Microstructure and properties of single-crystal rare-earth oxide fibers

Single-crystal Ln 2 O 3 (Ln = Sm, Eu, Gd) fibers are grown by the laser-heated miniature pedestal technique. The relationship between the microstructure of fibers and their plasticity is analyzed using scanning electron microscopy, energy-dispersive microanalysis, electron backscatter diffraction, and X-ray methods. It is shown that the distinction between ductile and brittle fibers is determined basically by the difference in their microstructure. The fracture of samarium oxide fibers is associated with the formation of oxycarbonate phases on their surface. The most promising are the fibers of gadolinium oxide, having the most perfect microstructure, moisture and a carbon dioxide resistance, and a wide range of transparency.