Journal of the European Ceramic Society 18(1998) 1915-1921 Pinted in Great taesvier rignts reserved Printed in Great Britain. All rights reserved p:0955-2219(98)00130-7 0955-2219/98/5- see front matter Graceful Failure of Laminated Ceramic Tubes Produced by Electrophoretic Deposition Luc J. Vandeperre* and Omer O. Van Der Biest Departement Metaalkunde en Toegepaste Materiaalkunde Katholieke Universiteit te Leuven, De Croylaan 2, 3001 Heverlee,Belgium Abstract which makes it possible to obtain ceramic lami- nates of complex shape at low cost. Electrophoretic The production of silicon carbide laminated ceramic deposition is investigated, therefore, as a produc- tubes by electrophoretic deposition was investigated. tion process for complex shaped ceramic laminates Alternating deposition of SiC and graphite layers was since it has been shown that complex shapes can be obtained by depositing Sic from an acetone based obtained2and that this technique is very well suited suspension and by depositing the graphite interlayers to forming layered materials. Moreover, electro- oretic deposition has been used also to infiltrate nated tubes fibre preforms with a ceramic or glass-ceramic tubes were Electrophoretic deposition consists of applying graphite an electric field to a suspension of a charged cera- ponse to this electric field, the and supported lations powder particles move (electrophoresis)and for the expecte Heposit at the electrode of opposite charge. Shap- Elsevier Science Limited. ing is possible because the deposit takes the shape of the depositio Keywords: A. Shaping, B. Composites, C. Tough-E ent of a sus- ness, Toughening, D. SiC, electrophoretic depo-pension for electr of SiC, 6 the sition from which high epo 1.e graphit s and have a 1Introduction satistactory and electrophoretic deposit ed plates.?In Ceramic laminates have been introduced as a sim- this contribution deposition of ple way to obtain tough ceramic composites C/graphite lam d tubes is described, and Laminates consist of layers of ceramic material in the behaviour of rings cut from these tubes in between which weak interlayers are introduced. diametral compression is investigated. These materials show a tough behaviour because when a crack propagates through a strong layer, it flected into the Is dene nterlayer. As a result the 2 Experimental ther layers are ck and can continue to The electrode set-up consisted of a hollow graphite The processing techniques available today, how- cylinder as deposition electrode with a stainless ever, allow only relativel shapes to be steel rod situated in the centre as the counter elec- obtained. Taking into account possible applica-trode (Fig. 1). Poly-tetrafluorethylene(PTFE) tions for these. materials such as tubes for he exchangers and nozzles in chemical processing, it Further they provide support for the deposit dur- becomes apparent that there is a need for a process, ing drying he electrode set.up is attacthed an in-house developed automated deposition ce *To whom correspondence should be addressed. which controls the residence time in the different 1915