Analysis of dodecahedral voids in single-quasicrystalline Al-Pd-Mn by scanning electron microscopy and Auger electron spectroscopy

Scanning electron microscopy and microprobe Auger electron spectroscopy were used for characterizing the morphology and the surface composition of voids in the bulk of icosahedral Al-Pd-Mn single-quasicrystals. The samples were prepared by in-situ cleavage fracture in the ultra-high vacuum. The void images could be explained on the basis of an irregular dodecahedral shape. The void facets were parallel to five-fold quasicrystal lattice planes. The surfaces of the voids grown under close-to-equilibrium conditions during the cooling of the quasicrystal were depleted in Mn and enriched in Pd with respect to the bulk.