Smelting method of medical austenitic stainless steel

Abstract

The invention relates to the technical field of metal refining, and particularly discloses a smelting method of medical austenitic stainless steel. The smelting method of the medical austenitic stainless steel comprises the following steps: S1, primary smelting of alloy furnace raw materials; s2, AOD furnace operation is conducted, specifically, molten steel is mixed into the AOD furnace, oxygen blowing decarburization is started, reduced lime and silicon iron are added to a certain degree for deoxidation and slagging, and alloy components are finely adjusted after the molten steel is reduced; s3, LF operation, wherein after molten steel enters an LF furnace, power is supplied to adjust the temperature; in the process, a spectrograph is used for analyzing component results, and argon impurities are softly blown after components are adjusted to meet requirements; and S4, continuous casting operation is conducted, specifically, after the steel ladle is lifted to a continuous casting rotary table, molten steel enters a tundish through a water gap in the bottom of the steel ladle, the molten steel enters three crystallizers after being distributed by the tundish, and the molten steel is solidified in the crystallizers to produce continuous casting billets. The austenitic stainless steel can be used for medical research, and has the advantages of improving the recovery rate of raw materials, reducing the cost of the raw materials and the like.

Description

Technical Field

[0001] The present application relates to the technical field of metal refining, and more specifically, to a method for smelting medical austenitic stainless steel. Background Art

[0002] Metal refining is of great significance in industrial development. In many fields, especially in the medical field, the quality and performance requirements of metal materials are extremely high. When producing stainless steel, traditional metal refining methods may have the problem of difficult to accurately control the impurity content, which will affect key indicators such as corrosion resistance and mechanical properties of stainless steel. Moreover, ordinary stainless steel often cannot fully meet the strict requirements of medical use in terms of biocompatibility, which may cause adverse reactions after implantation in the human body. In addition, some refining processes have low production efficiency and high costs, which are not conducive to the large-scale production of high-quality medical stainless steel.

[0003] The existing production process mainly adopts the production method of electric arc furnace + AOD furnace + die casting. This stainless steel smelting method not only has a low metal recovery rate and high raw material cost in electric furnace production, but also the die casting production has low efficiency and high production cost, and cannot be mass-produced. In addition, because the AOD molten steel is directly poured into the steel ingot, the product quality is poor.

[0004] Therefore, it is urgent to study a method for efficiently smelting medical austenitic stainless steel, which can also improve the metal recovery rate of electric furnace production, reduce raw material costs, and improve production efficiency and quality. Summary of the invention

[0005] In order to improve the strength and toughness of seamless steel pipes, the present application provides a method for smelting medical austenitic stainless steel, which adopts the following technical solution: The present application provides a method for smelting medical austenitic stainless steel, comprising the following steps: Alloy furnace smelting: stainless steel scrap and alloy iron are mixed in proportion and placed in an alloy furnace to melt into liquid steel; AOD furnace operation: After the primary molten steel is added into the AOD furnace, oxygen blowing and decarburization operation begins. When the carbon content in the molten steel is less than 0.08%, reducing lime and ferrosilicon are added to deoxidize and slag. After the molten steel is reduced, the alloy composition is fine-tuned. The steel is tapped when the composition meets the steel grade requirements. LF operation: After the molten steel arrives at the LF furnace, it is heated by electricity and the temperature of the molten steel is adjusted. During the power supply process, the molten steel sample is taken and the composition is analyzed by a spectrometer. According to the analysis results, the composition is adjusted again. When the temperature and composition meet the requirements, argon gas is soft-blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel. Continuous casting operation: After the ladle is hoisted onto the continuous casting turntable, the molten steel enters the tundish through the water inlet at the bottom of the ladle. After being distributed in the tundish, the molten steel enters three crystallizers respectively. The molten steel solidifies in the crystallizer to produce continuous casting billets.

[0006] By adopting the above technical solution, firstly, stainless steel scrap and alloy iron are mixed in proportion and then put into an alloy furnace to melt into liquid molten steel. The alloy furnace is used to replace the electric arc furnace as the primary smelting furnace for raw materials, thereby improving the recovery rate of raw materials and reducing the cost of raw materials. Secondly, after the primary molten steel is added into the AOD furnace, oxygen blowing and decarburization operation is started. When the carbon content in the molten steel is within 0.08%, reducing lime and ferrosilicon are added for deoxidation and slag making. After the molten steel is reduced, the alloy composition is fine-tuned. When the composition meets the requirements of the steel grade, the steel is discharged; after the molten steel reaches the LF furnace, power is supplied to increase the temperature and adjust the temperature of the molten steel; during the power supply process, a sample of the molten steel is taken, and the composition is analyzed by a spectrometer. According to the analysis results, the composition is adjusted again; when the temperature and composition meet the requirements at the same time, Soft blowing of argon removes deoxidation inclusions in the molten steel and improves the purity of the molten steel. After the AOD is tapped, it goes to the LF furnace to stably control the temperature and composition of the molten steel. Through the soft blowing operation, the purity of the molten steel is controlled, and the internal quality of the product is improved through the refining operation of the LF furnace. Finally, after the ladle is hoisted to the continuous casting turntable, the molten steel enters the tundish through the water inlet at the bottom of the ladle. After the molten steel is distributed in the tundish, it enters three crystallizers respectively. The molten steel solidifies in the crystallizer to produce continuous casting billets. The continuous casting method replaces the mold casting method, which improves production efficiency and product quality, achieves the purpose of mass production, and reduces production costs.

[0007] Optionally, the austenitic stainless steel further includes inorganic particles, and the inorganic particles include C, Cr, Ni, Mn, Mo, Cu, Si, N and Nb.

[0008] By adopting the above technical solutions, inorganic particles can be used as strengthening phases to hinder dislocation movement, thereby improving the strength of austenitic stainless steel. For example, carbide particles formed by carbide-forming elements (such as Nb) can effectively enhance the strength of the material. Reasonable distribution of inorganic particles can prevent the expansion of cracks and improve the toughness of materials. For example, particles with good toughness can play a bridging role at the crack tip, absorb energy, and delay further expansion of cracks. Some inorganic particles (such as Cr, Mo, Ni, etc.) can promote the formation of dense oxide film or passivation film on the surface of the material, thereby improving the corrosion resistance of stainless steel. For example, the Cr element can form a stable Cr2O3 oxide film to prevent corrosive media from further eroding the material.

[0009] Optionally, the C≦0.08%, and the Cr=19.5%-22%.

[0010] By adopting the above technical solution, the lower carbon content can reduce the precipitation of carbides. In austenitic stainless steel, carbon easily combines with chromium to form carbides. When carbides precipitate at the grain boundaries, the chromium content near the grain boundaries will be reduced, thereby reducing the corrosion resistance of the stainless steel. Low carbon content can reduce this chromium depletion phenomenon and improve the corrosion resistance of the material, especially the resistance to intergranular corrosion. And chromium is one of the most important alloying elements in austenitic stainless steel. It can form a dense chromium oxide protective film to prevent corrosive media from contacting the metal matrix, thereby improving the corrosion resistance of stainless steel. A higher chromium content can enhance the stability and density of this protective film, so that stainless steel has good corrosion resistance in various corrosive environments, including in oxidizing acids, reducing acids and neutral media.

[0011] Optionally, Ni=9.0%-11.0%, Mn=2.0%-4.25% By adopting the above technical solution, nickel is a strong austenite stabilizing element. Nickel within this content range can effectively stabilize the austenite structure and prevent the stainless steel from undergoing phase transformation during the cooling process to form other phases such as martensite or ferrite, thereby ensuring that the material maintains good toughness and ductility at all temperatures. Manganese can improve the hot working properties and cold working properties of austenitic stainless steel. During hot working, manganese can reduce the hot working temperature range of the material and improve processing efficiency. During cold working, manganese can improve the plastic deformation capacity of the material, reduce work hardening, and facilitate cold working forming.

[0012] Optionally, during the alloy furnace smelting process, the electric arc furnace is replaced by the alloy furnace, and during the continuous casting process, the mold casting method is replaced by continuous casting.

[0013] By adopting the above technical solutions, alloy furnaces can generally use energy more efficiently and may consume less energy than arc furnaces. This helps reduce production costs and reduce environmental impact. Alloy furnaces can control alloy composition more accurately. Through precise batching and control of the melting process, the content of various elements in austenitic stainless steel can be ensured to be more accurate, thereby improving the quality stability of the product. Alloy furnaces usually have higher melting speeds and production capacities. Compared with arc furnaces, it can complete the melting process in a shorter time, thereby improving production efficiency and meeting the market demand for austenitic stainless steel. Continuous casting can achieve continuous production, which greatly shortens the production cycle compared to die casting. This makes the production of austenitic stainless steel faster and can meet the needs of large-scale production. Continuous casting can better control the solidification process of molten steel, thereby obtaining a more uniform structure and performance. Compared with die casting, the quality of austenitic stainless steel products produced by continuous casting is more stable and consistent.

[0014] Optionally, the AOD furnace operation refers to the oxygen blowing and decarburization operation starting after the primary molten steel is added into the AOD furnace. When the carbon content in the molten steel is within 0.08%, reducing lime and ferrosilicon are added for deoxidation and slag making. The alloy composition of the molten steel is fine-tuned after reduction, and the steel is discharged after the composition meets the requirements of the steel grade. The LF operation refers to the power supply and temperature increase of the molten steel after the molten steel arrives at the LF furnace, and the temperature of the molten steel is adjusted. During the power supply process, molten steel samples are taken, and the composition is analyzed by a spectrometer, and the composition is adjusted again according to the analysis results. When the temperature and composition meet the requirements at the same time, argon is soft-blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel.

[0015] By adopting the above technical scheme, the carbon content in the molten steel can be controlled within 0.08% through oxygen blowing and decarburization, meeting the requirements of austenitic stainless steel for low carbon content. This helps to improve the corrosion resistance of stainless steel, reduce the precipitation of carbides, and reduce the risk of intergranular corrosion. Adding reducing lime and ferrosilicon for deoxidation and slag making can effectively remove oxygen and impurities in the molten steel and improve the purity of the molten steel. The deoxidized molten steel has better fluidity, which is conducive to the subsequent casting and processing process. After the molten steel is reduced, the alloy composition can be fine-tuned to meet the requirements of the steel grade. This makes the production process more flexible, and the alloy formula can be adjusted according to different product requirements to produce austenitic stainless steel with various properties. Power transmission and heating can accurately adjust the temperature of the molten steel to reach the appropriate pouring temperature. Stable temperature control is crucial to ensure the quality of the ingot, which can reduce defects such as cracks and shrinkage cavities in the ingot. During the power transmission process, the molten steel sample is taken for spectrometer analysis of the composition, and the chemical composition of the molten steel can be understood in real time. Adjust the composition again according to the analysis results to ensure that the composition of the molten steel meets the requirements of the steel grade and improve the stability of product quality. Soft argon blowing can remove deoxidation inclusions in molten steel and further improve the purity of molten steel. Pure molten steel can reduce defects such as pores and slag inclusions in castings and improve the mechanical properties and corrosion resistance of stainless steel.

[0016] In summary, this application has the following beneficial effects: 1. Using alloy furnaces to replace traditional arc furnaces as primary smelting furnaces for raw materials. This change can significantly improve the recycling rate of raw materials. Compared with arc furnaces, alloy furnaces can more effectively utilize raw materials and reduce waste during the smelting process. This not only helps to reduce the company's raw material procurement costs, but also helps to improve the economic benefits of the entire production process. In addition, a higher raw material recovery rate is also beneficial to environmental protection and reduces the generation of industrial waste.

[0017] 2. The AOD furnace can effectively remove the carbon content in the molten steel to less than 0.08% through oxygen decarburization. This process not only removes carbon, but also removes other impurities, improving the purity of the molten steel. Adding reducing lime and ferrosilicon for deoxidation and slag making can further purify the molten steel and remove residual oxides and other non-metallic inclusions. Through the operation of the AOD furnace, the composition of the molten steel can be more accurately controlled. After the carbon content is reduced to less than 0.08%, reducing lime and ferrosilicon are added for deoxidation to ensure that the oxygen content in the molten steel is effectively controlled. After the molten steel is reduced, the alloy composition can be fine-tuned to ensure that the chemical composition of the final molten steel fully meets the requirements of the required steel grade.

[0018] 3. The LF furnace can accurately control the temperature of the molten steel. By supplying electricity to increase the temperature, the molten steel can be heated to the required temperature range to ensure the smooth progress of the subsequent processing. The accuracy of temperature control helps to improve the fluidity of the molten steel and reduce the solidification problem caused by insufficient temperature, thereby improving production efficiency and product quality. During the power supply process, the chemical composition of the molten steel can be monitored in real time by taking molten steel samples and using a spectrometer to analyze the composition. According to the analysis results, the composition can be adjusted in time to ensure that the final chemical composition of the molten steel meets the requirements of the required steel grade. This precise composition adjustment capability is crucial for the production of high-quality steel. The LF furnace operation process is compact and efficient, and can complete temperature adjustment and composition optimization in a relatively short time, thereby improving production efficiency.

[0019] 4. Using continuous casting technology to replace the traditional mold casting method for production can greatly improve the efficiency of the production line and the quality stability of the product. The continuous casting method can realize a continuous, fast and stable pouring process, avoiding various defects that may occur in the mold casting process, such as pores, cracks, etc. This method not only improves the yield rate, but also makes large-scale batch production possible, thereby reducing the average cost of a single product and enhancing the competitiveness of the product in the market. At the same time, due to the high degree of automation of the continuous casting process, it also reduces the manual operation links, further reducing production costs. DETAILED DESCRIPTION

[0020] Unless the context clearly dictates otherwise, unmodified nouns and nouns modified by "the" include singular and plural referents.

[0021] As used in the specification and claims, the terms "comprises," "comprising," "having," "may," "containing," and variations thereof as used herein refer to open transitional phrases, terms, or words that require the presence of specified ingredients / steps and allow for the presence of other ingredients / steps. However, such descriptions should be interpreted as also describing compositions or methods as "consisting of" and "consisting essentially of" the recited ingredients / steps, which allows for the presence of only the specified ingredients / steps and any unavoidable impurities that may result therefrom, and excludes other ingredients / steps.

[0022] Numerical values ​​in the specification and claims of this application should be understood to include the same numerical values ​​when reduced to the same number of significant figures and numerical values ​​that differ from the stated value by less than the experimental error of ordinary measurement techniques of the type described in this application for determining the stated value.

[0023] All ranges disclosed herein are inclusive of the indicated endpoints and are independently combinable (eg, the range of "2 grams to 10 grams" includes the endpoints 2 grams and 10 grams, and all intermediate values).

[0024] The terms "about" and "approximately" can be used to include any numerical value that can be varied without changing the basic function of the value. When used with a range, "about" and "approximately" also disclose the range defined by the absolute values ​​of the two endpoints, for example, "about 2 to about 4" also discloses a range of "2 to 4". Generally, the terms "about" and "approximately" can refer to ±10% of the indicated number. However, for temperature, the term "approximately" refers to ±1°C.

[0025] Unless expressly stated otherwise, the percentages of elements are to be considered as percentages by weight of the alloy in question.

[0026] The present disclosure may refer to the temperature of certain method steps. It should be noted that these indicators generally refer to the temperature set by the heat source (such as a furnace), and not necessarily the temperature that the heated material must reach.

[0027] The present invention provides a high-adsorbability resin for decarbonization with hydrogen peroxide and a preparation method thereof, comprising the following steps: S1, alloy furnace smelting; Stainless steel scrap and alloy iron are mixed in proportion and put into the alloy furnace to melt into liquid steel; S2, AOD furnace operation; After the primary molten steel is added into the AOD furnace, oxygen blowing and decarburization are started. When the carbon content in the molten steel is less than 0.08%, reducing lime and ferrosilicon are added to deoxidize and slag. After the molten steel is reduced, the alloy composition is fine-tuned. The steel is tapped when the composition meets the requirements of the steel grade. S3, LF operation; After the molten steel arrives at the LF furnace, power is supplied to increase the temperature and adjust the temperature of the molten steel. During the power supply process, a sample of the molten steel is taken and the composition is analyzed using a spectrometer. Based on the analysis results, the composition is adjusted again. When the temperature and composition meet the requirements at the same time, argon is soft-blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel. S4, continuous casting operation; After the ladle is hoisted to the continuous casting turntable, the molten steel enters the tundish through the water inlet at the bottom of the ladle. After being distributed in the tundish, the molten steel enters three crystallizers respectively. The molten steel solidifies in the crystallizer to produce continuous casting billets. The specific steps are as follows: stainless steel scrap and alloy iron are mixed in proportion and put into the alloy furnace to melt into liquid molten steel. After the primary molten steel is added into the AOD furnace, oxygen blowing and decarburization operation are started. When the carbon content in the molten steel is within 0.08%, reducing lime and ferrosilicon are added for deoxidation and slag making. After the molten steel is reduced, the alloy composition is fine-tuned. After the composition meets the requirements of the steel grade, the steel is discharged. After the molten steel arrives at the LF furnace, power is supplied to increase the temperature and adjust the temperature of the molten steel. During the power supply process, molten steel samples are taken and the composition is analyzed using a spectrometer. According to the analysis results, the composition is adjusted again. When the temperature and composition meet the requirements at the same time, argon is softly blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel. After the ladle is hoisted to the continuous casting turntable, the molten steel enters the tundish through the water inlet at the bottom of the ladle. After the molten steel is distributed in the tundish, it enters three crystallizers respectively. The molten steel solidifies in the crystallizer to produce continuous casting billets. S1, alloy furnace smelting; Stainless steel scrap and alloy iron are mixed in proportion and put into the alloy furnace to melt into liquid steel; S2, AOD furnace operation; After the primary molten steel is added into the AOD furnace, oxygen blowing and decarburization are started. When the carbon content in the molten steel is less than 0.08%, reducing lime and ferrosilicon are added to deoxidize and slag. After the molten steel is reduced, the alloy composition is fine-tuned. The steel is tapped when the composition meets the requirements of the steel grade. S3, LF operation; After the molten steel arrives at the LF furnace, power is supplied to increase the temperature and adjust the temperature of the molten steel. During the power supply process, a sample of the molten steel is taken and the composition is analyzed using a spectrometer. Based on the analysis results, the composition is adjusted again. When the temperature and composition meet the requirements at the same time, argon is soft-blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel. S4, continuous casting operation; After the ladle is hoisted to the continuous casting turntable, the molten steel enters the tundish through the water inlet at the bottom of the ladle. After being distributed in the tundish, the molten steel enters three crystallizers respectively. The molten steel solidifies in the crystallizer to produce continuous casting billets. The specific steps are as follows: stainless steel scrap and alloy iron are mixed in proportion and put into an alloy furnace to melt into liquid molten steel. After the primary molten steel is added into the AOD furnace, oxygen blowing and decarburization operation are started. When the carbon content in the molten steel is within 0.08%, reducing lime and ferrosilicon are added for deoxidation and slag making. After the molten steel is reduced, the alloy composition is fine-tuned. After the composition meets the requirements of the steel grade, the steel is discharged. After the molten steel arrives at the LF furnace, power is supplied to increase the temperature and adjust the temperature of the molten steel. During the power supply process, molten steel samples are taken and the composition is analyzed using a spectrometer. According to the analysis results, the composition is adjusted again. When the temperature and composition meet the requirements at the same time, argon is softly blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel. After the ladle is hoisted to the continuous casting turntable, the molten steel enters the tundish through the water inlet at the bottom of the ladle. After the molten steel is distributed in the tundish, it enters three crystallizers respectively. The molten steel solidifies in the crystallizer to produce continuous casting billets.

[0028] S1, alloy furnace smelting; Stainless steel scrap and alloy iron are mixed in proportion and put into the alloy furnace to melt into liquid steel; S2, AOD furnace operation; After the primary molten steel is added into the AOD furnace, oxygen blowing and decarburization are started. When the carbon content in the molten steel is less than 0.08%, reducing lime and ferrosilicon are added to deoxidize and slag. After the molten steel is reduced, the alloy composition is fine-tuned. The steel is tapped when the composition meets the requirements of the steel grade. S3, LF operation; After the molten steel arrives at the LF furnace, power is supplied to increase the temperature and adjust the temperature of the molten steel. During the power supply process, a sample of the molten steel is taken and the composition is analyzed using a spectrometer. Based on the analysis results, the composition is adjusted again. When the temperature and composition meet the requirements at the same time, argon is soft-blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel. S4, continuous casting operation; After the ladle is hoisted to the continuous casting turntable, the molten steel enters the tundish through the water inlet at the bottom of the ladle. After being distributed in the tundish, the molten steel enters three crystallizers respectively. The molten steel solidifies in the crystallizer to produce continuous casting billets. The specific steps are as follows: stainless steel scrap and alloy iron are mixed in proportion and put into an alloy furnace to melt into liquid molten steel. After the primary molten steel is added into the AOD furnace, oxygen blowing and decarburization operation are started. When the carbon content in the molten steel is within 0.08%, reducing lime and ferrosilicon are added for deoxidation and slag making. After the molten steel is reduced, the alloy composition is fine-tuned. After the composition meets the requirements of the steel grade, the steel is discharged. After the molten steel arrives at the LF furnace, power is supplied to increase the temperature and adjust the temperature of the molten steel. During the power supply process, molten steel samples are taken and the composition is analyzed using a spectrometer. According to the analysis results, the composition is adjusted again. When the temperature and composition meet the requirements at the same time, argon is softly blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel. After the ladle is hoisted to the continuous casting turntable, the molten steel enters the tundish through the water inlet at the bottom of the ladle. After the molten steel is distributed in the tundish, it enters three crystallizers respectively. The molten steel solidifies in the crystallizer to produce continuous casting billets.

[0029] S1, alloy furnace smelting; Stainless steel scrap and alloy iron are mixed in proportion and put into the alloy furnace to melt into liquid steel; S2, AOD furnace operation; After the primary molten steel is added into the AOD furnace, oxygen blowing and decarburization are started. When the carbon content in the molten steel is less than 0.08%, reducing lime and ferrosilicon are added to deoxidize and slag. After the molten steel is reduced, the alloy composition is fine-tuned. The steel is tapped when the composition meets the requirements of the steel grade. S3, LF operation; After the molten steel arrives at the LF furnace, power is supplied to increase the temperature and adjust the temperature of the molten steel. During the power supply process, a sample of the molten steel is taken and the composition is analyzed using a spectrometer. Based on the analysis results, the composition is adjusted again. When the temperature and composition meet the requirements at the same time, argon is soft-blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel. S4, continuous casting operation; After the ladle is hoisted to the continuous casting turntable, the molten steel enters the tundish through the water inlet at the bottom of the ladle. After being distributed in the tundish, the molten steel enters three crystallizers respectively. The molten steel solidifies in the crystallizer to produce continuous casting billets. The specific steps are as follows: stainless steel scrap and alloy iron are mixed in proportion and put into an alloy furnace to melt into liquid molten steel. After the primary molten steel is added into the AOD furnace, oxygen blowing and decarburization operation are started. When the carbon content in the molten steel is within 0.08%, reducing lime and ferrosilicon are added for deoxidation and slag making. After the molten steel is reduced, the alloy composition is fine-tuned. After the composition meets the requirements of the steel grade, the steel is discharged. After the molten steel arrives at the LF furnace, power is supplied to increase the temperature and adjust the temperature of the molten steel. During the power supply process, molten steel samples are taken and the composition is analyzed using a spectrometer. According to the analysis results, the composition is adjusted again. When the temperature and composition meet the requirements at the same time, argon is softly blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel. After the ladle is hoisted to the continuous casting turntable, the molten steel enters the tundish through the water inlet at the bottom of the ladle. After the molten steel is distributed in the tundish, it enters three crystallizers respectively. The molten steel solidifies in the crystallizer to produce continuous casting billets.

[0030] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for smelting medical austenitic stainless steel, characterized in that: The following steps are involved: S1. Alloy furnace smelting: stainless steel scrap and alloy iron are mixed in proportion and placed in an alloy furnace to melt into liquid steel; S2, AOD furnace operation: After the primary molten steel is added into the AOD furnace, oxygen blowing and decarburization operation begins. When the carbon content in the molten steel is less than 0.08%, reducing lime and ferrosilicon are added to deoxidize and slag. After the molten steel is reduced, the alloy composition is fine-tuned. The steel is tapped when the composition meets the steel grade requirements. S3, LF operation: After the molten steel arrives at the LF furnace, power is supplied to increase the temperature and adjust the temperature of the molten steel; during the power supply process, the molten steel sample is taken and the composition is analyzed using a spectrometer. According to the analysis results, the composition is adjusted again; when the temperature and composition meet the requirements at the same time, argon is soft-blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel; S4. Continuous casting operation: After the ladle is hoisted to the continuous casting turntable, the molten steel enters the tundish through the water inlet at the bottom of the ladle. After being distributed by the tundish, the molten steel enters three crystallizers respectively. The molten steel solidifies in the crystallizer to produce continuous casting billets.

2. The method for smelting medical austenitic stainless steel according to claim 1, characterized in that: The austenitic stainless steel further includes inorganic particles including C, Cr, Ni, Mn, Mo, Cu, Si, N, and Nb.

3. The method for smelting medical austenitic stainless steel according to claim 2, characterized in that: The C≦0.08%, and the Cr=19.5%-22%.

4. The method for smelting medical austenitic stainless steel according to claim 1, characterized in that: The Ni=9.0%-11.0%, and the Mn=2.0%-4.25%.

5. The method for smelting medical austenitic stainless steel according to claim 1, characterized in that: In the alloy furnace smelting process, the alloy furnace replaces the electric arc furnace, and in the continuous casting process, the continuous casting method replaces the mold casting method.

6. The method for smelting medical austenitic stainless steel according to claim 1, characterized in that: The AOD furnace operation refers to the oxygen blowing and decarburization operation after the primary molten steel is added into the AOD furnace. When the carbon content in the molten steel is within 0.08%, reducing lime and ferrosilicon are added for deoxidation and slag making. The alloy composition of the molten steel is fine-tuned after reduction, and the steel is discharged after the composition meets the requirements of the steel grade. The LF operation refers to the power supply and temperature increase after the molten steel arrives at the LF furnace to adjust the temperature of the molten steel; take molten steel samples during the power supply process, use a spectrometer to analyze the composition, and adjust the composition again based on the analysis results; when the temperature and composition meet the requirements at the same time, soft argon is blown to remove deoxidation inclusions in the molten steel and improve the purity of the molten steel.