Processing and properties of nanophase oxides

Conference · Sun Jan 01 04:00:00 EST 1989

DOI:https://doi.org/10.1557/PROC-155-255· OSTI ID:5363961

Eastman, J A; Liao, Y X; Narayanasamy, A; Siegel, R W

Nanophase oxides (Al{sub 2}O{sub 3}, MgO, ZnO and TiO{sub 2}), with typical grain sizes in the range 2--20 nm, have been synthesized by the condensation of ultrafine particles in a convective inert gas followed by their collection and in-situ consolidation in vacuum at ambient temperature. These new materials, owing to the reduced scale of their grains along with the enhanced cleanliness of their grain boundaries, are found to have significantly improved properties relative to those of their coarser-grained, conventionally-prepared counterparts. Nanophase rutile (TiO{sub 2}) with an initial mean grain diameter of 12 nm, for example, has been found to sinter at 400 to 600{degree}C lower temperatures than conventional rutile powders, without the need for compacting or sintering aids, while retaining a small grain size. Additionally, the importance of the extremely clean surfaces obtained with the gas condensation method has been demonstrated by comparing the sintering behavior of powders with and without air exposure prior to consolidation. The research completed on the processing and properties of nanophase ceramics is reviewed, and the potential for engineering advanced ceramics using the nanophase processing method is discussed. 20 refs., 5 figs.

• Research Organization: Argonne National Lab., IL (USA)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5363961
• Report Number(s): CONF-890426-32; ON: DE90003826
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
ALKALINE EARTH METAL COMPOUNDS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
AMBIENT TEMPERATURE
CERAMICS
CHALCOGENIDES
CRYSTAL STRUCTURE
GRAIN GROWTH
GRAIN SIZE
MAGNESIUM COMPOUNDS
MAGNESIUM OXIDES
MICROSTRUCTURE
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
PROCESSING
SIZE
TEMPERATURE DEPENDENCE
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
ZINC COMPOUNDS
ZINC OXIDES