CN108165782B - A kind of medical zinc-based alloy strip and preparation method thereof - Google Patents

Abstract

The invention discloses a medical zinc-based alloy strip and a preparation method thereof. The alloy strip is composed of the following substances: Mg 0.2-3wt.%, Li 0.05-1.5wt.%, Ca 0.02-0.5wt.%, Y 0.02～0.3wt.%, the rest are Zn and a small amount (content<0.1wt.%) of inevitable impurities. The alloy ingot obtained by smelting undergoes a series of combination of plastic deformation processing and annealing process to prepare ultra-thin alloy strip, and at the same time realize the regulation and refinement of alloy structure, and achieve the effect of significantly improving its comprehensive mechanical properties. The medical zinc-based alloy strip of the present invention has high strength and toughness (tensile strength of 283-451MPa, elongation at break: 19-42%), good biocompatibility, and suitably regulated degradation rate (0.07-0.23mm/year), etc. Many advantages belong to the field of preparation of medical zinc-based alloy implanted device materials, and it is expected to expand the scope of application of zinc-based alloys in more medical indications and medical devices.

Description

A kind of medical zinc-based alloy strip and preparation method thereof

technical field

The invention relates to a medical zinc-based alloy strip and a preparation technology thereof, and belongs to the technical field of preparation of medical zinc-based alloy implanted device materials.

Background technique

At present, inert non-degradable metal materials are mainly used for clinical implantation of medical metal materials, for example, (1) austenitic stainless steel 316LSS; (2) pure metals (titanium, niobium, zirconium, etc.); (3) titanium-based alloys; (4) ) cobalt-based alloy; (5) cobalt-chromium alloy; (6) nickel-chromium alloy; (7) nickel-titanium shape memory alloy. These biologically inert materials, which are usually retained in human tissues as permanent fixtures in the body, can remain stable for a long time, but they also have various drawbacks. For example, (1) after the permanent metal medical device is implanted into the human body, there is a tendency to form thrombus, resulting in in-stent restenosis and insufficient intimal fibrosis, and the implant cannot be removed. Once the blood vessel is blocked again at the same location, replantation (2) After the stainless steel, titanium alloy bone nails, bone plates, etc. are implanted into the human body, if they are removed through a second operation after the tissue is healed, it will increase the pain and economic burden of the patient, and at the same time This results in a waste of medical resources; (3) its higher elastic modulus will cause stress shielding effect, poor biocompatibility, and will diffuse harmful ions to surrounding tissues in a physiologically corrosive environment, causing toxic side effects to the human body and causing inflammation. Therefore, the development of medical materials with excellent mechanical properties and biocompatibility has become an important development direction in this field.

At present, in the field of degradable medical metal materials, iron-based alloys and magnesium-based alloys are the most intensively studied materials in recent years. However, the obvious defects of such degradable metal materials limit their wide application in this field. The corrosion rate of iron-based alloys is too slow, taking years to fully degrade, causing adverse human reactions similar to biologically inert materials. Although magnesium-based alloys have good biocompatibility, they have poor corrosion resistance and are quickly degraded in the human body, producing a large amount of hydrogen, which seriously affects the structural strength and mechanical support of implants.

In recent years, with the in-depth study of zinc and its alloys by scientific researchers, it has been found that zinc and its zinc alloys have great potential to become a new type of degradable medical metal materials. As one of the essential trace elements in the human body, zinc participates in almost all physiological metabolic processes in the human body. In addition to its catalytic and structural roles in a variety of metalloenzymes, transcription factors, and proteins, zinc also functions in neurotransmitter or modulator-like forms. It plays a role in promoting the metabolic renewal of cells and can enhance the body's immunity; it maintains the growth and development of the body, and zinc deficiency may lead to the disorder of all physiological functions of the body. The content of zinc in adults is 1.4-2.3g, and the dietary allowance of zinc for healthy adults is 15-40mg per day. Adults may only consume about 300mg of zinc per day to produce toxic reactions. Therefore, zinc alloys have good biocompatibility. At the same time, the standard electrode potential of pure zinc is -0.763V, which is between pure magnesium (-2.37V) and pure iron (-0.44V), and the corrosion rate of zinc-based alloys is between magnesium-based alloys and iron-based alloys. , so its degradation rate has certain advantages in matching the requirements of clinical plants.

However, the comprehensive mechanical properties of as-cast pure zinc are too poor, and the corrosion rate is also slow, making it difficult to meet the needs of clinical plants. Therefore, it is urgent to develop a new degradable zinc-based alloy with excellent comprehensive mechanical properties and controllable corrosion rate and its preparation method.

SUMMARY OF THE INVENTION

Technical problem: The present invention provides a medical zinc-based alloy strip that solves the problem of poor comprehensive mechanical properties of as-cast pure zinc, realizes controllable degradation rate of implant materials, improves the biocompatibility of materials, and realizes miniaturization of material size. materials and methods for their preparation.

Technical scheme: the medical zinc-based alloy strip of the present invention is prepared according to the following steps:

( ₁ ) Heat the metal zinc to _420-450 °C and keep warm. After the metal zinc is completely melted, when the melt temperature rises to 620-660°C, add metal lithium, metal calcium, Metal magnesium and metal yttrium, stir evenly, after all the metals are melted, stand to form an alloy melt, cool down to 520-560 ° C, and cast after standing to obtain an alloy ingot;

(2) keeping the alloy ingot at 310-350°C for 12-24 hours, and then air-cooling the alloy ingot to room temperature to obtain an alloy ingot blank;

(3) heat-extruding the alloy ingot blank at 150-250° C. for 15-30 min, and the extrusion ratio is (9-36): 1 to obtain alloy thick wire;

(4) subjecting the obtained alloy thick wire to multi-pass cold drawing at room temperature to finally obtain an alloy wire with φ=0.1-0.3 mm;

(5) rolling the alloy wire obtained by multi-pass cold drawing on a finishing mill, and processing it into a medical zinc-based alloy strip with a width of 4-15 mm and a thickness of 10-60 μm.

Further, in the medical zinc-based alloy strip of the present invention, the parts by mass of the raw materials in the step (1) are: 0.2-3 parts of Mg, 0.05-1.5 parts of Li, 0.02-0.5 parts of Ca, and 0.02-0.1 parts of Y parts, Zn94.7 ~ 99.71 parts.

Further, in the medical zinc-based alloy strip of the present invention, in the step (1), it also includes injecting hexachloroethane into the alloy melt for refining, and the injection amount of the hexachloroethane accounts for the total mass of the alloy melt. 0.2 to 0.5% of the alloy, then cooled to 520 to 560° C., and cast for 10 to 30 minutes to obtain an alloy ingot.

Further, in the medical zinc-based alloy strip of the present invention, in the cold drawing process of the step (4), the deformation amount of the wire material per pass is 9-20%, and when the cumulative deformation amount reaches 180-200% An annealing is performed once, and the annealing temperature is 200-300° C. and the time is 10-20 min.

Further, in the medical zinc-based alloy strip of the present invention, in the step (5), the alloy thin strip obtained by rolling is also subjected to a final pass annealing treatment, the temperature is 200-300 ° C, and the time is 10-20 min, Then air-cool to room temperature.

In the medical zinc-based alloy strip of the present invention, the mass percentage of impurities is less than or equal to 0.1, and the impurities may be Fe, Mn, Cu, Si and the like.

The medical zinc-based alloy strip of the invention has a tensile strength of 283-451 MPa and a fracture elongation of 19-42%.

For the medical zinc-based alloy strip of the present invention, the corrosion rate in the simulated body fluid is 0.07-0.23 mm/year.

The cytotoxicity of the medical zinc-based alloy strip of the invention is 0-1, and has good biocompatibility.

The preparation method of the medical zinc-based alloy strip of the present invention comprises the following steps:

( ₁ ) Heat the metal zinc to _420-450 °C and keep warm. After the metal zinc is completely melted, when the melt temperature rises to 620-660°C, add metal lithium, metal calcium, Metal magnesium and metal yttrium, stir evenly, after all the metals are melted, stand to form an alloy melt, cool down to 520-560 ° C, and cast after standing to obtain an alloy ingot;

(2) keeping the alloy ingot at 310-350°C for 12-24 hours, and then air-cooling the alloy ingot to room temperature to obtain an alloy ingot blank;

(3) heat-extruding the alloy ingot blank at 150-250° C. for 15-30 min, and the extrusion ratio is (9-36): 1 to obtain alloy thick wire;

(4) subjecting the obtained alloy thick wire to multi-pass cold drawing at room temperature to finally obtain an alloy wire with φ=0.1-0.3 mm;

(5) rolling the alloy wire obtained by multi-pass cold drawing on a finishing mill, and processing it into a medical zinc-based alloy strip with a width of 4-15 mm and a thickness of 10-60 μm.

Further, in the method of the present invention, the parts by mass of the raw materials in the step (1) are: 0.2-3 parts of Mg, 0.05-1.5 parts of Li, 0.02-0.5 parts of Ca, 0.02-0.1 parts of Y, 94.7 parts of Zn ~ 99.71 servings.

Further, in the method of the present invention, in the step (1), hexachloroethane is also injected into the alloy melt for refining, and the injection amount of the hexachloroethane accounts for 0.2-0.5% of the total mass of the alloy melt, Then, the temperature is lowered to 520-560° C., and the alloy ingot is obtained by casting after standing for 10-30 minutes.

Further, in the method of the present invention, in the cold drawing process of the step (4), the deformation amount of each pass of the wire is 9-20%, and when the cumulative deformation amount reaches 180-200%, annealing is performed once, The temperature is 200～300℃, and the time is 10～20min.

Further, in the method of the present invention, in the step (5), the alloy thin strip obtained after rolling is also subjected to final pass annealing treatment, the temperature is 200-300 ° C, the time is 10-20 min, and then air-cooled to room temperature.

In step 1 of the present invention, in order to obtain a medical zinc-based alloy strip with high strength and toughness, controllable degradation rate matching, and good biocompatibility, it is necessary to strictly control the content of impurities such as Fe, Mn, Cu, Si (<0.1wt .%). The strip obtained after step (5) has a width of 4-15 mm and a thickness of 10-60 μm.

In the preparation of degradable medical instruments, the above-mentioned medical zinc-based alloy strips of the present invention may include intraosseous implants, implanted instruments for maxillofacial surgery and craniocerebral surgery, various surgical patches and other medical implanted instruments and various medical instruments , such as shells of active implantable electronic medical equipment, surgical instruments, etc.

The medical zinc-based alloy strip of the present invention and the preparation method thereof have high strength, toughness and good biocompatibility, and can also adjust the corrosion degradation rate in the living body.

Beneficial effect: Compared with the prior art, the present invention has the following advantages:

1. Compared with traditional inert metal materials, a medical zinc-based alloy strip of the present invention can be used as a medical implant to degrade naturally in the body, and after the medical effect is achieved, it will be degraded from the body within a certain period of time, and it can be safely metabolized. Excretion from the body reduces the economic burden of the patient and also allows the patient to avoid the pain caused by the second surgery to remove the implant.

2. Alloy elements such as magnesium, calcium, lithium and other elements in a medical zinc-based alloy strip of the present invention can effectively refine the grains, significantly improve the strength and plasticity of the alloy, and at the same time maintain the corrosion resistance of the alloy. consistency. The tensile strength of as-cast pure zinc is only 20MPa, and the mechanical properties of the material can be greatly improved by the addition and adjustment of alloying elements.

3. Due to the close-packed hexagonal structure of zinc alloy, the slip system has poor plastic deformation ability. Through the combination of plastic deformation and intermediate annealing process, the medical zinc-based alloy of the present invention can effectively soften the work hardening phenomenon caused by plastic deformation, and realize the feasibility of large plastic deformation and small-sized ultra-thin zinc-based alloy strip preparation. , thus providing more possibilities for its application in medical implantation.

4. For the medical zinc-based alloy strip of the present invention, the addition amount of alloying elements can be adjusted according to the performance requirements of different medical implants, so as to obtain corresponding mechanical properties and corrosion resistance. If the content of magnesium, calcium, etc. is appropriately reduced, corrosion-resistant materials with medium strength and high plasticity can be obtained, which are suitable for drawing into wire rods, pipes for brackets, or rolling into strips and plates; appropriately increase magnesium elements , calcium, etc., high-strength and medium-plastic materials can be obtained, which are suitable for intraosseous implantation.

5. Compared with magnesium-based alloys and iron-based alloys, the medical zinc-based alloy strip of the present invention has a relatively suitable corrosion rate in simulated body fluids, which is 0.07-0.23 mm/year, and can maintain structural support during its service period. It maintains the physical and mechanical integrity, and is metabolically discharged after tissue healing, meeting the corrosion rate requirements of implant materials.

6. Although the safety of zinc alloy for medical implantation is still in the exploratory stage, a medical zinc-based alloy strip of the present invention has good biocompatibility, and the cytotoxicity is 0-1, which is in line with medical implantation. Enter the material standard. Similar to the zinc element, the magnesium element in the alloy of the present invention is also one of the essential elements of the human body; the magnesium has good biocompatibility and biosafety. Magnesium is an indispensable mineral element in the process of human metabolism. Generally, adults need to consume 300-350mg of magnesium per day. In the experiment of magnesium metal implantation in animals, it was found that magnesium ions can enhance the activity of osteoblasts and promote implantation. The growth of new bone around the object will not cause damage to the heart, liver, spleen, kidney and other important organs. Similar to zinc and magnesium elements, calcium and lithium are both elements contained in the human body. Calcium is beneficial to human bone health. Lithium can effectively improve and stabilize people's emotions. At the same time, trace amounts of yttrium are harmless to the human body.

Detailed ways

The present invention will be further described below in conjunction with the examples.

In the following examples, the purity of metal zinc ≥ 99.99%, the purity of metal magnesium ≥ 99.99%, the purity of metal lithium ≥ 99.99%, the purity of metal calcium ≥ 99.99%, the purity of metal yttrium ≥ 99.99%, in order to obtain both good For materials with comprehensive mechanical properties, biological corrosion properties and biocompatibility properties, the content of impurities Fe, Mn, Cu and Si should be strictly controlled.

The simulated body fluids when measuring the corrosion rate in the following examples, the components and their concentrations are: 8g/ _1NaCl , 0.4g/ _1KCl , 0.14g/ _1CaCl2 , 0.35g/ _1NaHCO3 , 1g/l _C6H12O6 , 0.1 g/1 MgCl ₂ ·6H ₂ O, 0.06 g/1 MgSO ₄ ·7H ₂ O, 0.06 g/1 KH ₂ PO ₄ , 0.06 g/1 Na ₂ HPO ₄ ·12H ₂ O.

Example 1:

For the medical zinc-based alloy strip of the present invention, the mass fractions of the raw materials used are as follows: 0.2 part of Mg, 0.05 part of Li, 0.02 part of Ca, 0.02 part of Y, 99.71 part of Zn, and the rest are Zn.

The preparation steps of the zinc-based alloy strip are as follows:

step 1,

(1) Weigh the raw materials according to the above-mentioned alloy ratio;

(2) After preheating the iron crucible coated with a protective layer on the inner wall, put metal zinc in it, heat it up to 420 °C and after the pure zinc is completely melted, when the zinc melt is heated to 620 °C, in a mixed atmosphere of CO ₂ and SF ₆ Add metal magnesium, metal calcium, metal lithium and metal yttrium under the protection, stir evenly, after all the metals are melted, let stand for a period of time to form an alloy melt, and cool down to 520 ℃;

(3) To the alloy melt, add hexachloroethane accounting for 0.2% of the total weight of the alloy melt in a mass ratio, stir and let stand for 10 minutes, and cast to obtain an alloy ingot.

Step 2, homogenization treatment:

(1) Keep the alloy ingot at 310°C for 12h;

(2) Air-cooling the heat-preserved alloy ingot to room temperature to obtain an alloy ingot blank.

Step 3, heat-extruding the alloy ingot blank at 150° C. for 15 minutes, with an extrusion ratio of 36:1, to obtain alloy thick wire;

In step 4, the obtained alloy thick wire is subjected to multi-pass cold drawing at room temperature, and finally an alloy filament with φ=0.1 mm is obtained; wherein, the deformation amount of each pass is 20%, and when the cumulative deformation amount reaches 200% annealing at 200°C for 10 minutes;

Step 5, Rolling:

(1) The alloy filaments obtained by multi-pass cold drawing are rolled on a finishing mill, and processed into ultra-thin alloy strips with a width of 15 mm and a thickness of 10 μm;

(2) The alloy thin strip obtained by rolling is subjected to final annealing treatment at a temperature of 200° C. for 10 minutes, and then air-cooled to room temperature to obtain an ultra-thin strip implanted in a high-strength and tough medical zinc-based alloy.

Example 2:

For the medical zinc-based alloy strip of the present invention, the mass fractions of the raw materials used are as follows: 0.3 part of Mg, 0.1 part of Li, 0.1 part of Ca, 0.05 part of Y, and 99.45 part of Zn.

The preparation steps of the zinc-based alloy strip are as follows:

step 1,

(1) Weigh the raw materials according to the above-mentioned alloy ratio;

(2) After preheating the iron crucible coated with a protective layer on the inner wall, put metal zinc in it, heat it up to 420 °C and after the pure zinc is completely melted, when the zinc melt is heated to 620 °C, in a mixed atmosphere of CO ₂ and SF ₆ Add metal magnesium, metal calcium, metal lithium and metal yttrium under the protection, stir evenly, after the metal is completely melted, let it stand for a period of time to form an alloy melt, and after cooling to 520 ℃, cast the alloy ingot.

Step 2, homogenization treatment:

(1) Keep the alloy ingot at 310°C for 24h;

(2) Air-cooling the heat-preserved alloy ingot to room temperature to obtain an alloy ingot blank.

Step 3, heat-extruding the alloy ingot blank at 150° C. for 20 minutes, with an extrusion ratio of 24:1, to obtain alloy thick wire;

In step 4, the obtained alloy thick wire is subjected to multi-pass cold drawing at room temperature, and finally an alloy filament with φ=0.1 mm is obtained; wherein, the deformation amount of each pass is 20%, and when the cumulative deformation amount reaches 200% annealing at 250 °C for 10 min;

Step 5, Rolling:

(1) The alloy filaments obtained by multi-pass cold drawing are rolled on a finishing mill, and processed into ultra-thin alloy strips with a width of 15 mm and a thickness of 20 μm;

(2) The alloy thin strip obtained by rolling is subjected to final annealing treatment at a temperature of 250° C. for 10 minutes, and then air-cooled to room temperature to obtain an ultra-thin strip implanted in a high-strength and tough medical zinc-based alloy.

Example 3:

For the medical zinc-based alloy strip of the present invention, the mass fractions of the raw materials used are as follows: 3 parts of Mg, 1.5 parts of Li, 0.5 parts of Ca, 0.3 parts of Y, and 94.7 parts of Zn.

The preparation steps of the zinc-based alloy strip are as follows:

step 1,

(1) Weigh the raw materials according to the above-mentioned alloy ratio;

(2) After preheating the iron crucible coated with a protective layer on the inner wall, put metal zinc in it, heat it up to 450 °C until the pure zinc is completely melted, and heat the zinc melt to 660 °C, in a mixed atmosphere of CO ₂ and SF ₆ Add metal magnesium, metal calcium, metal lithium and metal yttrium under the protection, stir evenly, after all the metals are melted, let stand for a period of time to form an alloy melt, and cool down to 560 ℃;

(3) To the alloy melt, add hexachloroethane accounting for 0.5% of the total weight of the alloy melt according to the mass ratio, stir, stand at 560° C. for 30 minutes, and cast to obtain an alloy ingot.

Step 2, homogenization treatment:

(1) Keep the alloy ingot at 350°C for 24h;

(2) Air-cooling the heat-preserved alloy ingot to room temperature to obtain an alloy ingot blank.

Step 3, heat-extruding the alloy ingot blank at 250° C. for 30 minutes, with an extrusion ratio of 9:1, to obtain alloy thick wire;

In step 4, the obtained alloy thick wire is subjected to multi-pass cold drawing at room temperature, and finally an alloy filament with φ=0.3 mm is obtained; wherein, the deformation amount of each pass is 9%, and when the cumulative deformation amount reaches 180% annealing at 300°C for 20min;

Step 5, Rolling:

(1) Roll the alloy wire obtained by multi-pass cold drawing on a finishing mill, and process it into an ultra-thin alloy strip with a width of 4 mm and a thickness of 60 μm;

(2) The alloy thin strip obtained by rolling is subjected to final annealing treatment at a temperature of 300° C. for 20 minutes, and then air-cooled to room temperature to obtain an ultra-thin strip implanted in a high-strength and tough medical zinc-based alloy.

Example 4:

For the medical zinc-based alloy strip of the present invention, the parts by mass of the raw materials used are as follows: 1.5 parts of Mg, 0.8 parts of Li, 0.3 parts of Ca, 0.12 parts of Y, and 97.28 parts of Zn.

The preparation steps of the zinc-based alloy strip are as follows:

step 1,

(1) Weigh the raw materials according to the above-mentioned alloy ratio;

(2) After preheating the iron crucible coated with a protective layer on the inner wall, put metal zinc, heat up to 430 °C and wait for the pure zinc to be completely melted. When the zinc melt is heated to 640 °C, in a mixed atmosphere of CO ₂ and SF ₆ Add metal magnesium, metal calcium, metal lithium and metal yttrium under the protection, stir evenly, after all the metals are melted, let stand for a period of time to form an alloy melt, and cool down to 530 ℃;

(3) To the alloy melt, add hexachloroethane accounting for 0.4% of the total weight of the alloy melt according to the mass ratio, stir, stand at 530° C. for 20 minutes, and cast to obtain an alloy ingot.

Step 2, homogenization treatment:

(1) Keep the alloy ingot at 330°C for 18h;

(2) Air-cooling the heat-preserved alloy ingot to room temperature to obtain an alloy ingot blank.

Step 3, heat-extruding the alloy ingot blank at 225° C. for 20 minutes, with an extrusion ratio of 16:1, to obtain alloy thick wire;

In step 4, the obtained alloy thick wire is subjected to multi-pass cold drawing at room temperature, and finally an alloy filament with φ=0.2 mm is obtained; wherein, the deformation amount of each pass is 16%, and when the cumulative deformation amount reaches 176% annealing at 250°C for 20 minutes;

Step 5, Rolling:

(1) The alloy filaments obtained by multi-pass cold drawing are rolled on a finishing mill, and processed into ultra-thin alloy strips with a width of 9 mm and a thickness of 30 μm;

(2) The alloy thin strip obtained by rolling is subjected to final annealing treatment at a temperature of 250° C. for 20 minutes, and then air-cooled to room temperature to obtain an ultra-thin strip implanted in a high-strength and tough medical zinc-based alloy.

Example 5:

For the medical zinc-based alloy strip of the present invention, the mass fractions of the raw materials used are as follows: 0.8 part of Mg, 0.3 part of Li, 0.12 part of Ca, 0.08 part of Y, and 98.7 part of Zn.

The preparation steps of the zinc-based alloy strip are as follows:

step 1,

(1) Weigh the raw materials according to the above-mentioned alloy ratio;

(2) After preheating the iron crucible coated with a protective layer on the inner wall, put metal zinc into it, and heat it up to 430 °C until the pure zinc is completely melted. When the zinc melt is heated to 630 °C, in a mixed atmosphere of CO ₂ and SF ₆ Add metal magnesium, metal calcium, metal lithium and metal yttrium under the protection, stir evenly, after all the metals are melted, let stand for a period of time to form an alloy melt, and cool down to 535 ℃;

(3) To the alloy melt, add hexachloroethane accounting for 0.3% of the total weight of the alloy melt by mass ratio, stir, stand at 535° C. for 15 minutes, and cast to obtain an alloy ingot.

Step 2, homogenization treatment:

(1) Keep the alloy ingot at 320°C for 12h;

(2) Air-cooling the heat-preserved alloy ingot to room temperature to obtain an alloy ingot blank.

Step 3, heat-extruding the alloy ingot blank at 200° C. for 30 minutes, with an extrusion ratio of 25:1, to obtain alloy thick wire;

In step 4, the obtained alloy thick wire is subjected to multi-pass cold drawing at room temperature, and finally an alloy filament with φ=0.1 mm is obtained; wherein, the deformation amount of each pass is 12%, and when the cumulative deformation amount reaches 192% annealing is carried out once, the annealing temperature is 225 ℃, and the time is 14 minutes;

Step 5, Rolling:

(1) The alloy filaments obtained by multi-pass cold drawing are rolled on a finishing mill, and processed into ultra-thin alloy strips with a width of 6 mm and a thickness of 20 μm;

(2) The alloy thin strip obtained by rolling is subjected to final annealing treatment at a temperature of 225° C. for 14 minutes, and then air-cooled to room temperature to obtain a high-strength and tough medical zinc-based alloy implanted ultra-thin strip.

Example 6:

For the medical zinc-based alloy thin strip material of the present invention, the mass fractions of the raw materials used are as follows: Mg is 2.4 parts, Li is 1 part, Ca is 0.35 parts, Y is 0.2 parts, and Zn is 96.05 parts.

The preparation steps of the zinc-based alloy strip are as follows:

step 1,

(1) Weigh the raw materials according to the above-mentioned alloy ratio;

(2) After preheating the iron crucible coated with a protective layer on the inner wall, put metal zinc in it, heat it up to 445 °C and after the pure zinc is completely melted, when the zinc melt is heated to 650 °C, in a mixed atmosphere of CO ₂ and SF ₆ Add metal magnesium, metal calcium, metal lithium and metal yttrium under the protection, stir evenly, after all the metals are melted, stand for a period of time to form an alloy melt, cool down to 550 ℃ and cast to obtain an alloy ingot.

Step 2, homogenization treatment:

(1) Keep the alloy ingot at 340°C for 18h;

(2) Air-cooling the heat-preserved alloy ingot to room temperature to obtain an alloy ingot blank.

Step 3, heat-extruding the alloy ingot blank at 225° C. for 30 minutes, with an extrusion ratio of 9:1, to obtain alloy thick wire;

In step 4, the obtained alloy thick wire is subjected to multi-pass cold drawing at room temperature, and finally an alloy filament with φ=0.3 mm is obtained; wherein, the deformation amount of each pass is 10%, and when the cumulative deformation amount reaches 180% annealing at 275°C for 15min;

Step 5, Rolling:

(1) Roll the alloy wire obtained by multi-pass cold drawing on a finishing mill, and process it into an ultra-thin alloy strip with a width of 5 mm and a thickness of 50 μm;

(2) The alloy thin strip obtained by rolling is subjected to final annealing treatment at a temperature of 250° C. for 20 minutes, and then air-cooled to room temperature to obtain an ultra-thin strip implanted in a high-strength and tough medical zinc-based alloy.

Example 7:

For the medical zinc-based alloy thin strip material of the present invention, the parts by mass of the raw materials used are as follows: 0.5 part of Mg, 0.2 part of Li, 0.12 part of Ca, 0.05 part of Y, and 99.13 part of Zn.

The preparation steps of the zinc-based alloy strip are as follows:

step 1,

(1) Weigh the raw materials according to the above-mentioned alloy ratio;

(2) After preheating the iron crucible coated with a protective layer on the inner wall, put metal zinc in it, heat it up to 425 °C until the pure zinc is completely melted, and heat the zinc melt to 630 °C, in a mixed atmosphere of CO ₂ and SF ₆ . Add metal magnesium, metal calcium, metal lithium and metal yttrium under the protection, stir evenly, after all the metals are melted, let stand for a period of time to form an alloy melt, and cool down to 530 ℃;

(3) To the alloy melt, add hexachloroethane accounting for 0.35% of the total weight of the alloy melt according to the mass ratio, stir, stand at 530° C. for 20 minutes, and cast to obtain an alloy ingot.

Step 2, homogenization treatment:

(1) Keep the alloy ingot at 320°C for 24h;

(2) Air-cooling the heat-preserved alloy ingot to room temperature to obtain an alloy ingot blank.

Step 3, heat-extruding the alloy ingot blank at 250° C. for 15 minutes, the extrusion ratio is 20:1, to obtain alloy thick wire;

In step 4, the obtained alloy thick wire is subjected to multi-pass cold drawing at room temperature, and finally an alloy filament with φ=0.1 mm is obtained; wherein, the deformation amount of each pass is 11%, and when the cumulative deformation amount reaches 198% annealing at 250°C for 15min;

Step 5, Rolling:

(1) Roll the alloy wire obtained by multi-pass cold drawing on a finishing mill, and process it into an ultra-thin alloy strip with a width of 12 mm and a thickness of 15 μm;

(2) The alloy thin strip obtained by rolling is subjected to final annealing treatment at a temperature of 275° C. for 15 minutes, and then air-cooled to room temperature to obtain an ultra-thin strip implanted in a high-strength and tough medical zinc-based alloy.

Example 8:

For the medical zinc-based alloy thin strip material of the present invention, the parts by mass of the raw materials used are as follows: 0.4 part of Mg, 0.05 part of Li, 0.02 part of Ca, 0.02 part of Y, and 99.51 part of Zn.

The preparation steps of the zinc-based alloy strip are as follows:

step 1,

(1) Weigh the raw materials according to the above-mentioned alloy ratio;

(2) After preheating the iron crucible coated with a protective layer on the inner wall, put metal zinc in it, heat it up to 450 °C and after the pure zinc is completely melted, when the zinc melt is heated to 650 °C, in a mixed atmosphere of CO ₂ and SF ₆ Add metal magnesium, metal calcium, metal lithium and metal yttrium under the protection, stir evenly, after the metal is completely melted, let it stand for a period of time to form an alloy melt, cool down to 560 ℃ and cast to obtain an alloy ingot.

Step 2, homogenization treatment:

(1) Keep the alloy ingot at 340°C for 24h;

(2) Air-cooling the heat-preserved alloy ingot to room temperature to obtain an alloy ingot blank.

Step 3, heat-extruding the alloy ingot blank at 220° C. for 30 minutes, with an extrusion ratio of 24:1, to obtain alloy thick wire;

In step 4, the obtained alloy thick wire is subjected to multi-pass cold drawing at room temperature, and finally an alloy filament with φ=0.1 mm is obtained; wherein, the deformation amount of each pass is 20%, and when the cumulative deformation amount reaches 180% annealing at 250°C for 15min;

Step 5, Rolling:

(1) Roll the alloy wire obtained by multi-pass cold drawing on a finishing mill, and process it into an ultra-thin alloy strip with a width of 4 mm and a thickness of 30 μm;

(2) The alloy thin strip obtained by rolling is subjected to final annealing treatment at a temperature of 275° C. for 15 minutes, and then air-cooled to room temperature to obtain an ultra-thin strip implanted in a high-strength and tough medical zinc-based alloy.

Example 9:

For the medical zinc-based alloy thin strip material of the present invention, the mass fractions of the raw materials used are as follows: 1.5 part of Mg, 0.2 part of Li, 0.5 part of Ca, 0.1 part of Y, and 97.7 part of Zn.

The preparation steps of the zinc-based alloy strip are as follows:

step 1,

(1) Weigh the raw materials according to the above-mentioned alloy ratio;

(2) After preheating the iron crucible coated with a protective layer on the inner wall, put metal zinc in it, heat it up to 430 °C until the pure zinc is completely melted, and heat the zinc melt to 660 °C, in a mixed atmosphere of CO ₂ and SF ₆ . Add metal magnesium, metal calcium, metal lithium and metal yttrium under the protection, stir evenly, after all the metals are melted, stand for a period of time to form an alloy melt, cool down to 550 ℃ and cast to obtain an alloy ingot.

Step 2, homogenization treatment:

(1) Keep the alloy ingot at 320°C for 24h;

(2) Air-cooling the heat-preserved alloy ingot to room temperature to obtain an alloy ingot blank.

Step 3, heat-extruding the alloy ingot blank at 250° C. for 30 minutes, with an extrusion ratio of 16:1, to obtain alloy thick wire;

In step 4, the obtained alloy thick wire is subjected to multi-pass cold drawing at room temperature, and finally an alloy filament with φ=0.2 mm is obtained; wherein, the deformation amount of each pass is 16%, and when the cumulative deformation amount reaches 192% annealing at 250 °C for 10 min;

Step 5, Rolling:

(1) Roll the alloy wire obtained by multi-pass cold drawing on a finishing mill, and process it into an ultra-thin alloy strip with a width of 6 mm and a thickness of 20 μm;

(2) The alloy thin strip obtained by rolling is subjected to final annealing treatment at a temperature of 275° C. for 10 minutes, and then air-cooled to room temperature to obtain a high-strength and tough medical zinc-based alloy implanted ultra-thin strip.

Example 10:

The in vitro cytotoxicity test was carried out with the medical zinc-based alloy strips prepared in Examples 1-9.

In this example, according to GB/T16886.5-2003, the in vitro cell (L-929 fibroblast) toxicity test was carried out on the medical zinc-based alloy tape material, and the cytotoxicity showed that the cytotoxicity was grade 0-1, and the degradation products had no obvious influence on the cell activity. and inhibition, showing excellent cytocompatibility.

Using the zinc-based alloy strips prepared in Examples 1 to 9, an in vitro simulated body fluid immersion experiment was performed, and the corrosion rates of the zinc-based alloy strips of each component were measured as shown in Table 1:

Table 1

In this example, the in vitro degradation rate of the zinc alloy strip was studied according to the ASTM-G31-72 standard test method, and it was found that in the simulated body fluid environment at 37°C, the degradation rate of the zinc alloy strip was moderate, maintained below 0.4 mm/y, and The corrosion degradation rate of the alloy can be regulated by the addition of alloying elements.

Table 2 shows the results of tensile experiments on the medical zinc-based alloy strips prepared in Examples 1 to 9.

Table 2

In this example, according to the GB/T228.1-2010 test standard, the tensile mechanical properties of the medical zinc alloy strips Examples 1 to 9 are tested, and the results are shown in Table 2. Studies have shown that the tensile strength of medical zinc alloy strips is up to 451MPa, and the elongation at break is up to 42%.

Claims (8)

1. a medical zinc-based alloy strip is characterized in that, this strip is prepared according to the following steps: ( ₁ ) Heat the metal zinc to _420-450 °C and keep warm. After the metal zinc is completely melted, when the melt temperature rises to 620-660°C, add metal lithium, metal calcium, Metal magnesium and metal yttrium, stir evenly, and after all the metals are melted, stand to form an alloy melt, cool down to 520-560 ° C, and cast after standing to obtain an alloy ingot. The mass fraction of raw materials is: 0.2-3 parts of Mg , Li 0.05～1.5 parts, Ca 0.02～0.5 parts, Y 0.02～0.1 parts, Zn 94.7～99.71 parts; (2) keeping the alloy ingot at 310-350°C for 12-24 hours, and then air-cooling the alloy ingot to room temperature to obtain an alloy ingot blank; (3) heat-extruding the alloy ingot blank at 150-250° C. for 15-30 min, and the extrusion ratio is (9-36): 1 to obtain alloy thick wire; (4) subjecting the obtained alloy thick wire to multi-pass cold drawing at room temperature to finally obtain an alloy wire with φ=0.1-0.3 mm; (5) rolling the alloy wire obtained by multi-pass cold drawing on a finishing mill, and processing it into a medical zinc-based alloy strip with a width of 4-15 mm and a thickness of 10-60 μm. 2 . The medical zinc-based alloy strip according to claim 1 , wherein in the step (1), it also comprises injecting hexachloroethane into the alloy melt for refining, and the injection of the hexachloroethane The amount accounts for 0.2-0.5% of the total mass of the alloy melt, then the temperature is lowered to 520-560 DEG C, and the alloy ingot is obtained by casting after standing for 10-30 minutes. 3 . The medical zinc-based alloy strip according to claim 1 or 2 , wherein in the cold drawing process of the step (4), the deformation amount of each pass of the wire is 9-20%. 4 . , when the cumulative deformation reaches 180-200%, an annealing is performed, the annealing temperature is 200-300 °C, and the time is 10-20 min. 4. A kind of medical zinc-based alloy strip according to claim 1 or 2, characterized in that, in the step (5), the alloy thin strip obtained by rolling is also subjected to final pass annealing treatment, and the temperature is 200～300℃, the time is 10～20min, and then air-cooled to room temperature. 5. a preparation method of medical zinc-based alloy strip, is characterized in that, this method comprises the following steps: ( ₁ ) Heat the metal zinc to _420-450 °C and keep warm. After the metal zinc is completely melted, when the melt temperature rises to 620-660°C, add metal lithium, metal calcium, Metal magnesium and metal yttrium, stir evenly, and after all the metals are melted, stand to form an alloy melt, cool down to 520-560 ° C, and cast after standing to obtain an alloy ingot. The mass fraction of raw materials is: 0.2-3 parts of Mg , Li 0.05～1.5 parts, Ca 0.02～0.5 parts, Y 0.02～0.1 parts, Zn 94.7～99.71 parts; (2) keeping the alloy ingot at 310-350°C for 12-24 hours, and then air-cooling the alloy ingot to room temperature to obtain an alloy ingot blank; (3) heat-extruding the alloy ingot blank at 150-250° C. for 15-30 min, and the extrusion ratio is (9-36): 1 to obtain alloy thick wire; (4) subjecting the obtained alloy thick wire to multi-pass cold drawing at room temperature to finally obtain an alloy wire with φ=0.1-0.3 mm; (5) rolling the alloy wire obtained by multi-pass cold drawing on a finishing mill, and processing it into a medical zinc-based alloy strip with a width of 4-15 mm and a thickness of 10-60 μm. 6. The preparation method of a medical zinc-based alloy strip according to claim 5, wherein in the step (1), hexachloroethane is also injected into the alloy melt for refining, and the hexachloroethane is The injection amount of ethane accounts for 0.2-0.5% of the total mass of the alloy melt, then the temperature is lowered to 520-560 DEG C, and the alloy ingot is obtained by casting after standing for 10-30 minutes. 7. The preparation method of a medical zinc-based alloy strip according to claim 5 or 6, wherein in the cold drawing process of the step (4), the deformation amount of each pass of the wire is 9 ～20%, when the cumulative deformation reaches 180～200%, annealing is performed once, the annealing temperature is 200～300℃, and the time is 10～20min. 8. The preparation method of a medical zinc-based alloy strip according to claim 5 or 6, wherein in the step (5), the alloy thin strip obtained after rolling is also subjected to a final pass Annealing treatment, the temperature is 200 ~ 300 ℃, the time is 10 ~ 20min, and then air-cooled to room temperature.