Probing the dynamics of quasicrystal growth using synchrotron live imaging

TL;DR

This study uses synchrotron live imaging to investigate the growth dynamics of icosahedral AlPdMn quasicrystals, revealing facetted growth, the impact of interface kinetics, and the role of aluminum rejection in grain evolution.

Contribution

It provides the first detailed visualization of quasicrystal growth mechanisms and highlights the influence of interface kinetics and aluminum rejection on solidification.

Findings

Facetted growth occurs via tangential ledge motion.

Interface kinetics significantly affect nucleation and grain growth.

Aluminum rejection influences grain poisoning and fluid flow.

Abstract

The dynamics of quasicrystal growth remains an unsolved problem in condensed matter. By means of synchrotron live imaging, facetted growth proceeding by the tangential motion of ledges at the solid-melt interface is clearly evidenced all along the solidification of icosahedral AlPdMn quasicrystals. The effect of interface kinetics is significant so that nucleation and free growth of new facetted grains occur in the melt when the solidification rate is increased. The evolution of these grains is explained in details, which reveals the crucial role of aluminum rejection, both in the poisoning of grain growth and driving fluid flow.