CN114606465A

CN114606465A - Method for producing cutting wire and cutting wire

Info

Publication number: CN114606465A
Application number: CN202210102939.3A
Authority: CN
Inventors: 徐龙; 陈冲; 蔡辉硕; 陈晓
Original assignee: Shenzhen Fulian Intelligent Manufacturing Industry Innovation Center Co ltd
Current assignee: Shenzhen Fulian Intelligent Manufacturing Industry Innovation Center Co ltd
Priority date: 2022-01-27
Filing date: 2022-01-27
Publication date: 2022-06-10
Anticipated expiration: 2042-01-27
Also published as: CN114606465B

Abstract

The application provides a preparation method of a cutting line and the cutting line, wherein the preparation method of the cutting line comprises the following steps: providing a carbon fiber matrix; depositing a silicon-titanium substrate layer on the carbon fiber substrate by adopting physical vapor deposition, wherein the mass fraction of silicon in the silicon-titanium substrate layer is 5-50%; and depositing a diamond layer on the silicon-titanium substrate layer by adopting chemical vapor deposition to obtain the cutting wire, wherein each square millimeter of the diamond layer contains 200-2000 diamond particles. In the application, the content of silicon atoms is controlled through physical vapor deposition, and then the content of diamond particles deposited on a silicon-titanium substrate layer through chemical vapor deposition is controlled. The cutting line has excellent cutting efficiency when the diamond layer contains 200-2000 diamond particles per square millimeter.

Description

Method for producing cutting wire and cutting wire

Technical Field

The application relates to cutting of superhard materials, in particular to a cutting line and a preparation method thereof.

Background

In the 90 s of the 20 th century, in order to solve the processing problem of large-size silicon wafers, a wire saw processing technology is adopted to cut silicon rods into slices. Early wire saw processing techniques, which employed bare wire and free abrasive, were successfully used for silicon and silicon carbide processing, in which a third abrasive was introduced between the wire and the workpiece to effect cutting. On the basis of the above wire sawing technique, in order to further shorten the machining time and to correspond to the application of the wire sawing technique to other hard substances and difficult-to-machine ceramics, diamond abrasives are fixed to a metal wire in a certain manner, resulting in a fixed diamond cutting wire.

Currently, most fixed diamond cutting wires employ electroplating to deposit a layer of metal (typically nickel and nickel-cobalt alloys) on the wire and to consolidate the diamond abrasive within the metal. Wherein, the smaller the wire diameter of the diamond cutting wire, the less the loss of the cut workpiece. But the cutting line can be thinned gradually after being used for many times, the thinning can be drawn layer by layer, along with the increase of the deformation of the cutting line, the crystal defects of the cutting line are more, the poor shaping of the cutting line is caused, the breaking force is smaller, the cutting line is easy to break in the cutting process, and therefore the cutting efficiency and the cutting quality are influenced. In addition, during the electroplating process, sewage is also generated, such as spent electroplating solution, which causes water pollution.

Disclosure of Invention

In view of the above, the present application provides a method for manufacturing a cutting wire and a cutting wire, so as to solve the above problems.

The application provides a preparation method of a cutting line, which comprises the following steps: providing a carbon fiber matrix; depositing a silicon-titanium substrate layer on the carbon fiber substrate by adopting physical vapor deposition, wherein the mass fraction of silicon in the silicon-titanium substrate layer is 5-50%; and depositing a diamond layer on the silicon-titanium substrate layer by adopting chemical vapor deposition to obtain the cutting wire, wherein each square millimeter of the diamond layer contains 200-2000 diamond particles.

In some embodiments, the method of preparing the cutting wire further comprises, prior to depositing the diamond layer:

and placing the carbon fiber substrate with the silicon-titanium substrate layer deposited on the surface in vacuum, and carrying out heat treatment under the inert gas condition, wherein the heat treatment temperature is 600-1200 ℃, and the heat treatment time is 1-3 h.

In some embodiments, prior to depositing the silicon-titanium substrate layer, the method of preparing the cutting wire further comprises:

and (2) placing the carbon fiber substrate in vacuum, and carrying out pretreatment under the condition of inert gas, wherein the pretreatment temperature is 600-1200 ℃, and the pretreatment time is 1-3 h.

In some embodiments, the chemical vapor deposition uses methane and hydrogen as a gas source, the volume ratio of methane is 1% -10%, the volume ratio of hydrogen is 90% -99%, the temperature of the chemical vapor deposition is 600 ℃ -1000 ℃, the pressure is 100-300torr, and the deposition time is 4-10 h.

In some embodiments, the physical vapor deposition uses silicon-titanium alloy as a target source, the deposition time is 5-10h, and the deposition temperature is 450-.

The application also provides a cutting line, which comprises a carbon fiber substrate, a silicon-titanium substrate layer arranged on the carbon fiber substrate and a diamond layer arranged on the silicon-titanium substrate layer, wherein at least part of silicon atoms or titanium atoms in the silicon-titanium substrate layer are bonded to the carbon fiber substrate through chemical bonds, the silicon in the silicon-titanium substrate layer accounts for 5-50% by mass, and each square millimeter in the diamond layer contains 200-2000 diamond particles.

In some embodiments, the carbon fiber matrix comprises a plurality of individual carbon fibers woven into a bundle.

In some embodiments, when the carbon fiber matrix is the single carbon fiber, the diameter of the cutting line is 10 to 20 μm.

In some embodiments, the silicon-titanium substrate layer has a thickness of 1-10 μm.

In some embodiments, the diamond particles in the diamond layer have a size of 5 μm to 30 μm.

In some embodiments, the diameter of the cutting line made of a single carbon fiber matrix is 10 to 20 μm.

In this application, the carbon fiber has characteristics such as excellent tensile, antitorque, fatigue strength, elastic modulus and pliability, chooses for use the carbon fiber as the base member, can improve the plastic deformation ability of line of cut, prolongs the life of line of cut. The silicon-titanium substrate layer is formed on the carbon fiber substrate by adopting physical vapor deposition to improve the bonding force between the substrate and the silicon-titanium substrate layer, and the diamond particles are further formed on the silicon-titanium substrate layer by adopting chemical vapor deposition, and are connected to silicon atoms in the silicon-titanium substrate layer through chemical bonds, so that the bonding force between the silicon-titanium substrate layer and the diamond is improved, and the cutting efficiency and the cutting quality of the cutting line are improved. Meanwhile, the content of silicon atoms is controlled by adopting physical vapor deposition, and the silicon atoms deposited on the carbon fiber substrate are uniformly distributed, so that the content and the distribution condition of diamond particles are controlled. And the content of silicon atoms is controlled so that 200-2000 diamond particles are contained in each square millimeter of the diamond layer, the cutting line has excellent cutting efficiency. Meanwhile, the preparation method provided by the application is environment-friendly and causes little pollution to the environment.

Drawings

FIG. 1 is a schematic representation of a carbon fiber matrix of the first embodiment with a silicon-titanium substrate layer deposited thereon.

FIG. 2 is a schematic view of a silicon-titanium substrate layer with a diamond layer deposited thereon according to the embodiment of FIG. 1.

FIG. 3 is a SEM image of the scribe lines prepared in the second example.

Description of the main elements

Carbon fiber substrate 10

Silicon-titanium substrate layer 20

Intermediate layer 21

Titanium atom 221

Silicon atom 222

Diamond layer 30

Diamond particles 31

Detailed Description

The following describes embodiments of the present invention in detail. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Carbon fiber is a special fiber composed of carbon elements. The carbon fiber has the characteristics of high temperature resistance, friction resistance, electric conduction, heat conduction, corrosion resistance and the like. Because the graphite microcrystalline structure of the fiber is preferentially oriented along the fiber axis, the fiber has high strength and modulus along the fiber axis. The carbon fiber is mainly used as a reinforcing material to be compounded with resin, metal, ceramic, carbon and the like to manufacture an advanced composite material. If carbon fiber is used as a matrix, the wire diameter of the cutting wire can be obviously reduced, and the high strength and modulus of the carbon fiber can greatly reduce the wire breakage rate in the cutting process. Wherein, modulus refers to the ratio of stress to strain of the material under stress. The carbon fiber has the characteristics of excellent tensile strength, torsion resistance, fatigue strength, elastic modulus, flexibility and the like, and the plastic deformation capacity of the cutting line can be improved by selecting the carbon fiber as a matrix.

The application provides a preparation method of a cutting line, which comprises the following steps:

s1, providing a carbon fiber matrix 10.

In some embodiments, the carbon fiber matrix 10 includes a plurality of individual carbon fibers that are woven to form the carbon fiber matrix 10 in a bundle. The carbon fiber matrix 10 may specifically comprise 1, 25 or 30 carbon fibers, wherein the diameter of the individual carbon fibers is 5-7 μm.

And S2, preprocessing the carbon fiber matrix 10.

Specifically, the carbon fiber substrate 10 in the step S1 is placed in a vacuum, and heat treatment is performed under the inert gas condition, wherein the heat treatment temperature is 600-1200 ℃, and the heat treatment time is 1-3 h. At such high temperature and time, internal defects (e.g., local overstress) of each carbon fiber in the carbon fiber matrix 10 are substantially eliminated, thereby enhancing the tensile modulus of each carbon fiber and increasing the service life of the cutting wire.

And S3, depositing a silicon-titanium substrate layer 20 on the carbon fiber matrix 10 by adopting a physical vapor deposition method.

When the physical vapor deposition method is adopted, the silicon-titanium alloy is used as a target source, the temperature is 450-750 ℃, and deposition is carried out for 5-10h under the inert gas condition, so that silicon atoms 222 and titanium atoms 221 are deposited on the surface of the carbon fiber substrate 10. Wherein the content of silicon in the silicon-titanium substrate layer 20 can be adjusted according to the number of diamond particles 31 required in the cutting wire. Wherein the mass fraction of silicon in the silicon-titanium substrate layer 20 is 5% -50%.

In some embodiments, the thickness of the silicon-titanium substrate layer 20 is 1-10 μm, which not only improves the bonding force between the diamond layer 30 deposited on the silicon-titanium substrate layer 20 and the carbon fiber matrix 10, but also ensures the plastic deformability of the cutting wire. If the thickness of the silicon-titanium substrate layer 20 is larger than 10 μm, the whole cutting line has the performance of the silicon-titanium alloy in the silicon-titanium substrate layer 20 along with the increase of the thickness of the silicon-titanium alloy in the silicon-titanium substrate layer 20, so that the brittleness of the cutting line is increased, and the service life of the cutting line is shortened. If the thickness of the silicon-titanium substrate layer 20 is less than 1 μm, not only the effect of improving the bonding force between the carbon fiber substrate 10 and the diamond layer 30 is not obvious, but also the carbon fiber substrate 10 is etched by hydrogen in the process of depositing and growing diamond by the subsequent cutting line because the carbon fiber substrate 10 is lack of the protection of the silicon-titanium substrate layer 20.

And S4, carrying out heat treatment on the carbon fiber matrix 10 with the silicon-titanium substrate layer 20 deposited on the surface in the step S3.

Referring to fig. 1, a silicon-titanium substrate layer 20 is deposited on a carbon fiber matrix 10, and at this time, the silicon-titanium substrate layer 20 is deposited on the carbon fiber matrix 10 in the form of a silicon-titanium alloy in which silicon atoms 222 and titanium atoms 221 are distributed on the carbon fiber matrix 10.

And (3) putting the carbon fiber substrate 10 deposited with the silicon-titanium substrate layer 20 into an oven with the temperature of 600-1200 ℃, and carrying out heat treatment under vacuum and inert gas for 1-3 h. Under the high-temperature condition, the carbon fiber substrate 10 reacts with part of the silicon atoms 222 and the titanium atoms 221 in the silicon-titanium substrate layer 20 to generate the intermediate layer 21 containing silicon carbide and titanium carbide, so that the carbon fiber substrate 10 and the silicon-titanium substrate layer 20 are combined in a chemical bond mode, the bonding force between the two is improved, and the service life of the cutting line is prolonged.

S5, depositing a diamond layer 30 on the silicon-titanium substrate layer 20 by adopting chemical vapor deposition to obtain a cutting line, wherein each square millimeter of the diamond layer 30 contains 200-2000 diamond particles 31.

In some embodiments, the diamond layer 30 is deposited on the silicon-titanium substrate layer 20 by using methane and hydrogen as gas sources by a chemical vapor deposition method, wherein the volume ratio of methane is 1-10%, the volume ratio of hydrogen is 90-99%, the temperature is 600-1200 ℃, the pressure is 100-300torr, and the deposition time is 4-10 h. Under the above parameters, the gas source excites plasma in the reaction chamber and deposits diamond particles 31 on the silicon-titanium substrate layer 20, as shown in fig. 2. Wherein the diamond particles 31 are mainly deposited and grown on the silicon atoms 222 of the silicon-titanium alloy in the silicon-titanium substrate layer 20. Under the conditions of the temperature and the pressure, the methane and the hydrogen form a hydrogen-rich environment and generate active carbon-containing groups, carbon atoms in the active carbon-containing groups diffuse inwards on the surface of the silicon-titanium substrate layer 20 first, the carbon atoms cannot stay and nucleate on the silicon-titanium substrate layer 20 until the nucleation rate of the carbon atoms on the surface of the silicon-titanium substrate layer 20 is greater than the inward diffusion rate, and then diamond starts to grow on the surface of the silicon-titanium substrate layer 20 and is deposited and grown to form diamond particles within 4-10h of the deposition time. And because the atomic arrangement structure of silicon is similar to that of diamond, carbon atoms can rapidly nucleate and grow on the silicon surface. Overall, it appears that diamond preferentially nucleates on silicon surfaces of silicon titanium alloys. Therefore, the volume ratio, temperature, pressure, and deposition time of the gas source described above are important conditions for growing and producing the diamond particles 31.

In some embodiments, 200-2000 diamond particles 31 per square millimeter are contained in the diamond layer 30. When the content of the diamond particles 31 per square millimeter in the diamond layer 30 is within the above range, the cutting efficiency of the resulting cutting wire is high, and the production demand can be satisfied. If the time required for cutting the processed product is longer when the number of diamond particles 31 per square millimeter is small in the diamond layer 30, the cutting efficiency of the cutting line is lowered. If the number of diamond particles 31 per square millimeter in the diamond layer 30 is too large, not only the mass fraction of silicon in the physical vapor deposition needs to be increased, but also the deposition time of the physical vapor deposition and the chemical vapor deposition needs to be increased at the same time, so as to increase the production cost, and at the same time, because the number of diamond particles 31 per unit area on the surface of the cutting line is too large, the diamond layer 30 is formed into a film and tends to be planarized, so that the cutting line loses the cutting ability, and the cutting efficiency of the cutting line is reduced.

In the application, by means of physical vapor deposition and chemical vapor deposition, diamond particles 31 are uniformly distributed on the silicon-titanium substrate layer 20, and the carbon fiber matrix 10 on which the silicon-titanium substrate layer 20 is deposited is subjected to heat treatment, so that the silicon-titanium substrate layer 20 and the carbon fiber matrix 10 are further combined in a chemical bond connection mode, and the plasticity of the cutting line is improved. Compared with the existing electroplating mode, the method provided by the application is more environment-friendly.

Referring to fig. 2, the present application further provides a cutting line, the cutting line includes a carbon fiber substrate 10, a silicon-titanium substrate layer 20 disposed on the carbon fiber substrate 10, and a diamond layer 30 disposed on the silicon-titanium substrate layer 20, at least a portion of silicon atoms 222 or titanium atoms 221 in the silicon-titanium substrate layer 20 is bonded to the carbon fiber substrate 10 through a chemical bond, the silicon accounts for 5-50% of the mass fraction in the silicon-titanium substrate layer 20, and each square millimeter in the diamond layer 30 contains 200-2000 diamond particles 31.

In the cutting line, the silicon atoms 222 or the titanium atoms 221 in the silicon-titanium substrate layer 20 are bonded to the carbon fiber matrix 10 through chemical bonds, so that the bonding force between the silicon-titanium substrate layer 20 and the carbon fiber matrix 10 is improved. Due to the existence of the silicon-titanium substrate layer 20, the carbon fiber matrix 10 cannot be damaged by the cutting line in the cutting process, so that the wire breakage rate of the cutting line is reduced; meanwhile, the diamond particles 31 are deposited and grown on the silicon-titanium substrate layer 20, so that the cutting efficiency of the cutting line is improved. Wherein, when the silicon accounts for 5-50% of the mass fraction of the silicon-titanium substrate layer 20, the diamond layer 30 can contain 200-2000 particles per square millimeter, and the cutting efficiency and the cutting quality of the cutting line for cutting the workpiece can be ensured.

In some embodiments, the carbon fiber matrix 10 includes a plurality of individual carbon fibers that are woven into a bundle. In actual production, the number of the carbon fibers can be correspondingly adjusted according to production requirements.

In some embodiments, when the carbon fiber matrix 10 is the single carbon fiber, the diameter of the cutting line is 10-20 μm. The cutting line made of a single carbon fiber matrix 10 also has good cutting efficiency. Compared with the existing cutting line with the minimum diameter of 40 mu m, the cutting line provided by the application can save the material of a processed workpiece.

In some embodiments, the diamond particles 31 in the diamond layer 30 have a particle size of 5 to 30 μm. The diamond particles 31 have a particle size within the above range, ensuring cutting efficiency and cutting quality of the cutting wire. When the particle diameter of the diamond particles 31 is less than 5 μm, the cutting efficiency of the prepared cutting wire is low; when the particle size of the diamond particles 31 is larger than 30 μm, on one hand, the deposition of the diamond particles 31 having a particle size larger than 30 μm for a long time will also increase the cost of raw materials for preparing the diamond particles 31; on the other hand, when the cutting line made of the diamond particles 31 having a particle size of more than 30 μm is processed, the wear of the processed workpiece is increased, so that the processed workpiece generates more waste, and the production cost of the processed workpiece is increased.

In some embodiments, the cutting line is further subjected to post-treatment, mainly by processing the surface of the cutting line through a laser cutting device, so as to cut the massive diamond in the diamond layer 30 into uniform particles, and simultaneously, performing laser cutting on the area with the surface growing into a diamond film, so that the area generates concave-convex fluctuation, the cutting efficiency of the cutting line is increased, and the phenomenon that the processing quality of the workpiece is affected due to the inconsistent deposition of the diamond particles 31 on the surface of the cutting line is avoided.

The scheme of the invention will be explained with reference to the examples. It will be appreciated by persons skilled in the art that the following examples are illustrative only and are not to be construed as limiting the invention. Reagents, software and equipment not specifically submitted to the following examples are conventional commercial products or open sources unless otherwise submitted.

Example 1

Taking a plurality of single carbon fibers, wherein the diameter of each carbon fiber is 5-7 microns, putting the plurality of single carbon fibers into an oven, heating to 1000 ℃ under vacuum and argon, and keeping the constant temperature for 2 hours; after cooling, 25 carbon fibers were selected to be woven into a bundle to form a carbon fiber matrix.

Selecting a silicon-titanium alloy as a target source, wherein the mass fraction of silicon is 10%, depositing for 6 hours on a carbon fiber substrate at the deposition temperature of 600 ℃ under normal pressure by a physical vapor deposition method, and depositing a silicon-titanium substrate layer with the thickness of 3 mu m on the carbon fiber substrate.

And (3) placing the carbon fiber substrate deposited with the silicon-titanium substrate layer in a vacuum oven at 1000 ℃, and keeping the temperature constant for 2 hours under the protection of argon gas, so that the silicon-titanium substrate layer and the carbon fiber substrate are fully reacted to generate silicon carbide and titanium carbide, and the bonding force of the silicon-titanium substrate layer and the carbon fiber substrate is improved.

Selecting methane and hydrogen as gas sources, wherein the volume ratio of the methane is 3%, the volume ratio of the hydrogen is 97%, placing the silicon-titanium substrate layer and the carbon fiber substrate which are subjected to the heat treatment at the temperature of 700 ℃ and the pressure of 200torr, and depositing for 6 hours on the silicon-titanium substrate layer through chemical vapor deposition so as to obtain the diamond layer deposited on the silicon-titanium substrate layer. Wherein the diamond particles per square millimeter in the diamond layer are about 700.

And further processing the cutting line, cutting the large-particle diamond on the diamond layer into small particles by using a laser cutting machine, and processing the diamond region with the surface growing into a film shape into an uneven shape to finally obtain the cutting line.

Example 2

Example 2 differs from example 1 in that: the mass fraction of silicon was 20%. In the resulting cutting wire, about 1000 diamond particles per square millimeter of the diamond layer were present. The rest of the procedure was the same as in example 1.

Example 3

Example 3 differs from example 1 in that: the mass fraction of silicon is 30%. In the resulting cutting wire, about 1400 diamond particles per square millimeter of the diamond layer were present.

Example 4

Example 4 differs from example 1 in that: and a plurality of carbon fibers in the carbon fiber matrix are not subjected to high-temperature pretreatment.

Example 5

Example 5 differs from example 1 in that: the carbon fiber matrix with the silicon-titanium substrate layer deposited thereon was not heat treated.

Comparative example 1

Comparative example 1 differs from example 1 in that: the mass fraction of silicon was 3%. In the resulting cutting wire, about 150 diamond particles per square millimeter of the diamond layer were present.

Comparative example 2

Comparative example 2 differs from example 1 in that: the mass fraction of silicon was 55%. In the resulting scribe line, about 2200 diamond particles per square millimeter of diamond layer were present.

Referring to fig. 3, the cutting line prepared in the second embodiment is tested by a scanning electron microscope, and it can be seen that the diamond particles are uniformly distributed.

The cutting experiments of the cutting lines obtained in examples 1-5 and comparative examples 1-2 were also carried out, using a wire cutting device, using silicon rods with a length of 10cm and a diameter of 15cm in the same batch for the workpieces, and the cutting data of the cutting lines obtained in examples 1-5 and comparative examples 1-2 were respectively tested at the same linear speed, the same advancing speed and the same linear tension, and the data are as follows: the time required for cutting the silicon rod into 10 pieces, the service life of a cutting line, the tensile fracture stress and the plating layer falling rate after linear cutting.

Number of diamond particles in diamond layer: in the scanning electron microscope image, the number of diamond particles in a certain area was counted.

Tensile breaking stress test: and measuring the maximum load which can be borne by the cutting line by using an electronic tensile testing machine to obtain tensile fracture stress data.

Service life of the cutting line: when the shedding rate of the cutting line reaches 40%, the working time is judged to be the service life.

Coating shedding rate after wire cutting: and calculating the weight loss of the mass of the cutting line before and after working within a certain time.

TABLE 1 cutting Properties of the cutting lines obtained in examples 1 to 5 and comparative examples 1 to 2

Referring to Table 1, it can be seen that the cutting lines prepared in examples 1-5 all had better cutting efficiency than comparative examples 1-2 when the diamond particles per square millimeter in the cutting lines were in the range of 700, 1000 or 1400, which indicates that the diamond particles per square millimeter in the cutting lines had better cutting efficiency in the range of 200-.

Compared with example 1, the mass fraction of silicon is changed during physical vapor deposition, and if the mass fraction of silicon is 3% as in comparative example 1, and the number of diamond particles per square millimeter in the cutting wire is small, the cutting wire takes longer to cut the silicon rod into 10 pieces, thereby reducing the cutting efficiency of the cutting wire, and meanwhile, because the number of diamond particles is small, each diamond is subjected to a larger force during cutting, the falling of the diamond particles is accelerated, and the service life of the cutting wire may be reduced. In comparative example 2, increasing the mass fraction of silicon increases the number of diamond particles per square millimeter, which causes diamond filming and tends to planarize due to an excessive number of diamond particles per unit area of the surface of the cutting wire, which causes the cutting wire to lose cutting ability, increases the time required for the cutting wire to cut the silicon rod into 10 pieces, and decreases the cutting efficiency of the cutting wire.

The cutting wires obtained in examples 1 to 3 had a long life, and they required a short time to cut the silicon rod into 10 pieces, and their cutting efficiency was high. The number of diamond particles per square millimeter in examples 1-3 was gradually increased as the mass fraction of silicon was increased during the pvd step, thus indicating that the number of diamond particles in the cvd diamond layer could be adjusted by changing the mass fraction of silicon in the target source under the same pvd conditions.

As can be seen from table 1, in comparison between example 1 and example 4, if the carbon fiber substrate is subjected to the high-temperature pretreatment to prepare the cutting line, the tensile breaking stress of the cutting line can be increased, which further indicates that the internal defect of each carbon fiber in the carbon fiber substrate can be effectively eliminated by subjecting the carbon fiber substrate to the high-temperature pretreatment, so as to increase the tensile modulus of the carbon fiber substrate, thereby increasing the service life of the cutting line.

Comparing example 1 with example 5, if the cutting wire is not heat-treated during the process of preparing the cutting wire, the silicon-titanium substrate layer on the surface of the cutting wire is easily separated during cutting the silicon rod due to the small bonding force between the carbon fiber substrate and the silicon-titanium substrate layer during the cutting process, which may cause the falling off of diamond particles on a portion of the cutting wire, thereby reducing the service life of the cutting wire. As shown in the data in Table 1, the peeling rate of the cutting line reaches 3.45%, which is much greater than that of the cutting line after heat treatment. This also shows that the service life of the cutting wire can be effectively increased by the pretreatment and the heat treatment.

Although the present invention has been described in detail with reference to the above embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention.

Claims

1. A method for preparing a cutting wire, comprising:

providing a carbon fiber matrix;

depositing a silicon-titanium substrate layer on the carbon fiber substrate by adopting physical vapor deposition, wherein the mass fraction of silicon in the silicon-titanium substrate layer is 5-50%;

and depositing a diamond layer on the silicon-titanium substrate layer by adopting chemical vapor deposition to obtain the cutting wire, wherein each square millimeter of the diamond layer contains 200-2000 diamond particles.

2. The method of manufacturing a cutting wire according to claim 1, wherein before depositing the diamond layer, the method of manufacturing a cutting wire further comprises:

3. The method for preparing a cutting wire as claimed in claim 1, wherein before depositing the silicon-titanium substrate layer, the method for preparing a cutting wire further comprises:

4. The method for preparing the cutting line as claimed in claim 1, wherein the chemical vapor deposition uses methane and hydrogen as a gas source, the volume ratio of methane is 1% -10%, the volume ratio of hydrogen is 90% -99%, the temperature of the chemical vapor deposition is 600 ℃ -1000 ℃, the pressure is 100-300torr, and the deposition time is 4-10 h.

5. The method for preparing the cutting wire as claimed in claim 1, wherein the PVD process uses a silicon-titanium alloy as a target source, the deposition time is 5-10h, and the deposition temperature is 450-750 ℃.

6. The cutting wire is characterized by comprising a carbon fiber substrate, a silicon-titanium substrate layer arranged on the carbon fiber substrate and a diamond layer arranged on the silicon-titanium substrate layer, wherein at least part of silicon atoms or titanium atoms in the silicon-titanium substrate layer are bonded to the carbon fiber substrate through chemical bonds, the silicon accounts for 5-50% of the mass fraction in the silicon-titanium substrate layer, and each square millimeter in the diamond layer contains 200-2000 diamond particles.

7. The cutting wire of claim 6 wherein said carbon fiber matrix comprises a plurality of individual carbon fibers woven into a bundle.

8. The cutting wire according to claim 7, characterized in that the diameter of the cutting wire is 10-20 μm when the carbon fiber matrix is the single carbon fiber.

9. The dicing wire of claim 6 wherein the silicon-titanium substrate layer has a thickness of 1 to 10 μm.

10. The cutting wire of claim 6 wherein the diamond particles in the diamond layer have a diameter of 5 to 30 μm.