Simulations of cubic-tetragonal ferroelastics

TL;DR

This paper uses large-scale numerical simulations to explore domain patterns in cubic-tetragonal ferroelastics, revealing complex banded structures and transient features consistent with experimental observations.

Contribution

It provides detailed simulation results of domain patterns in cubic-tetragonal ferroelastics, including the formation of multiply banded structures and transient phenomena, advancing understanding of their microstructure.

Findings

Most late-stage patterns are multiply banded with all three variants.

Two primary variants form broad bands, while the third forms narrow secondary bands.

Transient structures show features observed in experiments.

Abstract

We study domain patterns in cubic-tetragonal ferroelastics by solving numerically equations of motion derived from a Landau model of the phase transition, including dissipative stresses. Our system sizes, of up to 256^3 points, are large enough to reveal many structures observed experimentally. Most patterns found at late stages in the relaxation are multiply banded; all three tetragonal variants appear, but inequivalently. Two of the variants form broad primary bands; the third intrudes into the others to form narrow secondary bands with the hosts. On colliding with walls between the primary variants, the third either terminates or forms a chevron. The multipy banded patterns, with the two domain sizes, the chevrons and the terminations, are seen in the microscopy of zirconia and other cubic-tetragonal ferroelastics. We examine also transient structures obtained much earlier in the relaxation; these show the above features and others also observed in experiment.