Chakravarty, Dibyendu and Chokshi, Atul H (2015) Influence of yttria and zirconia additions on spark plasma sintering of alumina composites. In: JOURNAL OF MATERIALS RESEARCH, 30 (8). pp. 1148-1156.
Full text not available from this repository. (Request a copy)Abstract
The mechanisms of densification and creep were examined during spark plasma sintering (SPS) of alumina doped with a low and high level of zirconia or yttria, over a temperature range of 1173-1573 K and stresses between 25 and 100 MPa. Large additions of yttria led clearly to in situ reactions during SPS and the formation of a yttrium-aluminum garnet phase. Dopants generally lead to a reduction in the densification rate, with substantial reductions noted in samples with similar to 5.5 vol% second phase. In contrast to a stress exponent of n similar to 1 for pure alumina, the doped aluminas displayed n similar to 2 corresponding to an interface-controlled diffusion process. The higher activation energies in the composites are consistent with previous data on creep and changes in the interfacial energies. The results reveal a compensation effect, such that an increase in the activation energy is accompanied by a corresponding increase in the pre-exponential term for diffusion.
Item Type: | Journal Article |
---|---|
Publication: | JOURNAL OF MATERIALS RESEARCH |
Publisher: | CAMBRIDGE UNIV PRESS |
Additional Information: | Copy right for this article belongs to the CAMBRIDGE UNIV PRESS, 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA |
Department/Centre: | Division of Mechanical Sciences > Materials Engineering (formerly Metallurgy) |
Date Deposited: | 26 Jun 2015 07:32 |
Last Modified: | 26 Jun 2015 07:32 |
URI: | http://eprints.iisc.ac.in/id/eprint/51782 |
Actions (login required)
View Item |