3. Mechanical description: intrinsic dislocations

The grain boundary is a defect in the perfect crystal. Local deformations and stresses are therefore associated with it, which can be described in terms of so-called "structural" dislocations, since they are necessary to explain the disorientation between two crystals.

These dislocations, integral to the structure, are also called "intrinsic". A first dislocation wall model can be used to describe joints of low disorientation , it was then extended to all grain joints