CN119243307B - Polishing method of vascular stent - Google Patents
Polishing method of vascular stent Download PDFInfo
- Publication number
- CN119243307B CN119243307B CN202411776039.2A CN202411776039A CN119243307B CN 119243307 B CN119243307 B CN 119243307B CN 202411776039 A CN202411776039 A CN 202411776039A CN 119243307 B CN119243307 B CN 119243307B
- Authority
- CN
- China
- Prior art keywords
- polishing
- vascular stent
- tool
- stent
- main body
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
- C25F3/00—Electrolytic etching or polishing
- C25F3/16—Polishing
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
- A61F2/82—Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
- C25F7/00—Constructional parts, or assemblies thereof, of cells for electrolytic removal of material from objects; Servicing or operating
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
- A61F2240/00—Manufacturing or designing of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
- A61F2240/001—Designing or manufacturing processes
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Organic Chemistry (AREA)
- Metallurgy (AREA)
- Materials Engineering (AREA)
- Electrochemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Transplantation (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Animal Behavior & Ethology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Vascular Medicine (AREA)
- Heart & Thoracic Surgery (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Cardiology (AREA)
- Media Introduction/Drainage Providing Device (AREA)
Abstract
本申请提供了一种血管支架的抛光方法，包括，将待抛光的血管支架装配于抛光工装上，所述抛光工装包括螺旋状设置的工装主体，以及连接于所述工装主体两端的第一连接部和第二连接部，所述血管支架能够套设于所述工装主体外，通过交替重复给抛光工装的两端通电进行电化学抛光，直至血管支架满足抛光要求。本申请采用双侧夹持间歇电解方法，结合抛光工装与血管支架的配合方式，使得电流在血管支架内的分布得到了显著的改进，抛光效果尤为突出，特别适用于细长血管支架。
The present application provides a polishing method for a vascular stent, comprising assembling a vascular stent to be polished on a polishing tool, wherein the polishing tool comprises a tool body arranged in a spiral shape, and a first connecting portion and a second connecting portion connected to both ends of the tool body, wherein the vascular stent can be sleeved outside the tool body, and electrochemical polishing is performed by alternately and repeatedly energizing both ends of the polishing tool until the vascular stent meets the polishing requirements. The present application adopts a double-sided clamping intermittent electrolysis method, combined with the coordination mode of the polishing tool and the vascular stent, so that the distribution of current in the vascular stent is significantly improved, and the polishing effect is particularly prominent, which is particularly suitable for slender vascular stents.
Description
Technical Field
The application relates to the field of medical equipment, in particular to a polishing method of a vascular stent.
Background
The medical metal stent is mainly applied to a narrow tissue cavity or a blood vessel cavity, and helps to reconstruct a blood flow channel of the tissue cavity or the blood vessel cavity and maintain normal physiological functions of a human body. Conventional medical metal stents are typically cut by laser, and slag, burrs and oxide layers are typically present on the surface of the cut metal stent, which must be post-treated, which typically includes grinding, sand blasting, electrochemical polishing, and the like. The electrochemical polishing can reduce the surface roughness of the bracket, improve the biocompatibility of the bracket, improve the overall application performance of the metal bracket and be widely applied to the post-treatment of the metal bracket. The prior art CN207933554U discloses an electrochemical polishing tool for a cardiovascular stent, wherein a tool hole for accommodating the vascular stent is formed in the polishing tool, but by adopting the method, the contact point between the vascular stent and the polishing tool is difficult to ensure, and the polishing effect is not ideal.
Disclosure of Invention
In view of the above, the application provides a polishing method for a vascular stent, which combines an external vascular stent to a polishing main body and a bilateral intermittent electrifying method, so that current is uniformly distributed in the electrolytic process, and the polishing effect is obvious.
The application relates to an electrochemical polishing method of a vascular stent, which comprises the following steps of,
The method comprises the steps that a vascular stent to be polished is assembled on a polishing tool, the polishing tool comprises a tool main body which is spirally arranged, and a first connecting part and a second connecting part which are connected to two ends of the tool main body, and the vascular stent can be sleeved outside the tool main body;
The vascular stent is completely immersed in the polishing solution, a cathode which is connected and conducted with the negative electrode of the power supply is also arranged in the polishing solution, and at the same time, only one of the first connecting part and the second connecting part is conducted with the positive electrode of the power supply;
Step A, the first connecting part is conducted with the positive electrode of the power supply, a current loop is formed by the cathode and the first connecting part, and the vascular stent is subjected to primary electrochemical polishing under the set electrochemical polishing parameters;
B, conducting the second connecting part with the positive electrode of the power supply, forming a current loop by the cathode and the second connecting part, and performing secondary electrochemical polishing on the vascular stent under the set electrochemical polishing parameters;
and (3) alternately repeating the step A and the step B until the polishing times reach a preset value.
Further, the device further comprises a first connecting plate and a second connecting plate which are connected with the positive electrode of the power supply, wherein the first connecting part is connected with the first connecting plate, and the second connecting part is connected with the second connecting plate.
Further, the outer diameter D1 of the tool main body is larger than the inner diameter D2 of the vascular stent.
Further, the outer diameter D1 of the tool main body and the inner diameter D2 of the vascular stent meet the following relation (D1-D2) of more than or equal to 0.5 mm-1 mm.
Further, the inner diameter of the vascular stent can be expanded by 40% -80% by the tool main body.
Further, the polishing solution flows, the polishing solution is a mixed solution of perchloric acid, methanol and n-butanol, and the flow speed of the polishing solution at the vascular stent is 0.1 m/s-0.26 m/s.
Further, the electrochemical polishing parameters comprise polishing voltage U and polishing current I, wherein the polishing voltage U is more than or equal to 10V and less than or equal to 15V in the whole polishing process;
the polishing current I is more than or equal to 1A and less than or equal to 5A.
Further, the electrochemical polishing parameters further comprise single polishing time T, and the single polishing time T is kept unchanged in the whole polishing process and simultaneously satisfies that T is more than or equal to 10s and less than or equal to 30s.
Further, the outer diameter D1 of the tool main body is smaller than or equal to 1.5mm and smaller than or equal to D1 and smaller than or equal to 2.5mm, and the length L of the tool main body is smaller than or equal to 100mm and smaller than or equal to 250mm.
Further, the connecting portion is arranged parallel to the axial direction of the tool main body.
The technical scheme provided by the embodiment of the application can comprise the following beneficial effects:
According to the application, only one end of the polishing tool is electrified at the same time, and the current distribution in the polishing process is obviously improved by alternately replacing the electrified ends of the polishing tool and combining the matching mode of the polishing tool and the vascular stent, so that the polishing effect is particularly outstanding.
Drawings
FIG. 1 is a schematic illustration of an embodiment of a polishing tool of the present application;
FIG. 2 is a schematic illustration of the polishing process of the polishing tool of the present application;
FIG. 3 is a graph of the rib width comparison data of the double-sided clamping and the single clamping in the comparison experiment (1);
fig. 4 is a graph of rib thickness comparison data of double-sided clamping and single clamping in comparison experiment (1).
Reference numerals:
100. The polishing tool comprises a polishing tool body, 12 parts of the tool body, a connecting part, 200 parts of the polishing device, 21 parts of the upper connecting plate, 211 parts of the upper connecting plate, 22 parts of the lower connecting plate, 221 parts of the lower connecting plate, 23 parts of the cathode, 231 parts of the cathode and a cathode connecting end.
Detailed Description
Specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.
A vascular stent is a medical device applied to a vascular lesion for expanding a blood vessel so as to facilitate blood circulation. With the development of the medical field, the variety of vascular stents is increasing, and challenges are also brought to the manufacture of vascular stents. Polishing is an important ring in the manufacture of vascular stents, and electrochemical polishing is widely applied to polishing vascular stents with unique advantages. Currently, the main current methods for electrochemical polishing of vascular stents include single point clamping and single point hanging. The single-point clamping method adopts clamping equipment (such as forceps) to clamp the end part of the vascular stent to be polished to polish the vascular stent. The single-point hanging method adopts a polishing tool with a tool hole inside to load the vascular stent for polishing, and the vascular stent is placed in the tool hole. However, as the variety of vascular stents has evolved, vascular stents have emerged which are relatively long in length and relatively small in inside diameter. Because the vascular stent is composed of metal wires, the inner diameter becomes smaller along with the length increase, and the resistance of the whole vascular stent also increases, so that the existing polishing method is difficult to be applied. For single point clamping, current can only be conducted downwards from the clamping point, but due to the large electrical resistance of the stent, current is difficult to conduct to the end, resulting in uneven polishing. Although the single-point hanging method can increase the contact point so as to facilitate the current to pass, in this way, the contact area is limited, the contact is unstable, and the polishing effect is still not ideal for vascular stents with longer length and smaller inner diameter. At present, no manufacturer can treat the products at home, and only foreign enterprises can process and polish the products instead. The polishing method provided by the application makes up the technical blank well, and greatly reduces the production cost and the production period.
As shown in fig. 1, the present application discloses a polishing tool 100, where the polishing tool 100 includes a tool body 11 disposed in a spiral shape, and connection portions 12 connected to two ends of the tool body 11, which are a first connection portion and a second connection portion, respectively. The vascular stent to be polished is sleeved outside the polishing tool 100. In this embodiment, the outer diameter D1 of the tool body 11 is larger than the inner diameter D2 of the stent to be polished, so that the stent to be polished can be sleeved outside the tool body 11. Vascular stents typically have a limited contracted and a limited expanded state, which correspond to a minimum and maximum inner diameter, respectively. Therefore, unless otherwise specified, the inner diameter D2 of the stent according to the present application is the inner diameter of the stent in a natural state. The inner diameter D2 of the stent is between the minimum inner diameter and the maximum inner diameter, and can be contracted or expanded within a certain range.
In this embodiment, the outer diameter of the spiral ring of the tool main body 11 is kept consistent, and when the vascular stent is externally arranged on the tool main body 11, enough contact points with the vascular stent can be ensured to be provided between the tool main body 11 and the vascular stent, and the contact points are uniformly distributed.
For the single-point hanging mode in the prior art, wires forming the vascular stent can be mutually contacted with each other due to shrinkage, so that polishing solution is difficult to infiltrate the area, and polishing dead angles are caused. The vascular stent is arranged on the outer side of the polishing tool 100, and the vascular stent is expanded, so that the distance between the metal wires is increased, and the contact between the adjacent metal wires is avoided. Meanwhile, in the state, the distance between adjacent metal wires becomes far, and a sufficient escape space for bubbles is provided, so that the bubbles generated by electrolysis can be released in time. If bubbles generated in the polishing process cannot be timely released into the polishing solution, the bubbles can adhere to the surface of the vascular stent, the surface of the vascular stent is prevented from being contacted with the polishing solution, pits can be generated in the bubble area after polishing is finished, and the surface quality of the vascular stent is affected.
To place the stent outside the polishing tool 100, the assembly problem of the stent and the tool is considered, namely, how to fit the stent with smaller size into the polishing tool 100 with larger size. The external stent design is not practical if no suitable means of assembly is available. The applicant utilizes the retractility of the vascular stent, and in the assembling process, firstly expands the vascular stent to be polished, places a stainless steel cylinder with the inner diameter larger than the outer diameter of the tool main body 11 in the vascular stent to be polished, then loads the tool main body 11 into the inner cavity of the stainless steel cylinder, and finally withdraws the stainless steel cylinder to complete the assembling. This fitting is suitable for vascular stents having shape memory and superelastic effects, such as nitinol vascular stents. However, each material has a limit of expansion, and the expansion degree of the stent after assembly is not larger and better in consideration of the expansion requirement in the assembly process, and once the expansion amount of the stent exceeds the maximum expansion amount, the stent cannot be contracted. Therefore, the inner diameter D2 of the stent is preferably set to be 40% -80% larger than the inner diameter D2 of the stent in the natural state, and at this time, the stent can be sufficiently contacted with the polishing liquid, and the assembling requirement can be satisfied.
Preferably, the electrolyte is controlled to transfer mass at a proper rate by controlling the flow rate of the polishing solution based on the structure of the polishing tool 100, so as to improve the polishing effect. The polishing process is a process of electrolyte consumption, and once the electrolyte on the surface of the vascular stent is consumed and cannot be timely replenished, the local electrolyte concentration is changed, so that the vascular stent is unevenly polished. Therefore, the polishing liquid needs to be in a flowing state. When the inner diameter D2 of the vascular stent is 40% -80% larger than that of the vascular stent which is opened by the tool main body 11 in a natural state, the flow speed of the polishing solution at the vascular stent is controlled to be 0.1-0.26 m/s, the mass transfer rate of the electrolyte can better meet the electrolysis requirement under the contact area, and the vascular stent resistance generated by the flow speed is relatively controllable.
In order to ensure that the tool main body 11 and the vascular stent to be polished are firmly contacted in the electrochemical process and simultaneously meet the size requirement during assembly of the tool main body 11 and the vascular stent to be polished, the outer diameter D1 of the tool main body 11 and the inner diameter D2 of the vascular stent to be polished preferably meet the following relation:
(D1-D2)≥0.5mm~1mm
at this time, the vascular stent and the polishing tool 100 can meet the assembly requirement, and the vascular stent can be firmly attached to the tool main body 11, so that the vascular stent is not at risk of falling due to too small size difference.
Compared with the prior art, the tool main body 11 is innovatively arranged on the inner side of the vascular stent, so that the contact area between the vascular stent and the tool main body 11 is greatly increased, and the polishing time and current are effectively saved. The single-point hanging mode of the main stream mode is simple in structure and easy to operate, but in order to enable the vascular stent to enter the tool hole, the outer diameter of the vascular stent is required to be smaller than the inner diameter of the tool hole. Once the outer diameter of the vascular stent is smaller than the inner diameter of the tool hole, a gap exists between the vascular stent and the tool hole, and the vascular stent is difficult to ensure sufficient contact with the polishing tool, so that the vascular stent cannot have enough contact area between the vascular stent and the tool hole, and the polishing effect of the vascular stent is relatively poor. For electrochemical polishing, the contact area and uniformity of the stent and the polishing tool 100 not only affect the polishing quality, but also directly affect the time and current required for the polishing process. If the contact area of the two is large and uniform, the electrolysis process can be uniformly distributed on the surface of the vascular stent, the polishing efficiency is higher, and the required polishing time is shorter. In addition, the current distribution is even, so that local electrolysis is not easy to be excessive, and current waste is caused.
The two ends of the tool main body 11 are further provided with connecting portions 12, the tool main body 11 and the connecting portions 12 are made of the same size, the cross section diameter is preferably 0.2 mm-0.5 mm, and the end values are included. The connection 12 is preferably rectilinear and arranged parallel to the axial direction of the tool body 11 so that the stent can be telescoped into and out of the tool body 11 from the connection 12 when the stent is mounted or dismounted. Especially, when the tool is detached, since the stent is provided on the outer side of the tool body 11, the outer diameter of the tool body 11 can be reduced by stretching the connecting portions 12 at both ends, so that the stent can be smoothly moved out of the tool body 11. In the single-point hanging method, the size of the tool hole is larger than that of the vascular stent, so that the tool hole is convenient to detach, and the connecting part is usually only provided with one end for connecting with the positive electrode of a power supply.
In this embodiment, the connection portion 12 is not only used for connecting the positive electrode of the power supply, but also provides a stress point required for stretching, and therefore, it is required to have a certain length, and it is preferable that the length of the connection portion 12 is 10mm or more and 30mm or less, that is, the material waste is not caused by too long and the effect is not caused by too short.
The tool body 11 and the connecting portion 12 of the polishing tool 100 may be made of the same material or different materials, and preferably made of the same material for processing, such as titanium wire, nickel-titanium alloy wire, stainless steel wire, etc. When the tool body 11 and the connecting portion 12 are made of the same material, the tool body and the connecting portion may be made of one piece of the above materials.
Preferably, the pitch of the tool main body 11 is greater than or equal to 2mm and less than or equal to 5mm. When the pitch is denser, the more contact points between the tool main body 11 and the vascular stent are, the larger the contact area is, and the better the polishing effect is, but once the pitch is too dense, bubbles generated in the polishing process are easily caused to be incapable of being diffused in time, so that the polishing effect is poor. In view of this, according to the assembly structure of the polishing tool 100 and the vascular stent of the present application, the pitch of the tool body 11 is preferably set to 2mm to 5mm, so as to improve the polishing effect of the polishing tool of the present application to the greatest extent. And the stretching tool main body 11 is relatively simple when the vascular stent is detached.
Preferably, the outer diameter D1 of the tool main body 11 is smaller than or equal to 1.5mm and smaller than or equal to D1 and smaller than or equal to 2.5mm, the length L of the tool main body 11 is smaller than or equal to 100mm and smaller than or equal to 250mm, and the size is suitable for vascular stents with the length of 100 mm-250 mm and the inner diameter of 1.2 mm-1.5 mm. The vascular stent is difficult to polish by adopting the prior art, or the polishing effect is poor, so that the polishing requirement is difficult to meet.
The application also discloses a polishing method of the vascular stent, which is combined with the polishing tool 100, and is suitable for polishing the vascular stent. Referring to fig. 2, the polishing apparatus 200 employed in the present application is independently provided with a first connection plate and a second connection plate capable of being connected to the positive electrode of a power source on both upper and lower surfaces, and an upper connection plate 21 and a lower connection plate 22 may be respectively provided according to positions. The upper and lower connection plates 21, 22 are used as connection intermediaries between the polishing tool 100 and the positive electrode of the power supply, and a plurality of polishing tools 100 can be arranged on the connection plates to realize one-time treatment of a plurality of vascular stents. In some embodiments, the connection plate may not be included, and the power supply positive electrode is directly connected to the first connection portion and the second connection portion. A cathode 23 connected to a negative electrode of a power source is provided at a side of the polishing apparatus 200, and the cathode 23 may be designed in a cylindrical shape. When the cathode 23 is provided in a cylindrical shape and the polishing tool 100 is provided at the center of the cylindrical shape, it is possible to ensure that the distances from the polishing tool 100 to the cathode 23 in all directions are uniform, avoiding occurrence of potential differences. In the polishing apparatus 200, a polishing liquid is contained, the polishing liquid is in contact with the cathode, and at the same time in the electrochemical polishing process, the cathode 23 forms a current loop with only one of the upper and lower connection plates 21 and 22.
Before polishing, the vascular stent to be polished is first assembled to the polishing tool 100, the vascular stent to be polished is expanded to the outer side of a stainless steel cylinder as described above, the polishing tool 100 is then inserted into the stainless steel cylinder, and the stainless steel cylinder is finally withdrawn.
After assembly, the polishing tool 100 is placed in a slurry that is flowable to enhance the mass transfer effect. The connection parts 12 at both ends of the polishing tool 100 are connected to the upper connection plate 21 and the lower connection plate 22, respectively, at the first connection part and the second connection part. At this time, although the connection portion 12 is connected to both the upper and lower connection plates 21, 22, the terminals 211, 221 of the upper and lower connection plates 21, 22 are not connected to the power source, and the electrochemical process has not yet been performed. A control switch or other means is required to control the connection of the upper and lower connection plate terminals 211, 221 to the positive electrode of the power supply during the electropolishing process. When polishing is required to be performed through the upper connecting plate 21, the upper connecting plate 21 is conducted with the positive electrode of the power supply, and when polishing is required to be performed through the lower connecting plate 22, the lower connecting plate 22 is conducted with the positive electrode of the power supply. For the polishing method adopted by the application, only one connecting plate is connected and conducted with the positive electrode of the power supply at the same moment of polishing, namely, at the same moment, the upper connecting plate 21 is conducted, the lower connecting plate 22 is disconnected, or the lower connecting plate 22 is conducted, and the upper connecting plate 21 is disconnected.
And then starting the step A, namely conducting the upper connecting plate terminal 211 with the positive electrode of the power supply, conducting the cathode terminal 231 with the negative electrode of the power supply, and performing first electrochemical polishing on the polishing tool 100 according to the set electrochemical polishing parameters. The electrochemical polishing parameters comprise a polishing voltage U, a polishing current I and a single polishing time T. The single polishing time T is the time of single continuous power-on of the upper connecting plate or the lower connecting plate each time. Taking the first electrochemical polishing as an example, the single polishing time T is the energizing time of the upper connecting plate in the first electrochemical polishing.
Preferably, the polishing voltage U satisfies 10 V.ltoreq.U.ltoreq.15V, and the polishing current I satisfies 1 A.ltoreq.I.ltoreq.5A. The electrochemical polishing current and polishing voltage are affected by a limiting diffusion current, wherein the diffusion current refers to a current generated by the diffusion of ions from the polishing liquid onto the electrode for electrode reaction, and in the present application, refers to a current generated by the diffusion of electrolyte into the polishing tool 100. The maximum value of the diffusion current is the limit diffusion current. The magnitude of the diffusion current is influenced by the diffusion speed of the electrolyte, so when the flow speed of the polishing liquid at the vascular stent is 0.1 m/s-0.26 m/s, the polishing current I and the polishing voltage U are respectively set to be 1A-5A and 10V-15V, and are relatively suitable, the vascular stent surface is easy to generate pits once the polishing current I or the polishing voltage U is too low, and excessive polishing is easy to occur when the polishing current I or the polishing voltage U is too high.
Preferably, the single polishing time T satisfies 10 s.ltoreq.T.ltoreq.30s. The single polishing time T is affected by the polishing solution, and in some embodiments, the polishing solution is a mixed solution of perchloric acid, methanol and n-butanol, and since perchloric acid has strong oxidizing property, a proper electrochemical polishing time is required, once the time is too long, excessive corrosion of the vascular stent is easy to occur, and too short time increases the complexity of the polishing process. Meanwhile, the single polishing time T is also influenced by the polishing current I and the polishing voltage U, when the polishing current I meets 1A-5A, and the polishing voltage U meets 10V-15V, the single polishing time T is selected to be 10 s-30 s, and the single polishing time T is greatly suitable for perchloric acid, methanol and n-butanol polishing liquid systems. Meanwhile, in order to maintain the consistency of the removal amounts of the upper and lower ends, it is preferable that the single polishing time is kept unchanged.
And then, the step B is performed, the connection between the upper connecting plate wiring terminal 211 and the positive electrode of the power supply is disconnected, the connection between the lower connecting plate wiring terminal 221 and the positive electrode of the power supply is conducted, the connection mode of the cathode 23 is unchanged, and the polishing tool 100 is subjected to secondary electrochemical polishing according to the set electrochemical polishing parameters. The electrochemical parameter settings of the first electrochemical polishing and the second electrochemical polishing to the subsequent multiple electrochemical polishing may be the same or different. The electrochemical parameters include polishing voltage U, polishing current I and single polishing time T. When the polishing process adopts uniform electrochemical parameters, the operation process can be simplified. When the single polishing time T of each polishing is consistent, the removal amount of the vascular stent is consistent during each polishing, so that the stability of the removal amount of the vascular stent in the polishing process is ensured. Of course, the electrochemical parameter setting can also be adjusted according to the burr condition of the vascular stent.
And then, continuously and alternately replacing the connection conduction of the upper connecting plate terminal 211 and the lower connecting plate terminal 221 with the connection conduction of the power supply anode, wherein the connection mode of the cathode 23 is unchanged in the process, and performing electrochemical polishing under the set electrochemical parameters until the polishing times reach a preset value. That is, steps a and B are repeated alternately until the number of polishing times reaches a preset value. The preset value is preset, and may be determined by pre-experiment or estimated. Before the vascular stents are processed in batches, pre-experiments are generally carried out on the vascular stents in the same batch under the same condition, and the vascular stents can meet the requirements of the size and the surface quality after the measurement is carried out in a plurality of polishing processes, wherein the size and the surface quality of the vascular stents are measured by a microscope, and the surface quality measurement comprises whether burrs, pits and other appearance defects exist or not.
And after polishing, taking the polishing tool 100 and the vascular stent out of the polishing equipment 200, and discharging the polishing tool 100 in the vascular stent to obtain a vascular stent finished product. The stent can be removed by stretching the connecting parts 12 at both ends of the polishing tool 100. Stretching the connecting parts 12 at the two ends causes the tool main body 11 of the middle part to deform under force so as to reduce the diameter, and when the outer diameter of the tool main body is reduced to be smaller than the inner diameter of the vascular stent, the vascular stent can easily withdraw from the tool main body 11.
The polishing tool 100 is designed into a structure with the connecting parts 12 at two ends, and is particularly suitable for the electrochemical polishing method provided by the application, on one hand, the two ends of the connecting parts 12 can be used for connecting two connecting plates at different positions. Compared with a polishing tool with the connecting part arranged on only one side, the polishing tool with the connecting part arranged on both sides is more convenient in the use process, and is more stable in connection with the connecting plate. In some embodiments, an extended hook structure may be disposed on the lower connecting plate 22, and before electrochemical polishing, the connecting portion 12 at the bottom of the polishing tool 100 may be bent appropriately, so that the connecting portion 12 at the bottom and the lower connecting plate 22 are in hanging connection, thereby implementing a conductive function. After polishing, the connection between the upper connection plate 21 and the polishing tool 100 is released, and then the positions of the polishing tool 100 and the lower connection plate 22 are adjusted to release the connection between the polishing tool 100 and the lower connection plate 22.
The bottom of the polishing tool in the prior art is usually a chassis with a supporting base, and if the polishing tool is applied to the polishing method of the application, the spiral chassis at the bottom is limited by the structure which is difficult to clamp, so that the polishing method is difficult to apply to the polishing method of the application. On the other hand, the polishing tool 100 disclosed in the application is particularly convenient in the process of withdrawing the vascular stent because the connecting parts 12 are arranged on both sides of the polishing tool. The connecting part 12 provides a good stress point, so that the tool main body 11 can deform by a sufficient amount simply by stretching the connecting part 12, and the vascular stent can be taken out.
The application abandons the traditional thinking, closely arranges the vascular stent on the outer surface of the polishing tool 100, greatly increases the contact area between the vascular stent and the polishing tool 100, and improves the current distribution condition. On the basis, the application creatively adopts intermittent electrification on two sides to replace the traditional single-side clamping for electrochemical polishing, avoids complex polishing flow, simultaneously improves the uniformity of current in the polishing process compared with single-side continuous electrification, can uniformly remove materials on the surface of the vascular stent in the electrochemical polishing process, avoids the problem of nonuniform local size of the vascular stent, and makes up for the technical blank.
Comparative experiment (1), two groups of vascular stents with an outer diameter of 1.3mm and a length of 100mm were subjected to comparative experiments under the same electrochemical parameters (polishing voltage of 12V, polishing current of 1.5A, single polishing time of 20 s) and the same polishing liquid. The dimension of the vascular stent before polishing is 0.12+/-0.01 mm of the width of the tendon and 0.13+/-0.01 mm of the thickness of the tendon (the width of the tendon is the section width of a metal wire composing the vascular stent, and the thickness of the tendon is the section thickness). The polished dimension of the vascular stent is required to be 0.08+/-0.01 mm in tendon width and 0.09+/-0.01 mm in tendon thickness. In the comparative experiment (1), two groups of test points are uniformly distributed in the axial direction of the vascular stent and have the same positions. The polishing tool clamped on the two sides has the size of 100mm of the length of the tool main body and the outer diameter of 1.6mm, the vascular stent is sleeved on the outer side of the tool main body, and then the polishing tool is polished by adopting a two-end intermittent electrifying method, and the single polishing time is 20s. The single clamping scheme adopts forceps to directly clamp the vascular stent, after one side is electrified, the direction of the vascular stent is turned to carry out the next polishing, and then the processes are alternately repeated until the polishing is finished, wherein the single polishing time of each end is 20s. The dimensional data of the vascular stents after polishing are shown in tables 1 and 2:
table 1 double sided clamping experimental data
Table 2 unilateral clamping experimental data
According to tables 1 and 2 and as shown in fig. 3 and 4, the standard deviation of the tendon width and the tendon thickness of the double-side clamping method provided by the application is obviously lower than that of the traditional single-side clamping method, and the surface polishing of the vascular stent is more uniform.
The foregoing description of the preferred embodiments of the application is not intended to be limiting, but rather to enable any modification, equivalent replacement, improvement or the like to be made within the spirit and principles of the application.
Claims (8)
1. A polishing method of a vascular stent is characterized by comprising the following steps of,
The method comprises the steps that a vascular stent to be polished is assembled on a polishing tool, the polishing tool comprises a tool main body which is spirally arranged, and a first connecting part and a second connecting part which are connected to two ends of the tool main body, the vascular stent can be sleeved outside the tool main body, and the outer diameter D1 of the tool main body is larger than the inner diameter D2 of the vascular stent;
the vascular stent is completely immersed in polishing solution, a cathode connected and conducted with a power supply cathode is further arranged in the polishing solution, the first connecting part is connected with a power supply anode through a first connecting plate, the second connecting part is connected with the power supply anode through a second connecting plate, and at the same time, only one of the first connecting part and the second connecting part is conducted with the power supply anode;
Step A, the first connecting part is conducted with the positive electrode of the power supply, a current loop is formed by the cathode and the first connecting part, and the vascular stent is subjected to primary electrochemical polishing under the set electrochemical polishing parameters;
B, conducting the second connecting part with the positive electrode of the power supply, forming a current loop by the cathode and the second connecting part, and performing secondary electrochemical polishing on the vascular stent under the set electrochemical polishing parameters;
and (3) alternately repeating the step A and the step B until the polishing times reach a preset value.
2. The polishing method according to claim 1, wherein the outer diameter D1 of the tool body and the inner diameter D2 of the stent satisfy the following relationship (D1-D2) > 0.5 mm-1 mm.
3. The polishing method according to claim 1, wherein an inner diameter of the vascular stent can be opened by 40% -80% by the tool main body.
4. The polishing method according to claim 3, wherein the polishing liquid is flowing, the polishing liquid is a mixed solution of perchloric acid, methanol and n-butanol, and the flow rate of the polishing liquid at the vascular stent is 0.1m/s to 0.26m/s.
5. The polishing method as recited in claim 1, wherein the electrochemical polishing parameters include a polishing voltage U, a polishing current I, and the polishing voltage U satisfies 10 v+.u+.15V throughout polishing;
the polishing current I is more than or equal to 1A and less than or equal to 5A.
6. The polishing method as recited in claim 5, wherein the electrochemical polishing parameters further include a single polishing time T, which remains unchanged during the entire polishing process while satisfying 10 s.ltoreq.T.ltoreq.30 s.
7. The polishing method as recited in claim 1, wherein an outer diameter D1 of the tool main body satisfies 1.5 mm.ltoreq.d1.ltoreq.2.5 mm, and a length L of the tool main body satisfies 100 mm.ltoreq.l.ltoreq.250 mm.
8. The polishing method as recited in claim 1, wherein the connecting portion is disposed parallel to the tool body axial direction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202411776039.2A CN119243307B (en) | 2024-12-05 | 2024-12-05 | Polishing method of vascular stent |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202411776039.2A CN119243307B (en) | 2024-12-05 | 2024-12-05 | Polishing method of vascular stent |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN119243307A CN119243307A (en) | 2025-01-03 |
| CN119243307B true CN119243307B (en) | 2025-03-14 |
Family
ID=94032989
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202411776039.2A Active CN119243307B (en) | 2024-12-05 | 2024-12-05 | Polishing method of vascular stent |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN119243307B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN207933554U (en) * | 2018-03-13 | 2018-10-02 | 山东吉威医疗制品有限公司 | A kind of angiocarpy bracket electrochemical polish tooling |
| CN111270240A (en) * | 2020-01-20 | 2020-06-12 | 东南大学泰州生物医药与医疗器械研究院 | Two-step polishing method of magnesium alloy intravascular stent and polishing solution thereof |
| CN111850669A (en) * | 2020-08-17 | 2020-10-30 | 内蒙古工业大学 | Electrochemical polishing device and polishing method for vascular stent |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6679980B1 (en) * | 2001-06-13 | 2004-01-20 | Advanced Cardiovascular Systems, Inc. | Apparatus for electropolishing a stent |
| JP6543076B2 (en) * | 2015-04-23 | 2019-07-10 | 株式会社カネカ | Method of manufacturing tubular body |
| CN108193260A (en) * | 2018-01-26 | 2018-06-22 | 北京大学深圳研究院 | A kind of magnesium alloy blood vessel rack processing of surface polishing and auxiliary body |
| CN217399037U (en) * | 2022-04-11 | 2022-09-09 | 杭州巴泰医疗器械有限公司 | Blood vessel support electrochemical polishing positive pole frock and polishing equipment |
| CN116084003A (en) * | 2023-02-15 | 2023-05-09 | 上海美港沣沅医疗器械有限公司 | Electrochemical polishing device and method for magnesium alloy cylinder |
-
2024
- 2024-12-05 CN CN202411776039.2A patent/CN119243307B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN207933554U (en) * | 2018-03-13 | 2018-10-02 | 山东吉威医疗制品有限公司 | A kind of angiocarpy bracket electrochemical polish tooling |
| CN111270240A (en) * | 2020-01-20 | 2020-06-12 | 东南大学泰州生物医药与医疗器械研究院 | Two-step polishing method of magnesium alloy intravascular stent and polishing solution thereof |
| CN111850669A (en) * | 2020-08-17 | 2020-10-30 | 内蒙古工业大学 | Electrochemical polishing device and polishing method for vascular stent |
Also Published As
| Publication number | Publication date |
|---|---|
| CN119243307A (en) | 2025-01-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9987699B2 (en) | Electrochemical system and method for electropolishing hollow metal bodies | |
| US20110303553A1 (en) | Electrochemical system and method for machining strongly passivating metals | |
| JP6543076B2 (en) | Method of manufacturing tubular body | |
| CN119243307B (en) | Polishing method of vascular stent | |
| EP2382341B1 (en) | Method, apparatus and solution for electropolishing metallic stents | |
| AU2010205768B2 (en) | Method and solution for electropolishing stents made of high strength medical alloys | |
| WO2016171116A1 (en) | Tubular body electropolishing apparatus, anode conductive member for electropolishing apparatus, and method for electropolishing tubular body | |
| CN217399037U (en) | Blood vessel support electrochemical polishing positive pole frock and polishing equipment | |
| CN210287576U (en) | Cathode structure, electrochemical polishing tank and electrochemical polishing equipment | |
| CN112095139B (en) | A cathode structure, electrochemical polishing tank and electrochemical polishing equipment | |
| JP6796685B2 (en) | How to manufacture a tubular body | |
| CN212610979U (en) | An electrochemical polishing device for vascular stent | |
| JP2006514712A (en) | Electro-polishing method for nickel-titanium alloy dental instruments | |
| CN116084002A (en) | A solid medium electrochemical polishing method with controllable and adjustable material removal rate | |
| CN219808029U (en) | Electrochemical polishing device for tubular implant | |
| CN222758367U (en) | Electrochemical polishing holding device | |
| CN216378474U (en) | Novel electrochemical polishing equipment | |
| CN114086236B (en) | Electrolytic polishing method | |
| TWM675584U (en) | Electro-polishing system | |
| CN120776431A (en) | Electrochemical polishing device and polishing method thereof | |
| CN114592227A (en) | Method for treating surface of aluminum-titanium-containing alloy | |
| CN119041000A (en) | Polishing solution, configuration method thereof and polishing method | |
| EP2407582B1 (en) | Method and electrolytic solution for electropolishing stents made of high strength medical alloys | |
| CN118186559A (en) | Electrochemical polishing method for nickel-titanium bracket | |
| CN113481584A (en) | Metal support polishing equipment and process |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |