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Coupling of grain boundary sliding and migration within the range of boundary specialness / A.D. Sheikh-Ali in Acta materialia, Vol. 58 N° 19 (Novembre 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 19 (Novembre 2010) . - pp. 6249–6255 Titre : Coupling of grain boundary sliding and migration within the range of boundary specialness Type de document : texte imprimé Auteurs : A.D. Sheikh-Ali, Auteur Année de publication : 2011 Article en page(s) : pp. 6249–6255 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Grain  boundary  sliding  Grain  boundary  migration  High-temperature  deformation  Coincidence  site  lattice  Grain  boundary  dislocation Résumé : Stress-induced behavior of high-angle near-coincidence symmetric tilt boundaries has been examined in bicrystal specimens of zinc. Parameters of coupling between boundary sliding and migration were determined. The angular deviation from the coincidence misorientation within the range of boundary specialness has a noticeable effect on the sliding-to-migration ratio, called “coupling factor”. Mechanisms of coupled boundary sliding and migration based on the motion of edge-type extrinsic and intrinsic grain boundary dislocations are discussed. It has been demonstrated that the observed alteration of the coupling factor with the change in boundary misorientation is due to the change of the parameters of extrinsic secondary grain boundary dislocations. The obtained results have also shown the limitation of the coincidence site lattice/displacement shift complete lattice model for the quantitative description of the structure of near-coincidence boundaries. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645410004878 [article] Coupling of grain boundary sliding and migration within the range of boundary specialness [texte imprimé] / A.D. Sheikh-Ali, Auteur . - 2011 . - pp. 6249–6255. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 19 (Novembre 2010) . - pp. 6249–6255 Mots-clés : Grain  boundary  sliding  Grain  boundary  migration  High-temperature  deformation  Coincidence  site  lattice  Grain  boundary  dislocation Résumé : Stress-induced behavior of high-angle near-coincidence symmetric tilt boundaries has been examined in bicrystal specimens of zinc. Parameters of coupling between boundary sliding and migration were determined. The angular deviation from the coincidence misorientation within the range of boundary specialness has a noticeable effect on the sliding-to-migration ratio, called “coupling factor”. Mechanisms of coupled boundary sliding and migration based on the motion of edge-type extrinsic and intrinsic grain boundary dislocations are discussed. It has been demonstrated that the observed alteration of the coupling factor with the change in boundary misorientation is due to the change of the parameters of extrinsic secondary grain boundary dislocations. The obtained results have also shown the limitation of the coincidence site lattice/displacement shift complete lattice model for the quantitative description of the structure of near-coincidence boundaries. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645410004878