About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Microstructure-Sensitive Modeling Across Length Scales: An MPMD/SMD Symposium in Honor of David L. McDowell
|
| Presentation Title |
Mechanistic Origin of Size Effects in Metals |
| Author(s) |
Arya Dipajaya Nugraha, Gustavo Castelluccio |
| On-Site Speaker (Planned) |
Gustavo Castelluccio |
| Abstract Scope |
Multiple mechanistic theories have been proposed to explain the role of crystal structure, composition, and loading conditions on the macroscopic mechanical response of metallic materials. However, mechanistic explanations for size effects remain elusive in the literature, as most modelling efforts are based on phenomenological formulations. These theories often depend on fitted parameters or incomplete physical assumptions, limiting their predictive accuracy beyond calibration domains.
This presentation investigates the mechanisms responsible for size effects in metallic materials, focusing on five key contributions: restriction of dislocation mean free path, size-induced back stress, influence of initial dislocation length, size-sensitive structures, and anelasticity. The approach avoids phenomenological parameters and uses a dislocation structure-based CPFEM applicable across single-phase FCC materials without recalibration. The model is validated against materials of various sizes and loading conditions (monotonic, cyclic, bending). It also provides a physical foundation for strain gradient theories and helps clarify experimentally observed size-related anomalies. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Modeling and Simulation, Other |