Abrasives are composed of abrasives, binders, fillers, pores and appendages.

Basic requirements for abrasives:

1. The hardness is higher than the hardness of the processed material;

2. It has a certain degree of toughness, strength and sharpness.

3. It should have a certain degree of mechanical strength.

4. Maintain inherent hardness and strength at high temperature (ie red hardness or thermal stability).

Classification of abrasives:

Abrasives can be divided into two categories: natural and man-made according to their sources. According to their properties, they can be divided into two categories: ordinary abrasives and super-hard abrasives.

Commonly used natural abrasives:

1. Natural diamond: Diamond abrasive tools have a series of advantages such as high efficiency, long life, low cost, and good grinding quality.

2. Quartz sand: also known as silica sand, sand composed of more than 95% quartz particles.

3. Garnet sand: Use loose sand abrasive for soft marble block sawing.

4. Natural corundum: The main composition is A1203. The Mohs hardness is 9, second only to diamond.

Commonly used artificial abrasives:

1. Brown corundum: suitable for grinding materials with higher tensile strength, and the price is relatively cheap.

2. White corundum: The grinding ability is slightly higher than that of brown corundum (0.12 of diamond). Appropriate finishing.

3. Chrome corundum: purple or rose color, slightly higher grinding ability than white corundum (0.13 of diamond), especially suitable for forming grinding. It is widely used for precision grinding of alloy gears, cutting tools, thread management tools and instrument parts.

4. Silicon carbide: commonly known as emery, its wear resistance is 0.25-0.28 of diamond, brittle and sharp, and it is a kind of abrasive with a wide range of uses.

5. Synthetic diamond: The wear resistance is almost the same as that of natural diamond, and it will gradually replace the tradition in the stone industry.