Among the commonly used abrasives, emery is mentioned more often, it isBrown corundum, white corundum, black corundum, silicon carbideand other abrasives collectively, because of the hardness, good toughness, strong grinding ability and other advantages, is widely used in polishing, grinding, sandblasting, casting, etc., the following with the small series, detailed understanding of the characteristics and uses of various emery abrasives.
Brown corundum Brown corundum is the bauxite, coke (anthracite), iron filings into the electric arc furnace, by high temperature melting and smelting reduction to obtain tan artificial corundum, also known as emery, refractory up to 1900 °C, melting point can reach 2250 °C, the main component is alumina (Al2O3), and contains a small amount of Fe, Si, Ti, etc.
The properties of brown corundum are mainly determined by the content of alumina (Al2O3). The higher the content, the higher its hardness and the stronger the grinding force. It can be used in refractory materials, coated abrasives, sandblasted abrasives, wear-resistant floors, consolidation abrasives, functional fillers, filter media, waterjet cutting and other fields.
White corundum White corundum is a kind of emery artificial abrasives, which uses industrial alumina powder as raw material, which is made by high temperature melting in an arc and cooling, crushed and shaped, magnetically separated to remove iron, and screened into a variety of particle sizes.
The main component of white corundum is aluminum oxide, which also contains a small amount of iron oxide, silicon oxide and other components, which is white. Outstanding features are small crystal size, impact resistance, dense texture, high hardness, particle formation of sharp corners, suitable for the manufacture of ceramics, resin consolidation abrasives and grinding, polishing, sandblasting, casting and other fields, can also be used to manufacture refractory materials.
Black corundum Black corundum and brown corundum are more common emery abrasives in life, which use bauxite as the main raw material, add a small amount of reducing agent, and then smelt it at high temperature in an electric arc furnace. Its color is black, characterized by moderate hardness, toughness, sharp edges and corners and wear-resistant, strong self-sharpening, grinding heat, high cleanliness of polished workpieces, can be used for polishing aluminum products and stainless steel, manufacturing sandpaper, emery cloth and resin abrasives and other fields.
silicon carbide The silicon carbide in emery has two kinds of black silicon carbide and green silicon carbide, which is made of quartz sand, petroleum coke (or coal coke), wood chips as raw materials through resistance furnace high temperature smelting, it has the advantages of high hardness, good grinding performance, etc., as an abrasive, can be used as an abrasive, such as grinding wheels, oil stones, grinding heads, sand tiles, etc.
It can also be used in semiconductors, lightning rods, circuit components, high temperature applications, ultraviolet detectors, structural materials, astronomy, disc brakes, clutches, diesel particulate filters, filament pyrometers, ceramic films, cutting tools, heating elements, nuclear fuel, jewelry, steel, protective gear and other fields.
