Medical alloy material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of medical materials, and discloses a medical alloy material and a preparation method and application thereof. The medical alloy material comprises the following components in percentage by weight: 90 to 98 percent of Zn, 1.2 to 3.8 percent of Mg, 0.3 to 1.4 percent of Ti, 0.1 to 1.1 percent of V, 0.2 to 2.3 percent of Fe and 0.1 to 0.6 percent of Sc. Through specific element components and contents, the medical alloy material is refined in structure grain and compact in structure, and different elements form an alloy, so that the mechanical strength and the corrosion resistance of the medical alloy material are remarkably improved, and particularly, the tensile strength is remarkably improved. And the medical alloy material has good biocompatibility, so that the medical alloy material can be applied to the field of medical apparatuses and instruments.

Description

Technical Field

[0001] The invention belongs to the technical field of medical materials, and in particular relates to a medical alloy material and a preparation method and application thereof. Background Art

[0002] Magnesium alloys or zinc alloys have good biocompatibility, which makes them widely used in the field of medical devices, such as human bones or heart stents.

[0003] However, the existing magnesium alloys or zinc alloys have poor mechanical strength in the human body or have too fast corrosion rates, which will further lead to a decrease in the mechanical properties of the magnesium alloys or zinc alloys.

[0004] Therefore, there is an urgent need to provide a new medical alloy material with good mechanical strength and corrosion resistance. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention provides a medical alloy material and a preparation method and application thereof, wherein the medical alloy material has good mechanical strength and corrosion resistance. The medical alloy material is used to make medical devices, which has good application prospects in the human body.

[0006] A first aspect of the present invention provides a medical alloy material.

[0007] Specifically, a medical alloy material includes, by weight percentage, Zn 90-98%, Mg 1.2-3.8%, Ti 0.3-1.4%, V 0.1-1.1%, Fe 0.2-2.3%, and Sc 0.1-0.6%.

[0008] Preferably, the medical alloy material comprises, by weight percentage, Zn 91.8-97.3%, Mg 1.5-3.5%, Ti 0.5-1.2%, V 0.1-1%, Fe 0.5-2%, and Sc 0.1-0.5%.

[0009] Preferably, the medical alloy material further includes inevitable impurities, and the total content of the inevitable impurities does not exceed 0.5%, more preferably does not exceed 0.3%, and more preferably does not exceed 0.1%.

[0010] Preferably, the unavoidable impurities include at least one of S, Cu, Ni and Si.

[0011] Preferably, the medical alloy material further comprises at least one of Ca and Mn. The addition of Ca and / or Mn can not only refine the grains of the medical alloy material, solidify the inevitable impurities, and help improve the mechanical strength and corrosion resistance of the medical alloy material, but also interact with other non-impurity metal elements in the medical alloy material, thereby improving the mechanical strength of the medical alloy material.

[0012] Preferably, the total weight percentage of Ca and / or Mn in the medical alloy material is 0.05-0.3%, more preferably 0.05-0.15%.

[0013] Preferably, the medical alloy material comprises, by weight percentage, Zn 91.8-97.3%, Mg 1.5-3.5%, Ti 0.5-1.2%, V 0.1-1%, Fe 1-2%, Sc 0.1-0.5%, Ca and / or Mn 0.05-0.3%.

[0014] A second aspect of the present invention provides a method for preparing a medical alloy material.

[0015] Specifically, a method for preparing a medical alloy material comprises the following steps:

[0016] (1) weighing Zn, Mg, Ti, V, Fe, and Sc metal raw materials, mixing them, and heating them under a protective gas atmosphere to obtain a molten material;

[0017] (2) cooling the melt to obtain an ingot;

[0018] (3) heating and keeping the ingot in step (2) warm, and then cooling it to obtain an alloy billet;

[0019] (4) The alloy blank of step (3) is treated with liquid carbon dioxide, and then homogenized under a protective gas atmosphere, and then hot extruded and cooled to obtain the medical alloy material.

[0020] Preferably, in step (1), the metal includes a single metal or a metal alloy.

[0021] Preferably, in step (1), the protective gas atmosphere includes nitrogen or a rare gas, such as argon or helium.

[0022] Preferably, in step (1), during the mixing process, Ca and / or Mn metal raw materials are also added.

[0023] Preferably, in step (1), the smelting temperature is 740-780° C., and the smelting time is 5-15 minutes.

[0024] Preferably, in step (2), the cooling process is carried out in steps, first cooling to 400-500°C at a rate of 5-10°C / min and keeping warm for 20-40 minutes, then cooling to 100-180°C at a rate of 8-15°C / min and keeping warm for 30-60 minutes, and finally cooling to room temperature at a rate of 1-5°C / min. This step-by-step cooling process can fully remove the internal stress of the ingot, which is beneficial to improving the mechanical strength of the final medical alloy material, especially the tensile strength can be significantly improved.

[0025] Preferably, in step (3), the insulation temperature is 350-450° C., and the insulation time is 20-30 minutes.

[0026] Preferably, in step (3), the cooling process is to cool the temperature to 150-250°C at a rate of 1-8°C / min, and then cool the temperature to room temperature at a rate of 10-15°C / min. This cooling process is beneficial to improving the mechanical strength of the medical alloy material.

[0027] Preferably, in step (4), the liquid carbon dioxide treatment time is 30-80 minutes, more preferably 40-50 minutes.

[0028] Preferably, in step (4), the temperature of the homogenization treatment is 400-500° C., and the time is 40-80 minutes. More preferably, the temperature of the homogenization treatment is 460-480° C., and the time is 50-70 minutes.

[0029] Preferably, in step (4), the temperature of the hot extrusion molding process is 200-300°C.

[0030] Preferably, in step (4), the extrusion ratio of the hot extrusion molding process is 8-30, and more preferably 10-30.

[0031] Preferably, the extrusion rate is 0.2-2 mm / s, and further preferably, the extrusion rate is 0.5-1.5 mm / s.

[0032] Preferably, in step (4), the cooling is natural cooling to room temperature.

[0033] The preparation method of the medical alloy material of the present invention undergoes cooling in step (2), cooling in step (3), and liquid carbon dioxide treatment in step (4), and is combined with other heat treatment processes such as homogenization treatment and hot extrusion molding treatment. The specific high and low temperature alternating treatment process allows the medical alloy material to fully release internal stress in steps and has a promoting effect on grain refinement, thereby significantly improving the mechanical strength and corrosion resistance of the medical alloy material.

[0034] A third aspect of the present invention provides a use of a medical alloy material.

[0035] A medical device comprises the above-mentioned medical alloy material.

[0036] Preferably, the medical device includes a medical steel nail, a bone stent or a heart stent.

[0037] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0038] (1) The medical alloy material of the present invention comprises, by weight percentage, Zn90-98%, Mg1.2-3.8%, Ti0.3-1.4%, V0.1-1.1%, Fe0.2-2.3%, and Sc0.1-0.6%. Through the specific element components and contents, the medical alloy material has a refined grain structure and a dense structure, and alloys are formed between different elements, thereby significantly improving the mechanical strength and corrosion resistance of the medical alloy material, especially the tensile strength. The medical alloy material of the present invention has good biocompatibility, and therefore can be used in the field of medical devices.

[0039] (2) The preparation method of the present invention, through multiple cooling treatments combined with heat treatment processes (such as homogenization treatment and hot extrusion molding treatment), makes the prepared medical alloy material have good mechanical strength and corrosion resistance. DETAILED DESCRIPTION

[0040] In order to make the technical scheme of the present invention more clearly understood by those skilled in the art, the following embodiments are listed for illustration. It should be pointed out that the following embodiments do not limit the protection scope of the present invention.

[0041] Unless otherwise specified, the raw materials, reagents or devices used in the following examples can be obtained from conventional commercial sources or by existing known methods.

[0042] The purity of the metal raw materials used in the following examples and comparative examples is greater than or equal to 99.9%, and can be obtained through conventional commercial channels.

[0043] Example 1

[0044] A medical alloy material consists of the following components by weight: 2.5% Mg, 0.5% Ti, 0.3% V, 1.2% Fe, 0.5% Sc, and the balance Zn and inevitable impurities, wherein the total content of the inevitable impurities is less than 0.5%.

[0045] A method for preparing a medical alloy material comprises the following steps:

[0046] (1) weighing Zn, Mg, Ti, V, Fe, and Sc metal single substances and mixing them, heating them for smelting under a protective gas argon atmosphere, the smelting temperature being 760° C. and the smelting time being 10 minutes to obtain a melt;

[0047] (2) cooling the melt in steps, first cooling to 450° C. at a rate of 8° C. / min and keeping the temperature for 30 minutes, then cooling to 120° C. at a rate of 10° C. / min and keeping the temperature for 40 minutes, and finally cooling to room temperature at a rate of 3° C. / min to obtain an ingot;

[0048] (3) heating and keeping the ingot in step (2) at a temperature of 350° C. for 25 minutes, and then cooling the ingot at a rate of 5° C. / min to 150° C. and then at a rate of 10° C. / min to room temperature, to obtain an alloy billet;

[0049] (4) The alloy billet of step (3) is treated with liquid carbon dioxide for 40 minutes, and then homogenized under a protective gas argon atmosphere at a temperature of 450° C. for 50 minutes, and then hot extrusion is performed at a temperature of 240° C., an extrusion ratio of 12, an extrusion rate of 0.4 mm / s, and naturally cooled to room temperature to obtain a medical alloy material.

[0050] Example 2

[0051] A medical alloy material consists of the following components by weight: 1.8% Mg, 0.8% Ti, 0.5% V, 0.8% Fe, 0.2% Sc, and the balance Zn and inevitable impurities, wherein the total content of the inevitable impurities is less than 0.5%.

[0052] A method for preparing a medical alloy material comprises the following steps:

[0053] (1) weighing Zn, Mg, Ti, V, Fe, and Sc metal single substances and mixing them, heating them for smelting under a protective gas argon atmosphere, the smelting temperature being 750° C. and the smelting time being 12 minutes to obtain a melt;

[0054] (2) cooling the melt in steps, first cooling to 420° C. at a rate of 10° C. / min and keeping the temperature for 35 minutes, then cooling to 150° C. at a rate of 12° C. / min and keeping the temperature for 40 minutes, and finally cooling to room temperature at a rate of 2° C. / min to obtain an ingot;

[0055] (3) heating and keeping the ingot in step (2) at a temperature of 380° C. for 20 minutes, and then cooling the ingot at a rate of 2° C. / min to 180° C. and then at a rate of 10° C. / min to room temperature, to obtain an alloy billet;

[0056] (4) The alloy billet of step (3) is treated with liquid carbon dioxide for 45 minutes, and then homogenized under a protective gas argon atmosphere at a temperature of 450° C. for 50 minutes, and then hot extrusion is performed at a temperature of 240° C., an extrusion ratio of 12, and an extrusion rate of 0.4 mm / s. The billet is naturally cooled to room temperature to obtain a medical alloy material.

[0057] Example 3

[0058] A medical alloy material consists of the following components by weight: 2.5% Mg, 0.5% Ti, 0.3% V, 1.2% Fe, 0.5% Sc, 0.2% Ca, and the balance Zn and inevitable impurities, wherein the total content of the inevitable impurities is less than 0.5%.

[0059] A method for preparing a medical alloy material comprises the following steps:

[0060] (1) weighing Zn, Mg, Ti, V, Fe, Sc, and Ca metal single substances and mixing them, heating them for smelting under a protective gas argon atmosphere, the smelting temperature being 760° C. and the smelting time being 10 minutes to obtain a melt;

[0061] (2) cooling the melt in steps, first cooling to 450° C. at a rate of 8° C. / min and keeping the temperature for 30 minutes, then cooling to 120° C. at a rate of 10° C. / min and keeping the temperature for 40 minutes, and finally cooling to room temperature at a rate of 3° C. / min to obtain an ingot;

[0062] (3) heating and keeping the ingot in step (2) at a temperature of 350° C. for 25 minutes, and then cooling the ingot at a rate of 5° C. / min to 150° C. and then at a rate of 10° C. / min to room temperature, to obtain an alloy billet;

[0063] (4) The alloy billet of step (3) is treated with liquid carbon dioxide for 40 minutes, and then homogenized under a protective gas argon atmosphere at a temperature of 450° C. for 50 minutes, and then hot extrusion is performed at a temperature of 240° C., an extrusion ratio of 12, an extrusion rate of 0.4 mm / s, and naturally cooled to room temperature to obtain a medical alloy material.

[0064] Example 4

[0065] A medical alloy material consists of the following components by weight: 2.5% Mg, 0.5% Ti, 0.3% V, 1.2% Fe, 0.5% Sc, 0.1% Mn, and the balance Zn and inevitable impurities, wherein the total content of the inevitable impurities is less than 0.5%.

[0066] A method for preparing a medical alloy material comprises the following steps:

[0067] (1) weighing Zn, Mg, Ti, V, Fe, Sc, and Mn metal single substances and mixing them, heating them for smelting under a protective gas argon atmosphere, the smelting temperature being 760° C. and the smelting time being 10 minutes to obtain a melt;

[0068] (2) cooling the melt in steps, first cooling to 450° C. at a rate of 8° C. / min and keeping the temperature for 30 minutes, then cooling to 120° C. at a rate of 10° C. / min and keeping the temperature for 40 minutes, and finally cooling to room temperature at a rate of 3° C. / min to obtain an ingot;

[0069] (3) heating and keeping the ingot in step (2) at a temperature of 350° C. for 25 minutes, and then cooling the ingot at a rate of 5° C. / min to 150° C. and then at a rate of 10° C. / min to room temperature, to obtain an alloy billet;

[0070] (4) The alloy billet of step (3) is treated with liquid carbon dioxide for 40 minutes, and then homogenized under a protective gas argon atmosphere at a temperature of 450° C. for 50 minutes, and then hot extrusion is performed at a temperature of 240° C., an extrusion ratio of 12, an extrusion rate of 0.4 mm / s, and naturally cooled to room temperature to obtain a medical alloy material.

[0071] Comparative Example 1

[0072] Compared with Example 1, the difference of Comparative Example 1 is that an equal amount of Nb is used to replace V in Example 1, and other compositions and processes are the same as those of Example 1.

[0073] Comparative Example 2

[0074] Compared with Example 1, the difference of Comparative Example 2 is that the Ti in Example 1 is replaced by an equal amount of Sn, and the other compositions and processes are the same as those of Example 1.

[0075] Comparative Example 3

[0076] Compared with Example 1, the difference of Comparative Example 3 is that the Sc in Example 1 is replaced by an equal amount of Nb, and the other compositions and processes are the same as those of Example 1.

[0077] Comparative Example 4

[0078] Compared with Example 1, the difference of Comparative Example 4 is only that the composition of the medical alloy material is changed, and the other processes are the same as those of Example 1. The medical alloy material of Comparative Example 4 is composed of the following components by weight percentage: Mg 2.5%, Ti 0.5%, V 0.05%, Fe 0.1%, Sc 0.7%, and the balance Zn and inevitable impurities, and the total content of inevitable impurities is less than 0.5%.

[0079] Comparative Example 5

[0080] Compared with Example 1, the difference of Comparative Example 5 is that the cooling process of step (2) and step (3) is set to directly cool to room temperature at a rate of 10°C / min, and liquid carbon dioxide treatment is not performed in step (4).

[0081] Product effect testing

[0082] 1. Mechanical strength test

[0083] The medical alloy materials prepared in the above embodiments and comparative examples were taken, and the tensile strength and yield strength of the medical alloy materials were tested with reference to GB / T228.1-2021 "Tensile Test of Metallic Materials Part 1: Room Temperature Test Method". The results are shown in Table 1.

[0084] Table 1

[0085] Tensile strength(MPa) Yield strength(MPa) Example 1 389 290 Example 2 382 278 Example 3 395 292 Example 4 393 291 Comparative Example 1 362 253 Comparative Example 2 375 266 Comparative Example 3 340 235 Comparative Example 4 379 268 Comparative Example 5 359 247

[0086] It can be seen from Table 1 that the tensile strength and yield strength of the medical alloy material prepared in the example are significantly better than those in the comparative example.

[0087] It can be seen from Example 1 and Comparative Examples 1-4 that the element composition and content of the medical alloy material of the present invention have a significant effect on the tensile strength and yield strength of the material, which also shows that the medical alloy material of the present invention is selective with respect to the element type and content.

[0088] 2. Corrosion resistance test

[0089] The medical alloy materials prepared in Example 1, Example 3, and Comparative Example 1 and Comparative Example 5 were tested for corrosion resistance according to the following method.

[0090] Take the medical alloy material, weigh it as W1, and the length, width and height of the medical alloy material. The length, width and height can be used to calculate the surface area, and then place it in a beaker. According to the ratio of the surface area of ​​the medical alloy material to the volume of Hank's balanced salt solution, it is 20cm 2:1mL of Hank's balanced salt solution was added to soak the medical alloy material, and then soaked in a water bath at a constant temperature of 37°C for 30 days. After soaking, the medical alloy material was ultrasonically cleaned with a 200g / L chromic acid solution for 5 minutes to remove the corrosion formed on the surface of the medical alloy material, dried, and then the weight of the medical alloy material was measured as W2, and the weight loss of the medical alloy material was obtained as W1-W2. The total weight loss W of the medical alloy material was calculated using the weight loss, surface area, and soaking time (days or d) (the unit of W is mg·cm -2 ·d -1 ), and then calculate the average corrosion rate Pw of medical alloy materials according to ASTMG31-72, Pw = (8.76*10 4 *W) / (A*t*ρ)Table 2

[0091]

[0092] It can be seen from Table 2 that the corrosion resistance of the medical alloy material prepared in the example is significantly better than that in the comparative example.

[0093] It can be seen from the results of Example 1 and Comparative Examples 1 and 5 that Nb cannot be used to replace V in the medical alloy material, and the preparation method of the medical alloy material has a significant effect on the corrosion resistance of the prepared medical alloy material.

Claims

1. A medical alloy material, characterized in that: Calculated by weight percentage, it includes Zn 90-98%, Mg 1.2-3.8%, Ti 0.3-1.4%, V 0.1-1.1%, Fe 0.2-2.3%, and Sc 0.1-0.6%.

2. The medical alloy material according to claim 1, characterized in that: The medical alloy material comprises, by weight percentage, 91.8-97.3% Zn, 1.5-3.5% Mg, 0.5-1.2% Ti, 0.1-1% V, 0.5-2% Fe and 0.1-0.5% Sc.

3. The medical alloy material according to claim 1, characterized in that: The medical alloy material further includes inevitable impurities, and the total content of the inevitable impurities does not exceed 0.5%.

4. The medical alloy material according to claim 1, characterized in that: The medical alloy material further comprises at least one of Ca and Mn.

5. The medical alloy material according to claim 4, characterized in that: Calculated by weight percentage, it includes Zn 91.8-97.3%, Mg 1.5-3.5%, Ti 0.5-1.2%, V 0.1-1%, Fe 1-2%, Sc 0.1-0.5%, Ca and / or Mn 0.05-0.3%.

6. The method for preparing the medical alloy material according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) weighing Zn, Mg, Ti, V, Fe, and Sc metal raw materials, mixing them, and heating them in a protective gas atmosphere to obtain a molten material; (2) cooling the melt to obtain an ingot; (3) heating and keeping the ingot in step (2) warm, and then cooling to obtain an alloy billet; (4) The alloy blank of step (3) is treated with liquid carbon dioxide, and then homogenized under a protective gas atmosphere, and then hot extruded and cooled to obtain the medical alloy material.

7. The preparation method according to claim 6, characterized in that: In step (1), the metal includes a metal element or a metal alloy; and / or the protective gas atmosphere includes nitrogen or a rare gas; and / or, during the mixing process, Ca and / or Mn metal raw materials are also added; and / or, the smelting temperature is 740-780° C., and the smelting time is 5-15 minutes.

8. The preparation method according to claim 6, characterized in that: In step (2), the cooling process is carried out in steps, first cooling to 400-500°C at a rate of 5-10°C / min and keeping warm for 20-40 minutes, then cooling to 100-180°C at a rate of 8-15°C / min and keeping warm for 30-60 minutes, and finally cooling to room temperature at a rate of 1-5°C / min.

9. The preparation method according to claim 6, characterized in that: In step (3), the insulation temperature is 350-450°C, and the insulation time is 20-30 minutes; and / or, in step (3), the cooling process is to cool to 150-250°C at a rate of 1-8°C / minute, and then cool to room temperature at a rate of 10-15°C / minute; and / or, in step (4), the liquid carbon dioxide treatment time is 30-80 minutes; and / or, in step (4), the homogenization temperature is 400-500°C, and the time is 40-80 minutes; and / or, in step (4), the hot extrusion molding temperature is 200-300°C; and / or, in step (4), the extrusion ratio of the hot extrusion molding treatment is 8-30; and / or, the extrusion rate is 0.2-2mm / s; and / or, in step (4), the cooling is natural cooling to room temperature.

10. A medical device, characterized in that: The medical alloy material comprises the medical alloy material according to any one of claims 1 to 5.

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