Defects at grain boundaries: A coarse-grained, three-dimensional description by the amplitude expansion of the phase-field crystal model

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Marco Salvalaglio - , Technische Universität Dresden (Autor:in)
  • Rainer Backofen - , Technische Universität Dresden (Autor:in)
  • K. R. Elder - , Oakland University (Autor:in)
  • Axel Voigt - , Technische Universität Dresden (Autor:in)

Abstract

We address a three-dimensional, coarse-grained description of dislocation networks at grain boundaries between rotated crystals. The so-called amplitude expansion of the phase-field crystal model is exploited with the aid of finite element method calculations. This approach allows for the description of microscopic features, such as dislocations, while simultaneously being able to describe length scales that are orders of magnitude larger than the lattice spacing. Moreover, it allows for the direct description of extended defects by means of a scalar order parameter. The versatility of this framework is shown by considering both fee and bee lattice symmetries and different rotation axes. First, the specific case of planar, twist gram boundaries is illustrated. The details of the method are reported and the consistency of the results with literature is discussed. Then, the dislocation networks forming at the interface between a spherical, rotated crystal embedded in an unrotated crystalline structure, are shown. Although explicitly accounting for dislocations which lead to an anisotropic shrinkage of the rotated gram, the extension of the spherical grain boundary is found to decrease linearly over time in agreement with the classical theory of grain growth and recent atomistic investigations. It is shown that the results obtained for a system with bee symmetry agree very well with existing results, validating the methodology. Furthermore, fully original results are shown for fee lattice symmetry, revealing the generality of the reported observations.

Details

OriginalspracheEnglisch
Aufsatznummer053804
Seitenumfang10
FachzeitschriftPhysical review materials
Jahrgang2
Ausgabenummer5
PublikationsstatusVeröffentlicht - 30 Mai 2018
Peer-Review-StatusJa
Extern publiziertJa

Externe IDs

Scopus 85059634904
ORCID /0000-0002-4217-0951/work/142237416

Schlagworte

Schlagwörter

  • FCC METALS, DISLOCATION REACTIONS, COMPUTER-SIMULATION, TWIST BOUNDARIES, ENERGY, NETWORKS, GROWTH, MICROSTRUCTURE, DIMENSIONS, INTERFACES