Epoxy resin binder diamond Brad grinding block and production process thereof

Abstract

The invention relates to the field of diamond Brad grinding tools, and particularly discloses an epoxy resin binder diamond Brad grinding block and a production process thereof. The epoxy resin binder diamond Brad grinding block comprises the following raw materials in percentage by weight: 20-30% of liquid epoxy resin, 5-15% of powder epoxy resin, 5-10% of a diamond grinding material, 10-15% of a curing agent, 5-10% of an auxiliary grinding material, 25-40% of a filler, 0.2-0.8% of a defoaming agent and 1-3% of a diluent. The epoxy value of the liquid epoxy resin is 0.48 to 0.54; the epoxy value of the powder epoxy resin is 0.22 to 0.26. According to the diamond Brad grinding block, flexible adjustment of the performance can be completed by changing the using amount of the liquid epoxy resin and the powder epoxy resin according to different machining objects and customer requirements, and the diamond Brad grinding block has the advantages of being high in universality, good in abrasion resistance and grinding and polishing effect, high in luminosity and the like.

Description

Technical Field

[0001] The present application relates to the technical field of diamond abrasive belts, and more specifically, to an epoxy resin bonded diamond abrasive belt block and its production process. Background Art

[0002] Traditional abrasive blocks used for grinding and polishing in automatic production lines for stones such as marble and granite are made with magnesite mainly composed of magnesium oxide and magnesium chloride as the binder, and silicon carbide abrasive grains added. Its characteristic is that the sharpness is okay, but the service life is very short. The grinding and polishing line needs to frequently stop to change the abrasive block, and the operating labor intensity is high. Therefore, diamond resin abrasive belt blocks made with resin as the binder and diamond as the abrasive grains have emerged. Such diamond abrasive belt blocks have remarkable characteristics such as good sharpness, strong grinding force, high grinding efficiency, good wear resistance, and can withstand large loads, and can meet the requirements of high-speed grinding and precision grinding technologies.

[0003] In the prior art, the Chinese invention patent application document with the application number CN201510571213.4 discloses a material for a phenolic resin diamond grinding tool for preparing ceramic polished tiles, which is prepared from the following raw materials in a mass ratio: 35 - 48 parts of phenolic resin, 2 - 5 parts of powdered nitrile rubber, 10 - 16 parts of diamond, 0 - 33 parts of silicon carbide, 5 - 28 parts of zinc oxide, and 3 - 7 parts of white carbon black.

[0004] In view of the above related technologies, the inventor found that for high-temperature-resistant abrasives such as diamond and cubic boron nitride, due to the high hardness and poor toughness of phenolic resin, the holding force for the abrasives is relatively low, and it is prone to oxidation and even degradation when the temperature exceeds 200°C. During the grinding process, some abrasives will fall off and break due to the decomposition of phenolic resin before being completely dull, seriously affecting the grinding efficiency and service life of the grinding tool. Especially with the increasing demand for high-grade granite veneers, luxury stones, and natural quartz stones, the grinding and polishing requirements are getting higher and higher, and the grinding and polishing difficulty is increasing continuously. The abrasive belt blocks using phenolic resin as the binder have been difficult to meet the use requirements, and the liquid abrasive belt blocks using epoxy resin as the binder are gradually being developed by the market. Summary of the Invention

[0005] In order to enhance the grinding and polishing effect of the diamond abrasive belt block and make it have better versatility, the present application provides an epoxy resin bonded diamond abrasive belt block and its production process.

[0006] In the first aspect, the present application provides an epoxy resin bonded diamond abrasive belt block, adopting the following technical scheme: An epoxy resin binder diamond grinding block, comprising raw materials in the following weight percentages: 20-30% of liquid epoxy resin, 5-15% of powdered epoxy resin, 5-10% of diamond abrasive, 10-15% of curing agent, 5-10% of auxiliary abrasive, 25-40% of filler, 0.2-0.8% of defoaming agent, and 1-3% of diluent; The epoxy value of the liquid epoxy resin is 0.48-0.54; The epoxy value of the powdered epoxy resin is 0.22-0.26.

[0007] By adopting the above technical solution, the cooperation of liquid epoxy resin with a higher epoxy value and powdered epoxy resin with a lower epoxy value plays a certain role in improving the wear resistance, diamond holding force and other properties of the diamond grinding block; when the liquid epoxy resin with a higher epoxy value cures, the crosslinking density is higher, forming a denser network structure, making the product have good strength and heat resistance, which helps to enhance the mechanical wrapping force on diamond particles, and at the same time resist wear and impact during the grinding process. Moreover, the liquid epoxy resin has strong adhesiveness and good fluidity, can fully infiltrate the surface of diamond particles, form a good interfacial bonding force, helps to reduce particle shedding during the grinding process, and maintain the long-term wear resistance of the grinding block; while the powdered epoxy resin with a lower epoxy value has a longer molecular chain, can provide better toughness, increase the solid content of the system, reduce the shrinkage rate, and improve the volume stability. At the same time, the particles of the powdered epoxy resin help to form a microscopic mechanical interlocking structure in the resin matrix, further enhancing the energy dissipation efficiency of the resin matrix and improving the impact resistance and wear resistance of the product; therefore, the combination of the two can take into account the crosslinking degree and filling property of the resin matrix, form a matrix structure that is both dense and has a certain hardness, helps to optimize the holding force of the resin on diamond particles, makes the diamond particles not easy to fall off during the grinding process, improves the processing accuracy and service life of the grinding block, and by adjusting the dosage of the liquid epoxy resin and the powdered epoxy resin, the hardness and toughness of the product can be flexibly adjusted, so that the grinding block can adapt to the grinding of different types of stones. In addition, adding filler and auxiliary abrasive can further optimize the product performance to meet the needs of customers.

[0008] Optionally, the mass ratio of the liquid epoxy resin to the powdered epoxy resin is 3.6-6:1.

[0009] By adopting the above technical solution, using a specific dosage ratio of liquid epoxy resin and powdered epoxy resin can obtain appropriate adhesiveness, improve the holding force of the grinding block on diamond particles, and also obtain sufficient flexibility, improve the processability of the grinding block, make it easier to process and form, and can also improve the wear resistance and service life of the grinding block.

[0010] Optionally, the liquid epoxy resin is E51 epoxy resin; the powdered epoxy resin is 0781H type epoxy resin.

[0011] By adopting the above technical solution, the epoxy value of the E51 type liquid epoxy resin is relatively high, and after curing, it has a high crosslinking density, endowing the grinding block with excellent strength and heat resistance. At the same time, its curing speed is fast, which can shorten the processing cycle, and it has good fluidity, facilitating the infiltration of diamond particles, significantly enhancing the holding force of diamond, while the particle morphology of the 0781H type powdered epoxy resin can enhance the micro-mechanical interlocking effect of the resin matrix. The combination of the two can improve the energy dissipation efficiency of the resin matrix, reduce the particle shedding during the grinding collision, and improve the performance stability of the grinding block under different processing environments.

[0012] Optionally, the filler is selected from at least one of alumina, zinc oxide, calcium carbonate, talcum powder, titanium dioxide, cryolite, silicon dioxide powder, and polypropylene powder.

[0013] By adopting the above technical solution, powders such as zinc oxide and alumina as fillers can enhance the cutting ability and anti-wear performance of the grinding block, refine the grain structure of the resin matrix, reduce the internal stress during the curing process, lower the risk of grinding block cracking, and at the same time improve the impact resistance performance, avoiding the grinding block from cracking under heavy load conditions. The addition of the filler can also increase the viscosity of the resin system, improve the mixing uniformity, facilitate the molding process, reduce the volume shrinkage during resin curing, lower the risk of grinding block deformation, and in addition, reduce costs, improve heat dissipation, lower the coefficient of thermal expansion, and reduce the cracking of the grinding block caused by thermal stress.

[0014] Optionally, the total proportion of the liquid epoxy resin and the powdered epoxy resin is 35 - 40%.

[0015] By adopting the above technical solution, further optimizing the proportion of the epoxy resin system can not only ensure the firm holding of diamond particles but also avoid the low hardness or poor self-sharpening of the grinding block caused by excessive resin.

[0016] Optionally, the filler contains alumina, zinc oxide, cryolite, and polypropylene powder with a mass ratio of 10:10:6:5.

[0017] By adopting the above technical solution, using alumina, zinc oxide, cryolite, and polypropylene powder as fillers, among which polypropylene powder is a thermoplastic plastic with good flexibility and impact resistance, which can reduce the brittleness of the grinding block after curing, prevent the grinding block from cracking under high-speed rotation or impact load, and can also absorb part of the vibration and improve the grinding stability. Cryolite can absorb the heat generated during the stone grinding process and improve the thermal stability of the matrix. The combination of the two can greatly improve the wear resistance of the product.

[0018] Optionally, the filler contains alumina, calcium carbonate, talcum powder, and titanium dioxide with a mass ratio of 10:6.5:5:5.

[0019] By adopting the above technical solution, alumina, calcium carbonate, talc powder and titanium dioxide are compounded as fillers. Alumina can act as a secondary abrasive to share the wear pressure of diamond, while calcium carbonate can reduce costs and increase the strength of the matrix skeleton. Talc powder has a low hardness, which can reduce frictional loss, and the layered structure of talc powder can absorb stress, prevent crack propagation and avoid scratches on the stone. Titanium dioxide can improve the dispersibility and stability of fillers in the slurry, enhance the uniformity and hardness of the matrix, and improve the polishing effect of the stone. Therefore, the combination of titanium dioxide and talc powder can improve the surface gloss.

[0020] Optionally, the curing agent is at least one of aliphatic polyamines, aromatic polyamines, tertiary amine curing agents, imidazole curing agents, and anhydride curing agents.

[0021] By adopting the above technical solution, the selected curing agents are all medium-high temperature curing agents, which have a long operation time at room temperature, can effectively improve production efficiency, and the produced products have good heat resistance and mechanical strength.

[0022] Optionally, the particle size of the filler is 3000 - 5000 mesh.

[0023] By adopting the above technical solution, the filler within this particle size range can be evenly dispersed in the resin matrix, forming a dense microstructure, reducing surface scratches and roughness, improving the surface finish of the grinding block, refining the grain structure, reducing stress concentration points, and improving the impact resistance, hardness and wear resistance of the grinding block.

[0024] Optionally, the auxiliary abrasive is selected from at least one of white fused alumina, chrome corundum, and silicon carbide micropowder, and the particle size is 120 - 8000 mesh.

[0025] By adopting the above technical solution, the auxiliary abrasive can improve the grinding efficiency, improve the surface quality, enhance the heat dissipation performance, and the addition of the auxiliary abrasive can disperse the stress during the grinding process, reduce the risk of cracking or deformation of the grinding block. During the curing process, it can reduce the shrinkage of the resin matrix and improve the dimensional accuracy of the grinding block.

[0026] Optionally, the auxiliary abrasive includes silicon carbide micropowder and white fused alumina with a mass ratio of 5:4.

[0027] By adopting the above technical solution, silicon carbide micropowder and white fused alumina with a specific mass ratio are used as auxiliary abrasives. The silicon carbide micropowder has a large Mohs hardness, can quickly cut into the stone surface, improve the grinding efficiency, and is easy to break during grinding to form new cutting edges, maintaining continuous sharpness. It can also reduce the temperature of the grinding block and the stone, reducing the risk of thermal damage. The Mohs hardness of white fused alumina is lower than that of silicon carbide and diamond, but it has high toughness and strong anti-breakage ability, suitable for high-load grinding, reducing abrasive shedding, and prolonging the life of the grinding block. Moreover, the toughness of white fused alumina can compensate for the brittleness of silicon carbide, and the cutting force of silicon carbide can make up for the insufficient efficiency of white fused alumina. When used in combination, high-efficiency grinding can be achieved.

[0028] Optionally, the defoaming agent is an organosilicon defoaming agent or an epoxy resin defoaming agent; The diluent is butyl glycidyl ether or alkylene glycidyl ether.

[0029] Optionally, the diamond abrasive is diamond particles with indium-doped zinc oxide deposited on the surface.

[0030] By adopting the above technical solution, indium and zinc oxide are deposited on diamond particles by chemical vapor deposition. It can change the surface polarity of diamond, improve the wettability with epoxy resin, and promote uniform dispersion. Moreover, the nanostructure of indium-doped zinc oxide can also increase the surface roughness of diamond particles, provide physical anchor points, enhance the mechanical bonding with fillers, auxiliary abrasives, etc., increase the holding force of epoxy resin on diamond particles. In addition, indium-doped zinc oxide has good thermal stability and mechanical stability, deposits on the surface of diamond particles to form a protective layer, reduces oxidation or thermal damage at high temperatures, improves heat resistance. At the same time, indium-doped zinc oxide can also act as a lubricant, reduce diamond wear, and improve the wear resistance of the grinding block.

[0031] In the second aspect, the present application provides a production process for an epoxy resin-bonded diamond cloth grinding block, adopting the following technical solution: A production process for an epoxy resin-bonded diamond cloth grinding block includes the following steps: Mix the diamond abrasive with the auxiliary abrasive, filler, liquid epoxy resin, powder epoxy resin, curing agent, defoaming agent, and diluent evenly to obtain a slurry; Inject the slurry into a mold, cover the slurry with a nylon base cloth, and perform mold pressing at 800 - 900 kN for 20 - 30 minutes, and bond it to the bottom plate to obtain an epoxy resin-bonded diamond cloth grinding block.

[0032] By adopting the above technical solution, using liquid epoxy resin and powder epoxy resin as crosslinking and curing resins and combining with the hot pressing method for curing, the abrasive and other auxiliary materials can be well organically combined and fixed, the synergistic effect among the raw materials is fully reflected, the mechanical properties of the grinding block are increased, the wear resistance of the grinding block is greatly improved, and the service life is further improved.

[0033] Optionally, the mold includes a base (1) and a mold cover (2). A mold core (11) for injecting slurry is provided on the base (1), and a cover plate (21) that cooperates with the mold core (11) is connected to the mold cover (2); positioning holes (12) are provided on the base (1), and positioning columns (22) that cooperate with the positioning holes (12) are connected to the mold cover (2).

[0034] By adopting the above technical solution, when the mold in this application prepares the grinding block, no tooling is required for demolding after pressing, and during the curing process of the epoxy resin, basically no gas is generated. Therefore, there is no need to add an exhaust section, which reduces the operation difficulty and increases the product stability.

[0035] In summary, this application has the following beneficial effects: 1. The binder used in the abrasive block of this application is epoxy resin. Compared with the traditional powder phenolic resin binder, it has the advantages of stronger diamond holding force and better matrix toughness. Therefore, it shows higher gloss and better grinding and polishing effects in the processing of stone materials, and better meets the increasingly high-standard processing requirements of customers.

[0036] 2. Since this application uses liquid epoxy resin with a higher epoxy value and powder epoxy resin with a lower epoxy value as the resin matrix, by adjusting the ratio of the two, the hardness, toughness and wear resistance of the grinding block can be flexibly adjusted, enabling the grinding block to have the ability to handle different stone materials and meet different customer needs.

[0037] 3. The method of this application, by adopting a special mold, has a short pressing time, less dust during production, simple demolding, high production efficiency, and a simple process. There is no need for exhaust, and the product performance is more stable. Description of the Drawings

[0038] Figure 1 It is the top view of the base in Embodiment 1 of this application.

[0039] Figure 2 It is the cross-sectional view of the base in Embodiment 1 of this application.

[0040] Figure 3 It is the top view of the mold cover in Embodiment 1 of this application.

[0041] Figure 4 It is the cross-sectional view of the mold cover in Embodiment 1 of this application.

[0042] In the figure: 1. Base; 11. Die core; 12. Positioning hole; 2. Die cover; 21. Cover plate; 22. Positioning post. Specific implementation mode

[0043] The following embodiments further illustrate the present application in detail. Embodiment

[0044] Embodiment 1: An epoxy resin binder diamond lapping block contains the following raw materials by mass percentage: liquid epoxy resin E51 (epoxy value 0.48 - 0.52, selected from Nantong Xingchen Synthetic Materials) 30%, powdered epoxy resin 0781H (epoxy value 0.22 - 0.26, selected from Shanghai Rod New Materials) 5%, diamond abrasive with a particle size number of 3000 mesh 10%, 4,4'-methylenebis(aniline) curing agent 12.5%, auxiliary abrasive 9% (5% silicon carbide micropowder with a particle size of 3000 mesh and 4% white fused alumina), filler 31% (12% alumina with a particle size of 3000 mesh, 13% zinc oxide with a particle size of 4000 mesh, 6% calcium carbonate with a particle size of 3000 mesh), silicone defoamer 5% (Dow Corning ACP - 1400), diluent butyl glycidyl ether 2% (selected from Zhejiang Jiaxing Nanjian Biological Materials, model 501).

[0045] The production process of the above epoxy resin binder diamond lapping block includes the following steps: Mechanically stir the diamond abrasive, silicon carbide micropowder, white fused alumina, alumina, zinc oxide and calcium carbonate evenly, add liquid epoxy resin E51, powdered epoxy resin 0781H, curing agent, defoamer and diluent, stir into a slurry, and then inject it into the die core 11 of the mold by pouring. After scraping the slurry flat, cover the slurry with a nylon base cloth, and then cover the nylon base cloth with the die cover 2, so that the cover plate 21 on the die cover 2 fits with the die core 11. Set the temperature of the upper and lower plates of the hydraulic press to 100°C, press with a pressure of 800 kN for 30 min. After pressing and forming, open the die cover 2, blow out the lapping block with an air gun, and bond the lapping block to the resin bottom plate with an adhesive (such as 501 glue) to obtain the epoxy resin binder diamond lapping block.

[0046] See Figures 1 - 4, the mold includes a base 1 and a mold cover 2. The base 1 is provided with a mold core 11 for injecting slurry, and the mold cover 2 is connected with a cover plate 21 that cooperates with the mold core 11. The base 1 is provided with positioning holes 12 respectively located at the four corners of the base 1, and the mold cover 2 is connected with positioning posts 22 that cooperate with the positioning holes 12. The positioning posts 22 are inserted into the positioning holes 12. After the slurry is poured into the mold core 11, the slurry is scraped flat. After covering the slurry with a nylon base cloth, the cover plate 21 on the mold cover 2 is covered on the nylon base cloth, and the positioning posts 22 are inserted into the positioning holes 12. When pressure is applied, the cover plate 21 and the mold core 11 cooperate with each other to press the slurry in the mold core, so that it is pressed into shape to obtain the grinding block.

[0047] Example 2: An epoxy resin bonded diamond lapping block contains the following raw materials by mass percentage: liquid epoxy resin E51 (epoxy value 0.48 - 0.52, selected from Nantong Xingchen Synthetic Materials) 27.5%, powdered epoxy resin 0781H (epoxy value 0.22 - 0.26, selected from Shanghai Luode New Materials) 7.5%, diamond micropowder with a particle size of 3000 mesh 10%, auxiliary abrasive 6% (silicon carbide micropowder with a particle size of 3000 mesh), filler 36% (aluminum oxide with a particle size of 3000 mesh 15%, zinc oxide with a particle size of 4000 mesh 15% and calcium carbonate with a particle size of 3000 mesh 6%), 2-ethyl-4-methylimidazole curing agent 10.5%, defoaming agent 0.5%, and the defoaming agent is an epoxy resin defoaming agent selected from Shandong Zero Degree New Materials (brand number HS-018), diluent 2%, and the diluent is alkylene glycidyl ether, selected from Jiangsu Xinsu New Materials, model HK-6.

[0048] The production process of the above epoxy resin bonded diamond lapping block includes the following steps: After the diamond abrasive, silicon carbide micropowder, white corundum, aluminum oxide, zinc oxide and calcium carbonate are mechanically stirred evenly, liquid epoxy resin E51, powdered epoxy resin 0781H, 2-ethyl-4-methylimidazole curing agent, epoxy resin defoaming agent, and alkylene glycidyl ether diluent are added. After being stirred into a slurry, it is injected into the mold core 11 of the mold by pouring. After the slurry is scraped flat, it is covered with a nylon base cloth, and then the mold cover 2 is used to cover the nylon base cloth, so that the cover plate 21 on the mold cover 2 fits with the mold core 11. The temperatures of the upper and lower plates of the hydraulic press are set at 100°C, and it is pressed for 30 minutes with a pressure of 800 kN. After being pressed into shape, the mold cover 2 is opened, and the grinding block is blown out with an air gun. The grinding block is bonded to the resin base plate with an adhesive (such as 501 glue) to obtain the epoxy resin bonded diamond lapping block.

[0049] See Figures 1 - 4, the mold includes a base 1 and a mold cover 2. A mold core 11 for injecting slurry is provided on the base 1. A cover plate 21 that cooperates with the mold core 11 is connected to the mold cover 2. Positioning holes 12 are provided at the four corners of the base 1 respectively. Positioning columns 22 that cooperate with the positioning holes 12 are connected to the mold cover 2, and the positioning columns 22 are inserted into the positioning holes 12. After the slurry is poured into the mold core 11, the slurry is leveled. After covering a nylon base cloth on the slurry, the cover plate 21 on the mold cover 2 is covered on the nylon base cloth, and the positioning columns 22 are inserted into the positioning holes 12. When pressure is applied, the cover plate 21 and the mold core 11 cooperate with each other to press the slurry in the mold core, so that it is pressed into shape to obtain a grinding block.

[0050] Example 3-9: An epoxy resin bonded diamond lapping block, which is different from Example 1 in that the mass percentages of the raw materials are as shown in Table 1.

[0051] Table 1 Raw material dosages of diamond lapping blocks in Examples 1-9 Example 10: An epoxy resin bonded diamond lapping block, which is different from Example 1 in that the diamond abrasive is diamond particles with indium-doped zinc oxide deposited on the surface, and the others are the same. The preparation method of the diamond particles with indium-doped zinc oxide deposited on the surface is as follows: 1 g of zinc oxide powder and 0.2 g of indium element are mixed evenly and placed in a high-temperature furnace. The source is placed at the highest temperature. Using nitrogen as the carrier gas and diamond particles as the substrate, the substrate is placed downstream of the source, heated, and the high-temperature furnace is heated to 1350 °C at a rate of 8 °C / min, held for 1.5 h, and naturally cooled to room temperature. During this process, the pressure in the high-temperature furnace is maintained at 100 Pa and the nitrogen flow rate is 30 sccm.

[0052] Comparative example Comparative example 1: An epoxy resin bonded diamond lapping block, which is different from Example 1 in that an equal mass of liquid epoxy resin is used to replace the powdered epoxy resin.

[0053] Comparative example 2: An epoxy resin bonded diamond lapping block, which is different from Example 4 in that an equal mass of liquid epoxy resin is used to replace the powdered epoxy resin.

[0054] Comparative example 3: An epoxy resin bonded diamond lapping block, which is different from Example 1 in that the epoxy value of the liquid epoxy resin is 0.42-0.46, selected from Nantong Xingchen Synthetic Materials Co., Ltd., and the model is E44.

[0055] Comparative Example 4: An epoxy resin binder diamond abrasive block, which is different from Example 1 in that the epoxy value of the powdered epoxy resin is 0.1 - 0.14, selected from Yuhao Trading Co., Ltd. in Qingyuan City, and the model is E12.

[0056] Comparative Example 5: A phenolic resin binder diamond abrasive block, and the mass percentages of each component are: 50% of powdered phenolic resin, 10% of diamond abrasive, 10% of auxiliary abrasive (silicon carbide), and 30% of filler (10% of alumina, 10% of zinc oxide, and 10% of calcium carbonate). After mechanically stirring each raw material evenly, pour it into a mold, set the upper and lower plate temperatures of the hydraulic press to 150 °C, and press it for 60 min with a pressure of 900 N to form.

[0057] Performance detection test Prepare the abrasive blocks according to the methods in the examples and comparative examples, and refer to the following methods for performance detection, and record the detection results in Table 2.

[0058] 1. Hardness: Measure the hardness of the pure resin spline using the test method of GB / T531 - 1999. The ratio of liquid epoxy resin to powdered epoxy resin in the pure resin spline is the same as that in the example, the size of the spline is 40 mm * 10 mm * 8 mm, and the test instrument is an LX - D type Shore hardness tester. Take the average value of 5 tests.

[0059] 2. Flexural strength: Use a DZS - 20A digital display electronic flexural and compressive testing machine to test the flexural strength, and the size of the test sample is 40 mm * 10 mm * 8 mm; 3. Diamond holding force coefficient: Calculate according to F = 1 - Q, where Q = (M1 - M2) / M1, where M1 is the flexural strength value of the matrix (excluding diamond), M2 is the flexural strength value of the abrasive block containing diamond, and the larger the F value, the higher the holding force of the matrix on the diamond.

[0060] 4. Glossiness: Use a Shenzhen 3nh NHG60 60 - degree precision glossiness meter, project with a 60 - degree angle light source, and calculate the glossiness value through the light flux ratio.

[0061] 5. Abrasion resistance: Take a made diamond abrasive block, complete the grinding and polishing of luxury stone in a stone factory, test the square meters of the processed stone, and the running speed of the conveyor belt during the test is 0.9 m / min.

[0062] Table 2 Performance detection results of epoxy resin binder diamond abrasive blocks Combining the data in Table 2 and Examples 1-3 and Examples 4-6, it can be seen that the total proportion of powder epoxy resin and liquid epoxy resin used in Examples 1-3 is 35%, and the total proportion of powder epoxy resin and liquid epoxy resin in Examples 4-6 is 40%. The flexural performance of the abrasive block splines prepared in Examples 4-6 is better, and it is more wear-resistant, with a slightly lower gloss, but still meets the usage requirements and has no scratches.

[0063] In Examples 7-9, different types of fillers are used. Among them, polypropylene plastic powder and cryolite are added in Examples 7-8, and these two materials can reduce the material hardness and improve the toughness within a certain range; the titanium dioxide and talc powder used in Example 9 can improve the material hardness to a certain extent, increasing the sharpness and polish of the product.

[0064] In Example 10, deposited diamond particles are used, with the best wear resistance and the highest holding force coefficient.

[0065] In Comparative Example 1, only liquid epoxy resin is used and no powder epoxy resin is added. It can be seen that the abrasive block will have scratches, the flexural performance becomes worse, the wear resistance decreases, and the gloss is also slightly worse.

[0066] Compared with the abrasive block with a total epoxy resin content of 40 wt% in Example 4, in Comparative Example 2, no powder epoxy resin is added. It can be seen that the flexural property of the abrasive block becomes worse and the wear resistance weakens.

[0067] In Comparative Example 3 and Comparative Example 4, liquid epoxy resin with a decreased epoxy value and powder epoxy resin with a reduced epoxy value are used respectively. It can be seen that the hardness of the prepared abrasive block decreases, the flexural strength is large, but the gloss is greatly reduced and the grinding effect decreases significantly.

[0068] In Comparative Example 5, it is a phenolic resin cloth in powder form, with high hardness, a large molecular weight, a low diamond holding force coefficient, and scratches and a lower gloss during grinding.

[0069] This specific embodiment is only an explanation of the present application and does not limit the present application. Those skilled in the art can make modifications to this embodiment without creative contributions according to needs after reading this specification, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. An epoxy resin binder diamond lapping block, characterized in that, It comprises raw materials in the following weight percentages: 20 - 30% of liquid epoxy resin, 5 - 15% of powdered epoxy resin, 5 - 10% of diamond abrasive, 10 - 15% of curing agent, 5 - 10% of auxiliary abrasive, 25 - 40% of filler, 0.2 - 0.8% of defoaming agent, and 1 - 3% of diluent; The epoxy value of the liquid epoxy resin is 0.48 - 0.54; The epoxy value of the powdered epoxy resin is 0.22 - 0.

26.

2. The diamond abrasive block bonded with epoxy resin according to claim 1, characterized in that: The mass ratio of the liquid epoxy resin to the powdered epoxy resin is 3.6 - 6:

1.

3. The diamond lapping block with an epoxy resin binder according to claim 1, wherein: The liquid epoxy resin is E51 epoxy resin; the powdered epoxy resin is 0781H type epoxy resin.

4. The diamond grinding block with epoxy resin binder according to claim 1, characterized in that: The filler is selected from at least one of alumina, zinc oxide, calcium carbonate, talc powder, titanium dioxide, cryolite, silicon dioxide powder, and polypropylene powder.

5. The diamond abrasive block with an epoxy resin binder according to claim 1, characterized in that: The curing agent is at least one of aliphatic polyamines, aromatic polyamines, tertiary amine curing agents, imidazole curing agents, and anhydride curing agents.

6. The diamond brazing abrasive block with an epoxy resin binder according to claim 1, wherein: The particle size of the filler is 3000 - 5000 mesh.

7. The diamond grinding block with epoxy resin binder according to claim 1, wherein: The auxiliary abrasive is selected from at least one of white corundum, chrome corundum, and silicon carbide micropowder, and the particle size is 120 - 8000 mesh.

8. The diamond grinding block with an epoxy resin binder according to claim 1, characterized in that: The defoaming agent is silicone defoaming agent or epoxy resin defoaming agent; The diluent is butyl glycidyl ether or alkylene glycidyl ether.

9. The production process of the epoxy resin binder diamond grinding block according to any one of claims 1-8, characterized in that: It comprises the following steps: Mix the diamond abrasive uniformly with the auxiliary abrasive, filler, liquid epoxy resin, powdered epoxy resin, curing agent, defoaming agent, and diluent to obtain a slurry; Inject the slurry into a mold, cover the slurry with a nylon base cloth, perform die pressing at 800 - 900 kN for 20 - 30 min, and bond it to the bottom plate to obtain an epoxy resin bonded diamond lapping block.

10. The production process of the epoxy resin binder diamond lapping block according to claim 9, characterized in that: The mold comprises a base (1) and a mold cover (2). A mold core (11) for injecting the slurry is provided on the base (1), and a cover plate (21) that cooperates with the mold core (11) is connected to the mold cover (2); positioning holes (12) are provided on the base (1), and positioning posts (22) that cooperate with the positioning holes (12) are connected to the mold cover (2).

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