Dopant Distributions in Rare‐Earth‐Doped Alumina
Authors:
- 1 February 1997
- journal article
- Published by Wiley in Journal of the American Ceramic Society
- Vol. 80 (2) , 373-376
Abstract
The distribution of yttrium and lanthanum dopants has been mapped in yttrium‐ and lanthanum‐doped polycrystalline aluminas using imaging secondary‐ion mass spectrometry (imaging‐SIMS). Both dopants segregate to grain boundaries and pore surfaces. On average, yttrium occupies 7.1%–9.0% of the available grain‐boundary cation sites, whereas lanthanum occupies only 2.0%–5.2%. In 1000‐ppm‐yttrium‐doped alumina, an abundance of yttrium aluminum garnet precipitates also is observed. Implications of these observations to the creep behavior of alumina are discussed. The similarity in the segregation behavior of yttrium and lanthanum highlights the potential of lanthanum‐doped alumina for improved creep properties.Keywords
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