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Compositional effects on Si3N4 fracture surfacesSurface analysis techniques (X-ray, infrared reflection spectroscopy, Auger electron spectroscopy) applied to the same samples reveal that fracture surfaces of Si3N4 with Y2O3 densification aids possess a higher concentration of oxygen than the bulk. The oxide densification aids thus concentrate in the grain boundaries, and even low-temperature fracture is seen as occurring preferentially within the oxygen-enriched grain boundaries. It is found that increasing the concentrations of Y2O3 and Al2O3 increases the oxygen content of the fracture surface. A range of 13-15 percent Y2O3 + 6 percent Al2O3 gives an amorphous grain-boundary phase that is resistant to devitrification. Fracture occurs through the amorphous phase, and heat treatment at 1000 C has little effect on the amorphous phase.
Document ID
19840037007
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Hench, L. L.
(Florida, University Gainesville, FL, United States)
Ohuchi, F.
(Du Pont de Nemours and Co. Wilmington, DE, United States)
Vaidyanathan, P. N.
(Warner and Swasey Co., Manchester Div., Akron OH, United States)
Dutta, S.
(NASA Lewis Research Center Cleveland, OH, United States)
Date Acquired
August 12, 2013
Publication Date
October 1, 1983
Publication Information
Publication: Ceramic Engineering and Science Proceedings
Volume: 4
ISSN: 0196-6219
Subject Category
Nonmetallic Materials
Accession Number
84A19794
Funding Number(s)
CONTRACT_GRANT: NSG-3254
Distribution Limits
Public
Copyright
Other

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