Mechanical properties and microstructure of pressureless sintered duophase sialon

Conference · Tue Jan 01 04:00:00 EST 1991

OSTI ID:5338175

Lee, Ran-Rong; Novich, B E; Franks, G; Quellette, D ^[1]; Ferber, M K; Hubbard, C R; More, K ^[2]

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1. Ceramics Process Systems Corp., Milford, MA (United States)
2. Oak Ridge National Lab., TN (United States)

Duophase ({alpha}{prime}/{beta}{prime}) sialon is being developed for ceramic engine applications by using the Quickset{trademark} injection molding process, followed by pressureless sintering and a thermal treatment. The sialon had an average four-point flexural strength of 670 MPa at room temperature and 490 MPa at 1370{degree}C. It survived the flexural stress rupture test at 1300{degree}C and 340 MPa for 190 hours. X-ray diffraction (XRD) and transmission electron microscopy (TEM) characterization showed that crystallization of the grain boundary phase improved the high temperature flexural strength of this sialon material. The creep behavior was also found to be affected by the crystallized grain boundary phases. The formation of a yttrium aluminum garnet (YAG) phase and elongated grains yielded better creep resistance. The correlation between mechanical properties and microstructure is discussed. 13 refs., 7 figs.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5338175
• Report Number(s): CONF-910617-4; ON: DE92000043
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360203* -- Ceramics
Cermets
& Refractories-- Mechanical Properties
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CHALCOGENIDES
COHERENT SCATTERING
CREEP
CRYSTAL STRUCTURE
DIFFRACTION
FLEXURAL STRENGTH
GRAIN BOUNDARIES
HARDNESS
MECHANICAL PROPERTIES
MICROSTRUCTURE
NITRIDES
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
PNICTIDES
SCATTERING
SILICON COMPOUNDS
SILICON NITRIDES
THERMODYNAMIC PROPERTIES
X-RAY DIFFRACTION