Low-heat high-efficiency rail cutting blade for cutting railway rail and manufacturing method thereof

Abstract

The application discloses a low-heat and high-efficiency rail cutting piece for railway rail cutting and a manufacturing method thereof, and belongs to the technical field of tools for grinding, polishing or sharpening. In terms of mass parts, raw materials of the low-heat and high-efficiency rail cutting piece include: 100-135 parts of abrasive, 10-20 parts of resin bonding agent, 20-30 parts of functional filler, 4-8 parts of self-lubricating pore-forming material and 3-5 parts of wetting agent. The application has good cutting performance and burn resistance, can complete one-time cutting of a 60# rail within 90 seconds, ensures that the cutting surface has no obvious burn, and meets the rail cutting and machining tolerance requirement.

Description

Technical Field

[0001] This invention relates to the field of tools for grinding, polishing or sharpening, and in particular to a low-heat, high-efficiency rail cutting disc for railway rail cutting and its manufacturing method. Background Technology

[0002] With the continuous expansion of the railway network and the constant breakthroughs in train operating speeds, more stringent technical requirements have been placed on the processing quality and cutting efficiency of railway rails. The high strength, high hardness, and good toughness of railway rail materials significantly increase the difficulty of their cutting and processing. Currently, key processing equipment and consumables in the industry are still largely monopolized by imported products. Although these imported products have advantages in cutting efficiency and service life, they also suffer from high procurement costs, unstable supply cycles, and reliance on foreign core technologies, severely hindering the optimization of domestic railway construction costs and the development of an independent technological system.

[0003] Despite some technological breakthroughs in related fields in recent years, significant challenges remain in practical applications. Specifically, domestically produced cutting tools still lag behind in cutting efficiency, machining accuracy, and surface quality. This is particularly evident in the tendency to generate surface burns and burrs during cutting, resulting in rail sections that fail to meet process specifications. This not only increases subsequent processing costs but also poses a potential risk to railway operational safety. From a technological development perspective, existing cutting disc formulations and production processes largely follow traditional methods, lacking breakthroughs in materials science and process innovation. This makes it difficult to meet the demands of efficient and precise machining of modern railway rails, and this technological bottleneck has become a key factor restricting the overall upgrading of the industry.

[0004] The applicant's research team disclosed a self-lubricating composite filler for resin-based grinding wheels and its preparation method in Chinese patent publication number CN116038582A. This method involves bonding a solid lubricant and mechanically crushing it to prepare the self-lubricating composite filler. The surface of the crushed self-lubricating composite filler is chemically plated, and its irregular surface contains numerous protruding fibers, which can anchor with the resin binder of the grinding wheel, increasing the bonding strength between the composite filler and the resin grinding wheel matrix. During grinding, the resin-based self-lubricating composite filler can be released in real time at the grinding wheel / workpiece contact area along with the wear of the binder, thereby lubricating the contact area, reducing grinding heat generation, reducing thermal damage to the workpiece caused by grinding heat, and improving the surface finish of the workpiece. Furthermore, in Chinese patent publication number CN115741506A, the applicant's research team provided a high-strength, low-burn resin-based self-lubricating grinding wheel and its preparation method. The self-lubricating composite filler used in this invention has numerous protruding fibers on its surface, which can form anchor points with the resin binder, improving the bonding strength with the resin binder. Meanwhile, the self-lubricating particles are coated to increase their surface energy, making them easier to wet with resin. Lubricating components are added to the resin-based grinding wheel in the form of lubricating powder and self-lubricating composite filler, increasing the amount of lubricating components while ensuring high mechanical properties. During grinding, the lubricating components are released in real-time at the wheel / workpiece contact area as the bond wears, thus lubricating the contact area, significantly reducing grinding heat generation and temperature, and improving the thermal degradation problem caused by high temperatures in resin-based grinding wheels.

[0005] In further research and development, the inventors discovered that using fiber fillers as reinforcing agents to "anchor" the resin matrix with high aspect ratio fiber fillers to improve the strength of the resin matrix still failed to solve the problems of solid lubricating materials being prone to stacking, difficult to disperse, and slippage in sheet-like structures at high concentrations. Furthermore, considering the cutting force and edge retention requirements of the cutting disc, the matrix material cannot withstand higher contents of solid self-lubricating materials, and the design of grinding wheel components cannot be simply applied to the cutting disc application. Moreover, compared to grinding wheel processing, the cutting disc must meet indicators such as perpendicularity, parallelism, and flatness of the cut surface after operation, which places higher demands on its design.

[0006] In summary, a low-heat, high-efficiency rail cutting disc for railway rail cutting and its manufacturing method are proposed. By optimizing the formula and preparation process, the cutting efficiency and processing accuracy of the disc are improved, rail cutting burns are reduced, production costs are lowered, and the high requirements of railway rail cutting processing are met. This has an important role in promoting the development of railway construction engineering. Summary of the Invention

[0007] In view of the above-mentioned deficiencies of the prior art, in a first aspect of the present invention, a low-heat high-efficiency rail cutting disc with high cutting efficiency, low heat generation, and excellent cutting quality is provided. By weight, its raw materials include: 100-135 parts of abrasive, 10-20 parts of resin binder, 20-30 parts of functional filler, 4-8 parts of self-lubricating hole-forming material, and 3-5 parts of wetting agent.

[0008] Preferably, the abrasive comprises 30-40 parts of brown fused alumina, 60-80 parts of zirconium fused alumina, and 10-15 parts of cubic boron nitride.

[0009] Preferably, the resin adhesive comprises phenolic resin powder.

[0010] Preferably, the functional filler comprises 10-15 parts precipitated barium sulfate, 3-5 parts cryolite, 5-7 parts pyrite powder, and 2-3 parts calcium oxide.

[0011] Preferably, the self-lubricating pore-forming material is a carbonamide-graphite-molybdenum disulfide composite filler particle; its components include a pore-forming component and a self-lubricating component; wherein the pore-forming component is carbonamide, and the self-lubricating component is flake graphite powder and molybdenum disulfide powder.

[0012] This invention is based on the application of a cutting disc and features a specific design for its components. The self-lubricating pore-forming material eliminates the need for further additions of epoxy resin, aramid fiber, or other materials, achieving component optimization. The cutting disc, as a material that cuts by high-speed rotation of its outer circumference at a fixed position, is subjected to a force in only one direction during the cutting process—a force along the radius of rotation pointing towards the contact surface of the object being cut. Simultaneously, the force applied to the cutting disc during operation is relatively small, reducing the depth of cut and preventing dangerous situations such as chipping. Because the cutting disc operates in a fixed position without external traction or movement, and experiences relatively low force during operation, the cutting disc material is less sensitive to pore structure, eliminating the need for aramid fiber as a reinforcing material. Furthermore, the low pressure experienced by the cutting disc during operation eliminates the need for epoxy resin to enhance the pore's load-bearing capacity. The self-lubricating pore-forming filler, prepared by melt melting, contains no epoxy resin or aramid fiber, resulting in a higher content of pore-forming and self-lubricating components for the same particle size, which is more conducive to pore formation and the release of the self-lubricating material. In summary, the self-lubricating pore-forming filler selected in the cutting disc material does not contain aramid fiber or epoxy resin. By maximizing the proportion of pore-forming and self-lubricating components in the particles, better friction reduction, heat dissipation, and the ability to accommodate large-volume chips are achieved.

[0013] More preferably, the preparation method of the carbonamide-graphite-molybdenum disulfide composite filler particles includes the following steps: Molten carbonamide is mixed with flake graphite powder and molybdenum disulfide powder to achieve adhesion and encapsulation of the flake graphite powder and molybdenum disulfide powder. After cooling and molding, the mixture is crushed and sieved to obtain carbonamide-graphite-molybdenum disulfide composite filler particles.

[0014] More preferably, in the carbonamide-graphite-molybdenum disulfide composite filler particles, the proportions of each component by mass are 30-40 parts carbonamide, 6-9 parts graphite powder, and 4-6 parts molybdenum disulfide powder.

[0015] The carbonamide-graphite-molybdenum disulfide composite filler particles possess the hardness and strength required for their application at room temperature, and can maintain their shape and size during the preparation of the cutting discs. During the sintering and hardening process, the pore-forming material components decompose, leaving regular pores of a certain size in the cutting discs, thereby allowing the self-lubricating components to be released through the pores.

[0016] Preferably, the wetting agent comprises a phenolic resin liquid.

[0017] Preferably, the resin adhesive has a particle size of 280-350 mesh, the abrasive has a particle size of 16-24 mesh, the self-lubricating pore-forming filler has a particle size of 24-30 mesh, and the functional filler has a particle size of 100-150 mesh.

[0018] The mesh size of the self-lubricating pore-forming filler is selected based on the analysis of the chip size generated after on-site cutting and its compatibility with the abrasive size.

[0019] Based on the above-mentioned process limitations, in actual operation, as presented in one or more embodiments of the present invention, the carbonamide-graphite-molybdenum disulfide composite filler particles can be prepared according to the following steps or other suitable methods: 1) Weigh each raw material according to the proportion, and ball mill and disperse the graphite powder and molybdenum disulfide powder to obtain a mixed component; keep the mixed component at a certain temperature for later use. 2) Heat the carbamide to a melt temperature, then maintain the melt temperature while stirring; 3) The mixed components are added to the carbonamide melt, mixed, and degassed to obtain the mixed components; 4) The mixed components are cooled and shaped to obtain the shaped components; the shaped components are crushed and sieved to obtain carbonamide graphite molybdenum disulfide composite filler particles.

[0020] In a second aspect of the present invention, a method for preparing a low-heat, high-efficiency rail cutting disc according to the first aspect of the present invention is provided, comprising the following steps: (1) Weigh each raw material according to the proportion, mix brown corundum, zirconium corundum and cubic boron nitride to obtain mixed abrasive; add self-lubricating pore-forming filler to the mixed abrasive and mix to obtain abrasive component; mix resin binder and functional filler to make auxiliary component; dry the abrasive component and auxiliary component and place them in a constant temperature and humidity environment. (2) Add the wetting agent to the abrasive component and mix. After the mixture is completed, add the auxiliary component and mix to form a mixed component. The mixed component is sieved to obtain a loose cutting disc component. After sieving, it is left to stand in a constant temperature and humidity environment. (3) The cutting disc components are pressed with fiber reinforced mesh to form a cutting disc molded sample; the cutting disc molded sample is hot-pressed, sintered and hardened to obtain a low-heat, high-efficiency rail cutting disc.

[0021] During the preparation process, the self-lubricating pore-forming material exhibits high hardness and compressive strength at room temperature, enabling it to withstand the pressure applied during the cutting disc pressing process without breaking, maintaining its original size and morphology. During the hardening process of the cutting disc, at high temperatures, the pore-forming material components in the self-lubricating pore-forming material decompose, releasing the solid lubricant components. The solid lubricant has high heat resistance and maintains stable physical properties at the high-temperature hardening temperature of the cutting disc. The decomposition of the pore-forming material components during the cutting disc's hardening process creates a porous structure within the cutting disc, allowing the solid lubricant components to be released into the created pores after partial decomposition of the self-lubricating pore-forming material.

[0022] Based on the above technical solutions, the design concept and principle of this invention are as follows: In actual operation, the abrasive in the cutting disc undergoes two main actions during the cutting process: cutting and friction. Cutting action achieves material separation, while friction is the primary cause of heat generation. Traditional self-lubricating materials are typically added directly to the cutting disc's matrix material to release during cutting. However, this direct addition significantly reduces the cutting disc's mechanical strength and wear resistance, consequently decreasing its service life and safety.

[0023] This invention incorporates a self-lubricating pore-forming material, namely carbonamide-graphite-molybdenum disulfide composite filler particles, into traditional cutting disc materials. The difference between this self-lubricating pore-forming material and traditional self-lubricating materials lies in the fact that the self-lubricating pore-forming material creates pores through the decomposition of its components. This pore structure effectively accommodates the high-temperature heat source generated at the cutting disc / rail contact interface. After detaching from the contact interface, the high-temperature heat source is promptly expelled under the centrifugal force of the cutting disc. Simultaneously, the pores effectively increase the edge height of the abrasive within the cutting disc, enhancing its cutting performance. Meanwhile, the solid lubricating material is released through the pore structure at the cutting disc / rail contact surface, acting on the abrasive and rail surfaces to achieve lubrication at the abrasive-material contact interface, reducing frictional heat generation. This low-heat, high-efficiency rail cutting disc achieves low heat generation through both timely containment and removal of high-temperature heat sources and reduction of heat generation at the source.

[0024] Compared with the prior art, the present invention has the following advantages and beneficial effects: This invention provides a low-heat, high-efficiency rail cutting disc, which features high cutting efficiency, low heat generation, and excellent cutting quality, and has broad application prospects in railway rail cutting operations.

[0025] This invention provides a method for preparing a low-heat, high-efficiency rail cutting disc. The process is simple and easy to mass-produce, which helps to realize the large-scale production of low-heat, high-efficiency rail cutting discs. Attached Figure Description

[0026] Figure 1 The physical appearance of Example 1; Figure 2 This refers to the loss amount before and after a single cut in Example 1; Figure 3 The images show the burn marks on the cut surfaces of the rails in Example 1 and Comparative Example 1 after a single cut. Figure 4 The perpendicularity of the rail cut surfaces after a single cut is shown in Example 1 and Comparative Example 1. Figure 5 The parallelism of the rail cut surfaces after a single cut is shown in Example 1 and Comparative Example 1. Figure 6 The flatness of the cut surface of the rail after one cut is shown in Example 1 and Comparative Example 1. Detailed Implementation

[0027] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments that do not specify specific conditions were performed according to conventional methods and conditions, or as selected according to the product instructions.

[0028] Example 1 This embodiment provides a low-heat, high-efficiency rail cutting disc, the preparation method of which is as follows: (1) Preparation of self-lubricating pore-forming materials: 1) Weigh the raw materials according to the proportions. Place 8 parts of graphite powder and 6 parts of molybdenum disulfide powder in a ball mill for ball milling and dispersion. The ball mill speed is 300 rpm and the ball-to-material ratio is 1:0.6. The particle size of graphite powder and molybdenum disulfide powder should be above 200 mesh. After thorough mixing, a solid component is obtained. Place the solid component in an oven and heat it to 145 ℃. Keep it warm in the oven until it is ready for use. 2) Heat 40 parts of carbamide in an oven to 145 ℃; heat a constant temperature magnetic stirrer to 145 ℃, place the carbamide in the constant temperature magnetic stirrer, heat and stir until completely melted to obtain a carbamide melt, and keep it at the melting temperature while rotating. 3) Slowly pour the solid component into the carbonamide melt in 4 portions, stirring for 5 minutes after each pour. After thorough stirring, vacuum treat the material to remove air bubbles generated during stirring, and obtain the mixed component. 4) Place the mixed components in an oven for cooling and molding at a cooling rate of 0.8 ℃ / min until room temperature is reached to obtain the molded components; after mechanical crushing, the molded components are sieved and separated according to three gradients: 10~16 mesh, 16~24 mesh, and 24~36 mesh to obtain carbonamide graphite molybdenum disulfide composite filler particles with uniform particle size. (2) Premixed feed: Weigh 35 parts of brown fused alumina, 75 parts of zirconium fused alumina, and 10 parts of cubic boron nitride and mix them. The brown fused alumina should be 24 mesh, the zirconium fused alumina should be 16 mesh, and the cubic boron nitride should be 20 mesh. Feed the abrasive into a mixer and mix for 5 minutes to achieve full mixing and obtain the mixed abrasive. Weigh 8 parts of self-lubricating pore-forming filler; select 24-mesh carbonamide graphite molybdenum disulfide composite filler particles; add the carbonamide graphite molybdenum disulfide composite filler particles to the above mixed abrasive and mix thoroughly for 3 minutes to prepare the abrasive composition; Weigh 8 parts of phenolic resin powder, 3 parts of cryolite, 5.5 parts of pyrite, 2 parts of calcium oxide, and 10 parts of precipitated barium sulfate; select phenolic resin powder with a mesh size of 300 mesh and functional filler with a mesh size of 150 mesh; feed phenolic resin powder and functional filler into a drum mixer and mix thoroughly for 5 hours to prepare auxiliary material components. drying: The abrasive components and auxiliary components were dried in an oven at 60 ℃ for 24 h and then placed in a constant temperature and humidity environment. (3) Mixing: Phenolic resin liquid was selected as the wetting agent. Three parts of phenolic resin liquid were weighed and added to the abrasive component. The mixture was thoroughly mixed for 5 minutes. Then the auxiliary component was added and thoroughly mixed for 5 minutes to prepare the mixed component. Sieving: The mixed components were sieved through a 10-mesh sieve to obtain loose, diced components. After sieving, the components were left to stand in a constant temperature and humidity environment. (4) Suppression: Place a clamp at the bottom of the mold, and place a fiber-reinforced mesh on the clamp; add the cutting disc components according to the required proportion; rotate and flatten the cutting disc components; place the fiber-reinforced mesh on the cutting disc components after flattening; compact with a pressure of 7 MPa and hold for 10 s; place a clamp on the fiber-reinforced mesh; compact again with a pressure of 7 MPa and hold for 5 s to form the cutting disc molded sample; Hot pressing sintering: The cut disc sample was hot-pressed and sintered at a pressure of 10 MPa and a temperature of 130 ℃ for 1 h; hardening: The muffle furnace was preheated to 50 °C. The shaped cutting disc was then placed in the muffle furnace for high-temperature hardening. The high-temperature hardening temperature rise curve was as follows: holding at 50 °C for 2 hours, raising the temperature to 100 °C at a rate of 50 °C / h, holding at 100 °C for 1 hour, raising the temperature to 130 °C at a rate of 30 °C / h, holding at 130 °C for 2 hours, raising the temperature to 185 °C at a rate of 27.5 °C / h, holding at 185 °C for 3 hours, and then cooling with the furnace to 30 °C to produce a low-heat, high-efficiency rail cutting disc. The actual product is shown in the image. Figure 1 As shown.

[0029] Example 2 This embodiment provides a low-heat, high-efficiency rail cutting disc, the preparation method of which is as follows: (1) In this embodiment, the self-lubricating pore-forming packing is prepared using the method described in Example 1; (2) Premixed feed: Weigh 35 parts of brown fused alumina, 75 parts of zirconium fused alumina, and 10 parts of cubic boron nitride and mix them. The brown fused alumina should be 24 mesh, the zirconium fused alumina should be 16 mesh, and the cubic boron nitride should be 20 mesh. Feed the abrasive into a mixer and mix for 5 minutes to achieve full mixing and obtain the mixed abrasive. Weigh 6 parts of self-lubricating pore-forming filler; select 24-mesh carbonamide graphite molybdenum disulfide composite filler particles; add the carbonamide graphite molybdenum disulfide composite filler particles to the above mixed abrasive and mix thoroughly for 3 minutes to prepare the abrasive composition; Weigh 8 parts of phenolic resin powder, 3 parts of cryolite, 5.5 parts of pyrite, 2 parts of calcium oxide, and 10 parts of precipitated barium sulfate; select phenolic resin powder with a mesh size of 300 mesh and functional filler with a mesh size of 150 mesh; feed phenolic resin powder and functional filler into a drum mixer and mix thoroughly for 5 hours to prepare auxiliary material components. drying: The abrasive components and auxiliary components were dried in an oven at 60 ℃ for 24 h and then placed in a constant temperature and humidity environment. (3) Mixing: Phenolic resin liquid was selected as the wetting agent. Three parts of phenolic resin liquid were weighed and added to the abrasive component. The mixture was thoroughly mixed for 5 minutes. Then the auxiliary component was added and thoroughly mixed for 5 minutes to prepare the mixed component. Sieving: The mixed components were sieved through a 10-mesh sieve to obtain loose, diced components. After sieving, the components were left to stand in a constant temperature and humidity environment. (4) Suppression: Place a clamp at the bottom of the mold, and place a fiber-reinforced mesh on the clamp; add the cutting disc components according to the required proportion; rotate and flatten the cutting disc components; place the fiber-reinforced mesh on the cutting disc components after flattening; compact with a pressure of 7 MPa and hold for 10 s; place a clamp on the fiber-reinforced mesh; compact again with a pressure of 7 MPa and hold for 5 s to form the cutting disc molded sample; Hot pressing sintering: The cut disc sample was hot-pressed and sintered at a pressure of 10 MPa and a temperature of 130 ℃ for 1 h; hardening: The muffle furnace was preheated to 50 ℃. The shaped cutting disc was placed in the muffle furnace for high-temperature hardening. The high-temperature hardening temperature rise curve was as follows: hold at 50 ℃ for 2 h, raise the temperature to 100 ℃ at a rate of 50 ℃ / h, hold at 100 ℃ for 1 h, raise the temperature to 130 ℃ at a rate of 30 ℃ / h, hold at 130 ℃ for 2 h, raise the temperature to 185 ℃ at a rate of 27.5 ℃ / h, hold at 185 ℃ for 3 h, and then cool with the furnace to 30 ℃ to produce a low-heat, high-efficiency rail cutting disc.

[0030] Example 3 This embodiment provides a low-heat, high-efficiency rail cutting disc, the preparation method of which is as follows: (1) In this embodiment, the self-lubricating pore-forming packing is prepared using the method described in Example 1; (2) Premixed feed: Weigh 35 parts of brown fused alumina, 75 parts of zirconium fused alumina, and 10 parts of cubic boron nitride and mix them. The brown fused alumina should be 24 mesh, the zirconium fused alumina should be 16 mesh, and the cubic boron nitride should be 20 mesh. Feed the abrasive into a mixer and mix for 5 minutes to achieve full mixing and obtain the mixed abrasive. Weigh 4 portions of self-lubricating pore-forming filler; select 24-mesh carbonamide-graphite-molybdenum disulfide composite filler particles; add the carbonamide-graphite-molybdenum disulfide composite filler particles to the above-mentioned mixed abrasive and mix thoroughly for 3 minutes to prepare the abrasive composition; Weigh 8 parts of phenolic resin powder, 3 parts of cryolite, 5.5 parts of pyrite, 2 parts of calcium oxide, and 10 parts of precipitated barium sulfate; select phenolic resin powder with a mesh size of 300 mesh and functional filler with a mesh size of 150 mesh; feed phenolic resin powder and functional filler into a drum mixer and mix thoroughly for 5 hours to prepare auxiliary material components. drying: The abrasive components and auxiliary components were dried in an oven at 60 ℃ for 24 h and then placed in a constant temperature and humidity environment. (3) Mixing: Phenolic resin liquid was selected as the wetting agent. Three parts of phenolic resin liquid were weighed and added to the abrasive component. The mixture was thoroughly mixed for 5 minutes. Then the auxiliary component was added and thoroughly mixed for 5 minutes to prepare the mixed component. Sieving: The mixed components were sieved through a 10-mesh sieve to obtain loose, diced components. After sieving, the components were left to stand in a constant temperature and humidity environment. (4) Suppression: Place a clamp at the bottom of the mold, and place a fiber-reinforced mesh on the clamp; add the cutting disc components according to the required proportion; rotate and flatten the cutting disc components; place the fiber-reinforced mesh on the cutting disc components after flattening; compact with a pressure of 7 MPa and hold for 10 s; place a clamp on the fiber-reinforced mesh; compact again with a pressure of 7 MPa and hold for 5 s to form the cutting disc molded sample; Hot pressing sintering: The cut disc sample was hot-pressed and sintered at a pressure of 10 MPa and a temperature of 130 ℃ for 1 h; hardening: The muffle furnace was preheated to 50 ℃. The shaped cutting disc was placed in the muffle furnace for high-temperature hardening. The high-temperature hardening temperature rise curve was as follows: hold at 50 ℃ for 2 h, raise the temperature to 100 ℃ at a rate of 50 ℃ / h, hold at 100 ℃ for 1 h, raise the temperature to 130 ℃ at a rate of 30 ℃ / h, hold at 130 ℃ for 2 h, raise the temperature to 185 ℃ at a rate of 27.5 ℃ / h, hold at 185 ℃ for 3 h, and then cool with the furnace to 30 ℃ to produce a low-heat, high-efficiency rail cutting disc.

[0031] Example 4 The preparation method of the self-lubricating pore-forming filler for the cutting disc in this embodiment is the same as that in Example 1, except that the formulation ratio of the cutting disc is different.

[0032] The cutting disc in this embodiment includes, by weight, 40 parts brown corundum, 80 parts zirconium corundum, 15 parts cubic boron nitride, 20 parts phenolic resin powder, 5 parts phenolic resin liquid, 15 parts barium sulfate, 5 parts cryolite, 7 parts pyrite, 3 parts calcium oxide, and 8 parts self-lubricating pore-forming filler.

[0033] Example 5 The preparation method of the self-lubricating pore-forming filler for the cutting disc in this embodiment is the same as that in Example 3, except that the formulation ratio of the cutting disc is different.

[0034] The cutting disc in this embodiment includes, by weight, 30 parts brown corundum, 60 parts zirconium corundum, 10 parts cubic boron nitride, 10 parts phenolic resin powder, 3 parts phenolic resin liquid, 10 parts barium sulfate, 3 parts cryolite, 5 parts pyrite, 2 parts calcium oxide, and 4 parts self-lubricating pore-forming filler.

[0035] Comparative Example 1 To test the low-temperature, high-efficiency cutting performance of a low-heat, high-efficiency rail cutting disc for railway rail cutting, this comparative example was set up. The specific preparation methods of the comparison samples are as follows: (1) Premixed feed: Weigh 35 parts of brown fused alumina, 75 parts of zirconium fused alumina, and 10 parts of cubic boron nitride and mix them. The brown fused alumina should be 24 mesh, the zirconium fused alumina should be 16 mesh, and the cubic boron nitride should be 20 mesh. Feed the abrasive into a mixer and mix for 5 minutes to achieve full mixing and obtain the abrasive composition. Weigh 8 parts of phenolic resin powder, 3 parts of cryolite, 5.5 parts of pyrite, 2 parts of calcium oxide, and 10 parts of precipitated barium sulfate; select phenolic resin powder with a mesh size of 300 mesh and functional filler with a mesh size of 150 mesh; feed phenolic resin powder and functional filler into a drum mixer and mix thoroughly for 5 hours to prepare auxiliary material components. (2) Drying: The abrasive components and auxiliary components were dried in an oven at 60 ℃ for 24 h and then placed in a constant temperature and humidity environment. (3) Mixing: Phenolic resin liquid was selected as the wetting agent. Three parts of phenolic resin liquid were weighed and added to the abrasive component. The mixture was thoroughly mixed for 5 minutes. Then the auxiliary component was added and thoroughly mixed for 5 minutes to prepare the mixed component. Sieving: The mixed components were sieved through a 10-mesh sieve to obtain loose, diced components. After sieving, the components were left to stand in a constant temperature and humidity environment. (4) Suppression: Place a clamp at the bottom of the mold, and place a fiber-reinforced mesh on the clamp; add the cutting disc components according to the required proportion; rotate and flatten the cutting disc components; place the fiber-reinforced mesh on the cutting disc components after flattening; compact with a pressure of 7 MPa and hold for 10 s; place a clamp on the fiber-reinforced mesh; compact again with a pressure of 7 MPa and hold for 5 s to form the cutting disc molded sample; Hot pressing sintering: The cut disc sample was hot-pressed and sintered at a pressure of 10 MPa and a temperature of 130 ℃ for 1 h; hardening: The muffle furnace was preheated to 50 ℃. The shaped cutting disc was placed in the muffle furnace for high-temperature hardening. The high-temperature hardening temperature rise curve was as follows: hold at 50 ℃ for 2 h, raise the temperature to 100 ℃ at a rate of 50 ℃ / h, hold at 100 ℃ for 1 h, raise the temperature to 130 ℃ at a rate of 30 ℃ / h, hold at 130 ℃ for 2 h, raise the temperature to 185 ℃ at a rate of 27.5 ℃ / h, hold at 185 ℃ for 3 h, and then cool with the furnace to 30 ℃ to produce a rail cutting disc.

[0036] The cutting performance of the low-heat, high-efficiency rail cutting blade used for railway rail cutting in this embodiment was tested using a rail cutting machine. The cutting part was a 60 rail, and the material of the 60 rail was U71Mn rail steel. The cutting test started from the contact between the cutting blade and the 60 rail and ended from the complete separation of the 60 rail. The number of cuts, cutting time, cutting wear, perpendicularity, parallelism, flatness of the 60 rail cross section after cutting, and the burning condition of the rail after cutting were recorded.

[0037] The number of cuts refers to the number of times the cutting blade contacts the 60 rail during the cutting process; the cutting time is the time taken from the moment the cutting blade contacts the 60 rail until the 60 rail is completely cut and separated; the cutting loss refers to the reduction in the radius of the cutting blade after one rail cutting is completed.

[0038] Example 1: Comparison of loss before and after a single cut. Figure 2 As shown; the burn condition of the rail cut surface after a single cut in Example 1 and Comparative Example 1 is as follows. Figure 3 As shown; the perpendicularity of the rail cut surface after a single cut in Example 1 and Comparative Example 1 is as follows. Figure 4 As shown; the parallelism of the rail cut surfaces after a single cut in Example 1 and Comparative Example 1 is as follows. Figure 5 As shown; the flatness of the rail cut surface after a single cut in Example 1 and Comparative Example 1 is as follows. Figure 6 As shown.

[0039] In actual construction operations, the number of cuts is the main indicator for on-site testing. Usually, the rail is cut in 1 to 2 cuts, and it is best to cut in 1 cut to reduce the processing error caused by repeated cutting and affect the final overall processing quality. Therefore, achieving a 1-cut cut indicates that the cutting blade has good cutting performance, which is a key factor valued in on-site processing.

[0040] Depend on Figure 2 It can be seen that the cutting loss after a single cut in Example 1 is 10mm; Figure 3It can be seen that Example 1 can achieve a single cut, and the cut surface is bright and straight after a single cut, with clear texture and no obvious burn marks; the comparative example shows obvious burn marks on the cut surface after a single cut; Figure 4 , Figure 5 , Figure 6 It can be seen that after cutting, the parallelism, perpendicularity and flatness of Example 1 all meet the tolerance requirements of rail cutting and processing; however, after cutting, Comparative Example 1 fails to meet the maximum tolerance requirements of rail cutting and processing.

[0041] Under the same test conditions, the test results of Examples 1-3 and Comparative Example 1 are statistically shown in Table 1.

[0042] Table 1: Cutting performance test results of Examples 1-3 and Comparative Example 1

[0043] In the table, "-" indicates data that does not meet the parallelism test.

[0044] Table 1 shows the cutting performance of Examples 1-3 and Comparative Example 1 after a single cut. Examples 1-3 can complete the cutting of the 60-rail section in one cut. Compared with Comparative Example 1, the cutting time is shortened and the cutting loss is increased with the increase of the self-lubricating hole-forming material content. The perpendicularity, parallelism and flatness of the 60-rail section after cutting are improved.

[0045] This invention incorporates carbonamide-graphite-molybdenum disulfide composite filler particles into traditional cutting disc materials. Through the decomposition of the pore-forming material components, pores are formed. This porous structure effectively accommodates the high-temperature heat source generated at the cutting disc / rail contact interface. After detaching from the contact interface, the high-temperature heat source, the chips, is promptly expelled under the centrifugal force of the cutting disc. Simultaneously, the pores effectively increase the edge height of the abrasive within the cutting disc, enhancing its cutting performance. Meanwhile, the solid lubricant material is released through the porous structure at the cutting disc / rail contact surface, acting on the abrasive and rail surfaces to achieve lubrication at the abrasive-material contact interface, reducing frictional heat generation. The low-heat, high-efficiency rail cutting disc achieves low heat generation through two mechanisms: timely containment and removal of the high-temperature heat source (abrasive chips) and reduction of heat generation at the source (frictional heat generation).

[0046] In summary, the low-heat, high-efficiency rail cutting disc for railway rail cutting obtained by the preparation method described in this invention has excellent cutting performance, significantly shortens cutting time, reduces rail burns, meets the tolerance range required for rail cutting and processing, and can achieve low-heat, high-efficiency rail cutting.

[0047] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A low-heat, high-efficiency rail cutting blade, characterized in that, By weight, its raw materials include: 100-135 parts abrasive, 10-20 parts resin binder, 20-30 parts functional filler, 4-8 parts self-lubricating pore-forming material, and 3-5 parts wetting agent. The self-lubricating pore-forming material is a carbonamide-graphite-molybdenum disulfide composite filler particle; its components include a pore-forming component and a self-lubricating component; wherein, the pore-forming component is carbonamide, and the self-lubricating component is flake graphite powder and molybdenum disulfide powder; The preparation method of the carbonamide-graphite-molybdenum disulfide composite filler particles includes the following steps: Molten carbonamide is mixed with flake graphite powder and molybdenum disulfide powder to complete the adhesion and coating of flake graphite powder and molybdenum disulfide powder. After cooling and molding, it is crushed and sieved to obtain carbonamide-graphite-molybdenum disulfide composite filler particles. In the carbonamide-graphite-molybdenum disulfide composite filler particles, the proportions of each component by mass are 30-40 parts carbonamide, 6-9 parts graphite powder, and 4-6 parts molybdenum disulfide powder.

2. The low-heat, high-efficiency rail cutting disc according to claim 1, characterized in that: The abrasive comprises 30-40 parts brown fused alumina, 60-80 parts zirconium fused alumina, and 10-15 parts cubic boron nitride.

3. The low-heat, high-efficiency rail cutting disc according to claim 1, characterized in that: The resin adhesive includes phenolic resin powder.

4. The low-heat, high-efficiency rail cutting disc according to claim 1, characterized in that: The functional filler comprises 10-15 parts precipitated barium sulfate, 3-5 parts cryolite, 5-7 parts pyrite powder, and 2-3 parts calcium oxide.

5. The low-heat, high-efficiency rail cutting disc according to claim 1, characterized in that: The wetting agent includes phenolic resin liquid.

6. The low-heat, high-efficiency rail cutting disc according to claim 1, characterized in that: The resin adhesive has a particle size of 280-350 mesh, the abrasive has a particle size of 16-24 mesh, the self-lubricating pore-forming material has a particle size of 24-30 mesh, and the functional filler has a particle size of 100-150 mesh.

7. A method for preparing a low-heat, high-efficiency rail cutting disc as described in any one of claims 1 to 6, characterized in that, The steps include the following: (1) Weigh each raw material according to the proportion, mix brown corundum, zirconium corundum and cubic boron nitride to obtain mixed abrasive; add self-lubricating pore-forming material to the mixed abrasive and mix to obtain abrasive component; mix resin binder and functional filler to make auxiliary component; dry the abrasive component and auxiliary component and place them in a constant temperature and humidity environment. (2) Add the wetting agent to the abrasive component and mix. After the mixture is completed, add the auxiliary component and mix to form a mixed component. The mixed component is sieved to obtain a loose cutting disc component. After sieving, it is left to stand in a constant temperature and humidity environment. (3) The cutting disc components are pressed with fiber reinforced mesh to form a cutting disc molded sample; the cutting disc molded sample is hot-pressed, sintered and hardened to obtain a low-heat, high-efficiency rail cutting disc.

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