THE MELTING BEHAVIOR OF PASSIVATED NANOCRYSTALLINE ALUMINUM

A nanocomposite Al2O3/Al material has been prepared by consolidation o f nanocrystalline aluminum particles which have been passivated with a n alumina overlayer prior to the compaction step. Nanostructured Al ha s been prepared by the gas phase condensation method. The material has been characterized by XPS (X-ray photoelectron spectroscopy), DSC (di fferential scanning calorimetry), TEM (transmission electron microscop y) and AFM (atomic force microscopy). This study allowed us to demonst rate that the consolidated Al2O3/Al material, although showing a metal lic shine and an ohmic electrical resistivity, presents a microstructu re constituted by Al grains interconnected by a very thin alumina netw ork, which prevents the material from falling apart when heated at tem peratures above the melting point of aluminum. Copyright (C) 1996 Acta Metallurgica Inc.