Microstructural features of the ZrO2 interfacial coatings on SiC fibers before and after exposition to air at high temperatures

Sols of rare earth stabilized zirconia were used as simple, readily processable and accurate controllable precursors for the tetragonal zirconia interfacial coatings on commercially available SiC-based fibers. The tetragonal zirconia interfacial coatings can be applied to different types of SiC fibers without degrading fiber strength. The morphology, composition, structure, nanorelief and oxidation resistance of coated SiC fibers were evaluated by various analytical techniques, including scanning electron microscopy/energy dispersive analysis, transmission electron microscopy, atomic force microscopy in various modes, and micro-Raman spectroscopy. It was shown that the microstructural peculiarities of the ReZrO2 interfacial coatings on SiC-based fibers may explain some of the differences in the behavior of different types of fibers.