Importante Propiedades de abrasivos y cómo hacer ellos

The important properties of abrasives and how to manufacture them are essential materials for every kind of precision product. Many natural abrasives have been replaced by artificial abrasives. In addition to diamond, the performance of natural abrasives is not stable, but it still has its use value. One of the important properties of abrasive is its hardness, it must be harder than the material to be processed, commonly used Mohs hardness tester to determine the hardness of various abrasives. Another important performance of abrasives is toughness or volume strength. This property can be controlled by changing the mixing amount, purity, particle size and crystal structure of the raw material to be suitable for various applications. In the manufacture of abrasive products, all raw materials, except powdered talc and iron oxide, need to be crushed and screened.A sharp, hard material for grinding softer material surfaces. There are two main types of abrasives: natural abrasives and artificial abrasives. According to the hardness of the classification of superhard abrasives and ordinary abrasives two categories. There is a wide range of abrasives, from softer household detergents and gem abrasives to the hardest material diamond.Abrasives are an essential material in the manufacture of every precision product. Many natural abrasives have been replaced by artificial abrasives. In addition to diamond, the performance of natural abrasives is not stable, but it still has its use value. Diamond is the hardest abrasive, producing mainly in South Africa, accounting for 95% of the world's total production, the rest is Brazil, Australia, Guyana and Venezuela and other places. Industrial diamond from gray white to black range, after grinding can be made grinding wheel, abrasive belt, polishing wheel and grinding powder.The chemical composition of natural corundum is alumina, the main origin is South Africa, and it is used to polish and grind glass. Emery is also a natural form of alumina, generally speaking, it is not as pure as corundum, the main origin of Greece, Turkey, used to make emery cloth or sandpaper. Garnet is used to manufacture coated abrasives, which are mostly used in the wood and leather industries. Flint is often used to make sandpaper. Quartz was one of the earliest materials used for grinding wheels, and is still used to make knives and to work glass. Pumice stone comes from volcanoes and is used to make polishing powder. Diatomaceous earth is the ingredient for polishing powder and oil stone. Other natural abrasives are talc, silica, feldspar, black silica and chalk.Since the 1970s, a large number of artificial abrasives have been produced, of which the main ones are silicon carbide and alumina. Silicon carbide commonly known as carborundum, pure silica sand and coke mixed with a small amount of wood chips, into the electric furnace, roasted at 2,200~2,480 degree for about 36 hours and produced. Alumina commonly known as corundum, industrial commonly used electric arc furnace heating to melt bauxite made of, white transparent as a heat-sensitive metal abrasive, black for processing castings and steel. Artificial diamond grinding wheel is the highest hardness of abrasives, necessary for the grinding of carbide cutting tools. Artificial diamond can also be made into various shapes and sizes of tools to be suitable for cutting glass and ceramics. Boron carbide is harder than silicon carbide and is not suitable for making grinding wheels. It can be used in place of expensive diamonds when polishing hard materials. Cubic boron carbide is twice as hard as silicon carbide and 2.5 times as hard as alumina, making it effective in grinding some tool steels.One of the important properties of abrasive is its hardness, it must be harder than the material to be processed, commonly used Mohs hardness tester to determine the hardness of various abrasives. Another important performance of abrasives is toughness or volume strength. This property can be controlled by changing the mixing amount, purity, particle size and crystal structure of the raw material to be suitable for various applications.For the manufacture of abrasive products, all raw materials, except powdered talc and iron oxide, need to be crushed and screened, and the screening size should be 4 to 900, that is, the diameter of about 6 mm (mm) to 6 microns (one-thousandth of 1 mm) or finer. Grinding wheel is the main abrasive products, by a certain proportion of abrasive and binder mixed, sintered after die forming, after must also be shaped, balance and overspeed test. Emery cloth and sandpaper are another kind of abrasive products with large output, which are bonded by abrasive particles on the base material (cloth or paper) and cut into products of different specifications after drying. Other powder or granular abrasive, after screening, need to undergo a certain process, such as grinding or polishing abrasives, usually with mineral ointment or wax and other auxiliary materials, to meet the needs of different working conditions.Abrasives are widely used in industry, especially when processing high-precision or low-roughness parts or particularly hard parts, abrasives and abrasives are essential. In addition, for the sharpening of knives and the cutting of hard materials, the grinding wheel is also an essential tool. In the automobile manufacturing industry, the piston ring and the cylinder, the valve and the seat of the close match, transmission and gear accuracy, etc., must be processed with abrasives and abrasives to ensure. Other related new products, such as the plastic bonding roller mill with the medium, for a large number of parts deburring save time, improve productivity.The production technology of abrasives has advanced significantly. The efficiency of diamond grinding wheels is four times higher than that of 14 years ago; The total cost of zirconia-alumina grinding wheels used in rolling mills is only 25% of what it was in 1948, and the speed is seven times higher. The current problem is that the basic theory of grinding action is not clear and needs to be studied; The specifications of the products are complex, the varieties are wide, and it is not easy to simplify.