High toughness alumina/aluminate: The role of hetero-interfaces

Book · Sun Dec 01 04:00:00 EST 1996

OSTI ID:400628

Brito, M E; Yasuoka, M; Kanzaki, S ^[1]

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1. National Industrial Research Inst. of Nagoya (Japan)

Silica doped alumina/aluminate materials present a combination of high strength and high toughness not achieved before in other alumina systems, except for transformation toughened alumina. The authors have associated the increase in toughness to crack bridging by anisotropically grown alumina grains with concurrent interfacial debonding of these grains. A HREM study of grain boundaries and hetero-interface structures in this material shows the absence of amorphous phases at grain boundaries. Local Auger electron analysis of fractured surfaces revealed the coexistence of Si and La at the grain facets exposed by the noticeable intergranular fracture mode of this material. It is concluded that a certain and important degree of boundaries weakness is related to both presence of Si at the interfaces and existence of alumina/aluminate hetero-interfaces.

• OSTI ID: 400628
• Report Number(s): CONF-951155--; ISBN 1-55899-312-6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM OXIDES
AUGER ELECTRON SPECTROSCOPY
COMPOSITE MATERIALS
DOPED MATERIALS
ELECTRON DIFFRACTION
EMISSION SPECTROSCOPY
EXPERIMENTAL DATA
FRACTOGRAPHY
GRAIN BOUNDARIES
LANTHANUM OXIDES
MICROSTRUCTURE
SAMPLE PREPARATION
SCANNING ELECTRON MICROSCOPY
SILICA
SINTERING
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION
X-RAY SPECTROSCOPY