Swift heavy ion irradiation-induced microstructure modification of two delta-phase oxides: Sc_4Zr_3O_(12) and Lu_4Zr_3O_(12)

摘要

Swift gold ions (185 MeV) were used to systematically investigate the radiation damage response of delta phase compounds Sc_4Zr_3O_(12) and Lu_4Zr_3O_(12) in the electronic energy loss regime. Ion irradiation-induced microstructural modifications were examined using X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD investigations indicate a phase transformation from ordered rhombohedral to disordered fiuorite (O-D) in both compounds, with the Sc compound transforming at a higher ion fluence compared with the Lu compound. This result is consistent with our previous study on Sc_4Zr_3O_(12) and Lu_4Zr_3O_(12) under displacive radiation environment in which the nuclear energy loss is dominant. High resolution TEM revealed that individual ion tracks maintain crystalline structure, while the core region experiences an O-D phase transformation. TEM observations also suggest that for the doses in which the tracks overlap, the O-D phase transformation occurs across the entire ion range.