Low-Temperature High-Pressure Consolidation of Amorphous Al2O3–15 mol% Y2O3
Abstract:This study examined pressure consolidation of amorphous Al2O3–15 mol% Y2O3 powders prepared by co-precipitation and spray pyrolysis. The two amorphous powders had similar true densities and crystallization sequences. Uniaxial hot pressing was carried out at 450°–600°C with a moderate pressure of 750 MPa. The co-precipitated powder could be hot pressed to a maximum relative density of 98% and remained amorphous. Pressure adversely affected the densification of the spray-pyrolyzed powder by favoring an early crystallization of -Al2O3 phase at 580°C. Plastic deformation of the amorphous phase is believed to be responsible for the large densification of the amorphous powders.
Document Type: Research Article
Affiliations: Department of Metallurgy, Indian Institute of Science, Bangalore 560 012, India
Publication date: 2005-10-01