Crack propagation in quasicrystals

TL;DR

This study investigates crack propagation in a 2D decagonal quasicrystal, highlighting how atomic environments and quasiperiodic structure influence crack and dislocation behavior, revealing a unique crack propagation mechanism.

Contribution

It introduces a simulation-based analysis of crack dynamics in quasicrystals, emphasizing the role of atomic environments and quasiperiodic structure as obstacles.

Findings

Highly coordinated atomic environments hinder crack and dislocation motion.

A novel crack propagation mechanism involving dislocation emission and phason wall formation.

Quasiperiodic structure influences crack propagation pathways.

Abstract

Crack propagation is studied in a two dimensional decagonal model quasicrystal. The simulations reveal the dominating role of highly coordinated atomic environments as structure intrinsic obstacles for both dislocation motion and crack propagation. For certain overloads, these obstacles and the quasiperiodic nature of the crystal result in a specific crack propagation mechanism: The crack tip emits a dislocation followed by a phason wall, along which the material opens up.