Lanthanum and neodymium zirconates and hafnates are promising materials for the production of thermal barrier coatings. In this work we synthesized and investigated fine-dispersed La₂Hf₂O₇, Nd₂Hf₂O₇, La₂Zr₂O₇ and Nd₂Zr₂O₇. Synthesis was carried out by means of hydrothermal and high-temperature self-propagating synthesis methods. The composition and purity of the synthesized compounds were investigated by laser mass-spectrometry method. Powders topography was investigated by means of high resolution optical microscopy; microstructure - by means of SEM, TEM. The thermal stability of the materials was investigated by isothermal annealing under 700°C for 1-30 hours and by TGA/DSC/DTA analysis up to 1500°C. The substances have been tested as components of thermal barrier coatings.

Keywords barrier coatings, ceramics, composites, electron microscopy, films, inorganic materials, nanostructures, pyrochlore, oxides, powder, pyrolysis, X-ray