Improvement of creep resistance of sintered silicon nitride by hot isostatic exudation of intergranular glass

Journal Article · Mon Nov 01 04:00:00 EST 1993 · Journal of the American Ceramic Society; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1993.tb04017.x· OSTI ID:5722883

Rouxel, T; Besson, J ^[1]; Goursat, P ^[2]

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1. Lab. de Materiaux Ceramiques et Traitements de Surface, Limoges (France)
2. Univ. de Limoges (France)

Postsintering treatment of pressureless-sintered silicon nitride at 1,250 C (i.e., above the glass transition temperature of the amorphous phase) by hot isostatic pressing was performed to diminish the quantity of residual intergranular amorphous phase that results from densification aids. The samples were first embedded in a powder (SiC or Al[sub 2]O[sub 3]), which worked as a diffusion barrier and a pressure transmitter; then, both sample and surrounding powder were encapsulated in evacuated tubes of borosilicate glass or stainless steel. Energy dispersive X-ray spectrometry proved that, during the treatment, a noticeable amount of intergranular vitreous phase exuded out of the sample into powder pores. As a consequence, the creep resistance was enhanced by a factor of 3. When the HIP treatment was associated with a subsequent crystallization treatment, a further improvement in creep resistance was obtained.

• OSTI ID: 5722883
• Journal Information: Journal of the American Ceramic Society; (United States), Journal Name: Journal of the American Ceramic Society; (United States) Vol. 76:11; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601 -- Other Materials-- Preparation & Manufacture
360603* -- Materials-- Properties
CREEP
FABRICATION
GLASS
HOT PRESSING
MATERIALS WORKING
MECHANICAL PROPERTIES
NITRIDES
NITROGEN COMPOUNDS
PNICTIDES
POWDERS
PRESSING
SILICON COMPOUNDS
SILICON NITRIDES
SPECTRA
X-RAY SPECTRA