Ultrathin diamond dicing blade with microporous structure and preparation method of ultrathin diamond dicing blade

Abstract

The invention discloses an ultrathin diamond dicing blade with a microporous structure and a preparation method thereof. Diamond particles, a binding agent, a binder and a pore-forming agent with the particle size of micron order are prepared and mixed to obtain a mixture; the mixture is subjected to banburying, pelletizing and wire making, a dicing blade wire is obtained, then the dicing blade wire is placed in a 3D printer to be printed, a green body is obtained, the green body is degreased and sintered, and a sintered sample is obtained; and carrying out post-treatment on the sintered sample to remove the pore-forming agent, thereby obtaining the product. The pore-forming agent comprises an inorganic salt pore-forming agent or a hollow microsphere pore-forming agent; micropores in the ultrathin diamond dicing blade with the micropore structure are distributed on the ultrathin diamond dicing blade base body in a discrete mode. By selecting the specific pore-forming agent and combining with the 3D printing technology, the pore-forming agent particles are uniformly distributed in the dicing blade, the problems of overheat grinding, insufficient self-sharpening and the like caused by lack of pores of the metal matrix dicing blade are effectively solved, and the performance of the dicing blade is enhanced, so that the dicing blade can cope with higher feeding speed and more stringent cutting conditions.

Description

Technical Field

[0001] This invention belongs to the field of superhard material preparation technology, and specifically relates to a method for preparing an ultrathin diamond dicing blade with a microporous structure. Background Technology

[0002] Diamond dicing is a superhard cutting tool that uses diamond as an abrasive. Thanks to the high hardness, high wear resistance and high thermal conductivity of diamond, diamond dicing has become the most widely used wafer cutting method. It is an important tool in the production process of industries such as semiconductors, electronic circuits and precision machining.

[0003] Diamond dicing blades are composed of diamond particles and a binder. Based on the material and bonding method, they are classified into three types: metal dicing blades, resin dicing blades, and electroplated dicing blades. Resin dicing blades have relatively poor wear resistance and a larger dicing thickness, typically used for light cutting and scraping, but with a shorter service life. Electroplated dicing blades use an electroplating and sandblasting process, which can meet higher cutting precision requirements, but demands sophisticated production equipment and processes. Metal dicing blades, on the other hand, have strong diamond holding power, resulting in high wear resistance and a longer service life. Their manufacturing process generally involves mixing raw material powders, molding them, and then hot-pressing and sintering them, requiring multiple post-processing steps and incurring higher manufacturing costs.

[0004] Diamond dicing blades contain diamond particles encased in a metal / non-metal bond. During cutting, continuous wear exposes new particles, causing the surface diamond particles to protrude and form a structure called a "chip groove" with the bond. This chip groove digs into the object being cut and removes cutting debris. The debris generated during cutting can clog and adhere to the dicing blade, not only reducing its self-sharpening ability and cutting capacity but also affecting heat dissipation and shortening its lifespan. Therefore, it is crucial to prevent chip adhesion and properly treat the chips during cutting to ensure the dicing blade functions correctly throughout the process.

[0005] Although there is currently little research on optimizing chip removal and heat dissipation for diamond dicing cutters, and even less on methods for uniformly distributing microporous structures on ultrathin diamond dicing cutters, based on research on diamond dicing cutters and the porosity of diamond tools such as diamond grinding wheels and diamond drill bits, microporous structures are one of the important directions for optimizing the cutting quality and lifespan of diamond dicing cutters. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, the first objective of this invention is to provide an ultrathin diamond dicing blade with a microporous structure. The discrete and uniformly distributed microporous structure achieves optimized effects such as reduced friction and wear, vibration reduction and anti-adhesion, and improves chip removal and heat dissipation during the cutting process, thereby significantly improving the tool's service life and dicing quality. Furthermore, the ultrathin thickness of the dicing material gives it high sharpness.

[0007] The second objective of this invention is to provide a method for preparing an ultrathin diamond dicing blade with a microporous structure. By adding a certain pore-forming agent and combining it with the melt-sinking molding technology based on the extrusion molding principle in 3D printing, a uniform distribution of the microporous structure and controllable porosity can be achieved. At the same time, compared with laser ablation or chemical etching, this preparation method is low in cost, highly operable, and has good prospects for large-scale application.

[0008] To achieve the above objectives, this invention provides a method for preparing an ultrathin diamond dicing blade with a microporous structure. The method involves mixing diamond particles, a binder, a binder, and a pore-forming agent with a particle size in the micrometer range to obtain a mixture. This mixture is then subjected to intensive mixing, granulation, and filament forming to obtain dicing blade filaments. These filaments are then placed in a 3D printer to obtain a green blank. The green blank is degreased and sintered to obtain a sintered sample. The sintered sample undergoes post-treatment to remove the pore-forming agent, yielding the final product. The pore-forming agent includes inorganic salt pore-forming agents or hollow microsphere pore-forming agents. In the ultrathin diamond dicing blade with a microporous structure, the micropores are discretely distributed on the ultrathin diamond dicing blade matrix.

[0009] The key innovation of this invention is that by adding a specific pore-forming agent and combining it with 3D printing technology, the pore-forming agent can be uniformly distributed discretely on the dicing blade, resulting in an ultra-thin dicing blade. Specifically, this invention first adds a micron-sized pore-forming agent to the mixture, then uniformly mixes the pore-forming agent with diamond particles through a mixing process. The pore-forming agent is then uniformly fixed into the dicing blade using 3D printing technology. Finally, the pore-forming agent is removed through post-processing technology, thus forming a uniformly distributed microporous structure on the dicing blade. This improves chip removal and heat dissipation during the cutting process, significantly extending the lifespan of the dicing blade. Furthermore, the use of 3D printing technology allows for high-precision dicing blade structure design, resulting in ultra-thin dicing blades, thereby greatly improving the accuracy and stability of the dicing process.

[0010] Another feature of this invention is that different types of pore-forming agents and post-treatment methods can be selected according to the application scenario. The inorganic salt pore-forming agent is selected from NaCl or KCl particles, and the hollow microsphere pore-forming agent is selected from Al2O3 hollow spheres or glass hollow spheres. NaCl, with its melting point of 801℃, is compatible with the sintering temperature of diamond dicing blades, producing regular honeycomb-like pores. Furthermore, it can be completely removed by water immersion after sintering, making NaCl a commonly used inorganic salt pore-forming agent. KCl, with a melting point of 770℃, reacts with active metals (such as Co and Ni) to form low-melting-point eutectic phases, and is therefore only used in scenarios requiring closed-pore structures and lower cutting requirements. The hollow microsphere pore-forming agent forms a porous structure through self-fracture during grinding, releasing new sharp edges and achieving a self-sharpening effect. Alumina hollow spheres possess excellent high-temperature stability and chemical inertness, and their coefficient of thermal expansion matches that of the metal binder, making them less prone to microcracks during fabrication. Therefore, alumina hollow spheres maintain morphological stability and form regular closed-cell structures during fabrication. In contrast, glass hollow spheres soften at high temperatures in the sintering zone, potentially deforming slightly and forming semi-open-cell structures with some porosity fluctuations. This makes them suitable for large-scale porosity adjustment or rough machining. More importantly, the specific pore-forming agent used in this invention is more easily integrated into the 3D printing process and maintains stable performance during subsequent debinding and sintering processes. It can be removed later through water bath dissolution or post-treatment to control the final micropore size and distribution.

[0011] As a preferred embodiment, the 3D printing uses a melt extrusion 3D printer. In actual use, a model of the overall structure of the ultrathin diamond dicing blade is pre-drawn in a computer, the model is imported into the printer's slicing software to set printing parameters, and then imported into the 3D printer; the dicing blade filament is placed into the printer for printing to obtain an ultrathin diamond dicing blade green blank with a microporous structure.

[0012] As a preferred embodiment, when the pore-forming agent is an inorganic salt pore-forming agent, the post-treatment involves removing the pore-forming agent by water bath dissolution; when the pore-forming agent is a hollow microsphere pore-forming agent, the post-treatment involves removing the pore-forming agent by at least one of grinding dressing, electrical discharge dressing, laser polishing dressing, and ultrasonic-assisted micro-grinding dressing. For precision machining, laser polishing dressing or ultrasonic-assisted micro-grinding is preferred, while for high-efficiency rough machining, electrical discharge dressing or soft elastic grinding dressing can be selected.

[0013] As a preferred embodiment, the inorganic salt pore-forming agent includes at least one of NaCl and KCl, with a particle size of 0.1 μm to 500 μm, more preferably 1 to 100 μm. Experiments have shown that within the material system and porosity range used in ultra-thin diamond dicing blades, the pore size can be considered approximately 1.2 × pore-forming agent particle size. The particle size not only affects the size of the micropore structure but also the processing difficulty and the mechanical properties of the dicing blade. If the inorganic salt pore-forming agent particle size is too small, it is prone to agglomeration; if the particle size is too large, it will lead to localized stress concentration in the tool, causing chipping and significantly affecting the bending strength of the dicing blade. Therefore, depending on the required precision for different cutting scenarios, chipping needs to be strictly controlled in precision cutting, in which case a particle size of 0.5 μm to 2 μm is further preferred; while in high-efficiency roughing, the chip removal and chip-holding capacity of the dicing blade need to be improved, so in this case, the average particle size of the inorganic salt pore-forming agent is further preferably 20 μm to 100 μm.

[0014] As a preferred embodiment, the hollow microsphere pore-forming agent comprises at least one of Al2O3 hollow spheres and glass hollow spheres, with a particle size of 0.1 μm to 200 μm, more preferably 0.1 to 100 μm. Because the alumina hollow sphere pore-forming agent produces excellent pore uniformity and is available in advanced technology for preparing nano-ceramic hollow spheres, its average particle size of 0.1 μm to 10 μm is suitable for most precision cutting applications. In contrast, the glass hollow sphere pore-forming agent has a slightly larger particle size but lower cost, with an average particle size of 100 μm to 200 μm, making it suitable for low-cost, high-efficiency rough machining cutting applications.

[0015] As a preferred embodiment, the specific process of water bath dissolution is as follows: the sintered sample is immersed in distilled water at 60~80℃ for 2~8 hours, then ultrasonically cleaned for 20~60 minutes at 20~50kHz, rinsed with distilled water, and then dried.

[0016] As a preferred embodiment, the mixture comprises the following components by volume fraction: 30-60% binder, 0.5-25% pore-forming agent, 5-35% diamond particles, and the balance being a binder.

[0017] In this invention, the volume fraction of the pore-forming agent needs to be strictly controlled to balance the mechanical properties and heat dissipation efficiency of the dicing blade. Specifically, the microporous structure in the ultra-thin diamond dicing blade can improve the heat dissipation efficiency and chip-holding capacity of the blade and optimize its self-sharpening properties. However, at the same time, the bending strength, hardness, and service life decrease with the increase of porosity. Therefore, the porosity needs to be controlled according to the application scenario. When the volume fraction of the pore-forming agent is too large, it will cause a decrease in the mechanical properties of the dicing blade. When the volume fraction of the pore-forming agent is too small, it cannot effectively improve the heat dissipation efficiency and chip-holding capacity of the dicing blade. Experiments have shown that the influence of the microporous structure can be well balanced within a porosity range of 5% to 20%. The preferred volume fraction of the pore-forming agent is 8% to 15%, and even more preferably 10% to 18.75%.

[0018] As a preferred embodiment, the adhesive comprises, by weight percentage, the following components: 30-75% styrene-butadiene block copolymer, 5-35% polyurethane, 5-10% polyvinyl alcohol formaldehyde, 3-6% acrylonitrile-butadiene-styrene copolymer, 3-6% phthalate, and 0.1-0.4% stearic acid.

[0019] The binder of this invention uses a styrene-butadiene block copolymer as the backbone component, which combines elasticity and plasticity with good tensile strength, providing the filament with sufficient flowability and toughness. Polyurethane, with its strong polar groups, readily forms hydrogen bonds or weak chemical bonds with the metal binder powder, contributing to improved mixing uniformity and filament strength. An appropriate amount of polyvinyl formal not only improves powder dispersibility but also increases the mechanical strength of the filament. The acrylonitrile-butadiene-styrene copolymer, together with phthalates, regulates the flowability of the filament, ensuring it does not break during extrusion molding. Stearic acid, though present in a low proportion, is an important lubricant and release agent, reducing friction between the mixture and the screw during mixing, granulation, and filament forming. The above binder system collectively regulates the viscosity, hardness, flowability, and toughness of the filament, ensuring a uniform and high-quality green body after printing.

[0020] As a preferred embodiment, the binder, by mass fraction, comprises: 40%~100% copper-tin alloy, with the balance being M; wherein M is selected from at least one of tungsten carbide, cobalt, iron, nickel, titanium, chromium, zinc, and boron. By adding a certain amount of copper-tin alloy as the main binder to the mixture of the present invention, the lower melting point of the alloy can reduce the temperature of the sintering process, thereby reducing the risk of thermal damage (graphitization) to diamond at high temperatures, maintaining the hardness and sharpness of the diamond, and simultaneously increasing the density of the material to a certain extent. Furthermore, it can improve the thermal conductivity of the dicing during use.

[0021] As a preferred embodiment, the diamond particles have a particle size of 1~450μm, and the binder has a particle size of ≤450μm.

[0022] In the actual operation of 3D printing, using diamond particles and binder powder within the particle size range of this invention can simultaneously ensure material uniformity and printing accuracy. If the raw material particle size is too small, agglomeration will occur, affecting the uniformity of the dicing blade; if it is too large, it will reduce printing accuracy and affect the density of the dicing blade. Furthermore, depending on the application scenario, appropriate diamond and pore-forming agent particle sizes must be selected, and the pore diameter created by the pore-forming agent should not exceed the diamond particle size. Therefore, for precision cutting, a further preferred diamond particle size is 3~20μm and a pore size is 0.5~10μm; for high-efficiency roughing, a further preferred diamond particle size is 20~100μm and a pore size is 20~100μm. A further preferred binder particle size is 20~100μm.

[0023] As a preferred embodiment, the mixing, granulation, and drawing temperatures are all 100~300°C, and the drawing speed is 10~200 rpm, to control the diameter of the dicing filaments to be 1.65~1.85 mm. In actual operation, the mixture is placed in a mixer for mixing to obtain feedstock, which is then placed in a granulator for granulation. The granules are then placed in a drawing machine to obtain dicing filaments with a diameter of 1.75 mm ± 0.10 mm.

[0024] As a preferred embodiment, the 3D printing process parameters are: layer thickness 0.01~0.2mm, extrusion rate 10~300mm / s, and printing temperature 100~300℃. Layer thickness affects interlayer bonding performance. To ensure green body accuracy and interlayer adhesion, this invention requires selecting an appropriate single-layer thickness based on the finished product thickness. Extrusion speeds that are too fast are prone to filament breakage and unstable extrusion, while speeds that are too slow can cause binder evaporation and uneven flow. The printing temperature of this invention is similar to the filament preparation temperature and mainly depends on the filament flowability.

[0025] As a preferred embodiment, the degreasing is carried out under a hydrogen atmosphere, and the degreasing process is as follows: the temperature is increased from room temperature to 80-120°C at a rate of 5-10°C / min, and held for 0.5-1 h; then the temperature is increased to 180-230°C at a rate of 1-5°C / min, and held for 1-2.5 h; then the temperature is increased to 280-320°C at a rate of 1-5°C / min, and held for 0.5-1.5 h; then the temperature is increased to 330-380°C at a rate of 1-5°C / min, and held for 0.5-1.5 h; then the temperature is increased to 420-480°C at a rate of 1-5°C / min, and held for 0.5-1.5 h; finally, the temperature is increased to 500-620°C at a rate of 2-6°C / min, and held for 0.5-1 h. The thermal degreasing process of this invention employs a slow, stepwise heating and heat preservation degreasing process under a hydrogen reducing atmosphere. This setup not only ensures asynchronous degreasing based on the decomposition temperature range of the binder, guaranteeing the binder removal effect and avoiding degreasing defects, but also keeps the degreased blank intact. Simultaneously, the slow heating and heat preservation process reduces the breakage of the pore-forming agent and effectively controls its impact.

[0026] As a preferred embodiment, the sintering conditions are: temperature of 650~900℃, sintering pressure of 5~20MPa, and holding time of 120~600s. After holding, the pressure is slowly released and the temperature is lowered to obtain an ultra-thin diamond dicing blade sintered sample with a microporous structure. The hot-pressing sintering used in this invention can eliminate residual internal porosity to the maximum extent, and the pore-forming agent can be protected to maintain morphological stability within this temperature range. Therefore, sintering can be achieved without excessively high temperatures.

[0027] After the pore-forming agent is removed by post-treatment, the surface of the ultra-thin diamond scribing blade of the present invention is relatively rough, and it can be finely processed by grinding, polishing and cutting.

[0028] The present invention also provides an ultrathin diamond dicing blade with a microporous structure, which is obtained by the above preparation method.

[0029] As a preferred embodiment, the pore size of the micropores in the microporous structure is 1.2 times the particle size of the pore-forming agent; and the thickness of the diamond dicing blade is ≤2mm. In this invention, the small pore size and thin blade thickness, when discretely distributed, are more conducive to maintaining the cutting efficiency and sharpness of the dicing blade.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The ultra-thin diamond dicing blade with microporous structure of the present invention achieves the optimized effects of reducing friction, reducing wear, reducing vibration and preventing adhesion through the discrete and uniformly distributed microporous structure, and improves the chip removal and heat dissipation effect during the cutting process, thereby greatly improving the tool life and dicing quality. Moreover, the ultra-thin thickness of the dicing material gives it more precise application scenarios, enabling it to cope with higher feed speeds and more stringent cutting conditions.

[0032] (2) The present invention adopts fused deposition modeling 3D printing process and adds specific pore-forming agents, which can not only maintain the properties and structure of the pore-forming agent itself and ensure the uniform distribution of the pore-forming agent, but also adjust the porosity, pore size or layered structure according to the usage requirements. This not only enables the personalized design of microporous structure dicing blades at low cost, but also improves production efficiency and reduces production costs.

[0033] (3) The present invention can be combined with different types of pore-forming agents and post-treatment methods according to the application scenario, and the process method is flexible.

[0034] (4) Compared with laser ablation or chemical etching, the method of the present invention is low in cost, highly operable, and has good prospects for large-scale application.

[0035] (5) The micropores on the ultra-thin diamond dicing blade of the present invention have small particle size and thickness of less than 2 mm. The cutting efficiency is increased by 15-43% compared with conventional dicing blades, the self-sharpening property is increased by 20-30%, and the service life is extended by 8-30%. Attached Figure Description

[0036] Figure 1 This is a photograph of the ultrathin diamond dicing blade with a microporous structure prepared in Example 1 of the present invention. Detailed Implementation

[0037] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments.

[0038] Example 1

[0039] Design an ultrathin diamond dicing blade with NaCl as a pore-forming agent, measuring Φ58×0.30×40mm. The diamond particle concentration is 20 vol%; the NaCl pore-forming agent concentration is 10 vol%; the total volume concentration of the binder is 30 vol%; and the remainder is binder. The binder composition is 70 vol% CuSn. 10The components are 20 vol% Co and 10 vol% WC; the binder composition is 54.9 wt% styrene-butadiene block copolymer, 30 wt% polyurethane, 5 wt% polyvinyl formal, 5 wt% acrylonitrile-butadiene-styrene copolymer, 5 wt% phthalate, and 0.1 wt% stearic acid. The diamond particle size is 125~150 μm, the NaCl pore-forming agent powder particle size is 100 μm, and the binder powder particle size is 100~120 μm.

[0040] This example provides a 3D printing process for an ultrathin diamond dicing blade with a microporous structure, including the following steps:

[0041] 1) Preparation of printing filament: Weigh diamond particles, micron-sized pore-forming agent powder, binder powder and adhesive according to the design ratio, mix them evenly and put them into an internal mixer for thorough mixing. Put the resulting feed into a granulator to granulate, and then put the granules into a wire drawing machine to extrude filaments with a diameter of 1.75mm±0.10mm. The mixing, granulation and wire drawing temperatures are all 200℃ and the rotation speed is 80rpm.

[0042] 2) Printing model and parameter design: Draw the model of the ultrathin diamond dicing blade with the microporous structure in the computer, import the model into the dicing software to set the printing parameters, and then export the printing file; the printing parameters are: nozzle diameter 1mm, printing layer thickness 0.5mm, extrusion rate 50mm / s, flow rate 100%, and printing temperature 200℃.

[0043] 3) Green printing: Import the printing file into the 3D printer, put the filament into the printer feed port, and start the printer to print a green blank of an ultra-thin diamond dicing blade with a microporous structure;

[0044] 4) Green body debinding: The obtained green body is placed into a graphite mold and then placed in a vacuum debinding furnace for thermal debinding to remove the binder completely. The vacuum degree is 3.0 × 10⁻⁶. -3 Pa; Degreasing heating program: First, increase the temperature from room temperature to 100℃ at 5℃ / min, and hold at 100℃ for 0.5h; then increase the temperature from 100℃ to 200℃ at 5℃ / min, and hold at 200℃ for 1h; next, increase the temperature from 200℃ to 300℃ at 3℃ / min, and hold at 300℃ for 1h; then increase the temperature from 300℃ to 420℃ at 2℃ / min, and hold at 420℃ for 1h; finally, increase the temperature from 420℃ to 550℃ at 2℃ / min, and hold at 550℃ for 1h. Finally, cool with the furnace and remove the degreased sample.

[0045] 5) Hot pressing and sintering: The degreased blank is placed into a graphite mold and placed in a medium frequency sintering furnace for hot pressing and sintering. The sintering temperature is 750℃, the sintering pressure is 5MPa, and the holding time is 150s. After the sintering is completed, the sintered sample of an ultra-thin diamond dicing blade with a microporous structure is obtained from the mold.

[0046] 6) Water bath dissolution: The sintered sample was immersed in distilled water at 80℃ for 4 hours, then removed and ultrasonically cleaned at 30kHz for 30 minutes. After rinsing with distilled water and drying, an ultrathin diamond dicing blade with a medium-pore microporous structure was obtained, with a micropore diameter of 110~120μm. Figure 1 As shown, the micropores are discretely distributed on the ultrathin diamond dicing blade substrate.

[0047] Example 2

[0048] Design an ultrathin diamond dicing blade with Al2O3 hollow sphere pore-forming agent, measuring Φ58×0.30×40mm. The diamond concentration is 20 vol%; the Al2O3 hollow sphere pore-forming agent concentration is 10 vol%; the total volume concentration of the binder is 30 vol%, with the remainder being binder. The binder composition is 70 vol% CuSn. 10 The binder consists of 20 wt% Co and 10 wt% WC; the binder components are 54.9 wt% styrene-butadiene block copolymer, 30 wt% polyurethane, 5 wt% polyvinyl formal, 5 wt% acrylonitrile-butadiene-styrene copolymer, 5 wt% phthalate, and 0.1 wt% stearic acid. The diamond particles have a diameter of 20-40 μm, the Al2O3 hollow sphere pore-forming agent particles have a diameter of approximately 10 μm, and the binder powder has a diameter of 100-120 μm.

[0049] This example provides a 3D printing process for an ultrathin diamond dicing blade with a microporous structure, including the following steps:

[0050] 1) Preparation of printing filament: Weigh appropriate amounts of diamond particles, pore-forming agent powder, metal powder and binder, mix them evenly and put them into an internal mixer for thorough mixing. Put the resulting feed into a granulator for granulation, and then put the granules into a wire drawing machine to extrude filaments with a diameter of 1.75mm±0.10mm. The mixing, granulation and wire drawing temperatures are all 250℃ and the rotation speed is 100rpm.

[0051] 2) Printing model and parameter design: Draw the model of the ultrathin diamond dicing blade with the microporous structure in the computer, import the model into the dicing software to set the printing parameters, and then export the printing file; the printing parameters are: nozzle diameter 1mm, printing layer thickness 0.5mm, extrusion rate 50mm / s, flow rate 100%; printing temperature is 200℃.

[0052] 3) Green printing: Import the printing file into the 3D printer, put the filament into the printer feed port, and start the printer to print a green blank of an ultra-thin diamond dicing blade with a microporous structure;

[0053] 4) Green body debinding: The obtained green body is placed into a graphite mold and then placed in a vacuum debinding furnace for thermal debinding to remove the binder completely. The vacuum degree is 3.0 × 10⁻⁶. -3 Pa; Degreasing heating procedure: First, increase the temperature from room temperature to 100℃ at 5℃ / min, and hold at 100℃ for 0.5h; then increase the temperature from 100℃ to 180℃ at 5℃ / min, and hold at 180℃ for 1h; next, increase the temperature from 180℃ to 280℃ at 3℃ / min, and hold at 280℃ for 1h; then increase the temperature from 280℃ to 350℃ at 2℃ / min, and hold at 350℃ for 1h; then increase the temperature from 350℃ to 420℃ at 2℃ / min, and hold at 420℃ for 1h; finally, increase the temperature from 420℃ to 520℃ at 2℃ / min, and hold at 520℃ for 0.5h. Finally, cool with the furnace and remove the degreased sample.

[0054] 5) Hot pressing and sintering: The degreased blank is placed into a graphite mold and placed in a medium frequency sintering furnace for hot pressing and sintering. The sintering temperature is 750℃, the sintering pressure is 5MPa, and the holding time is 120s. After the sintering is completed, the sintered sample of an ultra-thin diamond dicing blade with a microporous structure is obtained from the mold.

[0055] 6) Dressing: The sintered sample was dressed by ultrasonic-assisted micro-grinding. Nanodiamond suspension was used as the grinding fluid. The diamond grinding wheel was dressed on a surface precision grinding machine at a spindle speed of 2800~3500rpm and a feed rate of 5~15mm / min. Then, it was ultrasonically cleaned with anhydrous ethanol + acetone (1:1) mixture for 10 minutes, rinsed with distilled water and dried to obtain an ultrathin diamond dicing blade with a precise pore microporous structure and a micropore diameter of 11.5~12.2μm.

[0056] Example 3

[0057] An ultrathin diamond dicing blade with added NaCl pore-forming agent was designed, with dimensions of Φ58×0.30×40mm. The diamond particle concentration was 20 vol%; the NaCl pore-forming agent concentration was 1 vol%; the total volume concentration of the binder was 30 vol%, with the remainder being binder. The composition of the binder and binder was the same as in Example 1. The diamond particle size was 125~150 μm, the NaCl pore-forming agent powder particle size was approximately 100 μm, and the binder powder particle size was 100~120 μm.

[0058] This example provides a 3D printing process for an ultrathin diamond dicing blade with a microporous structure, including the following steps:

[0059] 1) Preparation of printing filament: Weigh appropriate amounts of diamond powder, pore-forming agent powder, metal powder and binder, mix them evenly and put them into an internal mixer for thorough mixing. Put the resulting feed into a granulator for granulation, and then put the granules into a wire drawing machine to extrude filaments with a diameter of 1.75mm±0.10mm. The mixing, granulation and wire drawing temperatures are all 200℃ and the wire drawing speed is 80rpm.

[0060] 2) Printing model and parameter design: Draw the model of the ultrathin diamond dicing blade with the microporous structure in the computer, import the model into the dicing software to set the printing parameters, and then export the printing file; the printing parameters are: nozzle diameter 1mm, printing layer thickness 0.5mm, extrusion rate 50mm / s, flow rate 100%, and printing temperature 200℃.

[0061] 3) Green printing: Import the printing file into the 3D printer, put the filament into the printer feed port, and start the printer to print a green blank of an ultra-thin diamond dicing blade with a microporous structure;

[0062] 4) Green body debinding: The obtained green body is placed into a graphite mold and then placed in a vacuum debinding furnace for thermal debinding to remove the binder completely. The vacuum degree is 3.0 × 10⁻⁶. -3 Pa; Degreasing heating procedure: First, increase the temperature from room temperature to 100℃ at 5℃ / min, and hold at 100℃ for 0.5h; then increase the temperature from 100℃ to 180℃ at 5℃ / min, and hold at 180℃ for 1h; next, increase the temperature from 180℃ to 280℃ at 3℃ / min, and hold at 280℃ for 1h; then increase the temperature from 280℃ to 350℃ at 2℃ / min, and hold at 350℃ for 1h; then increase the temperature from 350℃ to 420℃ at 2℃ / min, and hold at 420℃ for 1h; finally, increase the temperature from 420℃ to 520℃ at 2℃ / min, and hold at 520℃ for 0.5h. Finally, cool with the furnace and remove the degreased sample.

[0063] 5) Hot pressing and sintering: The degreased blank is placed into a graphite mold and placed in a medium frequency sintering furnace for hot pressing and sintering. The sintering temperature is 750℃, the sintering pressure is 5MPa, and the holding time is 120s. After the sintering is completed, the sintered sample of an ultra-thin diamond dicing blade with a microporous structure is obtained from the mold.

[0064] 6) Water bath dissolution: Soak the sintered sample in distilled water at 80℃ for 4 hours, take it out and put it in an ultrasonic cleaner for 30 minutes at a frequency of 30kHz. After rinsing with distilled water, dry it to obtain an ultrathin diamond scribing blade with a very small amount of medium porosity (micropore diameter of 110~120μm) and a uniformly distributed microporous structure.

[0065] Comparative Example 1

[0066] A 3D printing method was designed to fabricate a metal-based ultrathin diamond dicing blade with dimensions of Φ58×0.30×40mm. This comparative example differs from Example 1 only in that no pore-forming agent was added and no post-treatment was performed to remove the pore-forming agent; all other steps and conditions were identical, resulting in a conventional metal-based ultrathin diamond dicing blade.

[0067] Comparative Example 2

[0068] Metal-based ultrathin diamond dicing blades with dimensions of Φ58×0.30×40mm were prepared by conventional hot pressing sintering. This comparative example used the same formulation as Example 1, and was prepared by hot pressing sintering and water bath dissolution: the raw material powders were mixed and placed in a graphite mold, then placed in a hot pressing sintering furnace for sintering at 750℃, 10MPa, and a holding time of 600s. After sintering, the sintered sample was removed from the mold; it was then immersed in 80℃ distilled water for 4 hours, removed, and subjected to ultrasonic cleaning at 30kHz for 30 minutes. After rinsing with distilled water and drying, the metal-based ultrathin diamond dicing blade prepared by conventional hot pressing sintering was obtained.

[0069] The microporous ultrathin diamond dicing blades fabricated by 3D printing in Examples 1-3 and Comparative Example 1 were tested on a precision dicing machine. Under the same conditions, five silicon wafers were cut from each blade. The average maximum chipping on the front side of the experimental group in Example 1 was 20-28 μm, in Example 2 it was 12-18 μm, and in Comparative Example 1 it was 25-40 μm. Under the same conditions, 1000 μm of glass samples were cut from each blade. The edge wear of the blade in Example 1 was 0.15 mm, in Example 2 it was 0.26 mm, in Example 3 it was 0.06 mm, and in Comparative Example 1 it was 0.09 mm.

[0070] Measurements of the microporous ultrathin diamond dicing blade prepared by hot-pressing sintering in Comparative Example 2 revealed that the dicing thickness ranged from 0.27 to 0.38 mm, exhibiting inconsistent thickness and uneven distribution of micropores on the surface. The dicing blade from Comparative Example 2 was tested on a precision dicing machine, cutting five silicon wafers under identical conditions. The maximum chipping on the front side of the Comparative Example 2 experimental group exceeded 200 μm, and the dicing thickness and dicing groove width were uneven, failing to meet usage requirements. The edge wear of the dicing blade in Comparative Example 2 was 0.23 mm, and no visible micropores were observed in the dicing cross-section.

[0071] The ultrathin diamond dicing blades obtained in Example 1 and Comparative Example 1 were subjected to long-distance (5000 meters) dicing tests on silicon wafers on a precision dicing machine. After the dicing test, there were no obvious defects on the surface of Example 1, while cracks appeared on the dicing surface of Comparative Example 1 and the dicing blade broke. The comprehensive test results showed that the self-sharpening property of Example 1 was improved by 20-30% compared with Comparative Example 1, the cutting efficiency was improved by 15-43%, and the service life was extended by 8-30%.

Claims

1. A method for preparing an ultrathin diamond dicing blade with a microporous structure, characterized in that: Diamond particles, binder, adhesive, and pore-forming agent with a particle size of micrometers are prepared and mixed to obtain a mixture; the mixture is then subjected to intensive mixing, granulation, and filament forming to obtain dicing filaments; the dicing filaments are then placed in a 3D printer for 3D printing to obtain a green body; the green body is then degreased and sintered to obtain a sintered sample. The sintered sample is then post-treated to remove the pore-forming agent, and the sintered sample is obtained. The pore-forming agent includes inorganic salt pore-forming agents or hollow microsphere pore-forming agents; The micropores in the ultrathin diamond dicing blade with microporous structure are discretely distributed on the ultrathin diamond dicing blade substrate.

2. The method for preparing an ultrathin diamond dicing blade with a microporous structure according to claim 1, characterized in that: When the pore-forming agent is an inorganic salt pore-forming agent, the post-treatment uses water bath dissolution to remove the pore-forming agent; when the pore-forming agent is a hollow microsphere pore-forming agent, the post-treatment uses at least one of grinding dressing, electrical discharge dressing, laser polishing dressing, and ultrasonic-assisted micro-grinding dressing to remove the pore-forming agent.

3. The method for preparing an ultrathin diamond dicing blade with a microporous structure according to claim 2, characterized in that: The inorganic salt pore-forming agent includes at least one of NaCl and KCl, with a particle size of 0.1 μm to 500 μm; the hollow microsphere pore-forming agent includes at least one of Al2O3 hollow spheres and glass hollow spheres, with a particle size of 0.1 μm to 200 μm.

4. The method for preparing an ultrathin diamond dicing blade with a microporous structure according to claim 2, characterized in that: The specific process of water bath dissolution is as follows: the sintered sample is soaked in distilled water at 60~80℃ for 2~8 hours, then ultrasonically cleaned for 20~60 minutes at 20~50kHz, rinsed with distilled water and dried.

5. A method for preparing an ultrathin diamond dicing blade with a microporous structure according to any one of claims 1 to 4, characterized in that: The mixture comprises the following components by volume fraction: 30-60% binder, 0.5-25% pore-forming agent, 5-35% diamond particles, and the balance being binder; The adhesive, by weight, comprises the following components: 30-75 parts of styrene-butadiene block copolymer, 5-35 parts of polyurethane, 5-10 parts of polyvinyl alcohol formaldehyde, 3-6 parts of acrylonitrile-butadiene-styrene copolymer, 3-6 parts of phthalate, and 0.1-0.4 parts of stearic acid.

6. The method for preparing an ultrathin diamond dicing blade with a microporous structure according to claim 5, characterized in that: The binder, by mass fraction, comprises: 40%~100% copper-tin alloy, with the balance being M; wherein M is selected from at least one of tungsten carbide, cobalt, iron, nickel, titanium, chromium, zinc, and boron; The diamond particles have a diameter of 1~450μm, and the binder has a diameter of ≤450μm.

7. The method for preparing an ultrathin diamond dicing blade with a microporous structure according to claim 1, characterized in that: The mixing, granulation, and drawing processes are all carried out at temperatures of 100~300°C and rotation speeds of 10~200 rpm, in order to control the diameter of the dicing blade wire to be 1.65~1.85 mm. The 3D printing process parameters are: printing layer thickness 0.01mm~0.5mm, extrusion rate 10~300mm / s, and printing temperature 100~300℃; The sintering conditions are: temperature of 650~900℃, and sintering pressure of 50~200 kg / cm². 2 The heat preservation and pressure holding time is 120~600s.

8. An ultrathin diamond dicing blade with a microporous structure, characterized in that: It is obtained by the preparation method according to any one of claims 1 to 7.

9. The ultrathin diamond dicing blade with a microporous structure according to claim 8, characterized in that: The pore size of the micropores in the microporous structure is 1.2 times the particle size of the pore-forming agent; and the thickness of the diamond dicing blade is ≤2mm.

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