrosion potential phi_corrThe higher the corrosion current I_corrAnd a passivation current I_passLower means higher corrosion resistance of the alloy. Currently, the corrosion resistance of biomedical zirconium-based alloys is rarely studied, and mainly research is being conducted on titanium alloys added with Zr and Nb. Zr22Ti18Nb alloy from Xuehui Yan (Xuehui Yan, Yong Zhang. A body-center d cubic Zr)₅₀Ti₃₅Nb₁₅medium-even alloy with unique properties, script Materialia,2020,178: 329) with an annealed structure of β phase, phi_corrIs-422 mV, I_corrIs 310nA/cm²，I_passIs 0.336 mu A/cm²The corrosion resistance is generally equivalent to that of pure titanium and Ti-6Al-4V alloy; the tensile strength is 703MPa, the yield strength is 657MPa, the elastic modulus is 62GPa, the elongation is 21.9 percent, and the alloy strength is obviously lower. Ti13Nb13Zr alloy (Nilson T.C. Oliveira, Elivelton A.Ferreira, Corroson resistance of inorganic oxides on the Ti-50 Zr and Ti-13 Nb-13 Zr alloys, Electrochimica Acta,2006,51: 2068) developed by Nilson T.C. with 870 ℃ fixingDissolving and aging at 500 ℃ to obtain α + β two-phase structure phi_ocpIs-296 mV,. phi.,_corrthe alloy is-825 mV, the corrosion resistance is not as good as that of pure titanium and Ti-6Al-4V alloy in view of data, the tensile strength is 851MPa, the yield strength is 739MPa, the elastic modulus is 80GPa, the elongation is 14%, the alloy strength is low and the elastic modulus is high, the Ti35Nb9Zr6Mo4Sn alloy developed by Daizhiya (Daishilan, the design and the organizational performance research of a novel medical β titanium alloy, the doctor academic paper of southeast university, 2014,44-45 and 85-90) is a β phase in solid solution, and phi is phi_corrIs-230 mV, I_corr251nA/cm²Compared with Ti-6Al-4V which is synchronously tested, the corrosion resistance has certain advantages; the tensile strength was 814MPa, the yield strength was 787MPa, the elastic modulus was 66GPa, and the elongation was 11%, indicating that the strength was low and the elongation was no better than Ti-6 Al-4V.

From the above, it can be seen that the current research on implanting zirconium alloy has difficulty in matching high strength, low modulus, high corrosion resistance and high plasticity.

The implant needs to be in service in a human body for at least 20 years, the high strength and high plasticity (beneficial to improving fatigue strength) and excellent corrosion resistance are beneficial to prolonging the service life of the implant, and on the other hand, the shape of the implant such as an artificial joint is complex, and large plastic deformation is generally needed for processing and preparation (rolling, bending, extruding, cold heading, thread rolling and the like). Therefore, based on the defects of the existing Ti-6Al-4V alloy, the research and development of a novel medical implantation alloy material which has more excellent biocompatibility and mechanical compatibility, high strength, low elastic modulus, high plasticity and high corrosion resistance has important application value.

Disclosure of Invention

The technical problem is as follows: the invention aims to provide a biomedical implanting zirconium alloy material with high strength, low elastic modulus, high plasticity and high corrosion resistance and a preparation method thereof, wherein the alloy has excellent biocompatibility and mechanical compatibility and is very suitable for manufacturing high-performance biomedical implanting parts needing large plastic deformation processing.

The technical scheme is as follows: the invention relates to a biomedical implanted zirconium alloy and a preparation method thereof, wherein the biomedical implanted zirconium alloy comprises the following components in percentage by weight:

Nb：30-44wt％；

Ti：5-10wt％；

O：0.10-0.15wt％；

the balance being Zr.

Wherein the content of the first and second substances,

open circuit potential of zirconium alloy in ringer's solution: -197 to-235 mV; corrosion potential: 206 to-255 mV; corrosion current: 11.6 to 51.6nA/cm²(ii) a Passivation current: 0.83 to 1.76 mu A/cm²。

The ratio of the ringer solution is as follows: 9g/L of sodium chloride, 0.42g/L of potassium chloride, 0.25g/L of calcium chloride and the balance of deionized water; the pH value is 7.2 +/-0.1, and the temperature is controlled at 25 +/-1 ℃.

Compressive yield strength of zirconium alloy: 1083-1213 MPa; modulus of compression elasticity: 70-75 GPa; compression ratio: is more than 85.1 percent.

The preparation method of the biomedical implanted zirconium alloy comprises the following steps:

the first step is as follows: based on the zirconium alloy composition, Zr, Nb, Ti, TiO₂Preparing raw materials according to a proportion;

the second step is that: repeatedly smelting the prepared raw materials in a magnetic stirring high-vacuum non-consumable electric arc furnace to obtain an ingot with uniform components;

the third step: and (3) hot forging the cast ingot into a bar, putting the bar into water for quenching and cooling after solution treatment to obtain the biomedical implanted zirconium alloy with the single beta-Zr structure.

The Zr, Nb, Ti and TiO₂The purity of the raw materials is more than 99.9 wt%.

The hot forging is carried out in the air at the heating temperature of 600-700 ℃ and the deformation amount of 60-80%.

The solution treatment is carried out at the heating temperature of 900-1000 ℃ and the heat preservation time of 30-60 min.

Has the advantages that:

1. by reasonably combining the Zr content, the Nb content and the Ti content and adopting high-temperature solid solution and quenching treatment, the alloy is ensured to be a single beta phase, and the corrosion of a micro battery caused by the potential difference of an electrode due to the precipitation of a second phase is avoided. The high-temperature solution treatment can also improve the uniformity of beta structure, eliminate defects and further ensure that the alloy has excellent plastic processing performance.

2. The influence of the Nb and Ti contents on the elastic modulus of the beta zirconium alloy and the influence of the Nb and Ti contents on the corrosion resistance of the zirconium alloy are comprehensively considered, and the reasonable combination of the Zr, Nb and Ti contents is determined, so that the alloy has low elastic modulus and high corrosion resistance.

3. In zirconium alloys, oxygen, as an interstitial element, can distort the lattice of beta zirconium and also refine the beta structure. The addition of a small amount of oxygen can significantly improve the strength of the alloy, and has little influence on the elastic modulus and plasticity.

4. Compared with the most widely used Ti-6Al-4V alloy, the alloy has obviously better biocompatibility, mechanical compatibility and corrosion resistance, has the characteristics of high strength (the compressive yield strength is 1083-1213 MPa), low elastic modulus (70-75 GPa) and ultrahigh plasticity (the compression ratio is more than 85.1 percent), and is very suitable for manufacturing high-performance biomedical implant parts needing large plastic deformation processing.

Drawings

FIG. 1 is a plot (local) of compressive stress-strain for a sample of a Zr40Nb5Ti0.1O alloy, showing a compressive yield strength of 1175 MPa.

FIG. 2 is a photograph showing the comparison of the Zr40Nb5Ti0.1O alloy samples before and after compression, and it can be seen that the compressibility can reach 90% or more.

FIG. 3 shows the open circuit potential of Zr40Nb5Ti0.1O alloy, pure titanium and Ti-6Al-4V alloy in ringer's solution.

FIG. 4 is a polarization curve of Zr40Nb5Ti0.1O alloy, pure titanium and Ti-6Al-4V alloy in ringer solution.

FIG. 5a and FIG. 5b are respectively a comparison of the surface morphology of Zr40Nb5Ti0.1O alloy and pure titanium after corrosion in ringer solution, which shows that the corrosion resistance of the alloy of the invention is obviously superior to that of pure titanium.

Detailed Description

The invention designs and prepares the medical implanted zirconium alloy with high strength, low elastic modulus, high plasticity and high corrosion resistance based on the following thought:

Nb：30-44wt％；

Ti：5-10wt％；

O：0.10-0.15wt％；

the balance being Zr.

O content in the O alloy. TiO 2₂Is a raw material, wherein 40 wt% of the raw material is O, 60 wt% of the raw material is Ti, O, Ti elements of the raw material enter the alloy during smelting, and the calculation is good during batching.

(1) Since the elastic modulus of beta-zirconium is low and that of alpha-zirconium is high, a proper amount of beta-stabilizing element Nb must be added to ensure that the zirconium alloy is a single beta phase. The single beta phase also has the advantages of high plasticity (the beta phase has 12 slip systems, and the alpha phase has only 3 slip systems), better corrosion resistance (preventing microscopic battery corrosion caused by an alpha + beta double-phase structure), and the like.

(2) Research shows that Nb is formed in the Zr-Nb-Ti alloy₂O₅、ZrO₂、TiO₂On the other hand, the research aiming at the low elastic modulus β titanium alloy shows that the β titanium alloy has the lowest elastic modulus when in metastable β stability, so that the addition amount of the β stabilizing element Nb in the zirconium alloy cannot be too high by taking the research results thereof as a reference, and the alloy has both low elastic modulus and high corrosion resistance by reasonably combining the contents of Zr, Nb and Ti.

(3) Oxygen is an essential element for human body, and has good biocompatibility. The addition of a small amount of oxygen in the zirconium alloy can cause the beta zirconium to generate lattice distortion and refine grain structure so as to obviously improve the alloy strength, but has little influence on the elastic modulus and plasticity.

For a further understanding of the invention, reference will now be made to the embodiments illustrated in the drawings, but it is to be understood that the description is intended to illustrate and describe further features and advantages of the invention, rather than to limit the scope of the appended claims.