Fabrication, properties and usage of single-crystalline YAG fibres

Single crystalline YAG fibres are now produced by an internal crystallization method. Essentially, the method is crystallization of the oxide melt infiltrated into continuous channels made in an auxiliary matrix, normally molybdenum, and then extracting the fibre from the auxiliary matrix by chemical dissolution of it. The method is relatively simple and requires sufficiently small energy input into a real process of the fibre production. Because crystallising a batch of the fibres by using ICM is actually similar to making bulk crystals an expected cost of ICM fibres is of the same order of magnitudes as that of bull crystals. It is shown that usage of ICM–YAG-fibres in a Ni-based matrix yields composites with high fibre/matrix interface strength and, hence, high creep resistance at very high temperatures for Ni-based materials.