WO2018040301A1

WO2018040301A1 - Co-cr-mo alloy, machining method for scalpel for minimally invasive operation, and scalpel for minimally invasive operation

Info

Publication number: WO2018040301A1
Application number: PCT/CN2016/106411
Authority: WO
Inventors: 李云平; 聂炎; 李军旗
Original assignee: 深圳市圆梦精密技术研究院
Priority date: 2016-08-29
Filing date: 2016-11-18
Publication date: 2018-03-08
Also published as: CN106282671A; CN106282671B

Abstract

A Co-Cr-Mo alloy, composed of the following components in percentage by mass: 22-26% of Cr, 3-6% of Mo, 0.1-0.2% of C, 0.05-0.2% of N, and 0-0.06% of Zr, with the balance being Co and inevitable impurities, wherein the Zr content is not zero. For a scalpel, made of the Co-Cr-Mo alloy, for minimally invasive operation, the hardness of the knife edge is up to 700-900 HV, and the strength is 1200-1300 MPa, so that the elasticity and cutting property of the scalpel are greatly enhanced.

Description

Co-Cr-Mo alloy, processing method of minimally invasive scalpel and minimally invasive scalpel

[0001] The present invention belongs to the technical field of cobalt-based alloys for medical devices, and more particularly to a Co-Cr-Mo alloy, a processing method for a minimally invasive scalpel, and a minimally invasive scalpel.

Background technique

[0002] Traditional minimally invasive scalpels generally use stainless steel and titanium alloys. However, whether it is stainless steel or titanium alloy, during the operation, it is prone to insufficient performance due to hardness, elastic modulus, etc., and the blade is passivated or broken, and it is easy to cause tangles between the blood vessel and the scalpel due to the passivation of the knife edge. .

technical problem

[0003] In view of the shortcomings of the stainless steel and titanium alloy minimally invasive scalpel in terms of hardness and elastic modulus, it is easy to break during the operation, the knife edge passivation and the tangles of the blood vessel and the scalpel due to the passivation of the knife edge. Problem, an embodiment of the present invention provides a Co-Cr-Mo alloy, a processing method of a minimally invasive scalpel, and a minimally invasive scalpel.

Problem solution

Technical solution

[0004] In order to achieve the above object of the invention, the technical solution of the present invention is as follows:

[0005] A Co-Cr-Mo alloy consisting of the following components in mass percentage:

[0006] Cr 22-26%;

[0007] Mo 3-6%;

[0008] C 0.1-0.2%;

[0009] N 0.05-0.2%;

[0010] Zr 0-0.06%;

[0011] The balance is Co and unavoidable impurities, wherein the content of the Zr does not take zero.

[0012] And, a method for processing a minimally invasive scalpel, comprising at least the following steps:

[0013] weighing each component according to the formulation of the Co-Cr-Mo alloy as described above;

[0014] subjecting the weighed components to a smelting process; [0015] performing homogenization treatment on the smelted alloy;

[0016] subjecting the alloy obtained by the homogenization treatment to a thermal processing;

[0017] subjecting the alloy obtained by the hot working treatment to a plate treatment;

[0018] The tool obtained by processing the plate material is subjected to a aging treatment and a nitriding treatment.

[0019] Accordingly, a minimally invasive scalpel prepared by the above method.

[0020] The Co-Cr-Mo alloy provided by the above embodiments of the present invention increases the alloy γ phase by adding carbon to the Co-Cr-Mo, so that the alloy has a biocompatible homologous to form a dispersed carbide. The stability and refinement of the grains; more importantly, the Zr element is added to the alloy, and the Zr element plays a crucial role in the repair of the passivation film on the surface of the alloy, greatly reducing the Cr and Mo elements. On the basis of the content, the corrosion resistance and biocompatibility at the interface are improved, the hot workability of the material is improved, and the elastic modulus, tensile strength and wear resistance of the alloy are finally improved.

Advantageous effects of the invention

Beneficial effect

[0021] The method for processing a minimally invasive scalpel according to an embodiment of the present invention uses a plastic processing method to homogenize the alloy obtained by smelting, so that the components of the alloy are uniform, and the carbides and nitrides are dispersed and distributed. The performance of the alloy is uniform and stable. The hardness of the minimally invasive scalpel is 700~900H V and the strength is up to 1200~1300MPa, which greatly improves the elasticity and cutting performance of the scalpel.

Brief description of the drawing

DRAWINGS

[0022] FIG. 1 is an IQ (Image quality) diagram of EBSD after solution treatment of the Co-24Cr-4Mo-0.15C alloy according to an embodiment of the present invention.

[0023] FIG. 1b is an embodiment of the present invention, after the solution treatment of Co-24Cr-4Mo-0.1C alloy is carried out at 1100 ° C, the relative speed is

1.0s ! , 60%+900°C, IQ map of EBSD after 60% deformation;

[0024] FIG. 1c is an IQ diagram of EBSD after a solution treatment of a Co-24Cr-4Mo-0.15C alloy according to an embodiment of the present invention after 1100 ° C, a relative speed of 1.0 s - 60% + 900 ° C, 60% deformation.

1D is an EBSD of a Co-24Cr-4Mo-0.2C alloy after solution treatment at 1100 ° C, a relative speed of 1.0 s - ', 60% + 900 ° C, 60% deformation after the solution treatment of the embodiment of the present invention. IQ diagram;

[0026] FIG. 1 is a sample of Co-24Cr-4Mo-0.2C-0.15N-0.05Zr alloy after solution treatment, after 1100 °C, relative speed is 1.0s - 60% + 900 °C, IQ map of EBSD after 60% deformation;

2a is a topographical view of a Co-24Cr-4Mo-0.2C-0.15N alloy oxidized in air at 700 ° C according to an embodiment of the present invention;

2b is a topographical view of the Co-24Cr-4Mo-0.2C-0.15N-0.05Zr alloy oxidized in air at 700 ° C according to an embodiment of the present invention;

3a is a cross-sectional view of a Co-24Cr-4Mo-0.2C-0.15N alloy oxidized in air at 700 ° C according to an embodiment of the present invention;

3b is a cross-sectional view of a Co-24Cr-4Mo-0.2C-0.15N-0.05Zr alloy oxidized in air at 700 ° C according to an embodiment of the present invention;

4 is an embodiment of the present invention: a: Co-29Cr-6Mo, b: Co-24Cr-4Mo, c: Co-24Cr-4Mo-0.

15C-0.1N, d: Co-24Cr-4Mo-0.15C-0.lN-0.05Zr alloy sheet sample (thickness lmm, length 50 mm, width 10 mm), 37 ° C in 5% lactic acid solution, 6 Comparison of precipitation ion concentration of alloy constituent elements after immersion for a month (ICP-EOS analysis).

Embodiments of the invention

[0032] In order to make the technical problems, technical solutions, and advantageous effects to be solved by the present invention more clearly, the present invention will be further described in detail below with reference to the embodiments and the accompanying drawings. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0033] Embodiments of the present invention provide a Co-Cr-Mo alloy. The Co-Cr-Mo alloy consists of the following components:

[0034] Cr 22-26%;

[0035] Mo 3-6%;

[0036] C 0.1-0.2%;

[0037] N 0.05-0.2%;

[0038] Zr 0-0.06%;

[0039] The balance is Co and unavoidable impurities, wherein the content of the Zr is not taken as zero.

[0040] In any of the embodiments, Cr can improve the corrosion resistance and biocompatibility of the alloy. When the Cr content is lower than 22%, the presence of Cr does not improve the corrosion resistance of the alloy; after adding the Zr element, since Zr is in the alloy The surface can quickly form a dense oxide film, so that the Cr content is within 26% to ensure the corrosion resistance and biocompatibility of the alloy, and when the Cr content exceeds 26%, it is prone to occur in the subsequent heat treatment process. The δ phase that causes the brittleness of the alloy.

[0041] Mo can improve the grain boundary corrosion performance of the alloy, and solid solution strengthening. In the case of adding Zr, Zr can form a dense oxide film on the surface of the alloy quickly. Compared with the prior art, the corrosion resistance and biocompatibility of the alloy can be ensured under the condition of Mo content of 3 to 6%. .

[0042] The C element having a mass percentage of 0.1 to 0.2% can form a carbide in the alloy to increase the strength of the alloy.

, hardness, stable γ phase, grain refinement.

[0043] The cerium element having a mass percentage of 0.05 to 0.2% can improve the alloy processing property and grain refinement in the alloy.

[0044] The Zr element can repair the passivation film on the surface of the alloy in the alloy, and further increase the metal ion precipitation of the alloy in the body. When the Zr element content is above 0.06%, a brittle s phase is formed in the alloy, which is distributed at the grain boundary, which reduces the toughness of the alloy. Therefore, the Zr content is generally controlled at 0 to 0.06%, and the value of 0 is not taken.

[0045] Preferably, the mass percentage of Zr is 0.03 to 0.06 < 3⁄4. The Zr content is 0.03 0.06% 吋, which can ensure that Cr and Mo can play a corresponding role in the alloy at the above content, and ensure the corrosion resistance and biocompatibility of the alloy.

[0046] The Co-Cr-Mo alloy provided by the above embodiments of the present invention, by adding carbon to Co-Cr-Mo, makes the alloy have a biocompatible homologous to form a dispersed carbide, thereby improving the alloy γ phase. The stability, especially the Zr element repairs the passivation film on the surface of the alloy, compensates for the deficiency of Cr and Mo elements at the interface between the carbide and the alloy matrix, improves the corrosion resistance and biocompatibility at the interface, and also improves the alloy. Modulus of elasticity, tensile strength and wear resistance.

[0047] The present invention further provides a processing method of a minimally invasive scalpel based on the Co-Cr-Mo alloy formulation component provided in the above embodiments.

[0048] In an embodiment, the method for processing the minimally invasive scalpel comprises at least the following steps: weighing the components according to the formulation of the Co-Cr-Mo alloy as described above;

[0049] weighing each component according to the formulation of the Co-Cr-Mo alloy as described above;

[0050] subjecting the weighed components to a smelting process;

[0051] homogenizing the smelted alloy; [0052] subjecting the alloy obtained by the homogenization treatment to a hot working treatment;

[0053] subjecting the alloy obtained by the hot working treatment to a plate treatment;

[0054] The tool obtained by processing the sheet material is subjected to a aging treatment and a nitriding treatment.

In the above processing method, in any of the examples, the melting temperature of the alloy is 1500 ° C and 1500 ° C or more. Preferably, it is 1500 to 1800 ° C, and in this temperature range, melting of all metal components can be achieved. When the temperature exceeds 1800 °C, it will cause waste of energy.

In a preferred embodiment, the alloy smelting process should be carried out under an argon (Ar) atmosphere to avoid the presence of oxygen in the smelting atmosphere which may cause pitting or voiding of the alloy after smelting.

[0057] In a preferred embodiment, after the melting temperature reaches 1450 to 1600 ° C, the temperature is maintained for 30 to 60 minutes to ensure that the components are uniformly melted. At the end of the incubation, the molten alloy is cast into an alloy block. The alloy is then homogenized.

[0058] Preferably, the alloy is homogenized, and the temperature of the homogenization treatment should be 1250~1350 ° C in a vacuum or an inert atmosphere, the heating rate is 10-20 ° C / min, and the temperature is kept for 10-24 h. This is followed by furnace cooling or rapid cooling of the high pressure gas. Wherein, the high pressure gas is any one of high pressure nitrogen or high pressure inert gas

Further preferably, the pressure of the high pressure gas is 0.2 to 0.8 MPa; and the cooling rate of the high pressure nitrogen or high pressure inert gas is 20 to 50 ° C / s. The cooling method has no segregation of the alloy composition.

[0060] Preferably, the homogenized alloy is subjected to a hot working treatment. The thermal processing includes a first stage thermal processing and a second stage thermal processing. The first stage of the hot working treatment has a temperature of 1100 to 1200 ° C, a relative processing rate of 1 to 10 / s, a processing rate of 60 to 70%, and then natural cooling to 800 to 1000 ° C. The segment thermal processing, after the first thermal processing, achieves homogenization of the alloy and prevents the alloy from splitting during subsequent processing. The second stage thermal processing refers to a temperature of 8 00 to 1000 ° C, a relative processing rate of 1 to 10 / s, and a processing rate of 50 to 70%. After the second stage of thermal processing, the grain of the alloy is sharply refined to the micron or submicron level to improve the hardness of the alloy.

[0061] In either embodiment, the sheet is treated as a two-stage hot rolling process.

[0062] Preferably, the first section of the hot rolling treatment has a hot rolling temperature of 1100 to 1200 ° C, a relative processing rate of 1 to 10 / s, a processing rate of 60 to 70%, and then natural cooling to 800 to 1000. The second section of the hot rolling treatment is started at ° C; further preferably, the second section of the hot rolling treatment has a temperature of 800 to 1000 ° C, and the relative processing rate is 1 to 1 0/s, processing rate is 50~70<3⁄4.

[0063] Further, the tool is subjected to a treatment effect. The conditions for treatment are in a vacuum or protective atmosphere at 70

0~900 °C insulation 3~10h. After the treatment, the dispersed carbides and nitrogen compounds are precipitated in the alloy matrix, and the hardness and strength of the alloy are finally improved.

[0064] In a preferred embodiment, the nitriding treatment refers to placing the treated tool in an ammonia atmosphere, at 40

Insulation from 0 to 600 °C for l~5h. After nitriding, the hardness and cutting properties of the alloy (ie, the tool) surface are improved.

[0065] The Co-Cr-Mo alloy provided by the embodiment of the present invention adopts the above method, that is, plastic processing, to prepare a minimally invasive scalpel, and the surface hardness of the knife edge reaches 700-900 HV (Vickers hardness), and the strength is 1200-1300 MPa. The 0.2% yield strength is greater than 900 MPa, which greatly improves the knife edge hardness and cutting performance of the scalpel.

[0066] In order to better illustrate the Co-Cr-Mo alloy and the minimally invasive scalpel provided by the embodiments of the present invention, the following is further explained by various embodiments.

Example

[0067] To save space, the formulation components of the various examples are listed in Table 1.

[0068] Table 1 formula of each embodiment and mechanical properties of the alloy under different hot working conditions

[]

C , 1100 ° C

10 Co-24Cr-4Mo-0.15 964 392 1260 23.2 Thermal processing 60%

C-0.05N, 1100°C

11 Co-24Cr-4Mo-0.15 985 395 1275 25.2 Thermal processing 60%

C-0.1N, 1100 ° C

12 Co-24Cr-4Mo-0.15 990 398 1281 25.5 Thermal processing 60%

C-0.15N , 1100 ° C

13 Co-24Cr-4Mo-0.15 1005 403 1310 25.2 Thermal processing 60%

C-0.2N, 1100°C

14 Co-24Cr-4Mo-0.15 991 394 1282 25.6 Thermal processing 60%

C-0.15N-0.01Zr , 1100 ° C

15 Co-24Cr-4Mo-0.15 992 395 1283 25.5 Thermal processing 60%

C-0.15N-0.05Zr , 1100 ° C

16 Co-24Cr-4Mo-0.15 994 397 1285 21.0 Thermal processing 60%

C-0.15N-0.1Zr , 1100 ° C

[0069] Table 2 alloy after hot processing of Table 1 and processed into a scalpel and nitrided surface hardness of the scalpel

[]

[Table 2]

[0070] As can be seen from Tables 1 and 2, the mechanical properties of the alloy are significantly enhanced and the hardness is increased with the increase of carbon content and nitrogen content.

[0071] Different embodiments of the alloy are prepared into a scalpel, and the hardness of the knife edge after nitriding can be further improved on the basis of the hardness of the alloy in Table 1, and the cutting performance of the scalpel is greatly improved.

[0072] As can be seen from FIG. 1 to FIG. 11, as the carbon and nitrogen contents increase, the growth of crystal grains is restricted, which is advantageous for forming finer crystal grains, thereby improving the strength of the alloy.

[0073] It can be seen from FIGS. 2a and 2b that the surface contains a trace amount of Zr element, which is favorable for forming a denser oxide film on the surface. [0074] It can be seen from 3a and 3b that a small amount of Zr element on the surface is favorable for forming a denser oxide film on the surface of the alloy, suppressing precipitation of the alloying element through the oxide film in the living environment, and improving the biocompatibility of the alloy.

[0075] As can be seen from FIG. 4, a: Co-29Cr-6Mo, b: Co-24Cr-4Mo, c: Co-24Cr-4Mo-0.15C-0.

1N, d: Co-24Cr-4Mo-0.15C-0.lN-0.05Zr four alloys were placed in a 5% lactic acid solution at 37 ° C for 6 months and analyzed by ICP-EOS. The alloy with Zr element added has a large decrease in the concentration of Co, Cr and Mo ions. That is to say, the Zr element repairs the passivation film on the surface of the alloy, improves the corrosion resistance of the alloy, and avoids the formation of the alloy. The precipitation of metal ions in the living body further improves the safety performance of the minimally invasive scalpel.

The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, and improvements made within the spirit and scope of the present invention should be included in the present invention. Within the scope of protection of the invention.

Claims

Claim

[Claim 1] A Co-Cr-Mo alloy characterized by: consisting of the following components

Cr 22-26%;

Mo 3-6%;

C 0.1-0.2%;

N 0.05-0.2%;

Zr 0-0.06%;

The balance is Co and unavoidable impurities, wherein the content of Zr is not taken as zero.

[Claim 2] The Co-Cr-Mo alloy according to claim 1, wherein: the Zr content is 0.0

3~0.06<3⁄4.

[Claim 3] A method for processing a minimally invasive scalpel, comprising at least the following steps:

The composition of the Co-Cr-Mo alloy according to any one of claims 1 to 2, wherein each component is weighed; and the weighed components are subjected to smelting treatment;

Homogenizing the smelted alloy;

The alloy obtained by the homogenization treatment is subjected to a hot working treatment;

The alloy obtained by the hot working treatment is subjected to sheet metal treatment;

The tool obtained by processing the plate material is subjected to aging and nitriding treatment.

[Claim 4] The method for processing a minimally invasive scalpel according to claim 3, wherein: the thermal processing process comprises a first stage thermal processing and a second thermal processing; The temperature of the hot working treatment is 1100~1200°C, the relative processing rate is 0.1~10/s, the processing rate is 60~70%, and then the natural cooling is performed to 800~1000°C, and the second stage thermal processing is performed; The processing temperature is 50~70<3⁄4. The processing speed is 50~70<3⁄4. The processing temperature is 0. l-10/s, and the processing rate is 50~70<3⁄4.

[Claim 5] The method for processing a minimally invasive scalpel according to claim 3, wherein the smelting is performed in an argon atmosphere at a temperature of 1450 to 1600 ° C and a holding time of 30 to 60 minutes.

[Claim 6] The method for processing a minimally invasive scalpel according to claim 3, wherein: the homogenization temperature is 1250 to 1350 ° C, the heating rate is 10 to 20 ° C / min, and the vacuum is Or inert gas In the atmosphere, the insulation time is 10~24h.

[Claim 7] The method for processing a minimally invasive scalpel according to claim 3, wherein: the homogenization treatment further comprises rapid cooling of the furnace or high pressure gas; and the rapid cooling rate of the high pressure gas is 10~ 50 ° C / s, the gas pressure is 0.2 ~ 0.8MPa; the high pressure gas is either nitrogen or an inert gas.

[Claim 8] The method for processing a minimally invasive scalpel according to claim 3, wherein: the sheet material is processed into two sections of hot rolling; wherein the hot rolling temperature of the first section of hot rolling is 1100 to 1200 °C, the relative processing rate is l~10/s, the processing rate is 60~70%, and then naturally cooled to 800~1000°C, the second hot rolling process is performed; the temperature of the second hot rolling process is 800~10 00 °C, the relative processing rate is l~10/s, and the processing rate is 50~70<3⁄4.

[Claim 9] The method for processing a minimally invasive scalpel according to claim 3, wherein: the aging treatment is performed at 700 to 900 ° C for 3 to 10 hours under vacuum or a protective atmosphere; The treatment is carried out for 1 to 5 hours in an environment of 400 to 700 ° C under an ammonia atmosphere.

[Claim 10] A minimally invasive scalpel according to any of claims 3-9.