# Dislocation dynamics formulation for self-climb of dislocation loops by vacancy pipe diffusion

## TL;DR

This paper develops a dislocation dynamics model for the self-climb of prismatic dislocation loops via vacancy pipe diffusion, accurately capturing experimental and atomistic behaviors, and provides a DDD implementation for simulating loop evolution.

## Contribution

It introduces a comprehensive dislocation dynamics formulation for self-climb by pipe diffusion applicable to arbitrary configurations, validated against experiments and atomistic simulations.

## Key findings

- Model accurately describes self-climb behaviors observed experimentally.
- Simulation results show loop evolution, translation, and coalescence.
- Formulation recovers existing models for small circular loops.

## Abstract

It has been shown in experiments that self-climb of prismatic dislocation loops by pipe diffusion plays important roles in their dynamical behaviors, e.g., coarsening of prismatic loops upon annealing, as well as the physical and mechanical properties of materials with irradiation. In this paper, we show that this dislocation dynamics self-climb formulation that we derived in Ref. [1] is able to quantitatively describe the properties of self-climb of prismatic loops that were observed in experiments and atomistic simulations. This dislocation dynamics formulation applies to self-climb by pipe diffusion for any configurations of dislocations. For small circular prismatic loops, our formulation recovers the available models in the literature based on linearly mobility relation driven by the interaction force between the loops and an external stress gradient. We also present DDD implementation method of this self-climb formulation. Simulations performed show evolution, translation and coalescence of prismatic loops as well as prismatic loops driven by an edge dislocation by self-climb motion and the elastic interaction between them. These results are in excellent agreement with available experimental and atomistic results. We have also performed systematic analyses of the behaviors of a prismatic loop under the elastic interaction with an infinite, straight edge dislocation by motions of self-climb and glide.