Softening in Nanocrystalline Metals Modeling of Grain Growth Induced Creep and Relaxation

2011-04-21
Birkle, Manuel
Gürses, Ercan
Miehe, Christian
A variational multiscale model is presented for grain growth in face-centered cubic nanocrystalline (nc) metals. In parti cular,grain-growth-induced stress so f tening and the resulting r el axation and creep phenomena are addressed. The behavior ofthe polycrystal is described by a conventional Taylor-type averaging scheme in which the grains are treated as two-ph asecomposites consisting of a grain interior phase and a grain boundary affected zone. Furthermore, a grai n growth law thatcaptures the experimentally observed characteristics of the grain coarsening phenomena is proposed. The model is shown toprovide a good descriptio n of the experimentally o b served grain-growth-induced relaxation in nc-copper
82nd Annual Meeting of Gesellschaft für Angewandte Mathematik und Mechanik (GAMM)

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Citation Formats
M. Birkle, E. Gürses, and C. Miehe, “Softening in Nanocrystalline Metals Modeling of Grain Growth Induced Creep and Relaxation,” Graz, Avusturya, 2011, vol. 11, Accessed: 00, 2021. [Online]. Available: http://onlinelibrary.wiley.com/doi/10.1002/pamm.200510143/epdf.