Martensitic stainless steel suture needle, preparation method thereof and ion nitriding tool for suture needle

Abstract

The invention relates to the technical field of medical suture needle surface treatment, and particularly discloses a martensitic stainless steel suture needle, a preparation method thereof and an ion nitriding tool for the suture needle. The martensitic stainless steel suture needle comprises a needle tail, a needle body and a needle tip, the preparation method comprises the following steps: processing and molding the martensitic stainless steel wire, and polishing to obtain the suture needle with the needle tip, the needle body and the needle tail; the suture needle is placed in the ion nitriding tool for the suture needle, the needle tip of the suture needle is inserted into the nitriding hole, the needle tail is inserted into the limiting hole, and a tool for assembling the suture needle is obtained; and after a tool for assembling the suture needle is subjected to surface nitriding treatment in the environment of nitrogen and hydrogen, the suture needle is cleaned and dried, and the martensitic stainless steel suture needle subjected to surface nitriding treatment is obtained. According to the preparation method of the martensitic stainless steel suture needle, the hardness and sharpness of the suture needle are remarkably improved, the contradiction between high hardness and high toughness of the suture needle is solved, and the applicability of the suture needle is favorably expanded.

Description

Technical Field

[0001] The present application relates to the technical field of surface treatment of medical suture needles, and more specifically, to a martensitic stainless steel suture needle and a preparation method thereof, and an ion nitriding tool for the suture needle. Background Art

[0002] Medical stainless steel is an alloy material. Due to its advantages such as good biocompatibility, mechanical properties, corrosion resistance and processing performance, medical stainless steel has been widely used in the manufacture of various medical devices, such as scalpels, tweezers, forceps and suture needles.

[0003] Medical suture needles are small medical devices used in surgical operations. Their main function is to suture the wound tissue of the human body together. The stainless steel used in medical suture needles mainly includes martensitic stainless steel and austenitic stainless steel. The raw material of martensitic stainless steel suture needles is soft steel wire, which has good processing performance.

[0004] However, after the steel wire is processed into a suture needle of a specific shape, although the toughness of the suture needle can be improved through low-temperature tempering treatment (heating temperature ≤ 250°C), part of the martensitic structure is eliminated, so the hardness of the suture needle is also reduced, making it difficult to meet the requirements for needle tip hardness (≥HV520) in the Chinese pharmaceutical industry medical suture needle standard (YY / T 0043-2016). Summary of the invention

[0005] In order to improve the hardness of a martensitic stainless steel suture needle, the present application provides a martensitic stainless steel suture needle, a preparation method thereof, and an ion nitriding tool for the suture needle.

[0006] In a first aspect, the present application provides an ion nitriding tool for a suture needle, which adopts the following technical solution: An ion nitriding tool for a suture needle comprises a cathode needle placement plate and an anode nitriding plate, wherein the cathode needle placement plate is connected to the negative pole of a power supply, the anode nitriding plate is located on the top of the cathode needle placement plate and is connected to the positive pole of the power supply, a nitriding hole for accommodating the needle tip of the suture needle is provided on the surface of the anode nitriding plate, and a limited position hole for accommodating the needle tail of the suture needle is provided on the surface of the cathode needle placement plate.

[0007] Ion nitriding is an important surface nitriding technology. In the ion nitriding process, the furnace body acts as the anode and the workpiece to be treated acts as the cathode, and a DC voltage of several hundred volts is applied between the two. Under this voltage, the gas (mainly nitrogen and hydrogen) in the furnace body will undergo a glow discharge phenomenon, thereby forming a plasma. The nitrogen molecules in it are ionized under the bombardment of high-energy electrons to form nitrogen atoms and nitrogen ions, which move to the surface of the workpiece at a high speed under the action of the electric field and react chemically with the carbon atoms on the surface of the workpiece to form nitrides (such as iron nitride, chromium nitride, etc.). These nitrides form a dense nitride layer on the surface of the workpiece, thereby improving the hardness, wear resistance and corrosion resistance of the workpiece surface.

[0008] By adopting the above technical solution, after the suture needle is fixed with a tool, the ion nitriding furnace is turned on for ion nitriding. At this time, a large amount of nitrogen-containing gas is filled in the nitriding hole. These gases are ionized under the action of DC high voltage to form nitrogen plasma, which is positively charged and can be accelerated toward the cathode under the action of the DC electric field, thereby quickly penetrating into the needle tip connected to the cathode to improve the hardness of the needle tip. At the same time, since the ion nitriding tool for the suture needle of the present application is a local nitriding tool, the needle tip of the suture needle can be nitrided, so while achieving the goal of improving the hardness of the needle tip, the elasticity and toughness of the needle body and the needle tail are also maintained.

[0009] Preferably, the aperture of the nitriding hole gradually decreases from the side close to the cathode needle plate to the side away from the cathode needle plate, and the aperture of the limiting hole gradually decreases from the side close to the anode nitriding plate to the side away from the anode nitriding plate.

[0010] By adopting the above technical solution, the aperture setting of the nitriding hole and the limiting hole can meet the placement requirements of suture needles of different diameters. At the same time, when the needle tip is placed in the nitriding hole during nitriding, it does not contact the inner wall of the nitriding hole. During the nitriding process, a plasma zone is formed between the needle tip and the nitriding hole, and nitrogen ions bombard the needle tip surface at high speed under the action of the electric field, thereby achieving the purpose of local nitriding of the needle tip.

[0011] In a second aspect, the present application provides a method for preparing a martensitic stainless steel suture needle, which adopts the following technical solution: A method for preparing a martensitic stainless steel suture needle comprises the following steps: S1: Processing and shaping the martensitic stainless steel wire, and grinding it to obtain a suture needle having a needle tip, a needle body and a needle tail; S2: placing the suture needle in the above-mentioned ion nitriding tooling for suture needles, inserting the needle tip of the suture needle into the nitriding hole, and inserting the needle tail into the limiting hole, to obtain a tooling for assembling suture needles; After the tooling for assembling suture needles is subjected to surface nitriding treatment in a nitrogen and hydrogen environment, the suture needles are cleaned and dried to obtain surface nitrided martensitic stainless steel suture needles; The voltage of the surface nitriding treatment is 550V, the pressure is 350Pa, the ammonia flow rate is 400sccm, the temperature is 440-480°C, the time is 1-2h, and the volume ratio of nitrogen to hydrogen is 1:3.

[0012] The martensitic stainless steel wire used in this application has good processing performance. By adopting the above technical solution, the martensitic stainless steel suture needle is processed into three parts: the needle tip, the needle body and the needle tail. After the suture needle is fixed with a tooling, the ion nitriding furnace is turned on for ion nitriding. Under the process conditions of the above-mentioned surface nitriding treatment, the needle tip will be bombarded with high-energy nitrogen ions. This bombardment not only realizes the implantation of nitrogen, but also provides uniform heating for the suture needle. Therefore, the ion nitriding used in this application has higher efficiency and better processing effect than traditional gas nitriding or liquid nitriding methods. During the nitriding process, not only can the surface hardness, wear resistance and fatigue resistance of the martensitic stainless steel suture needle be significantly improved, but also the basic shape and size of the suture needle can be kept unchanged, thereby greatly extending its service life.

[0013] At the same time, after the surface of the tooling for assembling the suture needle in the present application is nitrided, the suture needle can be bent as needed after being air-cooled and taken out to achieve the required 1 / 4 arc, 3 / 8 arc and 1 / 2 arc suture needle to meet the needs of different types of surgeries.

[0014] Therefore, the suture needle processing method of the present application not only significantly improves the hardness and sharpness of the suture needle, but also solves the contradiction between the high hardness and high toughness of the suture needle. In addition, the lower hardness and higher toughness of the needle body and the needle tail improve the bendability and needle hole processing of the suture needle, reducing the loss of existing processing equipment and the dependence on high-end processing equipment. Finally, ion nitriding will mix a certain proportion of nitrogen into the suture needle, forming a chromium nitride layer while preventing inter-spindle corrosion, and inhibiting excessive passivation and dissolution of elements such as chromium, making the suture needle more corrosion-resistant.

[0015] Preferably, in S2, the surface nitriding treatment is performed at a temperature of 460° C. for a time of 1 to 2 hours.

[0016] By adopting the above technical solution, the temperature and time of the surface nitriding treatment are further optimized, and the surface hardness of the needle tip of the obtained suture needle is as high as 980-1100HV, which has excellent sharpness and can effectively reduce the puncture force required for suturing.

[0017] Preferably, the S1 comprises the following steps: S11: annealing the martensitic stainless steel wire and then processing and shaping it to obtain a straight needle; S12: heating the straight needle to 1050-1100° C., keeping the temperature for 0.5-1.5 h, and then oil cooling to room temperature to obtain an oil-quenched straight needle; The oil-quenched straight needle is heated to 450-500°C, kept at this temperature for 1-2 hours, and then oil-cooled to room temperature to obtain a tempered straight needle; S13: grinding the tempered straight needle and polishing the surface to obtain a suture needle with a needle tip, a needle body and a needle tail.

[0018] By adopting the above technical solution, the straight needle is first oil quenched at a temperature of 1050-1100°C and then tempered at a temperature of 450-500°C, so that the toughness of the suture needle can be maintained, which is conducive to obtaining a suture needle with both toughness and hardness.

[0019] In a third aspect, the present application provides a martensitic stainless steel suture needle, which adopts the following technical solution: A martensitic stainless steel suture needle is prepared by the martensitic stainless steel suture needle preparation method.

[0020] Preferably, the surface hardness of the martensitic stainless steel suture needle tip is 850-1100 HV.

[0021] By adopting the above technical solution, the suture needle of the present application is divided into three parts: needle tip, needle body and needle tail. After the suture needle is ion nitrided according to the method of the present application, the hardness of the needle tip and the surface of the needle body of the obtained suture needle is as high as HV850-1100, and the hardness of the surface of the needle tail is maintained at HV340-380, and it still has high toughness. Therefore, compared with the suture needle with fixed hardness obtained by processing stainless steel wire, the suture needle processed by this method has the advantages of high hardness, high sharpness, high elasticity and high toughness.

[0022] In summary, this application has the following beneficial effects: 1. Compared with the traditional method of improving the hardness of the suture needle as a whole, the present application divides the martensitic stainless steel suture needle into three parts: the needle tip, the needle body and the needle tail. The suture needle can be locally nitrided by using the ion nitriding tooling for the suture needle. The needle tip of the suture needle is nitrided to improve the hardness of the needle tip while maintaining the elasticity and toughness of the needle body and the needle tail. 2. The processing method of the suture needle in the present application not only solves the problems of the difficulty of subsequent processing and forming of stainless steel wire and the difficulty of needle hole processing, but also solves the contradiction between high hardness, high sharpness and high toughness when making suture needles with a single steel wire. Therefore, after the suture needle is processed by the method of the present application, the needle tip and the needle surface have high hardness and high sharpness, and the needle body of the suture needle has high toughness, which can significantly reduce the brittle fracture tendency of the suture needle. 3. The suture needle of the present application not only has high hardness and sharpness, but also maintains high elasticity and toughness, which can effectively reduce damage to tissues during the suturing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of the ion nitriding furnace in Example 1 of the present application; Figure 2 is a schematic cross-sectional structure diagram of the ion nitriding furnace in Example 1 of the present application; Figure 3 is a schematic cross-sectional structure diagram of the ion nitriding furnace in Example 2 of the present application; Figure 4 It is a schematic diagram of the cross-sectional structure of the ion nitriding tooling for suture needles in Example 2 of the present application.

[0024] Figure numerals: 1. furnace body; 2. base; 3. furnace cover; 4. air inlet pipe; 5. air outlet pipe; 6. air outlet branch pipe; 7. vacuum pump; 8. cathode workbench; 9. DC high voltage power supply; 10. ion nitriding tooling for suture needle; 1001. cathode needle placement plate; 1002. insulating rod; 1003. anode nitriding plate; 1004. nitriding hole; 1005. limiting hole. DETAILED DESCRIPTION

[0025] The present application is further described in detail below with reference to the accompanying drawings and embodiments. Example

[0026] Example 1 An ion nitriding furnace, referring to Figure 1 , comprising a furnace body 1 and a base 2, the furnace body 1 is fixedly arranged on the base 2, and a furnace cover 3 is fixed on the top of the furnace body 1. An air inlet pipe 4 and an air outlet pipe 5 are connected to the side wall of the furnace body 1, and valves are arranged on the air inlet pipe 4 and the air outlet pipe 5, wherein three air outlet branches 6 are arranged in parallel at one end of the air inlet pipe 4 away from the furnace body 1, and nitrogen, hydrogen and ammonia can be transported into the furnace body 1 through the three air outlet branches 6; an air pump 7 is arranged at one end of the air outlet pipe 5 away from the furnace body 1, and the air pump 7 can extract the air in the furnace body 1, and then the gas in the furnace body 1 is ionized under the DC electric field to generate DC glow discharge plasma, so as to perform surface nitriding on the suture needle in the furnace body 1.

[0027] Reference Figure 2 A cathode workbench 8 is fixedly arranged on the base 2, and the cathode workbench 8 is located in the furnace body 1. A DC high-voltage power supply 9 is fixedly arranged on the side of the base 2 away from the cathode workbench 8, and its negative pole is connected to the cathode workbench 8, and its positive pole is connected to the furnace body 1 and grounded for protection, so that a DC electric field can be formed in the furnace body 1. The suture needle is placed on the cathode workbench 8, and the gas in the furnace body 1 is ionized to generate a DC glow discharge plasma and bombard the surface of the suture needle, heating and penetrating the suture needle, thereby forming a hard nitride layer on the surface of the suture needle.

[0028] In order to control the temperature inside the furnace body 1, a temperature sensor is fixedly arranged inside the furnace body 1, and the temperature sensor is electrically connected to the DC high voltage power supply 9 through a current controller. The temperature detector detects the temperature, and when the temperature is high, the current controller can reduce or stop the operation of the DC high voltage power supply 9, thereby increasing the temperature control effect of the device.

[0029] In order to detect the pressure inside the furnace body 1, a pressure sensor is fixedly arranged on the inner wall of the furnace body 1, which can stably detect the pressure inside the furnace body 1 and increase the practicality of the device.

[0030] The implementation principle of an ion nitriding furnace in the embodiment of the present application is as follows: after placing the suture needle on the cathode workbench 8, the furnace body 1 is fixed on the base 2, so that the furnace cover 3, the furnace body 1 and the base 2 form a closed space. Then, the furnace body 1 is first kept in a negative pressure environment by the vacuum pump 7, and then the valve of the air inlet pipe 4 is opened to transport a certain amount of nitrogen, hydrogen and ammonia into the furnace body 1; finally, the DC high-voltage power supply 9 is turned on to perform surface nitriding treatment on the suture needle.

[0031] Example 2 An ion nitriding furnace, referring to Figure 3 , which is different from Example 1 in that it also includes an ion nitriding tool 10 for suture needles. The ion nitriding tool 10 for suture needles includes a cathode needle plate 1001, which is placed on the cathode workbench 8 and electrically connected to the cathode workbench 8. An insulating rod 1002 located on the side of the cathode needle plate 1001 is fixedly arranged on the surface of the cathode workbench 8, and an anode nitriding plate 1003 is penetrated on the insulating rod 1002, which is located on the top of the cathode needle plate 1001 and electrically connected to the furnace body 1.

[0032] Reference Figure 4 A nitriding hole 1004 is provided on the side of the anode nitriding plate 1003 facing the cathode needle plate 1001, and a limiting hole 1005 is provided on the side of the cathode needle plate 1001 facing the anode nitriding plate 1003. The positions of the limiting hole 1005 and the nitriding hole 1004 correspond to each other. The tail of the suture needle is inserted into the limiting hole 1005, and the needle tip is inserted into the nitriding hole 1004 and the needle tip is kept from contacting the inner wall of the nitriding hole 1004. The nitrogen in the furnace body 1 is ionized under the action of the electric field and bombards the needle tip surface at a high speed, thereby achieving the purpose of local nitriding of the needle tip.

[0033] In order to meet the nitriding requirements for suture needles of different diameters, the aperture of the nitriding hole 1004 gradually decreases from the side close to the cathode needle plate 1001 to the side away from the cathode needle plate 1001, and the aperture of the limiting hole 1005 gradually decreases from the side close to the anode nitriding plate 1003 to the side away from the anode nitriding plate 1003.

[0034] The implementation principle of an ion nitriding furnace in the embodiment of the present application is as follows: first insert the suture needle into the limiting hole 1005, keep the needle tail in contact with the inner wall of the limiting hole 1005, and then penetrate the anode nitriding plate 1003 on the insulating rod 1002, so that the needle tip is inserted into the nitriding hole 1004, and keep the needle tip from contacting the inner wall of the nitriding hole 1004. Fix the furnace body 1 on the base 2, so that the furnace cover 3, the furnace body 1 and the base 2 form a closed space. Then, first keep the furnace body 1 in a negative pressure environment through the vacuum pump 7, and then open the valve of the air inlet pipe 4 to transport a certain amount of nitrogen, hydrogen and ammonia into the furnace body 1; finally, turn on the DC high-voltage power supply 9, and a plasma zone can be formed between the needle tip and the nitriding hole 1004, and the nitrogen ions bombard the needle tip surface at high speed under the action of the electric field, so as to achieve the purpose of local nitriding of the needle tip.

[0035] Example 3 A martensitic stainless steel suture needle comprises a needle tail, a needle body and a needle tip.

[0036] The method for preparing the martensitic stainless steel suture needle comprises the following steps: S1: S11: annealing the 2Cr13 martensitic stainless steel wire to obtain a martensitic stainless steel wire with a hardness of HV270, and then uncoiling, straightening, cutting, pinhole processing, and needle tip processing to obtain a straight needle; S12: heating the straight needle to 1050° C., keeping the temperature for 1.5 h, and then oil cooling to room temperature to obtain an oil-quenched straight needle; The oil-quenched straight needle was heated to 450°C, kept at this temperature for 2 hours, and then oil-cooled to room temperature to obtain a tempered straight needle; S13: grinding and fine-finishing the needle tip of the tempered straight needle to make the needle tip sharp and without a virtual tip, and then polishing the surface, cleaning, and drying to obtain a suture needle with a needle tip, a needle body, and a needle tail.

[0037] S2: Place the suture needle in the ion nitriding furnace of Example 2, first insert the needle tail into the limiting hole 1005 of the cathode needle plate 1001, and then penetrate the anode nitriding plate 1003 on the insulating rod 1002 so that the needle tip is inserted into the nitriding hole 1004 of the anode nitriding plate 1003 to complete the placement of the suture needle. Finally, by fixing the furnace body 1 on the base 3, a sealed cavity is formed in the furnace body 1. At this time, turn on the ion nitriding furnace, and perform surface nitriding treatment on the suture needle in a negative pressure environment, nitrogen, hydrogen and ammonia environment, then take out the suture needle for air cooling, cleaning, and drying to obtain a surface nitrided martensitic stainless steel suture needle; The voltage of the surface nitriding treatment is 550 V, the pressure is 350 Pa, the ammonia flow rate is 400 sccm, the temperature is 440° C., the time is 1 h, and the volume ratio of nitrogen to hydrogen is 1:3.

[0038] Embodiments 4 to 11 A martensitic stainless steel suture needle, which is different from Example 3 in that, in the preparation method of the martensitic stainless steel suture needle, the temperature and time of the surface nitriding treatment in step S2 are shown in the following table.

[0039] Example 12 A martensitic stainless steel suture needle, which is different from Example 3 in that, in the method for preparing the martensitic stainless steel suture needle, step S12 is: S12: heating the straight needle to 1100° C., keeping the temperature for 0.5 h, and then oil cooling to room temperature to obtain an oil-quenched straight needle; The oil-quenched straight needle was heated to 500°C, kept at that temperature for 1 hour, and then oil-cooled to room temperature to obtain a tempered straight needle.

[0040] Comparative Example Comparative Examples 1-2 A martensitic stainless steel suture needle, which is different from Example 3 in that, in the preparation method of the martensitic stainless steel suture needle, the temperature and time of the surface nitriding treatment in step S2 are shown in the following table.

[0041] Comparative Example 3 A martensitic stainless steel suture needle is different from Example 3 in that, in the preparation method of the martensitic stainless steel suture needle, step S2 is to place the suture needle in the ion nitriding furnace of Example 1 for surface nitriding treatment.

[0042] Performance Testing The needle tips of martensitic stainless steel suture needles prepared in Examples 3 to 12 of the present application and Comparative Examples 1 to 3 were tested for nitriding depth, surface hardness and toughness. The testing method is shown in the following table: Surface hardness: tested in accordance with YY / T 0043-2016 standard; Toughness: According to the YY / T 0043-2016 standard, the number of times the suture needle breaks is tested and recorded as the number of bending resistance.

[0043] The test results are shown in the following table.

[0044] By analyzing the data in the above table, it can be seen that the needle tips of the martensitic stainless steel suture needles of Examples 3 to 12 have a surface hardness of up to 850 to 1100 HV and a bending resistance of up to 7 to 10 times. This shows that the martensitic stainless steel suture needles prepared by the preparation method of the present application have high hardness and toughness.

[0045] Compared with Example 3, although the bending resistance of Comparative Example 1 is relatively increased by 20%, the surface hardness is relatively reduced by 18.82%; compared with Example 3, although the surface hardness of Comparative Example 2 is relatively increased by 52.94%, the bending resistance is relatively reduced by 40%. This shows that in the preparation method of the martensitic stainless steel suture needle of the present application, the surface nitriding treatment temperature of step S2 is 440-480°C and the time is 1-2h, which can simultaneously improve the hardness and toughness of the suture needle tip.

[0046] Compared with Example 3, although the surface hardness of Comparative Example 3 is relatively increased by 47.06%, the number of bending resistance is relatively reduced by 40%. This shows that in the preparation method of the martensitic stainless steel suture needle of the present application, the suture needle is placed in the ion nitriding tool of Example 2 in step S2, and then the surface is nitrided in the ion nitriding furnace, and the comprehensive performance of the surface hardness of the suture needle tip and the toughness of the needle body is the best.

[0047] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. An ion nitriding tool for suture needles, characterized in that: The invention comprises a cathode needle placement plate (1001) and an anode nitriding plate (1003), wherein the cathode needle placement plate (1001) is connected to the negative electrode of a power supply, and the anode nitriding plate (1003) is located on the top of the cathode needle placement plate (1001) and connected to the positive electrode of the power supply, and a nitriding hole (1004) for accommodating the tip of a suture needle is provided on the surface of the anode nitriding plate (1003), and a limiting position hole (1005) for accommodating the tail of a suture needle is provided on the surface of the cathode needle placement plate (1001).

2. The ion nitriding tool for suture needle according to claim 1, characterized in that: The aperture of the nitriding hole (1004) gradually decreases from the side close to the cathode needle plate (1001) to the side away from the cathode needle plate (1001), and the aperture of the limiting hole (1005) gradually decreases from the side close to the anode nitriding plate (1003) to the side away from the anode nitriding plate (1003).

3. The method for preparing a martensitic stainless steel suture needle according to claim 1, characterized in that: The following steps are involved: S1: Processing and shaping the martensitic stainless steel wire, and grinding it to obtain a suture needle having a needle tip, a needle body and a needle tail; S2: After the needle tip of the suture needle is subjected to surface nitriding treatment, the suture needle is cleaned and dried to obtain a surface nitrided martensitic stainless steel suture needle; The temperature of surface nitriding treatment is 440-480°C and the time is 1-2h.

4. The method for preparing a martensitic stainless steel suture needle according to claim 3, characterized in that: S2 includes the following steps: Placing a suture needle in the ion nitriding tooling for suture needles according to any one of claims 1 to 2, inserting the needle tip of the suture needle into the nitriding hole (1004), and inserting the needle tail into the limiting hole (1005), to obtain a tooling for assembling the suture needle; After the tooling for assembling the suture needle is subjected to surface nitriding treatment in a nitrogen and hydrogen environment, the suture needle is cleaned and dried to obtain a surface nitrided martensitic stainless steel suture needle.

5. The method for preparing a martensitic stainless steel suture needle according to claim 4, characterized in that: In the S2, the voltage of the surface nitriding treatment is 550 V, the pressure is 350 Pa, and the ammonia flow rate is 400 sccm.

6. The method for preparing a martensitic stainless steel suture needle according to claim 5, characterized in that: In the S2, the surface nitriding treatment temperature is 460° C. and the time is 1 to 2 hours.

7. The method for preparing a martensitic stainless steel suture needle according to claim 3, characterized in that: The S1 comprises the following steps: S11: annealing the martensitic stainless steel wire and then processing and shaping it to obtain a straight needle; S12: heating the straight needle to 1050-1100° C., keeping the temperature for 0.5-1.5 h, and then oil cooling to room temperature to obtain an oil-quenched straight needle; The oil-quenched straight needle is heated to 450-500°C, kept at this temperature for 1-2 hours, and then oil-cooled to room temperature to obtain a tempered straight needle; S13: grinding the tempered straight needle and polishing the surface to obtain a suture needle with a needle tip, a needle body and a needle tail.

8. A martensitic stainless steel suture needle, characterized in that: The martensitic stainless steel suture needle is prepared by the method for preparing the martensitic stainless steel suture needle according to any one of claims 1 to 7.

9. The martensitic stainless steel suture needle according to claim 8, characterized in that: The surface hardness of the martensitic stainless steel suture needle tip is 850-1100 HV.

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