A method for preparing fibrous diamond agglomerated abrasive and its application in diamond abrasives.

Abstract

This invention discloses a method for preparing fibrous diamond agglomerates and their application in diamond abrasives. Diamond and low-melting-point glass powder are bonded to the inner fiber framework of graphite fiber felt using polyvinyl alcohol, and then sintered to form diamond agglomerates coated on the graphite fiber felt. The diamond agglomerates coated on the graphite fiber felt are then broken up, pulverized, and sieved to obtain fibrous diamond agglomerates. Diamond resin polishing pads are prepared using epoxy resin as a binder and the fibrous diamond agglomerates as the abrasive component. Due to its fibrous, highly cohesive, and agglomerated structure, the diamond agglomerates are less prone to detachment during polishing, resulting in high diamond utilization. The fiber shape facilitates heat conduction, preventing localized high temperatures that could cause resin thermal decomposition during polishing, thus extending the lifespan of the diamond resin polishing pad. Furthermore, the diamond agglomerates generate pores during preparation, which improve polishing accuracy and prevent surface scratches. Therefore, fibrous diamond agglomerates have promising applications in the preparation of diamond abrasives.

Description

Technical Field

[0001] This invention relates to the field of diamond abrasives, and more specifically to a method for preparing fibrous diamond agglomerated abrasives and their application in diamond grinding tools. Background Technology

[0002] With the rapid development of the building decoration industry, the demand for building materials such as ceramics, stone, and concrete is increasing daily. Generally speaking, building materials need to undergo surface treatment before use, and as people's aesthetic requirements improve, the requirements for the surface treatment effect of building materials are also getting higher and higher. The cutting, shaving, and grinding of material surfaces cannot be separated from processing tools, especially for ceramics and stone with high hardness and wear resistance, which places more and higher demands on the performance of processing tools.

[0003] Diamond abrasives are widely used in the surface polishing of hard materials due to their high grinding force, low grinding heat, and high grinding ratio. To date, domestically produced diamond abrasives mainly include sintered metal-bonded diamond abrasives and resin-bonded diamond abrasives. Sintered metal-bonded diamond abrasives, due to their high hardness and strength, often fail to achieve the required polishing degree when processing flat surfaces, and are therefore generally used for rough polishing. Resin-bonded diamond abrasives, on the other hand, offer advantages such as good elasticity, high strength, impact resistance, short production cycle, good self-sharpening properties during grinding, high grinding efficiency, and good surface finish, playing an increasingly prominent role in the polishing field. However, because resin binders have poor heat resistance and lower mechanical strength than ceramics and metals, they wear out quickly during polishing, resulting in a shorter tool life. Furthermore, due to the inertness of the diamond surface and the low bonding strength between the diamond and resin, diamond is easily detached from the polished surface under external impact during polishing, reducing the tool's self-sharpening properties and thus its polishing efficiency. Therefore, developing technologies to further improve the polishing efficiency and service life of resin-bonded diamond abrasives is a research hotspot and focus in the diamond resin abrasive industry.

[0004] Bonding fine-grained diamonds together with a binder to form diamond agglomerates is an effective method to improve diamond utilization and grinding efficiency. Liu Ju et al. prepared diamond agglomerates using a ceramic binder via a reverse microemulsion method and applied them to the preparation of high-efficiency resin grinding pads (Liu Ju, Wan Long. Functional Materials, 2018, 10(49):140-144). Meanwhile, many patent applications are dedicated to the preparation process of agglomerates (US 4393021; ​​CN 116042179 A; CN116218469 A and CN 117003581 A, etc.). Currently, the prepared diamond agglomerates are still mainly spherical or granular, and other shapes of diamond agglomerates have not yet been seen. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing fibrous diamond agglomerated abrasive and its application in diamond abrasives.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for preparing fibrous diamond agglomerated abrasive includes the following steps:

[0008] 1) Disperse diamond, low-melting-point glass powder and polyvinyl alcohol in distilled water and stir continuously for 5 to 60 minutes to obtain a mixed solution;

[0009] 2) Thoroughly immerse the commercially available graphite fiber felt in the mixed solution continuously stirred in step 1) for 2-3 minutes, then remove and treat in an oven at 110-120°C for 0.5-1.5 hours; then immerse the dried graphite fiber felt in the above mixed solution for 2-3 minutes, then remove and treat in an oven at 110-120°C for 0.5-1.5 hours; repeat the above operation 4-10 times;

[0010] 3) Treat the impregnated graphite fiber felt at 450–550°C for 0.5–6 hours;

[0011] 4) After the graphite fiber felt processed in step 3) is broken up, crushed, and sieved, fibrous diamond agglomerate abrasive is obtained.

[0012] The diamond has a particle size of 0.5–7 μm.

[0013] The low-melting-point glass powder has a particle size of 1–5 μm and a melting point of 450–550 °C.

[0014] The mass ratio of diamond, low-melting-point glass powder, polyvinyl alcohol and distilled water is 1:0.3 to 1:0.2 to 0.5:2 to 5.

[0015] The commercially available graphite fiber felt has a thickness of 0.8–2 mm and a density of 100–300 g / m³. 2 .

[0016] Application of the aforementioned fibrous diamond agglomerated abrasive in diamond abrasives: Diamond resin polishing pads are prepared using epoxy resin as a binder and fibrous diamond agglomerated abrasive as the abrasive component. The raw materials are as follows by weight:

[0017]

[0018] The diamonds are 0.5 to 7 μm in size.

[0019] The auxiliary abrasive is one or more of silicon carbide, alumina, zirconium oxide, boron nitride and cerium oxide, and the size of the auxiliary abrasive is 2 to 50 μm.

[0020] The preparation process of the diamond resin polishing pad is as follows: after the components are mixed evenly in proportion, they are poured into a tetrafluoroethylene mold, kept at 55-65°C for 2-4 hours, and then heated to 90°C and kept for 6-12 hours to obtain the diamond resin polishing pad.

[0021] This invention employs the above technical solution, bonding diamond and low-melting-point glass powder onto the internal fiber framework of graphite fiber felt using polyvinyl alcohol, then sintering to form diamond agglomerates coating the graphite fiber felt. The diamond agglomerates coating the graphite fiber felt are then broken up, pulverized, and sieved to obtain fibrous diamond agglomerate abrasive. Finally, using epoxy resin as a binder and the fibrous diamond agglomerate abrasive as the abrasive component, a diamond resin polishing pad is prepared. Compared with the prior art, this invention has the following advantages:

[0022] 1. The fibrous diamond agglomerate abrasive prepared by the present invention has a fibrous, highly cohesive and agglomerated structure. The diamond agglomerate abrasive is not easy to fall off during polishing, the diamond utilization rate is high, and the shape of the fiber is conducive to heat conduction, preventing local high temperature during polishing from causing thermal decomposition of the resin. Therefore, the diamond resin polishing pad has a long service life.

[0023] 2. In the preparation process of the fibrous diamond agglomerated abrasive of the present invention, the decomposition of polyvinyl alcohol introduces pores, which improves the self-sharpening property of the abrasive, thereby improving the polishing accuracy of the abrasive and preventing surface scratches. Detailed Implementation

[0024] To further explain the technical solution of the present invention, the present invention will be described in detail below through specific embodiments.

[0025] Example 1

[0026] (1) Preparation of fibrous diamond agglomerates

[0027] By weight, 1 part of 1μm diamond, 0.6 parts of 2μm glass powder with a melting point of 450℃ and 0.4 parts of polyvinyl alcohol are dispersed in 5 parts of distilled water and stirred continuously for 20 minutes to prepare a mixed solution.

[0028] A material with a thickness of 1 mm and a density of 150 g / m³ 2 Commercially available graphite fiber felt was thoroughly immersed in the above mixed solution under continuous stirring for 3 minutes. After removal, it was treated in an oven at 120°C for 1 hour. Then, the dried graphite fiber felt was immersed in the above mixed solution for 3 minutes, and after removal, it was treated in an oven at 120°C for 1 hour. The above operation was repeated 8 times.

[0029] The impregnated graphite fiber felt was treated at 500°C for 2 hours. Finally, the treated graphite fiber felt was broken up, crushed, and sieved to obtain fibrous diamond agglomerate abrasive.

[0030] (2) Preparation of diamond resin polishing pad

[0031] By weight, 80 parts of bisphenol A epoxy resin, 20 parts of polyetheramine curing agent D230, 30 parts of fibrous diamond agglomerate abrasive, 30 parts of 1μm diamond, 15 parts of 10μm alumina and 15 parts of 10μm silicon carbide are mixed evenly. The mixture is then poured into a PTFE mold and kept at 60°C for 4 hours. The temperature is then raised to 90°C and kept for 8 hours to obtain a diamond resin polishing pad.

[0032] Example 2

[0033] (1) Fibrous diamond agglomerates were prepared according to the method shown in Example 1.

[0034] (2) Preparation of diamond resin polishing pad

[0035] By weight, 80 parts of bisphenol A epoxy resin, 20 parts of polyetheramine curing agent D230, 35 parts of fibrous diamond agglomerated abrasive, 25 parts of 1μm diamond, 15 parts of 10μm alumina and 15 parts of 10μm silicon carbide are mixed evenly. The mixture is then poured into a tetrafluoroethylene mold and kept at 60°C for 4 hours. The temperature is then raised to 90°C and kept for 8 hours to obtain a diamond resin polishing pad.

[0036] Example 3

[0037] (1) Fibrous diamond agglomerates were prepared according to the method shown in Example 1.

[0038] (2) Preparation of diamond resin polishing pad

[0039] By weight, 80 parts of bisphenol A epoxy resin, 20 parts of polyetheramine curing agent D230, 40 parts of fibrous diamond agglomerate abrasive, 20 parts of 1μm diamond, 15 parts of 10μm alumina and 15 parts of 10μm silicon carbide are mixed evenly. The mixture is then poured into a PTFE mold and kept at 60°C for 4 hours. The temperature is then raised to 90°C and kept for 8 hours to obtain a diamond resin polishing pad.

[0040] Comparative Example 1

[0041] By weight, 80 parts of bisphenol A epoxy resin, 20 parts of polyetheramine curing agent D230, 60 parts of 1μm diamond, 15 parts of 10μm alumina and 15 parts of 10μm silicon carbide are mixed evenly. The mixture is then poured into a PTFE mold and kept at 60°C for 4 hours. The temperature is then raised to 90°C and kept for 8 hours to obtain a diamond resin polishing pad.

[0042] Tests were conducted on the examples and comparative samples. C30 concrete was used as the test surface, and dry polishing was performed using a KlindexRockey polishing device (41 kg, 175-400 rpm). The gloss, clarity, and polishing pad wear of the concrete surface were then measured.

[0043] Table 1. Gloss and clarity of the examples and comparative samples.

[0044]

[0045] As shown in Table 1, the fibrous diamond agglomerates prepared in this invention, when used to prepare diamond polishing pads, exhibit higher gloss, longer service life, and better thermal conductivity compared to diamond polishing pads without fibrous diamond agglomerates. Furthermore, with increasing amounts of fibrous diamond agglomerates, the polishing accuracy and service life also increase, demonstrating the excellent improvement effect of fibrous diamond agglomerates on diamond polishing pads.

[0046] As can be seen from the above embodiments, the diamond resin abrasive prepared by the fibrous diamond agglomerate of the present invention has the advantages of good polishing effect and long service life.

[0047] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing fibrous diamond agglomerated abrasive, characterized in that, Includes the following steps: 1) Disperse diamond, low-melting-point glass powder and polyvinyl alcohol in water and stir continuously for 5-60 minutes to obtain a mixed solution; 2) Thoroughly immerse the commercially available graphite fiber felt in the mixed solution continuously stirred in step 1) for 2-3 minutes, then remove and treat in an oven at 110-120°C for 0.5-1.5 hours; then immerse the dried graphite fiber felt in the above mixed solution for 2-3 minutes, then remove and treat in an oven at 110-120°C for 0.5-1.5 hours; repeat the above operation 4-10 times; 3) Treat the impregnated graphite fiber felt at 450~550℃ for 0.5~6 hours; 4) After the graphite fiber felt processed in step 3) is broken up, crushed, and sieved, fibrous diamond agglomerate abrasive is obtained.

2. The method for preparing fibrous diamond agglomerated abrasive according to claim 1, characterized in that, The melting point of the low-melting-point glass powder is 450~550℃.

3. The method for preparing fibrous diamond agglomerated abrasive according to claim 1, characterized in that, The diamond has a particle size of 0.5~7 μm, and the low melting point glass powder has a particle size of 1~5 μm.

4. The method for preparing fibrous diamond agglomerated abrasive according to claim 1, characterized in that, The mass ratio of diamond, low-melting-point glass powder, polyvinyl alcohol and water is 1:0.3~1:0.2~0.5:2~5.

5. A method for preparing fibrous diamond agglomerated abrasive according to claim 1, characterized in that, The commercially available graphite fiber felt has a thickness of 0.8~2 mm and a density of 100~300 g / m³. 2 .

6. The fibrous diamond agglomerated abrasive obtained by the preparation method according to any one of claims 1 to 5.

7. The application of the fibrous diamond agglomerated abrasive as described in claim 6 in diamond grinding tools, characterized in that, Diamond resin polishing pads were prepared using epoxy resin as a binder and fibrous diamond agglomerated abrasive as the abrasive component. The raw materials are as follows by weight: 80 parts of bisphenol A epoxy resin; 20 parts of polyetheramine curing agent D230; 30-50 parts of fibrous diamond agglomerated abrasive; 20-30 parts diamond; 10-30 parts of auxiliary abrasive.

8. The application according to claim 7, characterized in that, The auxiliary abrasive is one or more of silicon carbide, alumina, zirconium oxide, boron nitride, and cerium oxide.

9. The application according to claim 7, characterized in that, The diamond has a size of 0.5~7 μm, and the auxiliary abrasive has a size of 2~50 μm.

10. The application according to claim 7, characterized in that, The diamond resin polishing pad is prepared as follows: the raw materials are mixed evenly in proportion and then poured into a tetrafluoroethylene mold. The mixture is kept at 55-65°C for 2-4 hours, and then heated to 90°C and kept for 6-12 hours to obtain the diamond resin polishing pad.

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