One of the important properties of an abrasive is its hardness, which must be harder than the material to be processed. Mohs hardness tester is commonly used to measure the hardness of various abrasives. Another important property of abrasives is toughness or bulk strength. This property can be controlled by changing the mix, purity, particle size and crystal structure of the raw materials to suit various applications.
For the manufacture of abrasive products, except for powdered talc and iron oxide, all raw materials need to be crushed and screened. The screening particle size should be 4 to 900, that is, the diameter is about 6 mm (mm) to 6 microns. (One thousandth of a millimeter) or finer. The grinding wheel is the most important abrasive product. It is made of abrasives and binders mixed in a certain proportion, molded and then sintered. Finally, it must be shaped, balanced and over-speed tested. Abrasive cloth and sandpaper are another type of abrasive products with large production volume. They are made of abrasive grains bonded to the base material (cloth or paper) and cut into products of different specifications after drying. Others are powdery or granular abrasives. After screening, they need to undergo certain processes, such as abrasives for grinding or polishing. Mineral ointment or wax and other auxiliary materials are usually added to adapt to the needs of different working conditions.