Effect of microstructure on mechanical properties of silicon nitride ceramics. Progress report, April 1, 1984-March 31, 1985. [Sialon-Y/sub 3/Al/sub 5/O/sub 12/]

Technical Report · Thu Nov 01 04:00:00 EST 1984

OSTI ID:6176289

Tien, T Y

Composition in the system Si, Al, Y/N, O was prepared and samples containing 90 wt % ..beta..-SIALON (10 eq.% Al) and 10 wt % Y/sub 3/Al/sub 5/O/sub 12/ was hot pressed to form ceramics with different grain sizes. The grain morphology of the ..beta.. phase are elongated hexagonal prisms and their aspect ratio changes with hot pressing time. Mechanical properties of these hot pressed specimens were tested at room temperature as well as at elevated temperatures. It was found that the strengths as well as the fracture toughness increase with increase of the aspect ratio of the ..beta..-SIALON grains. Grain boundary glass was crystallized by annealing. The crystallization of the grain boundary phase changes the mechanical properties of these ceramics.

• Research Organization: Michigan Univ., Ann Arbor (USA). Dept. of Materials and Metallurgical Engineering
• DOE Contract Number: FG02-84ER45069
• OSTI ID: 6176289
• Report Number(s): DOE/ER/45069-T1; ON: DE85005891
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360203* -- Ceramics
Cermets
& Refractories-- Mechanical Properties
ALUMINATES
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CHALCOGENIDES
CRYSTAL STRUCTURE
FABRICATION
FRACTURE PROPERTIES
GARNETS
HOT PRESSING
MATERIALS WORKING
MECHANICAL PROPERTIES
MICROSTRUCTURE
MINERALS
NITRIDES
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
PRESSING
RESEARCH PROGRAMS
SILICATES
SILICON COMPOUNDS
SILICON NITRIDES
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS