Atomistic and mesoscale modeling of dislocation mobility and plastic strength in FeCr alloy

Anter El-Azab, Purdue University, USA

FeCr alloys are base alloys for candidate ferritic structural materials for fusion reactor applications. In the fusion environment, irradiation may generate local composition fluctuations, precipitates, and dislocation loops, which strongly affect the strength of these materials. Predictive multiscale modeling requires mobility laws that capture how dislocation motion depends on alloy composition and its local variations. We present an atomistically informed phenomenological mobility framework for FeCr that spans the full composition range from Fe to Cr and a wide dislocation character-angle space. The resulting mobility law captures major subsonic glide regimes and enables improved discrete-dislocation simulations of deformation in irradiated ferritic alloys. Time permitting, we will discuss the application of the atomistically computed mobility law in discrete dislocation dynamics simulation of plastic strength of FeCr alloys at various compositions and analyze the synergy between solute hardening and work hardening in this alloy system in the initial yielding regime.

Kieran Edmonds, Mani Muruganandam, Anter El-Azab*
School of Materials Engineering
Purdue University
West Lafayette, IN 47906
* Presenter (aelazab@purdue.edu).