Preparation method of high-strength, high-liquid ultrafine tungsten-based material electroplated diamond wire

Abstract

The present invention relates to a method for preparing an ultra-fine tungsten-based electroplated diamond wire with high strength and high liquid carrying capacity. Rods are made from a specific formula of tungsten powder, molybdenum powder and lanthanum powder, and then go through the steps of swaging, drawing, degreasing, pickling, pre-nickel plating, sanding, two-time curing and drying. During curing I, a nickel-cobalt alloy coating is formed to improve the tensile strength and breaking force, and reduce the risk of wire breakage; curing II obtains a rough crystalline coating to improve the liquid carrying capacity, which is beneficial for chip removal and reduces diamond wear. This method solves the bottleneck problem of wire thinning, and the electroplated diamond wire produced is adapted to the cost reduction needs of the solar photovoltaic power generation industry, has high strength, high wear resistance, good liquid carrying capacity and process stability, can improve the quality and efficiency of silicon wafer cutting, reduce silicon material loss, reduce production costs, and provide strong support for the development of the photovoltaic industry.

Description

Technical Field

[0001] The invention relates to the field of production and preparation of diamond wire saws, and mainly relates to a method for preparing an ultrafine tungsten-based material electroplated diamond wire with high strength and high liquid carrying capacity. Background Art

[0002] With today's growing energy demand and the urgent pursuit of clean energy, solar photovoltaic power generation has rapidly developed as a sustainable energy solution. In the solar photovoltaic power generation industry, efficient silicon wafer cutting is a crucial link, which is directly related to the production quality and cost-effectiveness of solar cells.

[0003] As a key tool for silicon wafer cutting, the performance of electroplated diamond wire has a significant impact on the development of the entire photovoltaic industry. With the continuous advancement of technology, the field of electroplated diamond wire for silicon wafer cutting has been actively promoting wire thinning to further reduce the cost per kilowatt-hour of photovoltaic power generation. Thinning diamond wire can reduce silicon material loss during the cutting process and improve cutting accuracy, thereby increasing the conversion efficiency of solar cells and reducing production costs.

[0004] Tungsten-based materials, due to their unique performance advantages, are increasingly gaining a dominant position in the electroplated diamond wire market as thinning becomes increasingly common. Compared to traditional carbon steel cores, tungsten-based wires offer higher tensile strength, improved torsional fracture resistance, and lower ductility. Specifically, tungsten-based wires have a tensile strength 1.2-1.5 times that of carbon steel cores, 8-12 times the torsional fracture resistance, and only about 60% of the ductility. This allows tungsten-based diamond wires to withstand greater tension during cutting, reducing the risk of wire breakage and improving cutting efficiency.

[0005] However, despite the significant advantages of tungsten-based materials in terms of wire thinning, the current promotion of electroplated diamond wire thinning still faces many challenges. The existing mass-produced electroplated diamond wire process uses carbon steel as the wire core, with a minimum wire core size of 35μm. The finished diamond wire has an outer diameter of 44μm and a breaking force of 5.0N or more. Since the tensile strength of the carbon steel wire core is difficult to meet the cutting tension requirements required for cutting when it is further thinned, it is difficult to continue to promote thinning. The minimum wire core size used for tungsten-based alloy materials is 30μm, with an outer diameter of 39μm and a breaking force of 5.1N or more. Although the tungsten-based material wire core has achieved finer specifications to a certain extent, the further thinning of the wire core has also brought new problems.

[0006] On the one hand, thinner wire cores have lower tensile strength. During the thinning process, the core diameter decreases, and its cross-sectional area also decreases, which in turn reduces the tensile force the core can withstand. When the tensile strength of the core is insufficient, the wire is more likely to break during cutting, affecting production efficiency and product quality.

[0007] On the other hand, thinner wire cores have smaller outer diameters, resulting in more kerfs for the same wire length and thickness. This in turn generates more powder to be removed. If this excess powder isn't removed promptly, it will accumulate in the kerf, increasing cutting resistance, reducing the wire's cutting force, and causing the wire to bow, further increasing the risk of wire breakage. Furthermore, this powder accumulation can affect cutting accuracy and wafer surface quality.

[0008] Currently, silicon wafer cutting companies are constantly striving to reduce wire usage and shorten cutting times to maintain strict cost control. However, while finer tungsten-based alloy wire cores meet these demands, they also face a higher risk of wire breakage. This has temporarily led to a bottleneck in the thinning of electroplated diamond wire. A new preparation method is urgently needed to address these issues and further thin the electroplated diamond wire, thereby improving the efficiency and reducing the cost of solar photovoltaic power generation. Summary of the Invention

[0009] The purpose of the present invention is to provide a method for preparing high-strength, high-liquid-carrying capacity ultrafine tungsten-based electroplated diamond wire to solve the problems encountered in the prior art in the process of advancing the thinning of electroplated diamond wire and improve the performance and service life of the diamond wire.

[0010] A method for preparing high-strength, high-liquid-carrying-capacity ultrafine tungsten-based material electroplated diamond wire comprises the following steps:

[0011] S1 tungsten-based material rod:

[0012] Prepare tungsten powder and molybdenum powder with a purity of ≥99.9%. Mix the powders in a ratio of ≥95wt% tungsten powder, 3.5-4.0wt% molybdenum powder, and 0.3-1.0wt% lanthanum powder. Place the powders in a mold and hot isostatically press them to form an alloy rod.

[0013] S2 rotary forging process:

[0014] The 35 mm diameter alloy rod produced in step S1 was subjected to 25 cycles of rotary forging at a high temperature of 1500°C, with each cycle compressing by 0.8-1.2 mm, to produce a metal wire body with a diameter of 8 mm.

[0015] S3 wire drawing:

[0016] First, in the temperature range of 600-2400℃, different compression amounts are set to perform rough drawing 20-25 times to produce a wire with a diameter of 0.50-0.55mm; then in the temperature range of 200-400℃, different compression amounts are set to perform fine drawing 45-60 times. During the drawing, annealing treatment is carried out at a temperature of 850℃ when the wire is drawn to 0.15mm. After annealing, the wire is continued to produce a wire with a diameter of 0.027mm-0.040mm.

[0017] S4 degreasing treatment:

[0018] The tungsten-based material core is electrolytically degreased in 60g / L electrolytic degreasing solution for 5-8 seconds, with an electrolytic current of 0.8-1.0A. Then, it is degreased in 30g / L chemical degreasing solution for 1-2 seconds to completely remove the grease and oil substances that were not completely removed from the surface of the core during the electrolytic degreasing process.

[0019] S5 pickling:

[0020] Immerse the wire core in a sulfamic acid solution with a pH of 1 for 3-4 seconds to remove the oxide layer on the surface of the wire core.

[0021] S6 pre-nickel plating:

[0022] The core is electrochemically deposited in a nickel sulfamate solution to form a nickel layer with a thickness of 0.02-0.10 μm. The nickel ion concentration of the nickel sulfamate solution used is 85-100 g / L, the boric acid concentration is 28-38 g / L, the nickel chloride concentration is 5-10 g / L, and the current density is 1.0-2.0 A / dm 2 .

[0023] S7 sanding:

[0024] While nickel is being deposited in the nickel sulfamate solution, diamond particles are also deposited onto the wire core that has been pre-nickel-plated. The thickness of the nickel layer plated in the sanding process is 0.5-1.0 μm. The nickel ion concentration of the nickel sulfamate solution is 85-100 g / L, the boric acid concentration is 28-38 g / L, and the nickel chloride concentration is 5.0-10.0 g / L; the diamond particle concentration is 8.0-15.0 ct / L, and the current density is 5.0-10.0 A / dm 2 .

[0025] S8 curing Ⅰ:

[0026] Through electrochemical reaction, the wire core is plated with a 1.0-2.0μm nickel-cobalt alloy in a mixed solution of nickel sulfamate and cobalt sulfamate. The material hardness of cobalt is 1.3-1.7 times that of nickel, and its thermal conductivity is 1.6 times that of nickel. Cobalt also has good corrosion resistance and high temperature resistance, which reduces the risk of wire breakage during cutting. The nickel ion concentration in the electroplating solution used is 85-100g / L, the cobalt ion concentration is 5-15g / L, the boric acid concentration is 28-38g / L, the nickel chloride concentration is 5.0-10.0g / L, and the current density is 10.0-15.0A / dm 2 .

[0027] S9 curing Ⅱ:

[0028] The wire body after solidification I is electrochemically plated in nickel sulfamate solution to form a rough crystalline coating with a thickness of 0.5-1.0 μm. The electroplating solution used contains 65-80 g / L nickel ion concentration, 5.0-15.0 g / L cobalt ion concentration, 25-35 g / L boric acid concentration, and 5.0-10.0 g / L nickel chloride concentration; the current density is 20-30 A / dm 2 The pH is controlled at 4.5-5.0. The rougher nickel coating is more conducive to carrying more cutting fluid during the steel wire cutting process, thereby removing more cutting waste. At the same time, carrying more cutting fluid can also reduce the temperature of the steel wire cutting point, avoid high-temperature carbonization of the diamond, and reduce diamond wear.

[0029] S10 drying:

[0030] The electroplated diamond wire that has completed curing II is washed with 60°C hot water and then placed in a 150-200°C drying device for 2-3 seconds to remove any water stains from the surface of the electroplated diamond wire, thereby obtaining a finished product.

[0031] Beneficial effects of the present invention

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. Improve the performance of diamond wire

[0034] High Strength: The specific formulation of the tungsten-based material during rod formation, followed by swaging and drawing processes, combined with the nickel-cobalt alloy coating formed during curing, gives the diamond wire exceptionally high tensile strength and breaking force. Compared to traditional materials, the tungsten-based core inherently possesses superior mechanical properties. Combined with the strengthening effect of the nickel-cobalt alloy coating, this significantly reduces the risk of wire breakage during use, enabling it to withstand even the most demanding cutting conditions.

[0035] High Wear Resistance: The nickel-cobalt alloy coating and the strong adhesion of the diamond particles give the diamond wire excellent wear resistance during the cutting process. This not only extends the life of the diamond wire, reduces replacement frequency, and lowers production costs, but also ensures cutting stability and consistency, improving the cutting quality of silicon wafers.

[0036] 2. Optimize cutting effect

[0037] Excellent fluid carrying capacity: The rough crystalline coating formed during curing II allows the diamond wire to carry more cutting fluid. During the cutting process, more cutting fluid can better remove cutting waste, reducing waste interference, lowering cutting resistance, and improving cutting efficiency. The cutting fluid also lowers the temperature at the wire cutting point, preventing high-temperature carbonization of the diamond, reducing diamond wear, maintaining diamond sharpness, and further improving cutting results.

[0038] Reduced wire bow: The high strength and excellent liquid-carrying capacity of diamond wire can reduce wire bow during the cutting process. This means more precise cutting and better wafer thickness uniformity, improving wafer quality and yield.

[0039] 3. Adapt to the needs of thin lines

[0040] Breaking through the bottleneck of wire thinning: With the solar photovoltaic power generation industry's pursuit of cost reduction, the thinning of electroplated diamond wire used in silicon wafer cutting is an inevitable trend. The preparation method of this invention can produce ultra-fine tungsten-based electroplated diamond wire, solving the problems of low tensile strength of the substrate and difficulty in chip removal in thinner wire cores, providing a feasible solution for the advancement of thinning of electroplated diamond wire.

[0041] Meeting Cost Control Requirements: Thinner diamond wire reduces silicon material loss, improves cutting accuracy, and reduces wire usage and cutting time, meeting the stringent cost control requirements of silicon wafer cutting companies. Furthermore, the preparation method of the present invention enables efficient production while maintaining performance, further reducing production costs.

[0042] 4. Process stability and reliability

[0043] Precise process control: Clearly defined process parameters and operating requirements are implemented for each step, from tungsten-based material rod making to drying. Strict process control ensures stable and consistent product quality, reduces uncertainty during production, and improves production efficiency and yield.

[0044] Excellent coating adhesion: Through pre-nickel plating, sanding, and curing processes, excellent adhesion is achieved between the coating and the wire core, as well as between the diamond particles and the coating. This ensures that the coating and diamond particles will not easily fall off during use, improving the reliability and service life of the diamond wire. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The foregoing and following detailed description of the present invention will become more apparent when read in conjunction with the following drawings, in which: Figure 1 The present invention relates to a step diagram of a method for preparing a high-strength, high-liquid-carrying-capacity ultrafine tungsten-based material electroplated diamond wire.

[0046] Figure 2 It is a normal smooth coating of the prior art non-curing II process involved in the present invention.

[0047] Figure 3 The present invention relates to an improved rough coating with a curing II process. DETAILED DESCRIPTION

[0048] To make the purpose, technical solutions and advantages of the examples of the present application clearer, the technical solutions in the examples of the present application will be described clearly and completely below. Where specific conditions are not specified in the examples, conventional conditions or conditions recommended by the manufacturer are used. Where the manufacturer of the reagents or instruments is not specified, they are all conventional products that can be purchased commercially.

[0049] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to specific embodiments.

[0050] Example 1:

[0051] A method for preparing high-strength, high-liquid-carrying-capacity ultrafine tungsten-based material electroplated diamond wire comprises the following steps:

[0052] S1 tungsten-based material rod:

[0053] Prepare tungsten powder and molybdenum powder with a purity of ≥99.9%. Mix the powders in a ratio of ≥95wt% tungsten powder, 3.5-4.0wt% molybdenum powder, and 0.3-1.0wt% lanthanum powder. Place the powders in a mold and hot isostatically press them to form an alloy rod.

[0054] S2 rotary forging process:

[0055] The 35 mm diameter alloy rod produced in step S1 was subjected to 25 cycles of rotary forging at a high temperature of 1500°C, with each cycle compressing by 0.8-1.2 mm, to produce a metal wire body with a diameter of 8 mm.

[0056] S3 wire drawing:

[0057] First, in the temperature range of 600-2400℃, different compression amounts are set to perform rough drawing 20-25 times to produce a wire with a diameter of 0.50-0.55mm; then in the temperature range of 200-400℃, different compression amounts are set to perform fine drawing 45-60 times. During the drawing, annealing treatment is carried out at a temperature of 850℃ when the wire is drawn to 0.15mm. After annealing, the wire is continued to produce a wire with a diameter of 0.027mm-0.040mm.

[0058] S4 degreasing treatment:

[0059] The tungsten-based material core is electrolytically degreased in 60g / L electrolytic degreasing solution for 5-8 seconds, with an electrolytic current of 0.8-1.0A. Then, it is degreased in 30g / L chemical degreasing solution for 1-2 seconds to completely remove the grease and oil substances that were not completely removed from the surface of the core during the electrolytic degreasing process.

[0060] S5 pickling:

[0061] Immerse the wire core in a sulfamic acid solution with a pH of 1 for 3-4 seconds to remove the oxide layer on the surface of the wire core.

[0062] S6 pre-nickel plating:

[0063] The core is electrochemically deposited in a nickel sulfamate solution to form a nickel layer with a thickness of 0.02-0.10 μm. The nickel ion concentration of the nickel sulfamate solution used is 85-100 g / L, the boric acid concentration is 28-38 g / L, the nickel chloride concentration is 5-10 g / L, and the current density is 1.0-2.0 A / dm 2 .

[0064] S7 sanding:

[0065] While nickel is being deposited in the nickel sulfamate solution, diamond particles are also deposited onto the wire core that has been pre-nickel-plated. The thickness of the nickel layer plated in the sanding process is 0.5-1.0 μm. The nickel ion concentration of the nickel sulfamate solution is 85-100 g / L, the boric acid concentration is 28-38 g / L, and the nickel chloride concentration is 5.0-10.0 g / L; the diamond particle concentration is 8.0-15.0 ct / L, and the current density is 5.0-10.0 A / dm 2 .

[0066] S8 curing Ⅰ:

[0067] Through electrochemical reaction, the wire core is plated with a 1.0-2.0μm nickel-cobalt alloy in a mixed solution of nickel sulfamate and cobalt sulfamate. The material hardness of cobalt is 1.3-1.7 times that of nickel, and its thermal conductivity is 1.6 times that of nickel. Cobalt also has good corrosion resistance and high temperature resistance, which reduces the risk of wire breakage during cutting. The nickel ion concentration in the electroplating solution used is 85-100g / L, the cobalt ion concentration is 5-15g / L, the boric acid concentration is 28-38g / L, the nickel chloride concentration is 5.0-10.0g / L, and the current density is 10.0-15.0A / dm 2 .

[0068] S9 curing Ⅱ:

[0069] Through an electrochemical reaction, the cured wire is coated with a rough, crystalline layer 0.5-1.0μm thick in a nickel sulfamate solution. The electroplating solution contains 65-80g / L nickel ion concentrations, 5.0-15.0g / L cobalt ion concentrations, 25-35g / L boric acid concentrations, and 5.0-10.0g / L nickel chloride concentrations. The current density is 20-30A / dm², and the pH is controlled at 4.5-5.0. The rougher nickel coating facilitates the transport of more cutting fluid during the wire cutting process, thereby removing more cutting waste. This increased fluid transport also lowers the temperature at the wire cutting point, preventing high-temperature carbonization of the diamond and reducing diamond wear.

[0070] S10 drying:

[0071] The electroplated diamond wire that has completed curing II is washed with 60°C hot water and then placed in a 150-200°C drying device for 2-3 seconds to remove any water stains from the surface of the electroplated diamond wire, thereby obtaining a finished product.

[0072] Example 2:

[0073] Preparation of high-strength and high-liquid-carrying ultrafine tungsten-based electroplated diamond wire

[0074] 1. Raw material preparation

[0075] According to the invention's requirements, prepare tungsten powder, molybdenum powder, and lanthanum powder with a purity of ≥99.9%. Accurately weigh the tungsten powder to ensure a purity of ≥95% by weight, the molybdenum powder to approximately 3.8% by weight, and the lanthanum powder to 0.5% by weight. Thoroughly mix these powders to ensure stable properties of the resulting alloy.

[0076] 2. Tungsten-based material rods (S1)

[0077] The uniformly mixed powder is placed in a specially designed mold and hot isostatically pressed. Under high temperature and pressure, the powder particles are tightly bonded together to form an alloy rod. The hot isostatically pressed rod has a uniform microstructure and excellent mechanical properties.

[0078] 3. Rotary forging process (S2)

[0079] A 35mm diameter alloy rod is placed in a rotary swaging machine and subjected to a high temperature of 1500°C. This process is repeated 25 times, with each compression controlled to approximately 1mm. The diameter of the alloy rod is gradually reduced through rotary swaging, while the material's grain size is refined, further improving its strength and toughness. The final result is a metal wire with a diameter of 8mm.

[0080] 4. Wire drawing (S3)

[0081] Rough drawing: First, the wire is drawn 22 times at a temperature between 1000-2000°C, with different compression levels set at different stages. After rough drawing, the wire diameter is reduced to about 0.52mm.

[0082] Annealing treatment: When the wire is drawn to a diameter of 0.15mm, annealing treatment is carried out. The wire is placed in an annealing furnace at a temperature of 850℃ and kept warm for a period of time to eliminate the internal stress generated during the drawing process.

[0083] Fine drawing: After annealing, fine drawing is continued at a temperature range of 250-350°C. After about 50 fine drawing cycles, the wire diameter is finally drawn to 0.03mm.

[0084] 5. Oil removal treatment (S4)

[0085] Electrolytic degreasing: Place the tungsten-based material core in 60g / L electrolytic degreasing solution and pass an electrolytic current of 0.9A for 6 seconds. The electrode polarization will quickly remove the oil stains on the core surface.

[0086] Chemical degreasing: Then place the wire core in 30g / L chemical degreasing liquid for 1.5 seconds to completely remove the grease and oil substances that have not been completely peeled off from the surface of the wire core.

[0087] 6. Pickling (S5)

[0088] Immerse the wire core in a sulfamic acid solution with a pH of 1 for 3.5 seconds to remove the oxide layer on the surface of the wire core and prepare for the subsequent nickel plating deposition.

[0089] 7. Pre-nickel plating layer (S6)

[0090] The core is electrochemically deposited in a nickel sulfamate solution. The nickel ion concentration in the solution is 90g / L, the boric acid concentration is 32g / L, the nickel chloride concentration is 8g / L, and the current density is controlled at 1.5A / dm 2 After a period of deposition, a uniform nickel layer with a thickness of 0.06 μm is formed on the surface of the wire core.

[0091] 8. Sanding (S7)

[0092] In a nickel sulfamate solution, nickel deposition and diamond particle deposition are carried out simultaneously. The nickel ion concentration in the solution is 90g / L, the boric acid concentration is 32g / L, the nickel chloride concentration is 8g / L, the diamond particle concentration is 10ct / L, and the current density is 8A / dm 2 After the sanding process is completed, the thickness of the nickel layer on the surface of the wire core reaches 0.8μm, and the diamond particles are evenly distributed on the nickel layer.

[0093] IX. Curing I (S8)

[0094] Through electrochemical reaction, the wire core is solidified in a composite solution of nickel sulfamate and cobalt sulfamate. The nickel ion concentration in the solution is 90g / L, the cobalt ion concentration is 10g / L, the boric acid concentration is 32g / L, the nickel chloride concentration is 8g / L, and the current density is 12A / dm 2 After solidification, a nickel-cobalt alloy coating with a thickness of 1.5 μm is formed on the surface of the wire core.

[0095] 10. Curing II (S9)

[0096] The wire body that has completed curing I is cured for the second time in a nickel sulfamate solution. The nickel ion concentration in the solution is 70g / L, the cobalt ion concentration is 10g / L, the boric acid concentration is 30g / L, the nickel chloride concentration is 8g / L, and the current density is 25A / dm 2 , the pH is controlled at 4.8. After curing, a rough crystalline coating with a thickness of 0.8 μm is formed on the surface of the wire.

[0097] 11. Drying (S10)

[0098] The electroplated diamond wire that has completed curing II is washed with hot water at 60°C and then dried in a drying device at 180°C for 2.5 seconds. After drying, no water stains remain on the surface of the diamond wire, thus obtaining a finished product.

[0099] The above is a preferred embodiment of the present invention, but the present invention is not limited to the above embodiment. Without departing from the principle of the present invention, those skilled in the art can make various equivalent substitutions and improvements to the present invention, and these substitutions and improvements should be included in the scope of protection of the present invention.

Claims

1. A method for preparing high-strength, high-liquid-carrying ultrafine tungsten-based electroplated diamond wire, characterized in that: The following steps are involved: S1 Tungsten-based material rod making: Prepare tungsten powder and molybdenum powder with a purity of ≥99.9%; according to the formula ratio of tungsten powder ≥95wt%, molybdenum powder 3.5-4.0wt%, and lanthanum powder 0.3-1.0wt%, mix the above powders evenly, place them in a mold, and then hot isostatically press them to form an alloy material rod; S2 rotary forging process: The 35mm diameter alloy rod produced in step S1 is subjected to 25 cycles of rotary forging at 1500°C, with each cycle compressing 0.8-1.2mm to produce a metal wire with a diameter of 8mm. S3 wire drawing: First, rough drawing is performed 20-25 times at different compressions within the temperature range of 600-2400°C to produce a wire with a diameter of 0.50-0.55mm. Then, fine drawing is performed 45-60 times at different compressions within the temperature range of 200-400°C. During the drawing process, annealing is performed at 850°C when the wire is drawn to 0.15mm. After annealing, drawing is continued until the wire diameter reaches 0.027mm-0.040mm. S4 Degreasing Treatment: Electrolytically degrease the tungsten-based material core in 60g / L electrolytic degreasing solution for 5-8 seconds, with an electrolytic current of 0.8-1.0A. Then degrease in 30g / L chemical degreasing solution for 1-2 seconds to completely remove any grease or oil that was not completely removed from the core surface during the electrolytic degreasing process. S5 pickling: Immerse the wire core in a sulfamic acid solution with a pH of 1 for 3-4 seconds to remove the oxide layer on the surface of the wire core; S6 Pre-nickel plating: The wire core is electrochemically deposited in a nickel sulfamate solution to complete the nickel layer deposition of 0.02-0.10μm thickness. The nickel ion concentration of the nickel sulfamate solution used is 85-100g / L, the boric acid concentration is 28-38g / L, the nickel chloride concentration is 5-10g / L, and the current density is 1.0-2.0A / dm 2 ; S7 Sanding: While nickel is being deposited in the nickel sulfamate solution, diamond particles are also deposited onto the pre-nickel-plated wire core. The nickel layer thickness in the sanding process is 0.5-1.0μm. The nickel ion concentration of the nickel sulfamate solution is 85-100g / L, the boric acid concentration is 28-38g / L, and the nickel chloride concentration is 5.0-10.0g / L; the diamond particle concentration is 8.0-15.0ct / L, and the current density is 5.0-10.0A / dm 2 ; S8 Curing I: Through electrochemical reaction, the wire core is plated with a 1.0-2.0μm nickel-cobalt alloy layer in a mixed solution of nickel sulfamate and cobalt sulfamate; the nickel ion concentration in the plating solution used is 85-100g / L, the cobalt ion concentration is 5-15g / L, the boric acid concentration is 28-38g / L, the nickel chloride concentration is 5.0-10.0g / L, and the current density is 10.0-15.0A / dm 2 ; S9 Curing II: The wire that has completed Curing I is electrochemically plated in a nickel sulfamate solution to form a rough crystalline coating with a thickness of 0.5-1.0 μm. The plating solution used has a nickel ion concentration of 65-80 g / L, a cobalt ion concentration of 5.0-15.0 g / L, a boric acid concentration of 25-35 g / L, and a nickel chloride concentration of 5.0-10.0 g / L. The current density is 20-30 A / dm 2 , pH control 4.5 - 5.0; S10 Drying: The electroplated diamond wire that has completed curing II is washed with 60°C hot water and then placed in a 150-200°C drying device for 2-3 seconds to remove any water stains from the surface of the electroplated diamond wire, thereby obtaining the finished product.

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