About this Abstract |
Meeting |
MS&T21: Materials Science & Technology
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Symposium
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Integration between Modeling and Experiments for Crystalline Metals: From Atomistic to Macroscopic Scales III
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Presentation Title |
Full-field Modeling of Vacancy Diffusion in a Crystal Plasticity Framework |
Author(s) |
Aritra Chakraborty, Nathan James Beets, Mariyappan Arul Kumar, Ricardo Lebensohn, Laurent Capolungo |
On-Site Speaker (Planned) |
Aritra Chakraborty |
Abstract Scope |
At high homologous temperature and low-to-moderate stresses vacancy diffusion-mediated plasticity can dominate the creep response of the material. In practice, diffusional flow can occur either by Coble creep (grain boundary diffusion), Nabarro–Herring creep (lattice diffusion) or dislocation creep. In this work, we aim to develop and validate a three-dimensional fully coupled mechanistic diffusion model that can accurately capture these phenomena and predict creep rates observed at such conditions of temperature and stress. Kinematic coupling between dislocation glide and diffusion occurs through the diffusion strain rate tensor that is incorporated into the total strain rate assuming additive decomposition in a small-strain framework. Subsequently, we modulate the different adjustable parameters of the model to gauge their relative influence. Finally, we compare our results to a simplistic one-dimensional diffusional model to determine the importance of having a proper physical description of the diffusion phenomena. |