Oxide CMCs: interphase synthesis and novel fibre development

Strategies which have been used in the synthesis of high temperature interp hases with debond capability in oxide/oxide systems have been: (i) the form ation of layered oxides (beta-aluminas or magnetoplumbites) with preferred crystal orientation due to in-situ interface reactions between phases depos ited from vapour or liquid precursors and (ii) the deposition on fibre surf aces of complex oxides (vanadates and phosphates, principally of the rare e arths) from colloidal precursors or by magnetron sputtering. This paper is primarily concerned with the latter. The constitution and thermal stability of these interphases has been studied with reference to potential fibres a nd matrices (alumina, YAG and mullite). Included within the program are new ly developed single phase mullite fibres and examples of these are also pre sented. (C) 2000 Published by Elsevier Science Ltd. All rights reserved.