CRYSTALLING AND QUASICRYSTALLINE PHASES IN RAPIDLY SOLIDIFIED Al-Ni ALLOYS

摘要

The formation and structures of stable and metastable phases in splat-cooled Al-Ni alloys with 10-35 at./100 Ni have been investigated by transmission electron microscopy, X-ray diffraction and differential scanning calorimetry. The splats show a three-layer microstructure, the formation of which can be qualitatively explained by the assumption of a high undercooling of the melt prior to solidification. Two metastable phases-monoclonic Al_9Ni_2 and a decagonal phase-were found in the as-quenched Alloys.