Electrophoretically Deposited Porous Ceramics and their Characterisation by X-Ray Computer Tomography

Abstract:

Planar zirconia green bodies with unidirectionally aligned pore channels were prepared by an electrophoretic deposition method using an effect which is usually disadvantageous for the EPD from aqueous suspensions: the formation of gas bubbles by electrolysis. Aqueous ZrO2 suspensions containing acetic acid to enable a sufficient gas generation were used for the EPD experiments. The influence of selected parameters – electrolyte content, applied voltage, and kind of deposition electrode – on the pore structure has been investigated. The green bodies were sintered at 1450 °C in air. Optical microscopy and X-ray computer tomography (CT) were used for characterising the porous structures. CT-investigations have the advantage of a three-dimensional characterisation of the samples by a non-destructive method. The resulting pore structure depended to a high degree on the experimental conditions of the EPD. The kind of the deposition electrode – platinum foil or platinum gauze on foil – had a strong influence on the arrangement of the pores. The EPD on Pt-foil led to randomly arranged pores, whereas very regular pore structures were obtained by the use of Pt-gauze.

• Periodical: Key Engineering Materials (Volume 412)
• Pages: 255-260
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.412.255
• Online since: June 2009
• Authors: Kirsten Moritz, Tassilo Moritz
• Keywords: Electrolysis, Electrophoretic Deposition (EPD), Porous Ceramics, X-Ray Computer Tomography

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