Determination of the characteristic dissipation in the propagation of a lattice transition front|Determination de la dissipation caracteristique dans la propagation d'un front de recristallisation

We study the displacement of the boundary between the two grains of an ideal two-dimensional bicrystal having a hexagonal lattice within the plane. The boundary we deal with is a discontinuity straight line for the lattice orientation function that may move at a different velocity from the underlying matter; hence dissipation occurs, eventually equal to the rate of released energy. We estimate the characteristic dissipation in the propagation of the discontinuity.