阅读说明：本技术 锌基合金材料的可降解血管支架及其制备方法 (Degradable intravascular stent made of zinc-based alloy material and preparation method thereof ) 是由 李贻成 宁靠 宋坤 刘江 于 2020-07-31 设计创作，主要内容包括：本发明提供了一种锌基合金材料的可降解血管支架及其制备方法,所述锌基合金材料的可降解血管支架为锌铜镁合金材料或锌镁锂合金材料的可降解血管支架,其质量百分比为：铜含量为0-5％,镁含量为0.01％-0.1％,锂含量为0-0.5％,其余为锌含量。本发明解决了因长期体内植入器械而导致体内生物学炎性和生物力学不适配,在体内无法降解的技术问题。(The invention provides a zinc-based alloy degradable intravascular stent and a preparation method thereof, wherein the zinc-based alloy degradable intravascular stent is a zinc-copper-magnesium alloy material or a zinc-magnesium-lithium alloy material, and the zinc-copper-magnesium-lithium alloy material comprises the following components in percentage by mass: 0 to 5 percent of copper, 0.01 to 0.1 percent of magnesium, 0 to 0.5 percent of lithium and the balance of zinc. The invention solves the technical problems of biological inflammation and biomechanics incompatibility in vivo and incapability of degrading in vivo due to long-term implantation of instruments in vivo.)

1. The degradable intravascular stent made of the zinc-based alloy material is characterized by being made of a zinc-copper-magnesium alloy material or a zinc-magnesium-lithium alloy material, and comprising the following components in percentage by mass: 0 to 5 percent of copper, 0.01 to 0.1 percent of magnesium, 0 to 0.5 percent of lithium and the balance of zinc.

2. The degradable vascular stent made of zinc-based alloy material according to claim 1, wherein the Cu content is controlled according to 1-5%, and the Mg content is controlled according to 0.01-0.05%; or the Cu content is controlled according to 0.1-1 percent, and the Mg content is controlled according to 0.05-0.1 percent; or the Li content is controlled according to 0 to 0.5 percent, the Mg content is controlled according to 0.01 to 0.05 percent, and the rest is the zinc content; wherein, the zinc alloy raw materials adopt: pure zinc, the purity of which is more than 99.995%; pure copper, with a purity of greater than 99.995%; pure lithium, the purity of which is more than 99.95%; the zinc-magnesium intermediate alloy has a magnesium content of 2-10%.

3. The degradable vascular stent made of zinc-based alloy material according to claim 1, wherein the zinc alloy comprises the following components: zn- (1-5%) Cu- (0.01-0.05%) Mg; or Zn- (0.1-1%) Cu- (0.05-0.1%) Mg; or Zn- (0-0.5%) and Li- (0.01-0.05%) as Mg.

4. A method for preparing a degradable vascular stent made of zinc-based alloy material according to any one of claims 1 to 3, which is characterized by comprising the following steps:

s1, smelting zinc alloy: the zinc alloy is obtained by smelting, component adjustment, filtration and casting of a pure zinc ingot;

s2, homogenizing heat treatment: heating and preserving the temperature of the extruded blank, and then cooling the extruded blank along with the furnace;

s3, preheating and extruding: heating and insulating the extruded blank, and extruding the blank into a bar;

s4, subsequent processing: and drilling and polishing the bar stock to obtain the degradable zinc alloy intravascular stent.

5. The method for preparing the degradable intravascular stent made of the zinc-based alloy material according to claim 4, wherein in the smelting process of the zinc alloy in S1, all melt contact surfaces are made of high-purity graphite or boron nitride materials, the melt is filtered by a graphite filter, non-metallic impurities in the melt are effectively adsorbed and intercepted in the filtering process, the quality of the filtered melt is ensured, and the zinc alloy melt is cast by a grinding tool and then molded to finally prepare an extrusion blank with the diameter of 45-50mm and the height of 110-150 mm.

6. The method for preparing the degradable vascular stent made of the zinc-based alloy material according to claim 4, wherein the smelting process of the zinc alloy in S1 is as follows: and (2) putting the zinc alloy into a vacuum melting furnace, heating the metal to 550-660 ℃, preserving the heat, adding metal elements such as Cu, Mg, Li and the like after the temperature reaches a point, uniformly stirring, reheating the melt to 550-660 ℃, and standing for 0.5-2 h.

7. The method for preparing the degradable vascular stent made of the zinc-based alloy material according to claim 4, wherein the homogenization heat treatment process in the step S2 is as follows: heating the extrusion blank to 250-380 ℃, preserving heat for 5-72 hours, cooling along with the furnace, and removing 1-2mm oxide skin on the surface of the cooled extrusion blank by using a lathe.

8. The method for preparing the degradable vascular stent made of the zinc-based alloy material according to claim 4, wherein the preheating and extruding process in the step S3 is as follows: heating the extrusion blank to 150-350 ℃, and preserving heat for 2-5 hours, wherein the speed of the extrusion process is controlled to be 20-50 mm/min, and the extrusion ratio is controlled to be 12: 1-15: 1, rapidly cooling an extrusion outlet by using strong wind, and extruding into a bar with the external diameter phi of 11-13 mm.

9. The method for preparing the degradable vascular stent made of the zinc-based alloy material according to the claim 4, wherein the subsequent treatment process in the step S4 comprises the following steps of straightening and polishing: and polishing by using a grinding machine, wherein the polished rod material has an outer diameter of 11-12 mm, a roundness of less than 0.02mm and a parallelism of less than 0.02 mm.

10. The method for preparing the degradable vascular stent made of the zinc-based alloy material according to the claim 9, wherein the subsequent processing process in the S4 comprises drilling and drawing: and drilling the extruded bar, drawing to obtain a pipe with the wall thickness of 0.1-1.5 mm, and performing laser engraving, polishing, spraying and pressing on the pipe to obtain the degradable zinc alloy intravascular stent.

Technical Field

The invention relates to the technical field of medical degradable materials, in particular to a degradable intravascular stent made of zinc-based alloy materials and a preparation method thereof.

Background

Generally, under the influence of the traditional Ti alloy intravascular stent, the existing intravascular stent is difficult to degrade in vivo, so that the stent needs to be taken out at intervals after being implanted, the non-degradable stent is remained in vivo for a long time to cause inflammation, and the degradable stent material can effectively avoid the problems of biological inflammation, biomechanical incompatibility and the like in vivo caused by long-term implantation of instruments in vivo, so that the degradable zinc alloy intravascular stent has wide market prospect and good medical value.

Disclosure of Invention

The invention provides a degradable vascular stent made of zinc-based alloy materials and a preparation method thereof, and aims to solve the problems of biological inflammation and biomechanical incompatibility in vivo and incapability of degradation in vivo caused by long-term implantation of instruments in vivo in the background art.

In order to achieve the above object, the degradable vascular stent made of a zinc-based alloy material provided by the embodiment of the present invention is a degradable vascular stent made of a zinc-copper-magnesium alloy material or a zinc-magnesium-lithium alloy material, and the degradable vascular stent is prepared from the following components by mass: 0 to 5 percent of copper, 0.01 to 0.1 percent of magnesium, 0 to 0.5 percent of lithium and the balance of zinc.

Wherein, the content of Cu is controlled according to 1 to 5 percent, and the content of Mg is controlled according to 0.01 to 0.05 percent; or the Cu content is controlled according to 0.1-1 percent, and the Mg content is controlled according to 0.05-0.1 percent; or the Li content is controlled according to 0 to 0.5 percent, the Mg content is controlled according to 0.01 to 0.05 percent, and the rest is the zinc content; wherein, the zinc alloy raw materials adopt: pure zinc, the purity of which is more than 99.995%; pure copper, with a purity of greater than 99.995%; pure lithium, the purity of which is more than 99.95%; the zinc-magnesium intermediate alloy has a magnesium content of 2-10%.

Wherein the zinc alloy comprises the following components: zn- (1-5%) Cu- (0.01-0.05%) Mg; or Zn- (0.1-1%) Cu- (0.05-0.1%) Mg; or Zn- (0-0.5%) and Li- (0.01-0.05%) as Mg.

The embodiment of the invention provides a preparation method of a degradable vascular stent made of zinc-based alloy materials, which comprises the following steps:

s1, smelting zinc alloy: the zinc alloy is obtained by smelting, component adjustment, filtration and casting of a pure zinc ingot;

s2, homogenizing heat treatment: heating and preserving the temperature of the extruded blank, and then cooling the extruded blank along with the furnace;

s3, preheating and extruding: heating and insulating the extruded blank, and extruding the blank into a bar;

s4, subsequent processing: and drilling and polishing the bar stock to obtain the degradable zinc alloy intravascular stent.

In the zinc alloy smelting process in S1, all the contact surfaces of the molten metal are made of high-purity graphite or boron nitride materials, the molten metal is filtered by a graphite filter, the non-metallic impurities in the molten metal are effectively adsorbed and intercepted in the filtering process, the quality of the filtered molten metal is guaranteed, and the zinc alloy molten metal is cast by a grinding tool and then molded to finally prepare an extrusion blank with the diameter of 45-50mm and the height of 110-150 mm.

The smelting process of the zinc alloy in the S1 comprises the following steps: and (2) putting the zinc alloy into a vacuum melting furnace, heating the metal to 550-660 ℃, preserving the heat, adding metal elements such as Cu, Mg, Li and the like after the temperature reaches a point, uniformly stirring, reheating the melt to 550-660 ℃, and standing for 0.5-2 h.

Wherein the homogenization heat treatment process in the step S2 is as follows: heating the extrusion blank to 250-380 ℃, preserving heat for 5-72 hours, cooling along with the furnace, and removing 1-2mm oxide skin on the surface of the cooled extrusion blank by using a lathe.

Wherein the preheating extrusion process in the step S3 is as follows: heating the extrusion blank to 150-350 ℃, and preserving heat for 2-5 hours, wherein the speed of the extrusion process is controlled to be 20-50 mm/min, and the extrusion ratio is controlled to be 12: 1-15: 1, rapidly cooling an extrusion outlet by using strong wind, and extruding into a bar with the external diameter phi of 11-13 mm.

Wherein the subsequent treatment process in the step S4 comprises straightening and polishing: and polishing by using a grinding machine, wherein the polished rod material has an outer diameter of 11-12 mm, a roundness of less than 0.02mm and a parallelism of less than 0.02 mm.

Wherein the subsequent processing process in S4 includes drilling and drawing: and drilling the extruded bar, and drawing to obtain a pipe with the wall thickness of 0.1-1.5 mm, thereby obtaining the raw material of the support.

The degradable zinc alloy intravascular stent is obtained by performing laser engraving, polishing, spraying and pressing on the pipe.

The scheme of the invention has the following beneficial effects:

the method is adjusted from the aspects of melt quality, alloy proportion, extrusion process and the like of the zinc-based alloy, can prepare the degradable intravascular stent tubing with the tensile strength of 300-450 MPa and the elongation rate of more than 15%, has moderate degradation rate, and has no harm to production of degradation products, thereby solving the problems of insufficient mechanical property, slow degradation speed and the like of the zinc-based alloy intravascular stent and effectively improving the stability of the zinc-based alloy intravascular stent in the degradation process.

Drawings

FIG. 1 is a flow chart of the preparation method of the degradable vascular stent made of zinc-based alloy material of the invention.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

Aiming at the existing problems, the invention provides a zinc-based alloy material degradable intravascular stent which is made of a zinc-copper-magnesium alloy material or a zinc-magnesium-lithium alloy material, and the zinc-copper-magnesium alloy material or the zinc-magnesium-lithium alloy material comprises the following components in percentage by mass: 0 to 5 percent of copper, 0.01 to 0.1 percent of magnesium, 0 to 0.5 percent of lithium and the balance of zinc.

The Cu content is controlled according to 1-5%, and the Mg content is controlled according to 0.01-0.05%; or the Cu content is controlled according to 0.1-1 percent, and the Mg content is controlled according to 0.05-0.1 percent; or the Li content is controlled according to 0 to 0.5 percent, the Mg content is controlled according to 0.01 to 0.05 percent, and the rest is the zinc content; wherein, the zinc alloy raw materials adopt: pure zinc, the purity of which is more than 99.995%; pure copper, with a purity of greater than 99.995%; pure lithium, the purity of which is more than 99.95%; the zinc-magnesium intermediate alloy has a magnesium content of 2-10%.

The zinc alloy comprises the following components: zn- (1-5%) Cu- (0.01-0.05%) Mg; or Zn- (0.1-1%) Cu- (0.05-0.1%) Mg; or Zn- (0-0.5%) and Li- (0.01-0.05%) as Mg.

The invention provides a preparation method of a degradable intravascular stent made of zinc-based alloy materials, which comprises the following steps:

s1, smelting zinc alloy: the zinc alloy is obtained by smelting, component adjustment, filtration and casting of a pure zinc ingot;

specifically, all melt contact surfaces in the smelting process adopt high-purity graphite or boron nitride materials, the melt is filtered by a graphite filter, the filtering process effectively adsorbs and intercepts non-metallic impurities in the melt, the quality of the filtered melt is ensured, and the zinc alloy melt is cast by a grinding tool and then is molded to finally prepare an extrusion blank with the diameter of 45-50mm and the height of 110-150 mm;

the zinc alloy smelting process comprises the following steps: and (2) putting the zinc alloy into a vacuum melting furnace, heating the metal to 550-660 ℃, preserving the heat, adding metal elements such as Cu, Mg, Li and the like after the temperature reaches a point, uniformly stirring, reheating the melt to 550-660 ℃, and standing for 0.5-2 h.

S2, homogenizing heat treatment: heating and preserving the temperature of the extruded blank, and then cooling the extruded blank along with the furnace;

specifically, the extrusion blank is heated to 250-380 ℃, heat preservation is carried out for 5-72 hours, the extrusion blank is cooled along with a furnace, and oxide skins with the surface of 1-2mm are removed from the cooled extrusion blank by a lathe.

S3, preheating and extruding: heating and insulating the extruded blank, and extruding the blank into a bar;

specifically, heating an extrusion blank to 150-350 ℃, and preserving heat for 2-5 hours, wherein the speed of the extrusion process is controlled to be 20-50 mm/min, and the extrusion ratio is controlled to be 12: 1-15: 1, rapidly cooling an extrusion outlet by using strong wind, and extruding into a bar with the external diameter phi of 11-13 mm.

S4, subsequent processing: drilling and polishing the bar stock to obtain the degradable zinc alloy intravascular stent;

specifically, the subsequent treatment process comprises straightening and polishing: and polishing by using a grinding machine, wherein the polished rod material has an outer diameter of 11-12 mm, a roundness of less than 0.02mm and a parallelism of less than 0.02 mm.

The subsequent treatment process comprises drilling and drawing: and drilling the extruded bar, drawing to obtain a pipe with the wall thickness of 0.1-1.5 mm, and performing laser engraving, polishing, spraying and pressing on the pipe to obtain the degradable zinc alloy intravascular stent.