Aqueous synthesis and sintering of zirconium titanate powders for microwave components

Zirconium titanate (ZT-ZrTiO4) is a well-known ferroelectric material commonly used as a dielectric in microwave devices due to its high permittivity at microwave frequencies. Reactive precursors of ZT in form of nanopowders have been prepared in a very simple way by hydrolysis of an aqueous solution of TiCl4 and ZrOCl2 using ammonia. ZT single-phase powder has been obtained by high temperature reaction during calcination at 1200 degreesC. alpha -PbO2-type structure was stabilised by air quenching to room temperature. Sinterability was investigated by constant heating-rate and isothermal sintering. High-density ceramics were obtained by firing performed at different temperatures and prototypes of substrates for microwave devices were prepared. (C) 2001 Elsevier Science Ltd. All rights reserved.