About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Steels in Extreme Conditions
|
| Presentation Title |
Thermal and Irradiation Creep in Pure Metals and Martensitic Steels: A Statistical-Thermodynamic Model for the Coupling of Point-Defect Diffusion With Dislocation Plasticity and Precipitation Damage |
| Author(s) |
Charles Lieou, Brian Wirth |
| On-Site Speaker (Planned) |
Charles Lieou |
| Abstract Scope |
We describe a unified, thermodynamically consistent model for irradiation creep, that combines dislocation glide, the stress-induced preferential absorption (SIPA) of point defects at dislocations, and precipitation damage. Central to the model is the premise that the dynamics of interstitials and vacancies is controlled by temperature, while the dynamics of extended defects, among which dislocations are of prime relevance, is controlled by the configurational degrees of freedom which evolve on a much slower time scale than the kinetic-vibrational degrees of freedom. We present model predictions in comparison to thermal and irradiation creep data in copper, aluminum, and ferritic-martensitic steels HT9 and T91, which suggest that conventional SIPA mechanisms alone are inadequate to explain the pronounced dependence of the irradiation creep rates on stress and temperature, necessitating nontrivial corrections to the SIPA dislocation climb rates. In addition, the implication of tertiary creep data for the modeling of precipitation damage will be discussed. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Modeling and Simulation, Mechanical Properties, Nuclear Materials |