Magnesia grinding tool and production process thereof

Abstract

A magnesite grinding tool of the present invention is mainly prepared from the following components: 15-20 parts by weight of magnesium oxide, 16-19 parts by weight of magnesium chloride aqueous solution, 1.2-2.5 parts by weight of filler, 3-5 parts by weight of polishing material, 2.8-5.2 parts by weight of abrasive, and 1.8-3.2 parts by weight of pore-forming agent; wherein the filler is preferably stearic acid, other fillers are also acceptable, the polishing material is α-alumina, and the abrasive is silicon carbide or white corundum. The pore-forming agent is doped inside or on the surface of the produced magnesite grinding tool by adopting this formula, so that the pore-forming agent doped in the magnesite grinding tool will dissolve when it encounters water during grinding, so that the surface of the magnesite grinding tool is formed with fine holes, and the holes on the surface of the magnesite grinding tool are used to significantly improve the sharpness of the magnesite grinding tool, thereby overcoming the problem that the existing magnesite grinding tool has limited sharpness and cannot be used for precision grinding. The present invention also discloses a production process of magnesite grinding tool.

Description

Technical Field

[0001] The present invention relates to the field of abrasive tool processing, and in particular to a magnesia abrasive tool and a production process thereof. Background Art

[0002] Abrasives for grinding natural stones such as granite and marble are classified by the bond: metal bond abrasives, resin bond abrasives, ceramic bond abrasives, rubber bond abrasives, etc. Among them, ceramic bond abrasives have the advantages of high strength, good heat resistance, sharp cutting, high grinding efficiency, etc., and are widely used in stone abrasives. Among ceramic bond abrasives, magnesia abrasives are a special type of ceramic abrasives. Their main features are abundant raw materials, low price, room temperature hardening, no need for complex equipment such as ovens and high-temperature furnaces, simple manufacturing process, good lubrication of the bond, low friction coefficient, which can reduce friction heat and improve the roughness of the processed surface; magnesia abrasives have better grinding effects than other abrasives in the processing of certain materials, and are particularly suitable for grinding cutting tools such as razor blades, scissors, and paper cutters, high carbon steel, stainless steel and other materials with high hardness, high toughness, and high grinding heat, stone, glass, ceramics and other non-metallic materials, and can also be used for shelling rice and sorghum.

[0003] Although magnesite abrasives are cost-effective, have a simple manufacturing process, and do not require complex production equipment, in the past, magnesite abrasives were not sharp enough for fine grinding and the grinding effect was not good.

[0004] In view of this, the inventor conducted in-depth research on the above-mentioned issues, which resulted in the present case. Summary of the invention

[0005] In view of this, an object of the present invention is to provide a magnesite grinding tool capable of improving the sharpness of the magnesite grinding tool.

[0006] Another object of the present invention is to provide a production process for magnesite abrasive tools which can improve the sharpness of the magnesite abrasive tools.

[0007] In order to achieve the above object, the solution of the present invention is: a magnesia abrasive tool, mainly prepared from the following components: 15-20 parts by weight of magnesium oxide, 16-19 parts by weight of magnesium chloride aqueous solution, 1.2-2.5 parts by weight of filler, 3-5 parts by weight of polishing material, 2.8-5.2 parts by weight of abrasive, and 1.8-3.2 parts by weight of pore former;

[0008] The pore former is mainly prepared from the following components: A) 60-75% by mass of water-soluble crystals, B) 9-18% by mass of alcohol-soluble linear resins, C) 5-10% by mass of powder fillers, and D) 9-18% by mass of anhydrous ethanol.

[0009] The component A is one of sodium chloride, urea, magnesium sulfate heptahydrate or potassium tetraoxalate.

[0010] The component B is one of alkyd resin and phenolic resin.

[0011] The component C is one of α-alumina and calcium carbonate.

[0012] The filler is stearic acid, the polishing material is α-alumina, and the abrasive is silicon carbide or white corundum.

[0013] A production process of magnesia grinding tools is prepared by the following steps:

[0014] Step 1: Prepare the materials, weigh all the components of the magnesite grinding tool described in any one of claims 1 to 5,

[0015] Step 2: Stirring, pouring the magnesium chloride aqueous solution and magnesium oxide powder in step 1 into a stirring tank and stirring for 4-6 minutes, then pouring the polishing material and abrasive in step 1 into the stirring tank and stirring for 2-4 minutes, then pouring the pore-forming agent into the stirring tank and stirring for 3-5 minutes to obtain a mixed slurry;

[0016] Step 3: Molding. Pour the mixed slurry from step 2 into the mold cavity of the molding mold. After standing for 1.8-2.2 hours, immediately transfer it to the drying room for molding and curing. When the temperature of the mixed slurry in the molding mold reaches 78-85℃, push it out of the drying room and demold it from the molding mold to obtain the magnesia abrasive.

[0017] The pore-forming agent is prepared by the following steps:

[0018] Step 1), weighing all components of the pore-forming agent of claim 1, and then crushing the weighed component B to obtain a powdered component B;

[0019] Step 2), stirring for the first time, mixing component D weighed in step 1 with powdered component B in step 1 and stirring until powdered component B is completely dissolved to obtain a resin solution, wherein the mass ratio of component D to powdered component B is 1:1;

[0020] Step 3), stirring for the second time, pouring the component A weighed in step 1 and the resin solution prepared in step 2 into a horizontal mixer and stirring, so that the resin solution is evenly coated on the surface of each water-soluble crystal, to obtain a number of semi-finished products;

[0021] Step 4), stirring for the third time, adding the component C weighed in step 1 into the horizontal mixer of step 3 and stirring together with all the semi-finished products of step 3, so that a powder filler layer is evenly attached to the surface of each semi-finished product, and a plurality of granules are obtained;

[0022] Step 5), sieving, pouring all the particles in the horizontal mixer in step 4 into a sieve for filtration to obtain evenly dispersed crystals;

[0023] Step 6), drying, spreading all the crystals obtained in step 5 on a soft breathable cloth for air drying to obtain a pore-forming agent.

[0024] In the above steps 3) and 4), the stirring time is 3-5 minutes.

[0025] The mesh number of the above-mentioned sieve is 4 meshes.

[0026] In the above step 6), the soft breathable fabric is a non-woven fabric, and a fan is used for air drying.

[0027] After adopting the above technical scheme, a magnesia grinding tool of the present invention adds a self-developed pore-forming agent to the molding raw material of the original magnesia grinding tool, so that the interior or surface of the molded magnesia grinding tool is doped with a granular pore-forming agent, and the self-developed pore-forming agent will dissolve when it comes into contact with water. In this way, when the magnesia grinding tool is being polished, the polishing water will be washed on the magnesia grinding tool. At this time, the pore-forming agent doped in the magnesia grinding tool will dissolve when it comes into contact with water, so that tiny holes are formed on the surface of the magnesia grinding tool. The holes on the surface of the magnesia grinding tool can significantly improve the sharpness of the magnesia grinding tool, thereby overcoming the problem that the existing magnesia grinding tool has limited sharpness and cannot be used for precision polishing. DETAILED DESCRIPTION

[0028] In order to further explain the technical solution of the present invention, the present invention is described in detail below through specific embodiments.

[0029] The magnesite abrasive tool of the present invention is mainly prepared from the following components: 15-20 parts by weight of magnesium oxide, 16-19 parts by weight of magnesium chloride aqueous solution, 1.2-2.5 parts by weight of filler, 3-5 parts by weight of polishing material, 2.8-5.2 parts by weight of abrasive, and 1.8-3.2 parts by weight of pore-forming agent; wherein the filler is preferably stearic acid, and other fillers are also acceptable, the polishing material is α-aluminum oxide, and the abrasive is silicon carbide or white corundum.

[0030] The pore former is mainly prepared from the following components: A) 60-75% by mass of water-soluble crystals, B) 9-18% by mass of alcohol-soluble linear resins, C) 5-10% by mass of powder fillers, and D) 9-18% by mass of anhydrous ethanol.

[0031] Among them, component A is one of sodium chloride, urea, magnesium sulfate heptahydrate or potassium tetraoxalate, preferably urea or potassium tetraoxalate, component B is one of alkyd resin and phenolic resin, preferably alkyd resin, which is rosin-modified alkyd resin, and component C is one of α-alumina and calcium carbonate.

[0032] The production process of a magnesite grinding tool of the present invention is prepared by the following steps:

[0033] Step 1: Prepare materials, weigh magnesium oxide, magnesium chloride aqueous solution, filler, polishing material, abrasive and pore-forming agent; wherein the filler is preferably stearic acid, other fillers may also be used, such as magnesium sulfate, the polishing material is α-alumina, and the abrasive is silicon carbide or white corundum. In addition, the preparation method of magnesium chloride aqueous solution (also called brine) is to brine magnesium chloride and water at a temperature of 30-32°C to obtain a magnesium chloride aqueous solution with a Baume degree of 30-34; the use of this concentration of magnesium chloride aqueous solution makes the strength of the abrasive tool sufficient and does not produce cracks, avoiding the problem that the concentration of magnesium chloride in the traditional brine is too high, causing the abrasive body to shrink and crack, or the concentration of magnesium chloride is too low, causing the abrasive tool to be insufficiently hardened and causing insufficient strength;

[0034] Step 2: Stirring, pour the magnesium chloride aqueous solution and magnesium oxide powder in step 1 into a stirring tank and stir for 4-6 minutes, preferably 5 minutes, then pour the polishing material and abrasive in step 1 into the stirring tank, stir for 2-4 minutes, preferably 3 minutes, after stirring, pour the pore-forming agent into the stirring tank, stir for 3-5 minutes, preferably 5 minutes, to obtain a mixed slurry;

[0035] Step 3: Molding. Pour the mixed slurry from step 2 into the mold cavity of a molding mold for molding magnesia mold. After standing for 1.8-2.2 hours, immediately transfer it to a drying room for molding and curing. Preferably, it is immediately transferred to a drying room after standing for 2 hours. At this time, the temperature of the drying room is 40 degrees. When the temperature of the mixed slurry in the molding mold reaches 78-85°C, push it out of the drying room and demold it from the molding mold. The optimal demolding temperature of the mixed slurry is 82°C, and you can get a magnesia mold.

[0036] In the present invention, the pore-forming agent is prepared by the following steps:

[0037] Step 1: Prepare the materials, weigh component A, component B, component C and component D, component B is a block structure, and then crush the weighed component B to obtain a powdered component B;

[0038] Step 2: First stirring, put the component D weighed in step 1 and the powdered component B in step 1 into a plastic bucket and mix and stir until the powdered component B is completely dissolved to obtain a resin solution, wherein the mass ratio of the component D to the powdered component B is 1:1;

[0039] Step 3: Stirring for the second time, pouring component A weighed in step 1 and the resin solution prepared in step 2 into a horizontal mixer and stirring for 3-5 minutes, so that the resin solution is evenly wrapped on the outer surface of each water-soluble crystal, and obtaining a plurality of semi-finished products, that is, each semi-finished product is composed of an inner and outer layer, the inner layer is the water-soluble crystal, and the outer layer is the resin solution wrapped on the outer surface of the water-soluble crystal;

[0040] Step 4: Stir for the third time, add the component C weighed in step 1 into the horizontal mixer in step 3 and stir together with all the semi-finished products in step 3, the stirring time is 3-5 minutes, so that a powder filler layer is evenly attached to the surface of each semi-finished product, and a plurality of granules are obtained, each of which is composed of an inner and outer layer, the inner layer is the semi-finished product, and the outer layer is the powder filler;

[0041] Step 5: Screening: pour all the particles in the horizontal mixer in step 4 into a sieve with a mesh size of 4 to obtain evenly dispersed crystals;

[0042] Step 6: Drying. All the crystals obtained in step 5 are spread on a soft breathable cloth for air drying to obtain a pore-forming agent. When spreading, a layer of soft breathable cloth is spread on the ground or on a wooden board. This soft breathable cloth is a non-woven fabric. That is, when screening, workers place the screen above the non-woven fabric for direct screening, so that the screened crystals fall directly onto the non-woven fabric at even intervals and are spread out, and then blow-dried with a fan to make the crystals quickly air-dried, without ethanol on the surface, to obtain dry particles, which are the pore-forming agent of the present invention.

[0043] After adopting the above technical scheme, a magnesia grinding tool of the present invention has a pore-forming agent in the raw material of the magnesia grinding tool, and the pore-forming agent is immediately transferred to the drying room for thermal curing about 2 hours after being poured into the molding mold, so that the pore-forming agent will not dissolve during the molding process. In this way, the interior or surface of the molded magnesia grinding tool is doped with granular pore-forming agent. When used, the magnesia grinding tool needs to be polished and flushed with water. When the polishing water is flushed on the surface of the magnesia grinding tool, the pore-forming agent doped on the surface of the magnesia grinding tool will dissolve when it meets water, so that fine holes are formed on the surface of the magnesia grinding tool, that is, the surface of the magnesia grinding tool is not a smooth surface, but is covered with a plurality of fine holes. The holes on the surface of the magnesia grinding tool are used to significantly improve the sharpness of the magnesia grinding tool, thereby overcoming the problem that the existing magnesia grinding tool has limited sharpness and cannot be used for precision grinding. In addition, a production process of a magnesia grinding tool of the present invention has the advantages that the produced grinding tool has improved sharpness and the entire production operation is simple.

[0044] The above embodiments do not limit the structure and steps of the present invention. Any appropriate changes or modifications made by ordinary technicians in the relevant technical field should be deemed to be within the patent scope of the present invention.

Claims

1. A magnesia grinding tool, It is characterized in that Prepared by the following steps: Step 1: preparing materials. The magnesia abrasive tool is mainly prepared from the following components: 15-20 parts by weight of magnesium oxide, 16-19 parts by weight of magnesium chloride aqueous solution, 1.2-2.5 parts by weight of filler, 3-5 parts by weight of polishing material, 2.8-5.2 parts by weight of abrasive, and 1.8-3.2 parts by weight of pore-forming agent; The pore former is mainly prepared from the following components: A) 60-75% by mass of water-soluble crystals, B) 9-18% by mass of alcohol-soluble linear resins, C) 5-10% by mass of powder fillers, and D) 9-18% by mass of anhydrous ethanol; Step 2: Stirring, pouring the magnesium chloride aqueous solution and magnesium oxide powder in step 1 into a stirring tank and stirring for 4-6 minutes, then pouring the polishing material and abrasive in step 1 into the stirring tank and stirring for 2-4 minutes, then pouring the pore-forming agent into the stirring tank and stirring for 3-5 minutes to obtain a mixed slurry; Step 3: Forming: pour the mixed slurry from step 2 into the mold cavity of the forming mold, let it stand for 1.8-2.2 hours, and then immediately transfer it to the drying room for forming and curing. When the temperature of the mixed slurry in the forming mold reaches 78-85°C, push it out of the drying room and demold it from the forming mold to obtain the magnesia abrasive. The preparation method of the pore-forming agent is achieved by the following steps: Step 1), weighing all the components of the pore-forming agent, and then crushing the weighed component B to obtain a powdered component B; Step 2), stirring for the first time, mixing the component D weighed in step 1) with the powdered component B in step 1) and stirring until the powdered component B is completely dissolved to obtain a resin solution, wherein the mass ratio of the component D to the powdered component B is 1:1; Step 3), stirring for the second time, pouring the component A weighed in step 1) and the resin solution prepared in step 2) into a horizontal mixer and stirring, so that the resin solution is evenly coated on the surface of each water-soluble crystal, to obtain a number of semi-finished products; Step 4), stirring for the third time, adding the component C weighed in step 1) into the horizontal mixer in step 3) and stirring together with all the semi-finished products in step 3), so that a powder filler layer is evenly attached to the surface of each semi-finished product, and a plurality of granules are obtained; Step 5), sieving, pouring all the particles in the horizontal mixer in step 4) into the sieve for filtration to obtain evenly dispersed crystals; Step 6), drying, spreading all the crystals obtained in step 5) on a soft breathable cloth for air drying to obtain a pore-forming agent.

2. A magnesite grinding tool according to claim 1, Features: The component A is one of sodium chloride, urea, magnesium sulfate heptahydrate or potassium tetraoxalate.

3. The magnesite grinding tool according to claim 1, Features: The component B is one of alkyd resin and phenolic resin.

4. The magnesite grinding tool according to claim 1, Features: The component C is one of α-alumina and calcium carbonate.

5. The magnesite grinding tool according to claim 1, Features: The filler is stearic acid, the polishing material is α-alumina, and the abrasive is silicon carbide or white corundum.

6. The magnesite grinding tool according to claim 1, Features: In the above steps 3) and 4), the stirring time is 3-5 minutes.

7. The magnesite grinding tool according to claim 1, Features: The mesh number of the above-mentioned sieve is 4 meshes.

8. The magnesite grinding tool according to claim 1, Features: In the above step 6), the soft breathable fabric is a non-woven fabric, and is air-dried using a fan.