Defective twin boundaries in nanotwinned metals

TitleDefective twin boundaries in nanotwinned metals
Publication TypeJournal Article
Year of Publication2013
AuthorsWang YM, Sansoz F, LaGrange T, Ott RT, Marian J, Barbee TW, Hamza AV
Journal TitleNature Materials
Date Published08
Type of ArticleArticle
ISBN Number1476-1122
Accession NumberWOS:000322119100013
Keywordsanisotropy, copper, deformation mechanisms, maximum strength, nanoscale, ORIENTATION, PLASTIC-DEFORMATION

Coherent twin boundaries (CTBs) are widely described, both theoretically and experimentally, as perfect interfaces that play a significant role in a variety of materials. Although the ability of CTBs in strengthening, maintaining the ductility and minimizing the electron scattering is well documented(1-3), most of our understanding of the origin of these properties relies on perfect-interface assumptions. Here we report experiments and simulations demonstrating that as-grown CTBs in nanotwinned copper are inherently defective with kink-like steps and curvature, and that these imperfections consist of incoherent segments and partial dislocations. We further show that these defects play a crucial role in the deformation mechanisms and mechanical behaviour of nanotwinned copper. Our findings offer a view of the structure of CTBs that is largely different from that in the literature(2,4,5), and underscore the significance of imperfections in nanotwin-strengthened materials.

URL<Go to ISI>://WOS:000322119100013