title: Fast crystallization of amorphous Gd2Zr2O7induced by thermally activated electron-beam irradiation.
abstract: We investigate the ionization and displacement effects of an electron-beam (e-beam) on amorphous Gd2Zr2O7synthesized 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 Gd2Zr2O7and is proposed to arise from the relatively lower surface and interface energy compared with the pyrochlore phase. Fast crystallization could be induced by 120 keV e-beam irradiation (beam current = 0.47 mA/cm2). The crystallization occurred on the nanoscale upon ionization irradiation at 400 °C after a dose of less than 1017electrons/cm2. 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.
authors.forename: Zhangyi
authors.initials: Z
authors.lastname: Huang
authors.forename: Jianqi
authors.initials: J
authors.lastname: Qi
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
authors.forename: Zhao
authors.initials: Z
authors.lastname: Feng
authors.forename: Xiaohe
authors.initials: X
authors.lastname: Yu
authors.affiliation: College of Materials Science and Engineering, Sichuan University , Chengdu 610064, China.
authors.forename: Yichao
authors.initials: Y
authors.lastname: Gong
authors.forename: Mao
authors.initials: M
authors.lastname: Yang
authors.forename: Qiwu
authors.initials: Q
authors.lastname: Shi
authors.forename: Nian
authors.initials: N
authors.lastname: Wei
authors.forename: Tiecheng
authors.initials: T
authors.lastname: Lu