Irradiation-induced amorphization of Ca{sub 2}La{sub 8}(SiO{sub 4}){sub 6}O{sub 2} single crystals

Conference · Sun Nov 01 04:00:00 EST 1992

OSTI ID:10114604

Weber, W J ^[1]; Wang, Lu-Min ^[2]

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1. Pacific Northwest Lab., Richland, WA (United States)
2. New Mexico Univ., Albuquerque, NM (United States). Dept. of Geology

Single crystals of Ca{sub 2}La{sub 8}(SiO{sub 4}){sub 6}O{sub 2} were irradiated with 1.5 MeV Xe{sup +}, 1.5 MeV Kr{sup +}, 1.0 MeV Ar{sup +}, and 0.8 MeV Ne{sup +} ions to investigate the effects of recoil-energy spectrum, temperature, and crystallographic orientation on irradiation-induced amorphization. The irradiations were carried out using the HVEM-Tandem Facility at Argonne National Laboratory. The structural changes and the ion fluence for complete amorphization in the electron transparent thickness of the specimens were determined by in situ transmission electron microscopy. The displacement dose determined for complete amorphization was approximately 0.6 dpa for the Xe{sup +}, Kr{sup +}, and Ar{sup +} ion irradiations, but increased to 1.5 dpa for the Ne{sup +} ion irradiations, which may reflect an effect of lower recoil energies. The ion fluence for complete amorphization increased exponentially with temperature over the range from 25 to 400{degree}C. Amorphization was not observed at 500{degree}C. The activation energy associated with this simultaneous recrystallization process was estimated to be 0.13 eV, and the critical amorphization temperature was estimated to be 438{degree}C.

• Research Organization: Pacific Northwest Lab., Richland, WA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 10114604
• Report Number(s): PNL-SA--21128; CONF-921101--20; ON: DE93004835
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360605
AMORPHOUS STATE
ARGON IONS
CALCIUM OXIDES
CALCIUM SILICATES
DISPLACEMENT RATES
ION BEAMS
KEV RANGE 100-1000
KRYPTON IONS
LANTHANUM OXIDES
LANTHANUM SILICATES
MEV RANGE 01-10
MONOCRYSTALS
NEON IONS
PHYSICAL RADIATION EFFECTS
RADIATION DOSES
RADIATION EFFECTS
TEMPERATURE DEPENDENCE
VITRIFICATION
XENON IONS