Highly faceted growth shape of microvoids in icosahedral Al-Mn-Pd

Abstract

Faceted microholes in icosahedral Al-Mn-Pd quasicrystals form by condensation of thermal vacancies, typically during annealing in the temperature range above approximately 700oC. Prolonged annealing at temperatures between 750 and 830oC leads to the growth of large and highly faceted microholes through a classical Ostwald ripening process. The indexing of all facets of such a microhole is presented. The idealized morphology is found to correspond to an icosahedral polyhedron with 302 facets.