Effect of Fe3+ and Y3+ Cations on the Crystallization of Tetragonal Zirconia under Mechanical Activation of Amorphous Zirconium Hydroxide
PETER N. KUZNETSOV1, LYUDMILA I. KUZNETSOVA1, ANATOLIY M. ZHYZHAEV1, GENNADIY L. PASHKOV1and VLADIMIR V. BOLDYREV2,3
1Institute of Chemistry and Chemical Technology, Siberian Branch of the Russian Academy of Sciences,
Ul. K. Marxa 42, Krasnoyarsk 660049 (Russia)
2Institute of Solid State Chemistry and Mechanochemistry,
Siberian Branch of the Russian Academy of Sciences,
Ul. Kutateladze 18, Novosibirsk 630128 (Russia)
3Novosibirsk State University, Ul. Pirogova 2, Novosibirsk 630090 (Russia) E-mail: kuzpn@krsk.info
Pages: 611-619
Abstract
The effect of mechanical activation of amorphous zirconium hydroxide in centrifugal planetary mill on the formation of crystalline zirconia in the presence of Fe3+ and Y3+ cation additives is investigated. It is established that the pulsed mechanical impact stimulates dehydration and crystallization of the nanosized metastable form of tetragonal zirconia in a mechanochemical apparatus at the room temperature. The solid-phase mechanochemical synthesis proceeds with a high rate through sequential and parallel routes with the intermediate formation of stable monoclinic modification of ZrO2. Introduction of additives favours the formation of the tetragonal form; in the presence of small amount of Y3+ cations, the process is completed within 2_5 min. The formation of metastable phase in the mechanochemical apparatus can occur due to the pulsed mode of powerful mechanical impact, resulting in the creation of thermodynamically and kinetically favourable conditions, and also due to small crystallite size (12_16 nm) as a result of efficient grinding.
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