Development of secondary phases on Synroc leached at 150 C
- Australian Nuclear Science and Technology Organisation, Menai, New South Wales (Australia). Advanced Materials Program
Electron microscopy techniques were used to identify secondary phases on the surface of Synroc after exposure to doubly deionized water (DDW) at 150 C for time periods up to 532 days. After one day, TiO{sub 2} develops on perovskite in the form of polycrystalline crusts of anatase or epitaxial crystals of brookite ({+-} anatase), and as scattered single crystals on hollandite and rutile-Magneli phases. With increasing exposure time the anatase crusts exhibit slow grain growth and development of preferred orientation; whereas, the epitaxial brookite crystals appear to grow more rapidly. Dissolution of perovskite and P-bearing intermetallic particles results indirectly in the precipitation of monazite after 84 days. Additional alteration products observed over a range of time include crystalline Al-O-H phases and amorphous to poorly crystalline Fe-O-H phases which form as a result of the dissolution of Al-rich oxides and Fe-bearing intermetallic grains, respectively. A poorly crystalline Ru-O-H phase was found as an alteration product of Ru-bearing intermetallic particles after exposure to DDW for 336 days.
- OSTI ID:
- 382860
- Report Number(s):
- CONF-941075-; ISBN 1-55899-253-7; TRN: 96:025752
- Resource Relation:
- Conference: 18. international symposium on the scientific basis for nuclear waste management, Kyoto (Japan), 23-27 Oct 1994; Other Information: PBD: 1995; Related Information: Is Part Of Scientific basis for nuclear waste management 18. Part 2; Murakami, Takashi [ed.] [Ehime Univ., Matsuyama, Ehime (Japan). Dept. of Earth Sciences]; Ewing, R.C. [ed.] [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Earth and Planetary Sciences]; PB: 690 p.; Materials Research Society symposium proceedings, Volume 353
- Country of Publication:
- United States
- Language:
- English
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