Dresden 2026 – wissenschaftliches Programm

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FM: Fachverband Funktionsmaterialien

FM 16: Topical Session: Dislocations in Functional Materials II (joint session MM/FM)

FM 16.5: Vortrag

Mittwoch, 11. März 2026, 17:00–17:15, SCH/A251

Dislocation dynamics in Ni-based superalloys: atomistic simulations and uncertainty quantification — •Geraldine Anis, Thomas Hudson, and Peter Brommer — University of Warwick, Coventry CV4 7AL, UK

Ni-based superalloys exhibit extraordinary strength at high temperatures. This strengthening effect is largely attributed to precipitation strengthening, where dislocations are hindered by precipitates present in their microstructure. In our work, we model dislocation trajectories obtained from Molecular Dynamics (MD) simulations of Ni-Ni₃Al. A reduced model was developed to describe dislocation-interface interactions within this system, which captures important features of the MD dislocation trajectories. The developed model was tested on a representative system and was shown to capture a range of qualitatively different dislocation behaviour. The model parameter distributions were then determined using Differential Evolution Monte Carlo (DE-MC) sampling and a Gaussian process surrogate model. The present approach offers a means of identifying atomistic-scale parameters, which can be used to inform larger length scale simulations of dislocations. Determining parameter distributions using DE-MC means that parameter uncertainties can be propagated through a hierarchy of multiscale models. We illustrate how such uncertainty propagation can be achieved by considering a dislocation mobility law with quantified uncertainties in pure Ni. This work is part of a wider study aiming to model the deformation behaviour of Ni-based superalloys with a focus on quantifying and propagating uncertainties.

Keywords: Dislocations; Molecular dynamics; Bayesian inference; Uncertainty quantification; Ni-base superalloys