Abstract
Measurements of marker spreading following 2.0 MeV Kr+ irradiation at 25 to 1300°C have been performed on MgO samples containing O18, Ca and Zn buried tracer atoms. Ion beam mixing at room temperature on both sublattices was approximately 2.0 to 3.0 angstrom5/eV. From 600 to 1000°C, the apparent activation enthalpy for diffusion on the anion sublattice (O18) was 0.35 eV and the diffusion coefficient was linear in the irradiation flux. From 1150 to 1300°C the measured activation enthalpy was 4.1 eV and the diffusion coefficient was proportional to the square root of flux. The measured activation enthalpy on the cation sublattice was roughly 0.30 eV up to 700°C for both Ca or Zn doped samples. Measurable extrinsic thermal diffusion from vacancies present for trivalent impurity charge compensation occurred above this temperature, complicating the analysis at higher temperatures. The observed kinetics in the lower temperature range are most likely controlled by interstitial loop formation. In the higher temperature range, vacancy traps with a binding energy of approximately 2 eV could account for the high activation enthalpy.
Original language | English (US) |
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Pages (from-to) | 293-298 |
Number of pages | 6 |
Journal | Materials Research Society Symposium - Proceedings |
Volume | 373 |
State | Published - 1995 |
Event | Proceedings of the 1994 MRS Fall Meeting - Boston, MA, USA Duration: Nov 28 1994 → Nov 30 1994 |
ASJC Scopus subject areas
- General Materials Science
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering