Damage Accumulation and Amorphization in Samarium Titanate Pyrochlore

Journal Article · Tue Jun 01 04:00:00 EDT 2004 · Nuclear Instruments and Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms, 218(89-94

DOI:https://doi.org/10.1016/j.nimb.2003.12.003· OSTI ID:15007560

Zhang, Yanwen; Shutthanandan, V; Devanathan, Ram; Thevuthasan, Suntharampillai; McCready, David E; Young, James S; Balakrishnan, G; Paul, D M; Weber, William J

Damage accumulation in Sm2Ti₂O₇ single crystals irradiated with Au₂⁺ ions at 170, 300 and 700 K was studied by Rutherford backscattering spectrometry using a 2.0 MeV He⁺ beam along the <001> channeling direction. The relative disorder on the Sm sublattice follows a nonlinear dependence on ion fluence. The nonlinear behavior is described well by a disorder accumulation model that indicates a predominant role of a defect-stimulated amorphization process. The critical dose for amorphization at 300 K is ~0.14 dpa, which is in good agreement with in-situ transmission electron microscopy results for polycrystalline Sm₂Ti₂O₇ irradiated with 600 keV Bi⁺ ions and with Gd₂Ti₂O₇ doped with 244Cm. Despite the six orders of magnitude difference in damage rates, the good agreement between the amorphization doses in Sm2Ti₂O₇ at 300 K and 244Cm-doped Gd₂Ti₂O₇ at 340 K indicates that damage accumulation at these temperatures is relatively independent of dose rate.

• Research Organization: Pacific Northwest National Lab., Richland, WA (US), Environmental Molecular Sciences Laboratory (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 15007560
• Report Number(s): PNNL-SA-39437; 1237; 3448; KC0201020
• Journal Information: Nuclear Instruments and Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms, 218(89-94, Journal Name: Nuclear Instruments and Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms, 218(89-94
• Country of Publication: United States
• Language: English

Related Subjects

Amorphization
Irradiation damage
Pyrochlore
Rutherford backscattering spectroscopy
Samarium titanate
environmental molecular sciences laboratory