About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Verification, Calibration, and Validation Approaches for Mechanical Modeling of Metals
|
| Presentation Title |
Modeling BCC Vanadium Tension-Compression Asymmetry With A Non-Schmid HEDM-Informed Crystal Plasticity Model |
| Author(s) |
Harry Smith, Rachel Lim, Jennie Glerum, William Musinski |
| On-Site Speaker (Planned) |
Harry Smith |
| Abstract Scope |
Vanadium alloys are leading candidates for fusion reactor structural materials due to their low neutron activation and favorable mechanical properties. A key challenge in modeling BCC vanadium deformation is the observed tension-compression (T-C) asymmetry in yield stress, arising from the non-planar core structure of ⟨111⟩ screw dislocations — a feature standard Schmid-based crystal plasticity (CP) models cannot capture by construction. High-energy diffraction microscopy (HEDM) and digital image correlation (DIC) experiments were performed on pure vanadium under quasi-static loading at the Cornell High Energy Synchrotron Source (CHESS), providing grain-scale elastic strain tensors and macroscopic stress-strain curves. A Voce CP model calibrated using NSGA-III multi-objective optimization confirms a fundamental inability to reproduce the observed ~9% T-C yield stress asymmetry regardless of parameter choice. A custom non-Schmid power-law Voce model was implemented in LLNL's ExaCMech, incorporating three non-glide stress corrections to the slip driving stress to capture this asymmetry with minimum added complexity. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Modeling and Simulation, Computational Materials Science & Engineering, Mechanical Properties |