阅读说明：本技术 一种低弹性模量高强度的医用锆基复合材料及其制备方法 (Medical zirconium-based composite material with low elastic modulus and high strength and preparation method thereof ) 是由 湛永钟 罗礼营 汤宏群 卢海滨 张嘉凯 舒适 于 2020-06-02 设计创作，主要内容包括：本发明公开一种低弹性模量高强度的医用锆基复合材料及其制备方法,属于医用生物材料领域,所述复合材料包括如下百分比原料：二硼化钛1.0～3.0wt.％,钛6.67～7.86wt.％,铌20.36～21.10wt.％,锆为余量。本发明是通过利用TiB<Sub>2</Sub>在含钛的锆基合金中的原位自生反应机理,将产生的TiB作为增强相来强化合金的性能,得到TiB增强相体积分数为2.54～7.70vol.％的锆基生物医用合金,经过物相分析、显微组织观察分析、力学性能及腐蚀性能等测试,其兼具有低弹性模量、高强度和综合性能较好的特性,符合临床医学对植入材料的要求。(The invention discloses a medical zirconium-based composite material with low elastic modulus and high strength and a preparation method thereof, belonging to the field of medical biomaterials, wherein the composite material comprises the following raw materials in percentage: titanium diboride 1.0-3.0 wt.%, titanium 6.67 &7.86 wt.%, niobium 20.36-21.10 wt.%, and zirconium for the balance. The invention is realized by utilizing TiB 2 In-situ self-generation reaction mechanism in the titanium-containing zirconium-based alloy, the generated TiB is used as a reinforcing phase to reinforce the performance of the alloy, so that the zirconium-based biomedical alloy with the volume fraction of the TiB reinforcing phase of 2.54-7.70 vol.% is obtained, and the alloy has the characteristics of low elastic modulus, high strength and good comprehensive performance after phase analysis, microscopic structure observation and analysis, mechanical property, corrosion performance and other tests, and meets the requirements of clinical medicine on implanted materials.)

1. The medical zirconium-based composite material with low elastic modulus and high strength is characterized by comprising the following raw materials in percentage by weight: 1.0-3.0 wt.% of titanium diboride, 6.67-7.86 wt.% of titanium, 20.36-21.10 wt.% of niobium and the balance of zirconium.

2. The low elastic modulus high strength medical zirconium based composite material according to claim 1, wherein the composite material comprises the following raw materials in percentage by weight: titanium diboride 1.0 wt.%, titanium 6.67 wt.%, niobium 21.10 wt.%, and the balance zirconium.

3. The medical zirconium based composite material with low elastic modulus and high strength according to claim 1, wherein the medical zirconium based composite material has 2.54 to 7.70 vol.% of TiB reinforcing phase.

4. The medical zirconium-based composite material with low elastic modulus and high strength as claimed in any one of claims 1 to 3, wherein the medical zirconium-based composite material has an elastic modulus of 29.93 to 32.81GPa and an elastic energy of 18.04 to 24.50MJ/m³The compressive strength is 1204-1397 MPa, and the extensibility is 33.01-39.04%.

5. A method for preparing a low modulus of elasticity high strength medical zirconium based composite material according to any of claims 1 to 4, comprising the steps of:

(1) weighing raw materials: respectively removing oxide skins on the surfaces of titanium diboride, titanium, niobium and zirconium, and weighing the raw materials according to the mass percentage of each component for later use;

(2) preparation before smelting: removing impurities in the vacuum furnace, stacking the weighed raw materials of titanium, zirconium, niobium and titanium diboride into the vacuum furnace in sequence according to the sequence of melting points from low to high, vacuumizing, and introducing argon;

(3) smelting a sample: and arc striking and smelting in an argon atmosphere, wherein the smelting temperature range is 3000-3500 ℃, and the zirconium-based composite material is obtained after the crucible copper and the sample are cooled to room temperature.

6. The method for preparing a low elastic modulus high strength medical zirconium based composite material according to claim 5, wherein in the step (2), the degree of vacuum in the vacuum furnace is 3.5 × 10^-3～6.5×10^-3Pa。

7. The method for preparing the medical zirconium-based composite material with low elastic modulus and high strength as claimed in claim 5, wherein in the step (3), the number of arc melting is 4-6.

8. The method for preparing the medical zirconium-based composite material with low elastic modulus and high strength as claimed in claim 5, wherein in the step (3), the melting voltage is 220V, and the melting current is controlled to be 100-200A.

Technical Field

The invention belongs to the field of biomedical materials, and particularly relates to a medical zirconium-based composite material with low elastic modulus and high strength and a preparation method thereof.

Background

Numerous studies have shown that if the material of the implant has a modulus of elasticity that is higher than that of the human bodyHigh, it will make the mechanical properties of the human hard tissue substitute material and natural bone not match, resulting in severe stress shielding effect. When external force acts on a human body, the stress borne by the implant material cannot be effectively transferred, so that bone absorption and loosening after the implant is implanted are caused, human bones are weakened and withered, the implant can be failed, and the human body can be injured.

Recently, stress shielding effect caused by mismatch of elastic deformation of the interface of the implant and the human tissue due to the difference of elastic modulus has attracted extensive attention of researchers and medical staff in the related field. The case of implant operation failure due to large difference of elastic modulus occurs frequently. At present, the elastic modulus of most metal medical biomaterials, such as titanium and alloy thereof, zirconium and alloy thereof is 55 GPa-125 GPa, which is far higher than that of natural bones of human bodies, and does not meet the applicable mechanical standard of human body implants. The elastic modulus of the traditional biomedical alloy Ti-6Al-4V reaches 110GPa, is much higher than that of human bones (10-30 GPa), contains V and Al elements, both have certain cytotoxicity, and if the alloy is enriched in a human body, a series of complications of the nervous system and the visceral system of the human body can be caused. Research shows that the enrichment of Al element easily causes Alzheimer disease (senile dementia), and the enrichment of V element easily causes kidney damage. The developed zirconium-based metal glass still has a much higher elastic modulus (80-119 GPa) than that of human bones, and has poor mechanical properties, thus not meeting the requirements of clinical medical application.

At present, the elastic modulus of single-phase beta titanium and zirconium alloys developed by a large number of researchers is extremely close to the natural skeleton of a human body and has good clinical applicability, so that the single-phase beta titanium and zirconium alloys become a novel biomedical material with a great application prospect. However, because of the metastable body-centered cubic structure of the single-phase beta-type titanium and zirconium alloy, the mechanical properties such as ultimate compressive strength, yield strength, hardness and the like are greatly reduced compared with the alpha-type titanium and zirconium alloy. In addition, the magnetic susceptibility of zirconium is much lower than that of titanium, so that image distortion caused by magnetization during nuclear magnetic resonance detection can be avoided, and the reliability of diagnosis is facilitated.

Therefore, there is a need for development of a novel medical biomaterial having both low elastic modulus and high strength and excellent overall performance.

Disclosure of Invention

In order to solve the technical problems, the invention provides a medical zirconium-based composite material with low elastic modulus and high strength and a preparation method thereof.

In order to achieve the purpose, the invention provides the following technical scheme:

a medical zirconium-based composite material with low elastic modulus and high strength is prepared from titanium diboride, titanium, niobium and zirconium, and is a zirconium-based biomedical alloy with 2.54-7.70 vol.% of TiB reinforcing phase.

Further, the composite material comprises the following raw materials in percentage by weight: 1.0-3.0 wt.% of titanium diboride, 6.67-7.86 wt.% of titanium, 20.36-21.10 wt.% of niobium and the balance of zirconium.

Further, the composite material comprises the following raw materials in percentage by weight: titanium diboride 1.0 wt.%, titanium 6.67 wt.%, niobium 21.10 wt.%, and the balance zirconium.

Furthermore, the elastic modulus of the composite material is 29.93-32.81 GPa, and the elastic energy is 18.04-24.50 MJ/m³The maximum compression strength is 1204-1397 MPa, and the extensibility is 33.01-39.04%.

The invention provides a preparation method of a medical zirconium-based composite material with low elastic modulus and high strength, which comprises the following steps:

(1) weighing raw materials: respectively removing oxide skins on the surfaces of titanium diboride, titanium, niobium and zirconium, and weighing the raw materials according to the mass percentage of each component for later use;

(2) preparation before smelting: removing impurities in the vacuum furnace, sequentially stacking the weighed raw materials of titanium, zirconium, niobium and titanium diboride into the vacuum furnace from low melting point to high melting point, vacuumizing, and introducing argon;

(3) smelting a sample: and arc striking and smelting in an argon atmosphere, wherein the smelting temperature range is 3000-3500 ℃, and the composite material is obtained after the crucible copper and the sample are cooled to room temperature.

Further, in the step (2), the steps of vacuumizing and introducing argon for washing are repeated for 2-3 times, and residual air in the furnace is removed as much as possible.

Further, in the step (2), the degree of vacuum in the vacuum furnace was 3.5 × 10^-3～6.5×10^-3Pa。

Further, in the step (3), the number of times of arc melting is 4-6.

Further, in the step (3), the smelting voltage is 220V, and the smelting current is controlled to be 100-200A.

The reaction principle of the invention is as follows: TiB₂Reacts with Ti in the material:

Ti+B→TiB (1)

Ti+2B→TiB₂(2)

TiB₂+Ti→2 TiB (3)

according to the thermodynamic theory of the reaction system, the reaction energy is carried out with the proviso that the Gibbs free energy change (. DELTA.G) < 0. After approximate processing is adopted, the delta G expression of the reaction formula is obtained as follows:

(1) formula (II): Δ G ═ 163176+5.86T

(2) Formula (II): Δ G ═ 142256+10.25T

(3) Formula (II): Δ G ═ 41840-8.79T

According to the thermodynamic criterion of the in-situ spontaneous reaction, the fact that the 3 reactions can be carried out within the temperature range of 500-3000K can be obtained. According to the thermodynamic theory, the larger the absolute value of Δ G < 0, the easier the reaction proceeds under the same conditions, and the arrangement of Δ G is from small to large: (1) < 2 > < 3 >, the available reaction (1) proceeds first in thermodynamic terms.

However, since △ G is also negative in reaction (3), Ti in the material causes the reaction to proceed toward the generation of TiB, and thus both thermodynamic calculations and chemical equilibrium analysis indicate that TiB is generated₂And finally forms a TiB strengthening phase with more stable thermodynamic property in the matrix with Ti. The TiB reinforcing phase is used as the in-situ reinforcing ceramic phase of the composite material and has good affinity.

The invention has the following beneficial effects:

1. the material is prepared from titanium diboride, titanium, niobium and zirconium, the zirconium-based composite material is generated by using a method for generating the reinforcing phase TiB by in-situ self-generation of the titanium diboride and the titanium, the reinforcing phase TiB is in-situ nucleated and grown from a metal aggregate, the thermodynamic property of the reinforcing phase is stable, the surface of the reinforcing body is free from pollution, a series of problems of surface (interface) wetting, interface reaction and the like of the reinforcing body and a base body in the conventional preparation process are avoided, and the processes of independent synthesis, addition, treatment and the like of the reinforcing body are omitted, so that the process difficulty and the cost are reduced; the reinforcement has good compatibility with the matrix, stable interface and high interface bonding strength.

2. The invention adopts an in-situ autogenous strengthening process to combine TiB fibers or particles as ceramic reinforcing phase with beta-type zirconium and niobium alloy phase to obtain the metal-based medical composite material with a single-phase beta-type alloy matrix, and optimizes the comprehensive mechanical property and corrosion resistance of the alloy while keeping the advantage of low elastic modulus of metastable beta phase. The reinforcing phase TiB has good chemical stability, excellent specific strength and rigidity, excellent impact conductivity and corrosion resistance, and does not contain cytotoxic elements; the composite material has 2.54-7.70 vol.% of TiB reinforcing phase obtained by calculation, the TiB reinforcing phase has good reactivity in the novel zirconium-based alloy, the reaction condition is simple and easy to achieve, the TiB reinforcing phase is well combined with a metal matrix, the inherent brittleness of the TiB reinforcing phase can be effectively eliminated, the fatigue damage of the TiB reinforcing phase under the physiological condition can be effectively eliminated, and the respective advantages of the two materials of transition metal and active ceramic can be exerted.

3. The biomedical composite material designed by the invention has the elastic modulus of 29.93-32.81 GPa and the elastic energy of 18.04-24.50 MJ/m³The maximum compression strength is 1204-1397 MPa, and the extensibility is 33.01-39.04%. Therefore, the processing property is good, and the requirements of clinical medicine on implantation materials are met. The excellent comprehensive performance also makes the material become a potential biomedical material with wide application prospect.

4. When the material is manufactured, the vacuum melting furnace with the copper crucible water cooling structure is used for melting, raw materials are sequentially placed in the vacuum melting furnace from low melting point to high melting point during melting, the placed raw materials are firstly contacted with electric arc, the temperature is high, the raw materials at the bottom are contacted with the water-cooled copper crucible, the temperature is low, and therefore alloy can be uniformly mixed and fully reacted while the melting loss rate is effectively reduced. The preparation method is simple and easy to operate, high in efficiency and low in cost.

Drawings

FIG. 1 is a stress-strain plot for various embodiments of the present invention. (in the figure: curve A-example 1, curve B-example 2, and curve C-example 3).

FIG. 2 is an XRD pattern for each example of the present invention (a for example 1, b for example 2, and c for example 3).

FIG. 3 is a SEM photograph of example 1 of the present invention.

FIG. 4 is a Tafel polarization plot of example 1 of the present invention.

FIG. 5 is a SEM photograph of example 2 of the present invention.

FIG. 6 is a Tafel polarization plot of example 2 of the present invention.

FIG. 7 is a SEM photograph of example 3 of the present invention.

FIG. 8 is a Tafel polarization plot of example 3 of the present invention.

Detailed Description

The present invention is described in detail below with reference to specific embodiments, which are provided for illustration only and are not intended to limit the invention.