کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
278560 | 1430298 | 2011 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Constitutive modeling of strain rate effects in nanocrystalline and ultrafine grained polycrystals Constitutive modeling of strain rate effects in nanocrystalline and ultrafine grained polycrystals](/preview/png/278560.png)
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.
Journal: International Journal of Solids and Structures - Volume 48, Issue 10, 15 May 2011, Pages 1610–1616