Rapid rate sintering of nanocrystalline ZrO{sub 2}-3 mol% Y{sub 2}O{sub 3}

Journal Article · Mon Apr 01 04:00:00 EST 1996 · Journal of the American Ceramic Society

DOI:https://doi.org/10.1111/j.1151-2916.1996.tb08524.x· OSTI ID:247909

Chen, D J; Mayo, M J ^[1]

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1. Pennsylvania State Univ., University Park, PA (United States). Dept. of Materials Science and Engineering

Conventional ramp-and-hold sintering with a wide range of heating rates was conducted on submicrometer and nanocrystalline ZrO{sub 2}-3 mol% Y{sub 2}O{sub 3} powder compacts. Although rapid heating rates have been reported to produce high density/fine grain size products for many submicrometer and smaller starting powders, the application of this technique to ZrO{sub 2}-3 mol% Y{sub 2}O{sub 3} produced mixed results. In the case of submicrometer ZrO{sub 2}-3 mol% Y{sub 2}O{sub 3}, neither densification nor grain growth was affected by the heating rate used. In the case of nanocrystalline ZrO{sub 2}-3 mol% Y{sub 2}O{sub 3}, fast heating rates severely retarded densification and had a minimal effect on grain growth. The large adverse effect of fast heating rates on the densification of the nanocrystalline powder was traced to a thermal gradient/differential densification effect. Microstructural evidence suggests that the rate of densification greatly exceeded the rate of heat transfer in this material; consequently, the sample interior was not able to densify before being geometrically constrained by a fully dense shell which formed at the sample exterior. This finding implies that rapid rate sintering will meet severe practical constraints in the manufacture of bulk nanocrystalline ZrO{sub 2}-3 mol% Y{sub 2}O{sub 3} specimens.

• Sponsoring Organization: USDOE
• OSTI ID: 247909
• Journal Information: Journal of the American Ceramic Society, Journal Name: Journal of the American Ceramic Society Journal Issue: 4 Vol. 79; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BULK DENSITY
COMPACTING
DIFFUSION
GRAIN BOUNDARIES
GRAIN GROWTH
HEAT TRANSFER
HEATING RATE
MICROSTRUCTURE
POWDERS
SINTERING
TEMPERATURE GRADIENTS
YTTRIUM OXIDES
ZIRCONIUM OXIDES