Elastic theory of icosahedral quasicrystals – application to straight dislocations
نویسنده
چکیده
In quasicrystals, there are not only conventional, but also phason displacement fields and associated Burgers vectors. We have calculated approximate solutions for the elastic fields induced by two-, threeand fivefold straight screwand edge-dislocations in infinite icosahedral quasicrystals by means of a generalized perturbation method. Starting from the solution for elastic isotropy in phonon and phason spaces, corrections of higher order reflect the two-, threeand fivefold symmetry of the elastic fields surrounding screw dislocations. The fields of special edge dislocations display characteristic symmetries also, which can be seen from the contributions of all orders. PACS. 61.44.Br Quasicrystals – 61.72.Lk Linear defects: dislocations, disclinations – 62.20.Dc Elasticity, elastic constants
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