47results about How to "Small median diameter" patented technology

The invention discloses a preparation method of a 3D printing inorganic powder molding material. The method is characterized in that the method comprises the following steps: 1, powder material pretreatment: mixing 10-30% of acetone with 62-85% of a powdery material and 2-10% of gamma-(2,3-epoxypropoxy)propyltrimethoxysilicane, and grinding the obtained mixture at a rotating speed of 500-1000rpm for 1-2h to obtain a pretreated powdery material; and 2, molding material preparation: adding 40-65% by mass of acetone, adding 2-8% of polyvinyl formal, stirring for dissolving, adding 30-55% of the pretreated powdery material, stirring for uniform mixing, putting the obtained solution in a grinder, carrying out normal temperature mixing grinding at a rotating speed of 500-1000rpm for 6-9h, and carrying out spray drying to obtain the 3D printing inorganic powder molding material. The 3D printing inorganic powder molding material can be directly molded at a temperature of 190-210DEG C under a pressure of 1-10MPa without sprinkling a binder, and has the advantages of simple preparation technology, easy condition control, low production cost and easy industrialized production.

The invention discloses a high-precision rare-earth polishing powder and a method for preparing the same. The high-precision rare-earth polishing powder is characterized in that D50 particle diameter is between 0.5 and 1.80 mu m; the powder also meets the conditions that D10 is more than or equal to 0.5D50, D90 is less than or equal to 2D50, and D100 is less than or equal to 3D50; a cerium lanthanum nitrate or cerium lanthanum chloride solution is added to an ammonium oxalate solution with PH value of between 4.5 and 5.5 to generate monodisperse lanthanum cerium oxalate or lanthanum cerium praseodymium oxalate deposit; and the deposit is used as a crystal seed to prepare the high-precision rare-earth polishing powder. The high-precision rare-earth polishing powder prepared by the method does not need airflow pulverization and precise classification and has the characteristics of small median particle diameter and narrow granularity distribution range; the stability of the wearing resistance and polishing precision is easy to control; and the quality of a product has small fluctuation.

The invention discloses a preparation method of jade polishing powder. The method is characterized by comprising the steps of feeding 12-26% of cerium chloride and 20-32% of zirconium oxychloride into a reactor according to the mass percent concentration, and dissolving the mixture in water; then, feeding 15-30% of aluminium oxide, 8-15% of silicon nitride, 2-6% of chromic oxide and 0.5-3% of dispersing agent into the water solution, and stirring to obtain slurry; dissolving 15-30% of ammonium oxalate into water, and then feeding the product into the slurry, wherein the sum of the content of all the components except water of the slurry is 100%; stirring under the normal pressure, heating up to 85 DEG C, and carrying out a reaction for 30-36h; then, heating up to 120 DEG C, and carrying out the reaction for 2-4h; carrying out calcination for 2-4h at the temperature of 950-1000 DEG C, cooling and crushing by airflow to obtain the jade polishing powder. The preparation technology is simple, easy in control of conditions, low in production cost and easy in industrial production. When being used for the polishing process, the polishing powder is good in powder polishing effect, high in glossiness, free from scratch, high in flatness and less in power dosage.

The invention discloses an aluminum oxide polishing powder and a production method thereof. The aluminum oxide polishing powder is characterized in that a D50 particle size is smaller than 2.0 microns and satisfies that D10 is no less than 0.5 times of D50, D90 is no more than 2 times of D50 and D100 is no less than 3 times of D50. The preparation method comprises the following steps of pulping raw materials of alpha-aluminum oxide with water, carrying out classification and obtaining a product. The aluminum oxide polishing powder has the advantages of small median particle diameter, narrow granularity distribution range, easy control of the polishing accuracy stability and small fluctuation of the product quality, can be used for accurate polishing processing of electronic product components including glasses for liquid crystal display screens, flat plane displays, optical elements, ultrathin glass substrates and glass magnetic discs and can also be used for preparing aluminum oxide polishing solution for polishing chemical machinery.

The invention discloses a preparation method for a nano-silicon nitride powder for the laser sintering 3D printing technology. The preparation method is characterized by comprising the following steps: firstly, using gamma-glycidoxypropyl trimethoxysilane for the pretreatment of nano-silicon nitride powder in an ethanol solvent to obtain pretreated nano-silicon nitride powder; then, adding the following components by mass percentage into a grinding machine to obtain a mixture I: 84%-90% of pretreated nano-silicon nitride powder, 3%-8% of epoxy resin and 0.4%-1.0% of pyromellitic dianhydride, starting the grinding machine, grinding the mixture I at a revolution speed of 300 rpm for 5 min, and then adding 5%-10% of acetone to obtain a mixture II, turning on the grinding machine, grinding the mixture II at a revolution speed of 300 rpm for 30-40 min, and drying the grinded mixture II to obtain the nano-silicon nitride powder for laser sintering 3D printing technology. The nano-silicon nitride powder for the laser sintering 3D printing technology can be molded directly under laser sintering, is simple in preparation process, low in production cost, and easy to realize industrial production, and the condition is easy to control.

The invention discloses a preparation method of rare earth-doped silicon carbide composite polishing powder. The method is characterized by comprising the steps of feeding 45-70% of cerous nitrate according to the mass percent concentration, and dissolving into water, then respectively feeding 8-20% of aluminium oxide, 5-15% of silicon carbide and 0.5-1% of dispersing agent, and stirring to obtain slurry; then feeding 14-25% of oxalic acid into the slurry, stirring and dissolving, wherein the sum of the content of all the components except water of the slurry is 100%; stirring under the normal pressure, heating up to 80-90 DEG C, and carrying out a reaction for 2-6h at the temperature of 800-1000 DEG C; cooling and crushing by airflow to obtain the rare earth-doped silicon carbide composite polishing powder. The preparation technology is simple, easy in control of conditions, low in production cost and easy in industrial production. When being used for stone polishing process, the polishing powder is good in powder polishing effect, high in glossiness, less scratch, high in flatness and less in power dosage.

The invention discloses a preparation method of granite polishing powder. The method is characterized in that the method comprises the following steps: dissolving 3-12% by mass of ammonium dichromate and 6-18% of zirconium oxychloride in water, adding 50-70% of alumina, adding 2-10% of titanium dioxide, adding 0.5-1% of a surfactant, stirring to form a slurry, adding 10-20% of ammonium carbonate, stirring for dissolving, stirring under normal pressure, heating to 70-75DEG C, reacting for 20-30h, evaporate to dryness, heating to 190-195DEG C, reacting for 2-4h, roasting at 1000-1100DEG C for 1-2h, cooling, and carrying out air flow crushing to obtain the granite polishing powder. The preparation method has the advantages of simplicity, easy condition control, low production cost, and easy industrialized production. The granite polishing powder is used for the granite polishing process, and has the advantages of good polishing effect, glossiness, small scratch quantity, high flatness, and small amount.

The invention discloses a preparation method of silicon nitride ceramic powder through laser sintering and rapid moulding. The method comprises the following steps: pretreating silicon nitride ceramic powder by using polyvinyl alcohol to obtain the pretreated silicon nitride ceramic powder; then in a grinder, adding the following components by mass percentage: 80-85% of pretreated silicon nitride ceramic powder, 4-8% of phenolic resin, 2-5% of polyvinyl butyral and 0.8-3% of triethylenetetramine, turning on the grinder with rotating speed being 250 rotation/min, grinding for 5 minutes, adding 7-12% of acetone, wherein sum of the components is 100%, and rotating speed of the grinder is 250 rotation/min, grinding for 40-60 minutes, and drying to obtain the silicon nitride ceramic powder. The material can be directly moulded under laser sintering, moulding precision is high, and the method has the advantages of simple preparation technology, easy control of condition, low production cost, and easy industrial production.

The invention discloses a preparation method of a 3D printing zirconium dioxide powder moulding material. The preparation method of the 3D printing zirconium dioxide powder moulding material is characterized by comprising the following steps: carrying out pre-treatment on zirconium dioxide powder in an ethanol solvent by adopting allyl trimethoxy silicane, so that pretreated zirconium dioxide powder is obtained; then adding 60-72% by mass of petroleum ether and 3-8% by mass of polyethylene into a reactor, heating, stirring, dissolving, and then adding 20-30% by mass of pretreated zirconium dioxide powder and 1-4% by mass of azodiisobutyronitrile, wherein the sum of the percents by mass of all the components is one hundred percent; heating while stirring until the temperature is increased to 80+/-5 DEG C, carrying out constant temperature refluxing reaction for 6-8 hours, cooling to room temperature, and then carrying out spray drying, so that the 3D printing zirconium dioxide powder moulding material is obtained. The 3D printing zirconium dioxide powder moulding material can be directly moulded without spraying a binding agent in a range that the temperature is increased to 125-137 DEG C by heating and has the advantages that a preparation technology is simple, conditions are easy to control, production cost is low, and industrial production can be easily realized.

The invention discloses a preparation method of marble polishing powder. The method is characterized by comprising the following process steps of adding the following ingredients in percentage concentration by mass into a grinding machine: 47 to 53 percent of oxalate dihydrate, 12 to 15 percent of aluminum oxide and 5 to 10 percent of stannic oxide; performing grinding and uniform mixing; adding 6 to 10 percent of sodium binoxalate and 15 to 21 percent of stearic acid; performing grinding and uniform mixing; then adding 2 to 4 percent of paraffin powder and 0.3 to 1.0 percent of fatty alcohol polyoxy ether, wherein the sum of all ingredients is hundred percent; performing grinding and uniform mixing; obtaining the marble polishing powder with the particle diameter being 2.0 to 10 mu m. The polishing powder has the advantages that chemical reaction is taken between the polishing powder and marble in the polishing process; the chemical polishing characteristics are realized, so that the polishing effect of the polishing powder is good; the luster degree is high; scratch marks are few; the flatness and smoothness degree is high; the consumption is low; the corrosion of oxalic acid can be buffered through the addition of the sodium binoxalate.

The invention discloses a preparation method of a boron nitride composite polishing solution. The preparation method is characterized in that by mass, 28-38% of water, 18-26% of ammonium dichromate, 12-20% of zirconium oxychloride and 24-32% of nano boron nitride are added to a grinding machine, the grinding machine is started, and a BN-Cr2O3-ZrO2 compound is prepared through grinding, drying and calcining; by mass, 70-78% of water, 2.0-4.0% of lignosulfonate, 3.0-5.0% of isopropyl alcohol, 1.0-5.0% of potassium bromate and 14-22% of BN-Cr2O3-ZrO2 compound are added to a reactor, a stirring reaction is conducted for 4-6 h at the rotating speed of 300 r/min, and the boron nitride composite polishing solution is obtained. The preparation process is simple, conditions are easy to control, the production cost is low, and industrial production is easy. In the polishing process, the advantages of being good in liquid polishing effect, free of scratches, high in flatness, small in dosage, resistant to abrasion and easy to wash are achieved.