Strength of hot isostatically pressed and sintered reaction bonded silicon nitrides containing Y/sub 2/O/sub 3/

Technical Report · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6292296

Sanders, W A; Mieskowski, D M

The hot isostatic pressing of reaction bonded Si/sub 3/N/sub 4/ containing Y/sub 2/O/sub 3/ produced specimens with greater room temperature strengths than those by high pressure nitrogen sintering of the same material. Average room temperature bend strengths for hot isostatically pressed reaction bonded silicon nitride and high pressure nitrogen sintered reaction bonded silicon nitride were 767 and 670 MPa, respectively. Values of 472 and 495 MPa were observed at 1370 C. For specimens of similar but lower Y/sub 2/O/sub 3/ content produced from Si/sub 3/N/sub 4/ powder using the same high pressure nitrogen sintering conditions, the room temperature strength was 664 MPa and the 1370 C strength was 402 MPa. The greater strengths of the reaction bonded silicon nitride materials in comparison to the sintered silicon nitride powder material are attributed to the combined effect of processing method and higher Y/sub 2/O/sub 3/ content.

• Research Organization: National Aeronautics and Space Administration, Cleveland, OH (USA). Lewis Research Center
• OSTI ID: 6292296
• Report Number(s): N-89-15257; NASA-TM-101443; E-4429; NAS-1.15:101443
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360203* -- Ceramics
Cermets
& Refractories-- Mechanical Properties
ADDITIVES
CHALCOGENIDES
DATA
ELEMENTS
EXPERIMENTAL DATA
FABRICATION
HIGH PRESSURE
HOT PRESSING
INFORMATION
MATERIALS WORKING
MECHANICAL PROPERTIES
NITRIDES
NITROGEN
NITROGEN COMPOUNDS
NONMETALS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
PRESSING
SILICON COMPOUNDS
SILICON NITRIDES
SINTERING
TENSILE PROPERTIES
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES