Method for manufacturing low-temperature grinding steel ball grinding wheel

Abstract

The application provides a low-temperature steel ball grinding wheel preparation method, which is composed of ceramic bond 45-50% and abrasive 50-55% in terms of mass percentage, wherein the ceramic bond is composed of clay 12-22%, feldspar 22-28% and boron glass 10-13%; the abrasive is composed of silicon carbide 20-40% and corundum 10-30%; manganese dioxide is added in the ceramic bond, and silicon carbide powder is added in the abrasive during the preparation process; the manganese dioxide is a fluxing agent, can effectively reduce the refractoriness during production, can improve the toughness of the grinding wheel, and can reduce the risk of cracking; the silicon carbide powder can improve the wear resistance of the grinding wheel, thereby prolonging the service life of the grinding wheel, and has excellent heat conduction performance, can ensure the stability of the grinding wheel during use, facilitates rapid heat conduction of the grinding heat, and reduces the thermal deformation of the workpiece.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of grinding wheel preparation equipment, in particular to a low-temperature grinding steel ball grinding wheel preparation method. BACKGROUND

[0002] The ceramic grinding steel ball grinding wheel is a special tool for grinding spherical steel balls for rolling bearings, and is mainly applied to the hard grinding process of steel ball processing. Steel balls are widely used in the bearing industry, and the surface roughness and surface precision requirements are very high. The surface precision of the smallest steel ball is 0.06 mm, and the technical index requirements are achieved through one-time grinding. Therefore, the quality requirements of the grinding wheel for grinding steel balls are particularly high. The quality and yield of the grinding steel ball grinding wheel directly affect the quality and yield of the steel ball, and indirectly affect the development of the bearing industry. Due to the characteristics of steel ball grinding and the requirements of grinding process, the grinding wheel for grinding steel balls must have high hardness, high density, fine granularity, uniform organization and certain toughness.

[0003] The ordinary grinding wheel is realized by high-temperature binder phase transition at 1100-1350℃, i.e. high-temperature reaction type binder phase transition, and low-melting filler to realize high shrinkage of the grinding wheel, to achieve high hardness of the product. However, at the low-temperature sintering temperature of 1050℃±30℃, the phase transition temperature cannot be reached, and at the firing temperature of 1200-1350℃, the energy consumption is high, which causes waste of resources and increases the production cost.

[0004] A ceramic binder grinding steel ball grinding wheel is disclosed in Chinese patent CN102363578B. The ceramic binder grinding steel ball grinding wheel is made of clay, feldspar, boron-containing glass, bentonite, and water manganite to form a high-strength high-shrinkage engineering ceramic binder. Then, the binder is combined with mixed material grinding material. The emulsion effect of boron glass is utilized to promote glass nucleation. The swelling bentonite and water manganite powder promote the formation of a high-strength high-shrinkage engineering ceramic structure. The binder is cold-pressed and high-pressure formed, and then fired at a certain temperature to obtain a ceramic binder grinding steel ball grinding wheel. The ceramic binder grinding steel ball grinding wheel needs to be fired at 1250℃, which requires high energy consumption, causing waste of resources and increasing production cost.

[0005] To solve the above problems, it is necessary to develop a low-temperature grinding steel ball grinding wheel preparation technology to reduce the manufacturing energy consumption of the ceramic grinding steel ball grinding wheel. SUMMARY

[0006] In view of the above situation, in order to overcome the defects of the prior art,

[0007] The present application provides a low-temperature grinding steel ball grinding wheel preparation method. The components are ceramic binder 45-50% and abrasive 50-55% by mass fraction, wherein,

[0008] The ceramic binder is composed of clay 12-22%, feldspar 22-28%, and boron glass 10-13%;

[0009] The abrasive is composed of silicon carbide 20-40% and corundum 10-30%;

[0010] The preparation method of the low-temperature grinding steel ball grinding wheel comprises the following steps:

[0011] (1) batching, mixing clay, feldspar, and boron glass to prepare a ceramic binder, and adding manganese dioxide during mixing to obtain a ceramic binder mixture;

[0012] mixing silicon carbide and corundum to prepare an abrasive, and adding silicon carbide powder during mixing to obtain an abrasive mixture;

[0013] mixing the ceramic binder mixture and the abrasive mixture to obtain a molding mixture;

[0014] (2) dry mixing and crushing, placing the molding mixture into a ball mill, and mixing and crushing for 2 hours at a speed of 50-60 rpm;

[0015] (3) wet mixing and stirring, adding a wetting agent at 80-90°C to the molding mixture after dry mixing and crushing, and mixing for 30 min;

[0016] (4) steaming, passing the wet-mixed molding material through an 8# sieve and placing it in a mold for 45 hours in a steaming chamber;

[0017] (5) drying, passing the steamed molding material through an 8-10# sieve, placing it in a mold, and placing it in a constant temperature environment at 40-45°C for 4 days;

[0018] (5) molding, placing the dried molding material in a size mold, and pressing it at a pressure of 8.4 MPa for 30 s to obtain a molded grinding wheel blank;

[0019] (6) sintering, placing the grinding wheel blank in a 1050°C furnace for 9-12 h, and then cooling it to room temperature to obtain a grinding wheel piece;

[0020] In step (1) batching, the mass of manganese dioxide added is 5% of the mass of the ceramic binder, and the mass of silicon carbide powder added is 5% of the mass of the abrasive.

[0021] Preferably, in step (3) wet mixing and stirring, the mass of the wetting agent added is 6-8% of the mass of the molding mixture.

[0022] Preferably, the particle size of the corundum is 120#.

[0023] Preferably, the particle size of the silicon carbide powder is 800-1000#.

[0024] Preferably, the corundum is one or a mixture of several corundums.

[0025] Preferably, the component of the wetting agent is water.

[0026] Compared with the prior art, the technical scheme provided by the application has the following remarkable effects:

[0027] The ordinary grinding wheel is realized high shrinkage and high hardness of the product by the phase transition of the ceramic binder at 1100-1350 DEG C, the phase transition of the high-temperature reaction type binder, and the filling of the low-melting substance. The low-temperature binder steel ball grinding wheel provided by the application adds 5% of manganese dioxide of the total mass of the ceramic binder and 5% of silicon carbide powder of the total mass of the abrasive when mixing, so as to improve the performance of the grinding wheel and reduce the sintering temperature. The manganese dioxide is a fluxing agent, which can effectively reduce the refractoriness during production, so that the grinding wheel produces sintering at 1050 DEG C ± 30 DEG C, and the toughness of the grinding wheel is improved, the risk of cracking is reduced, the sintering of the grinding wheel at 1050 DEG C ± 30 DEG C is solved, and the high shrinkage is maintained. The silicon carbide powder can improve the wear resistance of the grinding wheel, thereby prolonging the service life of the grinding wheel, and has excellent heat conduction performance, which can ensure the stability of the grinding wheel during use, rapidly discharge the grinding heat, and reduce the thermal deformation of the workpiece. DETAILED DESCRIPTION

[0028] The technical scheme of the application is further described in detail below in combination with the embodiments.

[0029] In the following embodiments, the particle size of the white corundum is 120#, the particle size of the silicon carbide powder is 900#, and water is used as the wetting agent.

[0030] Embodiment 1:

[0031] The low-temperature grinding steel ball grinding wheel comprises, by mass percentage, ceramic binder 45% and abrasive 50%.

[0032] The components of the ceramic binder are clay 18%, feldspar 22%, and boron glass powder 10%.

[0033] The components of the abrasive are white corundum 30% and silicon carbide 20%.

[0034] The low-temperature grinding steel ball grinding wheel preparation method comprises the following steps:

[0035] (1) dosing, mixing clay, feldspar, and boron glass to prepare a ceramic binder, adding manganese dioxide during mixing to obtain a ceramic binder mixture; mixing silicon carbide and corundum to prepare an abrasive, adding silicon carbide powder during mixing to obtain an abrasive mixture; and mixing the ceramic binder mixture and the abrasive mixture to obtain a molding mixture.

[0036] In this step, the mass of manganese dioxide added is 5% of the mass of the ceramic bond, and the mass of silicon carbide powder added is 5% of the mass of the abrasive.

[0037] (2) Dry crushing and mixing: the molding mixture after dry crushing and mixing is put into a ball mill and mixed at a speed of 60 rpm for 2 hours.

[0038] (3) Wet mixing and stirring: 90℃ water is added to the molding mixture after dry crushing and mixing, and mixed for 30 min.

[0039] In this step, the mass of water added is 7% of the mass of the molding mixture.

[0040] (4) Steaming: the molding mixture after wet mixing is passed through an 8# sieve and placed in a mold, and placed in a steaming room for 45 hours.

[0041] (5) Drying: the molding mixture after steaming is passed through a 10# sieve and placed in a mold, and placed at a constant temperature of 45℃ for 4 days.

[0042] (5) Molding: the molding mixture after drying is placed in a size mold and pressed at a pressure of 8.4 MPa for 30 S to obtain a molded grinding wheel blank.

[0043] (6) Sintering: the grinding wheel blank is placed in a furnace at 1050℃ and sintered for 10 h, and then cooled to room temperature to obtain a grinding wheel piece.

[0044] Example 2:

[0045] The low-temperature grinding steel ball grinding wheel has components of ceramic bond 45% and abrasive 50% by mass percentage.

[0046] The components of the ceramic bond are: clay 12%, feldspar 25%, and boron glass powder 13%.

[0047] The components of the abrasive are: white corundum 30% and silicon carbide 20%.

[0048] The preparation method of the low-temperature grinding steel ball grinding wheel is the same as that in Example 1.

[0049] The difference between Example 1 and Example 2 is that the components of the ceramic bond are different, and the remaining steps remain unchanged.

[0050] Example 3:

[0051] The low-temperature grinding steel ball grinding wheel has components of ceramic bond 45% and abrasive 50% by mass percentage.

[0052] The components of the ceramic bond are: clay 18%, feldspar 22%, and boron glass powder 10%.

[0053] The components of the abrasive are: white corundum 30%, silicon carbide 20%.

[0054] The low-temperature grinding steel ball grinding wheel preparation method comprises the following steps:

[0055] (1) batching, mixing clay, feldspar, borosilicate glass to prepare ceramic binder, adding manganese dioxide during mixing to obtain ceramic binder mixture; mixing silicon carbide and corundum to prepare abrasive; mixing the ceramic binder mixture and the abrasive to obtain a molding mixture.

[0056] In this step, the mass of manganese dioxide added is 5% of the mass of the ceramic binder.

[0057] (2) dry mixing and crushing, placing the molding mixture into a ball mill at a rotation speed of 60 rpm for 2 hours of dry mixing and crushing.

[0058] (3) wet mixing and stirring, adding water at 90°C to the molding mixture after dry mixing and crushing, and mixing for 30 min.

[0059] In this step, the mass of water added is 7% of the mass of the molding mixture.

[0060] (4) steaming, placing the wet-mixed molding material through an 8# sieve into a mold and placing it in a steaming chamber for 45 hours.

[0061] (5) drying, placing the steamed molding material through a 10# sieve into a mold and placing it at a constant temperature of 45°C for 4 days.

[0062] (5) molding, placing the dried molding material into a specification mold and pressing it at a pressure of 8.4 MPa for 30 S to obtain a molded grinding wheel blank.

[0063] (6) sintering, placing the grinding wheel blank in a furnace at 1050°C for 10 h, and then cooling it to room temperature to obtain a grinding wheel piece.

[0064] Example 3 differs from Example 1 in that only manganese dioxide is added during the preparation process, the addition of silicon carbide powder is cancelled, and the remaining steps remain unchanged.

[0065] Example 4:

[0066] The low-temperature grinding steel ball grinding wheel comprises, by mass percentage, 45% of ceramic binder and 50% of abrasive.

[0067] The components of the ceramic binder are: clay 18%, feldspar 22%, and borosilicate glass powder 10%.

[0068] The components of the abrasive are: white corundum 30%, silicon carbide 20%.

[0069] The low-temperature grinding steel ball grinding wheel preparation method comprises the following steps:

[0070] (1) batching, mixing clay, feldspar, borosilicate glass to prepare ceramic bond; mixing silicon carbide and corundum to prepare abrasive, adding silicon carbide powder during mixing to obtain abrasive mixture; mixing the ceramic bond and the abrasive mixture to obtain molding mixture.

[0071] In this step, the mass of manganese dioxide added is 5% of the mass of the ceramic bond, and the mass of silicon carbide powder added is 5% of the mass of the abrasive.

[0072] (2) dry mixing, placing the molding mixture into a ball mill and mixing at a speed of 60 rpm for 2 hours to dry and crush.

[0073] (3) wet mixing and stirring, adding water at 90°C to the molding mixture after dry mixing and crushing, and mixing for 30 min.

[0074] In this step, the mass of water added is 7% of the mass of the molding mixture.

[0075] (4) steaming, placing the wet-mixed molding material through an 8# sieve into a mold and placing it in a steaming chamber for 45 hours.

[0076] (5) drying, placing the steamed molding material through a 10# sieve into a mold and placing it at a constant temperature of 45°C for 4 days.

[0077] (5) molding, placing the dried molding material into a size mold and pressing it at a pressure of 8.4 MPa for 30 s to obtain a molded grinding wheel blank.

[0078] (6) sintering, placing the grinding wheel blank in a furnace at 1050°C for 10 h, and then cooling it to room temperature to obtain a grinding wheel piece.

[0079] Example 4 differs from Example 1 in that only silicon carbide powder is added, without adding manganese dioxide, and the remaining steps remain unchanged.

[0080] Comparative Example 1:

[0081] The low-temperature grinding steel ball grinding wheel is made of raw materials in the following mass percentages:

[0082] Ceramic bond: clay 18%, feldspar 22%, borosilicate glass powder 10%;

[0083] Abrasive: white corundum 30%, silicon carbide 20%;

[0084] The preparation method of the low-temperature grinding steel ball grinding wheel comprises the following steps:

[0085] (1) batching, mixing clay, feldspar, borosilicate glass to prepare ceramic bond; mixing silicon carbide and corundum to prepare abrasive; mixing the ceramic bond and the abrasive to obtain molding mixture.

[0086] In this step, the mass of manganese dioxide added is 5% of the mass of the ceramic bond, and the mass of silicon carbide powder added is 5% of the mass of the abrasive.

[0087] (2) Dry crushing and mixing: the molding mixture after dry crushing and mixing is put into a ball mill and mixed at a speed of 60 rpm for 2 hours.

[0088] (3) Wet mixing and stirring: water at 90°C is added to the molding mixture after dry crushing and mixing, and mixed for 30 min.

[0089] In this step, the mass of water added is 7% of the mass of the molding mixture.

[0090] (4) Steaming: the molding mixture after wet mixing is passed through an 8# sieve and placed in a mold, and placed in a steaming room for 45 hours.

[0091] (5) Drying: the molding mixture after steaming is passed through a 10# sieve and placed in a mold, and placed at a constant temperature of 45°C for 4 days.

[0092] (5) Molding: the molding mixture after drying is placed in a mold with a pressure of 8.4 MPa for 30 seconds to obtain a molded grinding wheel blank.

[0093] (6) Sintering: the grinding wheel blank is placed in a furnace at 1050°C and sintered for 10 hours, and then cooled to room temperature to obtain a grinding wheel piece.

[0094] The difference between Comparative Example 1 and Example 1 is that no silicon carbide powder and manganese dioxide is added, and the remaining steps remain unchanged.

[0095] The following compares and analyzes Example 1, Example 2, Example 3, Example 4, and Comparative Example 1:

[0096] Under the same parameters, the sintering conditions at 1050°C, hardness, shrinkage, and sintering temperature of the molded low-temperature grinding steel ball grinding wheel are compared.

[0097] Table 1 Performance comparison of low-temperature grinding steel ball grinding wheel

[0098]

[0099] Since Comparative Example 1 did not sinter at 1050°C, it was observed that the temperature was increased to 1260°C to sinter; Examples 1, 2, and 3 all sintered at 1050°C; and Example 4 had poor shrinkage at 1050°C.

[0100] From the data in Table 1, it can be seen that Examples 1 and 2 added the same manganese dioxide and silicon carbide powder, and sintered at 1050°C, with high shrinkage.

[0101] Example 3 only added manganese dioxide, canceled the addition of silicon carbide powder, resulting in sintering at 1050℃, but the shrinkage was poor.

[0102] Example 4 only added silicon carbide powder, without adding manganese dioxide, resulting in poor sintering and shrinkage.

[0103] Comparative Example 1 did not add silicon carbide powder and manganese dioxide, resulting in no sintering at 1050℃, sintering did not occur until 1260℃, and the shrinkage was 9.1%.

[0104] Therefore, by adding manganese dioxide to the ceramic bond and adding silicon carbide powder to the abrasive, the sintering temperature of the low-temperature abrasive steel ball grinding wheel can be reduced to 1050℃, while also showing good hardness and shrinkage, effectively reducing energy consumption.

Claims

1. A method for preparing a low-temperature grinding steel ball grinding wheel, characterized in that, By mass percentage, the composition is 45-50% ceramic binder and 50-55% abrasive. The ceramic binder consists of 12-22% clay, 22-28% feldspar, and 10-13% borosilicate glass. The abrasive is composed of 20-40% silicon carbide and 10-30% corundum; The method for preparing a low-temperature grinding ball grinding wheel includes the following steps: (1) Ingredients: Clay, feldspar and borosilicate glass are mixed to prepare ceramic binder. Manganese dioxide is added during mixing to obtain ceramic binder mixture. Abrasives are prepared by mixing silicon carbide and corundum, with silicon carbide micro powder added during the mixing process to obtain the abrasive mixture. The ceramic binder mixture and the abrasive mixture are mixed to obtain a molding mixture; (2) Pulverize and dry mix: Put the molded mixture into a ball mill and mix at a speed of 50-60 rpm for 2 hours to pulverize and dry; (3) Wet mixing: Add a wetting agent at 80℃-90℃ to the shaped mixture after crushing and dry mixing, and mix for 30 minutes; (4) Curing: After the wet-mixed molding material is passed through an 8# sieve, it is placed in the mold and placed in the curing room for 45 hours; (5) After drying and curing, the molded material is passed through an 8-10# sieve, placed in a mold, and kept at a constant temperature of 40-45℃ for 4 days; (5) Molding: Place the dried molding material into a standard mold and press it with a pressure of 8.4 MPa for 30 seconds to obtain the molded grinding wheel blank; (6) Sintering: Place the grinding wheel blank in a furnace at 1050℃±30℃ and sinter for 9-12 hours, then cool to room temperature to obtain the grinding wheel part; In step (1), the mass of manganese dioxide added is 5% of the mass of ceramic binder, and the mass of silicon carbide micro powder added is 5% of the mass of abrasive.

2. The method for preparing a low-temperature grinding ball grinding wheel according to claim 1, characterized in that, In step (3) wet mixing, the mass of the added wetting agent is 6-8% of the mass of the molding mixture.

3. The method for preparing a low-temperature grinding ball grinding wheel according to claim 1, characterized in that, The corundum has a particle size of 120#.

4. The method for preparing a low-temperature grinding ball grinding wheel according to claim 1, characterized in that, The particle size of the silicon carbide micro powder is 800-1000#.

5. The method for preparing a low-temperature grinding ball grinding wheel according to claim 1, characterized in that, The corundum is a mixture of one or more types of corundum.

6. The method for preparing a low-temperature grinding ball grinding wheel according to claim 2, characterized in that, The wetting agent is composed of water.

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