Internal strains of magnetostrictive origin: Their nature in the static case and behavior in the dynamic regime

Any non uniformity in the spin direction distribution gives rise to internal stresses and strains in a magnetostrictive material. The stresses associated with wall junctions and by extension curved wall boundaries are analysed. It is shown that they are equivalent to the stresses characteristic of disclinations. In the dynamic regime, wall instabilities confined between lattice defects and wall junctions have been observed.