A pressed ceramic super fine oil stone and a method of making the same

Abstract

This invention proposes a pressed ceramic super oilstone and its preparation method. By mass percentage, it consists of 90%-95% abrasive and 5%-10% ceramic binder, wherein: the abrasive is composed of corundum with a particle size of F800-F1500; the ceramic binder is composed of 5%-16% clay, 12%-60% borosilicate glass, 10%-30% bentonite, 15%-40% dextrin powder, and 8%-54% potassium silicate. This invention relates to a method for preparing pressed ceramic super-refined oilstone. It utilizes dextrin solution and water glass to create a corresponding wetting agent, increasing overall cohesion. The mixing of potassium silicate and dextrin solution allows the colloidal properties of dextrin to improve the rheology and stability of the potassium silicate solution, thereby increasing its adhesive properties and heat resistance. This enhances the bonding and prevents cracking during drying. Furthermore, it reduces the drying time from 10-15 days to 2-3 days, a reduction of over 80%, significantly improving oilstone production efficiency and lowering the scrap rate.

Description

Technical Field

[0001] This invention relates to the field of oilstone production technology, and in particular to a pressed ceramic super-refined oilstone and its preparation method. Background Technology

[0002] Oilstones are grinding tools widely used in precision machining, metal surface treatment, and arts and crafts, renowned for their fine texture and excellent wear resistance. With the rapid development of high-end equipment, the requirements for oilstones, especially ceramic ultra-precision oilstones, are becoming increasingly stringent. Ceramic ultra-precision oilstones mostly use ceramic binders, which possess characteristics such as high strength, good heat resistance, minimal heat generation and clogging during grinding, easy control of machining accuracy, and ease of dressing. They are widely used in the ultra-precision machining of components for high-end precision equipment such as aerospace engines, instruments, and high-precision machine tools. In the ultra-precision machining process of precision equipment components, only when the surface roughness meets the specified standards can high-precision components with excellent performance be manufactured. Oilstones play a crucial role in the final quality of high-end components and can significantly affect the efficiency of the grinding process.

[0003] During the production of ceramic superfine oilstones, the evaporation of moisture in the wetting agent reduces the contact area between the abrasive and the ceramic binder, sometimes causing detachment. This leads to cracks and fissures on the surface of the superfine oilstone during subsequent drying and firing, rendering the material unusable. To reduce these issues, the superfine oilstone is typically placed in a constant temperature and humidity environment for 10-15 days to allow for slow evaporation of moisture. However, this method is time-consuming, inefficient, and results in a low product qualification rate, severely impacting production efficiency. While a mixture of coarse-grained ceramic binder and ultrafine abrasive can shorten the production cycle, improve efficiency, and achieve a high product qualification rate, the coarse binder particles can easily damage the workpiece during grinding, resulting in poor surface roughness and failing to meet the requirements for ceramic superfine oilstones.

[0004] There is an urgent need to develop a method for pressing ceramic super oilstone and its preparation to solve the problems of long production cycle and low product qualification rate of ceramic super oilstone mentioned above. Summary of the Invention

[0005] In view of the above situation, in order to overcome the shortcomings of the existing technology;

[0006] This invention provides a pressed ceramic superabrasive stone and its preparation method, comprising, by mass percentage, 90%-95% abrasive and 5%-10% ceramic binder, wherein:

[0007] The abrasive is composed of corundum with a particle size of F800-F1500;

[0008] The ceramic binder consists of 5%-16% clay, 12%-60% borosilicate glass, 10%-30% bentonite, 15%-40% dextrin powder, and 8%-54% potassium silicate.

[0009] Preferably, the potassium silicate in the ceramic binder can be replaced with an equal mass of sodium silicate, and the corundum is either white corundum or brown corundum.

[0010] A method for preparing an oilstone, comprising the following steps:

[0011] S1. Preparation of ceramic binder: Add the above ceramic binder raw materials into an ultrasonic vibrator and mix them evenly. The ultrasonic vibration time is 0.5-2 hours. After mixing, the finished ceramic binder is obtained.

[0012] S2. Mixing of oilstones: Add the abrasive and finished ceramic binder into the three-dimensional mixing pot at the same time and stir evenly for 2-4 hours at a speed of 60 r / min. Then pour the evenly mixed material into the mixing pot and add dextrin solution and water glass in sequence. Continue stirring for 20-30 minutes to obtain the molding material of oilstones.

[0013] S3. Pressing of the oilstone: Pass the mixed molding material through a 20#-46# sieve. Pour the molding material through the sieve into the molding mold. Use a scraper and fork to stir the molding material evenly and level it. Place the mold containing the molding material under a hydraulic press for pressing. Press continuously at a pressure of 10-15Mpa 4 times. The holding time for each pressing is 15-30s. After demolding, the oilstone blank can be obtained.

[0014] S4. Forming of oilstone: Dry the oilstone blank at room temperature for 2-4 days, then put it into a high-temperature furnace and fire it at 950℃-1070℃ for 10-26 hours with a heating rate of 1-3℃ / min. After firing, keep it at the temperature for 3-5 hours and allow it to cool naturally to obtain the finished oilstone.

[0015] Preferably, in step S2, the mass of the dextrin solution is 1%-1.5% of the total weight of corundum and ceramic binder, and the concentration is 30%-40%wt.

[0016] Preferably, the water glass in step S2 is 1.6%-1.9% of the total weight of corundum and ceramic binder, and has a concentration of 35%-45%wt. The water glass can be replaced with an equivalent mass of glycerol or an aqueous solution of PEG2000.

[0017] Compared with the prior art, the present invention provides a pressed ceramic super-fine oilstone and its preparation method, which has the following beneficial effects:

[0018] This invention removes the conventionally used feldspar and talc powder from the ceramic binder formulation and selects a wetting agent that can react with dextrin solution and water glass. The wetting agent is potassium silicate or sodium silicate, which can increase the overall connectivity. The mixing of potassium silicate with dextrin solution improves the rheology and stability of the potassium silicate solution due to the colloidal properties of dextrin, thereby increasing its adhesive properties and heat resistance, thus enhancing the bonding state and preventing cracking. Furthermore, the combination of potassium silicate and water glass provides a good alkaline environment and strong complexing effect for the water glass, increasing connectivity and preventing cracking during drying. At the same time, it can shorten the drying period from 10-15 days to the current 2-3 days, reducing the time by more than 80%, greatly improving the production efficiency of oilstone and reducing the scrap rate of oilstone. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1:

[0021] This oilstone, by weight percentage, consists of 92% abrasive and 8% ceramic binder, wherein:

[0022] The abrasive is composed of white corundum with a particle size of F1000;

[0023] The ceramic binder consists of 7.5% clay, 21.25% borosilicate glass, 15% bentonite, 25% dextrin powder, and 31.25% potassium silicate.

[0024] The mass of the dextrin solution was 1.2% of the total weight of the corundum and ceramic binder, and the concentration was 35% wt.

[0025] The water glass has a mass of 1.7% of the total weight of corundum and ceramic binder, and a concentration of 40% wt.

[0026] A method for preparing an oilstone includes the following steps:

[0027] S1. Preparation of ceramic binder: The above-mentioned ceramic binder raw materials are added into an ultrasonic vibrator and mixed evenly for 1 hour. The finished ceramic binder is obtained after mixing.

[0028] S2. Mixing of oilstones: Add the abrasive and finished ceramic binder into the three-dimensional mixing pot at the same time and stir evenly for 2.5 hours at a speed of 60 r / min. Then pour the evenly mixed material into the mixing pot and add dextrin solution and water glass in sequence. Continue stirring for 25 minutes to obtain the molding material of oilstones.

[0029] S3. Pressing of the oilstone: Pass the mixed molding material through a 30# sieve. Pour the molding material through the sieve into the molding mold. Use a scraper and fork to stir the molding material evenly and level it. Place the mold containing the molding material under a hydraulic press for pressing. Press continuously at a pressure of 11 MPa 4 times. The holding time for each pressing is 20 seconds. After demolding, the oilstone blank can be obtained.

[0030] S4. Forming of oilstone: Dry the oilstone blank at room temperature for 2 days, then put it into a high-temperature furnace and fire it at 980℃ for 14 hours with a heating rate of 1.5℃ / min. After firing, keep it at the temperature for 4 hours and allow it to cool naturally to obtain the finished oilstone.

[0031] Example 2:

[0032] This oilstone, by weight percentage, consists of 95% abrasive and 5% ceramic binder, wherein:

[0033] The abrasive is composed of white corundum with a particle size of F800;

[0034] The ceramic binder consists of 10% clay, 15% borosilicate glass, 5% bentonite, 20% dextrin powder, and 50% potassium silicate.

[0035] The mass of the dextrin solution is 1% of the total weight of corundum and ceramic binder, and the concentration is 35% wt.

[0036] The water glass is 3% of the total weight of corundum and ceramic binder, and has a concentration of 40% wt.

[0037] The production steps are the same as in Example 1;

[0038] The difference between Example 2 and Example 1 is that the percentages of abrasive and ceramic binder and the proportion of raw materials are changed, the particle size of the abrasive is adjusted, and the quality of dextrin solution and water glass is changed. The remaining steps are the same as in Example 1.

[0039] Example 3:

[0040] This oilstone, by weight percentage, consists of 94% abrasive and 6% ceramic binder, wherein:

[0041] The abrasive is composed of white corundum with a particle size of F1200;

[0042] The ceramic binder consists of 7.5% clay, 21.25% borosilicate glass, 15% bentonite, 25% dextrin powder, and 31.25% sodium silicate.

[0043] The mass of the dextrin solution was 1.1% of the total weight of corundum and ceramic binder, and the concentration was 35% wt.

[0044] The water glass has a mass of 3.0% of the total weight of corundum and ceramic binder, and a concentration of 40% wt.

[0045] The production steps are the same as in Example 1;

[0046] The difference between Example 3 and Example 1 is that the percentage of abrasive and ceramic binder is changed, the particle size of the abrasive is changed, and the mass of dextrin solution and water glass added is adjusted. The remaining steps are the same as in Example 1.

[0047] Comparative Example 1:

[0048] This oilstone, by weight percentage, consists of 92% abrasive and 8% binder, wherein:

[0049] The abrasive is composed of white corundum with a particle size of F1000;

[0050] The binder consists of 7.5% clay, 21.25% borosilicate glass, 15% bentonite, 25% dextrin powder, 26.25% feldspar, and 5% talc.

[0051] The mass of the dextrin solution was 1.2% of the total weight of corundum and binder, and the concentration was 35% wt.

[0052] The water glass has a mass of 1.7% of the total weight of corundum and binder, and a concentration of 40% wt.

[0053] A method for preparing an oilstone includes the following steps:

[0054] S1. Preparation of binder: Add the above binder raw materials into an ultrasonic vibrator and mix them evenly. The ultrasonic vibration time is 1 hour. After mixing, the finished binder is obtained.

[0055] S2. Mixing of oilstone: Add the abrasive and finished product binder into the three-dimensional mixing pot at the same time and stir evenly for 2.5 hours at a speed of 60 r / min. Then pour the evenly mixed material into the mixing pot and add dextrin liquid and water glass in sequence. Continue stirring for 25 minutes to obtain the molding material of oilstone.

[0056] S3. Pressing of the oilstone: Pass the mixed molding material through a 30# sieve. Pour the molding material through the sieve into the molding mold. Use a scraper and fork to stir the molding material evenly and level it. Place the mold containing the molding material under a hydraulic press for pressing. Press continuously at a pressure of 11 MPa 4 times. The holding time for each pressing is 20 seconds. After demolding, the oilstone blank can be obtained.

[0057] S4. Forming of oilstone: Dry the oilstone blank at room temperature for 10 days, then put it into a high-temperature furnace and fire it at 980℃ for 20 hours with a heating rate of 1.1℃ / min. After firing, keep it at the temperature for 4 hours and allow it to cool naturally to obtain the finished oilstone.

[0058] The difference between Comparative Example 1 and Example 1 is that the potassium silicate in the binder was replaced with the same mass of feldspar and talc powder, and the parameters in the molding step were adjusted accordingly based on the drying of the oilstone. The remaining steps were the same as in Example 1.

[0059] Comparative Example 2:

[0060] This oilstone, by weight percentage, consists of 92% abrasive and 8% binder, wherein:

[0061] The abrasive is composed of white corundum with a particle size of F800;

[0062] The binder consists of 7.5% clay, 21.25% borosilicate glass, 15% bentonite, 25% dextrin powder, 26.25% feldspar, and 5% talc.

[0063] The mass of the dextrin solution was 1.2% of the total weight of corundum and binder, and the concentration was 35% wt.

[0064] The water glass has a mass of 1.7% of the total weight of corundum and binder, and a concentration of 40% wt.

[0065] The production steps are the same as those in Comparative Example 1;

[0066] The difference between Comparative Example 2 and Example 1 is that the particle size of the abrasive is changed, and the potassium silicate in the binder is replaced with the same mass of feldspar and talc powder. The production steps are the same as those in Comparative Example 1.

[0067] Comparative Example 3:

[0068] This oilstone, by weight percentage, consists of 94% abrasive and 6% binder, wherein:

[0069] The abrasive is composed of white corundum with a particle size of F1200;

[0070] The binder consists of 7.5% clay, 21.25% borosilicate glass, 15% bentonite, 25% dextrin powder, 26.25% feldspar, and 5% talc.

[0071] The mass of the dextrin solution was 1.2% of the total weight of corundum and binder, and the concentration was 35% wt.

[0072] The water glass has a mass of 1.7% of the total weight of corundum and binder, and a concentration of 40% wt.

[0073] The production steps are the same as those in Comparative Example 1;

[0074] The difference between Comparative Example 3 and Example 3 is that the potassium silicate in the binder was replaced with the same mass of feldspar and talc powder, and the mass of dextrin solution and water glass added was adjusted. The production steps were the same as those in Comparative Example 1.

[0075] The following is a comparative analysis of Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2, and Comparative Example 3:

[0076] Under the same parameters, the number of firings, drying time, amount of waste products after drying, number of firings, firing time, amount of waste products after firing, and pass rate of Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2, and Comparative Example 3 were compared respectively.

[0077] Table 1 Performance Comparison

[0078]

[0079]

[0080] As can be seen from the table above, the data of Examples 1, 2, and 3, which use the preparation method in combination with the ceramic binder, are all better than those of Comparative Examples 1, 2, and 3, which use ordinary binders. Among them, Example 1 has the best overall pass rate. The amount of waste after drying and firing in Example 1 is less than that in Examples 2 and 3. At the same time, the table also shows that the drying time of Examples 1, 2, and 3 is shorter than that of Comparative Examples 1, 2, and 3, indicating that the preparation method can effectively shorten the drying time of the oilstone and also shorten the firing time accordingly.

[0081] Therefore, it can be seen that by combining potassium silicate or sodium silicate with dextrin solution, the oilstone prepared by this method can effectively shorten the firing time, and the qualified rate of oilstone produced by this method is better than that of other oilstones. It also effectively shortens the drying cycle and reduces the amount of waste after drying. In addition, the oilstone does not crack during drying, which greatly improves production efficiency.

Claims

1. A pressed ceramic super-refined oil stone characterized in that, By weight percentage, it consists of 90%-95% abrasive and 5%-10% ceramic binder, wherein: The abrasive is composed of corundum with a particle size of F800-F1500; The ceramic binder consists of 5%-16% clay, 12%-60% borosilicate glass, 10%-30% bentonite, 15%-40% dextrin powder, and 8%-54% potassium silicate. The pressed ceramic super-oilstone is prepared by a method including the following production steps: S1. Preparation of ceramic binder: Add the above ceramic binder raw materials into an ultrasonic vibrator and mix them evenly. The ultrasonic vibration time is 0.5-2 hours. After mixing, the finished ceramic binder is obtained. S2. Mixing of oilstones: Add the abrasive and finished ceramic binder into the three-dimensional mixing pot at the same time and stir evenly for 2-4 hours at a speed of 60 r / min. Then pour the evenly mixed material into the mixing pot and add dextrin solution and water glass in sequence. Continue stirring for 20-30 minutes to obtain the molding material of oilstones. S3. Pressing of the oilstone: Pass the mixed molding material through a 20#-46# sieve. Pour the molding material through the sieve into the molding mold. Use a scraper and fork to stir the molding material evenly and level it. Place the mold containing the molding material under a hydraulic press for pressing. Press continuously at a pressure of 10-15Mpa 4 times. The holding time for each pressing is 15-30s. After demolding, the oilstone blank can be obtained. S4. Forming of oilstone: Dry the oilstone blank at room temperature for 2-4 days, then put it into a high-temperature furnace and fire it at 950℃-1070℃ for 10-26 hours. The heating rate is 1-3℃ / min. After firing, keep it at the temperature for 3-5 hours. After natural cooling, the finished oilstone is obtained. The water glass in step S2 has a mass of 1.6%-1.9% of the total weight of corundum and ceramic binder, and a concentration of 35%-45%wt. In step S2, the mass of the dextrin solution is 1%-1.5% of the total weight of corundum and ceramic binder, and the concentration is 30%-40%wt.

2. The pressed ceramic super-fine oilstone according to claim 1, characterized in that, The corundum is either white corundum or brown corundum.

3. A method for preparing an oilstone, used to produce a pressed ceramic super-refined oilstone as described in claims 1 to 2, characterized in that, The method for preparing the oilstone includes the following steps: S1. Preparation of ceramic binder: Add the above ceramic binder raw materials into an ultrasonic vibrator and mix them evenly. The ultrasonic vibration time is 0.5-2 hours. After mixing, the finished ceramic binder is obtained. S2. Mixing of oilstones: Add the abrasive and finished ceramic binder into the three-dimensional mixing pot at the same time and stir evenly for 2-4 hours at a speed of 60 r / min. Then pour the evenly mixed material into the mixing pot and add dextrin solution and water glass in sequence. Continue stirring for 20-30 minutes to obtain the molding material of oilstones. S3. Pressing of the oilstone: Pass the mixed molding material through a 20#-46# sieve. Pour the molding material through the sieve into the molding mold. Use a scraper and fork to stir the molding material evenly and level it. Place the mold containing the molding material under a hydraulic press for pressing. Press continuously at a pressure of 10-15Mpa 4 times. The holding time for each pressing is 15-30s. After demolding, the oilstone blank can be obtained. S4. Forming of oilstone: Dry the oilstone blank at room temperature for 2-4 days, then put it into a high-temperature furnace and fire it at 950℃-1070℃ for 10-26 hours with a heating rate of 1-3℃ / min. After firing, keep it at the temperature for 3-5 hours and allow it to cool naturally to obtain the finished oilstone.

4. The method for preparing an oilstone according to claim 3, characterized in that, In step S2, the mass of the dextrin solution is 1%-1.5% of the total weight of corundum and ceramic binder, and the concentration is 30%-40%wt.

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