If the contact interface between two surfaces has interlocking of an inclined or curved contact, ploughing
takes place in sliding. As a result of ploughing, a certain volume of surface material is removed and an
abrasive groove is formed on the weaker surface. This type of wear is called abrasive wear.
Here, we assume a single contact point model where a hard, sharp abrasive is indented against the flat
surface and forms a groove on it by ploughing. When wearing material has a ductile property, a ribbonlike,
long wear particle is generated by the mechanism of microcutting. In the case of brittle material,
however, a wear particle is generated by a crack propagation (Evans and Marshall, 1981). These differences
are summarized schematically in Figures 7.9a and b.