Fast crystallization of amorphous Gd2Zr2O7 induced by thermally activated electron-beam irradiation

Abstract

We investigate the ionization and displacement effects of an electron-beam (e-beam) on amorphous Gd 2 Zr 2 O 7 synthesized by the co-precipitation and calcination methods. The as-received amorphous specimens were irradiated under electron beams at different energies (80 keV, 120 keV, and 2 MeV) and then characterized by X-ray diffraction and transmission electron microscopy. A metastable fluorite phase was observed in nanocrystalline Gd 2 Zr 2 O 7 and is proposed to arise from the relatively lower surface and interface energy compared with the pyrochlore phase. . Under e-beam irradiation, the activation energy for the grain growth process was approximately 10 kJ/mol, but the activation energy was 135 kJ/mol by calcination in a furnace. The thermally activated ionization process was considered the fast crystallization mechanism. V C 2015 AIP Publishing LLC. [http://dx

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