FUNDAMENTAL WEAR MODES
Wear Mechanism
Physical/Chemical Processes
Adhesive Wear
If the contact interface between two surfaces has enough adhesive
bonding strength to resist relative sliding, large plastic deformation
caused by displocation is introduced. As a result of the deformation,
a crack is initiated and is propogated.
Abrasive Wear
If the contact between two surfaces has interlocking of an inclined or
curved contact, ploughing takes place as the surfaces slide. As a
result of ploughing, a certain volume of surface material is removed
and an abrasive groove is formed on the weaker surface.
Fatigue Wear
Repeated cycles of contact are not necessary in adhesive and abrasive
wear for the generation of wear particles. There are other cases of
wear where a certain number of repeated contacts are essential for
the generation of wear particles. Wear generated after such contact
cycles is called fatigue wear.
Corrosive Wear
When sliding takes place, especially in corrosive liquids or gases,
reaction products are formed on the surface by chemical or
electrochemical interactions. If these reaction products adhere
strongly to the surface and behave like the bulk material, the wear
mechanism should be almost the same as that of the bulk material.
Therefore, wear is quite different from that of the bulk material, and
is dominated by the reaction products formed by the interaction of
solid materials with the corrosive environment. This kind of
tribomechanical wear accelerated by corrosive media is called
corrosive wear.