Concepts of wear processes from tribology
This chapter provides a description and classification of the wear processes and mechanisms. It shows that the wear of tools during rock cutting is a result of processes very different from those occurring in pumps or pipes. To describe the wear process, which is defined as the type of action exercised on the solid body, use can be made of concepts laid down in DIN 50 320, a German standard. Tribology embraces the scientific investigation of all types of friction, lubrication and wear and the technological application of this knowledge. The classification is based on the type of motion that is occurring and the types of phases involved in the wear process. Zum Gahr explains that, although a large number of wear mechanisms are described in literature, these can all be brought back to four basic mechanisms. These four mechanisms are described as well in DIN 50 320: adhesive wear, abrasion, surface fatigue and tribochemical reaction.