A MODEL OF DEFORMATION BANDS FORMATION

摘要

The formation of deformation bands with the typically alternating sign of the misorientation across their boundaries is explained within the framework of continuum mechanics. For a crystalline solid it is less energetically costly to be fragmented in bands deformed by a reduced number of slip systems and fitted together by local reorientations than to be deformed by more energetically costly homogeneous multislip. A model of an infinite crystal deformed by symmetric double slip in plane strain compression is considered. The orientation and the width of the bands result from the competition between two tendencies: the internal and dissipative energy tend to set up an extreme band orientation and reduce their width to zero, whereas the energy needed to form boundaries and to overcome the bowing stress opposes this tendency.