Scissor blade, self-sharpening scissors and preparation method
By preparing high hardness coatings on the scissor blades and designing the inner concave edges, the efficient shearing and long life of self-sharpening scissors is achieved, solving the problems of scissor wear and shortening service life, and improving the efficiency and cost control of industrial production.
Patent Information
- Application Number
- CN202510322288.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-18
- Publication Date
- 2025-06-03
AI Technical Summary
Scissors are prone to wear and curling problems in long-term shearing operations, resulting in reduced shear performance and shortened service life, especially in industrial production, which increases production costs and reduces production efficiency.
Using first and second coatings with a hardness of at least 5 HRC higher than the scissor blade substrate, the bonding layer, the transition layer and the functional layer are prepared by arc ion plating, and the second edge surface is designed as an inner concave surface to achieve self-sharpening characteristics.
Through the self-sharpening characteristics, the sharpness of the scissors is kept from decreasing, which significantly improves the shear life of the scissors, reduces production costs and improves production efficiency.
Smart Images
Figure CN120080353A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of scissor manufacturing, and in particular, to a scissor blade, a self-sharpening scissor and a preparation method thereof. Background Art
[0002] In modern society, scissors, as a basic and important tool, are widely used in various fields. From cutting clothes and paper-cutting handicrafts in daily life, to fabric cutting and metal sheet processing in industrial production, to surgical operations in the medical field and branch pruning in home gardening, the figure of scissors is everywhere, and its application scenarios are extremely rich, providing great convenience for people's life and production activities.
[0003] However, with the increase in usage frequency and the continuous improvement of usage intensity, scissors face severe challenges during long-term shearing operations. During the frequent opening and closing of the scissor blades and the friction with the material to be cut, problems such as wear and chipping of the blade edges are extremely likely to occur. This not only leads to a decline in the shearing performance of the scissors, making cutting laborious and the cut edges uneven, but also significantly shortens the overall service life of the scissors; in scenarios such as industrial production where high requirements are placed on efficiency and cost control, frequent grinding or replacement of scissors not only increases production costs but also reduces production efficiency, affecting the continuity of the entire production process. Summary of the Invention
[0004] The present invention provides a scissor blade, a self-sharpening scissor and a preparation method thereof, aiming to improve the shearing life of the scissors.
[0005] The scissor blade provided by the present invention includes a scissor blade substrate, and the scissor blade substrate includes a first blade surface and a second blade surface that intersect to form a blade edge.
[0006] The first blade surface is provided with a first coating, and the hardness of the first coating is at least 5 HRC greater than the hardness of the scissor blade substrate.
[0007] The second blade surface is a concave surface extending from the blade edge in a direction away from the blade edge.
[0008] Optionally, the second blade surface is provided with a second coating, and the hardness of the second coating is at least 5 HRC greater than the hardness of the scissor blade substrate.
[0009] Optionally, the second blade surface is provided with a second coating, and the first coating is a hydrophilic coating, and the second coating is a hydrophobic coating.
[0010] Optionally, the first coating and / or the second coating includes a bonding layer, a transition layer and a functional layer sequentially deposited on the scissor blade substrate.
[0011] The functional layer and the transition layer are at least one of transition metal element nitrides, transition metal element carbonitrides, and transition metal element borides, or at least one of ternary or higher multi-element nitrides or carbonitrides composed of transition metal elements and IIIA or IVA group elements;
[0012] The bonding layer is at least one of transition metals and transition metal nitrides, or an alloy composed of transition metals and IIIA or IVA group elements, or a nitride of the alloy;
[0013] The transition metal elements are at least one of the elements in Group IVB, VB, and VIB.
[0014] Optionally, the scissor blade substrate is martensitic stainless steel, the material of the bonding layer is Ti, the material of the transition layer is a nitride of Ti-Al, and the material of the functional layer is a nitride of Ti-Si.
[0015] The method for preparing a scissor blade provided by the present invention is used to prepare the scissor blade described above, and includes the following steps:
[0016] Step 1, heat-treat the scissor blank.
[0017] Step 2, process the heat-treated scissor blank into a scissor blade substrate, the scissor blade substrate includes a first blade surface and a second blade surface that intersect to form a blade edge, and the second blade surface is a concave surface extending from the blade edge away from the blade edge;
[0018] Step 3, prepare a first coating on the first blade surface of the scissor blade substrate, and the hardness of the first coating is at least 5 HRC greater than the hardness of the scissor blade substrate.
[0019] Optionally, it further includes the step of:
[0020] Prepare a second coating on the second blade surface of the scissor blade substrate.
[0021] Optionally, in the step 1, the heat treatment includes the steps of:
[0022] Place the scissor blank at a first preset temperature for heat preservation, and then perform isothermal quenching;
[0023] Temper the quenched scissor blank at a second preset temperature.
[0024] Optionally, the first coating and / or the second coating are prepared by arc ion plating.
[0025] The self-sharpening scissors provided by the present invention include two of the above-mentioned scissor blades or scissor blades prepared by the method for preparing two of the above-mentioned scissor blades, and a connecting part;
[0026] The two scissor blades are rotatably connected through the connecting part with a preset pre-tightening force, and their second cutting surfaces are adjacent; the two scissor blades move towards each other at the cutting edges during the opening and closing process to form a shearing action, and the friction during the shearing action is concentrated at the cutting edges of the scissor blades.
[0027] The present invention has the following beneficial effects:
[0028] For a self-sharpening scissor provided by the present invention, since the hardness of the scissor blade substrate is relatively low and the second cutting surface of the scissor blade is a concave surface, the scissor blade and another scissor blade rub against each other under the action of a lateral thrust, and the rubbing part is concentrated at the cutting edge. The scissor blade substrate on the inner side (second cutting surface) of the cutting edge wears faster than the coating on the outer side (first cutting surface), realizing the self-sharpening characteristic, keeping the sharpness of the scissor from decreasing for a long time, and significantly improving the shearing life of the scissor. Description of the Drawings
[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.
[0030] Figure 1 It is a cross-sectional structure schematic diagram of some embodiments of the scissor blade of the present invention and an enlarged schematic diagram of the cutting edge;
[0031] Figure 2 It is a cross-sectional structure schematic diagram of some embodiments of the scissor blade of the present invention;
[0032] Figure 3 It is a shearing cooperation schematic diagram of two scissor blades of the self-sharpening scissor of the present invention.
[0033] Explanation of the Reference Numerals in the Drawings:
[0034] 1. Scissor blade substrate; 11. First cutting surface; 12. Second cutting surface; 13. Back of the knife; 2. Coating; 21. Bonding layer; 22. Transition layer; 23. Functional layer. Detailed Embodiments
[0035] In order to make the invention purpose, features, and advantages of the present invention more obvious and understandable, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.
[0036] An embodiment of the present invention provides a self-sharpening scissor, which includes two scissor blades and a connecting part.
[0037] Referring to Figure 1 and Figure 2 , wherein, any one of the scissor blades includes a scissor blade base body 1, and the scissor blade base body 1 includes a first cutting edge surface 11 ( Figure 2 point a in Figure 2 line segment ac in Figure 2 curve ab in
[0038] which intersect to form a cutting edge ( Figure 3 ); the first cutting edge surface 11 is provided with a first coating, and the hardness of the first coating is greater than that of the scissor blade base body 1 (the difference is usually greater than 5 HRC). The first coating can cover the entire first cutting edge surface 11, or only cover a certain area of the first cutting edge surface extending from the cutting edge away from the cutting edge; wherein, the second cutting edge surface 12 is a concave surface extending from the cutting edge away from the cutting edge.
[0039] The second cutting edge surface 12 is a concave surface, and the concave surface can be a concave arc surface as shown in Figures 1 - 3 , or a V-shaped concave surface, a polygonal concave surface, a stepped concave surface, a composite curve concave surface, a serrated concave surface, etc. It is required that when the two scissor blades are assembled into a self-sharpening scissor, the friction during shearing is concentrated at the cutting edge of the second cutting edge surface; it should be noted that due to the grinding process of the scissor blade base body and the wear during the scissor shearing process, the second cutting edge surface 12 actually forms a surface contact within a certain range with the material to be sheared or the other scissor blade at the cutting edge, rather than a single point contact. Therefore, in Figure 1 the enlarged view of the cutting edge area of
[0040] the cutting edge of the second cutting edge surface 11 is schematically shown as a plane. Figure 2 The shape of the first cutting edge surface 11 can be a plane or a curved surface with various curvatures, and can be designed according to actual shearing requirements and grinding requirements; the surface (
[0041] section cd in Figure 2 ) where the first cutting edge surface 11 is connected to the back of the blade 13 includes, but is not limited to, a plane, a curved surface, a gradual combination of planes, a combination of curved surfaces, a combination of a plane and a curved surface, and is not specifically limited in this application. Those skilled in the art can design according to the uses, structural strength, aesthetics, etc. of the scissors.In the embodiments of the present invention, the connecting part of the two scissor blades can provide partial pre-tightening force through an internal spring or a spring piece; the rotatable connection methods include but are not limited to rivet connection, bolt connection, pin connection, and elastic member connection, and the connecting parts are respectively the corresponding rivets, bolts, pins, and elastic members; the forms of self-sharpening scissors include but are not limited to straight-edge scissors, curved-edge scissors, U-shaped scissors, wave-edge scissors, ring-handle scissors, eccentric-axis scissors, spring scissors, etc.
[0042] For the self-sharpening scissors provided by the embodiments of the present invention, due to the relatively low hardness of the scissor blade substrate, the scissor blades rub against each other under the action of a lateral thrust, and the coating on the inner side (the second blade surface) of the scissor blade substrate wears faster than the coating on the outer side (the first blade surface), realizing the self-sharpening characteristic, so that the sharpness of the scissors is maintained without decline for a long time, and the shearing life of the scissors is significantly improved.
[0043] Referring to Figure 1 , in some embodiments, a second coating ( Figure 1 In
[0044] In these embodiments, the service life of the self-sharpening scissors can be divided into two stages:
[0045] In the first stage, the surface of the scissor blade edge is covered with a complete or un-worn-through hard coating. Due to the strengthening of the edge by the coating, the shearing life in this stage is significantly improved compared with scissors without a coating.
[0046] In the second stage, the coating on the inner side of the scissor blade edge is worn through to expose the scissor blade substrate. Due to the relatively low hardness of the scissor blade substrate, the scissor blades rub against each other under the action of a lateral thrust, and the wear rate of the second blade surface is greater than that of the first blade surface with a complete coating, realizing the self-sharpening characteristic; after the self-sharpening scissors are used for a period of time, the two scissor blades can still maintain a shearing fit under the action of a certain pre-tightening force (the magnitude of the pre-tightening force can be adjusted according to the coating thickness and shearing flexibility), and the self-sharpening effect can be ensured, so that the sharpness of the scissors is maintained without decline for a long time, and the shearing life of the scissors is further significantly improved.
[0047] In some embodiments, the same coating can be deposited on the first blade surface and the second blade surface of the scissor blade; in addition to having high hardness and wear resistance, the coating can also have characteristics such as friction lubrication, hydrophilicity / hydrophobicity, and corrosion resistance to meet the requirements in different scenario applications.
[0048] In some other embodiments, different coatings may be deposited on the first and second cutting surfaces of the scissor blades to achieve functional differentiation of the coatings on the two cutting surfaces. For example, a hydrophobic coating is selected for the second coating (for example, most common transition metal nitrides, carbonitrides or borides hard coatings have hydrophobicity), and a hydrophilic coating is selected for the first coating (for example, first deposit a common hydrophobic hard coating, and then perform hydrophilic surface modification on this coating. The methods of hydrophilic surface modification include but are not limited to grafting of hydrophilic functional groups, coating of hydrophilic coatings, laser microstructuring, etc.). When the scissors are used to cut materials containing liquid (such as gardening scissors for pruning branches and leaves), the hydrophobic coating on the inner side of the scissors can prevent the juice from sticking, and the hydrophilic coating on the outer side of the scissors can minimize the juice splashing.
[0049] In an embodiment of the present invention, the coating of the scissor blade can be prepared by an arc ion plating process.
[0050] In the prior art, surface strengthening is an effective means to improve the use performance of scissors. However, the cutting edge of the scissors is relatively thin. In particular, the cutting edge angle of some special scissors is even smaller than that of household knives, and the working state of the scissors is that the two cutting edges work together. In addition to the shearing force parallel to the cutting direction, the cutting edge is also affected by the thrust force perpendicular to the cutting direction (in particular, when there is no cutting, the cutting edge is also affected by the pre-tightening thrust of the scissors). Therefore, surface strengthening treatment processes such as nitriding and surface cladding are not applicable to the surface strengthening of scissors because they are prone to cause brittle cracking of the cutting edge. Carburizing treatment is also a common surface strengthening treatment process. However, for scissors treated by carburizing, compared with matrix materials with similar carbon content, it is difficult to achieve a significant improvement in performance, and the corresponding production process becomes complicated, which is not suitable for mass production.
[0051] In the arc ion plating process, ions bombard the surface of the scissor blade with high energy, forming a firm bond between the coating and the scissor blade substrate. This strong bonding force ensures that the coating is not easily detached during the use of the scissors and can stably exert its performance advantages for a long time. Even when the scissors are subjected to large shearing forces and impact forces, the coating can remain intact, providing continuous protection and performance improvement for the scissors; and the arc ion plating technology can achieve uniform coating on the cutting edges of scissors with complex shapes.
[0052] Refer to Figure 1 , in an embodiment of the present invention, both the first coating and the second coating include a bonding layer 21, a transition layer 22 and a functional layer 23 sequentially deposited on the scissor blade substrate 1.
[0053] Among them, the materials of the functional layer and the transition layer can be selected from transition metal element nitrides (such as TiN, CrN), or transition metal element carbonitrides (such as TiCN, CrCN), or transition metal element borides (such as TiB 2 2, HfB2 ), or ternary or higher multi-component nitrides composed of transition metal elements and IIIA or IVA group elements (such as TiAlN, CrAlN, TiSiN, TiAlCN, CrAlCN, TiSiCN, TiAlBN, TiAlSiN, CrAlBN, CrAlSiN, TiCrAlBN, TiCrAlSiN, TiAlSiWN, TiAlSiVN, CrAlSiWN, CrAlBWN, etc.), or ternary or higher multi-component carbonitrides composed of transition metal elements and IIIA or IVA group elements (such as TiAlBCN, TiAlSiCN, CrAlBCN, CrAlSiCN, TiCrAlBCN, TiCrAlSiCN, TiAlSiWCN, TiAlSiVCN, CrAlSiWCN, CrAlBWCN, etc.).
[0054] Among them, the transition metal elements are elements of Group IVB, VB or VIB, such as Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, etc.
[0055] The material of the bonding layer can be selected from transition metals such as Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W or their nitrides (such as TiN, CrN, etc.), or alloys composed of transition metals and IIIA or IVA group elements (such as TiAl, AlCr), or nitrides of alloys (such as TiAlN, CrAlN, etc.).
[0056] In the embodiments of the present invention, as long as the coating satisfies that the hardness of each layer from the scissor blade substrate to the surface gradually increases, the functional layer of the coating will not brittlely break and fall off during the shearing work, and the integrity and sharpness of the scissor edge can be guaranteed.
[0057] Among them, the strength, hardness and friction coefficient of the scissor blade substrate should be matched with the coating, so that during the working process of the scissors, the edge shape and edge angle can be kept as unchanged as possible to maintain an appropriate sharpness.
[0058] The scissor blade proposed in the embodiments of the present invention can be prepared by the following method, including the steps:
[0059] Step 1, heat-treat the scissor blank.
[0060] This step is to perform targeted heat treatment on the scissor blank prepared for plating a specific film system, so that the strength, hardness and friction coefficient of the scissor blank are matched with the subsequent coating, so that the edge shape and edge angle of the scissors can be kept as unchanged as possible during the working process.
[0061] Among them, for the shearing blanks formed by stamping stainless steel, the heat treatment can be carried out through the following steps: Place the shearing blanks at the first preset temperature for heat preservation to make the internal tissue structure of the shearing blanks fully homogenized, ensuring that the properties of each part of the shearing blanks are more uniform; then carry out isothermal quenching to cause phase transformation of the microstructure of the shearing blanks, so that while having higher strength and hardness, it can also have better toughness and fatigue resistance; after that, temper the quenched shearing blanks at the second preset temperature to eliminate the internal stress of the shearing blanks; among them, the first preset temperature is higher than the second preset temperature.
[0062] Step 2: Process the heat-treated shearing blanks into the matrix of the scissor blade. The matrix of the scissor blade includes a first blade surface and a second blade surface that intersect to form an edge. The second blade surface is a concave surface extending from the edge away from the edge.
[0063] In this step, the inner side of the shearing blank can adopt an edge-opening method with a certain arc radius to form the second blade surface. It is necessary to reasonably select the arc radius of the second blade surface so that the friction during shearing of the self-sharpening scissors is concentrated at the edge of the second blade surface, reducing the friction area, thereby making the self-sharpening effect play to the best.
[0064] Step 3: Prepare a first coating on the first blade surface of the matrix of the scissor blade. The hardness of the first coating is at least 5 HRC greater than the hardness of the matrix of the scissor blade.
[0065] In some embodiments, a second coating is prepared on the second blade surface. The hardness of the second coating is at least 5 HRC greater than the hardness of the matrix of the scissor blade.
[0066] In some embodiments, the second coating and the first coating have the same structure and components, and can be obtained by coating the matrix of the scissor blade integrally through the process of arc ion plating.
[0067] In some embodiments, different coatings can be prepared on the second blade surface and the first blade surface of the scissor blade to achieve functional differentiation of the coatings on both sides of the blade surface; for example, a hydrophobic coating is deposited on the second blade surface, and a hydrophilic coating is deposited on the first blade surface or the hydrophobic coating is hydrophilically modified.
[0068] The coating can be prepared by the process of arc ion plating. Before the step of arc ion plating, it is necessary to eliminate the residual stress generated by mechanical processing of the matrix of the scissor blade, and through multiple ultrasonic cleanings to remove the physically adsorbed wax and dirt on the surface of the matrix of the scissor blade, and after acid-base balance, the matrix of the scissor blade is cleaned with pure water and blown dry.
[0069] Deposit a coating on the matrix of the scissor blade by the method of arc ion plating, which specifically includes the following steps:
[0070] Hang the shearing blanks on the special hanger of the ion coating machine, put them into the coating machine, evacuate the cavity to 5×10 -3, heat the workpiece to a certain value between 100 and 500 °C.
[0071] Determine the parameters of the electromagnetic control and permanent magnet control of the arc target, and introduce argon and a certain proportion of hydrogen; control the working pressure at a certain value between 0.1 and 5 Pa or a continuously varying value within a certain range; apply a negative bias voltage of a certain value or a continuously varying value between 100 and 400 V to the workpiece; apply a target current of a certain value between 50 and 200 A to the arc target for chemical cleaning, and perform chemical cleaning with a reduction process on the shearing blank; remove chemical impurities such as chemically adsorbed oxides on the surface of the shearing blank.
[0072] Perform arc ion plating on the shearing blank. According to the corresponding film layer functions, introduce argon or pure nitrogen into the furnace chamber; control the working pressure at a certain value between 0.5 and 5 Pa; adjust the bias voltage applied to the workpiece to a certain value or a continuously varying value between 20 and 300 V; turn on the corresponding arc target, and control the working current of the arc target at a certain value between 50 and 200 A, and deposit a bonding layer, a transition layer, and a functional layer on the shearing blank respectively.
[0073] Among them, the materials of the bonding layer, the transition layer, and the functional layer can be reasonably selected from the range of transition metal and its compound materials provided in the foregoing embodiments according to actual needs, and will not be elaborated here.
[0074] Assemble the scissors blades prepared in the above embodiments to obtain the self-sharpening scissors proposed in the embodiments of the present invention.
[0075] Based on the above embodiments, the present application also proposes the following specific embodiments for preparing scissors blades and self-sharpening scissors. It should be noted that the following specific embodiments are only exemplary in nature and do not limit the protection scope of the present application in any form.
[0076] Embodiment 1
[0077] Preprocessing of the shearing blank: Stamp the spheroidized and annealed martensitic stainless steel plate into a shearing blank, perform isothermal quenching after holding at a certain temperature between 1025 and 1080 °C; then perform tempering at a certain temperature between 180 and 580 °C for more than 4 hours to meet the requirements that the hardness of the scissors blade substrate is at a certain value between 52 and 65 HRC and the strength is greater than 1500 MPa.
[0078] Prepare the scissors blade substrate: After heat treatment, the shearing blank is finely processed through various passes, and the arc radius of the inner side grinding of the shearing blank is precisely controlled to make a qualified conventional shearing blank (scissors blade substrate).
[0079] The blank to be coated is first demagnetized in a demagnetizer to remove the residual magnetism generated by machining, and then placed in an automatic cleaning line for multi-pass ultrasonic cleaning and pure water rinsing to remove the physically adsorbed wax and various dirt on the surface of the blank, and then its acid-base balance is treated; after cleaning, the blank is slowly pulled out of the water, and then dried with compressed air and dried.
[0080] The coating is prepared by arc ion plating:
[0081] Preferably, an ion plating machine with a new type of arc target having electromagnetic control and permanent magnetic control is selected.
[0082] The blank after cleaning and drying is hung on a special coating rack, loaded into the coating machine, and evacuated to 5×10 - 3 Pa, and the temperature in the coating machine furnace is heated to a certain working temperature between 180 and 550 °C.
[0083] First, chemical ion cleaning of the blank is carried out in a reducing atmosphere. A mixed gas of argon and hydrogen is introduced into the furnace, the working pressure in the furnace is controlled at a certain value between 0.5 and 5 Pa, the hydrogen flow rate is controlled to vary in a certain range between 50% and 0% of the total working pressure according to a linear control mode; the bias power supply is turned on, and the cleaning bias is selected in a certain range or a certain value between 20 and 450 V; the special arc target for ion cleaning is turned on, and the arc current of the target is controlled at a certain specific value between 40 and 150 A; ion etching cleaning is carried out for a certain specific time length between 50 and 120 minutes according to a pre-programmed cleaning procedure.
[0084] After completing the chemical ion cleaning, the working gas is changed to pure argon, the working pressure is adjusted to a certain value between 0.5 and 5 Pa, the bias is adjusted to a certain specific value between 20 and 150 V, and the electromagnetic control and permanent magnetic control parameters of the target magnetic field of a column of pure Ti targets are adjusted; the target current is adjusted to a certain specific value between 50 and 150 A, and the pure Ti target is turned on for coating for a certain specific time value between 3 and 30 minutes to complete the deposition of the bonding layer of the blank, and the obtained bonding layer material is Ti.
[0085] The working gas is changed to pure nitrogen, the working pressure is adjusted to a certain specific value between 0.5 and 5 Pa, the bias is adjusted to a certain specific value or a certain range of linear variation between 20 and 250 V; the electromagnetic control and permanent magnetic control parameters of the target magnetic field of a column of Ti-Al targets are adjusted; the target working current is controlled at a certain specific value between 50 and 150 A, and the column of Ti-Al targets is turned on to deposit the transition layer on the blank for a certain specific time length between 30 and 200 minutes, and the obtained transition layer material is a nitride of Ti-Al.
[0086] The working gas is maintained as pure nitrogen, and the working gas pressure is adjusted to a specific value between 0.5 and 5 Pa, and the bias voltage is adjusted to a specific value between 20 and 250 V or a linear change within a range; the electromagnetic control and permanent magnet control parameters of the target magnetic field of a row of Ti-Si targets are adjusted; the target working current is controlled to a specific value between 50 and 150 A, and the row of Ti-Si targets is turned on to perform functional layer coating on the shear for a specific time between 30 and 200 minutes, and the prepared functional layer material is Ti-Si nitride.
[0087] After the coating process is completed, the knife is cooled down and taken out of the oven. The handle is installed, adjusted and tested for sharpness. After passing the test, the durability test is carried out.
[0088] Durability testing is performed on a dedicated testing machine. The principle is to mount the scissors to be tested on the testing machine, and cut the test fabric of standard thickness, standard width and standard material with standard force and standard speed; record the number of times the test fabric is cut as an indicator of the durability of the scissors. At present, the shearing durability of industrial scissors produced by conventional methods is usually between 100,000 and 200,000 times.
[0089] The specific testing process is as follows:
[0090] Install the finished coated scissors on a special shear life tester, reset the counter value to zero, turn on the monitor and the tester power to start shear counting. Stop counting when the test roll begins to break, and the total number of times the test roll is broken is the shear life of the coated scissors.
[0091] Through monitoring and record observation, it can be seen that the integrity of the film layer of the self-sharpening scissors after ion plating is maintained between 400,000 and 600,000 times; after that, the scissor blade matrix appears on the friction surface of the two cutting blades on the inner side of the scissors blade, and the self-sharpening effect begins to appear; continuing the test, the self-sharpening scissors can continue to cut the test cloth after cutting the test roll more than 2 million times, and still maintain good shearing performance.
[0092] It can be seen that the durability of scissors strengthened by arc ion plating can be more than doubled; in addition, with the support of self-sharpening effect, the life of scissors strengthened by coating can be increased by more than 10 times.
[0093] The self-sharpening scissors provided by the embodiment of the present invention can still maintain good shearing performance during long-term use, which is of great significance for reducing production costs, improving production efficiency, and ensuring the continuity of production processes in industrial production.
[0094] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.
Claims
1. A scissors blade, comprising a scissors blade base, wherein the scissors blade base comprises a first edge surface and a second edge surface intersecting to form an edge, wherein: The first blade surface is provided with a first coating, and the hardness of the first coating is at least 5 HRC greater than the hardness of the scissors blade substrate; The second blade surface is an inner concave surface extending from the blade edge toward a direction away from the blade edge.
2. The scissor blade according to claim 1, characterized in that: The second blade surface is provided with a second coating, and the hardness of the second coating is at least 5 HRC greater than the hardness of the scissors blade substrate.
3. The scissor blade according to claim 2, characterized in that: The second blade surface is provided with a second coating, the first coating is a hydrophilic coating, and the second coating is a hydrophobic coating.
4. The scissor blade according to claim 2, characterized in that: The first coating and / or the second coating comprises a bonding layer, a transition layer and a functional layer deposited sequentially on the scissor blade substrate; The functional layer and transition layer are at least one of transition metal element nitrides, transition metal element carbonitrides and transition metal element borides, or at least one of ternary or more multi-element nitrides or carbonitrides composed of transition metal elements and IIIA or IVA group elements; The bonding layer is at least one of a transition metal and a transition metal nitride, or an alloy of a transition metal and a IIIA or IVA group element, or a nitride of the alloy; The transition metal element is at least one of Group IVB, Group VB and Group VIB elements.
5. The scissor blade according to claim 4, characterized in that: The scissor blade substrate is made of martensitic stainless steel, the bonding layer is made of Ti, the transition layer is made of Ti-Al nitride, and the functional layer is made of Ti-Si nitride.
6. A method for preparing a scissors blade, used for preparing the scissors blade according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1, heat treating the cut blank; Step 2, processing the heat-treated shear blank into a scissors blade matrix, wherein the scissors blade matrix includes a first cutting edge and a second cutting edge that intersect to form a cutting edge, wherein the second cutting edge is an inner concave surface extending from the cutting edge to a direction away from the cutting edge; Step 3: prepare a first coating on the first edge surface of the scissors blade substrate, wherein the hardness of the first coating is at least 5 HRC greater than the hardness of the scissors blade substrate.
7. The method for preparing a scissor blade according to claim 6, characterized in that: Also includes the steps: A second coating is prepared on the second edge surface of the scissors blade substrate.
8. The method for preparing a scissor blade according to claim 6, characterized in that: In step 1, the heat treatment comprises the steps of: The sheared blank is placed at a first preset temperature for heat preservation, and then isothermally quenched; The quenched shears are tempered at a second preset temperature.
9. The method for preparing a scissors blade according to claim 7, characterized in that: The first coating layer and / or the second coating layer are prepared by arc ion plating.
10. A self-sharpening scissors, characterized in that: A scissor blade comprising two scissor blades according to any one of claims 1 to 5 or two scissor blades prepared by the scissor blade preparation method according to any one of claims 6 to 9, and a connecting portion; The two scissor blades are rotatably connected with a preset preload force through the connection portion, and their second cutting edges are adjacent. The cutting edges of the two scissor blades move toward each other during the opening and closing process to form a shearing action, and the friction during the shearing action is concentrated on the cutting edges of the scissor blades.