Cleaved surface of i-AlPdMn quasicrystals: Influence of the local temperature elevation at the crack tip on the fracture surface roughness
Résumé
Roughness of i-AlPdMn fracture surfaces are presently analyzed. From the atomic scale up 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. This effect is reported to be responsible for a transition from a perfectly brittle behavior to a nanoductile one.