Constitutive modeling of strain rate effects in nanocrystalline and ultrafine grained polycrystals

Date

2011-5

Author

Gürses, Ercan

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We present a variational two-phase constitutive model capable of capturing the enhanced rate sensitivity in nanocrystalline (nc) and ultrafine-grained (ufg) fcc metals. The nc/ufg-material consists of a grain interior phase and a grain boundary affected zone (GBAZ). The behavior of the GBAZ is described by a rate-dependent isotropic porous plasticity model, whereas a rate-independent crystal-plasticity model which accounts for the transition from partial dislocation to full dislocation mediated plasticity is employed for the grain interior. The scale bridging from a single grain to a polycrystal is done by a Taylor-type homogenization. It is shown that the enhanced rate sensitivity caused by the grain size refinement is successfully captured by the proposed model.

Subject Keywords

Constitutive modeling, Rate dependence, Nanocrystals, Crystal plasticity, Grain size

URI

https://hdl.handle.net/11511/28143

Journal

International Journal of Solids and Structures

DOI

https://doi.org/10.1016/j.ijsolstr.2011.02.013

Collections

Department of Aerospace Engineering, Article

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Citation Formats

E. Gürses, “Constitutive modeling of strain rate effects in nanocrystalline and ultrafine grained polycrystals,” International Journal of Solids and Structures, pp. 1610–1616, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/28143.