Growth morphologies of quasicrystalline phase in a bulk undercooled Al-Mn-(Si, B) alloy

摘要

The complex method of glass covering, salt denucleating and multiple superheating-cooling has been successfully applied to undercool the melt of bulk Al-Mn-(Si, B) alloy and initiate quasicrystalline phase at an undercooling of 100 K. Growth morphologies of the quasicrystalline phase were characterized by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) . SEM and TEM imagies indicate 5-fold and 3-fold symmetric faceting dendrites, and dendrite elements and polyhedron parti- cles, respectively. The constitution level and relation to m3 5 point group symmetry of growth morphology for the undercooled quasicrystalline phase have been reported for the first time.