Enhanced electrical conductivity of ultrafine-grained 8Y(2)O(3) stabilized ZrO2 produced by two-step sintering technique

Mehdi Mazaheri
2010
Article

Résumé

Two-step sintering of nanocrystalline zirconia powder stabilized with 8 mol% yttria resulted in remarkable enhancement of the electrical conductivity and significant suppression of the accelerated grain growth. The electrical conductivity of the nearly full-dense structures obtained with an average grain size of 2.15 mu m at 900 degrees C was similar to 107 mS/cm. Two-step sintering resulted in reduction of the grain size to less than 300 nm and increase of the electrical conductivity to 209 mS/cm (i.e. >95% increase). These changes accompanied with a fracture toughness increase of more that 95% (from 1.61 to 3.16 MPa m(1/2)), too. (C) 2010 Elsevier B.V. All rights reserved.

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