Abrasives
The most important property of an abrasive is its hardness. For abrasive grains to effectively cut, they must be significantly harder than the workpiece material. They can be grouped based on their hardness into two categories: conventional abrasives and superabrasives.
Conventional abrasive materials have been used by man since the advent of machining. They are made of materials that exist naturally on Earth, and they are abundant and cheap. Conventional abrasives can suitably machine most materials.
Superabrasives are much harder than conventional abrasives. Since they are much more expensive, they are used when conventional abrasives will not suffice.
Common abrasives are listed below.
Read more about this topic: Abrasive Machining