Cleaved surface of i-AlPdMn quasicrystals: Influence of the local temperature elevation at the crack tip on the fracture surface roughness

TL;DR

This study analyzes the fracture surface roughness of i-AlPdMn quasicrystals, revealing how local temperature elevation at the crack tip influences the transition from brittle to nanoductile behavior through damage mechanisms at the atomic scale.

Contribution

It demonstrates for the first time that local temperature elevation at the crack tip causes a transition from brittle to nanoductile fracture in quasicrystals.

Findings

Surface roughness exhibits scaling properties similar to disordered materials.

Damage mechanisms occur within a 2-3 nm zone at the crack tip.

Local temperature elevation influences fracture behavior transition.

Abstract

Roughness of i-AlPdMn cleaved surfaces are presently analysed. From the atomic scale to 2-3 nm, they are shown to exhibit scaling properties hiding the cluster (0.45 nm) aperiodic structure. These properties are quantitatively similar to those observed on various disordered materials, albeit on other ranges of length scales. These properties are interpreted as the signature of damage mechanisms occurring within a 2-3 nm wide zone at the crack tip. The size of this process zone finds its origin in the local temperature elevation at the crack tip. For the very first time, this effect is reported to be responsible for a transition from a perfectly brittle behavior to a nanoductile one.