Grinding wheel and production method and application thereof

Abstract

The invention provides a grinding wheel and a production method and application thereof. The grinding wheel comprises the following raw materials in parts by weight: 15-35 parts of a composite adhesive, 70-100 parts of a grinding material, 5-15 parts of a self-adaptive friction regulator and 6-10 parts of a wetting agent. The grinding wheel is high in compressive strength, good in self-sharpening performance, low in average friction coefficient of a grinding pair interface when used for grinding, high in grinding amount and large in grinding ratio. The production method of the grinding wheel comprises the following steps: (1) material mixing: firstly mixing the grinding material, the self-adaptive friction regulator and the wetting agent, and then mixing the mixed wet material with the composite adhesive; and (2) forming: putting the mixed material obtained in the step (1) into a forming mold, carrying out compression molding, demolding and then carrying out curing treatment. The production method is simple, the defects of the grinding wheel can be effectively reduced, the compressive strength of the grinding wheel is improved, and the service life of the grinding wheel is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of grinding wheels, and in particular relates to a grinding wheel and a production method and application thereof. Background Art

[0002] Grinding wheels are also called bonded abrasives. Grinding wheels are bonded abrasives that are bonded by adhesives into a certain shape (mostly round with a through hole in the center) and have a certain strength. Grinding wheels are generally composed of abrasives, adhesives, and pores. These three parts are often called the three elements of bonded abrasives. According to the different classifications of adhesives, common ones are ceramic grinding wheels, resin grinding wheels, and rubber grinding wheels. Grinding wheels are the most widely used and widely used abrasives. When used, they rotate at high speeds and can be used for rough grinding, semi-finishing grinding, and fine grinding of the outer circle, inner circle, plane, and various surfaces of metal or non-metal workpieces, as well as grooving and cutting.

[0003] However, existing grinding wheels generally have disadvantages such as low heat resistance, average strength, and low durability. Moreover, when the grinding wheel is running at high speed, the temperature at the friction point between the grinding wheel and the workpiece is high, thus affecting the quality of the workpiece. Summary of the invention

[0004] In view of the deficiencies of the prior art, the object of the present invention is to provide a grinding wheel and a production method and application thereof; the grinding wheel of the present invention has high compressive strength and good self-sharpening property, and when used for grinding, the average friction coefficient of the grinding pair interface is low, the grinding amount is high, and the grinding ratio is large. The production method of the present invention is simple, and can effectively reduce the defects of the grinding wheel, improve the compressive strength of the grinding wheel, and extend the service life of the grinding wheel.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] In the first aspect, the present invention provides a grinding wheel, wherein the raw materials of the grinding wheel include, by weight: 15 to 35 parts of a composite adhesive, 70 to 100 parts of abrasive, 5 to 15 parts of an adaptive friction modifier, and 6 to 10 parts of a wetting agent; the raw materials of the adaptive friction modifier include, by weight: 30 to 55 parts of a metal adhesive, 3 to 10 parts of a self-lubricating filler, and 35 to 60 parts of a spatially dispersed filler.

[0007] In some embodiments of the present invention, the metal adhesive is any one of copper powder and iron powder or a mixture of the two; preferably, the particle size of the metal adhesive is above 200 mesh, preferably 220-300 mesh.

[0008] In some embodiments of the present invention, the self-lubricating filler includes any one of graphite powder, molybdenum disulfide powder, fluorite powder, tungsten sulfide powder, etc., or a mixture of two or more thereof; preferably, the particle size of the self-lubricating filler is above 100 mesh, preferably 120-180 mesh.

[0009] In some embodiments of the present invention, the spatial dispersion filler includes fibers and spatial fillers; preferably, the spatial dispersion filler includes 10 to 25 parts of fibers and 25 to 55 parts of spatial fillers by weight.

[0010] In some embodiments of the present invention, the fiber is any one of basalt fiber, copper fiber, steel fiber, glass fiber, etc., or a mixture of two or more thereof; preferably, the fiber has a diameter of 10 to 50 μm and a length of 0.8 to 3 mm.

[0011] In some embodiments of the present invention, the space filler is any one of chromite powder, feldspar powder, alumina, silica, barium sulfate, etc., or a mixture of two or more thereof; preferably, the particle size of the space filler is above 200 mesh, preferably 200-260 mesh.

[0012] In some embodiments of the present invention, the adaptive friction modifier is prepared by a method comprising the following steps:

[0013] 1) Mixing: Mix the metal adhesive, self-lubricating filler and space dispersion filler;

[0014] 2) Blank forming: placing the mixed material obtained in step 1) in a mold and pressing it to obtain a blank;

[0015] 3) Sintering: Sintering the blank obtained in step 2) at high temperature;

[0016] 4) Granulation: The product obtained by high temperature sintering in step 3) is crushed and sieved to obtain the adaptive friction modifier.

[0017] In some embodiments of the present invention, step 1) is performed in a ball mill; more preferably, the conditions for mixing in the ball mill include: a ball mill speed of 300 to 450 rpm, a ball-to-material ratio of (1 to 3):1, and a mixing time of 10 to 20 h.

[0018] In some embodiments of the present invention, the raw materials used for mixing in step 1) are dry raw materials, preferably raw materials that have been dried; more preferably, the drying is carried out at 120-150° C. for 20-30 hours.

[0019] In some embodiments of the present invention, in step 2), the forming pressure is 120 to 450 MPa, preferably 220 to 350 MPa; the holding time is 1 to 3 hours, preferably 1 to 2 hours.

[0020] In some embodiments of the present invention, in step 3), the sintering temperature is 800-1200° C., the sintering time is 10-20 h, and the sintering pressure is 1.5-4 MPa.

[0021] In some embodiments of the present invention, the crushing in step 4) is performed in a jaw crusher or a single-cylinder cone crusher.

[0022] In some embodiments of the present invention, the screening in step 4) is first through a F12-F22 mesh sieve, the undersize material is then passed through a F46-F80 mesh sieve, and then the oversize material is recovered.

[0023] In some embodiments of the present invention, the F12-F22 mesh sieve means that the sieve can be selected from any one of the F12 mesh sieve, the F14 mesh sieve, the F16 mesh sieve, the F20 mesh sieve, the F22 mesh sieve and the like.

[0024] In some embodiments of the present invention, F46-F80 mesh screen means that the mesh screen can be selected from any one of F46 mesh screen, F54 mesh screen, F60 mesh screen, F70 mesh screen, F80 mesh screen and the like.

[0025] In some embodiments of the present invention, the screening is to first pass through an F16 mesh screen, obtain the undersize material, then pass through an F60 mesh screen, and then recover the oversize material.

[0026] In some embodiments of the present invention, the particle size of the adaptive friction modifier is 0.15 to 1.5 mm, preferably 0.25 to 1.0 mm.

[0027] In some embodiments of the present invention, the composite adhesive comprises an organic component and an inorganic component; preferably, the composite adhesive comprises 50 to 66 parts of the organic component and 40 to 65 parts of the inorganic component by weight.

[0028] In some embodiments of the present invention, the organic component includes a modified phenolic resin; more preferably, the modified phenolic resin is selected from any one or more of epoxy-modified phenolic resin and silicone-modified phenolic resin; more preferably, it is selected from silicone-modified and epoxy-modified phenolic resins.

[0029] In the present invention, the epoxy-modified phenolic resin has a strong bonding ability, can reduce the resin curing shrinkage, and improve the resin curing toughness and alkali resistance; thus, the impact resistance, alkali resistance and durability of the grinding wheel can be improved.

[0030] In the present invention, the organosilicon-modified phenolic resin has strong heat resistance and water resistance, and can improve the durability and anti-attenuation ability of the grinding wheel.

[0031] In some embodiments of the present invention, the inorganic component includes any one or a mixture of two or more of barium sulfate, pyrite, chopped fibers, cryolite, sapphire whiskers, etc.; preferably, the chopped fibers are any one or a mixture of two or more of glass fibers, basalt fibers, aramid fibers, etc.

[0032] In some embodiments of the present invention, the inorganic component includes at least sapphire whiskers.

[0033] In the present invention, a proper amount of sapphire whiskers is added to the composite adhesive, and the sapphire whiskers can play a micro-connection and bridging role in the grinding wheel, which is beneficial to improving the overall strength of the grinding wheel.

[0034] In some embodiments of the present invention, the composite adhesive comprises, by weight, 50 to 66 parts of modified phenolic resin, 10 to 15 parts of barium sulfate, 13 to 18 parts of pyrite, 8 to 13 parts of chopped fibers, 8 to 15 parts of cryolite, and 2 to 4 parts of sapphire whiskers.

[0035] In some embodiments of the present invention, the particle size of the modified phenolic resin is above 1000 mesh, preferably 1000-1200 mesh.

[0036] In some embodiments of the present invention, the particle size of the barium sulfate, pyrite, and cryolite is above 325 mesh, preferably 325-400 mesh.

[0037] In some embodiments of the present invention, the sapphire whiskers are α-aluminum oxide whiskers with a whisker diameter of 0.1 to 1 μm and a whisker length of 100 to 500 μm; preferably, the whisker diameter is 0.1 to 0.4 μm and the whisker length is 100 to 300 μm.

[0038] In some embodiments of the present invention, the chopped fibers have a single filament diameter of 5 to 10 μm and a length of 1 to 4 mm.

[0039] In some embodiments of the present invention, the wetting agent is furfural.

[0040] In some embodiments of the present invention, the abrasive is a composition including α-Al2O3&ZrO2 eutectic corundum, coated brown corundum, and white corundum.

[0041] In some embodiments of the present invention, the abrasive comprises, by weight, 30 to 45 parts of α-Al2O3&ZrO2 eutectic corundum, 35 to 50 parts of coated brown corundum, and 10 to 15 parts of white corundum; preferably, it comprises 30 to 36 parts of α-Al2O3&ZrO2 eutectic corundum, 42 to 50 parts of coated brown corundum, and 12 to 15 parts of white corundum.

[0042] In some embodiments of the present invention, the particle size of the α-Al2O3&ZrO2 eutectic corundum is F14-F16, the particle size of the coated brown corundum is F20-F24, and the particle size of the white corundum is F24-F30.

[0043] In some embodiments of the present invention, the particle size of the α-Al2O3&ZrO2 eutectic corundum is F14-F16, which means that the α-Al2O3&ZrO2 eutectic corundum can pass through the F14 mesh sieve, but cannot pass through the F16 mesh sieve.

[0044] In some embodiments of the present invention, the particle size of the coated brown corundum is F20-F24, which means that the coated brown corundum can pass through the F20 mesh sieve, but cannot pass through the F24 mesh sieve.

[0045] In some embodiments of the present invention, the particle size of the white corundum is F20-F24, which means that the white corundum can pass through the F24 mesh sieve, but cannot pass through the F30 mesh sieve.

[0046] In a second aspect, the present invention provides a method for producing the grinding wheel according to the first aspect, the production method comprising the following steps:

[0047] (1) Mixing: first mix the abrasive, adaptive friction modifier, and wetting agent, and then mix the mixed wet material with the composite adhesive;

[0048] (2) Molding: The mixed material obtained in step (1) is placed in a molding mold for compression molding, and then subjected to curing treatment after demoulding.

[0049] In some embodiments of the present invention, the mixing in step (1) is carried out in a double-pot countercurrent mixer.

[0050] In some embodiments of the present invention, the step (2) of placing the mixed material obtained in step (1) in a molding die for compression molding includes: controlling the temperature of the molding die to (120-150)°C±5°C and keeping it warm for 4-6 minutes, then pressurizing it to 8-15MPa and maintaining the pressure for 3-5 minutes and then releasing the pressure for 50-70 seconds; repeating the pressurization and pressure relief operations 3-5 times.

[0051] In some embodiments of the present invention, the step (2) of placing the mixed material obtained in step (1) in a molding die for compression molding includes: controlling the temperature of the molding die to (120-150)°C±5°C for 4-6 minutes, then pressurizing to 8-15MPa for 9-25 minutes and then releasing the pressure.

[0052] In some embodiments of the present invention, the depressurization refers to removing the pressurization, that is, the mold is at normal pressure at this time.

[0053] In some embodiments of the present invention, the curing treatment in step (2) includes a staged heating process, preferably a 3-5 stage heating process; preferably, any one or more of the heating rate, insulation temperature and cooling rate are precisely controlled during the curing process; more preferably, the heating rate is precisely controlled to be between 1 and 3°C / min, the cooling rate is between 1 and 3°C / min, and the insulation temperature fluctuation is ≤5°C during the curing process.

[0054] In some embodiments of the present invention, the specific process of curing treatment in step (2) includes: first keeping warm at (50-60)°C±5°C for 3-5h, then heating to 120-150°C at a heating rate of 1-3°C / min, then keeping warm at the temperature±5°C for 6-8h, then heating to 185-195°C at a heating rate of 1-2°C / min, then keeping warm at the temperature±2°C for 15-27h, and finally cooling to 15-35°C at a cooling rate of 1-3°C / min. In this process, the free water in the green body to be solidified can be removed by keeping the temperature at (50-60)℃±5℃ for 3-5h; the viscosity of the organic component can be adjusted by heating the green body to 120-150℃ at a heating rate of 1-3℃ / min; the microcracks and abrasive interface defects in the green body can be automatically healed by keeping the temperature at (120-150)℃±5℃ for 6-8h; the viscosity of the organic component can be further adjusted by heating the green body to 185-195℃ at a heating rate of 1-2℃ / min; the cross-linking degree of the organic component in the grinding wheel can be adjusted by keeping the temperature at (185-195)℃±2℃ for 15-27h, thereby controlling the strength and toughness of the grinding wheel; the organic component in the grinding wheel can be highly coordinated in thermal expansion and contraction by cooling the green body to 15-35℃ at a cooling rate of 1-3℃ / min, thereby reducing the defects of the grinding wheel caused by thermal stress.

[0055] In some embodiments of the present invention, the production method further includes performing anhydration treatment on the raw materials before mixing; preferably, the anhydration treatment on the raw materials is drying the raw materials to remove free water molecules; more preferably, the anhydration treatment on the raw materials includes: keeping the organic components of the composite adhesive at a constant temperature of (50-60)°C±2°C for 10-20 hours, and / or, keeping the inorganic components of the composite adhesive at a constant temperature of (60-70)°C±2°C for 7-12 hours, and / or, keeping the abrasive at a constant temperature of 120-150°C for 20-30 hours, and / or, keeping the adaptive friction modifier at a constant temperature of 120-150°C for 20-30 hours.

[0056] In some embodiments of the present invention, step (1) further comprises screening the material obtained by mixing the mixed wet material and the composite adhesive, preferably first screening the material through a F30-F40 mesh sieve, obtaining the material on the sieve and then screening the material under the sieve through a F8-F12 mesh sieve to recover the material under the sieve.

[0057] In some embodiments of the present invention, F30-F40 mesh sieve means that the sieve can be selected from any one of F30 mesh sieve, F32 mesh sieve, F34 mesh sieve, F36 mesh sieve, F38 mesh sieve, F40 mesh sieve and the like.

[0058] In some embodiments of the present invention, the F8-F12 mesh screen means that the screen can be selected from any one of the F8 mesh screen, the F10 mesh screen, the F12 mesh screen and the like.

[0059] In some embodiments of the present invention, the method for producing a grinding wheel comprises the following steps:

[0060] (1) Anhydrous treatment of raw materials:

[0061] (1-1) Keeping the organic components of the composite adhesive at a constant temperature of (50-60)°C ± 2°C for 10-20 hours;

[0062] (1-2) keeping the inorganic components of the composite adhesive at a constant temperature of (60-70)°C ± 2°C for 7-12 hours;

[0063] (1-3) Keeping the abrasive at a constant temperature of 120 to 150°C for 20 to 30 hours;

[0064] (1-4) Keep the adaptive friction modifier at a constant temperature of 120 to 150°C for 20 to 30 hours.

[0065] (2) Mixing:

[0066] (2-1) placing the inorganic components of the composite adhesive treated in step (1-2) in a ball mill, and blending for 40 to 80 minutes at a ball mill speed of 400 to 500 rpm and a ball-to-material ratio of (2 to 3):1;

[0067] (2-2) adding the organic component of the composite adhesive treated in step (1-1) to the ball mill in step (2-1), and continuing to blend for 4 to 8 minutes at a ball mill speed of 400 to 500 rpm and a ball-to-material ratio of (1 to 2):1 to obtain a composite adhesive;

[0068] (2-3) placing the abrasive in the upper pot of a double pot countercurrent mixer, stirring for 1 to 3 minutes with the upper pot rotating at a clockwise speed of 50 to 70 rpm and the material fork rotating at a counterclockwise speed of 20 to 30 rpm to fully mix the abrasive to obtain a mixed abrasive;

[0069] (2-4) adding the adaptive friction modifier to the upper pot of the double pot countercurrent mixer in step (2-3), stirring for 1 to 2 minutes with the upper pot rotating clockwise at 50 to 70 rpm and the material fork rotating counterclockwise at 20 to 30 rpm to uniformly mix the mixed abrasive;

[0070] (2-5) adding a wetting agent to the upper pot of the double pot countercurrent mixer in step (2-4), stirring for 1 to 2 minutes with the upper pot rotating clockwise at 50 to 70 rpm and the material fork rotating counterclockwise at 20 to 30 rpm to obtain a mixed wet material, and transferring the mixed wet material to the lower pot of the double pot countercurrent mixer;

[0071] (2-6) adding the composite adhesive obtained in step (2-2) to the lower pot of the double pot countercurrent mixer in step (2-4), stirring for 3 to 5 minutes with the lower pot rotating at a clockwise speed of 50 to 70 rpm and the material fork rotating at a counterclockwise speed of 20 to 30 rpm;

[0072] (2-7) The mixed material obtained in step (2-6) is first passed through a F30-F40 mesh sieve, the material on the sieve is obtained and then passed through a F8-F12 mesh sieve, and the material under the sieve is recovered to obtain the grinding wheel molding material.

[0073] (3) Molding:

[0074] (3-1) placing the grinding wheel material to be molded obtained in step (2-7) in a molding mold, controlling the molding mold temperature to (120-150)°C±5°C for 5 minutes, then starting to pressurize to 8-15 MPa, maintaining the pressure for 3-5 minutes, and then releasing the pressure for 50-70 seconds; repeating the pressurization and pressure release operations 3-5 times; and then demolding to obtain a grinding wheel blank;

[0075] (3-2) The grinding wheel blank obtained in step (3-1) is placed in a blast drying oven for curing treatment, and the specific process of the curing treatment includes: first keeping it at (50-60)°C±5°C for 3-5h, then heating it to 120-150°C at a heating rate of 1-3°C / min, then keeping it at this temperature±5°C for 6-8h, then heating it to 185-195°C at a heating rate of 1-2°C / min, then keeping it at this temperature±2°C for 15-27h, and finally cooling it to 15-35°C at a cooling rate of 1-3°C / min.

[0076] In a third aspect, the present invention provides the use of the grinding wheel described in the first aspect and / or the grinding wheel produced by the production method described in the second aspect in rail grinding.

[0077] The beneficial effects of the present invention are as follows:

[0078] The present invention adds an adaptive friction regulator to the grinding wheel. The adaptive friction regulator is evenly distributed in the three-dimensional geometric space of the grinding wheel. During the grinding process, it can be broken or worn and dispersed on the workpiece / grinding wheel interface to play a lubricating role and reduce the grinding temperature. At the same time, the broken adaptive friction regulator forms pores on the surface of the grinding wheel, which can increase the abrasive edge height, improve the self-sharpening property of the grinding wheel, and improve the grinding efficiency.

[0079] The production method of the present invention is simple, and when mixing, the abrasive and the adaptive friction modifier are first mixed and then the composite binder is added, which can effectively improve the uniformity of the distribution of the adaptive friction modifier in the grinding wheel; moreover, the addition of a wetting agent to mix with the abrasive and the adaptive friction modifier can improve the wettability of the surface of the abrasive and adaptive friction modifier particles, thereby improving the bonding strength between them and the composite binder and improving the compressive strength of the grinding wheel. Furthermore, the present invention proposes to accurately control the heating rate, the insulation temperature, and the cooling rate during the curing process, and through precise temperature control and segmented heating processes, the crosslinking degree of the organic components in the composite binder can be effectively adjusted, thereby regulating the toughness and internal stress of the grinding wheel, and further improving the strength of the grinding wheel. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] Figure 1 The burn morphology of the rail surface after the rail is ground using the grinding wheel of Example 1 of the present invention and the grinding wheel of Comparative Example 1 respectively is shown.

[0081] Figure 2 The metallographic morphology of the cross section of the rail after the rail is ground using the grinding wheel of Example 1 of the present invention and the grinding wheel of Comparative Example 1 respectively is shown.

[0082] Figure 3 The clogging of the grinding wheel surface after the rails are ground using the grinding wheel of Example 1 of the present invention and the grinding wheel of Comparative Example 1 respectively is shown.

[0083] Figure 4 The figures show the strip-shaped grinding chip morphology formed by continuous cutting of the grinding wheels after the rails are ground using the grinding wheels of Example 1 of the present invention and the grinding wheels of Comparative Example 1, respectively. DETAILED DESCRIPTION

[0084] The following examples further illustrate the technology of the present invention. These examples are for illustration and example of the present invention and are not intended to limit the scope of the present invention in any form.

[0085] The adaptive friction modifiers used in the following examples were prepared in the following manner:

[0086] The raw materials of the adaptive friction modifier include, by weight: 35 parts of copper powder, 4 parts of graphite powder, 3 parts of fluorite powder, 3 parts of basalt fiber, 12 parts of copper fiber, 8 parts of chromite powder, 17 parts of alumina powder, and 8 parts of barium sulfate powder.

[0087] Among them, copper powder is 300 mesh, graphite powder is 120 mesh, fluorite powder is 160 mesh, chromite powder is 200 mesh, alumina powder is 200 mesh, and barium sulfate powder is 260 mesh.

[0088] The diameter of the basalt fiber and the copper fiber is 10 to 20 μm, and the length is 0.8 to 1.5 mm.

[0089] The method for preparing the adaptive friction modifier comprises the following steps:

[0090] 1) Raw material pretreatment: Place each raw material in a vacuum drying oven at 150°C for 25 hours.

[0091] 2) Mixing: The raw material pretreated in step 1) is placed in a ball mill and mixed for 15 hours at a ball mill speed of 400 rpm and a ball-to-material ratio of 2:1.

[0092] 3) Compression molding: The mixed material obtained in step 2) is placed in a mold, and after compression molding at a molding pressure of 240 MPa and a holding time of 1 h, the mold is demolded to obtain a blank.

[0093] 4) Sintering: The blank obtained in step 3) is sintered at 800° C. and 1 MPa pressure for 20 h, and then cooled in the furnace to obtain a block-shaped adaptive friction modifier material.

[0094] 5) Granulation: The block friction modifier material is crushed by a jaw crusher, and then the crushed material is passed through an F16 mesh screen, the undersize material is passed through an F60 mesh screen, and finally the oversize material is recovered to obtain an adaptive friction modifier with uniform particle size.

[0095] Other raw materials used in the following examples and comparative examples are all commercially available products.

[0096] Example 1

[0097] A grinding wheel comprises raw materials, measured by weight, of which: 28 parts of a composite adhesive, 90 parts of abrasives, 10 parts of an adaptive friction regulator, and 7 parts of a wetting agent.

[0098] The composite adhesive comprises, by weight, 60 parts of modified phenolic resin, 10 parts of barium sulfate, 15 parts of pyrite, 8 parts of glass fiber, 15 parts of cryolite, and 4 parts of sapphire whiskers.

[0099] The modified phenolic resin is a silicone-modified and epoxy-modified phenolic resin with a particle size of 1200 meshes.

[0100] The particle size of the barium sulfate, pyrite and cryolite is 325 mesh.

[0101] The sapphire whisker is an α-aluminum oxide whisker with a whisker diameter of 0.1 to 0.4 μm and a whisker length of 100 to 300 μm.

[0102] The monofilament diameter of the glass fiber is 5 to 10 μm and the length is 1 to 4 mm.

[0103] The abrasive comprises 30 parts of α-Al2O3&ZrO2 eutectic corundum, 45 parts of coated brown corundum and 15 parts of white corundum by weight; wherein the particle size of the α-Al2O3&ZrO2 eutectic corundum is F14-F16, the particle size of the coated brown corundum is F20-F24, and the particle size of the white corundum is F24-F30.

[0104] The wetting agent is furfural.

[0105] The preparation method of the grinding wheel comprises the following steps:

[0106] (1) Anhydrous treatment of raw materials:

[0107] (1-1) placing the modified phenolic resin in a vacuum drying oven at 60°C ± 2°C for 20 hours;

[0108] (1-2) Place barium sulfate, pyrite, chopped fibers, cryolite, and sapphire whiskers in a vacuum drying oven at 65°C ± 2°C for 10 h;

[0109] (1-3) placing the abrasive in a vacuum drying oven at 120°C for 20 hours;

[0110] (1-4) The adaptive friction modifier was placed in a vacuum drying oven at 120°C for 20 hours.

[0111] (2) Mixing:

[0112] (2-1) placing the barium sulfate, pyrite, chopped fibers, cryolite, and sapphire whiskers treated in step (1-2) in a planetary ball mill, and blending for 60 minutes at a ball mill speed of 450 rpm and a ball-to-material ratio of 2:1;

[0113] (2-2) adding the modified phenolic resin treated in step (1-1) into the planetary ball mill of step (2-1), and continuing to blend for 6 minutes at a ball mill speed of 450 rpm and a ball-to-material ratio of 1:1 to obtain a composite adhesive;

[0114] (2-3) placing the abrasive treated in step (1-3) in the upper pot of a double-pot countercurrent mixer, stirring for 2 min with the upper pot rotating clockwise at 60 rpm and the material fork rotating counterclockwise at 25 rpm to fully mix the abrasive to obtain a mixed abrasive;

[0115] (2-4) adding the adaptive friction modifier treated in step (1-4) to the upper pot of the double-pot countercurrent mixer in step (2-3), stirring for 1.5 minutes with the upper pot rotating clockwise at 60 rpm and the material fork rotating counterclockwise at 25 rpm to uniformly mix the mixed abrasive;

[0116] (2-5) Add the wetting agent to the upper pot of the double pot countercurrent mixer in step (2-4), continue stirring for 1 min with the upper pot rotating clockwise at 60 rpm and the material fork rotating counterclockwise at 25 rpm to obtain a mixed wet material, and transfer the mixed wet material to the lower pot of the double pot countercurrent mixer;

[0117] (2-6) Add the composite adhesive obtained in step (2-2) to the lower pot of the double-pot countercurrent mixer in step (2-4), and continue stirring for 4 minutes with the lower pot rotating clockwise at 60 rpm and the material fork rotating counterclockwise at 25 rpm;

[0118] (2-7) The mixed material obtained in step (2-6) is first passed through an F34 mesh sieve, the material on the sieve is obtained and then passed through an F10 mesh sieve, and the material under the sieve is recovered to obtain the grinding wheel molding material.

[0119] (3) Molding:

[0120] (3-1) placing the grinding wheel material to be molded obtained in step (2-7) in a molding mold, controlling the molding mold temperature to 120°C±5°C for 5 minutes, then starting to pressurize to 12 MPa and hold the pressure for 4 minutes, then releasing the pressure for 1 minute; then pressurizing to 12 MPa and holding the pressure for 4 minutes, then releasing the pressure for 1 minute; then pressurizing to 12 MPa and holding the pressure for 4 minutes, then releasing the pressure for 1 minute; then pressurizing to 12 MPa and holding the pressure for 4 minutes, then releasing the pressure for 1 minute; then pressurizing to 12 MPa and holding the pressure for 4 minutes, then releasing the pressure for 1 minute; then pressurizing to 12 MPa and holding the pressure for 4 minutes, then releasing the pressure for 1 minute; then demolding to obtain a grinding wheel blank;

[0121] (3-2) The grinding wheel blank obtained in step (3-1) is placed in a blast drying oven for curing treatment, and the curing treatment adopts a three-stage heating and precise temperature control process; the specific process of the curing treatment is: first keep it at 60℃±5℃ for 5h, then heat it to 125℃ at a heating rate of 1℃ / min, then keep it at 125℃±5℃ for 8h, then heat it to 190℃ at a heating rate of 1℃ / min, then keep it at 190℃±2℃ for 20h, and finally cool it to 20℃ at a cooling rate of 3℃ / min.

[0122] Example 2

[0123] The raw materials and preparation method of the grinding wheel are substantially the same as those of Example 1, except that the weight portion of the sapphire whisker in the composite adhesive is 1 part.

[0124] Example 3

[0125] The raw materials and preparation method of the grinding wheel are substantially the same as those of Example 1, except that the weight portion of the sapphire whisker in the composite adhesive is 0 parts.

[0126] Example 4

[0127] The raw materials and preparation method of the grinding wheel are substantially the same as those of Example 1, except that the weight portion of the adaptive friction modifier is 5 parts.

[0128] Example 5

[0129] The raw materials and preparation method of the grinding wheel are substantially the same as those of Example 1, except that the weight portion of the adaptive friction modifier is 15 parts.

[0130] Example 6

[0131] The raw materials and preparation method of the grinding wheel are basically the same as those in Example 1, except that the curing treatment in step (3-2) adopts a three-stage heating process, but no precise temperature control is performed (the heating rate and the cooling rate are not controlled). The specific treatment is: first keep warm at 55°C±5°C for 1.5 hours, then heat to 125°C and keep warm at 125°C±5°C for 2.5 hours, then heat to 180°C and keep warm at 180°C±5°C for 24 hours, and finally cool with the furnace.

[0132] Example 7

[0133] The raw materials and preparation method of the grinding wheel are basically the same as those in Example 1, except that step (3-1) is: placing the grinding wheel material to be molded obtained in step (2-7) in a molding mold, controlling the temperature of the molding mold to be 120°C±5°C for 5 minutes, then pressurizing to 12MPa for 20 minutes, and then releasing the pressure; finally demolding to obtain a grinding wheel blank.

[0134] Comparative Example 1

[0135] The raw materials and preparation method of the grinding wheel are substantially the same as those of Example 1, except that the weight portion of the adaptive friction modifier is 0 part.

[0136] Comparative Example 2

[0137] The raw materials and preparation method of the grinding wheel are substantially the same as those of Example 1, except that the adaptive friction modifier is replaced by graphite powder with a particle size of F16 to F60 mesh.

[0138] The grinding wheels produced in the above Examples 1 to 7 and Comparative Examples 1 to 2 were subjected to compressive strength tests and grinding performance tests. The results are shown in Table 1.

[0139] Table 1 Grinding wheel performance test results

[0140]

[0141]

[0142] In addition, the rails were ground using the grinding wheels produced in Example 1 of the present invention and Comparative Example 1, and then the rails and the grinding wheels were observed; wherein the surface morphology of the rails after grinding is as follows: Figure 1 As shown in Figure 2, the metallographic structure of the rail section is as follows: Figure 2 As shown, the grinding wheel surface is blocked as Figure 3 As shown; the strip-shaped grinding chips formed by continuous cutting of the grinding wheel are as follows Figure 4 shown.

[0143] It should be noted that the above-described embodiments are only used to explain the present invention and do not constitute any limitation of the present invention. The embodiments describe the present invention and it should be understood that the words used therein are descriptive and explanatory words, rather than limiting words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention.

Claims

1. A grinding wheel, characterized in that: The raw materials of the grinding wheel include, by weight: 15 to 35 parts of composite adhesive, 70 to 100 parts of abrasive, 5 to 15 parts of adaptive friction regulator, and 6 to 10 parts of wetting agent; the raw materials of the adaptive friction regulator include, by weight: 30 to 55 parts of metal adhesive, 3 to 10 parts of self-lubricating filler, and 35 to 60 parts of spatial dispersion filler.

2. The grinding wheel according to claim 1, characterized in that The metal adhesive is any one of copper powder and iron powder or a mixture of the two; preferably, the particle size of the metal adhesive is above 200 mesh, preferably 220-300 mesh; And / or, the self-lubricating filler comprises any one of graphite powder, molybdenum disulfide powder, fluorite powder, tungsten sulfide powder, or a mixture of two or more thereof; preferably, the particle size of the self-lubricating filler is above 100 mesh, preferably 120-180 mesh; And / or, the spatial dispersion filler comprises fibers and spatial fillers; preferably, the spatial dispersion filler comprises 10 to 25 parts of fibers and 25 to 55 parts of spatial fillers by weight; more preferably, The fiber is any one of basalt fiber, copper fiber, steel fiber, glass fiber, or a mixture of two or more thereof; preferably, the fiber has a diameter of 10 to 50 μm and a length of 0.8 to 3 mm; and / or The space filler is any one of chromite powder, feldspar powder, alumina, silicon dioxide, barium sulfate, or a mixture of two or more thereof; preferably, the particle size of the space filler is above 200 mesh, preferably 200-260 mesh.

3. The grinding wheel according to claim 1 or 2, characterized in that: The adaptive friction modifier is prepared by a method comprising the following steps: 1) Mixing: Mix the metal adhesive, self-lubricating filler and space dispersion filler; 2) Blank forming: placing the mixed material obtained in step 1) in a mold and pressing it to obtain a blank; 3) Sintering: Sintering the blank obtained in step 2) at high temperature; 4) Granulation: crushing and sieving the product obtained by high temperature sintering in step 3) to obtain an adaptive friction modifier; Preferably, the step 1) is carried out in a ball mill; more preferably, the conditions for mixing in the ball mill include: a ball mill speed of 300 to 450 rpm, a ball-to-material ratio of (1 to 3): 1, and a mixing time of 10 to 20 hours; Preferably, the raw material used for mixing in step 1) is a dried raw material, preferably a raw material that has been dried; more preferably, the drying is performed at 120 to 150° C. for 20 to 30 hours; Preferably, in step 2), the forming pressure is 120-450 MPa, preferably 220-350 MPa; the holding time is 1-3 h, preferably 1-2 h; Preferably, in step 3), the sintering temperature is 800-1200° C., the sintering time is 10-20 h, and the sintering pressure is 1.5-4 MPa; Preferably, the crushing in step 4) is carried out in a jaw crusher or a single-cylinder cone crusher; Preferably, the screening in step 4) is first through a F12-F22 mesh sieve, the undersize material is then screened through a F46-F80 mesh sieve, and then the oversize material is recovered.

4. The grinding wheel according to any one of claims 1 to 3, characterized in that The composite adhesive comprises an organic component and an inorganic component; Preferably, the organic component comprises a modified phenolic resin; more preferably, the modified phenolic resin is selected from any one or more of epoxy-modified phenolic resin and organosilicon-modified phenolic resin; more preferably, it is selected from organosilicon-modified and epoxy-modified phenolic resin; and / or Preferably, the inorganic component includes any one of barium sulfate, pyrite, chopped fibers, cryolite, and sapphire whiskers, or a mixture of two or more thereof; preferably, the chopped fibers are any one of glass fibers, basalt fibers, and aramid fibers, or a mixture of two or more thereof; Preferably, the composite adhesive comprises, by weight, 50-66 parts of modified phenolic resin, 10-15 parts of barium sulfate, 13-18 parts of pyrite, 8-13 parts of chopped fibers, 8-15 parts of cryolite, and 2-4 parts of sapphire whiskers.

5. The grinding wheel according to claim 4, characterized in that: The particle size of the modified phenolic resin is above 1000 mesh; preferably 1000-1200 mesh; And / or, the particle size of the barium sulfate, pyrite, and cryolite is above 325 mesh; preferably 325-400 mesh; And / or, the sapphire whisker is an α-aluminum oxide whisker, the whisker diameter is 0.1-1 μm, and the whisker length is 100-500 μm; preferably, the whisker diameter is 0.1-0.4 μm, and the whisker length is 100-300 μm; And / or, the chopped fibers have a single fiber diameter of 5 to 10 μm and a length of 1 to 4 mm.

6. The grinding wheel according to claims 1 to 5, characterized in that: The wetting agent is furfural; and / or The abrasive is a composition comprising α-Al2O3&ZrO2 eutectic corundum, coated brown corundum, and white corundum; preferably, The abrasive comprises 30-45 parts of α-Al2O3&ZrO2 eutectic corundum, 35-50 parts of coated brown corundum, and 10-15 parts of white corundum by weight; preferably 30-36 parts of α-Al2O3&ZrO2 eutectic corundum, 42-50 parts of coated brown corundum, and 12-15 parts of white corundum; and / or The particle size of the α-Al2O3&ZrO2 eutectic corundum is F14-F16, the particle size of the coated brown corundum is F20-F24, and the particle size of the white corundum is F24-F30.

7. The method for producing a grinding wheel according to any one of claims 1 to 6, characterized in that: The production method comprises the following steps: (1) Mixing: first mix the abrasive, adaptive friction modifier, and wetting agent, and then mix the mixed wet material with the composite adhesive; (2) Molding: The mixed material obtained in step (1) is placed in a molding mold for compression molding, and then subjected to curing treatment after demoulding.

8. The production method according to claim 7, characterized in that: The mixing in step (1) is carried out in a double-pot countercurrent mixer; And / or, in step (2), the mixed material obtained in step (1) is placed in a molding die for compression molding, comprising: controlling the molding die temperature to (120-150)°C±5°C for 4-6 minutes, then pressurizing to 8-15 MPa for 3-5 minutes and then releasing the pressure for 50-70 seconds; repeating the pressurization and pressure release operations 3-5 times; And / or, the curing treatment in step (2) includes a staged heating process, preferably a 3-5 stage heating process; preferably, any one or more of the heating rate, the insulation temperature and the cooling rate are accurately controlled during the curing process; more preferably, the heating rate is accurately controlled between 1 and 3°C / min, the cooling rate is between 1 and 3°C / min, and the insulation temperature fluctuation is ≤5°C during the curing process; further preferably, the specific process of the curing treatment includes: firstly keeping warm at (50-60)°C±5°C for 3-5h, then heating to 120-150°C at a heating rate of 1-3°C / min, then keeping warm at the temperature ±5°C for 6-8h, then heating to 185-195°C at a heating rate of 1-2°C / min, then keeping warm at the temperature ±2°C for 15-27h, and finally cooling to 15-35°C at a cooling rate of 1-3°C / min.

9. The production method according to claim 7 or 8, characterized in that: The production method further comprises performing anhydration treatment on the raw materials before mixing; preferably, the anhydration treatment on the raw materials is drying the raw materials to remove free water molecules; more preferably, the anhydration treatment on the raw materials comprises: keeping the organic components of the composite adhesive at a constant temperature of (50-60)°C±2°C for 10-20 hours, and / or, keeping the inorganic components of the composite adhesive at a constant temperature of (60-70)°C±2°C for 7-12 hours, and / or, keeping the abrasive at a constant temperature of 120-150°C for 20-30 hours, and / or, keeping the adaptive friction modifier at a constant temperature of 120-150°C for 20-30 hours; And / or, the step (1) further comprises sieving the material obtained by mixing the mixed wet material and the composite adhesive, preferably firstly passing the material through a F30-F40 mesh sieve, obtaining the material on the sieve, and then passing the material on a F8-F12 mesh sieve to recover the material under the sieve.

10. Use of the grinding wheel according to any one of claims 1 to 6 and / or the grinding wheel produced by the production method according to any one of claims 7 to 9 in rail grinding.

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