Residual stresses can be characterized by the scale at which they exist within a material. Stresses that occur over long distances within a material are referred to as macro stresses. Stresses that exist only locally (either between grains or inside a grain) are called micro stresses. The total residual stress at a given location inside a material is the sum of all three types of stresses.
The average residual stress over a group of grains (crystals) in a material (~mm scale).
Residual stress variations between grains; variations may result from different phases in the material.
Residual stress within one grain; variations may result from dislocations or crystalline defects.
