Diamond grinding disc and preparation method thereof

Abstract

The invention provides a diamond grinding disc. The grinding disc is mainly prepared from the following raw materials in percentage by weight: 15 to 45 weight percent of copper, 9 to 25 weight percent of tin, 3 to 8 weight percent of iron, 1 to 5 weight percent of vanadium, 3 to 12 weight percent of sodium aluminosilicate, 2 to 10 weight percent of phenolic resin liquid and 25 to 45 weight percent of diamond. The preparation method comprises the following steps: material mixing: mixing and grinding the components except the phenolic resin liquid, and sieving to obtain a forming material; sintering and molding: carrying out heat preservation on the molded material in a muffle furnace, pressurizing and maintaining the pressure on a hot press, and unloading the mold to obtain a grinding disc blank; the surface of the grinding disc is subjected to sand blasting treatment, and then the grinding disc is put into a container containing phenolic resin liquid for ultrasonic treatment; and then carrying out post-curing treatment and turning, milling and grinding to obtain the product. The grinding disc is applied to grinding hard and brittle materials such as natural / artificial diamonds, metal ceramics, functional ceramics and semiconductor materials, and can meet the requirement for efficient machining in the industry.

Description

Technical Field

[0001] This invention belongs to the field of polishing disc technology, specifically relating to a diamond polishing disc and its preparation method. Background Technology

[0002] Diamond grinding wheels are the primary tools for grinding hard and brittle materials such as cermets, functional ceramics, synthetic diamonds, and semiconductors. Grinding is the main method for grinding hard and brittle materials, especially sheet-like materials. During the grinding process, the diamond abrasive on the grinding wheel is brought into contact with the workpiece surface through online dressing. Then, axial pressure is applied to make contact with the workpiece surface. Under the lubrication of the grinding fluid, the grinding wheel performs a scraping and plowing motion on the workpiece surface through its own rotation and the workpiece's rotation and revolution. During this process, the material on the workpiece surface is removed.

[0003] With technological advancements, the hardness, purity, and aspect ratio of flake-shaped hard and brittle materials have increased, making their grinding and processing more challenging. Traditional diamond grinding discs exhibit a series of problems when grinding hard and brittle flake materials in the context of emerging technologies, including difficulty in grinding, inability to remove material, abnormal noise, grinding machine vibration, chipping, breakage, deep scratches, and large thickness deviations. These issues severely impact production efficiency and hinder the further development of new material technologies.

[0004] Therefore, in order to overcome the above-mentioned application problems of diamond grinding discs for processing hard and brittle materials, this invention has made technical innovations and provides a diamond grinding disc and its preparation method. The prepared diamond grinding disc can meet the industry's demand for high-efficiency processing. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a diamond grinding disc. This grinding disc is used for grinding hard and brittle materials such as natural / synthetic diamonds, cermets, functional ceramics, and semiconductor materials, and can meet the industry's demand for high-efficiency processing.

[0006] The present invention also provides a method for preparing the above-mentioned diamond grinding disc.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A diamond grinding disc, wherein the grinding disc is mainly made of the following raw materials in weight percentage: 15-45wt% copper, 9-25wt% tin, 3-8wt% iron, 1-5wt% vanadium, 3-12wt% sodium aluminosilicate, 2-10wt% phenolic resin liquid, and 25-45wt% diamond; wherein the vanadium in the components can synergistically act with other metals during the sintering process, on the one hand improving the wear resistance of the grinding disc, and on the other hand promoting the uniformity of the structure.

[0008] Specifically, the components of the grinding disc, including copper, tin, iron, vanadium, and sodium aluminosilicate, are all micronized powders. The Malvern particle size (D50) of the copper, tin, iron, and vanadium is 8-15 micrometers. The Malvern particle size (D50) of the sodium aluminosilicate is 10-25 micrometers.

[0009] Furthermore, in the components of the grinding disc, the initial state of the phenolic resin is liquid (i.e., phenolic resin liquid), and the viscosity at room temperature is 8-18 cP.

[0010] This invention provides a method for preparing the above-mentioned diamond grinding disc, wherein the grinding disc is pressed using a fixed mold, and includes the following steps: 1) Mixing: Mix and grind the raw materials copper, tin, iron, vanadium, sodium aluminosilicate and diamond, then sieve them. Add an appropriate amount of polyethylene glycol liquid, stir, dry, grind and sieve again to obtain the molding material. 2) Sintering and molding: The molding material is placed into the assembled mold cavity, the pressure plate is covered, and it is held in a muffle furnace at 400-800℃ for 1-4 hours. After removing the mold, it is pressed and held on a hot press at a pressure of 0.15-0.25 KN / mm. 2 (Holding time 20-50 min), demold to obtain grinding disc blank; 3) Resin liquid impregnation: The surface of the grinding disc blank is sandblasted, and then the grinding disc blank is placed in a container filled with phenolic resin liquid and ultrasonicated for 20-60 minutes. Then it is taken out and set aside for use. 4) Post-curing treatment: The grinding disc obtained in step 3) undergoes post-curing treatment and milling and grinding to obtain the finished grinding disc.

[0011] Specifically, in step 1), the amount of polyethylene glycol liquid added is 2-10 wt% of the sum of the masses of the raw materials copper, tin, iron, vanadium, sodium aluminosilicate, and diamond. During the preparation of the grinding disc, a temporary molding agent, polyethylene glycol, is needed. Its function is to improve the adhesion of the molding material, giving the raw material blank a certain strength after pressing, making it less prone to loosening. During the subsequent sintering process, as the temperature rises, the polyethylene glycol in the grinding disc will gradually be removed, leaving pores in the grinding disc, which is the main source of porosity in porous grinding discs.

[0012] Furthermore, in step 4), the post-curing treatment is to dry in a drying oven at 100-300℃ for 10-12 hours.

[0013] The present invention also provides the application of the above-mentioned diamond grinding disc in grinding hard and brittle materials such as natural diamond, synthetic diamond, cermet, functional ceramics, or semiconductor materials.

[0014] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows: In this invention, copper, tin, and iron are the main components of the diamond grinding disc binder, forming the metal skeleton of the binder. The alloy phase formed by these three components during sintering effectively improves the wear resistance of the grinding disc. Sodium aluminosilicate, a brittle ceramic phase, is a functional filler for the diamond grinding disc. In the binder, it reduces the bending strength of the grinding disc, increases its self-sharpening ability, and enhances its sharpness. Simultaneously, it acts as a lubricant during grinding, improving the surface finish of the workpiece. Phenolic resin, during the preparation of the grinding disc, fills the pores in the binder by occupying and solidifying, and combines with other components in the grinding disc. The main function of the thermosetting phenolic resin is to improve the sharpness of the grinding disc. Simultaneously, during grinding, the phenolic resin on the grinding surface provides a buffering effect between the grinding disc and the workpiece, absorbing grinding vibrations, buffering grinding pressure, reducing the depth of the damage layer on the workpiece surface, and improving grinding quality. The grinding disc of this invention is used for grinding hard and brittle materials such as natural diamond, synthetic diamond, cermet, functional ceramics, and semiconductor materials. It has the advantages of large feed rate, high grinding efficiency, good flatness, no chipping or serrations on the cutting edge, and high grinding quality, which can meet the needs of high-efficiency processing in the industry. Attached Figure Description

[0015] Figure 1 The image shows the diamond grinding disc of the present invention (left) and a partial enlarged view (right); it can be seen from the image that the surface of the grinding disc has high porosity, uniform pore size, and no obvious agglomeration phenomenon on the surface of the grinding disc. Detailed Implementation

[0016] The technical solution of the present invention will be further described in detail below with reference to the embodiments, but the scope of protection of the present invention is not limited thereto.

[0017] In the following embodiments, the raw materials used are all commercially available products that can be purchased directly, or can be prepared using conventional methods in the art; the processes not described in detail can be carried out using conventional techniques in the art, and since they are not the innovation of this application, they will not be described in detail here.

[0018] In the examples, the phenolic resin liquid used had a viscosity of 8-18 cP at room temperature; the polyethylene glycol liquid used had an average molecular weight of 800; both were commercially available products.

[0019] Room temperature refers to 25±5℃.

[0020] Example 1 A diamond grinding disc is mainly made of the following raw materials in weight percentages: 20wt% copper, 20wt% tin, 7wt% iron, 3wt% vanadium, 10wt% sodium aluminosilicate, 5wt% phenolic resin liquid, and 35wt% diamond; the Malvern particle size D50 of copper, tin, iron, and vanadium is 9 micrometers, and the Malvern particle size D50 of sodium aluminosilicate is 15 micrometers.

[0021] The above-mentioned method for preparing diamond grinding discs includes the following steps: 1) Mixing: Mix and grind the raw materials copper, tin, iron, vanadium, sodium aluminosilicate and diamond, and pass them through a 150# standard sieve 5 times. Add an appropriate amount of polyethylene glycol liquid (the amount of polyethylene glycol liquid added is 3wt% of the sum of the mass of raw materials copper, tin, iron, vanadium, sodium aluminosilicate and diamond), stir, dry at 90℃ for 30 minutes, take out the powder, grind it with a mortar and pestle, and pass it through an 80# standard sieve 5 times to obtain the molding material; 2) Sintering and molding: The molding material is placed into the assembled mold cavity, the powder is leveled with a scraper, the pressure plate is placed on top, and the mold is held at 400℃ for 1.5 hours in a muffle furnace. The mold is then removed and pressed on a hot press (pressing pressure 0.21KN / mm). 2 Hold pressure for 30 minutes, then remove from mold to obtain grinding disc blank; 3) Resin liquid impregnation: The surface of the grinding disc blank is sandblasted with brown corundum sand, and then the grinding disc blank is placed in a container filled with phenolic resin liquid. The container is placed in an ultrasonic bath for 60 minutes at room temperature. The grinding disc is then removed and set aside for use. 4) Post-curing treatment: Place the grinding disc that has adsorbed the phenolic resin liquid into a drying oven and perform post-curing treatment at 150℃ for 8.5 hours; 5) Finished product: The post-curing grinding disc is machined by turning and milling to obtain the finished grinding disc.

[0022] Example 2 A diamond grinding disc and its preparation method are disclosed. The grinding disc is mainly made of the following raw materials in weight percentage: 36wt% copper, 10wt% tin, 6wt% iron, 3wt% vanadium, 4wt% sodium aluminosilicate, 8wt% phenolic resin liquid, and 33wt% diamond. The Malvern particle size D50 of copper, tin, iron, and vanadium is 12 micrometers, and the Malvern particle size D50 of sodium aluminosilicate is 18 micrometers.

[0023] The above-mentioned method for preparing diamond grinding discs includes the following steps: 1) Mixing: Mix and grind the raw materials copper, tin, iron, vanadium, sodium aluminosilicate and diamond, and pass them through a 150# standard sieve 3 times. Add an appropriate amount of polyethylene glycol liquid (the amount of polyethylene glycol liquid added is 8wt% of the sum of the mass of raw materials copper, tin, iron, vanadium, sodium aluminosilicate and diamond), stir, dry at 60℃ for 40 minutes, take out the powder, grind it with a mortar and pestle, and pass it through an 80# standard sieve 3 times to obtain the molding material; 2) Sintering and molding: The molding material is placed into the assembled mold cavity, the powder is leveled with a scraper, the pressure plate is placed on top, and the mold is held at 750℃ for 3.5 hours in a muffle furnace. The mold is then removed and pressed on a hot press (pressing pressure 0.21KN / mm). 2Hold pressure for 41 minutes, then remove from mold to obtain grinding disc blank; 3) Resin liquid impregnation: The surface of the grinding disc is sandblasted with brown corundum sand. Then, the grinding disc blank is placed in a container filled with phenolic resin liquid. The container is placed in an ultrasonic bath and ultrasonically sonicated at room temperature for 20 minutes. The grinding disc is then removed and set aside for use. 4) Post-curing treatment: Place the grinding disc that has adsorbed the phenolic resin liquid into a drying oven and perform post-curing treatment at 300℃ for 12 hours; 5) Finished product processing: The post-cured grinding disc is then machined by turning and milling to obtain the finished grinding disc (see...). Figure 1 ).

[0024] Example 3 A diamond grinding disc and its preparation method are disclosed. The grinding disc is mainly made of the following raw materials in weight percentages: 32wt% copper, 15wt% tin, 5wt% iron, 2wt% vanadium, 8wt% sodium aluminosilicate, 8wt% phenolic resin liquid, and 30wt% diamond. The Malvern particle size D50 of copper, tin, iron, and vanadium is 15 micrometers, and the Malvern particle size D50 of sodium aluminosilicate is 12 micrometers.

[0025] The above-mentioned method for preparing diamond grinding discs includes the following steps: 1) Mixing: Mix and grind the raw materials copper, tin, iron, vanadium, sodium aluminosilicate and diamond, and pass them through a 150# standard sieve 4 times. Add an appropriate amount of polyethylene glycol liquid (the amount of polyethylene glycol liquid added is 5wt% of the sum of the mass of raw materials copper, tin, iron, vanadium, sodium aluminosilicate and diamond), stir, dry at 60℃ for 20 minutes, take out the powder, grind it with a mortar and pestle, and pass it through an 80# standard sieve 4 times to obtain the molding material; 2) Sintering and molding: The molding material is placed into the assembled mold cavity, the powder is leveled with a scraper, the pressure plate is placed on top, and the mold is held at 650℃ for 2 hours in a muffle furnace. The mold is then removed and pressed on a hot press (pressing pressure 0.21KN / mm). 2 Hold pressure for 25 minutes, then remove from mold to obtain grinding disc blank; 3) Resin liquid impregnation: The surface of the grinding disc is sandblasted with brown corundum sand. Then, the grinding disc blank is placed in a container filled with phenolic resin liquid. The container is placed in an ultrasonic bath and ultrasonically sonicated at room temperature for 30 minutes. The grinding disc is then removed and set aside for use. 4) Post-curing treatment: Place the grinding disc that has adsorbed the phenolic resin liquid into a drying oven and perform post-curing treatment at 250℃ for 10 hours; 5) Finished product: The post-curing grinding disc is machined by turning and milling to obtain the finished grinding disc.

[0026] Comparative Example 1 Purchase commercially available grinding discs for grinding synthetic diamonds, 600mm in diameter, 320# grit.

[0027] Comparative Example 2 Purchase commercially available grinding discs for grinding metal-ceramic cutting tools, 600mm in diameter, 800# grit.

[0028] Grinding test The grinding discs prepared in the above examples and comparative examples were used to grind 10mm×10mm CVD diamond square pieces on a double-end grinding machine. The feed rate, flatness and grinding quality were recorded and the results are summarized in Table 1.

[0029] Table 1 Results of grinding CND diamonds with two different grinding discs As can be seen from the results in Table 1 above, compared with Comparative Example 1, when grinding CVD diamond using the diamond grinding disc of the present invention, the feed rate is larger, the grinding efficiency is higher, the flatness is better, and there is no chipping on the cutting edge, resulting in higher grinding quality.

[0030] The grinding discs prepared in the above examples and comparative examples were used to grind the indexable metal ceramic inserts of model TNGG160402R on a grinding machine. The single feed rate, flatness and chipping of the cutting edge were recorded, and the results were summarized in Table 2.

[0031] Table 2 Results of grinding cermet tools with two different grinding discs As can be seen from the results in Table 2 above, compared with Comparative Example 2, when grinding metal ceramic cutting tools using the diamond grinding disc of the present invention, it can meet the requirements of large depth of cut and fast feed grinding, the surface flatness of the ground cutting tool is better, and the cutting edge is free of serrations, resulting in higher grinding quality.

Claims

1. A diamond grinding disc, characterized in that, The grinding disc is mainly made of the following raw materials by weight percentage: copper 15-45wt%, tin 9-25wt%, iron 3-8wt%, vanadium 1-5wt%, sodium aluminosilicate 3-12wt%, phenolic resin liquid 2-10wt%, and diamond 25-45wt%.

2. The diamond grinding disc as described in claim 1, characterized in that, The Malvern particle size D50 of the copper, tin, iron, and vanadium is 8-15 micrometers.

3. The diamond grinding disc as described in claim 1, characterized in that, The sodium aluminosilicate has a Malvern particle size (D50) of 10-25 micrometers.

4. The diamond grinding disc as described in claim 1, characterized in that, The phenolic resin liquid has a room temperature viscosity of 8-18 cP.

5. The method for preparing the diamond grinding disc according to any one of claims 1 to 4, characterized in that, Includes the following steps: 1) Mixing: Mix and grind the raw materials copper, tin, iron, vanadium, sodium aluminosilicate and diamond, then sieve them. Add an appropriate amount of polyethylene glycol liquid, stir, dry, grind and sieve again to obtain the molding material. 2) Sintering and molding: The molding material is kept at 400-800℃ for 1-4 hours, and then pressed and held on a hot press to obtain the grinding disc blank; 3) Resin liquid impregnation: The surface of the grinding disc blank is sandblasted, and then the grinding disc blank is placed in a container filled with phenolic resin liquid and ultrasonicated for 20-60 minutes. Then it is taken out and set aside for use. 4) Post-curing treatment: The grinding disc obtained in step 3) undergoes post-curing treatment and milling and grinding to obtain the finished grinding disc.

6. The method for preparing the diamond grinding disc according to claim 5, characterized in that, In step 1), the amount of polyethylene glycol liquid added is 2-10 wt% of the sum of the mass of the raw materials copper, tin, iron, vanadium, sodium aluminosilicate, and diamond.

7. The method for preparing the diamond grinding disc according to claim 5, characterized in that, In step 4), the post-curing treatment is to dry in a drying oven at 100-300℃ for 10-12 hours.

8. The use of the diamond grinding disc according to any one of claims 1 to 4 in grinding natural diamond, synthetic diamond, cermet, functional ceramic, or semiconductor materials.

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