Super-hard heavy-load steel rail grinding wheel and preparation method thereof

Abstract

The invention discloses a superhard heavy-load steel rail grinding wheel and a preparation method thereof.The structure of the grinding wheel is a pin-disc type structure, the grinding wheel specifically comprises a cylindrical superhard pin body and a grinding wheel body, the cylindrical superhard pin body serves as a framework playing a main grinding role and is embedded in the grinding wheel body, and then the cylindrical superhard pin body and the grinding wheel body are pressed together to form a parallel grinding wheel; according to the manufactured super-hard heavy-load steel rail grinding wheel, the super-hard pin body and the grinding wheel body have the same forming density, good balance and excellent performance, the bending strength reaches 86.6 MPa, the Rockwell hardness reaches 68-71 HRA, the rotation strength is not broken within 30 seconds at the 1.5-time working speed, and the grinding wheel has the advantages that the grinding wheel is not prone to breakage at the working speed of 50 m / s; the steel rail has good sharpness, wear resistance, heat dissipation and stability in the process of grinding the steel rail under the grinding pressure of 260 Kg / cm < 2 >, the surface of the steel rail is free of burn blue spots, surface lines are clear and uniform, the surface roughness Ra is within the range of 1-4 microns, and the cost is controlled at a low level.

Description

Technical Field

[0001] The invention belongs to the field of superhard abrasive tools, and in particular relates to a superhard heavy-load rail grinding wheel and a preparation method thereof. Background Art

[0002] China's high-speed rail has made the world appreciate the "China speed". As the main component of the railway system, the rails provide guidance for locomotives and vehicles, and also transmit the locomotive loads they bear to the railway subgrade or bridges and tunnels. Due to the complex and variable load impact from the vertical, lateral and longitudinal directions during service, various damages and defects are prone to occur on the surface and inside. Railway rail maintenance and repair have become the most important logistical support for China's railway industry. Rail grinding is an indispensable means to avoid and eliminate surface defects of rails and ensure the safe operation of railways. High-speed rail technology requires that the grinding height difference of the track plate is less than 0.2mm, and the grinding accuracy of the rails must reach 0.1mm. As the time window for high-speed rail maintenance continues to shrink, the requirements for the grinding efficiency and service life of the rails continue to increase. In this way, it is necessary to increase the grinding pressure, that is, to implement medium or heavy load grinding to improve the grinding efficiency, so as to meet the requirements of completing the grinding operation quickly in a short time.

[0003] Traditional super-hard abrasives are made by mixing super-hard abrasives with binders and auxiliary materials into uniform molding materials, and then through molding processes, various abrasive products are prepared. The super-hard abrasive grains are irregularly distributed throughout the entire space of the abrasive. However, during the grinding process, the dynamically effective abrasive grains only account for a very small part of the total number of abrasive grains. The super-hard abrasives are densely arranged locally, and only the abrasive grains in the front play the main grinding role, while the abrasive grains in the back do not play a role, resulting in a large amount of super-hard abrasive waste. If the concentration of super-hard abrasives is evenly reduced, the working load on a single abrasive grain will be too large, resulting in the breakage and shedding of the abrasive, which will shorten the life of the abrasive. Summary of the invention

[0004] The purpose of the present invention is to prepare a new type of heavy-load, high-efficiency, wear-resistant grinding wheel suitable for high-speed railway rail grinding, and proposes a preparation method of a superhard heavy-load rail grinding grinding wheel. The structure of the grinding wheel is a pin-disc structure, specifically including a cylindrical superhard pin body and a grinding wheel body. The cylindrical superhard pin body serves as a skeleton that plays a major grinding role, is embedded in the main grinding wheel, and then pressed together to form a parallel grinding wheel; the superhard pin body and the grinding wheel body have the same molding density and good balance; the formula of the cylindrical superhard pin body is 25~40% by weight of a binder, 25~35% by weight of a superhard abrasive, 15~25% by weight of a common abrasive, 3~7% by weight of a wetting agent, and 5%~10% by weight of an auxiliary material; the formula of the grinding wheel body is 25~40% by weight of a binder, 40~60% by weight of a common abrasive, 3~7% by weight of a wetting agent, and 5%~10% by weight of an auxiliary material.

[0005] Preferably, the cylindrical superhard pin body is arranged in a spiral shape in the grinding wheel. The arrangement shape is designed according to the force curve of the grinding wheel in the rotating grinding state, which plays the role of buffering the impact force exerted on the superhard pin body during the grinding process, so that the force is more uniform and the grinding is smoother during heavy or medium load grinding, which is conducive to the grinding wheel to achieve a more stable working state and processing effect.

[0006] Preferably, the superhard abrasive is graphene oxide coated with cubic boron nitride (CBN @GO), and the cubic boron nitride particle size is one of 30 / 35, 35 / 40, 40 / 45, 45 / 50, 50 / 60, 60 / 70, 70 / 80, 80 / 100 mesh or several particle sizes are mixed together; the preparation process of CBN @GO is as follows: graphene oxide is dispersed in deionized water at a concentration of 1wt%, ultrasonically dispersed for 30 minutes, and then strongly mechanically stirred for 30 minutes. Cubic boron nitride is added at a concentration of 20wt%, mechanically stirred for 30 minutes, and then allowed to stand, filtered, and dried.

[0007] Preferably, the common abrasives in the superhard pin body and the grinding wheel body are one or a mixture of zirconium corundum, white corundum, single crystal corundum, sintered corundum, and hollow ball abrasives, and the particle size of the common abrasive is one or a mixture of 30, 35, 40, 45, 50, 60, 70, 80, and 100 meshes.

[0008] Preferably, the binder in the cylindrical superhard pin body and the grinding wheel body is a ternary composite binder of polyimide, phenolic resin and amino resin, and the weight ratio thereof is 3:6:1.

[0009] Preferably, the auxiliary materials in the cylindrical superhard pin body are one or a mixture of corundum powder, talcum powder, calcium carbonate powder, barium sulfate powder, silicon dioxide powder, chromium oxide powder, pyrite, cryolite, hexagonal boron nitride, magnesium oxide powder, zinc oxide powder, iron oxide powder, copper powder, aluminum hydroxide powder, magnesium hydroxide powder, graphite powder, hollow ball abrasive powder, etc.

[0010] Preferably, both the cylindrical superhard pin body and the grinding wheel body use phenolic resin liquid as a wetting agent.

[0011] Preferably, the molding materials of the cylindrical superhard pin body and the grinding wheel body are mixed by a double-shaft mixer, and the mixing order is: first mix the abrasive and the wetting agent, then add the resin powder and mix, then add the filler, and after mixing, pass through a 20-mesh sieve.

[0012] Preferably, the cylindrical superhard pin body and the grinding wheel body are both formed by hot pressing technology with a pressure of 800KN, and are completed through preheating, exhaust, heat preservation and pressure holding processes, and a secondary curing process is performed after demolding.

[0013] A superhard heavy-load rail grinding wheel is prepared by any of the above preparation methods.

[0014] Beneficial effects achieved by the present invention: The invention carries out scientific structural design of the grinding wheel, and through modification of super-hard abrasive and binder, matching of auxiliary materials, adjustment of formula and optimization of process, the super-hard heavy-load rail grinding wheel prepared by the invention has excellent performance, bending strength reaches 86.6MPa, Rockwell hardness reaches 68-71HRA, rotation strength does not break for 30 seconds at 1.5 times the working speed, and the grinding wheel works at 50m / s at 260Kg / cm 2 The rails have good sharpness, wear resistance, heat dissipation and stability in the process of grinding under grinding pressure. There are no blue spots on the rail surface, the surface texture is clear and uniform, the surface roughness Ra is in the range of 1~4μm, and the cost is controlled at a low level. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 . Schematic diagram of the Φ150×40×50 pin-disc spiral arrangement grinding wheel structure; Figure 2 . Φ260×40×154 pin-disc spiral arrangement grinding wheel structure schematic diagram; Figure 3 . Φ150×40×50 Schematic diagram of the circular pin body with two layers of evenly arranged grinding wheels; Figure 4 . Schematic diagram of the structure of the grinding wheel with two layers of uniform arrangement of Φ150×40×50 triangular pins; Figure 5. Partial magnified view of the grinding wheel; Figure 6 Example 1 A magnified view of the surface of a rail being polished by a grinding wheel; Figure 7 Example 1 Grinding wheel grinding rail surface roughness; Figure 8 . Example 2 Grinding wheel to grind the surface roughness of the rail. DETAILED DESCRIPTION

[0016] The present invention will be further described below in conjunction with specific embodiments. Example

[0017] The preparation specification of the superhard pin is Φ8×40, and the formula is: 30 parts by weight of 35 / 40 mesh CBN @GO, 20 parts by weight of 35 mesh zirconium corundum, 13 parts by weight of 320 mesh white corundum, 5 parts by weight of phenolic resin liquid, 5 parts by weight of chromium trioxide, 2 parts by weight of pyrite, and 25 parts by weight of ternary composite binder powder; the molding density is 3.0g / cm 3 ; Hot pressing molding, molding pressure is 800kN; Hot pressing temperature is 185 degrees, preheating time is 3 minutes, exhaust once every 5 minutes, exhaust three times in total, and holding time is 45 minutes; the curing process is 80℃ insulation for 1 hour, 100℃ insulation for 1 hour, 140℃ insulation for 2 hours, 180℃ insulation for 2 hours, 220℃ insulation for 3 hours, 240℃ insulation for 4 hours, and natural cooling to room temperature.

[0018] The preparation specification of the grinding wheel body is Φ150×40×50, and the formula is: 50 parts by weight of 35 mesh zirconium corundum, 13 parts by weight of 320 mesh white corundum, 5 parts by weight of phenolic resin liquid, 5 parts by weight of chromium trioxide, 2 parts by weight of pyrite, and 25 parts by weight of ternary composite binder; the molding density is 3.0g / cm 3 ; Place 20 super-hard pins according to Figure 1 After the arrangement shown is embedded in the mold, the evenly mixed grinding wheel body molding material is filled in, and then hot-pressed. The molding and curing process is the same as above, and the mold is naturally cooled to room temperature. Example

[0019] The preparation specification of the superhard pin is Φ8×40, and the formula is: 25 parts by weight of 35 / 40 mesh CBN @GO; 10 parts by weight of 60 / 70 mesh CBN @GO, 20 parts by weight of 35 mesh zirconium corundum; 8 parts by weight of 320 mesh white corundum, 5 parts by weight of phenolic resin liquid, 5 parts by weight of zinc oxide, 2 parts by weight of cryolite, and 25 parts by weight of ternary composite binder; the molding density is 3.0g / cm 3 ; Hot pressing molding, molding and curing process are the same as in Example 1, and naturally cooling down to room temperature.

[0020] The preparation specification of the grinding wheel body is Φ260×40×154, and the formula is: 45 weight parts of 35 mesh zirconium corundum, 10 weight parts of 60 mesh zirconium corundum, 8 weight parts of 320 mesh white corundum, 5 weight parts of phenolic resin liquid, 5 weight parts of zinc oxide, 2 weight parts of cryolite, and 25 weight parts of ternary composite binder; the molding density is 3.0g / cm 3 ; 56 super hard pins are placed according to Figure 2 The arrangement shown is embedded in a mold and hot pressing is used. The molding and curing process is the same as in Example 1, and the mold is naturally cooled to room temperature.

[0021] Comparative Example 1: The specifications, formula, and molding process of the superhard pin body are the same as those in Example 1, and the specifications, formula, and molding process of the grinding wheel body are also exactly the same as those in Example 1.

[0022] The main difference between Comparative Example 1 and Example 1 is that the arrangement of the superhard pins in Comparative Example 1 is as follows: Figure 3 As shown, the two layers are evenly arranged in a ring shape, and the rest of the formula and process are the same as those in Example 1.

[0023] Comparative Example 2: The specification of the superhard pin body is an equilateral triangle with a side length of 10.8 mm in cross section. The formula and molding process are the same as those in Example 1. The specification, formula and molding process of the grinding wheel body are also exactly the same as those in Example 1.

[0024] The main difference between Comparative Example 2 and Example 1 is that the superhard pin in Comparative Example 2 has a cross section of an equilateral triangle with a side length of 10.8 mm, and its arrangement is as follows: Figure 4 As shown, the two layers are evenly arranged in a ring shape, and the rest of the formula and process are the same as those in Example 1.

[0025] Comparative Example 3: The grinding wheel specification is Φ150×40×50, and the formula is: 50 weight parts of 35 mesh zirconium corundum, 13 weight parts of 320 mesh white corundum, 5 weight parts of phenolic resin liquid, 5 weight parts of chromium trioxide, 2 weight parts of pyrite, and 25 weight parts of ternary composite binder; the molding density is 3.0g / cm 3 , hot pressing is adopted, and the molding and curing process are exactly the same as the grinding wheel body preparation process of Example 1.

[0026] The main difference between Comparative Example 3 and Example 1 is that no superhard pin is embedded in Comparative Example 3, and the rest of the formula and process are the same as those for the main grinding wheel preparation in Example 1.

[0027] Comparative Example 4: The grinding wheel specifications are Φ150×40×50, and the formula is: 2 parts by weight of 35-mesh CBN@GO, 48 parts by weight of 35-mesh zirconium corundum, 13 parts by weight of 320-mesh white corundum, 2 parts by weight of pyrite, 5 parts by weight of phenolic resin liquid, 5 parts by weight of chromium trioxide, and 25 parts by weight of ternary composite binder; the molding density is 3.0g / cm 3 , hot pressing is adopted, and the molding and curing process are exactly the same as the grinding wheel body preparation process of Example 1.

[0028] The main difference between Comparative Example 4 and Example 1 is that no superhard pin is embedded in Comparative Example 4, but superhard CBN abrasive is added to the formula in the same proportion as in Example 1, and the rest of the formula and process are the same as the main grinding wheel material of Example 1.

[0029] Comparative Example 5: The preparation specifications of the superhard pin are the same as those in Example 1, and the formula is: 30 parts by weight of 35 / 40 mesh CBN@GO, 20 parts by weight of 35 mesh zirconium corundum, 33 parts by weight of 320 mesh white corundum, 5 parts by weight of chromium trioxide, 2 parts by weight of pyrite, and 30 parts by weight of ternary composite binder; the molding density is 3.0 g / cm 3 ; Hot pressing molding, molding and curing process are the same as in Example 1.

[0030] The preparation specifications of the grinding wheel body are the same as those in Example 1, and the formula is: 50 parts by weight of 35-mesh zirconium corundum, 13 parts by weight of 320-mesh white corundum, 5 parts by weight of chromium trioxide, 2 parts by weight of pyrite, and 30 parts by weight of ternary composite binder; the molding density is 3.0 g / cm 3 ; Place 20 super-hard pins according to Figure 1 The arrangement shown is embedded in a mold and hot pressing is used. The molding and curing process is the same as in Example 1.

[0031] The main difference between Comparative Example 5 and Example 1 is that phenolic resin wetting agent is not used in the formula of superhard pin body and grinding wheel body, the ternary composite binder is increased by 5 parts by weight, the sand-bond ratio is kept the same as that of Example 1, and the rest of the formula and process are the same as those of Example 1.

[0032] Comparative Example 6: The preparation specifications of the superhard pin are the same as those in Example 1, and the formula is: 30 parts by weight of 35 / 40 mesh CBN@GO, 20 parts by weight of 35 mesh zirconium corundum; 5 parts by weight of phenolic resin liquid, 18 parts by weight of chromium trioxide, 2 parts by weight of pyrite, and 25 parts by weight of ternary composite binder; the molding density is 3.0 g / cm 3 ; Hot pressing molding, molding and curing process are the same as in Example 1.

[0033] The preparation specifications of the grinding wheel body are the same as those in Example 1, and the formula is: 50 parts by weight of 35-mesh zirconium corundum, 5 parts by weight of phenolic resin liquid, 18 parts by weight of chromium trioxide, 2 parts by weight of pyrite, and 25 parts by weight of ternary composite binder; the molding density is 3.0 g / cm 3 ; Place 20 super-hard pins according to Figure 1 The arrangement shown is embedded in a mold and hot pressing is used. The molding and curing process is the same as in Example 1.

[0034] The main difference between Comparative Example 6 and Example 1 is that 320 mesh white corundum auxiliary abrasive is not used in the superhard pin and grinding wheel main body formula, its weight is increased to chromium trioxide, the sand-bond ratio is kept the same as that in Example 1, and the rest of the formula and process are the same as those in Example 1.

[0035] Comparative Example 7: The preparation specifications of the superhard pin are the same as those in Example 1, and the formula is: 30 parts by weight of 35 / 40 mesh CBN@GO, 20 parts by weight of 35 mesh zirconium corundum, 18 parts by weight of 320 mesh white corundum, 5 parts by weight of phenolic resin liquid, 2 parts by weight of pyrite, and 25 parts by weight of ternary composite binder; the molding density is 3.0 g / cm 3 ; Hot pressing molding is adopted, and the molding and curing process are the same as in Example 1.

[0036] The preparation specifications of the grinding wheel body are the same as those in Example 1, and the formula is: 50 parts by weight of 35-mesh zirconium corundum, 18 parts by weight of 320-mesh white corundum, 5 parts by weight of phenolic resin liquid, 2 parts by weight of pyrite, and 25 parts by weight of ternary composite binder; the molding density is 3.0 g / cm 3 ; Hot pressing molding, molding and curing process are the same as in Example 1.

[0037] The main difference between Comparative Example 7 and Example 1 is that the auxiliary material chromium trioxide auxiliary abrasive is not used in the formula of the superhard pin and the grinding wheel main body, and its weight is increased to 320 mesh white corundum, and the sand-bond ratio is kept the same as that of Example 1, and the rest of the formula and process are the same as those of Example 1.

[0038] Comparative Example 8: The CBN@GO in the superhard pin body is replaced with ordinary CBN of the same particle size. The rest of the formula, specifications and molding process of the superhard pin body are the same as those in Example 1. The specifications, formula and molding process of the grinding wheel body are also exactly the same as those in Example 1.

[0039] The main difference between Comparative Example 8 and Example 1 is that the superhard pin CBN@GO is replaced by ordinary CBN with the same particle size.

[0040] Comparative Example 9: The ternary composite binder used in the superhard pin body and the grinding wheel body is completely replaced with phenolic resin powder. The rest of the formula, specification and molding process of the superhard pin body and the grinding wheel body are the same as those in Example 1.

[0041] The main difference between Comparative Example 9 and Example 1 is that the ternary composite binder in Example 1 is completely replaced by phenolic resin powder.

[0042] Comparative Example 10: The ternary composite binder used in the superhard pin and the grinding wheel body is completely replaced with polyimide resin powder. The rest of the formula, specification and molding process of the superhard pin and the grinding wheel body are the same as those in Example 1.

[0043] The main difference between Comparative Example 10 and Example 1 is that the ternary composite binder in Example 1 is completely replaced by polyimide resin powder.

[0044] The grinding wheels prepared in the above embodiments and comparative examples and the imported HTT grinding wheels were respectively used to grind high-speed rails on a GMC-96X rail grinding machine. The grinding pressure was 260 kgf, the workpiece speed was 1 m / s, and the grinding wheel speed was 50 m / s. The grinding removal thickness was calculated and the surface roughness of the samples was tested. The grinding performance comparison results are shown in Table 1: Table 1 Effects of different grinding wheels on rail grinding Grinding wheel type Single-pass grinding removal thickness (μm) Wear ratio Surface roughness of workpiece after processing Ra (μm) Surface condition of workpiece after processing Pass rate Imported HTT grinding wheel 100~150 5~10 >10 No burn marks, unclear lines, and miscellaneous lines <90% Example 1 195 21 1.30 No burns, clear and even lines, no streaks >97% Example 2 210 21 3.05 No burns, clear and even lines, no streaks >97% Comparative Example 1 180 15 5.54 No burn marks, unclear lines, no streaks <90% Comparative Example 2 205 11 12.53 No burn marks, unclear lines, and mixed lines <90% Comparative Example 3 115 6 6.12 No burns, clear and even lines, no streaks <80% Comparative Example 4 165 12 5.89 No burn marks, clear and uniform lines, no streaks <80% Comparative Example 5 125 16 4.71 No burn marks, uneven texture, no miscellaneous lines <80% Comparative Example 6 115 15 10.36 No burn marks, uneven texture, no miscellaneous lines <80% Comparative Example 7 140 18 12.02 There are burn marks, unclear lines and miscellaneous lines <80% Comparative Example 8 205 17 7.29 There are burn marks, clear lines and miscellaneous lines <80% Comparative Example 9 150 16 6.04 No burns, clear lines, occasional streaks <90% Comparative Example 10 165 18 6.61 No burns, clear lines, occasional streaks <90% The grinding wheels prepared in Example 1 and Example 2 are not only sharp and durable in the process of grinding existing high-speed rails, but also can ensure that the workpiece has clear and uniform texture, no miscellaneous lines, and no burns, thereby achieving high-quality and high-efficiency processing of high-speed rail workpieces.

[0045] Compared with the embodiment, the wear ratio of comparative example 1 is reduced, the rail surface texture is unclear, and the yield rate is reduced; In comparative example 2, the grinding removal amount increased slightly, but the wear ratio decreased more significantly, the surface roughness was poor, the rail surface texture was unclear, and the yield rate decreased; In comparative example 3, the grinding removal amount decreased significantly, and the wear ratio decreased significantly, the surface roughness was slightly worse, and the yield rate was low; Comparative Example 4 shows a decrease in grinding removal, relatively low wear, and low yield rate; The grinding removal of comparative example 5 was greatly reduced, the texture was uneven, and the yield rate was low; Comparative Example 6 has low grinding removal, poor surface roughness, uneven texture, and low yield rate; Comparative Example 7 has a low grinding removal amount, poor surface roughness, blue spot burns, unclear lines and miscellaneous lines, and a low yield rate; Comparative Example 8 has acceptable grinding removal, slightly poor surface roughness, blue spot burns, miscellaneous lines, and low yield rate; Comparative Example 9 has a low grinding removal amount, occasional streaks, and a low yield rate; Comparative Example 10 has a low grinding removal amount, occasional streaks, and a low yield rate; The above description shows that the design and preparation formula of the superhard heavy-load rail grinding wheel of the present invention have certain advantages.

[0046] It should be understood that the above description of the embodiments is relatively detailed and cannot be regarded as limiting the scope of protection of the present invention. For ordinary technicians in the technical field to which the present invention belongs, various modifications such as changes in size, shape, number, replacement, simple combination, etc. can be made without departing from the concept of the present invention, which should be regarded as falling within the scope of protection of the present invention.

Claims

1. A method for preparing a superhard heavy-load rail grinding wheel, characterized in that: The structure of the grinding wheel is a pin-disc structure, specifically including a cylindrical superhard pin body and a grinding wheel body. The cylindrical superhard pin body serves as a skeleton that plays a major grinding role and is embedded in the grinding wheel body, and then pressed together to form a parallel grinding wheel; wherein the superhard pin body and the grinding wheel body have the same molding density, and the formula of the cylindrical superhard pin body is 25-40% by weight of a binder, 25-35% by weight of a superhard abrasive, 15-25% by weight of a common abrasive, 3-7% by weight of a wetting agent, and 5%-10% by weight of an auxiliary material; the formula of the grinding wheel body is 25-40% by weight of a binder, 40-60% by weight of a common abrasive, 3-7% by weight of a wetting agent, and 5%-10% by weight of an auxiliary material.

2. The preparation method according to claim 1, characterized in that: The cylindrical superhard pins are arranged in a spiral shape in the grinding wheel.

3. The preparation method according to claim 1, characterized in that: The superhard abrasive used for the cylindrical superhard pin is cubic boron nitride coated with graphene oxide, and the particle size of the cubic boron nitride is one of 30 / 35, 35 / 40, 40 / 45, 45 / 50, 50 / 60, 60 / 70, 70 / 80, 80 / 100 mesh or a mixture of several particle sizes.

4. The preparation method according to claim 1, characterized in that: The common abrasives used for the superhard pin and the grinding wheel body are one or a mixture of zirconium corundum, white corundum, single crystal corundum, sintered corundum, and hollow ball abrasives, and the particle size of the common abrasive is one or a mixture of 30, 35, 40, 45, 50, 60, 70, 80, and 100 meshes.

5. The preparation method according to claim 1, characterized in that: The binder in the cylindrical superhard pin body and the grinding wheel body is a ternary composite binder of polyimide, phenolic resin and amino resin, and the weight ratio is 3:6:

1.

6. The preparation method according to claim 1, characterized in that: The auxiliary materials used for the cylindrical superhard pin are one or a mixture of corundum powder, talc powder, calcium carbonate powder, barium sulfate powder, silicon dioxide powder, chromium oxide powder, pyrite, cryolite, hexagonal boron nitride, magnesium oxide powder, zinc oxide powder, iron oxide powder, copper powder, aluminum hydroxide powder, magnesium hydroxide powder, graphite powder, hollow ball abrasive powder, etc.

7. The preparation method according to claim 1, characterized in that: The cylindrical superhard pin body and the grinding wheel body both use phenolic resin liquid as a wetting agent.

8. The preparation method according to claim 1, characterized in that: The molding materials of the cylindrical superhard pin body and the grinding wheel body are mixed by a double-shaft mixer, and the mixing order is: first mix the abrasive and the wetting agent, then add the resin powder and mix, then add the filler, and after mixing, pass through a 20-mesh sieve.

9. The preparation method according to claim 1, characterized in that: The cylindrical super-hard pin body and the grinding wheel body are both formed by hot pressing technology with a pressure of 800KN. They are completed through preheating, exhaust, heat preservation and pressure holding processes, and a secondary curing process is carried out after demoulding.

10. A superhard heavy-load rail grinding wheel prepared by the preparation method according to any one of claims 1 to 9.

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