Wear 
Loss of material from a plate surface subjected to repeated mechanical contacts.

Surface Damage
Surface damage is the result of mechanical contacts between abrasive material and the plate. The surface damages appears as micro-cracking, plastic deformation or micro-cutting and surface transformation.

Abrasion
Surface damage and loss of material on a plate surface arising from  penetrating sharp edges or points on abrasive bodies.

Wear Situation
Wear situation describes the movement of the abrasive material on the plate. Sliding, impact and squeezing wear are three common wear situations.

Abrasive Material 
Materials causing penetration, surface damage and wear on another surface.

Hardness
A solid material’s ability to withstand penetration from a pointed body.

Relative Hardness
The hardness relation between the abrasive material and the plate. Measured in Vickers, HV.

Cutting
A specific surface damage caused by abrasive material cutting micro-chips out of the plate surface.

Plastic Deformation
A specific surface damage caused by abrasive material penetrating and ploughing the plate to which the plate surface permanently deforms. Repeated plastic deformation leads to loss of surface material… wear!.

Sliding Wear
Wear caused by abrasive bodies sliding on a plate.

Abrasive Impact
Wear caused by abrasive bodies impacting a plate surface. Different angles of incidence occurs . The surface damages are less dependent on the hardness of the abrasive body. “Plastic deformation" often appears.

Particle Erosion
 A small abrasive particle impacting a plate surface at a high velocity. The surface damage is strongly dependent of the hardness and sharpness of the abrasive particle. The damaged surface have indentations like lip formation and/or plastic deformations.

Angle of Incidence 
Is the angle between the abrasive body’s direction of motion and the plate surface. The angle of incidence strongly influences the erosive wear.

Squeezing wear
Occurs when the abrasive material is squeezed between two rigid surfaces. The abrasive particles have a sliding and rotating motion and may sometimes only be indented into surfaces.

Mohs Hardness 
A method to rank the hardness of minerals and rocks. The method is applied by scratching different materials against each other. The softer material will be scratched by the harder material. As an example, diamond is the hardest material and has Mohs number 10 while calcite is softer and has Mohs number 3.