Fabrication, phase transformation studies and characterization of SiC-AlN-Al sub 2 OC ceramics

Technical Report · Wed Jan 03 04:00:00 EST 1990

DOI:https://doi.org/10.2172/5053027· OSTI ID:5053027

Virkar, A. V.

The research effort conducted to date had two specific objectives: (1) to determine phase relations and phase transformations in SiC-AlN, AlN-Al{sub 2}OC, and SiC-Al{sub 2}OC pseudobinary systems and in SiC-AlN-Al{sub 2}OC pseudoternary system, and (2) to determine the effects of composition and microstructure on high temperature creep deformation properties. Published literature in this field shows that SiC, AlN, and Al{sub 2}OC exhibit extensive solid solubility. Subsequently, our work showed that the solid solution undergoes phase separation upon annealing. In particular, phase separation in the SiC-AlN and AlN-Al{sub 2}OC systems by the formation of modulations (by spinodal decomposition) as well as by cellular precipitation was documented. The demonstration of diffusional phase transformations in these covalently bonded refractory structural ceramics in itself is interesting. More importantly, however, is the potential for establishing property/microstructure relationships in this system. 41 refs., 4 figs.

• Research Organization: Utah Univ., Salt Lake City, UT (USA). Dept. of Materials Science and Engineering
• Sponsoring Organization: DOE/ER
• DOE Contract Number: FG02-87ER45286
• OSTI ID: 5053027
• Report Number(s): DOE/ER/45286-3; ON: DE90006591
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201 -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360203 -- Ceramics
Cermets
& Refractories-- Mechanical Properties
ALUMINIUM CARBIDES
ALUMINIUM COMPOUNDS
ALUMINIUM NITRIDES
ALUMINIUM OXIDES
CARBIDES
CARBON COMPOUNDS
CHALCOGENIDES
CREEP
CRYSTAL STRUCTURE
DOCUMENT TYPES
FABRICATION
GRAIN SIZE
MECHANICAL PROPERTIES
MICROSTRUCTURE
NITRIDES
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PNICTIDES
PROGRESS REPORT
SILICON CARBIDES
SILICON COMPOUNDS
SIZE
TEMPERATURE DEPENDENCE