Abrasive is the primary material for manufacturing grinding wheel, it bears a cutting work. Therefore, the abrasives must be sharp, and has high hardness, good heat resistance and toughness.
Particle size and its choice
 refers to the size of abrasive grain size. Abrasive and powder granularity is divided into two categories. For abrasive particle sizes larger than 40 μ m, known as the abrasive. Graded by the filter method, grain size, grain through a sieve to represent the number of perforations per inch length. Such as grain size 60# just passed with 60 holes per inch length of the screen. For the abrasive particle size less than 40 μ m, known as the powder. Classification of micro-measuring method, represented by w and the number after the grain size number, the w after the number that represents the actual size of the powder. W20 represent the actual size 20 μ m powder.