Eshelbian mechanics of novel materials: Quasicrystals

TL;DR

This paper develops the Eshelbian configurational mechanics framework for quasicrystals, deriving key quantities and integrals related to dislocations, and providing explicit formulas for specific crystal structures, enhancing understanding of their mechanical behavior.

Contribution

It introduces a comprehensive Eshelbian mechanics framework for quasicrystals, including new derivations of integrals and forces specific to their unique structure.

Findings

Derived Eshelby stress tensor and configurational forces for quasicrystals.

Explicit formulas for $J$-, $M$-, and $L$-integrals in hexagonal quasicrystals.

Connected integrals to dislocation interactions and torque in quasicrystals.

Abstract

In this work, the so-called Eshelbian or configurational mechanics of quasicrystals is presented. Quasicrystals are considered as a prototype of novel materials. Material balance laws for quasicrystalline materials with dislocations are derived in the framework of generalized incompatible elasticity theory of quasicrystals. Translations, scaling transformations as well as rotations are examined; the latter presents particular interest due to the quasicrystalline structure. This derivation provides important quantities of the Eshelbian mechanics, as the Eshelby stress tensor, the scaling flux vector, the angular momentum tensor, the configurational forces (Peach-Koehler force, Cherepanov force, inhomogeneity force or Eshelby force), the configurational work and the configurational vector moments for dislocations in quasicrystals. The corresponding $J$-, $M$-, and $L$-integrals for dislocation loops and straight dislocations in quasicrystals are derived and discussed. Moreover, the explicit formulas of the $J$-, $M$-, and $L$-integrals for parallel screw dislocations in one-dimensional hexagonal quasicrystals are obtained. Through this derivation, the physical interpretation of the $J$-, $M$-, and $L$-integrals for dislocations in quasicrystals is revealed and their connection to the Peach-Koehler force, the interaction energy and the rotational vector moment (torque) of dislocations in quasicrystals is established.