ISSN:
1551-2916
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
In order to understand the reactions of yttria-containing zirconia powder in aqueous solution, the dissolution behavior of yttrium and the formation of the monoclinic (m) phase of the Y-TZP powder were investigated. The tests were conducted in aqueous solution at temperatures up to 95°C. The results showed that the reaction order of yttrium dissolution from the surface of TZP powder is 5-9, and the activation energy is about 8.4 kJ/mol. However, the value of the reaction order is different from that (0.96-1.20) of the formation of m-phase. However, the yttrium dissolution of the slurries with the addition of 2 mol% dispersant (D-134) was reduced greatly to an extremely low (〈2 ppm) level up to 24 h at the testing temperatures. The results also showed that the amounts of m-phase formation were nearly the same for the powders in the slurries with or without D-134 addition. The decrease of yttrium content in the presence of D-134 and the formation of the m-phase of the TZP powder were not closely related. The degradation mechanism, or the formation of m-phase, should not be directly related to the dissolution of yttrium ions from a zirconia surface.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1151-2916.1999.tb01971.x
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