The purpose of abrasive grain size is to control the product parameters to obtain the desired surface effect. The size of the abrasive particles directly affects the cutting performance, workpiece surface quality and energy consumption. When selecting abrasivegrains, the workpiece material, hardness, surface finish requirements, processing environment, and type of abrasive machine must be taken into account.
The following table (Table 1) provides a guide for the basic abrasive grain size range of various abrasives.
Table 1. Abrasive Grain Size Range Comparison Chart
Abrasive Basic Grain Size Range
Aluminum Oxide 16 to 220 mesh
Cubic Boron Nitride 60 to 600 mesh
Diamond 45 to 1200 mesh
Silicon Carbide 16 to 220 mesh
Aluminum Oxide is an extremely hard, non-metallic mineral abrasive. It is relatively inexpensive and can be found in the widest range of abrasive sizes of all synthetic abrasive materials. Aluminum Oxide is the most popular abrasive because it provides fast cutting, economical performance and is cool cutting. This abrasive is best used for grinding steel, high alloy steel or heat-treated steels, which are too hard for other abrasives.
Cubic Boron Nitride (CBN) is a second-generation synthetic abrasive material that is harder than aluminum oxide and features high temperature and chemical resistance. CBN is best suited for grinding hardened steels and ferrous metals. CBN abrasive is available in fine and ultra-fine ranges (60 to 600 mesh)
Diamond is the hardest abrasive on the market and it is suitable for grinding extremely hard materials such as glass, ceramics and ferrous carburizing steels. Its ultra-fine grain size ranges between 45 to 1200 mesh and its cutting performance is considerably greater than that of aluminum oxide.
Silicon Carbide is a hard and blocky abrasive material with poor self-sharpening properties. It’s suitable for grinding metals such as aluminum, brass, bronze and cast iron. Silicon carbide is sharper and harder than aluminum oxide and its grains range from 16 to 220 mesh.
In conclusion, the grain sizing of abrasives is an important factor in achieving the desired surface finish and performance for metalworking operations. The correct abrasive grain size range must be determined to ensure efficient and economical metalworking performance. Each abrasive material has its own grain size range, which must be taken into account when selecting the abrasive material for the application.
