|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Mechanical Behavior at the Nanoscale III
||W-11: Effect of Texture and Plastic Anisotropy on Stress-strain Response of Nanoscale Aluminum Films
||Ehsan Izadi, Harn Lim, Robert McDonald, Pedro Peralta, Jagannathan Rajagopalan
|On-Site Speaker (Planned)
The grain size dependence of mechanical behavior of nanocrystalline/ultrafine-grained metals is well studied. However, there is limited understanding of the effect of sample texture and the resultant plastic anisotropy on their deformation behavior. We investigated the strain rate-dependent stress-strain response of two 250 nm thick Al films with ~300 nm mean grain size, one with a bicrystalline texture and another with no preferred texture. The bicrystalline film was loaded along two directions that minimize and maximize the plastic anisotropy between the grains. When plastic anisotropy is minimized, the bicrystalline film shows little strain rate sensitivity. In contrast, there is notable strain rate sensitivity when plastic anisotropy is maximized. The non-textured film shows the highest rate sensitivity with flow stress increasing by 95% as strain rate increases from 〖10〗^(-5)/s to 〖10〗^(-2)/s. In situ TEM experiments and a finite element-based crystal plasticity model are used to interpret the underlying mechanisms.
||Planned: A print-only volume