Ion-irradiation-induced phase transformation in rare earth sesquioxides (Dy{sub 2}O{sub 3},Er{sub 2}O{sub 3},Lu{sub 2}O{sub 3})

Journal Article · Wed Mar 15 00:00:00 EST 2006 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.2184433· OSTI ID:20787973

Tang, M; Lu, P; Valdez, J A; Sickafus, K E ^[1]

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1. Department of Materials and Metallurgical Engineering, New Mexico Institute of Mining and Technology, Socorro, New Mexico 87801 (United States) and Material Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

Polycrystalline pellets of cubic C-type rare earth structure (Ia3) Dy{sub 2}O{sub 3}, Er{sub 2}O{sub 3}, and Lu{sub 2}O{sub 3} were irradiated at cryogenic temperature (120 K) with 300 keV Kr{sup ++} ions to a maximum fluence of 1x10{sup 20} Kr/m{sup 2}. Irradiated specimens were examined using grazing incidence x-ray diffraction and transmission electron microscopy. Ion irradiation leads to different radiation effects in these three materials. First, Dy{sub 2}O{sub 3} begins to transform to a monoclinic B-type rare earth structure (C2/m) at a peak dose of {approx}5 displacements per atom (dpa) (corresponding to a fluence of 2x10{sup 19} Kr/m{sup 2}). This transformation is nearly complete at a peak dose of 25 dpa (a fluence of 1x10{sup 20} Kr/m{sup 2}). Er{sub 2}O{sub 3} also transforms to the B-type structure, but the transformation starts at a higher irradiation dose of about 15-20 dpa [a fluence of about (6-8)x10{sup 19} Kr/m{sup 2}]. Lu{sub 2}O{sub 3} was found to maintain the C-type structure even at the highest irradiation dose of 25 dpa (a fluence of 1x10{sup 20} Kr/m{sup 2}). No C-to-B transformation was observed in Lu{sub 2}O{sub 3}. The irradiation dose dependence of the C-to-B phase transformation observed in Dy{sub 2}O{sub 3}, Er{sub 2}O{sub 3}, and Lu{sub 2}O{sub 3} is closely related to the temperature dependence of the C-to-B phase transformation found in phase diagrams for these three materials.

• OSTI ID: 20787973
• Journal Information: Journal of Applied Physics, Vol. 99, Issue 6; Other Information: DOI: 10.1063/1.2184433; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ATOMIC DISPLACEMENTS
DYSPROSIUM OXIDES
ERBIUM OXIDES
ION BEAMS
IRRADIATION
KEV RANGE 100-1000
KRYPTON IONS
LUTETIUM OXIDES
MONOCLINIC LATTICES
PELLETS
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
POLYCRYSTALS
RADIATION DOSES
TEMPERATURE DEPENDENCE
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION