Documents disponibles écrits par cet auteur

Strain hardening and heterogeneous deformation during twinning in Hadfield steel / C. Efstathiou in Acta materialia, Vol. 58 N° 5 (Mars 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 5 (Mars 2010) . - pp. 1479–1488 Titre : Strain hardening and heterogeneous deformation during twinning in Hadfield steel Type de document : texte imprimé Auteurs : C. Efstathiou, Auteur ; H. Sehitoglu, Auteur Année de publication : 2011 Article en page(s) : pp. 1479–1488 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Manganese  steel  Secondary  twinning  Digital  image  correlation  (DIC)  Low  stacking  fault  energy  Fcc  alloy Résumé : We identify the role of deformation twinning and twin–twin intersections on the strain hardening behavior of Hadfield steel single crystals using strain field measurements. In situ and ex situ strain field measurements resolved at micrometer length scales are obtained using digital image correlation. Ex situ measurements reveal that macroscopic twin-bands, which are composed of a mixture of fine twin-lamella and matrix material, generate approximately 30% axial strain. This measurement is comparable to strain predictions based on twinning crystallography. In situ measurements reveal that primary and secondary twins may nucleate simultaneously, but the primary twin-system remains predominantly active with increased deformation. The intersection of primary and secondary twin-systems was directly linked to an increase in the strain hardening response. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409007575 [article] Strain hardening and heterogeneous deformation during twinning in Hadfield steel [texte imprimé] / C. Efstathiou, Auteur ; H. Sehitoglu, Auteur . - 2011 . - pp. 1479–1488. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 5 (Mars 2010) . - pp. 1479–1488 Mots-clés : Manganese  steel  Secondary  twinning  Digital  image  correlation  (DIC)  Low  stacking  fault  energy  Fcc  alloy Résumé : We identify the role of deformation twinning and twin–twin intersections on the strain hardening behavior of Hadfield steel single crystals using strain field measurements. In situ and ex situ strain field measurements resolved at micrometer length scales are obtained using digital image correlation. Ex situ measurements reveal that macroscopic twin-bands, which are composed of a mixture of fine twin-lamella and matrix material, generate approximately 30% axial strain. This measurement is comparable to strain predictions based on twinning crystallography. In situ measurements reveal that primary and secondary twins may nucleate simultaneously, but the primary twin-system remains predominantly active with increased deformation. The intersection of primary and secondary twin-systems was directly linked to an increase in the strain hardening response. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409007575