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Plasticity of indium antimonide between −176 and 400 °C under hydrostatic pressure / B. Kedjar in Acta materialia, Vol. 58 N° 4 (Fevrier 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 4 (Fevrier 2010) . - pp. 1418–1425 Titre : Plasticity of indium antimonide between −176 and 400 °C under hydrostatic pressure : Part I: Macroscopic aspects of the deformation Type de document : texte imprimé Auteurs : B. Kedjar, Auteur ; L. Thilly, Auteur ; J.-L. Demenet, Auteur Année de publication : 2011 Article en page(s) : pp. 1418–1425 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Semiconductor  Indium  antimonide  Brittle-to-ductile  transition  Compression  Indentation Résumé : Indium antimonide (InSb) single crystals have been plastically deformed between −176 and 400 °C, i.e. below and above the brittle-to-ductile transition temperature situated around 150–160 °C, via the use of microindentation below room temperature (RT) and the Paterson press (compression under gaseous pressure) above RT. The evolution of the macroscopic mechanical data (hardness and critical resolved shear stress) with temperature suggests the existence of three deformation regimes with transitions at Ttr1 = 150 °C and Ttr2 = 20 °C. Ttr1 coincides with the brittle-to-ductile temperature, while Ttr2 may coincide with a transition in the nature of dislocations with dislocations propagating in the glide set above Ttr2 while moving in the shuffle set below Ttr2. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409007538 [article] Plasticity of indium antimonide between −176 and 400 °C under hydrostatic pressure : Part I: Macroscopic aspects of the deformation [texte imprimé] / B. Kedjar, Auteur ; L. Thilly, Auteur ; J.-L. Demenet, Auteur . - 2011 . - pp. 1418–1425. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 4 (Fevrier 2010) . - pp. 1418–1425 Mots-clés : Semiconductor  Indium  antimonide  Brittle-to-ductile  transition  Compression  Indentation Résumé : Indium antimonide (InSb) single crystals have been plastically deformed between −176 and 400 °C, i.e. below and above the brittle-to-ductile transition temperature situated around 150–160 °C, via the use of microindentation below room temperature (RT) and the Paterson press (compression under gaseous pressure) above RT. The evolution of the macroscopic mechanical data (hardness and critical resolved shear stress) with temperature suggests the existence of three deformation regimes with transitions at Ttr1 = 150 °C and Ttr2 = 20 °C. Ttr1 coincides with the brittle-to-ductile temperature, while Ttr2 may coincide with a transition in the nature of dislocations with dislocations propagating in the glide set above Ttr2 while moving in the shuffle set below Ttr2. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409007538

Plasticity of indium antimonide between −176 °C and 400 °C under hydrostatic pressure / B. Kedjar in Acta materialia, Vol. 58 N° 4 (Fevrier 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 4 (Fevrier 2010) . - pp. 1426–1440 Titre : Plasticity of indium antimonide between −176 °C and 400 °C under hydrostatic pressure : Part II: Microscopic aspects of the deformation Type de document : texte imprimé Auteurs : B. Kedjar, Auteur ; L. Thilly, Auteur ; J.-L. Demenet, Auteur Année de publication : 2011 Article en page(s) : pp. 1426–1440 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Semiconductor  Indium  antimonide  Brittle-to-ductile  transition  Transmission  electron  microscopy  Dislocations Résumé : Indium antimonide (InSb) has been plastically deformed over a wide temperature range, from 400 down to −176 °C (see the companion paper: Kedjar B, Thilly L, Demenet JL, Rabier J. Acta Mater 2009) and transmission electron microscopy was used to characterize the deformation microstructures. In the ductile regime, i.e. T > Ttr1 ≈ 150 °C, the crystal deforms via the nucleation and motion of perfect dislocations belonging to the glide set. In the brittle domain, i.e. for T < Ttr1 ≈ 150 °C, two regimes are observed: for Ttr2 ≈ 20 °C < T < Ttr1 ≈ 150 °C, the crystal deformation takes place via the nucleation and glide of dissociated perfect dislocations or only leading partials, while for T < Ttr2 ≈ 20 °C, the crystal deformation proceeds via the nucleation and motion of perfect dislocations belonging to the shuffle set. In view of these observations, the brittle-to-ductile transition (at Ttr1) is confirmed to correspond to a change in the dislocation nature in the glide set, from partial-mediated plasticity at low temperature to perfect-mediated plasticity at high temperature. Another transition is observed at Ttr2 and corresponds to the glide-to-shuffle transition which is observed experimentally for the first time in a III–V compound semiconductor. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409007551 [article] Plasticity of indium antimonide between −176 °C and 400 °C under hydrostatic pressure : Part II: Microscopic aspects of the deformation [texte imprimé] / B. Kedjar, Auteur ; L. Thilly, Auteur ; J.-L. Demenet, Auteur . - 2011 . - pp. 1426–1440. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 4 (Fevrier 2010) . - pp. 1426–1440 Mots-clés : Semiconductor  Indium  antimonide  Brittle-to-ductile  transition  Transmission  electron  microscopy  Dislocations Résumé : Indium antimonide (InSb) has been plastically deformed over a wide temperature range, from 400 down to −176 °C (see the companion paper: Kedjar B, Thilly L, Demenet JL, Rabier J. Acta Mater 2009) and transmission electron microscopy was used to characterize the deformation microstructures. In the ductile regime, i.e. T > Ttr1 ≈ 150 °C, the crystal deforms via the nucleation and motion of perfect dislocations belonging to the glide set. In the brittle domain, i.e. for T < Ttr1 ≈ 150 °C, two regimes are observed: for Ttr2 ≈ 20 °C < T < Ttr1 ≈ 150 °C, the crystal deformation takes place via the nucleation and glide of dissociated perfect dislocations or only leading partials, while for T < Ttr2 ≈ 20 °C, the crystal deformation proceeds via the nucleation and motion of perfect dislocations belonging to the shuffle set. In view of these observations, the brittle-to-ductile transition (at Ttr1) is confirmed to correspond to a change in the dislocation nature in the glide set, from partial-mediated plasticity at low temperature to perfect-mediated plasticity at high temperature. Another transition is observed at Ttr2 and corresponds to the glide-to-shuffle transition which is observed experimentally for the first time in a III–V compound semiconductor. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409007551

Structure, shear resistance and interaction with point defects of interfaces in Cu–Nb nanocomposites synthesized by severe plastic deformation / M.J. Demkowicz in Acta materialia, Vol. 59 N° 20 (Décembre 2011) 

Public ISBD [article]  in Acta materialia > Vol. 59 N° 20 (Décembre 2011) . - pp. 7744–7756 Titre : Structure, shear resistance and interaction with point defects of interfaces in Cu–Nb nanocomposites synthesized by severe plastic deformation Type de document : texte imprimé Auteurs : M.J. Demkowicz, Auteur ; L. Thilly, Auteur Année de publication : 2012 Article en page(s) : pp. 7744–7756 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Severe  plastic  deformation  Nanocomposite  Interface  structure  Slip  Molecular  dynamics Résumé : Atomistic modeling is used to investigate the shear resistance and interaction with point defects of a Cu–Nb interface found in nanocomposites synthesized by severe plastic deformation. The shear resistance of this interface is highly anisotropic: in one direction shearing occurs at stresses <1200 MPa, while in the other it does not occur at all. The binding energy of vacancies, interstitials and He impurities to this interface depends sensitively on the binding location, but there is no point defect delocalization, nor does this interface contain any constitutional defects. These behaviors are markedly dissimilar from a different Cu–Nb interface found in magnetron sputtered composites. The dissimilarities may, however, be explained by quantitative differences in the detailed structure of these two interfaces. ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645411006318 [article] Structure, shear resistance and interaction with point defects of interfaces in Cu–Nb nanocomposites synthesized by severe plastic deformation [texte imprimé] / M.J. Demkowicz, Auteur ; L. Thilly, Auteur . - 2012 . - pp. 7744–7756. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 59 N° 20 (Décembre 2011) . - pp. 7744–7756 Mots-clés : Severe  plastic  deformation  Nanocomposite  Interface  structure  Slip  Molecular  dynamics Résumé : Atomistic modeling is used to investigate the shear resistance and interaction with point defects of a Cu–Nb interface found in nanocomposites synthesized by severe plastic deformation. The shear resistance of this interface is highly anisotropic: in one direction shearing occurs at stresses <1200 MPa, while in the other it does not occur at all. The binding energy of vacancies, interstitials and He impurities to this interface depends sensitively on the binding location, but there is no point defect delocalization, nor does this interface contain any constitutional defects. These behaviors are markedly dissimilar from a different Cu–Nb interface found in magnetron sputtered composites. The dissimilarities may, however, be explained by quantitative differences in the detailed structure of these two interfaces. ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645411006318

Thermal stability of nanocomposite metals / J. B. Dubois in Acta materialia, Vol. 58 N° 19 (Novembre 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 19 (Novembre 2010) . - pp. 6504–6512 Titre : Thermal stability of nanocomposite metals : In situ observation of anomalous residual stress relaxation during annealing under synchrotron radiation Type de document : texte imprimé Auteurs : J. B. Dubois, Auteur ; L. Thilly, Auteur ; P.O. Renault, Auteur Année de publication : 2011 Article en page(s) : pp. 6504–6512 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Nanostructures  In  situ  annealing  Residual  stresses  X-ray  diffraction  Synchrotron Résumé : The thermal stability of nanocomposite metals (a nanostructured copper matrix embedding niobium nanotubes) is investigated via time-resolved in situ annealing under synchrotron high-energy X-rays. The diffraction peak profile analysis demonstrates that internal-stress relaxation begins in the Nb nanotubes at a temperature far below the bulk recrystallization temperature and follows size-specific regimes originating from a proximity effect with the nanostructured Cu matrix: the increased Cu–Nb interface surface disrupts internal-stress relaxation processes, confirming the larger thermal resistance of nanostructured materials. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645410005276 [article] Thermal stability of nanocomposite metals : In situ observation of anomalous residual stress relaxation during annealing under synchrotron radiation [texte imprimé] / J. B. Dubois, Auteur ; L. Thilly, Auteur ; P.O. Renault, Auteur . - 2011 . - pp. 6504–6512. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 19 (Novembre 2010) . - pp. 6504–6512 Mots-clés : Nanostructures  In  situ  annealing  Residual  stresses  X-ray  diffraction  Synchrotron Résumé : The thermal stability of nanocomposite metals (a nanostructured copper matrix embedding niobium nanotubes) is investigated via time-resolved in situ annealing under synchrotron high-energy X-rays. The diffraction peak profile analysis demonstrates that internal-stress relaxation begins in the Nb nanotubes at a temperature far below the bulk recrystallization temperature and follows size-specific regimes originating from a proximity effect with the nanostructured Cu matrix: the increased Cu–Nb interface surface disrupts internal-stress relaxation processes, confirming the larger thermal resistance of nanostructured materials. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645410005276