Use of silica

Obtained from the silica matting agent in many ways, according to its manufacturing process can be divided into two categories. One is the hydrothermal method of manufacture, production of silica morphology is relatively soft. Products made with silica gel texture is hard. After treatment, the two products can be made of standard silica matting agent. Process is the use of organic (wax) or an inorganic material to a certain degree of the silica surface modification. Compared with the silica matting agent, the treated silica with a different particle size, size distribution and pore volume. Hydrothermal method matting agent in particle size and distribution are also different. Unprocessed and processed products are different. Currently only one matting agent suitable for special occasions, the matting agent using pyrolysis manufacture, possess strong extinction efficiency, and particularly suitable for water-based coating systems.
Silica matting effect is relatively strong, higher concentrations may result in increased viscosity. A precipitate during storage of the trend, particularly in untreated silica. In order to avoid the accumulation, we can use paraffin or fumed silica. The matting agent can be adjusted 45 °, 60 ° and 85 ° azimuth extinction. Added silica matting agent can be cover coated with paint. All of these are 'stir-in' products.
Synthetic aluminum silicate can partially replace titanium dioxide used as a high-quality extender can be used in emulsion primer. The product was dried latex paint film can exhibit a balanced matting effect. In the long oil alkyd resin system can be used as a matting agent, but must be dispersed pigments and fillers. In addition to the powder coating systems, the silica matting agent can be applied to all of the coatings.

What is corundum

White fused alumina powder as raw materials in industry, at more than 2000 degrees by arc melting temperature after cooling is made by crushing plastic, magnetic separation to iron, sieving into a variety of particle size, its texture is dense, high hardness, grain formation of sharp corners form for use in manufacture of ceramics, resin bonded abrasives and grinding, polishing, sandblasting, precision casting (casting special corundum), etc., can be used to manufacture high-grade refractories, code-named "WA" on internationally accepted standards, national standards , the majority for export, there is a certain amount of supply domestic users.
Particle size in accordance with international standards and national standards of production, processing granularity according to user requirements. General size number of F4 ~ F320, depending on its chemical composition and different particle sizes. Prominent feature is the small crystal size, impact resistance, if the self-processing mill crushed particles are mostly spherical particles, dry surface cleaning, easy binding agent combination.
Corundum density:
Density is divided into two, one corundum bulk density, the second is the true density corundum.

Silica

Silica (quartzite) quartz as main mineral composition of the siliceous rocks. Manufacture of refractories refractory raw materials. 1820 by the British Young (wwYoun jealous digested first with lime made from silica sand silica, and then with British rock made of silicon silica.
Siliceous refractory silica sand can be used as raw materials for monolithic refractories.
According to the structure of dense silica is generally divided into two types of crystalline silica and silica cementation. Crystalline silica can be divided into veins of quartz and quartzite; cemented with silica quartz sandstone tunnel is divided into Shiyan and so on. By crystal transformation rate can be divided into fast, medium, slow, slow conversion of four special categories.
China Refractory materials zBD53ool at a price of silica quartz is a hexagonal Shao, also known as low-temperature quartz. Quartz is the high temperature quartz. Its crystal transition Fig. The melting point of cristobalite 1713 ℃, tridymite is 1 690 ℃.
Quartz heating process has a volume expansion of the conversion stage. Tridymite which best performance. In a more tridymite the existence of the products to form a strong skeleton. Tridymite easily soluble in the liquid phase, which makes the products, not because of the emergence of a liquid is deformed only when tridymite melted, to make products damage. So close to the softening temperature of the load of silica tridymite melting point. But to make quartz into tridymite mineralizing agent must be added to achieve. When the addition of iron scale (Feo + Fe: Oa) or flat slag can accelerate the transformation, heated to 140. ℃ above conversion intense and accompanied by a large volume expansion (when a mineralization agent), tridymite converted from the quartz, the volume expansion of 12% to 13%, without mineralizing agent, by the quartz British transforming the right volume when the prescription of 17% to 18 expansion write.
China silica rich in resources, mining more, Liaoning, Hebei, Shanxi, Shandong, Henan and other provinces. Silica generated during the grinding dust, easy to make people suffer from silicosis. Fused silica silica brick is mainly used for masonry carbonization chamber coke ovens and glass melting furnace, open-hearth furnace regenerators, etc., in the 1950s and before, are used for open-hearth furnace roof, brick after alkaline replaced.

Benefits and use of corundum

Corundum benefits: a high temperature, corrosion resistance, high strength and other properties, it poured with steel sliding gate, smelting rare metals, special alloys, ceramics, blast furnace lining (walls and tubes); chemical containers, spark plugs, anti- Thermal oxidation coating.
1, corundum is called dental industry: mainly used in the refractory, grinding wheels, sand blasting.
Sandblasting corundum - blasting abrasive hardness, high packing density, no free silica, heavy, good toughness, Okay corundum is the ideal "green" blasting material, widely used in aluminum, copper profiles of glass, washed jeans precision molds and other fields;
2, free grinding - grinding grade abrasives used in kinescope, optical glass, silicon, lenses, clocks, glass, crystal glass, jade and other areas of freedom ground, is commonly used advanced abrasive material;
3, resin abrasive - Abrasive have the right color, hardness, toughness, suitable particle section types and edge retention, resin abrasive used, the results are satisfactory;
4, Coated Abrasives - Abrasive sandpaper, gauze and other manufacturers of raw materials;
5, corundum functional filler - mainly used for automobile brake parts, specialty tires, specialty building products in areas such as construction of motorways, runways, terminals, parking lots, industrial flooring, sports and other wear-resistant materials ;
6. the filter media - is a new type of abrasive applications, the use of particulate abrasive medium as the bottom of the filter bed, to purify drinking water or waste water, is home to a new water filtration material, especially for non-ferrous metal processing, oil drilling mud weighting agent :
7, abrasive water-jet cutting - is abrasive cutting media, relying on high-pressure water jet cutting basic, used in oil (gas) pipelines, steel and other components of the cutting, is a new, environmentally friendly, safe cutting.
Customers: washing plant denim sandblasting workshop shipyard shipyard steel plant powder factory Shalun sandpaper, emery cloth factory floor crystal glass industry building industry, steel industry, metal industry, electronics industry, Qi car manufacturing docks, parking Hospital Stadium. Spray sands industry and other cooperation to meet various user needs in aggregate and abrasive floor.

The main function of corundum

(1) Due to high temperature, corrosion resistance, high strength and other properties, it poured with steel sliding gate, smelting rare metals, special alloys, ceramics, blast furnace lining (walls and tubes); chemical containers, spark plugs, thermal oxidation resistant coating.
(2) Because of hardness, wear resistance, high strength characteristics, in chemical systems, used a variety of responses utensils and pipes, chemical pump parts; doing mechanical parts, various molds, such as wire drawing dies, extrusion die nozzle pencil, etc.; make tools, dies abrasive, bulletproof material, human joints, sealing ring mold.
(3) corundum insulation materials, such as lightweight corundum bricks, corundum hollow spheres and fiber products, widely used in various high-temperature kiln furnace wall and roof, both high temperature insulation.
Size sand corundum corundum block by artificial selection, using the roll, milling, processing Barmac other equipment, particle size by the F8-F325. Mainly used for polishing, grinding, industrial grinding, etc., can also according to customer requirements for washing, pickling and other processing methods to meet the different needs of customers.

Green silicon carbide abrasives uses and characteristics

Green silicon carbide is quartz sand and coke for raw materials as a good thermal conductivity, high hardness of man-made materials. Green silicon carbide even at high temperatures with high strength, the elastic modulus when the temperature reaches 1600 ℃, only begins to decay. At a temperature of 2815 ° C begin to separate, but it does not melt at atmospheric pressure. Green silicon carbide suitable for use as super refractories, is also widely used for grinding areas.
Uses: 3-12 inch monocrystalline silicon, polycrystalline silicon, GaAs, quartz crystal wire cutting. Solar photovoltaic industry, the semiconductor industry, piezoelectric crystal engineering of industrial processing materials.
Features:
1, high-purity, large crystal silicon carbide material, the cutting of silicon carbide powder to ensure excellent cutting performance and stability of the physical condition.
2, plot size and shape of such a front edge, to ensure cutting edge material as silicon carbide powder balanced self-sharpening to ensure the material being cut TTV is minimized.
3, the particle size distribution is narrow and uniform.
4, a high thermal shock resistance and load softening temperature, which ensures that the cutting load of the small coefficient of linear expansion, thus ensuring the stability of the cutting; cutting machines and able to have a good adaptation of.
5, the surface is specially treated, powder with a large specific surface area and clean appearance, and polyethylene glycol coolant has good suitability.

The nature of quartz sand structure and classification

Quartz sand is a hard, wear-resistant, chemical stability of silicate minerals, the main mineral component is SiO2, quartz sand color is white or colorless, translucent, hardness 7, brittle no cleavage, conchoidal fracture, oil sheen, the relative density of 2.65, its chemical, thermal and mechanical properties have obvious anisotropy, acid-insoluble, slightly soluble in KOH solution, melting point 1750 ℃.
Quartz can be classified according to the quality of ordinary quartz sand, fine quartz sand, high purity quartz sand, fused silica sand.
1, ordinary quartz sand:
SiO2 ≥ 90-99% Fe2O2 ≤ 0.06-0.02%, refractoriness 1750 --- 1800 ℃, the appearance of some large particles, the surface of yellow cysts. Particle size range 5-220 mesh, users can request granularity production. Main purpose: metallurgy, ink silicon carbide, glass and glass products, ceramic, steel, water filtration, sodium silicate, chemical, jet noise and other industries.
2, refined quartz sand:
SiO2 ≥ 99-99.5% Fe2O3 ≤ 0.02-0.015%, selected high-quality ore complex processing. With 5-480 mesh size range, according to user requirements, the appearance of a white or crystalline. Main purpose: High quality glass, glass, refractories, smelting stone, precision casting, grinding wheel and other materials.
3, high purity quartz sand:
SiO2 ≥ 99.5-99.9% Fe2O2 ≤ 0.005%, is the use of 1-3 grade natural crystal stones and high quality natural stone, carefully selected, fine processing. Particle size range of 1-0.5mm, 0.5-0.1mm, 0.1-0.01mm, 0.01-0.005mm, according to user requirements.
4, fused quartz sand
Chemical composition: SiO2 99.9-99.99% Fe2O3 10PPM-25PPM maxLi2O 1-2PPM maxAl2O3 20-30PPM maxK2O 20-25PPM maxNa2O 10-20PPM max Physical Properties: colorless transparent block, granules or white powder. True specific gravity: 2.21; Mohs hardness: 7.0; PH value: 6.0.