|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Advanced Characterization Techniques for Quantifying and Modeling Deformation Mechanisms
||Physics Based-crystal Plasticity Modeling of Single Crystal Niobium
||Tias Maiti, Philip Eisenlohr, Di Kang, Thomas Bieler
|On-Site Speaker (Planned)
Constitutive models based on thermally-activated stress-assisted dislocation kinetics have been successful in predicting deformation behavior of crystalline materials, particularly in face-centered cubic (FCC) metals. In body-centered cubic (BCC) metals success has been more or less limited, owing to ill-defined nature of slip planes and non-planar spreading of 1/2<111> screw dislocation cores leading to a strong dependence of flow stress on temperature and strain-rate. We present high resolution full-field crystal plasticity deformation simulations of single crystal Niobium under tensile and compressive loading with an emphasis on multi-stage hardening, orientation dependence, and the violation of non-Schmid behavior. A physics based material model with atomistically derived parameters for non-Schmid flow rule and kink-pair mechanism (kink-pair nucleation and their lateral propagation) is used for this purpose. The results are then compared with in-situ measurements under tensile and compressive loading.
||Planned: Supplemental Proceedings volume