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CN-117340550-B - Ultrathin degradable Fe-Se alloy bracket and preparation method thereof

CN117340550BCN 117340550 BCN117340550 BCN 117340550BCN-117340550-B

Abstract

The invention discloses an ultrathin degradable Fe-Se alloy bracket and a preparation method thereof, wherein Fe particles and Fe-Se intermediate alloy powder are prepared, fe-Se cast ingots are obtained by smelting, the Fe-Se cast ingots are cast in a mould after being melted, fe-Se bar materials are obtained, the Fe-Se bar materials are annealed to obtain annealed bar blanks, the annealed bar blanks are extruded to obtain extruded bar blanks, the extruded bar blanks are subjected to multi-pass drawing to obtain Fe-Se pipe materials, and the Fe-Se pipe materials are processed to obtain the Fe-Se alloy bracket.

Inventors

  • ZHANG DECHUANG
  • DENG BO
  • LIN JIANGUO
  • GUO LIN
  • HUANG JUNMING
  • ZHANG MIAO

Assignees

  • 湘潭大学

Dates

Publication Date
20260505
Application Date
20231008

Claims (6)

  1. 1. The preparation method of the ultrathin degradable Fe-Se alloy bracket is characterized by comprising the steps of preparing Fe particles and Fe-Se intermediate alloy powder, smelting to obtain Fe-Se ingots, pouring the Fe-Se ingots into a mould after melting to obtain Fe-Se bars, annealing the Fe-Se bars to obtain annealed bars, extruding the annealed bars to obtain extruded bars, drawing the extruded bars for multiple times to obtain Fe-Se pipes, and processing the Fe-Se pipes to obtain the Fe-Se alloy bracket, wherein the mass fraction of Se in the Fe-Se alloy bracket is 0.1-2.0 wt%; The temperature of the annealing treatment is 600-800 ℃, and the time of the annealing treatment is 20-30min; After the annealing treatment, carrying out water quenching; preheating an annealing bar blank at 550-600 ℃ for 45-60min, and then performing hot extrusion, wherein the temperature of the hot extrusion is 550-620 ℃, the extrusion ratio is 10-25:1, and the extrusion speed is 1-2mm/s; The multi-pass drawing process comprises preheating for 15-30min at 500-550 ℃, air cooling, drawing, and heat treatment between the passes, wherein the temperature of the heat treatment between the last pass is 600-650 ℃, the temperature of the heat treatment between the other passes is 500-550 ℃, and the time of the heat treatment between the passes is 15-30min; when the multi-pass drawing is performed, the single-pass deformation is controlled to be 15% -20%, and the total deformation is less than or equal to 90%.
  2. 2. The method for preparing the ultrathin degradable Fe-Se alloy bracket is characterized in that an iron foil is wrapped on Fe-Se intermediate alloy powder, the Fe particles are placed on the Fe-Se intermediate alloy powder in a vacuum arc melting furnace, the Fe particles are covered on the Fe-Se intermediate alloy powder, the Fe particles are melted by using 90-100A current to obtain Fe liquid, the Fe intermediate alloy powder below the Fe particles is wrapped, the current is increased to 150-250A, and the Fe intermediate alloy powder is repeatedly melted to obtain cast ingots, and the number of times of repeated melting is 6-8.
  3. 3. The method for preparing the ultrathin degradable Fe-Se alloy bracket, as set forth in claim 1 or 2, is characterized in that an Fe-Se cast ingot is placed at the edge of a pouring die in a vacuum arc melting furnace, arc striking is carried out, the current is increased to 250-300A, and the cast ingot is melted and poured in the die to obtain the Fe-Se bar.
  4. 4. The method for preparing the ultrathin degradable Fe-Se alloy bracket according to claim 1 or 2, which is characterized in that the Fe-Se alloy bracket is obtained by cutting and polishing a Fe-Se tube through laser.
  5. 5. The method for preparing an ultrathin degradable Fe-Se alloy bracket according to claim 1 or 2, wherein the wall thickness of the Fe-Se alloy bracket is less than or equal to 80 mu m, In the Fe-Se alloy bracket, the mass fraction of Se is 0.5-1.2wt%.
  6. 6. The Fe-Se alloy stent prepared by the preparation method of any one of claims 1 to 5.

Description

Ultrathin degradable Fe-Se alloy bracket and preparation method thereof Technical Field The invention belongs to the technical field of biomedical iron-based alloy, and particularly relates to an ultrathin degradable Fe-Se alloy bracket and a preparation method thereof. Background The degradable ferroalloy has great application potential in the field of medical appliances implanted in hard tissues of human body due to excellent biocompatibility and functionality. Iron (Fe) is a trace element essential for the human body and is involved in the synthesis of oxygen transport proteins (hemoglobin and myoglobin), the composition of functional enzymes, immunomodulation, electron transport, the formation of heme and iron binding enzymes, and maintenance of normal hematopoietic function. The Fe content and RDI in human body were about 3-5g and 0.9mg, respectively, and the IC50 for endothelial cells was 66.7mM at 6.3-26.9. Mu.M in plasma. Absorbable stents are considered the fourth revolution in cardiovascular intervention. As one of the main materials of the absorbable vascular stent, compared with polymers and magnesium-based alloys, the pure iron has the advantages of greatly improving the strength by modification, and has the inherent disadvantages of slow corrosion and absorption in vivo, and the reason and mechanism of the slow absorption are not clear. Therefore, the mechanical properties equivalent to those of the permanent stent are achieved by using the minimum iron and the thinnest wall thickness, and meanwhile, the in-vivo degradation curve is matched with the healing time of the diseased blood vessel of the human body, so that the fully absorbed blood vessel can be fully absorbed as soon as possible after the fully degraded blood vessel is completely degraded. The existing method for improving the degradation rate of pure iron mainly comprises (1) adding alloying elements except noble metals, such as Mn, co, C, B, S and the like, in the solubility range of iron, (2) adding noble metal alloying elements to generate fine and dispersed metal intermediate phases which act as cathodes relative to an iron matrix to cause microcurrent corrosion so as to improve the degradation rate, (3) introducing a pore structure into the iron matrix to improve the degradation rate by increasing the contact effective area with corrosive environment, but because iron has ferric oxide and ferric hydroxide corrosion products in the degradation process, further corrosion is prevented, and thus the degradation rate cannot be obviously improved by only preparing porous iron. By adding proper alloying elements, the degradation rate of the alloy is expected to be improved, and the mechanical property and biocompatibility of the alloy can be improved, so that the alloy is a promising approach. Selenium (Se) is one of microelements necessary for human body, and can form glutathione peroxidase, protect cell tissue, maintain cell membrane function, and play an antioxidant role. Selenium has strong binding force with metal, and can resist toxicity of cadmium to kidney, gonad and central nerve. Selenium is used as non-metal ion with negative charge, and can combine with harmful metal ion with positive charge in living body to form metal selenium protein complex, and the harmful metal ion capable of inducing canceration is directly discharged out of body, so that the toxicity of metal ion is counteracted, and the functions of detoxification and detoxification are achieved. In addition, the selenium content in blood is closely related to the occurrence of cancers, selenium can reduce the toxicity of aflatoxin (which can induce liver cancer), and the risk of cancers is small if the selenium content in the body is high, so that the risk of cancers can be reduced by selenium. In addition, selenium can also reduce the occurrence risk of diabetes, cataract and other diseases, maintain muscular nutrition and reduce the incidence rate of white muscle disease. According to the solid solution theory of Fe-Se alloy phase diagram, the formation of Se-rich precipitate in the matrix is expected to induce microelectric corrosion, so that the degradation rate is greatly improved, and Se ions have anti-tumor performance from the biological point of view and do not cause direct and serious risks to human health. From the phase diagram, it is known that Fe has a melting point of 1538 ℃ and Se has a melting point of 220 ℃ and a boiling point of 685 ℃, the melting point and boiling temperature are low, the volatility is large, the solubility is difficult, and more importantly, fe and Se have far different melting points and poor solid solution capacity. In the prior art, no ultrathin biodegradable Fe-Se alloy material is reported so far. Disclosure of Invention Aiming at the defects existing in the prior art, the first aim of the invention is to provide a preparation method of an ultrathin degradable Fe-Se alloy bracket, wherein the ultrathin degradable Fe-Se